tty: move hvc drivers to drivers/tty/hvc/
authorGreg Kroah-Hartman <gregkh@suse.de>
Thu, 13 Jan 2011 20:03:00 +0000 (12:03 -0800)
committerGreg Kroah-Hartman <gregkh@suse.de>
Thu, 13 Jan 2011 20:03:00 +0000 (12:03 -0800)
As requested by Arnd Bergmann, the hvc drivers are now
moved to the drivers/tty/hvc/ directory.  The virtio_console.c driver
was also moved, as it required the hvc_console.h file to be able to be
built, and it really is a hvc driver.

Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

33 files changed:
drivers/char/Makefile
drivers/char/hvc_beat.c [deleted file]
drivers/char/hvc_console.c [deleted file]
drivers/char/hvc_console.h [deleted file]
drivers/char/hvc_dcc.c [deleted file]
drivers/char/hvc_irq.c [deleted file]
drivers/char/hvc_iseries.c [deleted file]
drivers/char/hvc_iucv.c [deleted file]
drivers/char/hvc_rtas.c [deleted file]
drivers/char/hvc_tile.c [deleted file]
drivers/char/hvc_udbg.c [deleted file]
drivers/char/hvc_vio.c [deleted file]
drivers/char/hvc_xen.c [deleted file]
drivers/char/hvcs.c [deleted file]
drivers/char/hvsi.c [deleted file]
drivers/char/virtio_console.c [deleted file]
drivers/tty/Makefile
drivers/tty/hvc/Makefile [new file with mode: 0644]
drivers/tty/hvc/hvc_beat.c [new file with mode: 0644]
drivers/tty/hvc/hvc_console.c [new file with mode: 0644]
drivers/tty/hvc/hvc_console.h [new file with mode: 0644]
drivers/tty/hvc/hvc_dcc.c [new file with mode: 0644]
drivers/tty/hvc/hvc_irq.c [new file with mode: 0644]
drivers/tty/hvc/hvc_iseries.c [new file with mode: 0644]
drivers/tty/hvc/hvc_iucv.c [new file with mode: 0644]
drivers/tty/hvc/hvc_rtas.c [new file with mode: 0644]
drivers/tty/hvc/hvc_tile.c [new file with mode: 0644]
drivers/tty/hvc/hvc_udbg.c [new file with mode: 0644]
drivers/tty/hvc/hvc_vio.c [new file with mode: 0644]
drivers/tty/hvc/hvc_xen.c [new file with mode: 0644]
drivers/tty/hvc/hvcs.c [new file with mode: 0644]
drivers/tty/hvc/hvsi.c [new file with mode: 0644]
drivers/tty/hvc/virtio_console.c [new file with mode: 0644]

index 1e9dffb..5bc765d 100644 (file)
@@ -30,25 +30,12 @@ obj-$(CONFIG_SYNCLINK_GT)   += synclink_gt.o
 obj-$(CONFIG_AMIGA_BUILTIN_SERIAL) += amiserial.o
 obj-$(CONFIG_SX)               += sx.o generic_serial.o
 obj-$(CONFIG_RIO)              += rio/ generic_serial.o
-obj-$(CONFIG_HVC_CONSOLE)      += hvc_vio.o hvsi.o
-obj-$(CONFIG_HVC_ISERIES)      += hvc_iseries.o
-obj-$(CONFIG_HVC_RTAS)         += hvc_rtas.o
-obj-$(CONFIG_HVC_TILE)         += hvc_tile.o
-obj-$(CONFIG_HVC_DCC)          += hvc_dcc.o
-obj-$(CONFIG_HVC_BEAT)         += hvc_beat.o
-obj-$(CONFIG_HVC_DRIVER)       += hvc_console.o
-obj-$(CONFIG_HVC_IRQ)          += hvc_irq.o
-obj-$(CONFIG_HVC_XEN)          += hvc_xen.o
-obj-$(CONFIG_HVC_IUCV)         += hvc_iucv.o
-obj-$(CONFIG_HVC_UDBG)         += hvc_udbg.o
-obj-$(CONFIG_VIRTIO_CONSOLE)   += virtio_console.o
 obj-$(CONFIG_RAW_DRIVER)       += raw.o
 obj-$(CONFIG_SGI_SNSC)         += snsc.o snsc_event.o
 obj-$(CONFIG_MSPEC)            += mspec.o
 obj-$(CONFIG_MMTIMER)          += mmtimer.o
 obj-$(CONFIG_UV_MMTIMER)       += uv_mmtimer.o
 obj-$(CONFIG_VIOTAPE)          += viotape.o
-obj-$(CONFIG_HVCS)             += hvcs.o
 obj-$(CONFIG_IBM_BSR)          += bsr.o
 obj-$(CONFIG_SGI_MBCS)         += mbcs.o
 obj-$(CONFIG_BRIQ_PANEL)       += briq_panel.o
diff --git a/drivers/char/hvc_beat.c b/drivers/char/hvc_beat.c
deleted file mode 100644 (file)
index 5fe4631..0000000
+++ /dev/null
@@ -1,134 +0,0 @@
-/*
- * Beat hypervisor console driver
- *
- * (C) Copyright 2006 TOSHIBA CORPORATION
- *
- * This code is based on drivers/char/hvc_rtas.c:
- * (C) Copyright IBM Corporation 2001-2005
- * (C) Copyright Red Hat, Inc. 2005
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
- */
-
-#include <linux/module.h>
-#include <linux/init.h>
-#include <linux/err.h>
-#include <linux/string.h>
-#include <linux/console.h>
-#include <asm/prom.h>
-#include <asm/hvconsole.h>
-#include <asm/firmware.h>
-
-#include "hvc_console.h"
-
-extern int64_t beat_get_term_char(uint64_t, uint64_t *, uint64_t *, uint64_t *);
-extern int64_t beat_put_term_char(uint64_t, uint64_t, uint64_t, uint64_t);
-
-struct hvc_struct *hvc_beat_dev = NULL;
-
-/* bug: only one queue is available regardless of vtermno */
-static int hvc_beat_get_chars(uint32_t vtermno, char *buf, int cnt)
-{
-       static unsigned char q[sizeof(unsigned long) * 2]
-               __attribute__((aligned(sizeof(unsigned long))));
-       static int qlen = 0;
-       u64 got;
-
-again:
-       if (qlen) {
-               if (qlen > cnt) {
-                       memcpy(buf, q, cnt);
-                       qlen -= cnt;
-                       memmove(q + cnt, q, qlen);
-                       return cnt;
-               } else {        /* qlen <= cnt */
-                       int     r;
-
-                       memcpy(buf, q, qlen);
-                       r = qlen;
-                       qlen = 0;
-                       return r;
-               }
-       }
-       if (beat_get_term_char(vtermno, &got,
-               ((u64 *)q), ((u64 *)q) + 1) == 0) {
-               qlen = got;
-               goto again;
-       }
-       return 0;
-}
-
-static int hvc_beat_put_chars(uint32_t vtermno, const char *buf, int cnt)
-{
-       unsigned long kb[2];
-       int rest, nlen;
-
-       for (rest = cnt; rest > 0; rest -= nlen) {
-               nlen = (rest > 16) ? 16 : rest;
-               memcpy(kb, buf, nlen);
-               beat_put_term_char(vtermno, nlen, kb[0], kb[1]);
-               buf += nlen;
-       }
-       return cnt;
-}
-
-static const struct hv_ops hvc_beat_get_put_ops = {
-       .get_chars = hvc_beat_get_chars,
-       .put_chars = hvc_beat_put_chars,
-};
-
-static int hvc_beat_useit = 1;
-
-static int hvc_beat_config(char *p)
-{
-       hvc_beat_useit = simple_strtoul(p, NULL, 0);
-       return 0;
-}
-
-static int __init hvc_beat_console_init(void)
-{
-       if (hvc_beat_useit && of_machine_is_compatible("Beat")) {
-               hvc_instantiate(0, 0, &hvc_beat_get_put_ops);
-       }
-       return 0;
-}
-
-/* temp */
-static int __init hvc_beat_init(void)
-{
-       struct hvc_struct *hp;
-
-       if (!firmware_has_feature(FW_FEATURE_BEAT))
-               return -ENODEV;
-
-       hp = hvc_alloc(0, NO_IRQ, &hvc_beat_get_put_ops, 16);
-       if (IS_ERR(hp))
-               return PTR_ERR(hp);
-       hvc_beat_dev = hp;
-       return 0;
-}
-
-static void __exit hvc_beat_exit(void)
-{
-       if (hvc_beat_dev)
-               hvc_remove(hvc_beat_dev);
-}
-
-module_init(hvc_beat_init);
-module_exit(hvc_beat_exit);
-
-__setup("hvc_beat=", hvc_beat_config);
-
-console_initcall(hvc_beat_console_init);
diff --git a/drivers/char/hvc_console.c b/drivers/char/hvc_console.c
deleted file mode 100644 (file)
index e9cba13..0000000
+++ /dev/null
@@ -1,914 +0,0 @@
-/*
- * Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM
- * Copyright (C) 2001 Paul Mackerras <paulus@au.ibm.com>, IBM
- * Copyright (C) 2004 Benjamin Herrenschmidt <benh@kernel.crashing.org>, IBM Corp.
- * Copyright (C) 2004 IBM Corporation
- *
- * Additional Author(s):
- *  Ryan S. Arnold <rsa@us.ibm.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- * 
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- * 
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
- */
-
-#include <linux/console.h>
-#include <linux/cpumask.h>
-#include <linux/init.h>
-#include <linux/kbd_kern.h>
-#include <linux/kernel.h>
-#include <linux/kthread.h>
-#include <linux/list.h>
-#include <linux/module.h>
-#include <linux/major.h>
-#include <linux/sysrq.h>
-#include <linux/tty.h>
-#include <linux/tty_flip.h>
-#include <linux/sched.h>
-#include <linux/spinlock.h>
-#include <linux/delay.h>
-#include <linux/freezer.h>
-#include <linux/slab.h>
-
-#include <asm/uaccess.h>
-
-#include "hvc_console.h"
-
-#define HVC_MAJOR      229
-#define HVC_MINOR      0
-
-/*
- * Wait this long per iteration while trying to push buffered data to the
- * hypervisor before allowing the tty to complete a close operation.
- */
-#define HVC_CLOSE_WAIT (HZ/100) /* 1/10 of a second */
-
-/*
- * These sizes are most efficient for vio, because they are the
- * native transfer size. We could make them selectable in the
- * future to better deal with backends that want other buffer sizes.
- */
-#define N_OUTBUF       16
-#define N_INBUF                16
-
-#define __ALIGNED__ __attribute__((__aligned__(sizeof(long))))
-
-static struct tty_driver *hvc_driver;
-static struct task_struct *hvc_task;
-
-/* Picks up late kicks after list walk but before schedule() */
-static int hvc_kicked;
-
-static int hvc_init(void);
-
-#ifdef CONFIG_MAGIC_SYSRQ
-static int sysrq_pressed;
-#endif
-
-/* dynamic list of hvc_struct instances */
-static LIST_HEAD(hvc_structs);
-
-/*
- * Protect the list of hvc_struct instances from inserts and removals during
- * list traversal.
- */
-static DEFINE_SPINLOCK(hvc_structs_lock);
-
-/*
- * This value is used to assign a tty->index value to a hvc_struct based
- * upon order of exposure via hvc_probe(), when we can not match it to
- * a console candidate registered with hvc_instantiate().
- */
-static int last_hvc = -1;
-
-/*
- * Do not call this function with either the hvc_structs_lock or the hvc_struct
- * lock held.  If successful, this function increments the kref reference
- * count against the target hvc_struct so it should be released when finished.
- */
-static struct hvc_struct *hvc_get_by_index(int index)
-{
-       struct hvc_struct *hp;
-       unsigned long flags;
-
-       spin_lock(&hvc_structs_lock);
-
-       list_for_each_entry(hp, &hvc_structs, next) {
-               spin_lock_irqsave(&hp->lock, flags);
-               if (hp->index == index) {
-                       kref_get(&hp->kref);
-                       spin_unlock_irqrestore(&hp->lock, flags);
-                       spin_unlock(&hvc_structs_lock);
-                       return hp;
-               }
-               spin_unlock_irqrestore(&hp->lock, flags);
-       }
-       hp = NULL;
-
-       spin_unlock(&hvc_structs_lock);
-       return hp;
-}
-
-
-/*
- * Initial console vtermnos for console API usage prior to full console
- * initialization.  Any vty adapter outside this range will not have usable
- * console interfaces but can still be used as a tty device.  This has to be
- * static because kmalloc will not work during early console init.
- */
-static const struct hv_ops *cons_ops[MAX_NR_HVC_CONSOLES];
-static uint32_t vtermnos[MAX_NR_HVC_CONSOLES] =
-       {[0 ... MAX_NR_HVC_CONSOLES - 1] = -1};
-
-/*
- * Console APIs, NOT TTY.  These APIs are available immediately when
- * hvc_console_setup() finds adapters.
- */
-
-static void hvc_console_print(struct console *co, const char *b,
-                             unsigned count)
-{
-       char c[N_OUTBUF] __ALIGNED__;
-       unsigned i = 0, n = 0;
-       int r, donecr = 0, index = co->index;
-
-       /* Console access attempt outside of acceptable console range. */
-       if (index >= MAX_NR_HVC_CONSOLES)
-               return;
-
-       /* This console adapter was removed so it is not usable. */
-       if (vtermnos[index] == -1)
-               return;
-
-       while (count > 0 || i > 0) {
-               if (count > 0 && i < sizeof(c)) {
-                       if (b[n] == '\n' && !donecr) {
-                               c[i++] = '\r';
-                               donecr = 1;
-                       } else {
-                               c[i++] = b[n++];
-                               donecr = 0;
-                               --count;
-                       }
-               } else {
-                       r = cons_ops[index]->put_chars(vtermnos[index], c, i);
-                       if (r <= 0) {
-                               /* throw away chars on error */
-                               i = 0;
-                       } else if (r > 0) {
-                               i -= r;
-                               if (i > 0)
-                                       memmove(c, c+r, i);
-                       }
-               }
-       }
-}
-
-static struct tty_driver *hvc_console_device(struct console *c, int *index)
-{
-       if (vtermnos[c->index] == -1)
-               return NULL;
-
-       *index = c->index;
-       return hvc_driver;
-}
-
-static int __init hvc_console_setup(struct console *co, char *options)
-{
-       if (co->index < 0 || co->index >= MAX_NR_HVC_CONSOLES)
-               return -ENODEV;
-
-       if (vtermnos[co->index] == -1)
-               return -ENODEV;
-
-       return 0;
-}
-
-static struct console hvc_console = {
-       .name           = "hvc",
-       .write          = hvc_console_print,
-       .device         = hvc_console_device,
-       .setup          = hvc_console_setup,
-       .flags          = CON_PRINTBUFFER,
-       .index          = -1,
-};
-
-/*
- * Early console initialization.  Precedes driver initialization.
- *
- * (1) we are first, and the user specified another driver
- * -- index will remain -1
- * (2) we are first and the user specified no driver
- * -- index will be set to 0, then we will fail setup.
- * (3)  we are first and the user specified our driver
- * -- index will be set to user specified driver, and we will fail
- * (4) we are after driver, and this initcall will register us
- * -- if the user didn't specify a driver then the console will match
- *
- * Note that for cases 2 and 3, we will match later when the io driver
- * calls hvc_instantiate() and call register again.
- */
-static int __init hvc_console_init(void)
-{
-       register_console(&hvc_console);
-       return 0;
-}
-console_initcall(hvc_console_init);
-
-/* callback when the kboject ref count reaches zero. */
-static void destroy_hvc_struct(struct kref *kref)
-{
-       struct hvc_struct *hp = container_of(kref, struct hvc_struct, kref);
-       unsigned long flags;
-
-       spin_lock(&hvc_structs_lock);
-
-       spin_lock_irqsave(&hp->lock, flags);
-       list_del(&(hp->next));
-       spin_unlock_irqrestore(&hp->lock, flags);
-
-       spin_unlock(&hvc_structs_lock);
-
-       kfree(hp);
-}
-
-/*
- * hvc_instantiate() is an early console discovery method which locates
- * consoles * prior to the vio subsystem discovering them.  Hotplugged
- * vty adapters do NOT get an hvc_instantiate() callback since they
- * appear after early console init.
- */
-int hvc_instantiate(uint32_t vtermno, int index, const struct hv_ops *ops)
-{
-       struct hvc_struct *hp;
-
-       if (index < 0 || index >= MAX_NR_HVC_CONSOLES)
-               return -1;
-
-       if (vtermnos[index] != -1)
-               return -1;
-
-       /* make sure no no tty has been registered in this index */
-       hp = hvc_get_by_index(index);
-       if (hp) {
-               kref_put(&hp->kref, destroy_hvc_struct);
-               return -1;
-       }
-
-       vtermnos[index] = vtermno;
-       cons_ops[index] = ops;
-
-       /* reserve all indices up to and including this index */
-       if (last_hvc < index)
-               last_hvc = index;
-
-       /* if this index is what the user requested, then register
-        * now (setup won't fail at this point).  It's ok to just
-        * call register again if previously .setup failed.
-        */
-       if (index == hvc_console.index)
-               register_console(&hvc_console);
-
-       return 0;
-}
-EXPORT_SYMBOL_GPL(hvc_instantiate);
-
-/* Wake the sleeping khvcd */
-void hvc_kick(void)
-{
-       hvc_kicked = 1;
-       wake_up_process(hvc_task);
-}
-EXPORT_SYMBOL_GPL(hvc_kick);
-
-static void hvc_unthrottle(struct tty_struct *tty)
-{
-       hvc_kick();
-}
-
-/*
- * The TTY interface won't be used until after the vio layer has exposed the vty
- * adapter to the kernel.
- */
-static int hvc_open(struct tty_struct *tty, struct file * filp)
-{
-       struct hvc_struct *hp;
-       unsigned long flags;
-       int rc = 0;
-
-       /* Auto increments kref reference if found. */
-       if (!(hp = hvc_get_by_index(tty->index)))
-               return -ENODEV;
-
-       spin_lock_irqsave(&hp->lock, flags);
-       /* Check and then increment for fast path open. */
-       if (hp->count++ > 0) {
-               tty_kref_get(tty);
-               spin_unlock_irqrestore(&hp->lock, flags);
-               hvc_kick();
-               return 0;
-       } /* else count == 0 */
-
-       tty->driver_data = hp;
-
-       hp->tty = tty_kref_get(tty);
-
-       spin_unlock_irqrestore(&hp->lock, flags);
-
-       if (hp->ops->notifier_add)
-               rc = hp->ops->notifier_add(hp, hp->data);
-
-       /*
-        * If the notifier fails we return an error.  The tty layer
-        * will call hvc_close() after a failed open but we don't want to clean
-        * up there so we'll clean up here and clear out the previously set
-        * tty fields and return the kref reference.
-        */
-       if (rc) {
-               spin_lock_irqsave(&hp->lock, flags);
-               hp->tty = NULL;
-               spin_unlock_irqrestore(&hp->lock, flags);
-               tty_kref_put(tty);
-               tty->driver_data = NULL;
-               kref_put(&hp->kref, destroy_hvc_struct);
-               printk(KERN_ERR "hvc_open: request_irq failed with rc %d.\n", rc);
-       }
-       /* Force wakeup of the polling thread */
-       hvc_kick();
-
-       return rc;
-}
-
-static void hvc_close(struct tty_struct *tty, struct file * filp)
-{
-       struct hvc_struct *hp;
-       unsigned long flags;
-
-       if (tty_hung_up_p(filp))
-               return;
-
-       /*
-        * No driver_data means that this close was issued after a failed
-        * hvc_open by the tty layer's release_dev() function and we can just
-        * exit cleanly because the kref reference wasn't made.
-        */
-       if (!tty->driver_data)
-               return;
-
-       hp = tty->driver_data;
-
-       spin_lock_irqsave(&hp->lock, flags);
-
-       if (--hp->count == 0) {
-               /* We are done with the tty pointer now. */
-               hp->tty = NULL;
-               spin_unlock_irqrestore(&hp->lock, flags);
-
-               if (hp->ops->notifier_del)
-                       hp->ops->notifier_del(hp, hp->data);
-
-               /* cancel pending tty resize work */
-               cancel_work_sync(&hp->tty_resize);
-
-               /*
-                * Chain calls chars_in_buffer() and returns immediately if
-                * there is no buffered data otherwise sleeps on a wait queue
-                * waking periodically to check chars_in_buffer().
-                */
-               tty_wait_until_sent(tty, HVC_CLOSE_WAIT);
-       } else {
-               if (hp->count < 0)
-                       printk(KERN_ERR "hvc_close %X: oops, count is %d\n",
-                               hp->vtermno, hp->count);
-               spin_unlock_irqrestore(&hp->lock, flags);
-       }
-
-       tty_kref_put(tty);
-       kref_put(&hp->kref, destroy_hvc_struct);
-}
-
-static void hvc_hangup(struct tty_struct *tty)
-{
-       struct hvc_struct *hp = tty->driver_data;
-       unsigned long flags;
-       int temp_open_count;
-
-       if (!hp)
-               return;
-
-       /* cancel pending tty resize work */
-       cancel_work_sync(&hp->tty_resize);
-
-       spin_lock_irqsave(&hp->lock, flags);
-
-       /*
-        * The N_TTY line discipline has problems such that in a close vs
-        * open->hangup case this can be called after the final close so prevent
-        * that from happening for now.
-        */
-       if (hp->count <= 0) {
-               spin_unlock_irqrestore(&hp->lock, flags);
-               return;
-       }
-
-       temp_open_count = hp->count;
-       hp->count = 0;
-       hp->n_outbuf = 0;
-       hp->tty = NULL;
-
-       spin_unlock_irqrestore(&hp->lock, flags);
-
-       if (hp->ops->notifier_hangup)
-               hp->ops->notifier_hangup(hp, hp->data);
-
-       while(temp_open_count) {
-               --temp_open_count;
-               tty_kref_put(tty);
-               kref_put(&hp->kref, destroy_hvc_struct);
-       }
-}
-
-/*
- * Push buffered characters whether they were just recently buffered or waiting
- * on a blocked hypervisor.  Call this function with hp->lock held.
- */
-static int hvc_push(struct hvc_struct *hp)
-{
-       int n;
-
-       n = hp->ops->put_chars(hp->vtermno, hp->outbuf, hp->n_outbuf);
-       if (n <= 0) {
-               if (n == 0) {
-                       hp->do_wakeup = 1;
-                       return 0;
-               }
-               /* throw away output on error; this happens when
-                  there is no session connected to the vterm. */
-               hp->n_outbuf = 0;
-       } else
-               hp->n_outbuf -= n;
-       if (hp->n_outbuf > 0)
-               memmove(hp->outbuf, hp->outbuf + n, hp->n_outbuf);
-       else
-               hp->do_wakeup = 1;
-
-       return n;
-}
-
-static int hvc_write(struct tty_struct *tty, const unsigned char *buf, int count)
-{
-       struct hvc_struct *hp = tty->driver_data;
-       unsigned long flags;
-       int rsize, written = 0;
-
-       /* This write was probably executed during a tty close. */
-       if (!hp)
-               return -EPIPE;
-
-       if (hp->count <= 0)
-               return -EIO;
-
-       spin_lock_irqsave(&hp->lock, flags);
-
-       /* Push pending writes */
-       if (hp->n_outbuf > 0)
-               hvc_push(hp);
-
-       while (count > 0 && (rsize = hp->outbuf_size - hp->n_outbuf) > 0) {
-               if (rsize > count)
-                       rsize = count;
-               memcpy(hp->outbuf + hp->n_outbuf, buf, rsize);
-               count -= rsize;
-               buf += rsize;
-               hp->n_outbuf += rsize;
-               written += rsize;
-               hvc_push(hp);
-       }
-       spin_unlock_irqrestore(&hp->lock, flags);
-
-       /*
-        * Racy, but harmless, kick thread if there is still pending data.
-        */
-       if (hp->n_outbuf)
-               hvc_kick();
-
-       return written;
-}
-
-/**
- * hvc_set_winsz() - Resize the hvc tty terminal window.
- * @work:      work structure.
- *
- * The routine shall not be called within an atomic context because it
- * might sleep.
- *
- * Locking:    hp->lock
- */
-static void hvc_set_winsz(struct work_struct *work)
-{
-       struct hvc_struct *hp;
-       unsigned long hvc_flags;
-       struct tty_struct *tty;
-       struct winsize ws;
-
-       hp = container_of(work, struct hvc_struct, tty_resize);
-
-       spin_lock_irqsave(&hp->lock, hvc_flags);
-       if (!hp->tty) {
-               spin_unlock_irqrestore(&hp->lock, hvc_flags);
-               return;
-       }
-       ws  = hp->ws;
-       tty = tty_kref_get(hp->tty);
-       spin_unlock_irqrestore(&hp->lock, hvc_flags);
-
-       tty_do_resize(tty, &ws);
-       tty_kref_put(tty);
-}
-
-/*
- * This is actually a contract between the driver and the tty layer outlining
- * how much write room the driver can guarantee will be sent OR BUFFERED.  This
- * driver MUST honor the return value.
- */
-static int hvc_write_room(struct tty_struct *tty)
-{
-       struct hvc_struct *hp = tty->driver_data;
-
-       if (!hp)
-               return -1;
-
-       return hp->outbuf_size - hp->n_outbuf;
-}
-
-static int hvc_chars_in_buffer(struct tty_struct *tty)
-{
-       struct hvc_struct *hp = tty->driver_data;
-
-       if (!hp)
-               return 0;
-       return hp->n_outbuf;
-}
-
-/*
- * timeout will vary between the MIN and MAX values defined here.  By default
- * and during console activity we will use a default MIN_TIMEOUT of 10.  When
- * the console is idle, we increase the timeout value on each pass through
- * msleep until we reach the max.  This may be noticeable as a brief (average
- * one second) delay on the console before the console responds to input when
- * there has been no input for some time.
- */
-#define MIN_TIMEOUT            (10)
-#define MAX_TIMEOUT            (2000)
-static u32 timeout = MIN_TIMEOUT;
-
-#define HVC_POLL_READ  0x00000001
-#define HVC_POLL_WRITE 0x00000002
-
-int hvc_poll(struct hvc_struct *hp)
-{
-       struct tty_struct *tty;
-       int i, n, poll_mask = 0;
-       char buf[N_INBUF] __ALIGNED__;
-       unsigned long flags;
-       int read_total = 0;
-       int written_total = 0;
-
-       spin_lock_irqsave(&hp->lock, flags);
-
-       /* Push pending writes */
-       if (hp->n_outbuf > 0)
-               written_total = hvc_push(hp);
-
-       /* Reschedule us if still some write pending */
-       if (hp->n_outbuf > 0) {
-               poll_mask |= HVC_POLL_WRITE;
-               /* If hvc_push() was not able to write, sleep a few msecs */
-               timeout = (written_total) ? 0 : MIN_TIMEOUT;
-       }
-
-       /* No tty attached, just skip */
-       tty = tty_kref_get(hp->tty);
-       if (tty == NULL)
-               goto bail;
-
-       /* Now check if we can get data (are we throttled ?) */
-       if (test_bit(TTY_THROTTLED, &tty->flags))
-               goto throttled;
-
-       /* If we aren't notifier driven and aren't throttled, we always
-        * request a reschedule
-        */
-       if (!hp->irq_requested)
-               poll_mask |= HVC_POLL_READ;
-
-       /* Read data if any */
-       for (;;) {
-               int count = tty_buffer_request_room(tty, N_INBUF);
-
-               /* If flip is full, just reschedule a later read */
-               if (count == 0) {
-                       poll_mask |= HVC_POLL_READ;
-                       break;
-               }
-
-               n = hp->ops->get_chars(hp->vtermno, buf, count);
-               if (n <= 0) {
-                       /* Hangup the tty when disconnected from host */
-                       if (n == -EPIPE) {
-                               spin_unlock_irqrestore(&hp->lock, flags);
-                               tty_hangup(tty);
-                               spin_lock_irqsave(&hp->lock, flags);
-                       } else if ( n == -EAGAIN ) {
-                               /*
-                                * Some back-ends can only ensure a certain min
-                                * num of bytes read, which may be > 'count'.
-                                * Let the tty clear the flip buff to make room.
-                                */
-                               poll_mask |= HVC_POLL_READ;
-                       }
-                       break;
-               }
-               for (i = 0; i < n; ++i) {
-#ifdef CONFIG_MAGIC_SYSRQ
-                       if (hp->index == hvc_console.index) {
-                               /* Handle the SysRq Hack */
-                               /* XXX should support a sequence */
-                               if (buf[i] == '\x0f') { /* ^O */
-                                       /* if ^O is pressed again, reset
-                                        * sysrq_pressed and flip ^O char */
-                                       sysrq_pressed = !sysrq_pressed;
-                                       if (sysrq_pressed)
-                                               continue;
-                               } else if (sysrq_pressed) {
-                                       handle_sysrq(buf[i]);
-                                       sysrq_pressed = 0;
-                                       continue;
-                               }
-                       }
-#endif /* CONFIG_MAGIC_SYSRQ */
-                       tty_insert_flip_char(tty, buf[i], 0);
-               }
-
-               read_total += n;
-       }
- throttled:
-       /* Wakeup write queue if necessary */
-       if (hp->do_wakeup) {
-               hp->do_wakeup = 0;
-               tty_wakeup(tty);
-       }
- bail:
-       spin_unlock_irqrestore(&hp->lock, flags);
-
-       if (read_total) {
-               /* Activity is occurring, so reset the polling backoff value to
-                  a minimum for performance. */
-               timeout = MIN_TIMEOUT;
-
-               tty_flip_buffer_push(tty);
-       }
-       if (tty)
-               tty_kref_put(tty);
-
-       return poll_mask;
-}
-EXPORT_SYMBOL_GPL(hvc_poll);
-
-/**
- * __hvc_resize() - Update terminal window size information.
- * @hp:                HVC console pointer
- * @ws:                Terminal window size structure
- *
- * Stores the specified window size information in the hvc structure of @hp.
- * The function schedule the tty resize update.
- *
- * Locking:    Locking free; the function MUST be called holding hp->lock
- */
-void __hvc_resize(struct hvc_struct *hp, struct winsize ws)
-{
-       hp->ws = ws;
-       schedule_work(&hp->tty_resize);
-}
-EXPORT_SYMBOL_GPL(__hvc_resize);
-
-/*
- * This kthread is either polling or interrupt driven.  This is determined by
- * calling hvc_poll() who determines whether a console adapter support
- * interrupts.
- */
-static int khvcd(void *unused)
-{
-       int poll_mask;
-       struct hvc_struct *hp;
-
-       set_freezable();
-       do {
-               poll_mask = 0;
-               hvc_kicked = 0;
-               try_to_freeze();
-               wmb();
-               if (!cpus_are_in_xmon()) {
-                       spin_lock(&hvc_structs_lock);
-                       list_for_each_entry(hp, &hvc_structs, next) {
-                               poll_mask |= hvc_poll(hp);
-                       }
-                       spin_unlock(&hvc_structs_lock);
-               } else
-                       poll_mask |= HVC_POLL_READ;
-               if (hvc_kicked)
-                       continue;
-               set_current_state(TASK_INTERRUPTIBLE);
-               if (!hvc_kicked) {
-                       if (poll_mask == 0)
-                               schedule();
-                       else {
-                               if (timeout < MAX_TIMEOUT)
-                                       timeout += (timeout >> 6) + 1;
-
-                               msleep_interruptible(timeout);
-                       }
-               }
-               __set_current_state(TASK_RUNNING);
-       } while (!kthread_should_stop());
-
-       return 0;
-}
-
-static const struct tty_operations hvc_ops = {
-       .open = hvc_open,
-       .close = hvc_close,
-       .write = hvc_write,
-       .hangup = hvc_hangup,
-       .unthrottle = hvc_unthrottle,
-       .write_room = hvc_write_room,
-       .chars_in_buffer = hvc_chars_in_buffer,
-};
-
-struct hvc_struct *hvc_alloc(uint32_t vtermno, int data,
-                            const struct hv_ops *ops,
-                            int outbuf_size)
-{
-       struct hvc_struct *hp;
-       int i;
-
-       /* We wait until a driver actually comes along */
-       if (!hvc_driver) {
-               int err = hvc_init();
-               if (err)
-                       return ERR_PTR(err);
-       }
-
-       hp = kzalloc(ALIGN(sizeof(*hp), sizeof(long)) + outbuf_size,
-                       GFP_KERNEL);
-       if (!hp)
-               return ERR_PTR(-ENOMEM);
-
-       hp->vtermno = vtermno;
-       hp->data = data;
-       hp->ops = ops;
-       hp->outbuf_size = outbuf_size;
-       hp->outbuf = &((char *)hp)[ALIGN(sizeof(*hp), sizeof(long))];
-
-       kref_init(&hp->kref);
-
-       INIT_WORK(&hp->tty_resize, hvc_set_winsz);
-       spin_lock_init(&hp->lock);
-       spin_lock(&hvc_structs_lock);
-
-       /*
-        * find index to use:
-        * see if this vterm id matches one registered for console.
-        */
-       for (i=0; i < MAX_NR_HVC_CONSOLES; i++)
-               if (vtermnos[i] == hp->vtermno &&
-                   cons_ops[i] == hp->ops)
-                       break;
-
-       /* no matching slot, just use a counter */
-       if (i >= MAX_NR_HVC_CONSOLES)
-               i = ++last_hvc;
-
-       hp->index = i;
-
-       list_add_tail(&(hp->next), &hvc_structs);
-       spin_unlock(&hvc_structs_lock);
-
-       return hp;
-}
-EXPORT_SYMBOL_GPL(hvc_alloc);
-
-int hvc_remove(struct hvc_struct *hp)
-{
-       unsigned long flags;
-       struct tty_struct *tty;
-
-       spin_lock_irqsave(&hp->lock, flags);
-       tty = tty_kref_get(hp->tty);
-
-       if (hp->index < MAX_NR_HVC_CONSOLES)
-               vtermnos[hp->index] = -1;
-
-       /* Don't whack hp->irq because tty_hangup() will need to free the irq. */
-
-       spin_unlock_irqrestore(&hp->lock, flags);
-
-       /*
-        * We 'put' the instance that was grabbed when the kref instance
-        * was initialized using kref_init().  Let the last holder of this
-        * kref cause it to be removed, which will probably be the tty_vhangup
-        * below.
-        */
-       kref_put(&hp->kref, destroy_hvc_struct);
-
-       /*
-        * This function call will auto chain call hvc_hangup.
-        */
-       if (tty) {
-               tty_vhangup(tty);
-               tty_kref_put(tty);
-       }
-       return 0;
-}
-EXPORT_SYMBOL_GPL(hvc_remove);
-
-/* Driver initialization: called as soon as someone uses hvc_alloc(). */
-static int hvc_init(void)
-{
-       struct tty_driver *drv;
-       int err;
-
-       /* We need more than hvc_count adapters due to hotplug additions. */
-       drv = alloc_tty_driver(HVC_ALLOC_TTY_ADAPTERS);
-       if (!drv) {
-               err = -ENOMEM;
-               goto out;
-       }
-
-       drv->owner = THIS_MODULE;
-       drv->driver_name = "hvc";
-       drv->name = "hvc";
-       drv->major = HVC_MAJOR;
-       drv->minor_start = HVC_MINOR;
-       drv->type = TTY_DRIVER_TYPE_SYSTEM;
-       drv->init_termios = tty_std_termios;
-       drv->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_RESET_TERMIOS;
-       tty_set_operations(drv, &hvc_ops);
-
-       /* Always start the kthread because there can be hotplug vty adapters
-        * added later. */
-       hvc_task = kthread_run(khvcd, NULL, "khvcd");
-       if (IS_ERR(hvc_task)) {
-               printk(KERN_ERR "Couldn't create kthread for console.\n");
-               err = PTR_ERR(hvc_task);
-               goto put_tty;
-       }
-
-       err = tty_register_driver(drv);
-       if (err) {
-               printk(KERN_ERR "Couldn't register hvc console driver\n");
-               goto stop_thread;
-       }
-
-       /*
-        * Make sure tty is fully registered before allowing it to be
-        * found by hvc_console_device.
-        */
-       smp_mb();
-       hvc_driver = drv;
-       return 0;
-
-stop_thread:
-       kthread_stop(hvc_task);
-       hvc_task = NULL;
-put_tty:
-       put_tty_driver(drv);
-out:
-       return err;
-}
-
-/* This isn't particularly necessary due to this being a console driver
- * but it is nice to be thorough.
- */
-static void __exit hvc_exit(void)
-{
-       if (hvc_driver) {
-               kthread_stop(hvc_task);
-
-               tty_unregister_driver(hvc_driver);
-               /* return tty_struct instances allocated in hvc_init(). */
-               put_tty_driver(hvc_driver);
-               unregister_console(&hvc_console);
-       }
-}
-module_exit(hvc_exit);
diff --git a/drivers/char/hvc_console.h b/drivers/char/hvc_console.h
deleted file mode 100644 (file)
index 54381eb..0000000
+++ /dev/null
@@ -1,119 +0,0 @@
-/*
- * hvc_console.h
- * Copyright (C) 2005 IBM Corporation
- *
- * Author(s):
- *     Ryan S. Arnold <rsa@us.ibm.com>
- *
- * hvc_console header information:
- *      moved here from arch/powerpc/include/asm/hvconsole.h
- *      and drivers/char/hvc_console.c
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
- */
-
-#ifndef HVC_CONSOLE_H
-#define HVC_CONSOLE_H
-#include <linux/kref.h>
-#include <linux/tty.h>
-#include <linux/spinlock.h>
-
-/*
- * This is the max number of console adapters that can/will be found as
- * console devices on first stage console init.  Any number beyond this range
- * can't be used as a console device but is still a valid tty device.
- */
-#define MAX_NR_HVC_CONSOLES    16
-
-/*
- * The Linux TTY code does not support dynamic addition of tty derived devices
- * so we need to know how many tty devices we might need when space is allocated
- * for the tty device.  Since this driver supports hotplug of vty adapters we
- * need to make sure we have enough allocated.
- */
-#define HVC_ALLOC_TTY_ADAPTERS 8
-
-struct hvc_struct {
-       spinlock_t lock;
-       int index;
-       struct tty_struct *tty;
-       int count;
-       int do_wakeup;
-       char *outbuf;
-       int outbuf_size;
-       int n_outbuf;
-       uint32_t vtermno;
-       const struct hv_ops *ops;
-       int irq_requested;
-       int data;
-       struct winsize ws;
-       struct work_struct tty_resize;
-       struct list_head next;
-       struct kref kref; /* ref count & hvc_struct lifetime */
-};
-
-/* implemented by a low level driver */
-struct hv_ops {
-       int (*get_chars)(uint32_t vtermno, char *buf, int count);
-       int (*put_chars)(uint32_t vtermno, const char *buf, int count);
-
-       /* Callbacks for notification. Called in open, close and hangup */
-       int (*notifier_add)(struct hvc_struct *hp, int irq);
-       void (*notifier_del)(struct hvc_struct *hp, int irq);
-       void (*notifier_hangup)(struct hvc_struct *hp, int irq);
-};
-
-/* Register a vterm and a slot index for use as a console (console_init) */
-extern int hvc_instantiate(uint32_t vtermno, int index,
-                          const struct hv_ops *ops);
-
-/* register a vterm for hvc tty operation (module_init or hotplug add) */
-extern struct hvc_struct * hvc_alloc(uint32_t vtermno, int data,
-                                    const struct hv_ops *ops, int outbuf_size);
-/* remove a vterm from hvc tty operation (module_exit or hotplug remove) */
-extern int hvc_remove(struct hvc_struct *hp);
-
-/* data available */
-int hvc_poll(struct hvc_struct *hp);
-void hvc_kick(void);
-
-/* Resize hvc tty terminal window */
-extern void __hvc_resize(struct hvc_struct *hp, struct winsize ws);
-
-static inline void hvc_resize(struct hvc_struct *hp, struct winsize ws)
-{
-       unsigned long flags;
-
-       spin_lock_irqsave(&hp->lock, flags);
-       __hvc_resize(hp, ws);
-       spin_unlock_irqrestore(&hp->lock, flags);
-}
-
-/* default notifier for irq based notification */
-extern int notifier_add_irq(struct hvc_struct *hp, int data);
-extern void notifier_del_irq(struct hvc_struct *hp, int data);
-extern void notifier_hangup_irq(struct hvc_struct *hp, int data);
-
-
-#if defined(CONFIG_XMON) && defined(CONFIG_SMP)
-#include <asm/xmon.h>
-#else
-static inline int cpus_are_in_xmon(void)
-{
-       return 0;
-}
-#endif
-
-#endif // HVC_CONSOLE_H
diff --git a/drivers/char/hvc_dcc.c b/drivers/char/hvc_dcc.c
deleted file mode 100644 (file)
index 6470f63..0000000
+++ /dev/null
@@ -1,133 +0,0 @@
-/* Copyright (c) 2010, Code Aurora Forum. All rights reserved.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 and
- * only version 2 as published by the Free Software Foundation.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
- * 02110-1301, USA.
- */
-
-#include <linux/console.h>
-#include <linux/delay.h>
-#include <linux/err.h>
-#include <linux/init.h>
-#include <linux/moduleparam.h>
-#include <linux/types.h>
-
-#include <asm/processor.h>
-
-#include "hvc_console.h"
-
-/* DCC Status Bits */
-#define DCC_STATUS_RX          (1 << 30)
-#define DCC_STATUS_TX          (1 << 29)
-
-static inline u32 __dcc_getstatus(void)
-{
-       u32 __ret;
-
-       asm("mrc p14, 0, %0, c0, c1, 0  @ read comms ctrl reg"
-               : "=r" (__ret) : : "cc");
-
-       return __ret;
-}
-
-
-#if defined(CONFIG_CPU_V7)
-static inline char __dcc_getchar(void)
-{
-       char __c;
-
-       asm("get_wait:  mrc p14, 0, pc, c0, c1, 0                          \n\
-                       bne get_wait                                       \n\
-                       mrc p14, 0, %0, c0, c5, 0       @ read comms data reg"
-               : "=r" (__c) : : "cc");
-
-       return __c;
-}
-#else
-static inline char __dcc_getchar(void)
-{
-       char __c;
-
-       asm("mrc p14, 0, %0, c0, c5, 0  @ read comms data reg"
-               : "=r" (__c));
-
-       return __c;
-}
-#endif
-
-#if defined(CONFIG_CPU_V7)
-static inline void __dcc_putchar(char c)
-{
-       asm("put_wait:  mrc p14, 0, pc, c0, c1, 0                 \n\
-                       bcs put_wait                              \n\
-                       mcr p14, 0, %0, c0, c5, 0                   "
-       : : "r" (c) : "cc");
-}
-#else
-static inline void __dcc_putchar(char c)
-{
-       asm("mcr p14, 0, %0, c0, c5, 0  @ write a char"
-               : /* no output register */
-               : "r" (c));
-}
-#endif
-
-static int hvc_dcc_put_chars(uint32_t vt, const char *buf, int count)
-{
-       int i;
-
-       for (i = 0; i < count; i++) {
-               while (__dcc_getstatus() & DCC_STATUS_TX)
-                       cpu_relax();
-
-               __dcc_putchar((char)(buf[i] & 0xFF));
-       }
-
-       return count;
-}
-
-static int hvc_dcc_get_chars(uint32_t vt, char *buf, int count)
-{
-       int i;
-
-       for (i = 0; i < count; ++i) {
-               int c = -1;
-
-               if (__dcc_getstatus() & DCC_STATUS_RX)
-                       c = __dcc_getchar();
-               if (c < 0)
-                       break;
-               buf[i] = c;
-       }
-
-       return i;
-}
-
-static const struct hv_ops hvc_dcc_get_put_ops = {
-       .get_chars = hvc_dcc_get_chars,
-       .put_chars = hvc_dcc_put_chars,
-};
-
-static int __init hvc_dcc_console_init(void)
-{
-       hvc_instantiate(0, 0, &hvc_dcc_get_put_ops);
-       return 0;
-}
-console_initcall(hvc_dcc_console_init);
-
-static int __init hvc_dcc_init(void)
-{
-       hvc_alloc(0, 0, &hvc_dcc_get_put_ops, 128);
-       return 0;
-}
-device_initcall(hvc_dcc_init);
diff --git a/drivers/char/hvc_irq.c b/drivers/char/hvc_irq.c
deleted file mode 100644 (file)
index 2623e17..0000000
+++ /dev/null
@@ -1,49 +0,0 @@
-/*
- * Copyright IBM Corp. 2001,2008
- *
- * This file contains the IRQ specific code for hvc_console
- *
- */
-
-#include <linux/interrupt.h>
-
-#include "hvc_console.h"
-
-static irqreturn_t hvc_handle_interrupt(int irq, void *dev_instance)
-{
-       /* if hvc_poll request a repoll, then kick the hvcd thread */
-       if (hvc_poll(dev_instance))
-               hvc_kick();
-       return IRQ_HANDLED;
-}
-
-/*
- * For IRQ based systems these callbacks can be used
- */
-int notifier_add_irq(struct hvc_struct *hp, int irq)
-{
-       int rc;
-
-       if (!irq) {
-               hp->irq_requested = 0;
-               return 0;
-       }
-       rc = request_irq(irq, hvc_handle_interrupt, IRQF_DISABLED,
-                          "hvc_console", hp);
-       if (!rc)
-               hp->irq_requested = 1;
-       return rc;
-}
-
-void notifier_del_irq(struct hvc_struct *hp, int irq)
-{
-       if (!hp->irq_requested)
-               return;
-       free_irq(irq, hp);
-       hp->irq_requested = 0;
-}
-
-void notifier_hangup_irq(struct hvc_struct *hp, int irq)
-{
-       notifier_del_irq(hp, irq);
-}
diff --git a/drivers/char/hvc_iseries.c b/drivers/char/hvc_iseries.c
deleted file mode 100644 (file)
index 21c5495..0000000
+++ /dev/null
@@ -1,598 +0,0 @@
-/*
- * iSeries vio driver interface to hvc_console.c
- *
- * This code is based heavily on hvc_vio.c and viocons.c
- *
- * Copyright (C) 2006 Stephen Rothwell, IBM Corporation
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
- */
-#include <stdarg.h>
-#include <linux/types.h>
-#include <linux/init.h>
-#include <linux/kernel.h>
-#include <linux/spinlock.h>
-#include <linux/console.h>
-
-#include <asm/hvconsole.h>
-#include <asm/vio.h>
-#include <asm/prom.h>
-#include <asm/firmware.h>
-#include <asm/iseries/vio.h>
-#include <asm/iseries/hv_call.h>
-#include <asm/iseries/hv_lp_config.h>
-#include <asm/iseries/hv_lp_event.h>
-
-#include "hvc_console.h"
-
-#define VTTY_PORTS 10
-
-static DEFINE_SPINLOCK(consolelock);
-static DEFINE_SPINLOCK(consoleloglock);
-
-static const char hvc_driver_name[] = "hvc_console";
-
-#define IN_BUF_SIZE    200
-
-/*
- * Our port information.
- */
-static struct port_info {
-       HvLpIndex lp;
-       u64 seq;        /* sequence number of last HV send */
-       u64 ack;        /* last ack from HV */
-       struct hvc_struct *hp;
-       int in_start;
-       int in_end;
-       unsigned char in_buf[IN_BUF_SIZE];
-} port_info[VTTY_PORTS] = {
-       [ 0 ... VTTY_PORTS - 1 ] = {
-               .lp = HvLpIndexInvalid
-       }
-};
-
-#define viochar_is_console(pi) ((pi) == &port_info[0])
-
-static struct vio_device_id hvc_driver_table[] __devinitdata = {
-       {"serial", "IBM,iSeries-vty"},
-       { "", "" }
-};
-MODULE_DEVICE_TABLE(vio, hvc_driver_table);
-
-static void hvlog(char *fmt, ...)
-{
-       int i;
-       unsigned long flags;
-       va_list args;
-       static char buf[256];
-
-       spin_lock_irqsave(&consoleloglock, flags);
-       va_start(args, fmt);
-       i = vscnprintf(buf, sizeof(buf) - 1, fmt, args);
-       va_end(args);
-       buf[i++] = '\r';
-       HvCall_writeLogBuffer(buf, i);
-       spin_unlock_irqrestore(&consoleloglock, flags);
-}
-
-/*
- * Initialize the common fields in a charLpEvent
- */
-static void init_data_event(struct viocharlpevent *viochar, HvLpIndex lp)
-{
-       struct HvLpEvent *hev = &viochar->event;
-
-       memset(viochar, 0, sizeof(struct viocharlpevent));
-
-       hev->flags = HV_LP_EVENT_VALID | HV_LP_EVENT_DEFERRED_ACK |
-               HV_LP_EVENT_INT;
-       hev->xType = HvLpEvent_Type_VirtualIo;
-       hev->xSubtype = viomajorsubtype_chario | viochardata;
-       hev->xSourceLp = HvLpConfig_getLpIndex();
-       hev->xTargetLp = lp;
-       hev->xSizeMinus1 = sizeof(struct viocharlpevent);
-       hev->xSourceInstanceId = viopath_sourceinst(lp);
-       hev->xTargetInstanceId = viopath_targetinst(lp);
-}
-
-static int get_chars(uint32_t vtermno, char *buf, int count)
-{
-       struct port_info *pi;
-       int n = 0;
-       unsigned long flags;
-
-       if (vtermno >= VTTY_PORTS)
-               return -EINVAL;
-       if (count == 0)
-               return 0;
-
-       pi = &port_info[vtermno];
-       spin_lock_irqsave(&consolelock, flags);
-
-       if (pi->in_end == 0)
-               goto done;
-
-       n = pi->in_end - pi->in_start;
-       if (n > count)
-               n = count;
-       memcpy(buf, &pi->in_buf[pi->in_start], n);
-       pi->in_start += n;
-       if (pi->in_start == pi->in_end) {
-               pi->in_start = 0;
-               pi->in_end = 0;
-       }
-done:
-       spin_unlock_irqrestore(&consolelock, flags);
-       return n;
-}
-
-static int put_chars(uint32_t vtermno, const char *buf, int count)
-{
-       struct viocharlpevent *viochar;
-       struct port_info *pi;
-       HvLpEvent_Rc hvrc;
-       unsigned long flags;
-       int sent = 0;
-
-       if (vtermno >= VTTY_PORTS)
-               return -EINVAL;
-
-       pi = &port_info[vtermno];
-
-       spin_lock_irqsave(&consolelock, flags);
-
-       if (viochar_is_console(pi) && !viopath_isactive(pi->lp)) {
-               HvCall_writeLogBuffer(buf, count);
-               sent = count;
-               goto done;
-       }
-
-       viochar = vio_get_event_buffer(viomajorsubtype_chario);
-       if (viochar == NULL) {
-               hvlog("\n\rviocons: Can't get viochar buffer.");
-               goto done;
-       }
-
-       while ((count > 0) && ((pi->seq - pi->ack) < VIOCHAR_WINDOW)) {
-               int len;
-
-               len = (count > VIOCHAR_MAX_DATA) ? VIOCHAR_MAX_DATA : count;
-
-               if (viochar_is_console(pi))
-                       HvCall_writeLogBuffer(buf, len);
-
-               init_data_event(viochar, pi->lp);
-
-               viochar->len = len;
-               viochar->event.xCorrelationToken = pi->seq++;
-               viochar->event.xSizeMinus1 =
-                       offsetof(struct viocharlpevent, data) + len;
-
-               memcpy(viochar->data, buf, len);
-
-               hvrc = HvCallEvent_signalLpEvent(&viochar->event);
-               if (hvrc)
-                       hvlog("\n\rerror sending event! return code %d\n\r",
-                               (int)hvrc);
-               sent += len;
-               count -= len;
-               buf += len;
-       }
-
-       vio_free_event_buffer(viomajorsubtype_chario, viochar);
-done:
-       spin_unlock_irqrestore(&consolelock, flags);
-       return sent;
-}
-
-static const struct hv_ops hvc_get_put_ops = {
-       .get_chars = get_chars,
-       .put_chars = put_chars,
-       .notifier_add = notifier_add_irq,
-       .notifier_del = notifier_del_irq,
-       .notifier_hangup = notifier_hangup_irq,
-};
-
-static int __devinit hvc_vio_probe(struct vio_dev *vdev,
-                       const struct vio_device_id *id)
-{
-       struct hvc_struct *hp;
-       struct port_info *pi;
-
-       /* probed with invalid parameters. */
-       if (!vdev || !id)
-               return -EPERM;
-
-       if (vdev->unit_address >= VTTY_PORTS)
-               return -ENODEV;
-
-       pi = &port_info[vdev->unit_address];
-
-       hp = hvc_alloc(vdev->unit_address, vdev->irq, &hvc_get_put_ops,
-                       VIOCHAR_MAX_DATA);
-       if (IS_ERR(hp))
-               return PTR_ERR(hp);
-       pi->hp = hp;
-       dev_set_drvdata(&vdev->dev, pi);
-
-       return 0;
-}
-
-static int __devexit hvc_vio_remove(struct vio_dev *vdev)
-{
-       struct port_info *pi = dev_get_drvdata(&vdev->dev);
-       struct hvc_struct *hp = pi->hp;
-
-       return hvc_remove(hp);
-}
-
-static struct vio_driver hvc_vio_driver = {
-       .id_table       = hvc_driver_table,
-       .probe          = hvc_vio_probe,
-       .remove         = __devexit_p(hvc_vio_remove),
-       .driver         = {
-               .name   = hvc_driver_name,
-               .owner  = THIS_MODULE,
-       }
-};
-
-static void hvc_open_event(struct HvLpEvent *event)
-{
-       unsigned long flags;
-       struct viocharlpevent *cevent = (struct viocharlpevent *)event;
-       u8 port = cevent->virtual_device;
-       struct port_info *pi;
-       int reject = 0;
-
-       if (hvlpevent_is_ack(event)) {
-               if (port >= VTTY_PORTS)
-                       return;
-
-               spin_lock_irqsave(&consolelock, flags);
-
-               pi = &port_info[port];
-               if (event->xRc == HvLpEvent_Rc_Good) {
-                       pi->seq = pi->ack = 0;
-                       /*
-                        * This line allows connections from the primary
-                        * partition but once one is connected from the
-                        * primary partition nothing short of a reboot
-                        * of linux will allow access from the hosting
-                        * partition again without a required iSeries fix.
-                        */
-                       pi->lp = event->xTargetLp;
-               }
-
-               spin_unlock_irqrestore(&consolelock, flags);
-               if (event->xRc != HvLpEvent_Rc_Good)
-                       printk(KERN_WARNING
-                              "hvc: handle_open_event: event->xRc == (%d).\n",
-                              event->xRc);
-
-               if (event->xCorrelationToken != 0) {
-                       atomic_t *aptr= (atomic_t *)event->xCorrelationToken;
-                       atomic_set(aptr, 1);
-               } else
-                       printk(KERN_WARNING
-                              "hvc: weird...got open ack without atomic\n");
-               return;
-       }
-
-       /* This had better require an ack, otherwise complain */
-       if (!hvlpevent_need_ack(event)) {
-               printk(KERN_WARNING "hvc: viocharopen without ack bit!\n");
-               return;
-       }
-
-       spin_lock_irqsave(&consolelock, flags);
-
-       /* Make sure this is a good virtual tty */
-       if (port >= VTTY_PORTS) {
-               event->xRc = HvLpEvent_Rc_SubtypeError;
-               cevent->subtype_result_code = viorc_openRejected;
-               /*
-                * Flag state here since we can't printk while holding
-                * the consolelock spinlock.
-                */
-               reject = 1;
-       } else {
-               pi = &port_info[port];
-               if ((pi->lp != HvLpIndexInvalid) &&
-                               (pi->lp != event->xSourceLp)) {
-                       /*
-                        * If this is tty is already connected to a different
-                        * partition, fail.
-                        */
-                       event->xRc = HvLpEvent_Rc_SubtypeError;
-                       cevent->subtype_result_code = viorc_openRejected;
-                       reject = 2;
-               } else {
-                       pi->lp = event->xSourceLp;
-                       event->xRc = HvLpEvent_Rc_Good;
-                       cevent->subtype_result_code = viorc_good;
-                       pi->seq = pi->ack = 0;
-               }
-       }
-
-       spin_unlock_irqrestore(&consolelock, flags);
-
-       if (reject == 1)
-               printk(KERN_WARNING "hvc: open rejected: bad virtual tty.\n");
-       else if (reject == 2)
-               printk(KERN_WARNING "hvc: open rejected: console in exclusive "
-                               "use by another partition.\n");
-
-       /* Return the acknowledgement */
-       HvCallEvent_ackLpEvent(event);
-}
-
-/*
- * Handle a close charLpEvent.  This should ONLY be an Interrupt because the
- * virtual console should never actually issue a close event to the hypervisor
- * because the virtual console never goes away.  A close event coming from the
- * hypervisor simply means that there are no client consoles connected to the
- * virtual console.
- */
-static void hvc_close_event(struct HvLpEvent *event)
-{
-       unsigned long flags;
-       struct viocharlpevent *cevent = (struct viocharlpevent *)event;
-       u8 port = cevent->virtual_device;
-
-       if (!hvlpevent_is_int(event)) {
-               printk(KERN_WARNING
-                       "hvc: got unexpected close acknowledgement\n");
-               return;
-       }
-
-       if (port >= VTTY_PORTS) {
-               printk(KERN_WARNING
-                       "hvc: close message from invalid virtual device.\n");
-               return;
-       }
-
-       /* For closes, just mark the console partition invalid */
-       spin_lock_irqsave(&consolelock, flags);
-
-       if (port_info[port].lp == event->xSourceLp)
-               port_info[port].lp = HvLpIndexInvalid;
-
-       spin_unlock_irqrestore(&consolelock, flags);
-}
-
-static void hvc_data_event(struct HvLpEvent *event)
-{
-       unsigned long flags;
-       struct viocharlpevent *cevent = (struct viocharlpevent *)event;
-       struct port_info *pi;
-       int n;
-       u8 port = cevent->virtual_device;
-
-       if (port >= VTTY_PORTS) {
-               printk(KERN_WARNING "hvc: data on invalid virtual device %d\n",
-                               port);
-               return;
-       }
-       if (cevent->len == 0)
-               return;
-
-       /*
-        * Change 05/01/2003 - Ryan Arnold: If a partition other than
-        * the current exclusive partition tries to send us data
-        * events then just drop them on the floor because we don't
-        * want his stinking data.  He isn't authorized to receive
-        * data because he wasn't the first one to get the console,
-        * therefore he shouldn't be allowed to send data either.
-        * This will work without an iSeries fix.
-        */
-       pi = &port_info[port];
-       if (pi->lp != event->xSourceLp)
-               return;
-
-       spin_lock_irqsave(&consolelock, flags);
-
-       n = IN_BUF_SIZE - pi->in_end;
-       if (n > cevent->len)
-               n = cevent->len;
-       if (n > 0) {
-               memcpy(&pi->in_buf[pi->in_end], cevent->data, n);
-               pi->in_end += n;
-       }
-       spin_unlock_irqrestore(&consolelock, flags);
-       if (n == 0)
-               printk(KERN_WARNING "hvc: input buffer overflow\n");
-}
-
-static void hvc_ack_event(struct HvLpEvent *event)
-{
-       struct viocharlpevent *cevent = (struct viocharlpevent *)event;
-       unsigned long flags;
-       u8 port = cevent->virtual_device;
-
-       if (port >= VTTY_PORTS) {
-               printk(KERN_WARNING "hvc: data on invalid virtual device\n");
-               return;
-       }
-
-       spin_lock_irqsave(&consolelock, flags);
-       port_info[port].ack = event->xCorrelationToken;
-       spin_unlock_irqrestore(&consolelock, flags);
-}
-
-static void hvc_config_event(struct HvLpEvent *event)
-{
-       struct viocharlpevent *cevent = (struct viocharlpevent *)event;
-
-       if (cevent->data[0] == 0x01)
-               printk(KERN_INFO "hvc: window resized to %d: %d: %d: %d\n",
-                      cevent->data[1], cevent->data[2],
-                      cevent->data[3], cevent->data[4]);
-       else
-               printk(KERN_WARNING "hvc: unknown config event\n");
-}
-
-static void hvc_handle_event(struct HvLpEvent *event)
-{
-       int charminor;
-
-       if (event == NULL)
-               return;
-
-       charminor = event->xSubtype & VIOMINOR_SUBTYPE_MASK;
-       switch (charminor) {
-       case viocharopen:
-               hvc_open_event(event);
-               break;
-       case viocharclose:
-               hvc_close_event(event);
-               break;
-       case viochardata:
-               hvc_data_event(event);
-               break;
-       case viocharack:
-               hvc_ack_event(event);
-               break;
-       case viocharconfig:
-               hvc_config_event(event);
-               break;
-       default:
-               if (hvlpevent_is_int(event) && hvlpevent_need_ack(event)) {
-                       event->xRc = HvLpEvent_Rc_InvalidSubtype;
-                       HvCallEvent_ackLpEvent(event);
-               }
-       }
-}
-
-static int __init send_open(HvLpIndex remoteLp, void *sem)
-{
-       return HvCallEvent_signalLpEventFast(remoteLp,
-                       HvLpEvent_Type_VirtualIo,
-                       viomajorsubtype_chario | viocharopen,
-                       HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
-                       viopath_sourceinst(remoteLp),
-                       viopath_targetinst(remoteLp),
-                       (u64)(unsigned long)sem, VIOVERSION << 16,
-                       0, 0, 0, 0);
-}
-
-static int __init hvc_vio_init(void)
-{
-       atomic_t wait_flag;
-       int rc;
-
-       if (!firmware_has_feature(FW_FEATURE_ISERIES))
-               return -EIO;
-
-       /* +2 for fudge */
-       rc = viopath_open(HvLpConfig_getPrimaryLpIndex(),
-                       viomajorsubtype_chario, VIOCHAR_WINDOW + 2);
-       if (rc)
-               printk(KERN_WARNING "hvc: error opening to primary %d\n", rc);
-
-       if (viopath_hostLp == HvLpIndexInvalid)
-               vio_set_hostlp();
-
-       /*
-        * And if the primary is not the same as the hosting LP, open to the
-        * hosting lp
-        */
-       if ((viopath_hostLp != HvLpIndexInvalid) &&
-           (viopath_hostLp != HvLpConfig_getPrimaryLpIndex())) {
-               printk(KERN_INFO "hvc: open path to hosting (%d)\n",
-                               viopath_hostLp);
-               rc = viopath_open(viopath_hostLp, viomajorsubtype_chario,
-                               VIOCHAR_WINDOW + 2);    /* +2 for fudge */
-               if (rc)
-                       printk(KERN_WARNING
-                               "error opening to partition %d: %d\n",
-                               viopath_hostLp, rc);
-       }
-
-       if (vio_setHandler(viomajorsubtype_chario, hvc_handle_event) < 0)
-               printk(KERN_WARNING
-                       "hvc: error seting handler for console events!\n");
-
-       /*
-        * First, try to open the console to the hosting lp.
-        * Wait on a semaphore for the response.
-        */
-       atomic_set(&wait_flag, 0);
-       if ((viopath_isactive(viopath_hostLp)) &&
-           (send_open(viopath_hostLp, &wait_flag) == 0)) {
-               printk(KERN_INFO "hvc: hosting partition %d\n", viopath_hostLp);
-               while (atomic_read(&wait_flag) == 0)
-                       mb();
-               atomic_set(&wait_flag, 0);
-       }
-
-       /*
-        * If we don't have an active console, try the primary
-        */
-       if ((!viopath_isactive(port_info[0].lp)) &&
-           (viopath_isactive(HvLpConfig_getPrimaryLpIndex())) &&
-           (send_open(HvLpConfig_getPrimaryLpIndex(), &wait_flag) == 0)) {
-               printk(KERN_INFO "hvc: opening console to primary partition\n");
-               while (atomic_read(&wait_flag) == 0)
-                       mb();
-       }
-
-       /* Register as a vio device to receive callbacks */
-       rc = vio_register_driver(&hvc_vio_driver);
-
-       return rc;
-}
-module_init(hvc_vio_init); /* after drivers/char/hvc_console.c */
-
-static void __exit hvc_vio_exit(void)
-{
-       vio_unregister_driver(&hvc_vio_driver);
-}
-module_exit(hvc_vio_exit);
-
-/* the device tree order defines our numbering */
-static int __init hvc_find_vtys(void)
-{
-       struct device_node *vty;
-       int num_found = 0;
-
-       for (vty = of_find_node_by_name(NULL, "vty"); vty != NULL;
-                       vty = of_find_node_by_name(vty, "vty")) {
-               const uint32_t *vtermno;
-
-               /* We have statically defined space for only a certain number
-                * of console adapters.
-                */
-               if ((num_found >= MAX_NR_HVC_CONSOLES) ||
-                               (num_found >= VTTY_PORTS)) {
-                       of_node_put(vty);
-                       break;
-               }
-
-               vtermno = of_get_property(vty, "reg", NULL);
-               if (!vtermno)
-                       continue;
-
-               if (!of_device_is_compatible(vty, "IBM,iSeries-vty"))
-                       continue;
-
-               if (num_found == 0)
-                       add_preferred_console("hvc", 0, NULL);
-               hvc_instantiate(*vtermno, num_found, &hvc_get_put_ops);
-               ++num_found;
-       }
-
-       return num_found;
-}
-console_initcall(hvc_find_vtys);
diff --git a/drivers/char/hvc_iucv.c b/drivers/char/hvc_iucv.c
deleted file mode 100644 (file)
index c3425bb..0000000
+++ /dev/null
@@ -1,1337 +0,0 @@
-/*
- * hvc_iucv.c - z/VM IUCV hypervisor console (HVC) device driver
- *
- * This HVC device driver provides terminal access using
- * z/VM IUCV communication paths.
- *
- * Copyright IBM Corp. 2008, 2009
- *
- * Author(s):  Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
- */
-#define KMSG_COMPONENT         "hvc_iucv"
-#define pr_fmt(fmt)            KMSG_COMPONENT ": " fmt
-
-#include <linux/types.h>
-#include <linux/slab.h>
-#include <asm/ebcdic.h>
-#include <linux/ctype.h>
-#include <linux/delay.h>
-#include <linux/device.h>
-#include <linux/init.h>
-#include <linux/mempool.h>
-#include <linux/moduleparam.h>
-#include <linux/tty.h>
-#include <linux/wait.h>
-#include <net/iucv/iucv.h>
-
-#include "hvc_console.h"
-
-
-/* General device driver settings */
-#define HVC_IUCV_MAGIC         0xc9e4c3e5
-#define MAX_HVC_IUCV_LINES     HVC_ALLOC_TTY_ADAPTERS
-#define MEMPOOL_MIN_NR         (PAGE_SIZE / sizeof(struct iucv_tty_buffer)/4)
-
-/* IUCV TTY message  */
-#define MSG_VERSION            0x02    /* Message version */
-#define MSG_TYPE_ERROR         0x01    /* Error message */
-#define MSG_TYPE_TERMENV       0x02    /* Terminal environment variable */
-#define MSG_TYPE_TERMIOS       0x04    /* Terminal IO struct update */
-#define MSG_TYPE_WINSIZE       0x08    /* Terminal window size update */
-#define MSG_TYPE_DATA          0x10    /* Terminal data */
-
-struct iucv_tty_msg {
-       u8      version;                /* Message version */
-       u8      type;                   /* Message type */
-#define MSG_MAX_DATALEN                ((u16)(~0))
-       u16     datalen;                /* Payload length */
-       u8      data[];                 /* Payload buffer */
-} __attribute__((packed));
-#define MSG_SIZE(s)            ((s) + offsetof(struct iucv_tty_msg, data))
-
-enum iucv_state_t {
-       IUCV_DISCONN    = 0,
-       IUCV_CONNECTED  = 1,
-       IUCV_SEVERED    = 2,
-};
-
-enum tty_state_t {
-       TTY_CLOSED      = 0,
-       TTY_OPENED      = 1,
-};
-
-struct hvc_iucv_private {
-       struct hvc_struct       *hvc;           /* HVC struct reference */
-       u8                      srv_name[8];    /* IUCV service name (ebcdic) */
-       unsigned char           is_console;     /* Linux console usage flag */
-       enum iucv_state_t       iucv_state;     /* IUCV connection status */
-       enum tty_state_t        tty_state;      /* TTY status */
-       struct iucv_path        *path;          /* IUCV path pointer */
-       spinlock_t              lock;           /* hvc_iucv_private lock */
-#define SNDBUF_SIZE            (PAGE_SIZE)     /* must be < MSG_MAX_DATALEN */
-       void                    *sndbuf;        /* send buffer            */
-       size_t                  sndbuf_len;     /* length of send buffer  */
-#define QUEUE_SNDBUF_DELAY     (HZ / 25)
-       struct delayed_work     sndbuf_work;    /* work: send iucv msg(s) */
-       wait_queue_head_t       sndbuf_waitq;   /* wait for send completion */
-       struct list_head        tty_outqueue;   /* outgoing IUCV messages */
-       struct list_head        tty_inqueue;    /* incoming IUCV messages */
-       struct device           *dev;           /* device structure */
-};
-
-struct iucv_tty_buffer {
-       struct list_head        list;   /* list pointer */
-       struct iucv_message     msg;    /* store an IUCV message */
-       size_t                  offset; /* data buffer offset */
-       struct iucv_tty_msg     *mbuf;  /* buffer to store input/output data */
-};
-
-/* IUCV callback handler */
-static int hvc_iucv_path_pending(struct iucv_path *, u8[8], u8[16]);
-static void hvc_iucv_path_severed(struct iucv_path *, u8[16]);
-static void hvc_iucv_msg_pending(struct iucv_path *, struct iucv_message *);
-static void hvc_iucv_msg_complete(struct iucv_path *, struct iucv_message *);
-
-
-/* Kernel module parameter: use one terminal device as default */
-static unsigned long hvc_iucv_devices = 1;
-
-/* Array of allocated hvc iucv tty lines... */
-static struct hvc_iucv_private *hvc_iucv_table[MAX_HVC_IUCV_LINES];
-#define IUCV_HVC_CON_IDX       (0)
-/* List of z/VM user ID filter entries (struct iucv_vmid_filter) */
-#define MAX_VMID_FILTER                (500)
-static size_t hvc_iucv_filter_size;
-static void *hvc_iucv_filter;
-static const char *hvc_iucv_filter_string;
-static DEFINE_RWLOCK(hvc_iucv_filter_lock);
-
-/* Kmem cache and mempool for iucv_tty_buffer elements */
-static struct kmem_cache *hvc_iucv_buffer_cache;
-static mempool_t *hvc_iucv_mempool;
-
-/* IUCV handler callback functions */
-static struct iucv_handler hvc_iucv_handler = {
-       .path_pending  = hvc_iucv_path_pending,
-       .path_severed  = hvc_iucv_path_severed,
-       .message_complete = hvc_iucv_msg_complete,
-       .message_pending  = hvc_iucv_msg_pending,
-};
-
-
-/**
- * hvc_iucv_get_private() - Return a struct hvc_iucv_private instance.
- * @num:       The HVC virtual terminal number (vtermno)
- *
- * This function returns the struct hvc_iucv_private instance that corresponds
- * to the HVC virtual terminal number specified as parameter @num.
- */
-struct hvc_iucv_private *hvc_iucv_get_private(uint32_t num)
-{
-       if ((num < HVC_IUCV_MAGIC) || (num - HVC_IUCV_MAGIC > hvc_iucv_devices))
-               return NULL;
-       return hvc_iucv_table[num - HVC_IUCV_MAGIC];
-}
-
-/**
- * alloc_tty_buffer() - Return a new struct iucv_tty_buffer element.
- * @size:      Size of the internal buffer used to store data.
- * @flags:     Memory allocation flags passed to mempool.
- *
- * This function allocates a new struct iucv_tty_buffer element and, optionally,
- * allocates an internal data buffer with the specified size @size.
- * The internal data buffer is always allocated with GFP_DMA which is
- * required for receiving and sending data with IUCV.
- * Note: The total message size arises from the internal buffer size and the
- *      members of the iucv_tty_msg structure.
- * The function returns NULL if memory allocation has failed.
- */
-static struct iucv_tty_buffer *alloc_tty_buffer(size_t size, gfp_t flags)
-{
-       struct iucv_tty_buffer *bufp;
-
-       bufp = mempool_alloc(hvc_iucv_mempool, flags);
-       if (!bufp)
-               return NULL;
-       memset(bufp, 0, sizeof(*bufp));
-
-       if (size > 0) {
-               bufp->msg.length = MSG_SIZE(size);
-               bufp->mbuf = kmalloc(bufp->msg.length, flags | GFP_DMA);
-               if (!bufp->mbuf) {
-                       mempool_free(bufp, hvc_iucv_mempool);
-                       return NULL;
-               }
-               bufp->mbuf->version = MSG_VERSION;
-               bufp->mbuf->type    = MSG_TYPE_DATA;
-               bufp->mbuf->datalen = (u16) size;
-       }
-       return bufp;
-}
-
-/**
- * destroy_tty_buffer() - destroy struct iucv_tty_buffer element.
- * @bufp:      Pointer to a struct iucv_tty_buffer element, SHALL NOT be NULL.
- */
-static void destroy_tty_buffer(struct iucv_tty_buffer *bufp)
-{
-       kfree(bufp->mbuf);
-       mempool_free(bufp, hvc_iucv_mempool);
-}
-
-/**
- * destroy_tty_buffer_list() - call destroy_tty_buffer() for each list element.
- * @list:      List containing struct iucv_tty_buffer elements.
- */
-static void destroy_tty_buffer_list(struct list_head *list)
-{
-       struct iucv_tty_buffer *ent, *next;
-
-       list_for_each_entry_safe(ent, next, list, list) {
-               list_del(&ent->list);
-               destroy_tty_buffer(ent);
-       }
-}
-
-/**
- * hvc_iucv_write() - Receive IUCV message & write data to HVC buffer.
- * @priv:              Pointer to struct hvc_iucv_private
- * @buf:               HVC buffer for writing received terminal data.
- * @count:             HVC buffer size.
- * @has_more_data:     Pointer to an int variable.
- *
- * The function picks up pending messages from the input queue and receives
- * the message data that is then written to the specified buffer @buf.
- * If the buffer size @count is less than the data message size, the
- * message is kept on the input queue and @has_more_data is set to 1.
- * If all message data has been written, the message is removed from
- * the input queue.
- *
- * The function returns the number of bytes written to the terminal, zero if
- * there are no pending data messages available or if there is no established
- * IUCV path.
- * If the IUCV path has been severed, then -EPIPE is returned to cause a
- * hang up (that is issued by the HVC layer).
- */
-static int hvc_iucv_write(struct hvc_iucv_private *priv,
-                         char *buf, int count, int *has_more_data)
-{
-       struct iucv_tty_buffer *rb;
-       int written;
-       int rc;
-
-       /* immediately return if there is no IUCV connection */
-       if (priv->iucv_state == IUCV_DISCONN)
-               return 0;
-
-       /* if the IUCV path has been severed, return -EPIPE to inform the
-        * HVC layer to hang up the tty device. */
-       if (priv->iucv_state == IUCV_SEVERED)
-               return -EPIPE;
-
-       /* check if there are pending messages */
-       if (list_empty(&priv->tty_inqueue))
-               return 0;
-
-       /* receive an iucv message and flip data to the tty (ldisc) */
-       rb = list_first_entry(&priv->tty_inqueue, struct iucv_tty_buffer, list);
-
-       written = 0;
-       if (!rb->mbuf) { /* message not yet received ... */
-               /* allocate mem to store msg data; if no memory is available
-                * then leave the buffer on the list and re-try later */
-               rb->mbuf = kmalloc(rb->msg.length, GFP_ATOMIC | GFP_DMA);
-               if (!rb->mbuf)
-                       return -ENOMEM;
-
-               rc = __iucv_message_receive(priv->path, &rb->msg, 0,
-                                           rb->mbuf, rb->msg.length, NULL);
-               switch (rc) {
-               case 0: /* Successful       */
-                       break;
-               case 2: /* No message found */
-               case 9: /* Message purged   */
-                       break;
-               default:
-                       written = -EIO;
-               }
-               /* remove buffer if an error has occured or received data
-                * is not correct */
-               if (rc || (rb->mbuf->version != MSG_VERSION) ||
-                         (rb->msg.length    != MSG_SIZE(rb->mbuf->datalen)))
-                       goto out_remove_buffer;
-       }
-
-       switch (rb->mbuf->type) {
-       case MSG_TYPE_DATA:
-               written = min_t(int, rb->mbuf->datalen - rb->offset, count);
-               memcpy(buf, rb->mbuf->data + rb->offset, written);
-               if (written < (rb->mbuf->datalen - rb->offset)) {
-                       rb->offset += written;
-                       *has_more_data = 1;
-                       goto out_written;
-               }
-               break;
-
-       case MSG_TYPE_WINSIZE:
-               if (rb->mbuf->datalen != sizeof(struct winsize))
-                       break;
-               /* The caller must ensure that the hvc is locked, which
-                * is the case when called from hvc_iucv_get_chars() */
-               __hvc_resize(priv->hvc, *((struct winsize *) rb->mbuf->data));
-               break;
-
-       case MSG_TYPE_ERROR:    /* ignored ... */
-       case MSG_TYPE_TERMENV:  /* ignored ... */
-       case MSG_TYPE_TERMIOS:  /* ignored ... */
-               break;
-       }
-
-out_remove_buffer:
-       list_del(&rb->list);
-       destroy_tty_buffer(rb);
-       *has_more_data = !list_empty(&priv->tty_inqueue);
-
-out_written:
-       return written;
-}
-
-/**
- * hvc_iucv_get_chars() - HVC get_chars operation.
- * @vtermno:   HVC virtual terminal number.
- * @buf:       Pointer to a buffer to store data
- * @count:     Size of buffer available for writing
- *
- * The HVC thread calls this method to read characters from the back-end.
- * If an IUCV communication path has been established, pending IUCV messages
- * are received and data is copied into buffer @buf up to @count bytes.
- *
- * Locking:    The routine gets called under an irqsave() spinlock; and
- *             the routine locks the struct hvc_iucv_private->lock to call
- *             helper functions.
- */
-static int hvc_iucv_get_chars(uint32_t vtermno, char *buf, int count)
-{
-       struct hvc_iucv_private *priv = hvc_iucv_get_private(vtermno);
-       int written;
-       int has_more_data;
-
-       if (count <= 0)
-               return 0;
-
-       if (!priv)
-               return -ENODEV;
-
-       spin_lock(&priv->lock);
-       has_more_data = 0;
-       written = hvc_iucv_write(priv, buf, count, &has_more_data);
-       spin_unlock(&priv->lock);
-
-       /* if there are still messages on the queue... schedule another run */
-       if (has_more_data)
-               hvc_kick();
-
-       return written;
-}
-
-/**
- * hvc_iucv_queue() - Buffer terminal data for sending.
- * @priv:      Pointer to struct hvc_iucv_private instance.
- * @buf:       Buffer containing data to send.
- * @count:     Size of buffer and amount of data to send.
- *
- * The function queues data for sending. To actually send the buffered data,
- * a work queue function is scheduled (with QUEUE_SNDBUF_DELAY).
- * The function returns the number of data bytes that has been buffered.
- *
- * If the device is not connected, data is ignored and the function returns
- * @count.
- * If the buffer is full, the function returns 0.
- * If an existing IUCV communicaton path has been severed, -EPIPE is returned
- * (that can be passed to HVC layer to cause a tty hangup).
- */
-static int hvc_iucv_queue(struct hvc_iucv_private *priv, const char *buf,
-                         int count)
-{
-       size_t len;
-
-       if (priv->iucv_state == IUCV_DISCONN)
-               return count;                   /* ignore data */
-
-       if (priv->iucv_state == IUCV_SEVERED)
-               return -EPIPE;
-
-       len = min_t(size_t, count, SNDBUF_SIZE - priv->sndbuf_len);
-       if (!len)
-               return 0;
-
-       memcpy(priv->sndbuf + priv->sndbuf_len, buf, len);
-       priv->sndbuf_len += len;
-
-       if (priv->iucv_state == IUCV_CONNECTED)
-               schedule_delayed_work(&priv->sndbuf_work, QUEUE_SNDBUF_DELAY);
-
-       return len;
-}
-
-/**
- * hvc_iucv_send() - Send an IUCV message containing terminal data.
- * @priv:      Pointer to struct hvc_iucv_private instance.
- *
- * If an IUCV communication path has been established, the buffered output data
- * is sent via an IUCV message and the number of bytes sent is returned.
- * Returns 0 if there is no established IUCV communication path or
- * -EPIPE if an existing IUCV communicaton path has been severed.
- */
-static int hvc_iucv_send(struct hvc_iucv_private *priv)
-{
-       struct iucv_tty_buffer *sb;
-       int rc, len;
-
-       if (priv->iucv_state == IUCV_SEVERED)
-               return -EPIPE;
-
-       if (priv->iucv_state == IUCV_DISCONN)
-               return -EIO;
-
-       if (!priv->sndbuf_len)
-               return 0;
-
-       /* allocate internal buffer to store msg data and also compute total
-        * message length */
-       sb = alloc_tty_buffer(priv->sndbuf_len, GFP_ATOMIC);
-       if (!sb)
-               return -ENOMEM;
-
-       memcpy(sb->mbuf->data, priv->sndbuf, priv->sndbuf_len);
-       sb->mbuf->datalen = (u16) priv->sndbuf_len;
-       sb->msg.length = MSG_SIZE(sb->mbuf->datalen);
-
-       list_add_tail(&sb->list, &priv->tty_outqueue);
-
-       rc = __iucv_message_send(priv->path, &sb->msg, 0, 0,
-                                (void *) sb->mbuf, sb->msg.length);
-       if (rc) {
-               /* drop the message here; however we might want to handle
-                * 0x03 (msg limit reached) by trying again... */
-               list_del(&sb->list);
-               destroy_tty_buffer(sb);
-       }
-       len = priv->sndbuf_len;
-       priv->sndbuf_len = 0;
-
-       return len;
-}
-
-/**
- * hvc_iucv_sndbuf_work() - Send buffered data over IUCV
- * @work:      Work structure.
- *
- * This work queue function sends buffered output data over IUCV and,
- * if not all buffered data could be sent, reschedules itself.
- */
-static void hvc_iucv_sndbuf_work(struct work_struct *work)
-{
-       struct hvc_iucv_private *priv;
-
-       priv = container_of(work, struct hvc_iucv_private, sndbuf_work.work);
-       if (!priv)
-               return;
-
-       spin_lock_bh(&priv->lock);
-       hvc_iucv_send(priv);
-       spin_unlock_bh(&priv->lock);
-}
-
-/**
- * hvc_iucv_put_chars() - HVC put_chars operation.
- * @vtermno:   HVC virtual terminal number.
- * @buf:       Pointer to an buffer to read data from
- * @count:     Size of buffer available for reading
- *
- * The HVC thread calls this method to write characters to the back-end.
- * The function calls hvc_iucv_queue() to queue terminal data for sending.
- *
- * Locking:    The method gets called under an irqsave() spinlock; and
- *             locks struct hvc_iucv_private->lock.
- */
-static int hvc_iucv_put_chars(uint32_t vtermno, const char *buf, int count)
-{
-       struct hvc_iucv_private *priv = hvc_iucv_get_private(vtermno);
-       int queued;
-
-       if (count <= 0)
-               return 0;
-
-       if (!priv)
-               return -ENODEV;
-
-       spin_lock(&priv->lock);
-       queued = hvc_iucv_queue(priv, buf, count);
-       spin_unlock(&priv->lock);
-
-       return queued;
-}
-
-/**
- * hvc_iucv_notifier_add() - HVC notifier for opening a TTY for the first time.
- * @hp:        Pointer to the HVC device (struct hvc_struct)
- * @id:        Additional data (originally passed to hvc_alloc): the index of an struct
- *     hvc_iucv_private instance.
- *
- * The function sets the tty state to TTY_OPENED for the struct hvc_iucv_private
- * instance that is derived from @id. Always returns 0.
- *
- * Locking:    struct hvc_iucv_private->lock, spin_lock_bh
- */
-static int hvc_iucv_notifier_add(struct hvc_struct *hp, int id)
-{
-       struct hvc_iucv_private *priv;
-
-       priv = hvc_iucv_get_private(id);
-       if (!priv)
-               return 0;
-
-       spin_lock_bh(&priv->lock);
-       priv->tty_state = TTY_OPENED;
-       spin_unlock_bh(&priv->lock);
-
-       return 0;
-}
-
-/**
- * hvc_iucv_cleanup() - Clean up and reset a z/VM IUCV HVC instance.
- * @priv:      Pointer to the struct hvc_iucv_private instance.
- */
-static void hvc_iucv_cleanup(struct hvc_iucv_private *priv)
-{
-       destroy_tty_buffer_list(&priv->tty_outqueue);
-       destroy_tty_buffer_list(&priv->tty_inqueue);
-
-       priv->tty_state = TTY_CLOSED;
-       priv->iucv_state = IUCV_DISCONN;
-
-       priv->sndbuf_len = 0;
-}
-
-/**
- * tty_outqueue_empty() - Test if the tty outq is empty
- * @priv:      Pointer to struct hvc_iucv_private instance.
- */
-static inline int tty_outqueue_empty(struct hvc_iucv_private *priv)
-{
-       int rc;
-
-       spin_lock_bh(&priv->lock);
-       rc = list_empty(&priv->tty_outqueue);
-       spin_unlock_bh(&priv->lock);
-
-       return rc;
-}
-
-/**
- * flush_sndbuf_sync() - Flush send buffer and wait for completion
- * @priv:      Pointer to struct hvc_iucv_private instance.
- *
- * The routine cancels a pending sndbuf work, calls hvc_iucv_send()
- * to flush any buffered terminal output data and waits for completion.
- */
-static void flush_sndbuf_sync(struct hvc_iucv_private *priv)
-{
-       int sync_wait;
-
-       cancel_delayed_work_sync(&priv->sndbuf_work);
-
-       spin_lock_bh(&priv->lock);
-       hvc_iucv_send(priv);            /* force sending buffered data */
-       sync_wait = !list_empty(&priv->tty_outqueue); /* anything queued ? */
-       spin_unlock_bh(&priv->lock);
-
-       if (sync_wait)
-               wait_event_timeout(priv->sndbuf_waitq,
-                                  tty_outqueue_empty(priv), HZ/10);
-}
-
-/**
- * hvc_iucv_hangup() - Sever IUCV path and schedule hvc tty hang up
- * @priv:      Pointer to hvc_iucv_private structure
- *
- * This routine severs an existing IUCV communication path and hangs
- * up the underlying HVC terminal device.
- * The hang-up occurs only if an IUCV communication path is established;
- * otherwise there is no need to hang up the terminal device.
- *
- * The IUCV HVC hang-up is separated into two steps:
- * 1. After the IUCV path has been severed, the iucv_state is set to
- *    IUCV_SEVERED.
- * 2. Later, when the HVC thread calls hvc_iucv_get_chars(), the
- *    IUCV_SEVERED state causes the tty hang-up in the HVC layer.
- *
- * If the tty has not yet been opened, clean up the hvc_iucv_private
- * structure to allow re-connects.
- * If the tty has been opened, let get_chars() return -EPIPE to signal
- * the HVC layer to hang up the tty and, if so, wake up the HVC thread
- * to call get_chars()...
- *
- * Special notes on hanging up a HVC terminal instantiated as console:
- * Hang-up:    1. do_tty_hangup() replaces file ops (= hung_up_tty_fops)
- *             2. do_tty_hangup() calls tty->ops->close() for console_filp
- *                     => no hangup notifier is called by HVC (default)
- *             2. hvc_close() returns because of tty_hung_up_p(filp)
- *                     => no delete notifier is called!
- * Finally, the back-end is not being notified, thus, the tty session is
- * kept active (TTY_OPEN) to be ready for re-connects.
- *
- * Locking:    spin_lock(&priv->lock) w/o disabling bh
- */
-static void hvc_iucv_hangup(struct hvc_iucv_private *priv)
-{
-       struct iucv_path *path;
-
-       path = NULL;
-       spin_lock(&priv->lock);
-       if (priv->iucv_state == IUCV_CONNECTED) {
-               path = priv->path;
-               priv->path = NULL;
-               priv->iucv_state = IUCV_SEVERED;
-               if (priv->tty_state == TTY_CLOSED)
-                       hvc_iucv_cleanup(priv);
-               else
-                       /* console is special (see above) */
-                       if (priv->is_console) {
-                               hvc_iucv_cleanup(priv);
-                               priv->tty_state = TTY_OPENED;
-                       } else
-                               hvc_kick();
-       }
-       spin_unlock(&priv->lock);
-
-       /* finally sever path (outside of priv->lock due to lock ordering) */
-       if (path) {
-               iucv_path_sever(path, NULL);
-               iucv_path_free(path);
-       }
-}
-
-/**
- * hvc_iucv_notifier_hangup() - HVC notifier for TTY hangups.
- * @hp:                Pointer to the HVC device (struct hvc_struct)
- * @id:                Additional data (originally passed to hvc_alloc):
- *             the index of an struct hvc_iucv_private instance.
- *
- * This routine notifies the HVC back-end that a tty hangup (carrier loss,
- * virtual or otherwise) has occured.
- * The z/VM IUCV HVC device driver ignores virtual hangups (vhangup())
- * to keep an existing IUCV communication path established.
- * (Background: vhangup() is called from user space (by getty or login) to
- *             disable writing to the tty by other applications).
- * If the tty has been opened and an established IUCV path has been severed
- * (we caused the tty hangup), the function calls hvc_iucv_cleanup().
- *
- * Locking:    struct hvc_iucv_private->lock
- */
-static void hvc_iucv_notifier_hangup(struct hvc_struct *hp, int id)
-{
-       struct hvc_iucv_private *priv;
-
-       priv = hvc_iucv_get_private(id);
-       if (!priv)
-               return;
-
-       flush_sndbuf_sync(priv);
-
-       spin_lock_bh(&priv->lock);
-       /* NOTE: If the hangup was scheduled by ourself (from the iucv
-        *       path_servered callback [IUCV_SEVERED]), we have to clean up
-        *       our structure and to set state to TTY_CLOSED.
-        *       If the tty was hung up otherwise (e.g. vhangup()), then we
-        *       ignore this hangup and keep an established IUCV path open...
-        *       (...the reason is that we are not able to connect back to the
-        *       client if we disconnect on hang up) */
-       priv->tty_state = TTY_CLOSED;
-
-       if (priv->iucv_state == IUCV_SEVERED)
-               hvc_iucv_cleanup(priv);
-       spin_unlock_bh(&priv->lock);
-}
-
-/**
- * hvc_iucv_notifier_del() - HVC notifier for closing a TTY for the last time.
- * @hp:                Pointer to the HVC device (struct hvc_struct)
- * @id:                Additional data (originally passed to hvc_alloc):
- *             the index of an struct hvc_iucv_private instance.
- *
- * This routine notifies the HVC back-end that the last tty device fd has been
- * closed.  The function calls hvc_iucv_cleanup() to clean up the struct
- * hvc_iucv_private instance.
- *
- * Locking:    struct hvc_iucv_private->lock
- */
-static void hvc_iucv_notifier_del(struct hvc_struct *hp, int id)
-{
-       struct hvc_iucv_private *priv;
-       struct iucv_path        *path;
-
-       priv = hvc_iucv_get_private(id);
-       if (!priv)
-               return;
-
-       flush_sndbuf_sync(priv);
-
-       spin_lock_bh(&priv->lock);
-       path = priv->path;              /* save reference to IUCV path */
-       priv->path = NULL;
-       hvc_iucv_cleanup(priv);
-       spin_unlock_bh(&priv->lock);
-
-       /* sever IUCV path outside of priv->lock due to lock ordering of:
-        * priv->lock <--> iucv_table_lock */
-       if (path) {
-               iucv_path_sever(path, NULL);
-               iucv_path_free(path);
-       }
-}
-
-/**
- * hvc_iucv_filter_connreq() - Filter connection request based on z/VM user ID
- * @ipvmid:    Originating z/VM user ID (right padded with blanks)
- *
- * Returns 0 if the z/VM user ID @ipvmid is allowed to connection, otherwise
- * non-zero.
- */
-static int hvc_iucv_filter_connreq(u8 ipvmid[8])
-{
-       size_t i;
-
-       /* Note: default policy is ACCEPT if no filter is set */
-       if (!hvc_iucv_filter_size)
-               return 0;
-
-       for (i = 0; i < hvc_iucv_filter_size; i++)
-               if (0 == memcmp(ipvmid, hvc_iucv_filter + (8 * i), 8))
-                       return 0;
-       return 1;
-}
-
-/**
- * hvc_iucv_path_pending() - IUCV handler to process a connection request.
- * @path:      Pending path (struct iucv_path)
- * @ipvmid:    z/VM system identifier of originator
- * @ipuser:    User specified data for this path
- *             (AF_IUCV: port/service name and originator port)
- *
- * The function uses the @ipuser data to determine if the pending path belongs
- * to a terminal managed by this device driver.
- * If the path belongs to this driver, ensure that the terminal is not accessed
- * multiple times (only one connection to a terminal is allowed).
- * If the terminal is not yet connected, the pending path is accepted and is
- * associated to the appropriate struct hvc_iucv_private instance.
- *
- * Returns 0 if @path belongs to a terminal managed by the this device driver;
- * otherwise returns -ENODEV in order to dispatch this path to other handlers.
- *
- * Locking:    struct hvc_iucv_private->lock
- */
-static int hvc_iucv_path_pending(struct iucv_path *path,
-                                 u8 ipvmid[8], u8 ipuser[16])
-{
-       struct hvc_iucv_private *priv;
-       u8 nuser_data[16];
-       u8 vm_user_id[9];
-       int i, rc;
-
-       priv = NULL;
-       for (i = 0; i < hvc_iucv_devices; i++)
-               if (hvc_iucv_table[i] &&
-                   (0 == memcmp(hvc_iucv_table[i]->srv_name, ipuser, 8))) {
-                       priv = hvc_iucv_table[i];
-                       break;
-               }
-       if (!priv)
-               return -ENODEV;
-
-       /* Enforce that ipvmid is allowed to connect to us */
-       read_lock(&hvc_iucv_filter_lock);
-       rc = hvc_iucv_filter_connreq(ipvmid);
-       read_unlock(&hvc_iucv_filter_lock);
-       if (rc) {
-               iucv_path_sever(path, ipuser);
-               iucv_path_free(path);
-               memcpy(vm_user_id, ipvmid, 8);
-               vm_user_id[8] = 0;
-               pr_info("A connection request from z/VM user ID %s "
-                       "was refused\n", vm_user_id);
-               return 0;
-       }
-
-       spin_lock(&priv->lock);
-
-       /* If the terminal is already connected or being severed, then sever
-        * this path to enforce that there is only ONE established communication
-        * path per terminal. */
-       if (priv->iucv_state != IUCV_DISCONN) {
-               iucv_path_sever(path, ipuser);
-               iucv_path_free(path);
-               goto out_path_handled;
-       }
-
-       /* accept path */
-       memcpy(nuser_data, ipuser + 8, 8);  /* remote service (for af_iucv) */
-       memcpy(nuser_data + 8, ipuser, 8);  /* local service  (for af_iucv) */
-       path->msglim = 0xffff;              /* IUCV MSGLIMIT */
-       path->flags &= ~IUCV_IPRMDATA;      /* TODO: use IUCV_IPRMDATA */
-       rc = iucv_path_accept(path, &hvc_iucv_handler, nuser_data, priv);
-       if (rc) {
-               iucv_path_sever(path, ipuser);
-               iucv_path_free(path);
-               goto out_path_handled;
-       }
-       priv->path = path;
-       priv->iucv_state = IUCV_CONNECTED;
-
-       /* flush buffered output data... */
-       schedule_delayed_work(&priv->sndbuf_work, 5);
-
-out_path_handled:
-       spin_unlock(&priv->lock);
-       return 0;
-}
-
-/**
- * hvc_iucv_path_severed() - IUCV handler to process a path sever.
- * @path:      Pending path (struct iucv_path)
- * @ipuser:    User specified data for this path
- *             (AF_IUCV: port/service name and originator port)
- *
- * This function calls the hvc_iucv_hangup() function for the
- * respective IUCV HVC terminal.
- *
- * Locking:    struct hvc_iucv_private->lock
- */
-static void hvc_iucv_path_severed(struct iucv_path *path, u8 ipuser[16])
-{
-       struct hvc_iucv_private *priv = path->private;
-
-       hvc_iucv_hangup(priv);
-}
-
-/**
- * hvc_iucv_msg_pending() - IUCV handler to process an incoming IUCV message.
- * @path:      Pending path (struct iucv_path)
- * @msg:       Pointer to the IUCV message
- *
- * The function puts an incoming message on the input queue for later
- * processing (by hvc_iucv_get_chars() / hvc_iucv_write()).
- * If the tty has not yet been opened, the message is rejected.
- *
- * Locking:    struct hvc_iucv_private->lock
- */
-static void hvc_iucv_msg_pending(struct iucv_path *path,
-                                struct iucv_message *msg)
-{
-       struct hvc_iucv_private *priv = path->private;
-       struct iucv_tty_buffer *rb;
-
-       /* reject messages that exceed max size of iucv_tty_msg->datalen */
-       if (msg->length > MSG_SIZE(MSG_MAX_DATALEN)) {
-               iucv_message_reject(path, msg);
-               return;
-       }
-
-       spin_lock(&priv->lock);
-
-       /* reject messages if tty has not yet been opened */
-       if (priv->tty_state == TTY_CLOSED) {
-               iucv_message_reject(path, msg);
-               goto unlock_return;
-       }
-
-       /* allocate tty buffer to save iucv msg only */
-       rb = alloc_tty_buffer(0, GFP_ATOMIC);
-       if (!rb) {
-               iucv_message_reject(path, msg);
-               goto unlock_return;     /* -ENOMEM */
-       }
-       rb->msg = *msg;
-
-       list_add_tail(&rb->list, &priv->tty_inqueue);
-
-       hvc_kick();     /* wake up hvc thread */
-
-unlock_return:
-       spin_unlock(&priv->lock);
-}
-
-/**
- * hvc_iucv_msg_complete() - IUCV handler to process message completion
- * @path:      Pending path (struct iucv_path)
- * @msg:       Pointer to the IUCV message
- *
- * The function is called upon completion of message delivery to remove the
- * message from the outqueue. Additional delivery information can be found
- * msg->audit: rejected messages (0x040000 (IPADRJCT)), and
- *            purged messages   (0x010000 (IPADPGNR)).
- *
- * Locking:    struct hvc_iucv_private->lock
- */
-static void hvc_iucv_msg_complete(struct iucv_path *path,
-                                 struct iucv_message *msg)
-{
-       struct hvc_iucv_private *priv = path->private;
-       struct iucv_tty_buffer  *ent, *next;
-       LIST_HEAD(list_remove);
-
-       spin_lock(&priv->lock);
-       list_for_each_entry_safe(ent, next, &priv->tty_outqueue, list)
-               if (ent->msg.id == msg->id) {
-                       list_move(&ent->list, &list_remove);
-                       break;
-               }
-       wake_up(&priv->sndbuf_waitq);
-       spin_unlock(&priv->lock);
-       destroy_tty_buffer_list(&list_remove);
-}
-
-/**
- * hvc_iucv_pm_freeze() - Freeze PM callback
- * @dev:       IUVC HVC terminal device
- *
- * Sever an established IUCV communication path and
- * trigger a hang-up of the underlying HVC terminal.
- */
-static int hvc_iucv_pm_freeze(struct device *dev)
-{
-       struct hvc_iucv_private *priv = dev_get_drvdata(dev);
-
-       local_bh_disable();
-       hvc_iucv_hangup(priv);
-       local_bh_enable();
-
-       return 0;
-}
-
-/**
- * hvc_iucv_pm_restore_thaw() - Thaw and restore PM callback
- * @dev:       IUVC HVC terminal device
- *
- * Wake up the HVC thread to trigger hang-up and respective
- * HVC back-end notifier invocations.
- */
-static int hvc_iucv_pm_restore_thaw(struct device *dev)
-{
-       hvc_kick();
-       return 0;
-}
-
-
-/* HVC operations */
-static const struct hv_ops hvc_iucv_ops = {
-       .get_chars = hvc_iucv_get_chars,
-       .put_chars = hvc_iucv_put_chars,
-       .notifier_add = hvc_iucv_notifier_add,
-       .notifier_del = hvc_iucv_notifier_del,
-       .notifier_hangup = hvc_iucv_notifier_hangup,
-};
-
-/* Suspend / resume device operations */
-static const struct dev_pm_ops hvc_iucv_pm_ops = {
-       .freeze   = hvc_iucv_pm_freeze,
-       .thaw     = hvc_iucv_pm_restore_thaw,
-       .restore  = hvc_iucv_pm_restore_thaw,
-};
-
-/* IUCV HVC device driver */
-static struct device_driver hvc_iucv_driver = {
-       .name = KMSG_COMPONENT,
-       .bus  = &iucv_bus,
-       .pm   = &hvc_iucv_pm_ops,
-};
-
-/**
- * hvc_iucv_alloc() - Allocates a new struct hvc_iucv_private instance
- * @id:                        hvc_iucv_table index
- * @is_console:                Flag if the instance is used as Linux console
- *
- * This function allocates a new hvc_iucv_private structure and stores
- * the instance in hvc_iucv_table at index @id.
- * Returns 0 on success; otherwise non-zero.
- */
-static int __init hvc_iucv_alloc(int id, unsigned int is_console)
-{
-       struct hvc_iucv_private *priv;
-       char name[9];
-       int rc;
-
-       priv = kzalloc(sizeof(struct hvc_iucv_private), GFP_KERNEL);
-       if (!priv)
-               return -ENOMEM;
-
-       spin_lock_init(&priv->lock);
-       INIT_LIST_HEAD(&priv->tty_outqueue);
-       INIT_LIST_HEAD(&priv->tty_inqueue);
-       INIT_DELAYED_WORK(&priv->sndbuf_work, hvc_iucv_sndbuf_work);
-       init_waitqueue_head(&priv->sndbuf_waitq);
-
-       priv->sndbuf = (void *) get_zeroed_page(GFP_KERNEL);
-       if (!priv->sndbuf) {
-               kfree(priv);
-               return -ENOMEM;
-       }
-
-       /* set console flag */
-       priv->is_console = is_console;
-
-       /* allocate hvc device */
-       priv->hvc = hvc_alloc(HVC_IUCV_MAGIC + id, /*             PAGE_SIZE */
-                             HVC_IUCV_MAGIC + id, &hvc_iucv_ops, 256);
-       if (IS_ERR(priv->hvc)) {
-               rc = PTR_ERR(priv->hvc);
-               goto out_error_hvc;
-       }
-
-       /* notify HVC thread instead of using polling */
-       priv->hvc->irq_requested = 1;
-
-       /* setup iucv related information */
-       snprintf(name, 9, "lnxhvc%-2d", id);
-       memcpy(priv->srv_name, name, 8);
-       ASCEBC(priv->srv_name, 8);
-
-       /* create and setup device */
-       priv->dev = kzalloc(sizeof(*priv->dev), GFP_KERNEL);
-       if (!priv->dev) {
-               rc = -ENOMEM;
-               goto out_error_dev;
-       }
-       dev_set_name(priv->dev, "hvc_iucv%d", id);
-       dev_set_drvdata(priv->dev, priv);
-       priv->dev->bus = &iucv_bus;
-       priv->dev->parent = iucv_root;
-       priv->dev->driver = &hvc_iucv_driver;
-       priv->dev->release = (void (*)(struct device *)) kfree;
-       rc = device_register(priv->dev);
-       if (rc) {
-               put_device(priv->dev);
-               goto out_error_dev;
-       }
-
-       hvc_iucv_table[id] = priv;
-       return 0;
-
-out_error_dev:
-       hvc_remove(priv->hvc);
-out_error_hvc:
-       free_page((unsigned long) priv->sndbuf);
-       kfree(priv);
-
-       return rc;
-}
-
-/**
- * hvc_iucv_destroy() - Destroy and free hvc_iucv_private instances
- */
-static void __init hvc_iucv_destroy(struct hvc_iucv_private *priv)
-{
-       hvc_remove(priv->hvc);
-       device_unregister(priv->dev);
-       free_page((unsigned long) priv->sndbuf);
-       kfree(priv);
-}
-
-/**
- * hvc_iucv_parse_filter() - Parse filter for a single z/VM user ID
- * @filter:    String containing a comma-separated list of z/VM user IDs
- */
-static const char *hvc_iucv_parse_filter(const char *filter, char *dest)
-{
-       const char *nextdelim, *residual;
-       size_t len;
-
-       nextdelim = strchr(filter, ',');
-       if (nextdelim) {
-               len = nextdelim - filter;
-               residual = nextdelim + 1;
-       } else {
-               len = strlen(filter);
-               residual = filter + len;
-       }
-
-       if (len == 0)
-               return ERR_PTR(-EINVAL);
-
-       /* check for '\n' (if called from sysfs) */
-       if (filter[len - 1] == '\n')
-               len--;
-
-       if (len > 8)
-               return ERR_PTR(-EINVAL);
-
-       /* pad with blanks and save upper case version of user ID */
-       memset(dest, ' ', 8);
-       while (len--)
-               dest[len] = toupper(filter[len]);
-       return residual;
-}
-
-/**
- * hvc_iucv_setup_filter() - Set up z/VM user ID filter
- * @filter:    String consisting of a comma-separated list of z/VM user IDs
- *
- * The function parses the @filter string and creates an array containing
- * the list of z/VM user ID filter entries.
- * Return code 0 means success, -EINVAL if the filter is syntactically
- * incorrect, -ENOMEM if there was not enough memory to allocate the
- * filter list array, or -ENOSPC if too many z/VM user IDs have been specified.
- */
-static int hvc_iucv_setup_filter(const char *val)
-{
-       const char *residual;
-       int err;
-       size_t size, count;
-       void *array, *old_filter;
-
-       count = strlen(val);
-       if (count == 0 || (count == 1 && val[0] == '\n')) {
-               size  = 0;
-               array = NULL;
-               goto out_replace_filter;        /* clear filter */
-       }
-
-       /* count user IDs in order to allocate sufficient memory */
-       size = 1;
-       residual = val;
-       while ((residual = strchr(residual, ',')) != NULL) {
-               residual++;
-               size++;
-       }
-
-       /* check if the specified list exceeds the filter limit */
-       if (size > MAX_VMID_FILTER)
-               return -ENOSPC;
-
-       array = kzalloc(size * 8, GFP_KERNEL);
-       if (!array)
-               return -ENOMEM;
-
-       count = size;
-       residual = val;
-       while (*residual && count) {
-               residual = hvc_iucv_parse_filter(residual,
-                                                array + ((size - count) * 8));
-               if (IS_ERR(residual)) {
-                       err = PTR_ERR(residual);
-                       kfree(array);
-                       goto out_err;
-               }
-               count--;
-       }
-
-out_replace_filter:
-       write_lock_bh(&hvc_iucv_filter_lock);
-       old_filter = hvc_iucv_filter;
-       hvc_iucv_filter_size = size;
-       hvc_iucv_filter = array;
-       write_unlock_bh(&hvc_iucv_filter_lock);
-       kfree(old_filter);
-
-       err = 0;
-out_err:
-       return err;
-}
-
-/**
- * param_set_vmidfilter() - Set z/VM user ID filter parameter
- * @val:       String consisting of a comma-separated list of z/VM user IDs
- * @kp:                Kernel parameter pointing to hvc_iucv_filter array
- *
- * The function sets up the z/VM user ID filter specified as comma-separated
- * list of user IDs in @val.
- * Note: If it is called early in the boot process, @val is stored and
- *      parsed later in hvc_iucv_init().
- */
-static int param_set_vmidfilter(const char *val, const struct kernel_param *kp)
-{
-       int rc;
-
-       if (!MACHINE_IS_VM || !hvc_iucv_devices)
-               return -ENODEV;
-
-       if (!val)
-               return -EINVAL;
-
-       rc = 0;
-       if (slab_is_available())
-               rc = hvc_iucv_setup_filter(val);
-       else
-               hvc_iucv_filter_string = val;   /* defer... */
-       return rc;
-}
-
-/**
- * param_get_vmidfilter() - Get z/VM user ID filter
- * @buffer:    Buffer to store z/VM user ID filter,
- *             (buffer size assumption PAGE_SIZE)
- * @kp:                Kernel parameter pointing to the hvc_iucv_filter array
- *
- * The function stores the filter as a comma-separated list of z/VM user IDs
- * in @buffer. Typically, sysfs routines call this function for attr show.
- */
-static int param_get_vmidfilter(char *buffer, const struct kernel_param *kp)
-{
-       int rc;
-       size_t index, len;
-       void *start, *end;
-
-       if (!MACHINE_IS_VM || !hvc_iucv_devices)
-               return -ENODEV;
-
-       rc = 0;
-       read_lock_bh(&hvc_iucv_filter_lock);
-       for (index = 0; index < hvc_iucv_filter_size; index++) {
-               start = hvc_iucv_filter + (8 * index);
-               end   = memchr(start, ' ', 8);
-               len   = (end) ? end - start : 8;
-               memcpy(buffer + rc, start, len);
-               rc += len;
-               buffer[rc++] = ',';
-       }
-       read_unlock_bh(&hvc_iucv_filter_lock);
-       if (rc)
-               buffer[--rc] = '\0';    /* replace last comma and update rc */
-       return rc;
-}
-
-#define param_check_vmidfilter(name, p) __param_check(name, p, void)
-
-static struct kernel_param_ops param_ops_vmidfilter = {
-       .set = param_set_vmidfilter,
-       .get = param_get_vmidfilter,
-};
-
-/**
- * hvc_iucv_init() - z/VM IUCV HVC device driver initialization
- */
-static int __init hvc_iucv_init(void)
-{
-       int rc;
-       unsigned int i;
-
-       if (!hvc_iucv_devices)
-               return -ENODEV;
-
-       if (!MACHINE_IS_VM) {
-               pr_notice("The z/VM IUCV HVC device driver cannot "
-                          "be used without z/VM\n");
-               rc = -ENODEV;
-               goto out_error;
-       }
-
-       if (hvc_iucv_devices > MAX_HVC_IUCV_LINES) {
-               pr_err("%lu is not a valid value for the hvc_iucv= "
-                       "kernel parameter\n", hvc_iucv_devices);
-               rc = -EINVAL;
-               goto out_error;
-       }
-
-       /* register IUCV HVC device driver */
-       rc = driver_register(&hvc_iucv_driver);
-       if (rc)
-               goto out_error;
-
-       /* parse hvc_iucv_allow string and create z/VM user ID filter list */
-       if (hvc_iucv_filter_string) {
-               rc = hvc_iucv_setup_filter(hvc_iucv_filter_string);
-               switch (rc) {
-               case 0:
-                       break;
-               case -ENOMEM:
-                       pr_err("Allocating memory failed with "
-                               "reason code=%d\n", 3);
-                       goto out_error;
-               case -EINVAL:
-                       pr_err("hvc_iucv_allow= does not specify a valid "
-                               "z/VM user ID list\n");
-                       goto out_error;
-               case -ENOSPC:
-                       pr_err("hvc_iucv_allow= specifies too many "
-                               "z/VM user IDs\n");
-                       goto out_error;
-               default:
-                       goto out_error;
-               }
-       }
-
-       hvc_iucv_buffer_cache = kmem_cache_create(KMSG_COMPONENT,
-                                          sizeof(struct iucv_tty_buffer),
-                                          0, 0, NULL);
-       if (!hvc_iucv_buffer_cache) {
-               pr_err("Allocating memory failed with reason code=%d\n", 1);
-               rc = -ENOMEM;
-               goto out_error;
-       }
-
-       hvc_iucv_mempool = mempool_create_slab_pool(MEMPOOL_MIN_NR,
-                                                   hvc_iucv_buffer_cache);
-       if (!hvc_iucv_mempool) {
-               pr_err("Allocating memory failed with reason code=%d\n", 2);
-               kmem_cache_destroy(hvc_iucv_buffer_cache);
-               rc = -ENOMEM;
-               goto out_error;
-       }
-
-       /* register the first terminal device as console
-        * (must be done before allocating hvc terminal devices) */
-       rc = hvc_instantiate(HVC_IUCV_MAGIC, IUCV_HVC_CON_IDX, &hvc_iucv_ops);
-       if (rc) {
-               pr_err("Registering HVC terminal device as "
-                      "Linux console failed\n");
-               goto out_error_memory;
-       }
-
-       /* allocate hvc_iucv_private structs */
-       for (i = 0; i < hvc_iucv_devices; i++) {
-               rc = hvc_iucv_alloc(i, (i == IUCV_HVC_CON_IDX) ? 1 : 0);
-               if (rc) {
-                       pr_err("Creating a new HVC terminal device "
-                               "failed with error code=%d\n", rc);
-                       goto out_error_hvc;
-               }
-       }
-
-       /* register IUCV callback handler */
-       rc = iucv_register(&hvc_iucv_handler, 0);
-       if (rc) {
-               pr_err("Registering IUCV handlers failed with error code=%d\n",
-                       rc);
-               goto out_error_hvc;
-       }
-
-       return 0;
-
-out_error_hvc:
-       for (i = 0; i < hvc_iucv_devices; i++)
-               if (hvc_iucv_table[i])
-                       hvc_iucv_destroy(hvc_iucv_table[i]);
-out_error_memory:
-       mempool_destroy(hvc_iucv_mempool);
-       kmem_cache_destroy(hvc_iucv_buffer_cache);
-out_error:
-       if (hvc_iucv_filter)
-               kfree(hvc_iucv_filter);
-       hvc_iucv_devices = 0; /* ensure that we do not provide any device */
-       return rc;
-}
-
-/**
- * hvc_iucv_config() - Parsing of hvc_iucv=  kernel command line parameter
- * @val:       Parameter value (numeric)
- */
-static int __init hvc_iucv_config(char *val)
-{
-        return strict_strtoul(val, 10, &hvc_iucv_devices);
-}
-
-
-device_initcall(hvc_iucv_init);
-__setup("hvc_iucv=", hvc_iucv_config);
-core_param(hvc_iucv_allow, hvc_iucv_filter, vmidfilter, 0640);
diff --git a/drivers/char/hvc_rtas.c b/drivers/char/hvc_rtas.c
deleted file mode 100644 (file)
index 61c4a61..0000000
+++ /dev/null
@@ -1,133 +0,0 @@
-/*
- * IBM RTAS driver interface to hvc_console.c
- *
- * (C) Copyright IBM Corporation 2001-2005
- * (C) Copyright Red Hat, Inc. 2005
- *
- * Author(s): Maximino Augilar <IBM STI Design Center>
- *         : Ryan S. Arnold <rsa@us.ibm.com>
- *         : Utz Bacher <utz.bacher@de.ibm.com>
- *         : David Woodhouse <dwmw2@infradead.org>
- *
- *    inspired by drivers/char/hvc_console.c
- *    written by Anton Blanchard and Paul Mackerras
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
- */
-
-#include <linux/console.h>
-#include <linux/delay.h>
-#include <linux/err.h>
-#include <linux/init.h>
-#include <linux/moduleparam.h>
-#include <linux/types.h>
-
-#include <asm/irq.h>
-#include <asm/rtas.h>
-#include "hvc_console.h"
-
-#define hvc_rtas_cookie 0x67781e15
-struct hvc_struct *hvc_rtas_dev;
-
-static int rtascons_put_char_token = RTAS_UNKNOWN_SERVICE;
-static int rtascons_get_char_token = RTAS_UNKNOWN_SERVICE;
-
-static inline int hvc_rtas_write_console(uint32_t vtermno, const char *buf,
-               int count)
-{
-       int i;
-
-       for (i = 0; i < count; i++) {
-               if (rtas_call(rtascons_put_char_token, 1, 1, NULL, buf[i]))
-                       break;
-       }
-
-       return i;
-}
-
-static int hvc_rtas_read_console(uint32_t vtermno, char *buf, int count)
-{
-       int i, c;
-
-       for (i = 0; i < count; i++) {
-               if (rtas_call(rtascons_get_char_token, 0, 2, &c))
-                       break;
-
-               buf[i] = c;
-       }
-
-       return i;
-}
-
-static const struct hv_ops hvc_rtas_get_put_ops = {
-       .get_chars = hvc_rtas_read_console,
-       .put_chars = hvc_rtas_write_console,
-};
-
-static int __init hvc_rtas_init(void)
-{
-       struct hvc_struct *hp;
-
-       if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE)
-               rtascons_put_char_token = rtas_token("put-term-char");
-       if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE)
-               return -EIO;
-
-       if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE)
-               rtascons_get_char_token = rtas_token("get-term-char");
-       if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE)
-               return -EIO;
-
-       BUG_ON(hvc_rtas_dev);
-
-       /* Allocate an hvc_struct for the console device we instantiated
-        * earlier.  Save off hp so that we can return it on exit */
-       hp = hvc_alloc(hvc_rtas_cookie, NO_IRQ, &hvc_rtas_get_put_ops, 16);
-       if (IS_ERR(hp))
-               return PTR_ERR(hp);
-
-       hvc_rtas_dev = hp;
-
-       return 0;
-}
-module_init(hvc_rtas_init);
-
-/* This will tear down the tty portion of the driver */
-static void __exit hvc_rtas_exit(void)
-{
-       /* Really the fun isn't over until the worker thread breaks down and
-        * the tty cleans up */
-       if (hvc_rtas_dev)
-               hvc_remove(hvc_rtas_dev);
-}
-module_exit(hvc_rtas_exit);
-
-/* This will happen prior to module init.  There is no tty at this time? */
-static int __init hvc_rtas_console_init(void)
-{
-       rtascons_put_char_token = rtas_token("put-term-char");
-       if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE)
-               return -EIO;
-
-       rtascons_get_char_token = rtas_token("get-term-char");
-       if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE)
-               return -EIO;
-
-       hvc_instantiate(hvc_rtas_cookie, 0, &hvc_rtas_get_put_ops);
-       add_preferred_console("hvc", 0, NULL);
-
-       return 0;
-}
-console_initcall(hvc_rtas_console_init);
diff --git a/drivers/char/hvc_tile.c b/drivers/char/hvc_tile.c
deleted file mode 100644 (file)
index 7a84a05..0000000
+++ /dev/null
@@ -1,68 +0,0 @@
-/*
- * Copyright 2010 Tilera Corporation. All Rights Reserved.
- *
- *   This program is free software; you can redistribute it and/or
- *   modify it under the terms of the GNU General Public License
- *   as published by the Free Software Foundation, version 2.
- *
- *   This program is distributed in the hope that it will be useful, but
- *   WITHOUT ANY WARRANTY; without even the implied warranty of
- *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
- *   NON INFRINGEMENT.  See the GNU General Public License for
- *   more details.
- *
- * Tilera TILE Processor hypervisor console
- */
-
-#include <linux/console.h>
-#include <linux/delay.h>
-#include <linux/err.h>
-#include <linux/init.h>
-#include <linux/moduleparam.h>
-#include <linux/types.h>
-
-#include <hv/hypervisor.h>
-
-#include "hvc_console.h"
-
-static int hvc_tile_put_chars(uint32_t vt, const char *buf, int count)
-{
-       return hv_console_write((HV_VirtAddr)buf, count);
-}
-
-static int hvc_tile_get_chars(uint32_t vt, char *buf, int count)
-{
-       int i, c;
-
-       for (i = 0; i < count; ++i) {
-               c = hv_console_read_if_ready();
-               if (c < 0)
-                       break;
-               buf[i] = c;
-       }
-
-       return i;
-}
-
-static const struct hv_ops hvc_tile_get_put_ops = {
-       .get_chars = hvc_tile_get_chars,
-       .put_chars = hvc_tile_put_chars,
-};
-
-static int __init hvc_tile_console_init(void)
-{
-       extern void disable_early_printk(void);
-       hvc_instantiate(0, 0, &hvc_tile_get_put_ops);
-       add_preferred_console("hvc", 0, NULL);
-       disable_early_printk();
-       return 0;
-}
-console_initcall(hvc_tile_console_init);
-
-static int __init hvc_tile_init(void)
-{
-       struct hvc_struct *s;
-       s = hvc_alloc(0, 0, &hvc_tile_get_put_ops, 128);
-       return IS_ERR(s) ? PTR_ERR(s) : 0;
-}
-device_initcall(hvc_tile_init);
diff --git a/drivers/char/hvc_udbg.c b/drivers/char/hvc_udbg.c
deleted file mode 100644 (file)
index b0957e6..0000000
+++ /dev/null
@@ -1,96 +0,0 @@
-/*
- * udbg interface to hvc_console.c
- *
- * (C) Copyright David Gibson, IBM Corporation 2008.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
- */
-
-#include <linux/console.h>
-#include <linux/delay.h>
-#include <linux/err.h>
-#include <linux/init.h>
-#include <linux/moduleparam.h>
-#include <linux/types.h>
-#include <linux/irq.h>
-
-#include <asm/udbg.h>
-
-#include "hvc_console.h"
-
-struct hvc_struct *hvc_udbg_dev;
-
-static int hvc_udbg_put(uint32_t vtermno, const char *buf, int count)
-{
-       int i;
-
-       for (i = 0; i < count; i++)
-               udbg_putc(buf[i]);
-
-       return i;
-}
-
-static int hvc_udbg_get(uint32_t vtermno, char *buf, int count)
-{
-       int i, c;
-
-       if (!udbg_getc_poll)
-               return 0;
-
-       for (i = 0; i < count; i++) {
-               if ((c = udbg_getc_poll()) == -1)
-                       break;
-               buf[i] = c;
-       }
-
-       return i;
-}
-
-static const struct hv_ops hvc_udbg_ops = {
-       .get_chars = hvc_udbg_get,
-       .put_chars = hvc_udbg_put,
-};
-
-static int __init hvc_udbg_init(void)
-{
-       struct hvc_struct *hp;
-
-       BUG_ON(hvc_udbg_dev);
-
-       hp = hvc_alloc(0, NO_IRQ, &hvc_udbg_ops, 16);
-       if (IS_ERR(hp))
-               return PTR_ERR(hp);
-
-       hvc_udbg_dev = hp;
-
-       return 0;
-}
-module_init(hvc_udbg_init);
-
-static void __exit hvc_udbg_exit(void)
-{
-       if (hvc_udbg_dev)
-               hvc_remove(hvc_udbg_dev);
-}
-module_exit(hvc_udbg_exit);
-
-static int __init hvc_udbg_console_init(void)
-{
-       hvc_instantiate(0, 0, &hvc_udbg_ops);
-       add_preferred_console("hvc", 0, NULL);
-
-       return 0;
-}
-console_initcall(hvc_udbg_console_init);
diff --git a/drivers/char/hvc_vio.c b/drivers/char/hvc_vio.c
deleted file mode 100644 (file)
index 5e2f52b..0000000
+++ /dev/null
@@ -1,173 +0,0 @@
-/*
- * vio driver interface to hvc_console.c
- *
- * This code was moved here to allow the remaing code to be reused as a
- * generic polling mode with semi-reliable transport driver core to the
- * console and tty subsystems.
- *
- *
- * Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM
- * Copyright (C) 2001 Paul Mackerras <paulus@au.ibm.com>, IBM
- * Copyright (C) 2004 Benjamin Herrenschmidt <benh@kernel.crashing.org>, IBM Corp.
- * Copyright (C) 2004 IBM Corporation
- *
- * Additional Author(s):
- *  Ryan S. Arnold <rsa@us.ibm.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
- */
-
-#include <linux/types.h>
-#include <linux/init.h>
-
-#include <asm/hvconsole.h>
-#include <asm/vio.h>
-#include <asm/prom.h>
-#include <asm/firmware.h>
-
-#include "hvc_console.h"
-
-static const char hvc_driver_name[] = "hvc_console";
-
-static struct vio_device_id hvc_driver_table[] __devinitdata = {
-       {"serial", "hvterm1"},
-       { "", "" }
-};
-MODULE_DEVICE_TABLE(vio, hvc_driver_table);
-
-static int filtered_get_chars(uint32_t vtermno, char *buf, int count)
-{
-       unsigned long got;
-       int i;
-
-       /*
-        * Vio firmware will read up to SIZE_VIO_GET_CHARS at its own discretion
-        * so we play safe and avoid the situation where got > count which could
-        * overload the flip buffer.
-        */
-       if (count < SIZE_VIO_GET_CHARS)
-               return -EAGAIN;
-
-       got = hvc_get_chars(vtermno, buf, count);
-
-       /*
-        * Work around a HV bug where it gives us a null
-        * after every \r.  -- paulus
-        */
-       for (i = 1; i < got; ++i) {
-               if (buf[i] == 0 && buf[i-1] == '\r') {
-                       --got;
-                       if (i < got)
-                               memmove(&buf[i], &buf[i+1],
-                                       got - i);
-               }
-       }
-       return got;
-}
-
-static const struct hv_ops hvc_get_put_ops = {
-       .get_chars = filtered_get_chars,
-       .put_chars = hvc_put_chars,
-       .notifier_add = notifier_add_irq,
-       .notifier_del = notifier_del_irq,
-       .notifier_hangup = notifier_hangup_irq,
-};
-
-static int __devinit hvc_vio_probe(struct vio_dev *vdev,
-                               const struct vio_device_id *id)
-{
-       struct hvc_struct *hp;
-
-       /* probed with invalid parameters. */
-       if (!vdev || !id)
-               return -EPERM;
-
-       hp = hvc_alloc(vdev->unit_address, vdev->irq, &hvc_get_put_ops,
-                       MAX_VIO_PUT_CHARS);
-       if (IS_ERR(hp))
-               return PTR_ERR(hp);
-       dev_set_drvdata(&vdev->dev, hp);
-
-       return 0;
-}
-
-static int __devexit hvc_vio_remove(struct vio_dev *vdev)
-{
-       struct hvc_struct *hp = dev_get_drvdata(&vdev->dev);
-
-       return hvc_remove(hp);
-}
-
-static struct vio_driver hvc_vio_driver = {
-       .id_table       = hvc_driver_table,
-       .probe          = hvc_vio_probe,
-       .remove         = __devexit_p(hvc_vio_remove),
-       .driver         = {
-               .name   = hvc_driver_name,
-               .owner  = THIS_MODULE,
-       }
-};
-
-static int __init hvc_vio_init(void)
-{
-       int rc;
-
-       if (firmware_has_feature(FW_FEATURE_ISERIES))
-               return -EIO;
-
-       /* Register as a vio device to receive callbacks */
-       rc = vio_register_driver(&hvc_vio_driver);
-
-       return rc;
-}
-module_init(hvc_vio_init); /* after drivers/char/hvc_console.c */
-
-static void __exit hvc_vio_exit(void)
-{
-       vio_unregister_driver(&hvc_vio_driver);
-}
-module_exit(hvc_vio_exit);
-
-/* the device tree order defines our numbering */
-static int hvc_find_vtys(void)
-{
-       struct device_node *vty;
-       int num_found = 0;
-
-       for (vty = of_find_node_by_name(NULL, "vty"); vty != NULL;
-                       vty = of_find_node_by_name(vty, "vty")) {
-               const uint32_t *vtermno;
-
-               /* We have statically defined space for only a certain number
-                * of console adapters.
-                */
-               if (num_found >= MAX_NR_HVC_CONSOLES) {
-                       of_node_put(vty);
-                       break;
-               }
-
-               vtermno = of_get_property(vty, "reg", NULL);
-               if (!vtermno)
-                       continue;
-
-               if (of_device_is_compatible(vty, "hvterm1")) {
-                       hvc_instantiate(*vtermno, num_found, &hvc_get_put_ops);
-                       ++num_found;
-               }
-       }
-
-       return num_found;
-}
-console_initcall(hvc_find_vtys);
diff --git a/drivers/char/hvc_xen.c b/drivers/char/hvc_xen.c
deleted file mode 100644 (file)
index 3740e32..0000000
+++ /dev/null
@@ -1,271 +0,0 @@
-/*
- * xen console driver interface to hvc_console.c
- *
- * (c) 2007 Gerd Hoffmann <kraxel@suse.de>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
- */
-
-#include <linux/console.h>
-#include <linux/delay.h>
-#include <linux/err.h>
-#include <linux/init.h>
-#include <linux/types.h>
-
-#include <asm/xen/hypervisor.h>
-
-#include <xen/xen.h>
-#include <xen/page.h>
-#include <xen/events.h>
-#include <xen/interface/io/console.h>
-#include <xen/hvc-console.h>
-
-#include "hvc_console.h"
-
-#define HVC_COOKIE   0x58656e /* "Xen" in hex */
-
-static struct hvc_struct *hvc;
-static int xencons_irq;
-
-/* ------------------------------------------------------------------ */
-
-static unsigned long console_pfn = ~0ul;
-
-static inline struct xencons_interface *xencons_interface(void)
-{
-       if (console_pfn == ~0ul)
-               return mfn_to_virt(xen_start_info->console.domU.mfn);
-       else
-               return __va(console_pfn << PAGE_SHIFT);
-}
-
-static inline void notify_daemon(void)
-{
-       /* Use evtchn: this is called early, before irq is set up. */
-       notify_remote_via_evtchn(xen_start_info->console.domU.evtchn);
-}
-
-static int __write_console(const char *data, int len)
-{
-       struct xencons_interface *intf = xencons_interface();
-       XENCONS_RING_IDX cons, prod;
-       int sent = 0;
-
-       cons = intf->out_cons;
-       prod = intf->out_prod;
-       mb();                   /* update queue values before going on */
-       BUG_ON((prod - cons) > sizeof(intf->out));
-
-       while ((sent < len) && ((prod - cons) < sizeof(intf->out)))
-               intf->out[MASK_XENCONS_IDX(prod++, intf->out)] = data[sent++];
-
-       wmb();                  /* write ring before updating pointer */
-       intf->out_prod = prod;
-
-       if (sent)
-               notify_daemon();
-       return sent;
-}
-
-static int domU_write_console(uint32_t vtermno, const char *data, int len)
-{
-       int ret = len;
-
-       /*
-        * Make sure the whole buffer is emitted, polling if
-        * necessary.  We don't ever want to rely on the hvc daemon
-        * because the most interesting console output is when the
-        * kernel is crippled.
-        */
-       while (len) {
-               int sent = __write_console(data, len);
-               
-               data += sent;
-               len -= sent;
-
-               if (unlikely(len))
-                       HYPERVISOR_sched_op(SCHEDOP_yield, NULL);
-       }
-
-       return ret;
-}
-
-static int domU_read_console(uint32_t vtermno, char *buf, int len)
-{
-       struct xencons_interface *intf = xencons_interface();
-       XENCONS_RING_IDX cons, prod;
-       int recv = 0;
-
-       cons = intf->in_cons;
-       prod = intf->in_prod;
-       mb();                   /* get pointers before reading ring */
-       BUG_ON((prod - cons) > sizeof(intf->in));
-
-       while (cons != prod && recv < len)
-               buf[recv++] = intf->in[MASK_XENCONS_IDX(cons++, intf->in)];
-
-       mb();                   /* read ring before consuming */
-       intf->in_cons = cons;
-
-       notify_daemon();
-       return recv;
-}
-
-static struct hv_ops domU_hvc_ops = {
-       .get_chars = domU_read_console,
-       .put_chars = domU_write_console,
-       .notifier_add = notifier_add_irq,
-       .notifier_del = notifier_del_irq,
-       .notifier_hangup = notifier_hangup_irq,
-};
-
-static int dom0_read_console(uint32_t vtermno, char *buf, int len)
-{
-       return HYPERVISOR_console_io(CONSOLEIO_read, len, buf);
-}
-
-/*
- * Either for a dom0 to write to the system console, or a domU with a
- * debug version of Xen
- */
-static int dom0_write_console(uint32_t vtermno, const char *str, int len)
-{
-       int rc = HYPERVISOR_console_io(CONSOLEIO_write, len, (char *)str);
-       if (rc < 0)
-               return 0;
-
-       return len;
-}
-
-static struct hv_ops dom0_hvc_ops = {
-       .get_chars = dom0_read_console,
-       .put_chars = dom0_write_console,
-       .notifier_add = notifier_add_irq,
-       .notifier_del = notifier_del_irq,
-       .notifier_hangup = notifier_hangup_irq,
-};
-
-static int __init xen_hvc_init(void)
-{
-       struct hvc_struct *hp;
-       struct hv_ops *ops;
-
-       if (!xen_pv_domain())
-               return -ENODEV;
-
-       if (xen_initial_domain()) {
-               ops = &dom0_hvc_ops;
-               xencons_irq = bind_virq_to_irq(VIRQ_CONSOLE, 0);
-       } else {
-               if (!xen_start_info->console.domU.evtchn)
-                       return -ENODEV;
-
-               ops = &domU_hvc_ops;
-               xencons_irq = bind_evtchn_to_irq(xen_start_info->console.domU.evtchn);
-       }
-       if (xencons_irq < 0)
-               xencons_irq = 0; /* NO_IRQ */
-
-       hp = hvc_alloc(HVC_COOKIE, xencons_irq, ops, 256);
-       if (IS_ERR(hp))
-               return PTR_ERR(hp);
-
-       hvc = hp;
-
-       console_pfn = mfn_to_pfn(xen_start_info->console.domU.mfn);
-
-       return 0;
-}
-
-void xen_console_resume(void)
-{
-       if (xencons_irq)
-               rebind_evtchn_irq(xen_start_info->console.domU.evtchn, xencons_irq);
-}
-
-static void __exit xen_hvc_fini(void)
-{
-       if (hvc)
-               hvc_remove(hvc);
-}
-
-static int xen_cons_init(void)
-{
-       struct hv_ops *ops;
-
-       if (!xen_pv_domain())
-               return 0;
-
-       if (xen_initial_domain())
-               ops = &dom0_hvc_ops;
-       else
-               ops = &domU_hvc_ops;
-
-       hvc_instantiate(HVC_COOKIE, 0, ops);
-       return 0;
-}
-
-module_init(xen_hvc_init);
-module_exit(xen_hvc_fini);
-console_initcall(xen_cons_init);
-
-#ifdef CONFIG_EARLY_PRINTK
-static void xenboot_write_console(struct console *console, const char *string,
-                                 unsigned len)
-{
-       unsigned int linelen, off = 0;
-       const char *pos;
-
-       dom0_write_console(0, string, len);
-
-       if (xen_initial_domain())
-               return;
-
-       domU_write_console(0, "(early) ", 8);
-       while (off < len && NULL != (pos = strchr(string+off, '\n'))) {
-               linelen = pos-string+off;
-               if (off + linelen > len)
-                       break;
-               domU_write_console(0, string+off, linelen);
-               domU_write_console(0, "\r\n", 2);
-               off += linelen + 1;
-       }
-       if (off < len)
-               domU_write_console(0, string+off, len-off);
-}
-
-struct console xenboot_console = {
-       .name           = "xenboot",
-       .write          = xenboot_write_console,
-       .flags          = CON_PRINTBUFFER | CON_BOOT | CON_ANYTIME,
-};
-#endif /* CONFIG_EARLY_PRINTK */
-
-void xen_raw_console_write(const char *str)
-{
-       dom0_write_console(0, str, strlen(str));
-}
-
-void xen_raw_printk(const char *fmt, ...)
-{
-       static char buf[512];
-       va_list ap;
-
-       va_start(ap, fmt);
-       vsnprintf(buf, sizeof(buf), fmt, ap);
-       va_end(ap);
-
-       xen_raw_console_write(buf);
-}
diff --git a/drivers/char/hvcs.c b/drivers/char/hvcs.c
deleted file mode 100644 (file)
index bedc6c1..0000000
+++ /dev/null
@@ -1,1604 +0,0 @@
-/*
- * IBM eServer Hypervisor Virtual Console Server Device Driver
- * Copyright (C) 2003, 2004 IBM Corp.
- *  Ryan S. Arnold (rsa@us.ibm.com)
- *
- *  This program is free software; you can redistribute it and/or modify
- *  it under the terms of the GNU General Public License as published by
- *  the Free Software Foundation; either version 2 of the License, or
- *  (at your option) any later version.
- *
- *  This program is distributed in the hope that it will be useful,
- *  but WITHOUT ANY WARRANTY; without even the implied warranty of
- *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- *  GNU General Public License for more details.
- *
- *  You should have received a copy of the GNU General Public License
- *  along with this program; if not, write to the Free Software
- *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
- *
- * Author(s) :  Ryan S. Arnold <rsa@us.ibm.com>
- *
- * This is the device driver for the IBM Hypervisor Virtual Console Server,
- * "hvcs".  The IBM hvcs provides a tty driver interface to allow Linux
- * user space applications access to the system consoles of logically
- * partitioned operating systems, e.g. Linux, running on the same partitioned
- * Power5 ppc64 system.  Physical hardware consoles per partition are not
- * practical on this hardware so system consoles are accessed by this driver
- * using inter-partition firmware interfaces to virtual terminal devices.
- *
- * A vty is known to the HMC as a "virtual serial server adapter".  It is a
- * virtual terminal device that is created by firmware upon partition creation
- * to act as a partitioned OS's console device.
- *
- * Firmware dynamically (via hotplug) exposes vty-servers to a running ppc64
- * Linux system upon their creation by the HMC or their exposure during boot.
- * The non-user interactive backend of this driver is implemented as a vio
- * device driver so that it can receive notification of vty-server lifetimes
- * after it registers with the vio bus to handle vty-server probe and remove
- * callbacks.
- *
- * Many vty-servers can be configured to connect to one vty, but a vty can
- * only be actively connected to by a single vty-server, in any manner, at one
- * time.  If the HMC is currently hosting the console for a target Linux
- * partition; attempts to open the tty device to the partition's console using
- * the hvcs on any partition will return -EBUSY with every open attempt until
- * the HMC frees the connection between its vty-server and the desired
- * partition's vty device.  Conversely, a vty-server may only be connected to
- * a single vty at one time even though it may have several configured vty
- * partner possibilities.
- *
- * Firmware does not provide notification of vty partner changes to this
- * driver.  This means that an HMC Super Admin may add or remove partner vtys
- * from a vty-server's partner list but the changes will not be signaled to
- * the vty-server.  Firmware only notifies the driver when a vty-server is
- * added or removed from the system.  To compensate for this deficiency, this
- * driver implements a sysfs update attribute which provides a method for
- * rescanning partner information upon a user's request.
- *
- * Each vty-server, prior to being exposed to this driver is reference counted
- * using the 2.6 Linux kernel kref construct.
- *
- * For direction on installation and usage of this driver please reference
- * Documentation/powerpc/hvcs.txt.
- */
-
-#include <linux/device.h>
-#include <linux/init.h>
-#include <linux/interrupt.h>
-#include <linux/kernel.h>
-#include <linux/kref.h>
-#include <linux/kthread.h>
-#include <linux/list.h>
-#include <linux/major.h>
-#include <linux/module.h>
-#include <linux/moduleparam.h>
-#include <linux/sched.h>
-#include <linux/slab.h>
-#include <linux/spinlock.h>
-#include <linux/stat.h>
-#include <linux/tty.h>
-#include <linux/tty_flip.h>
-#include <asm/hvconsole.h>
-#include <asm/hvcserver.h>
-#include <asm/uaccess.h>
-#include <asm/vio.h>
-
-/*
- * 1.3.0 -> 1.3.1 In hvcs_open memset(..,0x00,..) instead of memset(..,0x3F,00).
- * Removed braces around single statements following conditionals.  Removed '=
- * 0' after static int declarations since these default to zero.  Removed
- * list_for_each_safe() and replaced with list_for_each_entry() in
- * hvcs_get_by_index().  The 'safe' version is un-needed now that the driver is
- * using spinlocks.  Changed spin_lock_irqsave() to spin_lock() when locking
- * hvcs_structs_lock and hvcs_pi_lock since these are not touched in an int
- * handler.  Initialized hvcs_structs_lock and hvcs_pi_lock to
- * SPIN_LOCK_UNLOCKED at declaration time rather than in hvcs_module_init().
- * Added spin_lock around list_del() in destroy_hvcs_struct() to protect the
- * list traversals from a deletion.  Removed '= NULL' from pointer declaration
- * statements since they are initialized NULL by default.  Removed wmb()
- * instances from hvcs_try_write().  They probably aren't needed with locking in
- * place.  Added check and cleanup for hvcs_pi_buff = kmalloc() in
- * hvcs_module_init().  Exposed hvcs_struct.index via a sysfs attribute so that
- * the coupling between /dev/hvcs* and a vty-server can be automatically
- * determined.  Moved kobject_put() in hvcs_open outside of the
- * spin_unlock_irqrestore().
- *
- * 1.3.1 -> 1.3.2 Changed method for determining hvcs_struct->index and had it
- * align with how the tty layer always assigns the lowest index available.  This
- * change resulted in a list of ints that denotes which indexes are available.
- * Device additions and removals use the new hvcs_get_index() and
- * hvcs_return_index() helper functions.  The list is created with
- * hvsc_alloc_index_list() and it is destroyed with hvcs_free_index_list().
- * Without these fixes hotplug vty-server adapter support goes crazy with this
- * driver if the user removes a vty-server adapter.  Moved free_irq() outside of
- * the hvcs_final_close() function in order to get it out of the spinlock.
- * Rearranged hvcs_close().  Cleaned up some printks and did some housekeeping
- * on the changelog.  Removed local CLC_LENGTH and used HVCS_CLC_LENGTH from
- * arch/powerepc/include/asm/hvcserver.h
- *
- * 1.3.2 -> 1.3.3 Replaced yield() in hvcs_close() with tty_wait_until_sent() to
- * prevent possible lockup with realtime scheduling as similarily pointed out by
- * akpm in hvc_console.  Changed resulted in the removal of hvcs_final_close()
- * to reorder cleanup operations and prevent discarding of pending data during
- * an hvcs_close().  Removed spinlock protection of hvcs_struct data members in
- * hvcs_write_room() and hvcs_chars_in_buffer() because they aren't needed.
- */
-
-#define HVCS_DRIVER_VERSION "1.3.3"
-
-MODULE_AUTHOR("Ryan S. Arnold <rsa@us.ibm.com>");
-MODULE_DESCRIPTION("IBM hvcs (Hypervisor Virtual Console Server) Driver");
-MODULE_LICENSE("GPL");
-MODULE_VERSION(HVCS_DRIVER_VERSION);
-
-/*
- * Wait this long per iteration while trying to push buffered data to the
- * hypervisor before allowing the tty to complete a close operation.
- */
-#define HVCS_CLOSE_WAIT (HZ/100) /* 1/10 of a second */
-
-/*
- * Since the Linux TTY code does not currently (2-04-2004) support dynamic
- * addition of tty derived devices and we shouldn't allocate thousands of
- * tty_device pointers when the number of vty-server & vty partner connections
- * will most often be much lower than this, we'll arbitrarily allocate
- * HVCS_DEFAULT_SERVER_ADAPTERS tty_structs and cdev's by default when we
- * register the tty_driver. This can be overridden using an insmod parameter.
- */
-#define HVCS_DEFAULT_SERVER_ADAPTERS   64
-
-/*
- * The user can't insmod with more than HVCS_MAX_SERVER_ADAPTERS hvcs device
- * nodes as a sanity check.  Theoretically there can be over 1 Billion
- * vty-server & vty partner connections.
- */
-#define HVCS_MAX_SERVER_ADAPTERS       1024
-
-/*
- * We let Linux assign us a major number and we start the minors at zero.  There
- * is no intuitive mapping between minor number and the target vty-server
- * adapter except that each new vty-server adapter is always assigned to the
- * smallest minor number available.
- */
-#define HVCS_MINOR_START       0
-
-/*
- * The hcall interface involves putting 8 chars into each of two registers.
- * We load up those 2 registers (in arch/powerpc/platforms/pseries/hvconsole.c)
- * by casting char[16] to long[2].  It would work without __ALIGNED__, but a 
- * little (tiny) bit slower because an unaligned load is slower than aligned 
- * load.
- */
-#define __ALIGNED__    __attribute__((__aligned__(8)))
-
-/*
- * How much data can firmware send with each hvc_put_chars()?  Maybe this
- * should be moved into an architecture specific area.
- */
-#define HVCS_BUFF_LEN  16
-
-/*
- * This is the maximum amount of data we'll let the user send us (hvcs_write) at
- * once in a chunk as a sanity check.
- */
-#define HVCS_MAX_FROM_USER     4096
-
-/*
- * Be careful when adding flags to this line discipline.  Don't add anything
- * that will cause echoing or we'll go into recursive loop echoing chars back
- * and forth with the console drivers.
- */
-static struct ktermios hvcs_tty_termios = {
-       .c_iflag = IGNBRK | IGNPAR,
-       .c_oflag = OPOST,
-       .c_cflag = B38400 | CS8 | CREAD | HUPCL,
-       .c_cc = INIT_C_CC,
-       .c_ispeed = 38400,
-       .c_ospeed = 38400
-};
-
-/*
- * This value is used to take the place of a command line parameter when the
- * module is inserted.  It starts as -1 and stays as such if the user doesn't
- * specify a module insmod parameter.  If they DO specify one then it is set to
- * the value of the integer passed in.
- */
-static int hvcs_parm_num_devs = -1;
-module_param(hvcs_parm_num_devs, int, 0);
-
-static const char hvcs_driver_name[] = "hvcs";
-static const char hvcs_device_node[] = "hvcs";
-static const char hvcs_driver_string[]
-       = "IBM hvcs (Hypervisor Virtual Console Server) Driver";
-
-/* Status of partner info rescan triggered via sysfs. */
-static int hvcs_rescan_status;
-
-static struct tty_driver *hvcs_tty_driver;
-
-/*
- * In order to be somewhat sane this driver always associates the hvcs_struct
- * index element with the numerically equal tty->index.  This means that a
- * hotplugged vty-server adapter will always map to the lowest index valued
- * device node.  If vty-servers were hotplug removed from the system and then
- * new ones added the new vty-server may have the largest slot number of all
- * the vty-server adapters in the partition but it may have the lowest dev node
- * index of all the adapters due to the hole left by the hotplug removed
- * adapter.  There are a set of functions provided to get the lowest index for
- * a new device as well as return the index to the list.  This list is allocated
- * with a number of elements equal to the number of device nodes requested when
- * the module was inserted.
- */
-static int *hvcs_index_list;
-
-/*
- * How large is the list?  This is kept for traversal since the list is
- * dynamically created.
- */
-static int hvcs_index_count;
-
-/*
- * Used by the khvcsd to pick up I/O operations when the kernel_thread is
- * already awake but potentially shifted to TASK_INTERRUPTIBLE state.
- */
-static int hvcs_kicked;
-
-/*
- * Use by the kthread construct for task operations like waking the sleeping
- * thread and stopping the kthread.
- */
-static struct task_struct *hvcs_task;
-
-/*
- * We allocate this for the use of all of the hvcs_structs when they fetch
- * partner info.
- */
-static unsigned long *hvcs_pi_buff;
-
-/* Only allow one hvcs_struct to use the hvcs_pi_buff at a time. */
-static DEFINE_SPINLOCK(hvcs_pi_lock);
-
-/* One vty-server per hvcs_struct */
-struct hvcs_struct {
-       spinlock_t lock;
-
-       /*
-        * This index identifies this hvcs device as the complement to a
-        * specific tty index.
-        */
-       unsigned int index;
-
-       struct tty_struct *tty;
-       int open_count;
-
-       /*
-        * Used to tell the driver kernel_thread what operations need to take
-        * place upon this hvcs_struct instance.
-        */
-       int todo_mask;
-
-       /*
-        * This buffer is required so that when hvcs_write_room() reports that
-        * it can send HVCS_BUFF_LEN characters that it will buffer the full
-        * HVCS_BUFF_LEN characters if need be.  This is essential for opost
-        * writes since they do not do high level buffering and expect to be
-        * able to send what the driver commits to sending buffering
-        * [e.g. tab to space conversions in n_tty.c opost()].
-        */
-       char buffer[HVCS_BUFF_LEN];
-       int chars_in_buffer;
-
-       /*
-        * Any variable below the kref is valid before a tty is connected and
-        * stays valid after the tty is disconnected.  These shouldn't be
-        * whacked until the koject refcount reaches zero though some entries
-        * may be changed via sysfs initiatives.
-        */
-       struct kref kref; /* ref count & hvcs_struct lifetime */
-       int connected; /* is the vty-server currently connected to a vty? */
-       uint32_t p_unit_address; /* partner unit address */
-       uint32_t p_partition_ID; /* partner partition ID */
-       char p_location_code[HVCS_CLC_LENGTH + 1]; /* CLC + Null Term */
-       struct list_head next; /* list management */
-       struct vio_dev *vdev;
-};
-
-/* Required to back map a kref to its containing object */
-#define from_kref(k) container_of(k, struct hvcs_struct, kref)
-
-static LIST_HEAD(hvcs_structs);
-static DEFINE_SPINLOCK(hvcs_structs_lock);
-
-static void hvcs_unthrottle(struct tty_struct *tty);
-static void hvcs_throttle(struct tty_struct *tty);
-static irqreturn_t hvcs_handle_interrupt(int irq, void *dev_instance);
-
-static int hvcs_write(struct tty_struct *tty,
-               const unsigned char *buf, int count);
-static int hvcs_write_room(struct tty_struct *tty);
-static int hvcs_chars_in_buffer(struct tty_struct *tty);
-
-static int hvcs_has_pi(struct hvcs_struct *hvcsd);
-static void hvcs_set_pi(struct hvcs_partner_info *pi,
-               struct hvcs_struct *hvcsd);
-static int hvcs_get_pi(struct hvcs_struct *hvcsd);
-static int hvcs_rescan_devices_list(void);
-
-static int hvcs_partner_connect(struct hvcs_struct *hvcsd);
-static void hvcs_partner_free(struct hvcs_struct *hvcsd);
-
-static int hvcs_enable_device(struct hvcs_struct *hvcsd,
-               uint32_t unit_address, unsigned int irq, struct vio_dev *dev);
-
-static int hvcs_open(struct tty_struct *tty, struct file *filp);
-static void hvcs_close(struct tty_struct *tty, struct file *filp);
-static void hvcs_hangup(struct tty_struct * tty);
-
-static int __devinit hvcs_probe(struct vio_dev *dev,
-               const struct vio_device_id *id);
-static int __devexit hvcs_remove(struct vio_dev *dev);
-static int __init hvcs_module_init(void);
-static void __exit hvcs_module_exit(void);
-
-#define HVCS_SCHED_READ        0x00000001
-#define HVCS_QUICK_READ        0x00000002
-#define HVCS_TRY_WRITE 0x00000004
-#define HVCS_READ_MASK (HVCS_SCHED_READ | HVCS_QUICK_READ)
-
-static inline struct hvcs_struct *from_vio_dev(struct vio_dev *viod)
-{
-       return dev_get_drvdata(&viod->dev);
-}
-/* The sysfs interface for the driver and devices */
-
-static ssize_t hvcs_partner_vtys_show(struct device *dev, struct device_attribute *attr, char *buf)
-{
-       struct vio_dev *viod = to_vio_dev(dev);
-       struct hvcs_struct *hvcsd = from_vio_dev(viod);
-       unsigned long flags;
-       int retval;
-
-       spin_lock_irqsave(&hvcsd->lock, flags);
-       retval = sprintf(buf, "%X\n", hvcsd->p_unit_address);
-       spin_unlock_irqrestore(&hvcsd->lock, flags);
-       return retval;
-}
-static DEVICE_ATTR(partner_vtys, S_IRUGO, hvcs_partner_vtys_show, NULL);
-
-static ssize_t hvcs_partner_clcs_show(struct device *dev, struct device_attribute *attr, char *buf)
-{
-       struct vio_dev *viod = to_vio_dev(dev);
-       struct hvcs_struct *hvcsd = from_vio_dev(viod);
-       unsigned long flags;
-       int retval;
-
-       spin_lock_irqsave(&hvcsd->lock, flags);
-       retval = sprintf(buf, "%s\n", &hvcsd->p_location_code[0]);
-       spin_unlock_irqrestore(&hvcsd->lock, flags);
-       return retval;
-}
-static DEVICE_ATTR(partner_clcs, S_IRUGO, hvcs_partner_clcs_show, NULL);
-
-static ssize_t hvcs_current_vty_store(struct device *dev, struct device_attribute *attr, const char * buf,
-               size_t count)
-{
-       /*
-        * Don't need this feature at the present time because firmware doesn't
-        * yet support multiple partners.
-        */
-       printk(KERN_INFO "HVCS: Denied current_vty change: -EPERM.\n");
-       return -EPERM;
-}
-
-static ssize_t hvcs_current_vty_show(struct device *dev, struct device_attribute *attr, char *buf)
-{
-       struct vio_dev *viod = to_vio_dev(dev);
-       struct hvcs_struct *hvcsd = from_vio_dev(viod);
-       unsigned long flags;
-       int retval;
-
-       spin_lock_irqsave(&hvcsd->lock, flags);
-       retval = sprintf(buf, "%s\n", &hvcsd->p_location_code[0]);
-       spin_unlock_irqrestore(&hvcsd->lock, flags);
-       return retval;
-}
-
-static DEVICE_ATTR(current_vty,
-       S_IRUGO | S_IWUSR, hvcs_current_vty_show, hvcs_current_vty_store);
-
-static ssize_t hvcs_vterm_state_store(struct device *dev, struct device_attribute *attr, const char *buf,
-               size_t count)
-{
-       struct vio_dev *viod = to_vio_dev(dev);
-       struct hvcs_struct *hvcsd = from_vio_dev(viod);
-       unsigned long flags;
-
-       /* writing a '0' to this sysfs entry will result in the disconnect. */
-       if (simple_strtol(buf, NULL, 0) != 0)
-               return -EINVAL;
-
-       spin_lock_irqsave(&hvcsd->lock, flags);
-
-       if (hvcsd->open_count > 0) {
-               spin_unlock_irqrestore(&hvcsd->lock, flags);
-               printk(KERN_INFO "HVCS: vterm state unchanged.  "
-                               "The hvcs device node is still in use.\n");
-               return -EPERM;
-       }
-
-       if (hvcsd->connected == 0) {
-               spin_unlock_irqrestore(&hvcsd->lock, flags);
-               printk(KERN_INFO "HVCS: vterm state unchanged. The"
-                               " vty-server is not connected to a vty.\n");
-               return -EPERM;
-       }
-
-       hvcs_partner_free(hvcsd);
-       printk(KERN_INFO "HVCS: Closed vty-server@%X and"
-                       " partner vty@%X:%d connection.\n",
-                       hvcsd->vdev->unit_address,
-                       hvcsd->p_unit_address,
-                       (uint32_t)hvcsd->p_partition_ID);
-
-       spin_unlock_irqrestore(&hvcsd->lock, flags);
-       return count;
-}
-
-static ssize_t hvcs_vterm_state_show(struct device *dev, struct device_attribute *attr, char *buf)
-{
-       struct vio_dev *viod = to_vio_dev(dev);
-       struct hvcs_struct *hvcsd = from_vio_dev(viod);
-       unsigned long flags;
-       int retval;
-
-       spin_lock_irqsave(&hvcsd->lock, flags);
-       retval = sprintf(buf, "%d\n", hvcsd->connected);
-       spin_unlock_irqrestore(&hvcsd->lock, flags);
-       return retval;
-}
-static DEVICE_ATTR(vterm_state, S_IRUGO | S_IWUSR,
-               hvcs_vterm_state_show, hvcs_vterm_state_store);
-
-static ssize_t hvcs_index_show(struct device *dev, struct device_attribute *attr, char *buf)
-{
-       struct vio_dev *viod = to_vio_dev(dev);
-       struct hvcs_struct *hvcsd = from_vio_dev(viod);
-       unsigned long flags;
-       int retval;
-
-       spin_lock_irqsave(&hvcsd->lock, flags);
-       retval = sprintf(buf, "%d\n", hvcsd->index);
-       spin_unlock_irqrestore(&hvcsd->lock, flags);
-       return retval;
-}
-
-static DEVICE_ATTR(index, S_IRUGO, hvcs_index_show, NULL);
-
-static struct attribute *hvcs_attrs[] = {
-       &dev_attr_partner_vtys.attr,
-       &dev_attr_partner_clcs.attr,
-       &dev_attr_current_vty.attr,
-       &dev_attr_vterm_state.attr,
-       &dev_attr_index.attr,
-       NULL,
-};
-
-static struct attribute_group hvcs_attr_group = {
-       .attrs = hvcs_attrs,
-};
-
-static ssize_t hvcs_rescan_show(struct device_driver *ddp, char *buf)
-{
-       /* A 1 means it is updating, a 0 means it is done updating */
-       return snprintf(buf, PAGE_SIZE, "%d\n", hvcs_rescan_status);
-}
-
-static ssize_t hvcs_rescan_store(struct device_driver *ddp, const char * buf,
-               size_t count)
-{
-       if ((simple_strtol(buf, NULL, 0) != 1)
-               && (hvcs_rescan_status != 0))
-               return -EINVAL;
-
-       hvcs_rescan_status = 1;
-       printk(KERN_INFO "HVCS: rescanning partner info for all"
-               " vty-servers.\n");
-       hvcs_rescan_devices_list();
-       hvcs_rescan_status = 0;
-       return count;
-}
-
-static DRIVER_ATTR(rescan,
-       S_IRUGO | S_IWUSR, hvcs_rescan_show, hvcs_rescan_store);
-
-static void hvcs_kick(void)
-{
-       hvcs_kicked = 1;
-       wmb();
-       wake_up_process(hvcs_task);
-}
-
-static void hvcs_unthrottle(struct tty_struct *tty)
-{
-       struct hvcs_struct *hvcsd = tty->driver_data;
-       unsigned long flags;
-
-       spin_lock_irqsave(&hvcsd->lock, flags);
-       hvcsd->todo_mask |= HVCS_SCHED_READ;
-       spin_unlock_irqrestore(&hvcsd->lock, flags);
-       hvcs_kick();
-}
-
-static void hvcs_throttle(struct tty_struct *tty)
-{
-       struct hvcs_struct *hvcsd = tty->driver_data;
-       unsigned long flags;
-
-       spin_lock_irqsave(&hvcsd->lock, flags);
-       vio_disable_interrupts(hvcsd->vdev);
-       spin_unlock_irqrestore(&hvcsd->lock, flags);
-}
-
-/*
- * If the device is being removed we don't have to worry about this interrupt
- * handler taking any further interrupts because they are disabled which means
- * the hvcs_struct will always be valid in this handler.
- */
-static irqreturn_t hvcs_handle_interrupt(int irq, void *dev_instance)
-{
-       struct hvcs_struct *hvcsd = dev_instance;
-
-       spin_lock(&hvcsd->lock);
-       vio_disable_interrupts(hvcsd->vdev);
-       hvcsd->todo_mask |= HVCS_SCHED_READ;
-       spin_unlock(&hvcsd->lock);
-       hvcs_kick();
-
-       return IRQ_HANDLED;
-}
-
-/* This function must be called with the hvcsd->lock held */
-static void hvcs_try_write(struct hvcs_struct *hvcsd)
-{
-       uint32_t unit_address = hvcsd->vdev->unit_address;
-       struct tty_struct *tty = hvcsd->tty;
-       int sent;
-
-       if (hvcsd->todo_mask & HVCS_TRY_WRITE) {
-               /* won't send partial writes */
-               sent = hvc_put_chars(unit_address,
-                               &hvcsd->buffer[0],
-                               hvcsd->chars_in_buffer );
-               if (sent > 0) {
-                       hvcsd->chars_in_buffer = 0;
-                       /* wmb(); */
-                       hvcsd->todo_mask &= ~(HVCS_TRY_WRITE);
-                       /* wmb(); */
-
-                       /*
-                        * We are still obligated to deliver the data to the
-                        * hypervisor even if the tty has been closed because
-                        * we commited to delivering it.  But don't try to wake
-                        * a non-existent tty.
-                        */
-                       if (tty) {
-                               tty_wakeup(tty);
-                       }
-               }
-       }
-}
-
-static int hvcs_io(struct hvcs_struct *hvcsd)
-{
-       uint32_t unit_address;
-       struct tty_struct *tty;
-       char buf[HVCS_BUFF_LEN] __ALIGNED__;
-       unsigned long flags;
-       int got = 0;
-
-       spin_lock_irqsave(&hvcsd->lock, flags);
-
-       unit_address = hvcsd->vdev->unit_address;
-       tty = hvcsd->tty;
-
-       hvcs_try_write(hvcsd);
-
-       if (!tty || test_bit(TTY_THROTTLED, &tty->flags)) {
-               hvcsd->todo_mask &= ~(HVCS_READ_MASK);
-               goto bail;
-       } else if (!(hvcsd->todo_mask & (HVCS_READ_MASK)))
-               goto bail;
-
-       /* remove the read masks */
-       hvcsd->todo_mask &= ~(HVCS_READ_MASK);
-
-       if (tty_buffer_request_room(tty, HVCS_BUFF_LEN) >= HVCS_BUFF_LEN) {
-               got = hvc_get_chars(unit_address,
-                               &buf[0],
-                               HVCS_BUFF_LEN);
-               tty_insert_flip_string(tty, buf, got);
-       }
-
-       /* Give the TTY time to process the data we just sent. */
-       if (got)
-               hvcsd->todo_mask |= HVCS_QUICK_READ;
-
-       spin_unlock_irqrestore(&hvcsd->lock, flags);
-       /* This is synch because tty->low_latency == 1 */
-       if(got)
-               tty_flip_buffer_push(tty);
-
-       if (!got) {
-               /* Do this _after_ the flip_buffer_push */
-               spin_lock_irqsave(&hvcsd->lock, flags);
-               vio_enable_interrupts(hvcsd->vdev);
-               spin_unlock_irqrestore(&hvcsd->lock, flags);
-       }
-
-       return hvcsd->todo_mask;
-
- bail:
-       spin_unlock_irqrestore(&hvcsd->lock, flags);
-       return hvcsd->todo_mask;
-}
-
-static int khvcsd(void *unused)
-{
-       struct hvcs_struct *hvcsd;
-       int hvcs_todo_mask;
-
-       __set_current_state(TASK_RUNNING);
-
-       do {
-               hvcs_todo_mask = 0;
-               hvcs_kicked = 0;
-               wmb();
-
-               spin_lock(&hvcs_structs_lock);
-               list_for_each_entry(hvcsd, &hvcs_structs, next) {
-                       hvcs_todo_mask |= hvcs_io(hvcsd);
-               }
-               spin_unlock(&hvcs_structs_lock);
-
-               /*
-                * If any of the hvcs adapters want to try a write or quick read
-                * don't schedule(), yield a smidgen then execute the hvcs_io
-                * thread again for those that want the write.
-                */
-                if (hvcs_todo_mask & (HVCS_TRY_WRITE | HVCS_QUICK_READ)) {
-                       yield();
-                       continue;
-               }
-
-               set_current_state(TASK_INTERRUPTIBLE);
-               if (!hvcs_kicked)
-                       schedule();
-               __set_current_state(TASK_RUNNING);
-       } while (!kthread_should_stop());
-
-       return 0;
-}
-
-static struct vio_device_id hvcs_driver_table[] __devinitdata= {
-       {"serial-server", "hvterm2"},
-       { "", "" }
-};
-MODULE_DEVICE_TABLE(vio, hvcs_driver_table);
-
-static void hvcs_return_index(int index)
-{
-       /* Paranoia check */
-       if (!hvcs_index_list)
-               return;
-       if (index < 0 || index >= hvcs_index_count)
-               return;
-       if (hvcs_index_list[index] == -1)
-               return;
-       else
-               hvcs_index_list[index] = -1;
-}
-
-/* callback when the kref ref count reaches zero */
-static void destroy_hvcs_struct(struct kref *kref)
-{
-       struct hvcs_struct *hvcsd = from_kref(kref);
-       struct vio_dev *vdev;
-       unsigned long flags;
-
-       spin_lock(&hvcs_structs_lock);
-       spin_lock_irqsave(&hvcsd->lock, flags);
-
-       /* the list_del poisons the pointers */
-       list_del(&(hvcsd->next));
-
-       if (hvcsd->connected == 1) {
-               hvcs_partner_free(hvcsd);
-               printk(KERN_INFO "HVCS: Closed vty-server@%X and"
-                               " partner vty@%X:%d connection.\n",
-                               hvcsd->vdev->unit_address,
-                               hvcsd->p_unit_address,
-                               (uint32_t)hvcsd->p_partition_ID);
-       }
-       printk(KERN_INFO "HVCS: Destroyed hvcs_struct for vty-server@%X.\n",
-                       hvcsd->vdev->unit_address);
-
-       vdev = hvcsd->vdev;
-       hvcsd->vdev = NULL;
-
-       hvcsd->p_unit_address = 0;
-       hvcsd->p_partition_ID = 0;
-       hvcs_return_index(hvcsd->index);
-       memset(&hvcsd->p_location_code[0], 0x00, HVCS_CLC_LENGTH + 1);
-
-       spin_unlock_irqrestore(&hvcsd->lock, flags);
-       spin_unlock(&hvcs_structs_lock);
-
-       sysfs_remove_group(&vdev->dev.kobj, &hvcs_attr_group);
-
-       kfree(hvcsd);
-}
-
-static int hvcs_get_index(void)
-{
-       int i;
-       /* Paranoia check */
-       if (!hvcs_index_list) {
-               printk(KERN_ERR "HVCS: hvcs_index_list NOT valid!.\n");
-               return -EFAULT;
-       }
-       /* Find the numerically lowest first free index. */
-       for(i = 0; i < hvcs_index_count; i++) {
-               if (hvcs_index_list[i] == -1) {
-                       hvcs_index_list[i] = 0;
-                       return i;
-               }
-       }
-       return -1;
-}
-
-static int __devinit hvcs_probe(
-       struct vio_dev *dev,
-       const struct vio_device_id *id)
-{
-       struct hvcs_struct *hvcsd;
-       int index;
-       int retval;
-
-       if (!dev || !id) {
-               printk(KERN_ERR "HVCS: probed with invalid parameter.\n");
-               return -EPERM;
-       }
-
-       /* early to avoid cleanup on failure */
-       index = hvcs_get_index();
-       if (index < 0) {
-               return -EFAULT;
-       }
-
-       hvcsd = kzalloc(sizeof(*hvcsd), GFP_KERNEL);
-       if (!hvcsd)
-               return -ENODEV;
-
-
-       spin_lock_init(&hvcsd->lock);
-       /* Automatically incs the refcount the first time */
-       kref_init(&hvcsd->kref);
-
-       hvcsd->vdev = dev;
-       dev_set_drvdata(&dev->dev, hvcsd);
-
-       hvcsd->index = index;
-
-       /* hvcsd->index = ++hvcs_struct_count; */
-       hvcsd->chars_in_buffer = 0;
-       hvcsd->todo_mask = 0;
-       hvcsd->connected = 0;
-
-       /*
-        * This will populate the hvcs_struct's partner info fields for the
-        * first time.
-        */
-       if (hvcs_get_pi(hvcsd)) {
-               printk(KERN_ERR "HVCS: Failed to fetch partner"
-                       " info for vty-server@%X on device probe.\n",
-                       hvcsd->vdev->unit_address);
-       }
-
-       /*
-        * If a user app opens a tty that corresponds to this vty-server before
-        * the hvcs_struct has been added to the devices list then the user app
-        * will get -ENODEV.
-        */
-       spin_lock(&hvcs_structs_lock);
-       list_add_tail(&(hvcsd->next), &hvcs_structs);
-       spin_unlock(&hvcs_structs_lock);
-
-       retval = sysfs_create_group(&dev->dev.kobj, &hvcs_attr_group);
-       if (retval) {
-               printk(KERN_ERR "HVCS: Can't create sysfs attrs for vty-server@%X\n",
-                      hvcsd->vdev->unit_address);
-               return retval;
-       }
-
-       printk(KERN_INFO "HVCS: vty-server@%X added to the vio bus.\n", dev->unit_address);
-
-       /*
-        * DON'T enable interrupts here because there is no user to receive the
-        * data.
-        */
-       return 0;
-}
-
-static int __devexit hvcs_remove(struct vio_dev *dev)
-{
-       struct hvcs_struct *hvcsd = dev_get_drvdata(&dev->dev);
-       unsigned long flags;
-       struct tty_struct *tty;
-
-       if (!hvcsd)
-               return -ENODEV;
-
-       /* By this time the vty-server won't be getting any more interrupts */
-
-       spin_lock_irqsave(&hvcsd->lock, flags);
-
-       tty = hvcsd->tty;
-
-       spin_unlock_irqrestore(&hvcsd->lock, flags);
-
-       /*
-        * Let the last holder of this object cause it to be removed, which
-        * would probably be tty_hangup below.
-        */
-       kref_put(&hvcsd->kref, destroy_hvcs_struct);
-
-       /*
-        * The hangup is a scheduled function which will auto chain call
-        * hvcs_hangup.  The tty should always be valid at this time unless a
-        * simultaneous tty close already cleaned up the hvcs_struct.
-        */
-       if (tty)
-               tty_hangup(tty);
-
-       printk(KERN_INFO "HVCS: vty-server@%X removed from the"
-                       " vio bus.\n", dev->unit_address);
-       return 0;
-};
-
-static struct vio_driver hvcs_vio_driver = {
-       .id_table       = hvcs_driver_table,
-       .probe          = hvcs_probe,
-       .remove         = __devexit_p(hvcs_remove),
-       .driver         = {
-               .name   = hvcs_driver_name,
-               .owner  = THIS_MODULE,
-       }
-};
-
-/* Only called from hvcs_get_pi please */
-static void hvcs_set_pi(struct hvcs_partner_info *pi, struct hvcs_struct *hvcsd)
-{
-       int clclength;
-
-       hvcsd->p_unit_address = pi->unit_address;
-       hvcsd->p_partition_ID  = pi->partition_ID;
-       clclength = strlen(&pi->location_code[0]);
-       if (clclength > HVCS_CLC_LENGTH)
-               clclength = HVCS_CLC_LENGTH;
-
-       /* copy the null-term char too */
-       strncpy(&hvcsd->p_location_code[0],
-                       &pi->location_code[0], clclength + 1);
-}
-
-/*
- * Traverse the list and add the partner info that is found to the hvcs_struct
- * struct entry. NOTE: At this time I know that partner info will return a
- * single entry but in the future there may be multiple partner info entries per
- * vty-server and you'll want to zero out that list and reset it.  If for some
- * reason you have an old version of this driver but there IS more than one
- * partner info then hvcsd->p_* will hold the last partner info data from the
- * firmware query.  A good way to update this code would be to replace the three
- * partner info fields in hvcs_struct with a list of hvcs_partner_info
- * instances.
- *
- * This function must be called with the hvcsd->lock held.
- */
-static int hvcs_get_pi(struct hvcs_struct *hvcsd)
-{
-       struct hvcs_partner_info *pi;
-       uint32_t unit_address = hvcsd->vdev->unit_address;
-       struct list_head head;
-       int retval;
-
-       spin_lock(&hvcs_pi_lock);
-       if (!hvcs_pi_buff) {
-               spin_unlock(&hvcs_pi_lock);
-               return -EFAULT;
-       }
-       retval = hvcs_get_partner_info(unit_address, &head, hvcs_pi_buff);
-       spin_unlock(&hvcs_pi_lock);
-       if (retval) {
-               printk(KERN_ERR "HVCS: Failed to fetch partner"
-                       " info for vty-server@%x.\n", unit_address);
-               return retval;
-       }
-
-       /* nixes the values if the partner vty went away */
-       hvcsd->p_unit_address = 0;
-       hvcsd->p_partition_ID = 0;
-
-       list_for_each_entry(pi, &head, node)
-               hvcs_set_pi(pi, hvcsd);
-
-       hvcs_free_partner_info(&head);
-       return 0;
-}
-
-/*
- * This function is executed by the driver "rescan" sysfs entry.  It shouldn't
- * be executed elsewhere, in order to prevent deadlock issues.
- */
-static int hvcs_rescan_devices_list(void)
-{
-       struct hvcs_struct *hvcsd;
-       unsigned long flags;
-
-       spin_lock(&hvcs_structs_lock);
-
-       list_for_each_entry(hvcsd, &hvcs_structs, next) {
-               spin_lock_irqsave(&hvcsd->lock, flags);
-               hvcs_get_pi(hvcsd);
-               spin_unlock_irqrestore(&hvcsd->lock, flags);
-       }
-
-       spin_unlock(&hvcs_structs_lock);
-
-       return 0;
-}
-
-/*
- * Farm this off into its own function because it could be more complex once
- * multiple partners support is added. This function should be called with
- * the hvcsd->lock held.
- */
-static int hvcs_has_pi(struct hvcs_struct *hvcsd)
-{
-       if ((!hvcsd->p_unit_address) || (!hvcsd->p_partition_ID))
-               return 0;
-       return 1;
-}
-
-/*
- * NOTE: It is possible that the super admin removed a partner vty and then
- * added a different vty as the new partner.
- *
- * This function must be called with the hvcsd->lock held.
- */
-static int hvcs_partner_connect(struct hvcs_struct *hvcsd)
-{
-       int retval;
-       unsigned int unit_address = hvcsd->vdev->unit_address;
-
-       /*
-        * If there wasn't any pi when the device was added it doesn't meant
-        * there isn't any now.  This driver isn't notified when a new partner
-        * vty is added to a vty-server so we discover changes on our own.
-        * Please see comments in hvcs_register_connection() for justification
-        * of this bizarre code.
-        */
-       retval = hvcs_register_connection(unit_address,
-                       hvcsd->p_partition_ID,
-                       hvcsd->p_unit_address);
-       if (!retval) {
-               hvcsd->connected = 1;
-               return 0;
-       } else if (retval != -EINVAL)
-               return retval;
-
-       /*
-        * As per the spec re-get the pi and try again if -EINVAL after the
-        * first connection attempt.
-        */
-       if (hvcs_get_pi(hvcsd))
-               return -ENOMEM;
-
-       if (!hvcs_has_pi(hvcsd))
-               return -ENODEV;
-
-       retval = hvcs_register_connection(unit_address,
-                       hvcsd->p_partition_ID,
-                       hvcsd->p_unit_address);
-       if (retval != -EINVAL) {
-               hvcsd->connected = 1;
-               return retval;
-       }
-
-       /*
-        * EBUSY is the most likely scenario though the vty could have been
-        * removed or there really could be an hcall error due to the parameter
-        * data but thanks to ambiguous firmware return codes we can't really
-        * tell.
-        */
-       printk(KERN_INFO "HVCS: vty-server or partner"
-                       " vty is busy.  Try again later.\n");
-       return -EBUSY;
-}
-
-/* This function must be called with the hvcsd->lock held */
-static void hvcs_partner_free(struct hvcs_struct *hvcsd)
-{
-       int retval;
-       do {
-               retval = hvcs_free_connection(hvcsd->vdev->unit_address);
-       } while (retval == -EBUSY);
-       hvcsd->connected = 0;
-}
-
-/* This helper function must be called WITHOUT the hvcsd->lock held */
-static int hvcs_enable_device(struct hvcs_struct *hvcsd, uint32_t unit_address,
-               unsigned int irq, struct vio_dev *vdev)
-{
-       unsigned long flags;
-       int rc;
-
-       /*
-        * It is possible that the vty-server was removed between the time that
-        * the conn was registered and now.
-        */
-       if (!(rc = request_irq(irq, &hvcs_handle_interrupt,
-                               IRQF_DISABLED, "ibmhvcs", hvcsd))) {
-               /*
-                * It is possible the vty-server was removed after the irq was
-                * requested but before we have time to enable interrupts.
-                */
-               if (vio_enable_interrupts(vdev) == H_SUCCESS)
-                       return 0;
-               else {
-                       printk(KERN_ERR "HVCS: int enable failed for"
-                                       " vty-server@%X.\n", unit_address);
-                       free_irq(irq, hvcsd);
-               }
-       } else
-               printk(KERN_ERR "HVCS: irq req failed for"
-                               " vty-server@%X.\n", unit_address);
-
-       spin_lock_irqsave(&hvcsd->lock, flags);
-       hvcs_partner_free(hvcsd);
-       spin_unlock_irqrestore(&hvcsd->lock, flags);
-
-       return rc;
-
-}
-
-/*
- * This always increments the kref ref count if the call is successful.
- * Please remember to dec when you are done with the instance.
- *
- * NOTICE: Do NOT hold either the hvcs_struct.lock or hvcs_structs_lock when
- * calling this function or you will get deadlock.
- */
-static struct hvcs_struct *hvcs_get_by_index(int index)
-{
-       struct hvcs_struct *hvcsd = NULL;
-       unsigned long flags;
-
-       spin_lock(&hvcs_structs_lock);
-       /* We can immediately discard OOB requests */
-       if (index >= 0 && index < HVCS_MAX_SERVER_ADAPTERS) {
-               list_for_each_entry(hvcsd, &hvcs_structs, next) {
-                       spin_lock_irqsave(&hvcsd->lock, flags);
-                       if (hvcsd->index == index) {
-                               kref_get(&hvcsd->kref);
-                               spin_unlock_irqrestore(&hvcsd->lock, flags);
-                               spin_unlock(&hvcs_structs_lock);
-                               return hvcsd;
-                       }
-                       spin_unlock_irqrestore(&hvcsd->lock, flags);
-               }
-               hvcsd = NULL;
-       }
-
-       spin_unlock(&hvcs_structs_lock);
-       return hvcsd;
-}
-
-/*
- * This is invoked via the tty_open interface when a user app connects to the
- * /dev node.
- */
-static int hvcs_open(struct tty_struct *tty, struct file *filp)
-{
-       struct hvcs_struct *hvcsd;
-       int rc, retval = 0;
-       unsigned long flags;
-       unsigned int irq;
-       struct vio_dev *vdev;
-       unsigned long unit_address;
-
-       if (tty->driver_data)
-               goto fast_open;
-
-       /*
-        * Is there a vty-server that shares the same index?
-        * This function increments the kref index.
-        */
-       if (!(hvcsd = hvcs_get_by_index(tty->index))) {
-               printk(KERN_WARNING "HVCS: open failed, no device associated"
-                               " with tty->index %d.\n", tty->index);
-               return -ENODEV;
-       }
-
-       spin_lock_irqsave(&hvcsd->lock, flags);
-
-       if (hvcsd->connected == 0)
-               if ((retval = hvcs_partner_connect(hvcsd)))
-                       goto error_release;
-
-       hvcsd->open_count = 1;
-       hvcsd->tty = tty;
-       tty->driver_data = hvcsd;
-
-       memset(&hvcsd->buffer[0], 0x00, HVCS_BUFF_LEN);
-
-       /*
-        * Save these in the spinlock for the enable operations that need them
-        * outside of the spinlock.
-        */
-       irq = hvcsd->vdev->irq;
-       vdev = hvcsd->vdev;
-       unit_address = hvcsd->vdev->unit_address;
-
-       hvcsd->todo_mask |= HVCS_SCHED_READ;
-       spin_unlock_irqrestore(&hvcsd->lock, flags);
-
-       /*
-        * This must be done outside of the spinlock because it requests irqs
-        * and will grab the spinlock and free the connection if it fails.
-        */
-       if (((rc = hvcs_enable_device(hvcsd, unit_address, irq, vdev)))) {
-               kref_put(&hvcsd->kref, destroy_hvcs_struct);
-               printk(KERN_WARNING "HVCS: enable device failed.\n");
-               return rc;
-       }
-
-       goto open_success;
-
-fast_open:
-       hvcsd = tty->driver_data;
-
-       spin_lock_irqsave(&hvcsd->lock, flags);
-       kref_get(&hvcsd->kref);
-       hvcsd->open_count++;
-       hvcsd->todo_mask |= HVCS_SCHED_READ;
-       spin_unlock_irqrestore(&hvcsd->lock, flags);
-
-open_success:
-       hvcs_kick();
-
-       printk(KERN_INFO "HVCS: vty-server@%X connection opened.\n",
-               hvcsd->vdev->unit_address );
-
-       return 0;
-
-error_release:
-       spin_unlock_irqrestore(&hvcsd->lock, flags);
-       kref_put(&hvcsd->kref, destroy_hvcs_struct);
-
-       printk(KERN_WARNING "HVCS: partner connect failed.\n");
-       return retval;
-}
-
-static void hvcs_close(struct tty_struct *tty, struct file *filp)
-{
-       struct hvcs_struct *hvcsd;
-       unsigned long flags;
-       int irq = NO_IRQ;
-
-       /*
-        * Is someone trying to close the file associated with this device after
-        * we have hung up?  If so tty->driver_data wouldn't be valid.
-        */
-       if (tty_hung_up_p(filp))
-               return;
-
-       /*
-        * No driver_data means that this close was probably issued after a
-        * failed hvcs_open by the tty layer's release_dev() api and we can just
-        * exit cleanly.
-        */
-       if (!tty->driver_data)
-               return;
-
-       hvcsd = tty->driver_data;
-
-       spin_lock_irqsave(&hvcsd->lock, flags);
-       if (--hvcsd->open_count == 0) {
-
-               vio_disable_interrupts(hvcsd->vdev);
-
-               /*
-                * NULL this early so that the kernel_thread doesn't try to
-                * execute any operations on the TTY even though it is obligated
-                * to deliver any pending I/O to the hypervisor.
-                */
-               hvcsd->tty = NULL;
-
-               irq = hvcsd->vdev->irq;
-               spin_unlock_irqrestore(&hvcsd->lock, flags);
-
-               tty_wait_until_sent(tty, HVCS_CLOSE_WAIT);
-
-               /*
-                * This line is important because it tells hvcs_open that this
-                * device needs to be re-configured the next time hvcs_open is
-                * called.
-                */
-               tty->driver_data = NULL;
-
-               free_irq(irq, hvcsd);
-               kref_put(&hvcsd->kref, destroy_hvcs_struct);
-               return;
-       } else if (hvcsd->open_count < 0) {
-               printk(KERN_ERR "HVCS: vty-server@%X open_count: %d"
-                               " is missmanaged.\n",
-               hvcsd->vdev->unit_address, hvcsd->open_count);
-       }
-
-       spin_unlock_irqrestore(&hvcsd->lock, flags);
-       kref_put(&hvcsd->kref, destroy_hvcs_struct);
-}
-
-static void hvcs_hangup(struct tty_struct * tty)
-{
-       struct hvcs_struct *hvcsd = tty->driver_data;
-       unsigned long flags;
-       int temp_open_count;
-       int irq = NO_IRQ;
-
-       spin_lock_irqsave(&hvcsd->lock, flags);
-       /* Preserve this so that we know how many kref refs to put */
-       temp_open_count = hvcsd->open_count;
-
-       /*
-        * Don't kref put inside the spinlock because the destruction
-        * callback may use the spinlock and it may get called before the
-        * spinlock has been released.
-        */
-       vio_disable_interrupts(hvcsd->vdev);
-
-       hvcsd->todo_mask = 0;
-
-       /* I don't think the tty needs the hvcs_struct pointer after a hangup */
-       hvcsd->tty->driver_data = NULL;
-       hvcsd->tty = NULL;
-
-       hvcsd->open_count = 0;
-
-       /* This will drop any buffered data on the floor which is OK in a hangup
-        * scenario. */
-       memset(&hvcsd->buffer[0], 0x00, HVCS_BUFF_LEN);
-       hvcsd->chars_in_buffer = 0;
-
-       irq = hvcsd->vdev->irq;
-
-       spin_unlock_irqrestore(&hvcsd->lock, flags);
-
-       free_irq(irq, hvcsd);
-
-       /*
-        * We need to kref_put() for every open_count we have since the
-        * tty_hangup() function doesn't invoke a close per open connection on a
-        * non-console device.
-        */
-       while(temp_open_count) {
-               --temp_open_count;
-               /*
-                * The final put will trigger destruction of the hvcs_struct.
-                * NOTE:  If this hangup was signaled from user space then the
-                * final put will never happen.
-                */
-               kref_put(&hvcsd->kref, destroy_hvcs_struct);
-       }
-}
-
-/*
- * NOTE: This is almost always from_user since user level apps interact with the
- * /dev nodes. I'm trusting that if hvcs_write gets called and interrupted by
- * hvcs_remove (which removes the target device and executes tty_hangup()) that
- * tty_hangup will allow hvcs_write time to complete execution before it
- * terminates our device.
- */
-static int hvcs_write(struct tty_struct *tty,
-               const unsigned char *buf, int count)
-{
-       struct hvcs_struct *hvcsd = tty->driver_data;
-       unsigned int unit_address;
-       const unsigned char *charbuf;
-       unsigned long flags;
-       int total_sent = 0;
-       int tosend = 0;
-       int result = 0;
-
-       /*
-        * If they don't check the return code off of their open they may
-        * attempt this even if there is no connected device.
-        */
-       if (!hvcsd)
-               return -ENODEV;
-
-       /* Reasonable size to prevent user level flooding */
-       if (count > HVCS_MAX_FROM_USER) {
-               printk(KERN_WARNING "HVCS write: count being truncated to"
-                               " HVCS_MAX_FROM_USER.\n");
-               count = HVCS_MAX_FROM_USER;
-       }
-
-       charbuf = buf;
-
-       spin_lock_irqsave(&hvcsd->lock, flags);
-
-       /*
-        * Somehow an open succedded but the device was removed or the
-        * connection terminated between the vty-server and partner vty during
-        * the middle of a write operation?  This is a crummy place to do this
-        * but we want to keep it all in the spinlock.
-        */
-       if (hvcsd->open_count <= 0) {
-               spin_unlock_irqrestore(&hvcsd->lock, flags);
-               return -ENODEV;
-       }
-
-       unit_address = hvcsd->vdev->unit_address;
-
-       while (count > 0) {
-               tosend = min(count, (HVCS_BUFF_LEN - hvcsd->chars_in_buffer));
-               /*
-                * No more space, this probably means that the last call to
-                * hvcs_write() didn't succeed and the buffer was filled up.
-                */
-               if (!tosend)
-                       break;
-
-               memcpy(&hvcsd->buffer[hvcsd->chars_in_buffer],
-                               &charbuf[total_sent],
-                               tosend);
-
-               hvcsd->chars_in_buffer += tosend;
-
-               result = 0;
-
-               /*
-                * If this is true then we don't want to try writing to the
-                * hypervisor because that is the kernel_threads job now.  We'll
-                * just add to the buffer.
-                */
-               if (!(hvcsd->todo_mask & HVCS_TRY_WRITE))
-                       /* won't send partial writes */
-                       result = hvc_put_chars(unit_address,
-                                       &hvcsd->buffer[0],
-                                       hvcsd->chars_in_buffer);
-
-               /*
-                * Since we know we have enough room in hvcsd->buffer for
-                * tosend we record that it was sent regardless of whether the
-                * hypervisor actually took it because we have it buffered.
-                */
-               total_sent+=tosend;
-               count-=tosend;
-               if (result == 0) {
-                       hvcsd->todo_mask |= HVCS_TRY_WRITE;
-                       hvcs_kick();
-                       break;
-               }
-
-               hvcsd->chars_in_buffer = 0;
-               /*
-                * Test after the chars_in_buffer reset otherwise this could
-                * deadlock our writes if hvc_put_chars fails.
-                */
-               if (result < 0)
-                       break;
-       }
-
-       spin_unlock_irqrestore(&hvcsd->lock, flags);
-
-       if (result == -1)
-               return -EIO;
-       else
-               return total_sent;
-}
-
-/*
- * This is really asking how much can we guarentee that we can send or that we
- * absolutely WILL BUFFER if we can't send it.  This driver MUST honor the
- * return value, hence the reason for hvcs_struct buffering.
- */
-static int hvcs_write_room(struct tty_struct *tty)
-{
-       struct hvcs_struct *hvcsd = tty->driver_data;
-
-       if (!hvcsd || hvcsd->open_count <= 0)
-               return 0;
-
-       return HVCS_BUFF_LEN - hvcsd->chars_in_buffer;
-}
-
-static int hvcs_chars_in_buffer(struct tty_struct *tty)
-{
-       struct hvcs_struct *hvcsd = tty->driver_data;
-
-       return hvcsd->chars_in_buffer;
-}
-
-static const struct tty_operations hvcs_ops = {
-       .open = hvcs_open,
-       .close = hvcs_close,
-       .hangup = hvcs_hangup,
-       .write = hvcs_write,
-       .write_room = hvcs_write_room,
-       .chars_in_buffer = hvcs_chars_in_buffer,
-       .unthrottle = hvcs_unthrottle,
-       .throttle = hvcs_throttle,
-};
-
-static int hvcs_alloc_index_list(int n)
-{
-       int i;
-
-       hvcs_index_list = kmalloc(n * sizeof(hvcs_index_count),GFP_KERNEL);
-       if (!hvcs_index_list)
-               return -ENOMEM;
-       hvcs_index_count = n;
-       for (i = 0; i < hvcs_index_count; i++)
-               hvcs_index_list[i] = -1;
-       return 0;
-}
-
-static void hvcs_free_index_list(void)
-{
-       /* Paranoia check to be thorough. */
-       kfree(hvcs_index_list);
-       hvcs_index_list = NULL;
-       hvcs_index_count = 0;
-}
-
-static int __init hvcs_module_init(void)
-{
-       int rc;
-       int num_ttys_to_alloc;
-
-       printk(KERN_INFO "Initializing %s\n", hvcs_driver_string);
-
-       /* Has the user specified an overload with an insmod param? */
-       if (hvcs_parm_num_devs <= 0 ||
-               (hvcs_parm_num_devs > HVCS_MAX_SERVER_ADAPTERS)) {
-               num_ttys_to_alloc = HVCS_DEFAULT_SERVER_ADAPTERS;
-       } else
-               num_ttys_to_alloc = hvcs_parm_num_devs;
-
-       hvcs_tty_driver = alloc_tty_driver(num_ttys_to_alloc);
-       if (!hvcs_tty_driver)
-               return -ENOMEM;
-
-       if (hvcs_alloc_index_list(num_ttys_to_alloc)) {
-               rc = -ENOMEM;
-               goto index_fail;
-       }
-
-       hvcs_tty_driver->owner = THIS_MODULE;
-
-       hvcs_tty_driver->driver_name = hvcs_driver_name;
-       hvcs_tty_driver->name = hvcs_device_node;
-
-       /*
-        * We'll let the system assign us a major number, indicated by leaving
-        * it blank.
-        */
-
-       hvcs_tty_driver->minor_start = HVCS_MINOR_START;
-       hvcs_tty_driver->type = TTY_DRIVER_TYPE_SYSTEM;
-
-       /*
-        * We role our own so that we DONT ECHO.  We can't echo because the
-        * device we are connecting to already echoes by default and this would
-        * throw us into a horrible recursive echo-echo-echo loop.
-        */
-       hvcs_tty_driver->init_termios = hvcs_tty_termios;
-       hvcs_tty_driver->flags = TTY_DRIVER_REAL_RAW;
-
-       tty_set_operations(hvcs_tty_driver, &hvcs_ops);
-
-       /*
-        * The following call will result in sysfs entries that denote the
-        * dynamically assigned major and minor numbers for our devices.
-        */
-       if (tty_register_driver(hvcs_tty_driver)) {
-               printk(KERN_ERR "HVCS: registration as a tty driver failed.\n");
-               rc = -EIO;
-               goto register_fail;
-       }
-
-       hvcs_pi_buff = kmalloc(PAGE_SIZE, GFP_KERNEL);
-       if (!hvcs_pi_buff) {
-               rc = -ENOMEM;
-               goto buff_alloc_fail;
-       }
-
-       hvcs_task = kthread_run(khvcsd, NULL, "khvcsd");
-       if (IS_ERR(hvcs_task)) {
-               printk(KERN_ERR "HVCS: khvcsd creation failed.  Driver not loaded.\n");
-               rc = -EIO;
-               goto kthread_fail;
-       }
-
-       rc = vio_register_driver(&hvcs_vio_driver);
-       if (rc) {
-               printk(KERN_ERR "HVCS: can't register vio driver\n");
-               goto vio_fail;
-       }
-
-       /*
-        * This needs to be done AFTER the vio_register_driver() call or else
-        * the kobjects won't be initialized properly.
-        */
-       rc = driver_create_file(&(hvcs_vio_driver.driver), &driver_attr_rescan);
-       if (rc) {
-               printk(KERN_ERR "HVCS: sysfs attr create failed\n");
-               goto attr_fail;
-       }
-
-       printk(KERN_INFO "HVCS: driver module inserted.\n");
-
-       return 0;
-
-attr_fail:
-       vio_unregister_driver(&hvcs_vio_driver);
-vio_fail:
-       kthread_stop(hvcs_task);
-kthread_fail:
-       kfree(hvcs_pi_buff);
-buff_alloc_fail:
-       tty_unregister_driver(hvcs_tty_driver);
-register_fail:
-       hvcs_free_index_list();
-index_fail:
-       put_tty_driver(hvcs_tty_driver);
-       hvcs_tty_driver = NULL;
-       return rc;
-}
-
-static void __exit hvcs_module_exit(void)
-{
-       /*
-        * This driver receives hvcs_remove callbacks for each device upon
-        * module removal.
-        */
-
-       /*
-        * This synchronous operation  will wake the khvcsd kthread if it is
-        * asleep and will return when khvcsd has terminated.
-        */
-       kthread_stop(hvcs_task);
-
-       spin_lock(&hvcs_pi_lock);
-       kfree(hvcs_pi_buff);
-       hvcs_pi_buff = NULL;
-       spin_unlock(&hvcs_pi_lock);
-
-       driver_remove_file(&hvcs_vio_driver.driver, &driver_attr_rescan);
-
-       vio_unregister_driver(&hvcs_vio_driver);
-
-       tty_unregister_driver(hvcs_tty_driver);
-
-       hvcs_free_index_list();
-
-       put_tty_driver(hvcs_tty_driver);
-
-       printk(KERN_INFO "HVCS: driver module removed.\n");
-}
-
-module_init(hvcs_module_init);
-module_exit(hvcs_module_exit);
diff --git a/drivers/char/hvsi.c b/drivers/char/hvsi.c
deleted file mode 100644 (file)
index 67a75a5..0000000
+++ /dev/null
@@ -1,1314 +0,0 @@
-/*
- * Copyright (C) 2004 Hollis Blanchard <hollisb@us.ibm.com>, IBM
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
- */
-
-/* Host Virtual Serial Interface (HVSI) is a protocol between the hosted OS
- * and the service processor on IBM pSeries servers. On these servers, there
- * are no serial ports under the OS's control, and sometimes there is no other
- * console available either. However, the service processor has two standard
- * serial ports, so this over-complicated protocol allows the OS to control
- * those ports by proxy.
- *
- * Besides data, the procotol supports the reading/writing of the serial
- * port's DTR line, and the reading of the CD line. This is to allow the OS to
- * control a modem attached to the service processor's serial port. Note that
- * the OS cannot change the speed of the port through this protocol.
- */
-
-#undef DEBUG
-
-#include <linux/console.h>
-#include <linux/ctype.h>
-#include <linux/delay.h>
-#include <linux/init.h>
-#include <linux/interrupt.h>
-#include <linux/module.h>
-#include <linux/major.h>
-#include <linux/kernel.h>
-#include <linux/spinlock.h>
-#include <linux/sysrq.h>
-#include <linux/tty.h>
-#include <linux/tty_flip.h>
-#include <asm/hvcall.h>
-#include <asm/hvconsole.h>
-#include <asm/prom.h>
-#include <asm/uaccess.h>
-#include <asm/vio.h>
-#include <asm/param.h>
-
-#define HVSI_MAJOR     229
-#define HVSI_MINOR     128
-#define MAX_NR_HVSI_CONSOLES 4
-
-#define HVSI_TIMEOUT (5*HZ)
-#define HVSI_VERSION 1
-#define HVSI_MAX_PACKET 256
-#define HVSI_MAX_READ 16
-#define HVSI_MAX_OUTGOING_DATA 12
-#define N_OUTBUF 12
-
-/*
- * we pass data via two 8-byte registers, so we would like our char arrays
- * properly aligned for those loads.
- */
-#define __ALIGNED__    __attribute__((__aligned__(sizeof(long))))
-
-struct hvsi_struct {
-       struct delayed_work writer;
-       struct work_struct handshaker;
-       wait_queue_head_t emptyq; /* woken when outbuf is emptied */
-       wait_queue_head_t stateq; /* woken when HVSI state changes */
-       spinlock_t lock;
-       int index;
-       struct tty_struct *tty;
-       int count;
-       uint8_t throttle_buf[128];
-       uint8_t outbuf[N_OUTBUF]; /* to implement write_room and chars_in_buffer */
-       /* inbuf is for packet reassembly. leave a little room for leftovers. */
-       uint8_t inbuf[HVSI_MAX_PACKET + HVSI_MAX_READ];
-       uint8_t *inbuf_end;
-       int n_throttle;
-       int n_outbuf;
-       uint32_t vtermno;
-       uint32_t virq;
-       atomic_t seqno; /* HVSI packet sequence number */
-       uint16_t mctrl;
-       uint8_t state;  /* HVSI protocol state */
-       uint8_t flags;
-#ifdef CONFIG_MAGIC_SYSRQ
-       uint8_t sysrq;
-#endif /* CONFIG_MAGIC_SYSRQ */
-};
-static struct hvsi_struct hvsi_ports[MAX_NR_HVSI_CONSOLES];
-
-static struct tty_driver *hvsi_driver;
-static int hvsi_count;
-static int (*hvsi_wait)(struct hvsi_struct *hp, int state);
-
-enum HVSI_PROTOCOL_STATE {
-       HVSI_CLOSED,
-       HVSI_WAIT_FOR_VER_RESPONSE,
-       HVSI_WAIT_FOR_VER_QUERY,
-       HVSI_OPEN,
-       HVSI_WAIT_FOR_MCTRL_RESPONSE,
-       HVSI_FSP_DIED,
-};
-#define HVSI_CONSOLE 0x1
-
-#define VS_DATA_PACKET_HEADER           0xff
-#define VS_CONTROL_PACKET_HEADER        0xfe
-#define VS_QUERY_PACKET_HEADER          0xfd
-#define VS_QUERY_RESPONSE_PACKET_HEADER 0xfc
-
-/* control verbs */
-#define VSV_SET_MODEM_CTL    1 /* to service processor only */
-#define VSV_MODEM_CTL_UPDATE 2 /* from service processor only */
-#define VSV_CLOSE_PROTOCOL   3
-
-/* query verbs */
-#define VSV_SEND_VERSION_NUMBER 1
-#define VSV_SEND_MODEM_CTL_STATUS 2
-
-/* yes, these masks are not consecutive. */
-#define HVSI_TSDTR 0x01
-#define HVSI_TSCD  0x20
-
-struct hvsi_header {
-       uint8_t  type;
-       uint8_t  len;
-       uint16_t seqno;
-} __attribute__((packed));
-
-struct hvsi_data {
-       uint8_t  type;
-       uint8_t  len;
-       uint16_t seqno;
-       uint8_t  data[HVSI_MAX_OUTGOING_DATA];
-} __attribute__((packed));
-
-struct hvsi_control {
-       uint8_t  type;
-       uint8_t  len;
-       uint16_t seqno;
-       uint16_t verb;
-       /* optional depending on verb: */
-       uint32_t word;
-       uint32_t mask;
-} __attribute__((packed));
-
-struct hvsi_query {
-       uint8_t  type;
-       uint8_t  len;
-       uint16_t seqno;
-       uint16_t verb;
-} __attribute__((packed));
-
-struct hvsi_query_response {
-       uint8_t  type;
-       uint8_t  len;
-       uint16_t seqno;
-       uint16_t verb;
-       uint16_t query_seqno;
-       union {
-               uint8_t  version;
-               uint32_t mctrl_word;
-       } u;
-} __attribute__((packed));
-
-
-
-static inline int is_console(struct hvsi_struct *hp)
-{
-       return hp->flags & HVSI_CONSOLE;
-}
-
-static inline int is_open(struct hvsi_struct *hp)
-{
-       /* if we're waiting for an mctrl then we're already open */
-       return (hp->state == HVSI_OPEN)
-                       || (hp->state == HVSI_WAIT_FOR_MCTRL_RESPONSE);
-}
-
-static inline void print_state(struct hvsi_struct *hp)
-{
-#ifdef DEBUG
-       static const char *state_names[] = {
-               "HVSI_CLOSED",
-               "HVSI_WAIT_FOR_VER_RESPONSE",
-               "HVSI_WAIT_FOR_VER_QUERY",
-               "HVSI_OPEN",
-               "HVSI_WAIT_FOR_MCTRL_RESPONSE",
-               "HVSI_FSP_DIED",
-       };
-       const char *name = (hp->state < ARRAY_SIZE(state_names))
-               ? state_names[hp->state] : "UNKNOWN";
-
-       pr_debug("hvsi%i: state = %s\n", hp->index, name);
-#endif /* DEBUG */
-}
-
-static inline void __set_state(struct hvsi_struct *hp, int state)
-{
-       hp->state = state;
-       print_state(hp);
-       wake_up_all(&hp->stateq);
-}
-
-static inline void set_state(struct hvsi_struct *hp, int state)
-{
-       unsigned long flags;
-
-       spin_lock_irqsave(&hp->lock, flags);
-       __set_state(hp, state);
-       spin_unlock_irqrestore(&hp->lock, flags);
-}
-
-static inline int len_packet(const uint8_t *packet)
-{
-       return (int)((struct hvsi_header *)packet)->len;
-}
-
-static inline int is_header(const uint8_t *packet)
-{
-       struct hvsi_header *header = (struct hvsi_header *)packet;
-       return header->type >= VS_QUERY_RESPONSE_PACKET_HEADER;
-}
-
-static inline int got_packet(const struct hvsi_struct *hp, uint8_t *packet)
-{
-       if (hp->inbuf_end < packet + sizeof(struct hvsi_header))
-               return 0; /* don't even have the packet header */
-
-       if (hp->inbuf_end < (packet + len_packet(packet)))
-               return 0; /* don't have the rest of the packet */
-
-       return 1;
-}
-
-/* shift remaining bytes in packetbuf down */
-static void compact_inbuf(struct hvsi_struct *hp, uint8_t *read_to)
-{
-       int remaining = (int)(hp->inbuf_end - read_to);
-
-       pr_debug("%s: %i chars remain\n", __func__, remaining);
-
-       if (read_to != hp->inbuf)
-               memmove(hp->inbuf, read_to, remaining);
-
-       hp->inbuf_end = hp->inbuf + remaining;
-}
-
-#ifdef DEBUG
-#define dbg_dump_packet(packet) dump_packet(packet)
-#define dbg_dump_hex(data, len) dump_hex(data, len)
-#else
-#define dbg_dump_packet(packet) do { } while (0)
-#define dbg_dump_hex(data, len) do { } while (0)
-#endif
-
-static void dump_hex(const uint8_t *data, int len)
-{
-       int i;
-
-       printk("    ");
-       for (i=0; i < len; i++)
-               printk("%.2x", data[i]);
-
-       printk("\n    ");
-       for (i=0; i < len; i++) {
-               if (isprint(data[i]))
-                       printk("%c", data[i]);
-               else
-                       printk(".");
-       }
-       printk("\n");
-}
-
-static void dump_packet(uint8_t *packet)
-{
-       struct hvsi_header *header = (struct hvsi_header *)packet;
-
-       printk("type 0x%x, len %i, seqno %i:\n", header->type, header->len,
-                       header->seqno);
-
-       dump_hex(packet, header->len);
-}
-
-static int hvsi_read(struct hvsi_struct *hp, char *buf, int count)
-{
-       unsigned long got;
-
-       got = hvc_get_chars(hp->vtermno, buf, count);
-
-       return got;
-}
-
-static void hvsi_recv_control(struct hvsi_struct *hp, uint8_t *packet,
-       struct tty_struct **to_hangup, struct hvsi_struct **to_handshake)
-{
-       struct hvsi_control *header = (struct hvsi_control *)packet;
-
-       switch (header->verb) {
-               case VSV_MODEM_CTL_UPDATE:
-                       if ((header->word & HVSI_TSCD) == 0) {
-                               /* CD went away; no more connection */
-                               pr_debug("hvsi%i: CD dropped\n", hp->index);
-                               hp->mctrl &= TIOCM_CD;
-                               /* If userland hasn't done an open(2) yet, hp->tty is NULL. */
-                               if (hp->tty && !(hp->tty->flags & CLOCAL))
-                                       *to_hangup = hp->tty;
-                       }
-                       break;
-               case VSV_CLOSE_PROTOCOL:
-                       pr_debug("hvsi%i: service processor came back\n", hp->index);
-                       if (hp->state != HVSI_CLOSED) {
-                               *to_handshake = hp;
-                       }
-                       break;
-               default:
-                       printk(KERN_WARNING "hvsi%i: unknown HVSI control packet: ",
-                               hp->index);
-                       dump_packet(packet);
-                       break;
-       }
-}
-
-static void hvsi_recv_response(struct hvsi_struct *hp, uint8_t *packet)
-{
-       struct hvsi_query_response *resp = (struct hvsi_query_response *)packet;
-
-       switch (hp->state) {
-               case HVSI_WAIT_FOR_VER_RESPONSE:
-                       __set_state(hp, HVSI_WAIT_FOR_VER_QUERY);
-                       break;
-               case HVSI_WAIT_FOR_MCTRL_RESPONSE:
-                       hp->mctrl = 0;
-                       if (resp->u.mctrl_word & HVSI_TSDTR)
-                               hp->mctrl |= TIOCM_DTR;
-                       if (resp->u.mctrl_word & HVSI_TSCD)
-                               hp->mctrl |= TIOCM_CD;
-                       __set_state(hp, HVSI_OPEN);
-                       break;
-               default:
-                       printk(KERN_ERR "hvsi%i: unexpected query response: ", hp->index);
-                       dump_packet(packet);
-                       break;
-       }
-}
-
-/* respond to service processor's version query */
-static int hvsi_version_respond(struct hvsi_struct *hp, uint16_t query_seqno)
-{
-       struct hvsi_query_response packet __ALIGNED__;
-       int wrote;
-
-       packet.type = VS_QUERY_RESPONSE_PACKET_HEADER;
-       packet.len = sizeof(struct hvsi_query_response);
-       packet.seqno = atomic_inc_return(&hp->seqno);
-       packet.verb = VSV_SEND_VERSION_NUMBER;
-       packet.u.version = HVSI_VERSION;
-       packet.query_seqno = query_seqno+1;
-
-       pr_debug("%s: sending %i bytes\n", __func__, packet.len);
-       dbg_dump_hex((uint8_t*)&packet, packet.len);
-
-       wrote = hvc_put_chars(hp->vtermno, (char *)&packet, packet.len);
-       if (wrote != packet.len) {
-               printk(KERN_ERR "hvsi%i: couldn't send query response!\n",
-                       hp->index);
-               return -EIO;
-       }
-
-       return 0;
-}
-
-static void hvsi_recv_query(struct hvsi_struct *hp, uint8_t *packet)
-{
-       struct hvsi_query *query = (struct hvsi_query *)packet;
-
-       switch (hp->state) {
-               case HVSI_WAIT_FOR_VER_QUERY:
-                       hvsi_version_respond(hp, query->seqno);
-                       __set_state(hp, HVSI_OPEN);
-                       break;
-               default:
-                       printk(KERN_ERR "hvsi%i: unexpected query: ", hp->index);
-                       dump_packet(packet);
-                       break;
-       }
-}
-
-static void hvsi_insert_chars(struct hvsi_struct *hp, const char *buf, int len)
-{
-       int i;
-
-       for (i=0; i < len; i++) {
-               char c = buf[i];
-#ifdef CONFIG_MAGIC_SYSRQ
-               if (c == '\0') {
-                       hp->sysrq = 1;
-                       continue;
-               } else if (hp->sysrq) {
-                       handle_sysrq(c);
-                       hp->sysrq = 0;
-                       continue;
-               }
-#endif /* CONFIG_MAGIC_SYSRQ */
-               tty_insert_flip_char(hp->tty, c, 0);
-       }
-}
-
-/*
- * We could get 252 bytes of data at once here. But the tty layer only
- * throttles us at TTY_THRESHOLD_THROTTLE (128) bytes, so we could overflow
- * it. Accordingly we won't send more than 128 bytes at a time to the flip
- * buffer, which will give the tty buffer a chance to throttle us. Should the
- * value of TTY_THRESHOLD_THROTTLE change in n_tty.c, this code should be
- * revisited.
- */
-#define TTY_THRESHOLD_THROTTLE 128
-static struct tty_struct *hvsi_recv_data(struct hvsi_struct *hp,
-               const uint8_t *packet)
-{
-       const struct hvsi_header *header = (const struct hvsi_header *)packet;
-       const uint8_t *data = packet + sizeof(struct hvsi_header);
-       int datalen = header->len - sizeof(struct hvsi_header);
-       int overflow = datalen - TTY_THRESHOLD_THROTTLE;
-
-       pr_debug("queueing %i chars '%.*s'\n", datalen, datalen, data);
-
-       if (datalen == 0)
-               return NULL;
-
-       if (overflow > 0) {
-               pr_debug("%s: got >TTY_THRESHOLD_THROTTLE bytes\n", __func__);
-               datalen = TTY_THRESHOLD_THROTTLE;
-       }
-
-       hvsi_insert_chars(hp, data, datalen);
-
-       if (overflow > 0) {
-               /*
-                * we still have more data to deliver, so we need to save off the
-                * overflow and send it later
-                */
-               pr_debug("%s: deferring overflow\n", __func__);
-               memcpy(hp->throttle_buf, data + TTY_THRESHOLD_THROTTLE, overflow);
-               hp->n_throttle = overflow;
-       }
-
-       return hp->tty;
-}
-
-/*
- * Returns true/false indicating data successfully read from hypervisor.
- * Used both to get packets for tty connections and to advance the state
- * machine during console handshaking (in which case tty = NULL and we ignore
- * incoming data).
- */
-static int hvsi_load_chunk(struct hvsi_struct *hp, struct tty_struct **flip,
-               struct tty_struct **hangup, struct hvsi_struct **handshake)
-{
-       uint8_t *packet = hp->inbuf;
-       int chunklen;
-
-       *flip = NULL;
-       *hangup = NULL;
-       *handshake = NULL;
-
-       chunklen = hvsi_read(hp, hp->inbuf_end, HVSI_MAX_READ);
-       if (chunklen == 0) {
-               pr_debug("%s: 0-length read\n", __func__);
-               return 0;
-       }
-
-       pr_debug("%s: got %i bytes\n", __func__, chunklen);
-       dbg_dump_hex(hp->inbuf_end, chunklen);
-
-       hp->inbuf_end += chunklen;
-
-       /* handle all completed packets */
-       while ((packet < hp->inbuf_end) && got_packet(hp, packet)) {
-               struct hvsi_header *header = (struct hvsi_header *)packet;
-
-               if (!is_header(packet)) {
-                       printk(KERN_ERR "hvsi%i: got malformed packet\n", hp->index);
-                       /* skip bytes until we find a header or run out of data */
-                       while ((packet < hp->inbuf_end) && (!is_header(packet)))
-                               packet++;
-                       continue;
-               }
-
-               pr_debug("%s: handling %i-byte packet\n", __func__,
-                               len_packet(packet));
-               dbg_dump_packet(packet);
-
-               switch (header->type) {
-                       case VS_DATA_PACKET_HEADER:
-                               if (!is_open(hp))
-                                       break;
-                               if (hp->tty == NULL)
-                                       break; /* no tty buffer to put data in */
-                               *flip = hvsi_recv_data(hp, packet);
-                               break;
-                       case VS_CONTROL_PACKET_HEADER:
-                               hvsi_recv_control(hp, packet, hangup, handshake);
-                               break;
-                       case VS_QUERY_RESPONSE_PACKET_HEADER:
-                               hvsi_recv_response(hp, packet);
-                               break;
-                       case VS_QUERY_PACKET_HEADER:
-                               hvsi_recv_query(hp, packet);
-                               break;
-                       default:
-                               printk(KERN_ERR "hvsi%i: unknown HVSI packet type 0x%x\n",
-                                               hp->index, header->type);
-                               dump_packet(packet);
-                               break;
-               }
-
-               packet += len_packet(packet);
-
-               if (*hangup || *handshake) {
-                       pr_debug("%s: hangup or handshake\n", __func__);
-                       /*
-                        * we need to send the hangup now before receiving any more data.
-                        * If we get "data, hangup, data", we can't deliver the second
-                        * data before the hangup.
-                        */
-                       break;
-               }
-       }
-
-       compact_inbuf(hp, packet);
-
-       return 1;
-}
-
-static void hvsi_send_overflow(struct hvsi_struct *hp)
-{
-       pr_debug("%s: delivering %i bytes overflow\n", __func__,
-                       hp->n_throttle);
-
-       hvsi_insert_chars(hp, hp->throttle_buf, hp->n_throttle);
-       hp->n_throttle = 0;
-}
-
-/*
- * must get all pending data because we only get an irq on empty->non-empty
- * transition
- */
-static irqreturn_t hvsi_interrupt(int irq, void *arg)
-{
-       struct hvsi_struct *hp = (struct hvsi_struct *)arg;
-       struct tty_struct *flip;
-       struct tty_struct *hangup;
-       struct hvsi_struct *handshake;
-       unsigned long flags;
-       int again = 1;
-
-       pr_debug("%s\n", __func__);
-
-       while (again) {
-               spin_lock_irqsave(&hp->lock, flags);
-               again = hvsi_load_chunk(hp, &flip, &hangup, &handshake);
-               spin_unlock_irqrestore(&hp->lock, flags);
-
-               /*
-                * we have to call tty_flip_buffer_push() and tty_hangup() outside our
-                * spinlock. But we also have to keep going until we've read all the
-                * available data.
-                */
-
-               if (flip) {
-                       /* there was data put in the tty flip buffer */
-                       tty_flip_buffer_push(flip);
-                       flip = NULL;
-               }
-
-               if (hangup) {
-                       tty_hangup(hangup);
-               }
-
-               if (handshake) {
-                       pr_debug("hvsi%i: attempting re-handshake\n", handshake->index);
-                       schedule_work(&handshake->handshaker);
-               }
-       }
-
-       spin_lock_irqsave(&hp->lock, flags);
-       if (hp->tty && hp->n_throttle
-                       && (!test_bit(TTY_THROTTLED, &hp->tty->flags))) {
-               /* we weren't hung up and we weren't throttled, so we can deliver the
-                * rest now */
-               flip = hp->tty;
-               hvsi_send_overflow(hp);
-       }
-       spin_unlock_irqrestore(&hp->lock, flags);
-
-       if (flip) {
-               tty_flip_buffer_push(flip);
-       }
-
-       return IRQ_HANDLED;
-}
-
-/* for boot console, before the irq handler is running */
-static int __init poll_for_state(struct hvsi_struct *hp, int state)
-{
-       unsigned long end_jiffies = jiffies + HVSI_TIMEOUT;
-
-       for (;;) {
-               hvsi_interrupt(hp->virq, (void *)hp); /* get pending data */
-
-               if (hp->state == state)
-                       return 0;
-
-               mdelay(5);
-               if (time_after(jiffies, end_jiffies))
-                       return -EIO;
-       }
-}
-
-/* wait for irq handler to change our state */
-static int wait_for_state(struct hvsi_struct *hp, int state)
-{
-       int ret = 0;
-
-       if (!wait_event_timeout(hp->stateq, (hp->state == state), HVSI_TIMEOUT))
-               ret = -EIO;
-
-       return ret;
-}
-
-static int hvsi_query(struct hvsi_struct *hp, uint16_t verb)
-{
-       struct hvsi_query packet __ALIGNED__;
-       int wrote;
-
-       packet.type = VS_QUERY_PACKET_HEADER;
-       packet.len = sizeof(struct hvsi_query);
-       packet.seqno = atomic_inc_return(&hp->seqno);
-       packet.verb = verb;
-
-       pr_debug("%s: sending %i bytes\n", __func__, packet.len);
-       dbg_dump_hex((uint8_t*)&packet, packet.len);
-
-       wrote = hvc_put_chars(hp->vtermno, (char *)&packet, packet.len);
-       if (wrote != packet.len) {
-               printk(KERN_ERR "hvsi%i: couldn't send query (%i)!\n", hp->index,
-                       wrote);
-               return -EIO;
-       }
-
-       return 0;
-}
-
-static int hvsi_get_mctrl(struct hvsi_struct *hp)
-{
-       int ret;
-
-       set_state(hp, HVSI_WAIT_FOR_MCTRL_RESPONSE);
-       hvsi_query(hp, VSV_SEND_MODEM_CTL_STATUS);
-
-       ret = hvsi_wait(hp, HVSI_OPEN);
-       if (ret < 0) {
-               printk(KERN_ERR "hvsi%i: didn't get modem flags\n", hp->index);
-               set_state(hp, HVSI_OPEN);
-               return ret;
-       }
-
-       pr_debug("%s: mctrl 0x%x\n", __func__, hp->mctrl);
-
-       return 0;
-}
-
-/* note that we can only set DTR */
-static int hvsi_set_mctrl(struct hvsi_struct *hp, uint16_t mctrl)
-{
-       struct hvsi_control packet __ALIGNED__;
-       int wrote;
-
-       packet.type = VS_CONTROL_PACKET_HEADER,
-       packet.seqno = atomic_inc_return(&hp->seqno);
-       packet.len = sizeof(struct hvsi_control);
-       packet.verb = VSV_SET_MODEM_CTL;
-       packet.mask = HVSI_TSDTR;
-
-       if (mctrl & TIOCM_DTR)
-               packet.word = HVSI_TSDTR;
-
-       pr_debug("%s: sending %i bytes\n", __func__, packet.len);
-       dbg_dump_hex((uint8_t*)&packet, packet.len);
-
-       wrote = hvc_put_chars(hp->vtermno, (char *)&packet, packet.len);
-       if (wrote != packet.len) {
-               printk(KERN_ERR "hvsi%i: couldn't set DTR!\n", hp->index);
-               return -EIO;
-       }
-
-       return 0;
-}
-
-static void hvsi_drain_input(struct hvsi_struct *hp)
-{
-       uint8_t buf[HVSI_MAX_READ] __ALIGNED__;
-       unsigned long end_jiffies = jiffies + HVSI_TIMEOUT;
-
-       while (time_before(end_jiffies, jiffies))
-               if (0 == hvsi_read(hp, buf, HVSI_MAX_READ))
-                       break;
-}
-
-static int hvsi_handshake(struct hvsi_struct *hp)
-{
-       int ret;
-
-       /*
-        * We could have a CLOSE or other data waiting for us before we even try
-        * to open; try to throw it all away so we don't get confused. (CLOSE
-        * is the first message sent up the pipe when the FSP comes online. We
-        * need to distinguish between "it came up a while ago and we're the first
-        * user" and "it was just reset before it saw our handshake packet".)
-        */
-       hvsi_drain_input(hp);
-
-       set_state(hp, HVSI_WAIT_FOR_VER_RESPONSE);
-       ret = hvsi_query(hp, VSV_SEND_VERSION_NUMBER);
-       if (ret < 0) {
-               printk(KERN_ERR "hvsi%i: couldn't send version query\n", hp->index);
-               return ret;
-       }
-
-       ret = hvsi_wait(hp, HVSI_OPEN);
-       if (ret < 0)
-               return ret;
-
-       return 0;
-}
-
-static void hvsi_handshaker(struct work_struct *work)
-{
-       struct hvsi_struct *hp =
-               container_of(work, struct hvsi_struct, handshaker);
-
-       if (hvsi_handshake(hp) >= 0)
-               return;
-
-       printk(KERN_ERR "hvsi%i: re-handshaking failed\n", hp->index);
-       if (is_console(hp)) {
-               /*
-                * ttys will re-attempt the handshake via hvsi_open, but
-                * the console will not.
-                */
-               printk(KERN_ERR "hvsi%i: lost console!\n", hp->index);
-       }
-}
-
-static int hvsi_put_chars(struct hvsi_struct *hp, const char *buf, int count)
-{
-       struct hvsi_data packet __ALIGNED__;
-       int ret;
-
-       BUG_ON(count > HVSI_MAX_OUTGOING_DATA);
-
-       packet.type = VS_DATA_PACKET_HEADER;
-       packet.seqno = atomic_inc_return(&hp->seqno);
-       packet.len = count + sizeof(struct hvsi_header);
-       memcpy(&packet.data, buf, count);
-
-       ret = hvc_put_chars(hp->vtermno, (char *)&packet, packet.len);
-       if (ret == packet.len) {
-               /* return the number of chars written, not the packet length */
-               return count;
-       }
-       return ret; /* return any errors */
-}
-
-static void hvsi_close_protocol(struct hvsi_struct *hp)
-{
-       struct hvsi_control packet __ALIGNED__;
-
-       packet.type = VS_CONTROL_PACKET_HEADER;
-       packet.seqno = atomic_inc_return(&hp->seqno);
-       packet.len = 6;
-       packet.verb = VSV_CLOSE_PROTOCOL;
-
-       pr_debug("%s: sending %i bytes\n", __func__, packet.len);
-       dbg_dump_hex((uint8_t*)&packet, packet.len);
-
-       hvc_put_chars(hp->vtermno, (char *)&packet, packet.len);
-}
-
-static int hvsi_open(struct tty_struct *tty, struct file *filp)
-{
-       struct hvsi_struct *hp;
-       unsigned long flags;
-       int line = tty->index;
-       int ret;
-
-       pr_debug("%s\n", __func__);
-
-       if (line < 0 || line >= hvsi_count)
-               return -ENODEV;
-       hp = &hvsi_ports[line];
-
-       tty->driver_data = hp;
-
-       mb();
-       if (hp->state == HVSI_FSP_DIED)
-               return -EIO;
-
-       spin_lock_irqsave(&hp->lock, flags);
-       hp->tty = tty;
-       hp->count++;
-       atomic_set(&hp->seqno, 0);
-       h_vio_signal(hp->vtermno, VIO_IRQ_ENABLE);
-       spin_unlock_irqrestore(&hp->lock, flags);
-
-       if (is_console(hp))
-               return 0; /* this has already been handshaked as the console */
-
-       ret = hvsi_handshake(hp);
-       if (ret < 0) {
-               printk(KERN_ERR "%s: HVSI handshaking failed\n", tty->name);
-               return ret;
-       }
-
-       ret = hvsi_get_mctrl(hp);
-       if (ret < 0) {
-               printk(KERN_ERR "%s: couldn't get initial modem flags\n", tty->name);
-               return ret;
-       }
-
-       ret = hvsi_set_mctrl(hp, hp->mctrl | TIOCM_DTR);
-       if (ret < 0) {
-               printk(KERN_ERR "%s: couldn't set DTR\n", tty->name);
-               return ret;
-       }
-
-       return 0;
-}
-
-/* wait for hvsi_write_worker to empty hp->outbuf */
-static void hvsi_flush_output(struct hvsi_struct *hp)
-{
-       wait_event_timeout(hp->emptyq, (hp->n_outbuf <= 0), HVSI_TIMEOUT);
-
-       /* 'writer' could still be pending if it didn't see n_outbuf = 0 yet */
-       cancel_delayed_work_sync(&hp->writer);
-       flush_work_sync(&hp->handshaker);
-
-       /*
-        * it's also possible that our timeout expired and hvsi_write_worker
-        * didn't manage to push outbuf. poof.
-        */
-       hp->n_outbuf = 0;
-}
-
-static void hvsi_close(struct tty_struct *tty, struct file *filp)
-{
-       struct hvsi_struct *hp = tty->driver_data;
-       unsigned long flags;
-
-       pr_debug("%s\n", __func__);
-
-       if (tty_hung_up_p(filp))
-               return;
-
-       spin_lock_irqsave(&hp->lock, flags);
-
-       if (--hp->count == 0) {
-               hp->tty = NULL;
-               hp->inbuf_end = hp->inbuf; /* discard remaining partial packets */
-
-               /* only close down connection if it is not the console */
-               if (!is_console(hp)) {
-                       h_vio_signal(hp->vtermno, VIO_IRQ_DISABLE); /* no more irqs */
-                       __set_state(hp, HVSI_CLOSED);
-                       /*
-                        * any data delivered to the tty layer after this will be
-                        * discarded (except for XON/XOFF)
-                        */
-                       tty->closing = 1;
-
-                       spin_unlock_irqrestore(&hp->lock, flags);
-
-                       /* let any existing irq handlers finish. no more will start. */
-                       synchronize_irq(hp->virq);
-
-                       /* hvsi_write_worker will re-schedule until outbuf is empty. */
-                       hvsi_flush_output(hp);
-
-                       /* tell FSP to stop sending data */
-                       hvsi_close_protocol(hp);
-
-                       /*
-                        * drain anything FSP is still in the middle of sending, and let
-                        * hvsi_handshake drain the rest on the next open.
-                        */
-                       hvsi_drain_input(hp);
-
-                       spin_lock_irqsave(&hp->lock, flags);
-               }
-       } else if (hp->count < 0)
-               printk(KERN_ERR "hvsi_close %lu: oops, count is %d\n",
-                      hp - hvsi_ports, hp->count);
-
-       spin_unlock_irqrestore(&hp->lock, flags);
-}
-
-static void hvsi_hangup(struct tty_struct *tty)
-{
-       struct hvsi_struct *hp = tty->driver_data;
-       unsigned long flags;
-
-       pr_debug("%s\n", __func__);
-
-       spin_lock_irqsave(&hp->lock, flags);
-
-       hp->count = 0;
-       hp->n_outbuf = 0;
-       hp->tty = NULL;
-
-       spin_unlock_irqrestore(&hp->lock, flags);
-}
-
-/* called with hp->lock held */
-static void hvsi_push(struct hvsi_struct *hp)
-{
-       int n;
-
-       if (hp->n_outbuf <= 0)
-               return;
-
-       n = hvsi_put_chars(hp, hp->outbuf, hp->n_outbuf);
-       if (n > 0) {
-               /* success */
-               pr_debug("%s: wrote %i chars\n", __func__, n);
-               hp->n_outbuf = 0;
-       } else if (n == -EIO) {
-               __set_state(hp, HVSI_FSP_DIED);
-               printk(KERN_ERR "hvsi%i: service processor died\n", hp->index);
-       }
-}
-
-/* hvsi_write_worker will keep rescheduling itself until outbuf is empty */
-static void hvsi_write_worker(struct work_struct *work)
-{
-       struct hvsi_struct *hp =
-               container_of(work, struct hvsi_struct, writer.work);
-       unsigned long flags;
-#ifdef DEBUG
-       static long start_j = 0;
-
-       if (start_j == 0)
-               start_j = jiffies;
-#endif /* DEBUG */
-
-       spin_lock_irqsave(&hp->lock, flags);
-
-       pr_debug("%s: %i chars in buffer\n", __func__, hp->n_outbuf);
-
-       if (!is_open(hp)) {
-               /*
-                * We could have a non-open connection if the service processor died
-                * while we were busily scheduling ourselves. In that case, it could
-                * be minutes before the service processor comes back, so only try
-                * again once a second.
-                */
-               schedule_delayed_work(&hp->writer, HZ);
-               goto out;
-       }
-
-       hvsi_push(hp);
-       if (hp->n_outbuf > 0)
-               schedule_delayed_work(&hp->writer, 10);
-       else {
-#ifdef DEBUG
-               pr_debug("%s: outbuf emptied after %li jiffies\n", __func__,
-                               jiffies - start_j);
-               start_j = 0;
-#endif /* DEBUG */
-               wake_up_all(&hp->emptyq);
-               tty_wakeup(hp->tty);
-       }
-
-out:
-       spin_unlock_irqrestore(&hp->lock, flags);
-}
-
-static int hvsi_write_room(struct tty_struct *tty)
-{
-       struct hvsi_struct *hp = tty->driver_data;
-
-       return N_OUTBUF - hp->n_outbuf;
-}
-
-static int hvsi_chars_in_buffer(struct tty_struct *tty)
-{
-       struct hvsi_struct *hp = tty->driver_data;
-
-       return hp->n_outbuf;
-}
-
-static int hvsi_write(struct tty_struct *tty,
-                    const unsigned char *buf, int count)
-{
-       struct hvsi_struct *hp = tty->driver_data;
-       const char *source = buf;
-       unsigned long flags;
-       int total = 0;
-       int origcount = count;
-
-       spin_lock_irqsave(&hp->lock, flags);
-
-       pr_debug("%s: %i chars in buffer\n", __func__, hp->n_outbuf);
-
-       if (!is_open(hp)) {
-               /* we're either closing or not yet open; don't accept data */
-               pr_debug("%s: not open\n", __func__);
-               goto out;
-       }
-
-       /*
-        * when the hypervisor buffer (16K) fills, data will stay in hp->outbuf
-        * and hvsi_write_worker will be scheduled. subsequent hvsi_write() calls
-        * will see there is no room in outbuf and return.
-        */
-       while ((count > 0) && (hvsi_write_room(hp->tty) > 0)) {
-               int chunksize = min(count, hvsi_write_room(hp->tty));
-
-               BUG_ON(hp->n_outbuf < 0);
-               memcpy(hp->outbuf + hp->n_outbuf, source, chunksize);
-               hp->n_outbuf += chunksize;
-
-               total += chunksize;
-               source += chunksize;
-               count -= chunksize;
-               hvsi_push(hp);
-       }
-
-       if (hp->n_outbuf > 0) {
-               /*
-                * we weren't able to write it all to the hypervisor.
-                * schedule another push attempt.
-                */
-               schedule_delayed_work(&hp->writer, 10);
-       }
-
-out:
-       spin_unlock_irqrestore(&hp->lock, flags);
-
-       if (total != origcount)
-               pr_debug("%s: wanted %i, only wrote %i\n", __func__, origcount,
-                       total);
-
-       return total;
-}
-
-/*
- * I have never seen throttle or unthrottle called, so this little throttle
- * buffering scheme may or may not work.
- */
-static void hvsi_throttle(struct tty_struct *tty)
-{
-       struct hvsi_struct *hp = tty->driver_data;
-
-       pr_debug("%s\n", __func__);
-
-       h_vio_signal(hp->vtermno, VIO_IRQ_DISABLE);
-}
-
-static void hvsi_unthrottle(struct tty_struct *tty)
-{
-       struct hvsi_struct *hp = tty->driver_data;
-       unsigned long flags;
-       int shouldflip = 0;
-
-       pr_debug("%s\n", __func__);
-
-       spin_lock_irqsave(&hp->lock, flags);
-       if (hp->n_throttle) {
-               hvsi_send_overflow(hp);
-               shouldflip = 1;
-       }
-       spin_unlock_irqrestore(&hp->lock, flags);
-
-       if (shouldflip)
-               tty_flip_buffer_push(hp->tty);
-
-       h_vio_signal(hp->vtermno, VIO_IRQ_ENABLE);
-}
-
-static int hvsi_tiocmget(struct tty_struct *tty, struct file *file)
-{
-       struct hvsi_struct *hp = tty->driver_data;
-
-       hvsi_get_mctrl(hp);
-       return hp->mctrl;
-}
-
-static int hvsi_tiocmset(struct tty_struct *tty, struct file *file,
-               unsigned int set, unsigned int clear)
-{
-       struct hvsi_struct *hp = tty->driver_data;
-       unsigned long flags;
-       uint16_t new_mctrl;
-
-       /* we can only alter DTR */
-       clear &= TIOCM_DTR;
-       set &= TIOCM_DTR;
-
-       spin_lock_irqsave(&hp->lock, flags);
-
-       new_mctrl = (hp->mctrl & ~clear) | set;
-
-       if (hp->mctrl != new_mctrl) {
-               hvsi_set_mctrl(hp, new_mctrl);
-               hp->mctrl = new_mctrl;
-       }
-       spin_unlock_irqrestore(&hp->lock, flags);
-
-       return 0;
-}
-
-
-static const struct tty_operations hvsi_ops = {
-       .open = hvsi_open,
-       .close = hvsi_close,
-       .write = hvsi_write,
-       .hangup = hvsi_hangup,
-       .write_room = hvsi_write_room,
-       .chars_in_buffer = hvsi_chars_in_buffer,
-       .throttle = hvsi_throttle,
-       .unthrottle = hvsi_unthrottle,
-       .tiocmget = hvsi_tiocmget,
-       .tiocmset = hvsi_tiocmset,
-};
-
-static int __init hvsi_init(void)
-{
-       int i;
-
-       hvsi_driver = alloc_tty_driver(hvsi_count);
-       if (!hvsi_driver)
-               return -ENOMEM;
-
-       hvsi_driver->owner = THIS_MODULE;
-       hvsi_driver->driver_name = "hvsi";
-       hvsi_driver->name = "hvsi";
-       hvsi_driver->major = HVSI_MAJOR;
-       hvsi_driver->minor_start = HVSI_MINOR;
-       hvsi_driver->type = TTY_DRIVER_TYPE_SYSTEM;
-       hvsi_driver->init_termios = tty_std_termios;
-       hvsi_driver->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL;
-       hvsi_driver->init_termios.c_ispeed = 9600;
-       hvsi_driver->init_termios.c_ospeed = 9600;
-       hvsi_driver->flags = TTY_DRIVER_REAL_RAW;
-       tty_set_operations(hvsi_driver, &hvsi_ops);
-
-       for (i=0; i < hvsi_count; i++) {
-               struct hvsi_struct *hp = &hvsi_ports[i];
-               int ret = 1;
-
-               ret = request_irq(hp->virq, hvsi_interrupt, IRQF_DISABLED, "hvsi", hp);
-               if (ret)
-                       printk(KERN_ERR "HVSI: couldn't reserve irq 0x%x (error %i)\n",
-                               hp->virq, ret);
-       }
-       hvsi_wait = wait_for_state; /* irqs active now */
-
-       if (tty_register_driver(hvsi_driver))
-               panic("Couldn't register hvsi console driver\n");
-
-       printk(KERN_DEBUG "HVSI: registered %i devices\n", hvsi_count);
-
-       return 0;
-}
-device_initcall(hvsi_init);
-
-/***** console (not tty) code: *****/
-
-static void hvsi_console_print(struct console *console, const char *buf,
-               unsigned int count)
-{
-       struct hvsi_struct *hp = &hvsi_ports[console->index];
-       char c[HVSI_MAX_OUTGOING_DATA] __ALIGNED__;
-       unsigned int i = 0, n = 0;
-       int ret, donecr = 0;
-
-       mb();
-       if (!is_open(hp))
-               return;
-
-       /*
-        * ugh, we have to translate LF -> CRLF ourselves, in place.
-        * copied from hvc_console.c:
-        */
-       while (count > 0 || i > 0) {
-               if (count > 0 && i < sizeof(c)) {
-                       if (buf[n] == '\n' && !donecr) {
-                               c[i++] = '\r';
-                               donecr = 1;
-                       } else {
-                               c[i++] = buf[n++];
-                               donecr = 0;
-                               --count;
-                       }
-               } else {
-                       ret = hvsi_put_chars(hp, c, i);
-                       if (ret < 0)
-                               i = 0;
-                       i -= ret;
-               }
-       }
-}
-
-static struct tty_driver *hvsi_console_device(struct console *console,
-       int *index)
-{
-       *index = console->index;
-       return hvsi_driver;
-}
-
-static int __init hvsi_console_setup(struct console *console, char *options)
-{
-       struct hvsi_struct *hp;
-       int ret;
-
-       if (console->index < 0 || console->index >= hvsi_count)
-               return -1;
-       hp = &hvsi_ports[console->index];
-
-       /* give the FSP a chance to change the baud rate when we re-open */
-       hvsi_close_protocol(hp);
-
-       ret = hvsi_handshake(hp);
-       if (ret < 0)
-               return ret;
-
-       ret = hvsi_get_mctrl(hp);
-       if (ret < 0)
-               return ret;
-
-       ret = hvsi_set_mctrl(hp, hp->mctrl | TIOCM_DTR);
-       if (ret < 0)
-               return ret;
-
-       hp->flags |= HVSI_CONSOLE;
-
-       return 0;
-}
-
-static struct console hvsi_console = {
-       .name           = "hvsi",
-       .write          = hvsi_console_print,
-       .device         = hvsi_console_device,
-       .setup          = hvsi_console_setup,
-       .flags          = CON_PRINTBUFFER,
-       .index          = -1,
-};
-
-static int __init hvsi_console_init(void)
-{
-       struct device_node *vty;
-
-       hvsi_wait = poll_for_state; /* no irqs yet; must poll */
-
-       /* search device tree for vty nodes */
-       for (vty = of_find_compatible_node(NULL, "serial", "hvterm-protocol");
-                       vty != NULL;
-                       vty = of_find_compatible_node(vty, "serial", "hvterm-protocol")) {
-               struct hvsi_struct *hp;
-               const uint32_t *vtermno, *irq;
-
-               vtermno = of_get_property(vty, "reg", NULL);
-               irq = of_get_property(vty, "interrupts", NULL);
-               if (!vtermno || !irq)
-                       continue;
-
-               if (hvsi_count >= MAX_NR_HVSI_CONSOLES) {
-                       of_node_put(vty);
-                       break;
-               }
-
-               hp = &hvsi_ports[hvsi_count];
-               INIT_DELAYED_WORK(&hp->writer, hvsi_write_worker);
-               INIT_WORK(&hp->handshaker, hvsi_handshaker);
-               init_waitqueue_head(&hp->emptyq);
-               init_waitqueue_head(&hp->stateq);
-               spin_lock_init(&hp->lock);
-               hp->index = hvsi_count;
-               hp->inbuf_end = hp->inbuf;
-               hp->state = HVSI_CLOSED;
-               hp->vtermno = *vtermno;
-               hp->virq = irq_create_mapping(NULL, irq[0]);
-               if (hp->virq == NO_IRQ) {
-                       printk(KERN_ERR "%s: couldn't create irq mapping for 0x%x\n",
-                               __func__, irq[0]);
-                       continue;
-               }
-
-               hvsi_count++;
-       }
-
-       if (hvsi_count)
-               register_console(&hvsi_console);
-       return 0;
-}
-console_initcall(hvsi_console_init);
diff --git a/drivers/char/virtio_console.c b/drivers/char/virtio_console.c
deleted file mode 100644 (file)
index 896a2ce..0000000
+++ /dev/null
@@ -1,1838 +0,0 @@
-/*
- * Copyright (C) 2006, 2007, 2009 Rusty Russell, IBM Corporation
- * Copyright (C) 2009, 2010 Red Hat, Inc.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
- */
-#include <linux/cdev.h>
-#include <linux/debugfs.h>
-#include <linux/device.h>
-#include <linux/err.h>
-#include <linux/fs.h>
-#include <linux/init.h>
-#include <linux/list.h>
-#include <linux/poll.h>
-#include <linux/sched.h>
-#include <linux/slab.h>
-#include <linux/spinlock.h>
-#include <linux/virtio.h>
-#include <linux/virtio_console.h>
-#include <linux/wait.h>
-#include <linux/workqueue.h>
-#include "hvc_console.h"
-
-/*
- * This is a global struct for storing common data for all the devices
- * this driver handles.
- *
- * Mainly, it has a linked list for all the consoles in one place so
- * that callbacks from hvc for get_chars(), put_chars() work properly
- * across multiple devices and multiple ports per device.
- */
-struct ports_driver_data {
-       /* Used for registering chardevs */
-       struct class *class;
-
-       /* Used for exporting per-port information to debugfs */
-       struct dentry *debugfs_dir;
-
-       /* List of all the devices we're handling */
-       struct list_head portdevs;
-
-       /* Number of devices this driver is handling */
-       unsigned int index;
-
-       /*
-        * This is used to keep track of the number of hvc consoles
-        * spawned by this driver.  This number is given as the first
-        * argument to hvc_alloc().  To correctly map an initial
-        * console spawned via hvc_instantiate to the console being
-        * hooked up via hvc_alloc, we need to pass the same vtermno.
-        *
-        * We also just assume the first console being initialised was
-        * the first one that got used as the initial console.
-        */
-       unsigned int next_vtermno;
-
-       /* All the console devices handled by this driver */
-       struct list_head consoles;
-};
-static struct ports_driver_data pdrvdata;
-
-DEFINE_SPINLOCK(pdrvdata_lock);
-
-/* This struct holds information that's relevant only for console ports */
-struct console {
-       /* We'll place all consoles in a list in the pdrvdata struct */
-       struct list_head list;
-
-       /* The hvc device associated with this console port */
-       struct hvc_struct *hvc;
-
-       /* The size of the console */
-       struct winsize ws;
-
-       /*
-        * This number identifies the number that we used to register
-        * with hvc in hvc_instantiate() and hvc_alloc(); this is the
-        * number passed on by the hvc callbacks to us to
-        * differentiate between the other console ports handled by
-        * this driver
-        */
-       u32 vtermno;
-};
-
-struct port_buffer {
-       char *buf;
-
-       /* size of the buffer in *buf above */
-       size_t size;
-
-       /* used length of the buffer */
-       size_t len;
-       /* offset in the buf from which to consume data */
-       size_t offset;
-};
-
-/*
- * This is a per-device struct that stores data common to all the
- * ports for that device (vdev->priv).
- */
-struct ports_device {
-       /* Next portdev in the list, head is in the pdrvdata struct */
-       struct list_head list;
-
-       /*
-        * Workqueue handlers where we process deferred work after
-        * notification
-        */
-       struct work_struct control_work;
-
-       struct list_head ports;
-
-       /* To protect the list of ports */
-       spinlock_t ports_lock;
-
-       /* To protect the vq operations for the control channel */
-       spinlock_t cvq_lock;
-
-       /* The current config space is stored here */
-       struct virtio_console_config config;
-
-       /* The virtio device we're associated with */
-       struct virtio_device *vdev;
-
-       /*
-        * A couple of virtqueues for the control channel: one for
-        * guest->host transfers, one for host->guest transfers
-        */
-       struct virtqueue *c_ivq, *c_ovq;
-
-       /* Array of per-port IO virtqueues */
-       struct virtqueue **in_vqs, **out_vqs;
-
-       /* Used for numbering devices for sysfs and debugfs */
-       unsigned int drv_index;
-
-       /* Major number for this device.  Ports will be created as minors. */
-       int chr_major;
-};
-
-/* This struct holds the per-port data */
-struct port {
-       /* Next port in the list, head is in the ports_device */
-       struct list_head list;
-
-       /* Pointer to the parent virtio_console device */
-       struct ports_device *portdev;
-
-       /* The current buffer from which data has to be fed to readers */
-       struct port_buffer *inbuf;
-
-       /*
-        * To protect the operations on the in_vq associated with this
-        * port.  Has to be a spinlock because it can be called from
-        * interrupt context (get_char()).
-        */
-       spinlock_t inbuf_lock;
-
-       /* Protect the operations on the out_vq. */
-       spinlock_t outvq_lock;
-
-       /* The IO vqs for this port */
-       struct virtqueue *in_vq, *out_vq;
-
-       /* File in the debugfs directory that exposes this port's information */
-       struct dentry *debugfs_file;
-
-       /*
-        * The entries in this struct will be valid if this port is
-        * hooked up to an hvc console
-        */
-       struct console cons;
-
-       /* Each port associates with a separate char device */
-       struct cdev *cdev;
-       struct device *dev;
-
-       /* Reference-counting to handle port hot-unplugs and file operations */
-       struct kref kref;
-
-       /* A waitqueue for poll() or blocking read operations */
-       wait_queue_head_t waitqueue;
-
-       /* The 'name' of the port that we expose via sysfs properties */
-       char *name;
-
-       /* We can notify apps of host connect / disconnect events via SIGIO */
-       struct fasync_struct *async_queue;
-
-       /* The 'id' to identify the port with the Host */
-       u32 id;
-
-       bool outvq_full;
-
-       /* Is the host device open */
-       bool host_connected;
-
-       /* We should allow only one process to open a port */
-       bool guest_connected;
-};
-
-/* This is the very early arch-specified put chars function. */
-static int (*early_put_chars)(u32, const char *, int);
-
-static struct port *find_port_by_vtermno(u32 vtermno)
-{
-       struct port *port;
-       struct console *cons;
-       unsigned long flags;
-
-       spin_lock_irqsave(&pdrvdata_lock, flags);
-       list_for_each_entry(cons, &pdrvdata.consoles, list) {
-               if (cons->vtermno == vtermno) {
-                       port = container_of(cons, struct port, cons);
-                       goto out;
-               }
-       }
-       port = NULL;
-out:
-       spin_unlock_irqrestore(&pdrvdata_lock, flags);
-       return port;
-}
-
-static struct port *find_port_by_devt_in_portdev(struct ports_device *portdev,
-                                                dev_t dev)
-{
-       struct port *port;
-       unsigned long flags;
-
-       spin_lock_irqsave(&portdev->ports_lock, flags);
-       list_for_each_entry(port, &portdev->ports, list)
-               if (port->cdev->dev == dev)
-                       goto out;
-       port = NULL;
-out:
-       spin_unlock_irqrestore(&portdev->ports_lock, flags);
-
-       return port;
-}
-
-static struct port *find_port_by_devt(dev_t dev)
-{
-       struct ports_device *portdev;
-       struct port *port;
-       unsigned long flags;
-
-       spin_lock_irqsave(&pdrvdata_lock, flags);
-       list_for_each_entry(portdev, &pdrvdata.portdevs, list) {
-               port = find_port_by_devt_in_portdev(portdev, dev);
-               if (port)
-                       goto out;
-       }
-       port = NULL;
-out:
-       spin_unlock_irqrestore(&pdrvdata_lock, flags);
-       return port;
-}
-
-static struct port *find_port_by_id(struct ports_device *portdev, u32 id)
-{
-       struct port *port;
-       unsigned long flags;
-
-       spin_lock_irqsave(&portdev->ports_lock, flags);
-       list_for_each_entry(port, &portdev->ports, list)
-               if (port->id == id)
-                       goto out;
-       port = NULL;
-out:
-       spin_unlock_irqrestore(&portdev->ports_lock, flags);
-
-       return port;
-}
-
-static struct port *find_port_by_vq(struct ports_device *portdev,
-                                   struct virtqueue *vq)
-{
-       struct port *port;
-       unsigned long flags;
-
-       spin_lock_irqsave(&portdev->ports_lock, flags);
-       list_for_each_entry(port, &portdev->ports, list)
-               if (port->in_vq == vq || port->out_vq == vq)
-                       goto out;
-       port = NULL;
-out:
-       spin_unlock_irqrestore(&portdev->ports_lock, flags);
-       return port;
-}
-
-static bool is_console_port(struct port *port)
-{
-       if (port->cons.hvc)
-               return true;
-       return false;
-}
-
-static inline bool use_multiport(struct ports_device *portdev)
-{
-       /*
-        * This condition can be true when put_chars is called from
-        * early_init
-        */
-       if (!portdev->vdev)
-               return 0;
-       return portdev->vdev->features[0] & (1 << VIRTIO_CONSOLE_F_MULTIPORT);
-}
-
-static void free_buf(struct port_buffer *buf)
-{
-       kfree(buf->buf);
-       kfree(buf);
-}
-
-static struct port_buffer *alloc_buf(size_t buf_size)
-{
-       struct port_buffer *buf;
-
-       buf = kmalloc(sizeof(*buf), GFP_KERNEL);
-       if (!buf)
-               goto fail;
-       buf->buf = kzalloc(buf_size, GFP_KERNEL);
-       if (!buf->buf)
-               goto free_buf;
-       buf->len = 0;
-       buf->offset = 0;
-       buf->size = buf_size;
-       return buf;
-
-free_buf:
-       kfree(buf);
-fail:
-       return NULL;
-}
-
-/* Callers should take appropriate locks */
-static void *get_inbuf(struct port *port)
-{
-       struct port_buffer *buf;
-       struct virtqueue *vq;
-       unsigned int len;
-
-       vq = port->in_vq;
-       buf = virtqueue_get_buf(vq, &len);
-       if (buf) {
-               buf->len = len;
-               buf->offset = 0;
-       }
-       return buf;
-}
-
-/*
- * Create a scatter-gather list representing our input buffer and put
- * it in the queue.
- *
- * Callers should take appropriate locks.
- */
-static int add_inbuf(struct virtqueue *vq, struct port_buffer *buf)
-{
-       struct scatterlist sg[1];
-       int ret;
-
-       sg_init_one(sg, buf->buf, buf->size);
-
-       ret = virtqueue_add_buf(vq, sg, 0, 1, buf);
-       virtqueue_kick(vq);
-       return ret;
-}
-
-/* Discard any unread data this port has. Callers lockers. */
-static void discard_port_data(struct port *port)
-{
-       struct port_buffer *buf;
-       struct virtqueue *vq;
-       unsigned int len;
-       int ret;
-
-       vq = port->in_vq;
-       if (port->inbuf)
-               buf = port->inbuf;
-       else
-               buf = virtqueue_get_buf(vq, &len);
-
-       ret = 0;
-       while (buf) {
-               if (add_inbuf(vq, buf) < 0) {
-                       ret++;
-                       free_buf(buf);
-               }
-               buf = virtqueue_get_buf(vq, &len);
-       }
-       port->inbuf = NULL;
-       if (ret)
-               dev_warn(port->dev, "Errors adding %d buffers back to vq\n",
-                        ret);
-}
-
-static bool port_has_data(struct port *port)
-{
-       unsigned long flags;
-       bool ret;
-
-       spin_lock_irqsave(&port->inbuf_lock, flags);
-       if (port->inbuf) {
-               ret = true;
-               goto out;
-       }
-       port->inbuf = get_inbuf(port);
-       if (port->inbuf) {
-               ret = true;
-               goto out;
-       }
-       ret = false;
-out:
-       spin_unlock_irqrestore(&port->inbuf_lock, flags);
-       return ret;
-}
-
-static ssize_t __send_control_msg(struct ports_device *portdev, u32 port_id,
-                                 unsigned int event, unsigned int value)
-{
-       struct scatterlist sg[1];
-       struct virtio_console_control cpkt;
-       struct virtqueue *vq;
-       unsigned int len;
-
-       if (!use_multiport(portdev))
-               return 0;
-
-       cpkt.id = port_id;
-       cpkt.event = event;
-       cpkt.value = value;
-
-       vq = portdev->c_ovq;
-
-       sg_init_one(sg, &cpkt, sizeof(cpkt));
-       if (virtqueue_add_buf(vq, sg, 1, 0, &cpkt) >= 0) {
-               virtqueue_kick(vq);
-               while (!virtqueue_get_buf(vq, &len))
-                       cpu_relax();
-       }
-       return 0;
-}
-
-static ssize_t send_control_msg(struct port *port, unsigned int event,
-                               unsigned int value)
-{
-       /* Did the port get unplugged before userspace closed it? */
-       if (port->portdev)
-               return __send_control_msg(port->portdev, port->id, event, value);
-       return 0;
-}
-
-/* Callers must take the port->outvq_lock */
-static void reclaim_consumed_buffers(struct port *port)
-{
-       void *buf;
-       unsigned int len;
-
-       while ((buf = virtqueue_get_buf(port->out_vq, &len))) {
-               kfree(buf);
-               port->outvq_full = false;
-       }
-}
-
-static ssize_t send_buf(struct port *port, void *in_buf, size_t in_count,
-                       bool nonblock)
-{
-       struct scatterlist sg[1];
-       struct virtqueue *out_vq;
-       ssize_t ret;
-       unsigned long flags;
-       unsigned int len;
-
-       out_vq = port->out_vq;
-
-       spin_lock_irqsave(&port->outvq_lock, flags);
-
-       reclaim_consumed_buffers(port);
-
-       sg_init_one(sg, in_buf, in_count);
-       ret = virtqueue_add_buf(out_vq, sg, 1, 0, in_buf);
-
-       /* Tell Host to go! */
-       virtqueue_kick(out_vq);
-
-       if (ret < 0) {
-               in_count = 0;
-               goto done;
-       }
-
-       if (ret == 0)
-               port->outvq_full = true;
-
-       if (nonblock)
-               goto done;
-
-       /*
-        * Wait till the host acknowledges it pushed out the data we
-        * sent.  This is done for data from the hvc_console; the tty
-        * operations are performed with spinlocks held so we can't
-        * sleep here.  An alternative would be to copy the data to a
-        * buffer and relax the spinning requirement.  The downside is
-        * we need to kmalloc a GFP_ATOMIC buffer each time the
-        * console driver writes something out.
-        */
-       while (!virtqueue_get_buf(out_vq, &len))
-               cpu_relax();
-done:
-       spin_unlock_irqrestore(&port->outvq_lock, flags);
-       /*
-        * We're expected to return the amount of data we wrote -- all
-        * of it
-        */
-       return in_count;
-}
-
-/*
- * Give out the data that's requested from the buffer that we have
- * queued up.
- */
-static ssize_t fill_readbuf(struct port *port, char *out_buf, size_t out_count,
-                           bool to_user)
-{
-       struct port_buffer *buf;
-       unsigned long flags;
-
-       if (!out_count || !port_has_data(port))
-               return 0;
-
-       buf = port->inbuf;
-       out_count = min(out_count, buf->len - buf->offset);
-
-       if (to_user) {
-               ssize_t ret;
-
-               ret = copy_to_user(out_buf, buf->buf + buf->offset, out_count);
-               if (ret)
-                       return -EFAULT;
-       } else {
-               memcpy(out_buf, buf->buf + buf->offset, out_count);
-       }
-
-       buf->offset += out_count;
-
-       if (buf->offset == buf->len) {
-               /*
-                * We're done using all the data in this buffer.
-                * Re-queue so that the Host can send us more data.
-                */
-               spin_lock_irqsave(&port->inbuf_lock, flags);
-               port->inbuf = NULL;
-
-               if (add_inbuf(port->in_vq, buf) < 0)
-                       dev_warn(port->dev, "failed add_buf\n");
-
-               spin_unlock_irqrestore(&port->inbuf_lock, flags);
-       }
-       /* Return the number of bytes actually copied */
-       return out_count;
-}
-
-/* The condition that must be true for polling to end */
-static bool will_read_block(struct port *port)
-{
-       if (!port->guest_connected) {
-               /* Port got hot-unplugged. Let's exit. */
-               return false;
-       }
-       return !port_has_data(port) && port->host_connected;
-}
-
-static bool will_write_block(struct port *port)
-{
-       bool ret;
-
-       if (!port->guest_connected) {
-               /* Port got hot-unplugged. Let's exit. */
-               return false;
-       }
-       if (!port->host_connected)
-               return true;
-
-       spin_lock_irq(&port->outvq_lock);
-       /*
-        * Check if the Host has consumed any buffers since we last
-        * sent data (this is only applicable for nonblocking ports).
-        */
-       reclaim_consumed_buffers(port);
-       ret = port->outvq_full;
-       spin_unlock_irq(&port->outvq_lock);
-
-       return ret;
-}
-
-static ssize_t port_fops_read(struct file *filp, char __user *ubuf,
-                             size_t count, loff_t *offp)
-{
-       struct port *port;
-       ssize_t ret;
-
-       port = filp->private_data;
-
-       if (!port_has_data(port)) {
-               /*
-                * If nothing's connected on the host just return 0 in
-                * case of list_empty; this tells the userspace app
-                * that there's no connection
-                */
-               if (!port->host_connected)
-                       return 0;
-               if (filp->f_flags & O_NONBLOCK)
-                       return -EAGAIN;
-
-               ret = wait_event_interruptible(port->waitqueue,
-                                              !will_read_block(port));
-               if (ret < 0)
-                       return ret;
-       }
-       /* Port got hot-unplugged. */
-       if (!port->guest_connected)
-               return -ENODEV;
-       /*
-        * We could've received a disconnection message while we were
-        * waiting for more data.
-        *
-        * This check is not clubbed in the if() statement above as we
-        * might receive some data as well as the host could get
-        * disconnected after we got woken up from our wait.  So we
-        * really want to give off whatever data we have and only then
-        * check for host_connected.
-        */
-       if (!port_has_data(port) && !port->host_connected)
-               return 0;
-
-       return fill_readbuf(port, ubuf, count, true);
-}
-
-static ssize_t port_fops_write(struct file *filp, const char __user *ubuf,
-                              size_t count, loff_t *offp)
-{
-       struct port *port;
-       char *buf;
-       ssize_t ret;
-       bool nonblock;
-
-       /* Userspace could be out to fool us */
-       if (!count)
-               return 0;
-
-       port = filp->private_data;
-
-       nonblock = filp->f_flags & O_NONBLOCK;
-
-       if (will_write_block(port)) {
-               if (nonblock)
-                       return -EAGAIN;
-
-               ret = wait_event_interruptible(port->waitqueue,
-                                              !will_write_block(port));
-               if (ret < 0)
-                       return ret;
-       }
-       /* Port got hot-unplugged. */
-       if (!port->guest_connected)
-               return -ENODEV;
-
-       count = min((size_t)(32 * 1024), count);
-
-       buf = kmalloc(count, GFP_KERNEL);
-       if (!buf)
-               return -ENOMEM;
-
-       ret = copy_from_user(buf, ubuf, count);
-       if (ret) {
-               ret = -EFAULT;
-               goto free_buf;
-       }
-
-       /*
-        * We now ask send_buf() to not spin for generic ports -- we
-        * can re-use the same code path that non-blocking file
-        * descriptors take for blocking file descriptors since the
-        * wait is already done and we're certain the write will go
-        * through to the host.
-        */
-       nonblock = true;
-       ret = send_buf(port, buf, count, nonblock);
-
-       if (nonblock && ret > 0)
-               goto out;
-
-free_buf:
-       kfree(buf);
-out:
-       return ret;
-}
-
-static unsigned int port_fops_poll(struct file *filp, poll_table *wait)
-{
-       struct port *port;
-       unsigned int ret;
-
-       port = filp->private_data;
-       poll_wait(filp, &port->waitqueue, wait);
-
-       if (!port->guest_connected) {
-               /* Port got unplugged */
-               return POLLHUP;
-       }
-       ret = 0;
-       if (!will_read_block(port))
-               ret |= POLLIN | POLLRDNORM;
-       if (!will_write_block(port))
-               ret |= POLLOUT;
-       if (!port->host_connected)
-               ret |= POLLHUP;
-
-       return ret;
-}
-
-static void remove_port(struct kref *kref);
-
-static int port_fops_release(struct inode *inode, struct file *filp)
-{
-       struct port *port;
-
-       port = filp->private_data;
-
-       /* Notify host of port being closed */
-       send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 0);
-
-       spin_lock_irq(&port->inbuf_lock);
-       port->guest_connected = false;
-
-       discard_port_data(port);
-
-       spin_unlock_irq(&port->inbuf_lock);
-
-       spin_lock_irq(&port->outvq_lock);
-       reclaim_consumed_buffers(port);
-       spin_unlock_irq(&port->outvq_lock);
-
-       /*
-        * Locks aren't necessary here as a port can't be opened after
-        * unplug, and if a port isn't unplugged, a kref would already
-        * exist for the port.  Plus, taking ports_lock here would
-        * create a dependency on other locks taken by functions
-        * inside remove_port if we're the last holder of the port,
-        * creating many problems.
-        */
-       kref_put(&port->kref, remove_port);
-
-       return 0;
-}
-
-static int port_fops_open(struct inode *inode, struct file *filp)
-{
-       struct cdev *cdev = inode->i_cdev;
-       struct port *port;
-       int ret;
-
-       port = find_port_by_devt(cdev->dev);
-       filp->private_data = port;
-
-       /* Prevent against a port getting hot-unplugged at the same time */
-       spin_lock_irq(&port->portdev->ports_lock);
-       kref_get(&port->kref);
-       spin_unlock_irq(&port->portdev->ports_lock);
-
-       /*
-        * Don't allow opening of console port devices -- that's done
-        * via /dev/hvc
-        */
-       if (is_console_port(port)) {
-               ret = -ENXIO;
-               goto out;
-       }
-
-       /* Allow only one process to open a particular port at a time */
-       spin_lock_irq(&port->inbuf_lock);
-       if (port->guest_connected) {
-               spin_unlock_irq(&port->inbuf_lock);
-               ret = -EMFILE;
-               goto out;
-       }
-
-       port->guest_connected = true;
-       spin_unlock_irq(&port->inbuf_lock);
-
-       spin_lock_irq(&port->outvq_lock);
-       /*
-        * There might be a chance that we missed reclaiming a few
-        * buffers in the window of the port getting previously closed
-        * and opening now.
-        */
-       reclaim_consumed_buffers(port);
-       spin_unlock_irq(&port->outvq_lock);
-
-       nonseekable_open(inode, filp);
-
-       /* Notify host of port being opened */
-       send_control_msg(filp->private_data, VIRTIO_CONSOLE_PORT_OPEN, 1);
-
-       return 0;
-out:
-       kref_put(&port->kref, remove_port);
-       return ret;
-}
-
-static int port_fops_fasync(int fd, struct file *filp, int mode)
-{
-       struct port *port;
-
-       port = filp->private_data;
-       return fasync_helper(fd, filp, mode, &port->async_queue);
-}
-
-/*
- * The file operations that we support: programs in the guest can open
- * a console device, read from it, write to it, poll for data and
- * close it.  The devices are at
- *   /dev/vport<device number>p<port number>
- */
-static const struct file_operations port_fops = {
-       .owner = THIS_MODULE,
-       .open  = port_fops_open,
-       .read  = port_fops_read,
-       .write = port_fops_write,
-       .poll  = port_fops_poll,
-       .release = port_fops_release,
-       .fasync = port_fops_fasync,
-       .llseek = no_llseek,
-};
-
-/*
- * The put_chars() callback is pretty straightforward.
- *
- * We turn the characters into a scatter-gather list, add it to the
- * output queue and then kick the Host.  Then we sit here waiting for
- * it to finish: inefficient in theory, but in practice
- * implementations will do it immediately (lguest's Launcher does).
- */
-static int put_chars(u32 vtermno, const char *buf, int count)
-{
-       struct port *port;
-
-       if (unlikely(early_put_chars))
-               return early_put_chars(vtermno, buf, count);
-
-       port = find_port_by_vtermno(vtermno);
-       if (!port)
-               return -EPIPE;
-
-       return send_buf(port, (void *)buf, count, false);
-}
-
-/*
- * get_chars() is the callback from the hvc_console infrastructure
- * when an interrupt is received.
- *
- * We call out to fill_readbuf that gets us the required data from the
- * buffers that are queued up.
- */
-static int get_chars(u32 vtermno, char *buf, int count)
-{
-       struct port *port;
-
-       /* If we've not set up the port yet, we have no input to give. */
-       if (unlikely(early_put_chars))
-               return 0;
-
-       port = find_port_by_vtermno(vtermno);
-       if (!port)
-               return -EPIPE;
-
-       /* If we don't have an input queue yet, we can't get input. */
-       BUG_ON(!port->in_vq);
-
-       return fill_readbuf(port, buf, count, false);
-}
-
-static void resize_console(struct port *port)
-{
-       struct virtio_device *vdev;
-
-       /* The port could have been hot-unplugged */
-       if (!port || !is_console_port(port))
-               return;
-
-       vdev = port->portdev->vdev;
-       if (virtio_has_feature(vdev, VIRTIO_CONSOLE_F_SIZE))
-               hvc_resize(port->cons.hvc, port->cons.ws);
-}
-
-/* We set the configuration at this point, since we now have a tty */
-static int notifier_add_vio(struct hvc_struct *hp, int data)
-{
-       struct port *port;
-
-       port = find_port_by_vtermno(hp->vtermno);
-       if (!port)
-               return -EINVAL;
-
-       hp->irq_requested = 1;
-       resize_console(port);
-
-       return 0;
-}
-
-static void notifier_del_vio(struct hvc_struct *hp, int data)
-{
-       hp->irq_requested = 0;
-}
-
-/* The operations for console ports. */
-static const struct hv_ops hv_ops = {
-       .get_chars = get_chars,
-       .put_chars = put_chars,
-       .notifier_add = notifier_add_vio,
-       .notifier_del = notifier_del_vio,
-       .notifier_hangup = notifier_del_vio,
-};
-
-/*
- * Console drivers are initialized very early so boot messages can go
- * out, so we do things slightly differently from the generic virtio
- * initialization of the net and block drivers.
- *
- * At this stage, the console is output-only.  It's too early to set
- * up a virtqueue, so we let the drivers do some boutique early-output
- * thing.
- */
-int __init virtio_cons_early_init(int (*put_chars)(u32, const char *, int))
-{
-       early_put_chars = put_chars;
-       return hvc_instantiate(0, 0, &hv_ops);
-}
-
-int init_port_console(struct port *port)
-{
-       int ret;
-
-       /*
-        * The Host's telling us this port is a console port.  Hook it
-        * up with an hvc console.
-        *
-        * To set up and manage our virtual console, we call
-        * hvc_alloc().
-        *
-        * The first argument of hvc_alloc() is the virtual console
-        * number.  The second argument is the parameter for the
-        * notification mechanism (like irq number).  We currently
-        * leave this as zero, virtqueues have implicit notifications.
-        *
-        * The third argument is a "struct hv_ops" containing the
-        * put_chars() get_chars(), notifier_add() and notifier_del()
-        * pointers.  The final argument is the output buffer size: we
-        * can do any size, so we put PAGE_SIZE here.
-        */
-       port->cons.vtermno = pdrvdata.next_vtermno;
-
-       port->cons.hvc = hvc_alloc(port->cons.vtermno, 0, &hv_ops, PAGE_SIZE);
-       if (IS_ERR(port->cons.hvc)) {
-               ret = PTR_ERR(port->cons.hvc);
-               dev_err(port->dev,
-                       "error %d allocating hvc for port\n", ret);
-               port->cons.hvc = NULL;
-               return ret;
-       }
-       spin_lock_irq(&pdrvdata_lock);
-       pdrvdata.next_vtermno++;
-       list_add_tail(&port->cons.list, &pdrvdata.consoles);
-       spin_unlock_irq(&pdrvdata_lock);
-       port->guest_connected = true;
-
-       /*
-        * Start using the new console output if this is the first
-        * console to come up.
-        */
-       if (early_put_chars)
-               early_put_chars = NULL;
-
-       /* Notify host of port being opened */
-       send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 1);
-
-       return 0;
-}
-
-static ssize_t show_port_name(struct device *dev,
-                             struct device_attribute *attr, char *buffer)
-{
-       struct port *port;
-
-       port = dev_get_drvdata(dev);
-
-       return sprintf(buffer, "%s\n", port->name);
-}
-
-static DEVICE_ATTR(name, S_IRUGO, show_port_name, NULL);
-
-static struct attribute *port_sysfs_entries[] = {
-       &dev_attr_name.attr,
-       NULL
-};
-
-static struct attribute_group port_attribute_group = {
-       .name = NULL,           /* put in device directory */
-       .attrs = port_sysfs_entries,
-};
-
-static int debugfs_open(struct inode *inode, struct file *filp)
-{
-       filp->private_data = inode->i_private;
-       return 0;
-}
-
-static ssize_t debugfs_read(struct file *filp, char __user *ubuf,
-                           size_t count, loff_t *offp)
-{
-       struct port *port;
-       char *buf;
-       ssize_t ret, out_offset, out_count;
-
-       out_count = 1024;
-       buf = kmalloc(out_count, GFP_KERNEL);
-       if (!buf)
-               return -ENOMEM;
-
-       port = filp->private_data;
-       out_offset = 0;
-       out_offset += snprintf(buf + out_offset, out_count,
-                              "name: %s\n", port->name ? port->name : "");
-       out_offset += snprintf(buf + out_offset, out_count - out_offset,
-                              "guest_connected: %d\n", port->guest_connected);
-       out_offset += snprintf(buf + out_offset, out_count - out_offset,
-                              "host_connected: %d\n", port->host_connected);
-       out_offset += snprintf(buf + out_offset, out_count - out_offset,
-                              "outvq_full: %d\n", port->outvq_full);
-       out_offset += snprintf(buf + out_offset, out_count - out_offset,
-                              "is_console: %s\n",
-                              is_console_port(port) ? "yes" : "no");
-       out_offset += snprintf(buf + out_offset, out_count - out_offset,
-                              "console_vtermno: %u\n", port->cons.vtermno);
-
-       ret = simple_read_from_buffer(ubuf, count, offp, buf, out_offset);
-       kfree(buf);
-       return ret;
-}
-
-static const struct file_operations port_debugfs_ops = {
-       .owner = THIS_MODULE,
-       .open  = debugfs_open,
-       .read  = debugfs_read,
-};
-
-static void set_console_size(struct port *port, u16 rows, u16 cols)
-{
-       if (!port || !is_console_port(port))
-               return;
-
-       port->cons.ws.ws_row = rows;
-       port->cons.ws.ws_col = cols;
-}
-
-static unsigned int fill_queue(struct virtqueue *vq, spinlock_t *lock)
-{
-       struct port_buffer *buf;
-       unsigned int nr_added_bufs;
-       int ret;
-
-       nr_added_bufs = 0;
-       do {
-               buf = alloc_buf(PAGE_SIZE);
-               if (!buf)
-                       break;
-
-               spin_lock_irq(lock);
-               ret = add_inbuf(vq, buf);
-               if (ret < 0) {
-                       spin_unlock_irq(lock);
-                       free_buf(buf);
-                       break;
-               }
-               nr_added_bufs++;
-               spin_unlock_irq(lock);
-       } while (ret > 0);
-
-       return nr_added_bufs;
-}
-
-static void send_sigio_to_port(struct port *port)
-{
-       if (port->async_queue && port->guest_connected)
-               kill_fasync(&port->async_queue, SIGIO, POLL_OUT);
-}
-
-static int add_port(struct ports_device *portdev, u32 id)
-{
-       char debugfs_name[16];
-       struct port *port;
-       struct port_buffer *buf;
-       dev_t devt;
-       unsigned int nr_added_bufs;
-       int err;
-
-       port = kmalloc(sizeof(*port), GFP_KERNEL);
-       if (!port) {
-               err = -ENOMEM;
-               goto fail;
-       }
-       kref_init(&port->kref);
-
-       port->portdev = portdev;
-       port->id = id;
-
-       port->name = NULL;
-       port->inbuf = NULL;
-       port->cons.hvc = NULL;
-       port->async_queue = NULL;
-
-       port->cons.ws.ws_row = port->cons.ws.ws_col = 0;
-
-       port->host_connected = port->guest_connected = false;
-
-       port->outvq_full = false;
-
-       port->in_vq = portdev->in_vqs[port->id];
-       port->out_vq = portdev->out_vqs[port->id];
-
-       port->cdev = cdev_alloc();
-       if (!port->cdev) {
-               dev_err(&port->portdev->vdev->dev, "Error allocating cdev\n");
-               err = -ENOMEM;
-               goto free_port;
-       }
-       port->cdev->ops = &port_fops;
-
-       devt = MKDEV(portdev->chr_major, id);
-       err = cdev_add(port->cdev, devt, 1);
-       if (err < 0) {
-               dev_err(&port->portdev->vdev->dev,
-                       "Error %d adding cdev for port %u\n", err, id);
-               goto free_cdev;
-       }
-       port->dev = device_create(pdrvdata.class, &port->portdev->vdev->dev,
-                                 devt, port, "vport%up%u",
-                                 port->portdev->drv_index, id);
-       if (IS_ERR(port->dev)) {
-               err = PTR_ERR(port->dev);
-               dev_err(&port->portdev->vdev->dev,
-                       "Error %d creating device for port %u\n",
-                       err, id);
-               goto free_cdev;
-       }
-
-       spin_lock_init(&port->inbuf_lock);
-       spin_lock_init(&port->outvq_lock);
-       init_waitqueue_head(&port->waitqueue);
-
-       /* Fill the in_vq with buffers so the host can send us data. */
-       nr_added_bufs = fill_queue(port->in_vq, &port->inbuf_lock);
-       if (!nr_added_bufs) {
-               dev_err(port->dev, "Error allocating inbufs\n");
-               err = -ENOMEM;
-               goto free_device;
-       }
-
-       /*
-        * If we're not using multiport support, this has to be a console port
-        */
-       if (!use_multiport(port->portdev)) {
-               err = init_port_console(port);
-               if (err)
-                       goto free_inbufs;
-       }
-
-       spin_lock_irq(&portdev->ports_lock);
-       list_add_tail(&port->list, &port->portdev->ports);
-       spin_unlock_irq(&portdev->ports_lock);
-
-       /*
-        * Tell the Host we're set so that it can send us various
-        * configuration parameters for this port (eg, port name,
-        * caching, whether this is a console port, etc.)
-        */
-       send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1);
-
-       if (pdrvdata.debugfs_dir) {
-               /*
-                * Finally, create the debugfs file that we can use to
-                * inspect a port's state at any time
-                */
-               sprintf(debugfs_name, "vport%up%u",
-                       port->portdev->drv_index, id);
-               port->debugfs_file = debugfs_create_file(debugfs_name, 0444,
-                                                        pdrvdata.debugfs_dir,
-                                                        port,
-                                                        &port_debugfs_ops);
-       }
-       return 0;
-
-free_inbufs:
-       while ((buf = virtqueue_detach_unused_buf(port->in_vq)))
-               free_buf(buf);
-free_device:
-       device_destroy(pdrvdata.class, port->dev->devt);
-free_cdev:
-       cdev_del(port->cdev);
-free_port:
-       kfree(port);
-fail:
-       /* The host might want to notify management sw about port add failure */
-       __send_control_msg(portdev, id, VIRTIO_CONSOLE_PORT_READY, 0);
-       return err;
-}
-
-/* No users remain, remove all port-specific data. */
-static void remove_port(struct kref *kref)
-{
-       struct port *port;
-
-       port = container_of(kref, struct port, kref);
-
-       sysfs_remove_group(&port->dev->kobj, &port_attribute_group);
-       device_destroy(pdrvdata.class, port->dev->devt);
-       cdev_del(port->cdev);
-
-       kfree(port->name);
-
-       debugfs_remove(port->debugfs_file);
-
-       kfree(port);
-}
-
-/*
- * Port got unplugged.  Remove port from portdev's list and drop the
- * kref reference.  If no userspace has this port opened, it will
- * result in immediate removal the port.
- */
-static void unplug_port(struct port *port)
-{
-       struct port_buffer *buf;
-
-       spin_lock_irq(&port->portdev->ports_lock);
-       list_del(&port->list);
-       spin_unlock_irq(&port->portdev->ports_lock);
-
-       if (port->guest_connected) {
-               port->guest_connected = false;
-               port->host_connected = false;
-               wake_up_interruptible(&port->waitqueue);
-
-               /* Let the app know the port is going down. */
-               send_sigio_to_port(port);
-       }
-
-       if (is_console_port(port)) {
-               spin_lock_irq(&pdrvdata_lock);
-               list_del(&port->cons.list);
-               spin_unlock_irq(&pdrvdata_lock);
-#if 0
-               /*
-                * hvc_remove() not called as removing one hvc port
-                * results in other hvc ports getting frozen.
-                *
-                * Once this is resolved in hvc, this functionality
-                * will be enabled.  Till that is done, the -EPIPE
-                * return from get_chars() above will help
-                * hvc_console.c to clean up on ports we remove here.
-                */
-               hvc_remove(port->cons.hvc);
-#endif
-       }
-
-       /* Remove unused data this port might have received. */
-       discard_port_data(port);
-
-       reclaim_consumed_buffers(port);
-
-       /* Remove buffers we queued up for the Host to send us data in. */
-       while ((buf = virtqueue_detach_unused_buf(port->in_vq)))
-               free_buf(buf);
-
-       /*
-        * We should just assume the device itself has gone off --
-        * else a close on an open port later will try to send out a
-        * control message.
-        */
-       port->portdev = NULL;
-
-       /*
-        * Locks around here are not necessary - a port can't be
-        * opened after we removed the port struct from ports_list
-        * above.
-        */
-       kref_put(&port->kref, remove_port);
-}
-
-/* Any private messages that the Host and Guest want to share */
-static void handle_control_message(struct ports_device *portdev,
-                                  struct port_buffer *buf)
-{
-       struct virtio_console_control *cpkt;
-       struct port *port;
-       size_t name_size;
-       int err;
-
-       cpkt = (struct virtio_console_control *)(buf->buf + buf->offset);
-
-       port = find_port_by_id(portdev, cpkt->id);
-       if (!port && cpkt->event != VIRTIO_CONSOLE_PORT_ADD) {
-               /* No valid header at start of buffer.  Drop it. */
-               dev_dbg(&portdev->vdev->dev,
-                       "Invalid index %u in control packet\n", cpkt->id);
-               return;
-       }
-
-       switch (cpkt->event) {
-       case VIRTIO_CONSOLE_PORT_ADD:
-               if (port) {
-                       dev_dbg(&portdev->vdev->dev,
-                               "Port %u already added\n", port->id);
-                       send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1);
-                       break;
-               }
-               if (cpkt->id >= portdev->config.max_nr_ports) {
-                       dev_warn(&portdev->vdev->dev,
-                               "Request for adding port with out-of-bound id %u, max. supported id: %u\n",
-                               cpkt->id, portdev->config.max_nr_ports - 1);
-                       break;
-               }
-               add_port(portdev, cpkt->id);
-               break;
-       case VIRTIO_CONSOLE_PORT_REMOVE:
-               unplug_port(port);
-               break;
-       case VIRTIO_CONSOLE_CONSOLE_PORT:
-               if (!cpkt->value)
-                       break;
-               if (is_console_port(port))
-                       break;
-
-               init_port_console(port);
-               /*
-                * Could remove the port here in case init fails - but
-                * have to notify the host first.
-                */
-               break;
-       case VIRTIO_CONSOLE_RESIZE: {
-               struct {
-                       __u16 rows;
-                       __u16 cols;
-               } size;
-
-               if (!is_console_port(port))
-                       break;
-
-               memcpy(&size, buf->buf + buf->offset + sizeof(*cpkt),
-                      sizeof(size));
-               set_console_size(port, size.rows, size.cols);
-
-               port->cons.hvc->irq_requested = 1;
-               resize_console(port);
-               break;
-       }
-       case VIRTIO_CONSOLE_PORT_OPEN:
-               port->host_connected = cpkt->value;
-               wake_up_interruptible(&port->waitqueue);
-               /*
-                * If the host port got closed and the host had any
-                * unconsumed buffers, we'll be able to reclaim them
-                * now.
-                */
-               spin_lock_irq(&port->outvq_lock);
-               reclaim_consumed_buffers(port);
-               spin_unlock_irq(&port->outvq_lock);
-
-               /*
-                * If the guest is connected, it'll be interested in
-                * knowing the host connection state changed.
-                */
-               send_sigio_to_port(port);
-               break;
-       case VIRTIO_CONSOLE_PORT_NAME:
-               /*
-                * Skip the size of the header and the cpkt to get the size
-                * of the name that was sent
-                */
-               name_size = buf->len - buf->offset - sizeof(*cpkt) + 1;
-
-               port->name = kmalloc(name_size, GFP_KERNEL);
-               if (!port->name) {
-                       dev_err(port->dev,
-                               "Not enough space to store port name\n");
-                       break;
-               }
-               strncpy(port->name, buf->buf + buf->offset + sizeof(*cpkt),
-                       name_size - 1);
-               port->name[name_size - 1] = 0;
-
-               /*
-                * Since we only have one sysfs attribute, 'name',
-                * create it only if we have a name for the port.
-                */
-               err = sysfs_create_group(&port->dev->kobj,
-                                        &port_attribute_group);
-               if (err) {
-                       dev_err(port->dev,
-                               "Error %d creating sysfs device attributes\n",
-                               err);
-               } else {
-                       /*
-                        * Generate a udev event so that appropriate
-                        * symlinks can be created based on udev
-                        * rules.
-                        */
-                       kobject_uevent(&port->dev->kobj, KOBJ_CHANGE);
-               }
-               break;
-       }
-}
-
-static void control_work_handler(struct work_struct *work)
-{
-       struct ports_device *portdev;
-       struct virtqueue *vq;
-       struct port_buffer *buf;
-       unsigned int len;
-
-       portdev = container_of(work, struct ports_device, control_work);
-       vq = portdev->c_ivq;
-
-       spin_lock(&portdev->cvq_lock);
-       while ((buf = virtqueue_get_buf(vq, &len))) {
-               spin_unlock(&portdev->cvq_lock);
-
-               buf->len = len;
-               buf->offset = 0;
-
-               handle_control_message(portdev, buf);
-
-               spin_lock(&portdev->cvq_lock);
-               if (add_inbuf(portdev->c_ivq, buf) < 0) {
-                       dev_warn(&portdev->vdev->dev,
-                                "Error adding buffer to queue\n");
-                       free_buf(buf);
-               }
-       }
-       spin_unlock(&portdev->cvq_lock);
-}
-
-static void in_intr(struct virtqueue *vq)
-{
-       struct port *port;
-       unsigned long flags;
-
-       port = find_port_by_vq(vq->vdev->priv, vq);
-       if (!port)
-               return;
-
-       spin_lock_irqsave(&port->inbuf_lock, flags);
-       if (!port->inbuf)
-               port->inbuf = get_inbuf(port);
-
-       /*
-        * Don't queue up data when port is closed.  This condition
-        * can be reached when a console port is not yet connected (no
-        * tty is spawned) and the host sends out data to console
-        * ports.  For generic serial ports, the host won't
-        * (shouldn't) send data till the guest is connected.
-        */
-       if (!port->guest_connected)
-               discard_port_data(port);
-
-       spin_unlock_irqrestore(&port->inbuf_lock, flags);
-
-       wake_up_interruptible(&port->waitqueue);
-
-       /* Send a SIGIO indicating new data in case the process asked for it */
-       send_sigio_to_port(port);
-
-       if (is_console_port(port) && hvc_poll(port->cons.hvc))
-               hvc_kick();
-}
-
-static void control_intr(struct virtqueue *vq)
-{
-       struct ports_device *portdev;
-
-       portdev = vq->vdev->priv;
-       schedule_work(&portdev->control_work);
-}
-
-static void config_intr(struct virtio_device *vdev)
-{
-       struct ports_device *portdev;
-
-       portdev = vdev->priv;
-
-       if (!use_multiport(portdev)) {
-               struct port *port;
-               u16 rows, cols;
-
-               vdev->config->get(vdev,
-                                 offsetof(struct virtio_console_config, cols),
-                                 &cols, sizeof(u16));
-               vdev->config->get(vdev,
-                                 offsetof(struct virtio_console_config, rows),
-                                 &rows, sizeof(u16));
-
-               port = find_port_by_id(portdev, 0);
-               set_console_size(port, rows, cols);
-
-               /*
-                * We'll use this way of resizing only for legacy
-                * support.  For newer userspace
-                * (VIRTIO_CONSOLE_F_MULTPORT+), use control messages
-                * to indicate console size changes so that it can be
-                * done per-port.
-                */
-               resize_console(port);
-       }
-}
-
-static int init_vqs(struct ports_device *portdev)
-{
-       vq_callback_t **io_callbacks;
-       char **io_names;
-       struct virtqueue **vqs;
-       u32 i, j, nr_ports, nr_queues;
-       int err;
-
-       nr_ports = portdev->config.max_nr_ports;
-       nr_queues = use_multiport(portdev) ? (nr_ports + 1) * 2 : 2;
-
-       vqs = kmalloc(nr_queues * sizeof(struct virtqueue *), GFP_KERNEL);
-       io_callbacks = kmalloc(nr_queues * sizeof(vq_callback_t *), GFP_KERNEL);
-       io_names = kmalloc(nr_queues * sizeof(char *), GFP_KERNEL);
-       portdev->in_vqs = kmalloc(nr_ports * sizeof(struct virtqueue *),
-                                 GFP_KERNEL);
-       portdev->out_vqs = kmalloc(nr_ports * sizeof(struct virtqueue *),
-                                  GFP_KERNEL);
-       if (!vqs || !io_callbacks || !io_names || !portdev->in_vqs ||
-                       !portdev->out_vqs) {
-               err = -ENOMEM;
-               goto free;
-       }
-
-       /*
-        * For backward compat (newer host but older guest), the host
-        * spawns a console port first and also inits the vqs for port
-        * 0 before others.
-        */
-       j = 0;
-       io_callbacks[j] = in_intr;
-       io_callbacks[j + 1] = NULL;
-       io_names[j] = "input";
-       io_names[j + 1] = "output";
-       j += 2;
-
-       if (use_multiport(portdev)) {
-               io_callbacks[j] = control_intr;
-               io_callbacks[j + 1] = NULL;
-               io_names[j] = "control-i";
-               io_names[j + 1] = "control-o";
-
-               for (i = 1; i < nr_ports; i++) {
-                       j += 2;
-                       io_callbacks[j] = in_intr;
-                       io_callbacks[j + 1] = NULL;
-                       io_names[j] = "input";
-                       io_names[j + 1] = "output";
-               }
-       }
-       /* Find the queues. */
-       err = portdev->vdev->config->find_vqs(portdev->vdev, nr_queues, vqs,
-                                             io_callbacks,
-                                             (const char **)io_names);
-       if (err)
-               goto free;
-
-       j = 0;
-       portdev->in_vqs[0] = vqs[0];
-       portdev->out_vqs[0] = vqs[1];
-       j += 2;
-       if (use_multiport(portdev)) {
-               portdev->c_ivq = vqs[j];
-               portdev->c_ovq = vqs[j + 1];
-
-               for (i = 1; i < nr_ports; i++) {
-                       j += 2;
-                       portdev->in_vqs[i] = vqs[j];
-                       portdev->out_vqs[i] = vqs[j + 1];
-               }
-       }
-       kfree(io_names);
-       kfree(io_callbacks);
-       kfree(vqs);
-
-       return 0;
-
-free:
-       kfree(portdev->out_vqs);
-       kfree(portdev->in_vqs);
-       kfree(io_names);
-       kfree(io_callbacks);
-       kfree(vqs);
-
-       return err;
-}
-
-static const struct file_operations portdev_fops = {
-       .owner = THIS_MODULE,
-};
-
-/*
- * Once we're further in boot, we get probed like any other virtio
- * device.
- *
- * If the host also supports multiple console ports, we check the
- * config space to see how many ports the host has spawned.  We
- * initialize each port found.
- */
-static int __devinit virtcons_probe(struct virtio_device *vdev)
-{
-       struct ports_device *portdev;
-       int err;
-       bool multiport;
-
-       portdev = kmalloc(sizeof(*portdev), GFP_KERNEL);
-       if (!portdev) {
-               err = -ENOMEM;
-               goto fail;
-       }
-
-       /* Attach this portdev to this virtio_device, and vice-versa. */
-       portdev->vdev = vdev;
-       vdev->priv = portdev;
-
-       spin_lock_irq(&pdrvdata_lock);
-       portdev->drv_index = pdrvdata.index++;
-       spin_unlock_irq(&pdrvdata_lock);
-
-       portdev->chr_major = register_chrdev(0, "virtio-portsdev",
-                                            &portdev_fops);
-       if (portdev->chr_major < 0) {
-               dev_err(&vdev->dev,
-                       "Error %d registering chrdev for device %u\n",
-                       portdev->chr_major, portdev->drv_index);
-               err = portdev->chr_major;
-               goto free;
-       }
-
-       multiport = false;
-       portdev->config.max_nr_ports = 1;
-       if (virtio_has_feature(vdev, VIRTIO_CONSOLE_F_MULTIPORT)) {
-               multiport = true;
-               vdev->features[0] |= 1 << VIRTIO_CONSOLE_F_MULTIPORT;
-
-               vdev->config->get(vdev, offsetof(struct virtio_console_config,
-                                                max_nr_ports),
-                                 &portdev->config.max_nr_ports,
-                                 sizeof(portdev->config.max_nr_ports));
-       }
-
-       /* Let the Host know we support multiple ports.*/
-       vdev->config->finalize_features(vdev);
-
-       err = init_vqs(portdev);
-       if (err < 0) {
-               dev_err(&vdev->dev, "Error %d initializing vqs\n", err);
-               goto free_chrdev;
-       }
-
-       spin_lock_init(&portdev->ports_lock);
-       INIT_LIST_HEAD(&portdev->ports);
-
-       if (multiport) {
-               unsigned int nr_added_bufs;
-
-               spin_lock_init(&portdev->cvq_lock);
-               INIT_WORK(&portdev->control_work, &control_work_handler);
-
-               nr_added_bufs = fill_queue(portdev->c_ivq, &portdev->cvq_lock);
-               if (!nr_added_bufs) {
-                       dev_err(&vdev->dev,
-                               "Error allocating buffers for control queue\n");
-                       err = -ENOMEM;
-                       goto free_vqs;
-               }
-       } else {
-               /*
-                * For backward compatibility: Create a console port
-                * if we're running on older host.
-                */
-               add_port(portdev, 0);
-       }
-
-       spin_lock_irq(&pdrvdata_lock);
-       list_add_tail(&portdev->list, &pdrvdata.portdevs);
-       spin_unlock_irq(&pdrvdata_lock);
-
-       __send_control_msg(portdev, VIRTIO_CONSOLE_BAD_ID,
-                          VIRTIO_CONSOLE_DEVICE_READY, 1);
-       return 0;
-
-free_vqs:
-       /* The host might want to notify mgmt sw about device add failure */
-       __send_control_msg(portdev, VIRTIO_CONSOLE_BAD_ID,
-                          VIRTIO_CONSOLE_DEVICE_READY, 0);
-       vdev->config->del_vqs(vdev);
-       kfree(portdev->in_vqs);
-       kfree(portdev->out_vqs);
-free_chrdev:
-       unregister_chrdev(portdev->chr_major, "virtio-portsdev");
-free:
-       kfree(portdev);
-fail:
-       return err;
-}
-
-static void virtcons_remove(struct virtio_device *vdev)
-{
-       struct ports_device *portdev;
-       struct port *port, *port2;
-
-       portdev = vdev->priv;
-
-       spin_lock_irq(&pdrvdata_lock);
-       list_del(&portdev->list);
-       spin_unlock_irq(&pdrvdata_lock);
-
-       /* Disable interrupts for vqs */
-       vdev->config->reset(vdev);
-       /* Finish up work that's lined up */
-       cancel_work_sync(&portdev->control_work);
-
-       list_for_each_entry_safe(port, port2, &portdev->ports, list)
-               unplug_port(port);
-
-       unregister_chrdev(portdev->chr_major, "virtio-portsdev");
-
-       /*
-        * When yanking out a device, we immediately lose the
-        * (device-side) queues.  So there's no point in keeping the
-        * guest side around till we drop our final reference.  This
-        * also means that any ports which are in an open state will
-        * have to just stop using the port, as the vqs are going
-        * away.
-        */
-       if (use_multiport(portdev)) {
-               struct port_buffer *buf;
-               unsigned int len;
-
-               while ((buf = virtqueue_get_buf(portdev->c_ivq, &len)))
-                       free_buf(buf);
-
-               while ((buf = virtqueue_detach_unused_buf(portdev->c_ivq)))
-                       free_buf(buf);
-       }
-
-       vdev->config->del_vqs(vdev);
-       kfree(portdev->in_vqs);
-       kfree(portdev->out_vqs);
-
-       kfree(portdev);
-}
-
-static struct virtio_device_id id_table[] = {
-       { VIRTIO_ID_CONSOLE, VIRTIO_DEV_ANY_ID },
-       { 0 },
-};
-
-static unsigned int features[] = {
-       VIRTIO_CONSOLE_F_SIZE,
-       VIRTIO_CONSOLE_F_MULTIPORT,
-};
-
-static struct virtio_driver virtio_console = {
-       .feature_table = features,
-       .feature_table_size = ARRAY_SIZE(features),
-       .driver.name =  KBUILD_MODNAME,
-       .driver.owner = THIS_MODULE,
-       .id_table =     id_table,
-       .probe =        virtcons_probe,
-       .remove =       virtcons_remove,
-       .config_changed = config_intr,
-};
-
-static int __init init(void)
-{
-       int err;
-
-       pdrvdata.class = class_create(THIS_MODULE, "virtio-ports");
-       if (IS_ERR(pdrvdata.class)) {
-               err = PTR_ERR(pdrvdata.class);
-               pr_err("Error %d creating virtio-ports class\n", err);
-               return err;
-       }
-
-       pdrvdata.debugfs_dir = debugfs_create_dir("virtio-ports", NULL);
-       if (!pdrvdata.debugfs_dir) {
-               pr_warning("Error %ld creating debugfs dir for virtio-ports\n",
-                          PTR_ERR(pdrvdata.debugfs_dir));
-       }
-       INIT_LIST_HEAD(&pdrvdata.consoles);
-       INIT_LIST_HEAD(&pdrvdata.portdevs);
-
-       return register_virtio_driver(&virtio_console);
-}
-
-static void __exit fini(void)
-{
-       unregister_virtio_driver(&virtio_console);
-
-       class_destroy(pdrvdata.class);
-       if (pdrvdata.debugfs_dir)
-               debugfs_remove_recursive(pdrvdata.debugfs_dir);
-}
-module_init(init);
-module_exit(fini);
-
-MODULE_DEVICE_TABLE(virtio, id_table);
-MODULE_DESCRIPTION("Virtio console driver");
-MODULE_LICENSE("GPL");
index c43ef48..d3685f0 100644 (file)
@@ -9,3 +9,4 @@ obj-$(CONFIG_N_GSM)             += n_gsm.o
 obj-$(CONFIG_R3964)            += n_r3964.o
 
 obj-y                          += vt/
+obj-$(CONFIG_HVC_DRIVER)       += hvc/
diff --git a/drivers/tty/hvc/Makefile b/drivers/tty/hvc/Makefile
new file mode 100644 (file)
index 0000000..e6bed5f
--- /dev/null
@@ -0,0 +1,13 @@
+obj-$(CONFIG_HVC_CONSOLE)      += hvc_vio.o hvsi.o
+obj-$(CONFIG_HVC_ISERIES)      += hvc_iseries.o
+obj-$(CONFIG_HVC_RTAS)         += hvc_rtas.o
+obj-$(CONFIG_HVC_TILE)         += hvc_tile.o
+obj-$(CONFIG_HVC_DCC)          += hvc_dcc.o
+obj-$(CONFIG_HVC_BEAT)         += hvc_beat.o
+obj-$(CONFIG_HVC_DRIVER)       += hvc_console.o
+obj-$(CONFIG_HVC_IRQ)          += hvc_irq.o
+obj-$(CONFIG_HVC_XEN)          += hvc_xen.o
+obj-$(CONFIG_HVC_IUCV)         += hvc_iucv.o
+obj-$(CONFIG_HVC_UDBG)         += hvc_udbg.o
+obj-$(CONFIG_HVCS)             += hvcs.o
+obj-$(CONFIG_VIRTIO_CONSOLE)   += virtio_console.o
diff --git a/drivers/tty/hvc/hvc_beat.c b/drivers/tty/hvc/hvc_beat.c
new file mode 100644 (file)
index 0000000..5fe4631
--- /dev/null
@@ -0,0 +1,134 @@
+/*
+ * Beat hypervisor console driver
+ *
+ * (C) Copyright 2006 TOSHIBA CORPORATION
+ *
+ * This code is based on drivers/char/hvc_rtas.c:
+ * (C) Copyright IBM Corporation 2001-2005
+ * (C) Copyright Red Hat, Inc. 2005
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/string.h>
+#include <linux/console.h>
+#include <asm/prom.h>
+#include <asm/hvconsole.h>
+#include <asm/firmware.h>
+
+#include "hvc_console.h"
+
+extern int64_t beat_get_term_char(uint64_t, uint64_t *, uint64_t *, uint64_t *);
+extern int64_t beat_put_term_char(uint64_t, uint64_t, uint64_t, uint64_t);
+
+struct hvc_struct *hvc_beat_dev = NULL;
+
+/* bug: only one queue is available regardless of vtermno */
+static int hvc_beat_get_chars(uint32_t vtermno, char *buf, int cnt)
+{
+       static unsigned char q[sizeof(unsigned long) * 2]
+               __attribute__((aligned(sizeof(unsigned long))));
+       static int qlen = 0;
+       u64 got;
+
+again:
+       if (qlen) {
+               if (qlen > cnt) {
+                       memcpy(buf, q, cnt);
+                       qlen -= cnt;
+                       memmove(q + cnt, q, qlen);
+                       return cnt;
+               } else {        /* qlen <= cnt */
+                       int     r;
+
+                       memcpy(buf, q, qlen);
+                       r = qlen;
+                       qlen = 0;
+                       return r;
+               }
+       }
+       if (beat_get_term_char(vtermno, &got,
+               ((u64 *)q), ((u64 *)q) + 1) == 0) {
+               qlen = got;
+               goto again;
+       }
+       return 0;
+}
+
+static int hvc_beat_put_chars(uint32_t vtermno, const char *buf, int cnt)
+{
+       unsigned long kb[2];
+       int rest, nlen;
+
+       for (rest = cnt; rest > 0; rest -= nlen) {
+               nlen = (rest > 16) ? 16 : rest;
+               memcpy(kb, buf, nlen);
+               beat_put_term_char(vtermno, nlen, kb[0], kb[1]);
+               buf += nlen;
+       }
+       return cnt;
+}
+
+static const struct hv_ops hvc_beat_get_put_ops = {
+       .get_chars = hvc_beat_get_chars,
+       .put_chars = hvc_beat_put_chars,
+};
+
+static int hvc_beat_useit = 1;
+
+static int hvc_beat_config(char *p)
+{
+       hvc_beat_useit = simple_strtoul(p, NULL, 0);
+       return 0;
+}
+
+static int __init hvc_beat_console_init(void)
+{
+       if (hvc_beat_useit && of_machine_is_compatible("Beat")) {
+               hvc_instantiate(0, 0, &hvc_beat_get_put_ops);
+       }
+       return 0;
+}
+
+/* temp */
+static int __init hvc_beat_init(void)
+{
+       struct hvc_struct *hp;
+
+       if (!firmware_has_feature(FW_FEATURE_BEAT))
+               return -ENODEV;
+
+       hp = hvc_alloc(0, NO_IRQ, &hvc_beat_get_put_ops, 16);
+       if (IS_ERR(hp))
+               return PTR_ERR(hp);
+       hvc_beat_dev = hp;
+       return 0;
+}
+
+static void __exit hvc_beat_exit(void)
+{
+       if (hvc_beat_dev)
+               hvc_remove(hvc_beat_dev);
+}
+
+module_init(hvc_beat_init);
+module_exit(hvc_beat_exit);
+
+__setup("hvc_beat=", hvc_beat_config);
+
+console_initcall(hvc_beat_console_init);
diff --git a/drivers/tty/hvc/hvc_console.c b/drivers/tty/hvc/hvc_console.c
new file mode 100644 (file)
index 0000000..e9cba13
--- /dev/null
@@ -0,0 +1,914 @@
+/*
+ * Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM
+ * Copyright (C) 2001 Paul Mackerras <paulus@au.ibm.com>, IBM
+ * Copyright (C) 2004 Benjamin Herrenschmidt <benh@kernel.crashing.org>, IBM Corp.
+ * Copyright (C) 2004 IBM Corporation
+ *
+ * Additional Author(s):
+ *  Ryan S. Arnold <rsa@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ */
+
+#include <linux/console.h>
+#include <linux/cpumask.h>
+#include <linux/init.h>
+#include <linux/kbd_kern.h>
+#include <linux/kernel.h>
+#include <linux/kthread.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/major.h>
+#include <linux/sysrq.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <linux/sched.h>
+#include <linux/spinlock.h>
+#include <linux/delay.h>
+#include <linux/freezer.h>
+#include <linux/slab.h>
+
+#include <asm/uaccess.h>
+
+#include "hvc_console.h"
+
+#define HVC_MAJOR      229
+#define HVC_MINOR      0
+
+/*
+ * Wait this long per iteration while trying to push buffered data to the
+ * hypervisor before allowing the tty to complete a close operation.
+ */
+#define HVC_CLOSE_WAIT (HZ/100) /* 1/10 of a second */
+
+/*
+ * These sizes are most efficient for vio, because they are the
+ * native transfer size. We could make them selectable in the
+ * future to better deal with backends that want other buffer sizes.
+ */
+#define N_OUTBUF       16
+#define N_INBUF                16
+
+#define __ALIGNED__ __attribute__((__aligned__(sizeof(long))))
+
+static struct tty_driver *hvc_driver;
+static struct task_struct *hvc_task;
+
+/* Picks up late kicks after list walk but before schedule() */
+static int hvc_kicked;
+
+static int hvc_init(void);
+
+#ifdef CONFIG_MAGIC_SYSRQ
+static int sysrq_pressed;
+#endif
+
+/* dynamic list of hvc_struct instances */
+static LIST_HEAD(hvc_structs);
+
+/*
+ * Protect the list of hvc_struct instances from inserts and removals during
+ * list traversal.
+ */
+static DEFINE_SPINLOCK(hvc_structs_lock);
+
+/*
+ * This value is used to assign a tty->index value to a hvc_struct based
+ * upon order of exposure via hvc_probe(), when we can not match it to
+ * a console candidate registered with hvc_instantiate().
+ */
+static int last_hvc = -1;
+
+/*
+ * Do not call this function with either the hvc_structs_lock or the hvc_struct
+ * lock held.  If successful, this function increments the kref reference
+ * count against the target hvc_struct so it should be released when finished.
+ */
+static struct hvc_struct *hvc_get_by_index(int index)
+{
+       struct hvc_struct *hp;
+       unsigned long flags;
+
+       spin_lock(&hvc_structs_lock);
+
+       list_for_each_entry(hp, &hvc_structs, next) {
+               spin_lock_irqsave(&hp->lock, flags);
+               if (hp->index == index) {
+                       kref_get(&hp->kref);
+                       spin_unlock_irqrestore(&hp->lock, flags);
+                       spin_unlock(&hvc_structs_lock);
+                       return hp;
+               }
+               spin_unlock_irqrestore(&hp->lock, flags);
+       }
+       hp = NULL;
+
+       spin_unlock(&hvc_structs_lock);
+       return hp;
+}
+
+
+/*
+ * Initial console vtermnos for console API usage prior to full console
+ * initialization.  Any vty adapter outside this range will not have usable
+ * console interfaces but can still be used as a tty device.  This has to be
+ * static because kmalloc will not work during early console init.
+ */
+static const struct hv_ops *cons_ops[MAX_NR_HVC_CONSOLES];
+static uint32_t vtermnos[MAX_NR_HVC_CONSOLES] =
+       {[0 ... MAX_NR_HVC_CONSOLES - 1] = -1};
+
+/*
+ * Console APIs, NOT TTY.  These APIs are available immediately when
+ * hvc_console_setup() finds adapters.
+ */
+
+static void hvc_console_print(struct console *co, const char *b,
+                             unsigned count)
+{
+       char c[N_OUTBUF] __ALIGNED__;
+       unsigned i = 0, n = 0;
+       int r, donecr = 0, index = co->index;
+
+       /* Console access attempt outside of acceptable console range. */
+       if (index >= MAX_NR_HVC_CONSOLES)
+               return;
+
+       /* This console adapter was removed so it is not usable. */
+       if (vtermnos[index] == -1)
+               return;
+
+       while (count > 0 || i > 0) {
+               if (count > 0 && i < sizeof(c)) {
+                       if (b[n] == '\n' && !donecr) {
+                               c[i++] = '\r';
+                               donecr = 1;
+                       } else {
+                               c[i++] = b[n++];
+                               donecr = 0;
+                               --count;
+                       }
+               } else {
+                       r = cons_ops[index]->put_chars(vtermnos[index], c, i);
+                       if (r <= 0) {
+                               /* throw away chars on error */
+                               i = 0;
+                       } else if (r > 0) {
+                               i -= r;
+                               if (i > 0)
+                                       memmove(c, c+r, i);
+                       }
+               }
+       }
+}
+
+static struct tty_driver *hvc_console_device(struct console *c, int *index)
+{
+       if (vtermnos[c->index] == -1)
+               return NULL;
+
+       *index = c->index;
+       return hvc_driver;
+}
+
+static int __init hvc_console_setup(struct console *co, char *options)
+{
+       if (co->index < 0 || co->index >= MAX_NR_HVC_CONSOLES)
+               return -ENODEV;
+
+       if (vtermnos[co->index] == -1)
+               return -ENODEV;
+
+       return 0;
+}
+
+static struct console hvc_console = {
+       .name           = "hvc",
+       .write          = hvc_console_print,
+       .device         = hvc_console_device,
+       .setup          = hvc_console_setup,
+       .flags          = CON_PRINTBUFFER,
+       .index          = -1,
+};
+
+/*
+ * Early console initialization.  Precedes driver initialization.
+ *
+ * (1) we are first, and the user specified another driver
+ * -- index will remain -1
+ * (2) we are first and the user specified no driver
+ * -- index will be set to 0, then we will fail setup.
+ * (3)  we are first and the user specified our driver
+ * -- index will be set to user specified driver, and we will fail
+ * (4) we are after driver, and this initcall will register us
+ * -- if the user didn't specify a driver then the console will match
+ *
+ * Note that for cases 2 and 3, we will match later when the io driver
+ * calls hvc_instantiate() and call register again.
+ */
+static int __init hvc_console_init(void)
+{
+       register_console(&hvc_console);
+       return 0;
+}
+console_initcall(hvc_console_init);
+
+/* callback when the kboject ref count reaches zero. */
+static void destroy_hvc_struct(struct kref *kref)
+{
+       struct hvc_struct *hp = container_of(kref, struct hvc_struct, kref);
+       unsigned long flags;
+
+       spin_lock(&hvc_structs_lock);
+
+       spin_lock_irqsave(&hp->lock, flags);
+       list_del(&(hp->next));
+       spin_unlock_irqrestore(&hp->lock, flags);
+
+       spin_unlock(&hvc_structs_lock);
+
+       kfree(hp);
+}
+
+/*
+ * hvc_instantiate() is an early console discovery method which locates
+ * consoles * prior to the vio subsystem discovering them.  Hotplugged
+ * vty adapters do NOT get an hvc_instantiate() callback since they
+ * appear after early console init.
+ */
+int hvc_instantiate(uint32_t vtermno, int index, const struct hv_ops *ops)
+{
+       struct hvc_struct *hp;
+
+       if (index < 0 || index >= MAX_NR_HVC_CONSOLES)
+               return -1;
+
+       if (vtermnos[index] != -1)
+               return -1;
+
+       /* make sure no no tty has been registered in this index */
+       hp = hvc_get_by_index(index);
+       if (hp) {
+               kref_put(&hp->kref, destroy_hvc_struct);
+               return -1;
+       }
+
+       vtermnos[index] = vtermno;
+       cons_ops[index] = ops;
+
+       /* reserve all indices up to and including this index */
+       if (last_hvc < index)
+               last_hvc = index;
+
+       /* if this index is what the user requested, then register
+        * now (setup won't fail at this point).  It's ok to just
+        * call register again if previously .setup failed.
+        */
+       if (index == hvc_console.index)
+               register_console(&hvc_console);
+
+       return 0;
+}
+EXPORT_SYMBOL_GPL(hvc_instantiate);
+
+/* Wake the sleeping khvcd */
+void hvc_kick(void)
+{
+       hvc_kicked = 1;
+       wake_up_process(hvc_task);
+}
+EXPORT_SYMBOL_GPL(hvc_kick);
+
+static void hvc_unthrottle(struct tty_struct *tty)
+{
+       hvc_kick();
+}
+
+/*
+ * The TTY interface won't be used until after the vio layer has exposed the vty
+ * adapter to the kernel.
+ */
+static int hvc_open(struct tty_struct *tty, struct file * filp)
+{
+       struct hvc_struct *hp;
+       unsigned long flags;
+       int rc = 0;
+
+       /* Auto increments kref reference if found. */
+       if (!(hp = hvc_get_by_index(tty->index)))
+               return -ENODEV;
+
+       spin_lock_irqsave(&hp->lock, flags);
+       /* Check and then increment for fast path open. */
+       if (hp->count++ > 0) {
+               tty_kref_get(tty);
+               spin_unlock_irqrestore(&hp->lock, flags);
+               hvc_kick();
+               return 0;
+       } /* else count == 0 */
+
+       tty->driver_data = hp;
+
+       hp->tty = tty_kref_get(tty);
+
+       spin_unlock_irqrestore(&hp->lock, flags);
+
+       if (hp->ops->notifier_add)
+               rc = hp->ops->notifier_add(hp, hp->data);
+
+       /*
+        * If the notifier fails we return an error.  The tty layer
+        * will call hvc_close() after a failed open but we don't want to clean
+        * up there so we'll clean up here and clear out the previously set
+        * tty fields and return the kref reference.
+        */
+       if (rc) {
+               spin_lock_irqsave(&hp->lock, flags);
+               hp->tty = NULL;
+               spin_unlock_irqrestore(&hp->lock, flags);
+               tty_kref_put(tty);
+               tty->driver_data = NULL;
+               kref_put(&hp->kref, destroy_hvc_struct);
+               printk(KERN_ERR "hvc_open: request_irq failed with rc %d.\n", rc);
+       }
+       /* Force wakeup of the polling thread */
+       hvc_kick();
+
+       return rc;
+}
+
+static void hvc_close(struct tty_struct *tty, struct file * filp)
+{
+       struct hvc_struct *hp;
+       unsigned long flags;
+
+       if (tty_hung_up_p(filp))
+               return;
+
+       /*
+        * No driver_data means that this close was issued after a failed
+        * hvc_open by the tty layer's release_dev() function and we can just
+        * exit cleanly because the kref reference wasn't made.
+        */
+       if (!tty->driver_data)
+               return;
+
+       hp = tty->driver_data;
+
+       spin_lock_irqsave(&hp->lock, flags);
+
+       if (--hp->count == 0) {
+               /* We are done with the tty pointer now. */
+               hp->tty = NULL;
+               spin_unlock_irqrestore(&hp->lock, flags);
+
+               if (hp->ops->notifier_del)
+                       hp->ops->notifier_del(hp, hp->data);
+
+               /* cancel pending tty resize work */
+               cancel_work_sync(&hp->tty_resize);
+
+               /*
+                * Chain calls chars_in_buffer() and returns immediately if
+                * there is no buffered data otherwise sleeps on a wait queue
+                * waking periodically to check chars_in_buffer().
+                */
+               tty_wait_until_sent(tty, HVC_CLOSE_WAIT);
+       } else {
+               if (hp->count < 0)
+                       printk(KERN_ERR "hvc_close %X: oops, count is %d\n",
+                               hp->vtermno, hp->count);
+               spin_unlock_irqrestore(&hp->lock, flags);
+       }
+
+       tty_kref_put(tty);
+       kref_put(&hp->kref, destroy_hvc_struct);
+}
+
+static void hvc_hangup(struct tty_struct *tty)
+{
+       struct hvc_struct *hp = tty->driver_data;
+       unsigned long flags;
+       int temp_open_count;
+
+       if (!hp)
+               return;
+
+       /* cancel pending tty resize work */
+       cancel_work_sync(&hp->tty_resize);
+
+       spin_lock_irqsave(&hp->lock, flags);
+
+       /*
+        * The N_TTY line discipline has problems such that in a close vs
+        * open->hangup case this can be called after the final close so prevent
+        * that from happening for now.
+        */
+       if (hp->count <= 0) {
+               spin_unlock_irqrestore(&hp->lock, flags);
+               return;
+       }
+
+       temp_open_count = hp->count;
+       hp->count = 0;
+       hp->n_outbuf = 0;
+       hp->tty = NULL;
+
+       spin_unlock_irqrestore(&hp->lock, flags);
+
+       if (hp->ops->notifier_hangup)
+               hp->ops->notifier_hangup(hp, hp->data);
+
+       while(temp_open_count) {
+               --temp_open_count;
+               tty_kref_put(tty);
+               kref_put(&hp->kref, destroy_hvc_struct);
+       }
+}
+
+/*
+ * Push buffered characters whether they were just recently buffered or waiting
+ * on a blocked hypervisor.  Call this function with hp->lock held.
+ */
+static int hvc_push(struct hvc_struct *hp)
+{
+       int n;
+
+       n = hp->ops->put_chars(hp->vtermno, hp->outbuf, hp->n_outbuf);
+       if (n <= 0) {
+               if (n == 0) {
+                       hp->do_wakeup = 1;
+                       return 0;
+               }
+               /* throw away output on error; this happens when
+                  there is no session connected to the vterm. */
+               hp->n_outbuf = 0;
+       } else
+               hp->n_outbuf -= n;
+       if (hp->n_outbuf > 0)
+               memmove(hp->outbuf, hp->outbuf + n, hp->n_outbuf);
+       else
+               hp->do_wakeup = 1;
+
+       return n;
+}
+
+static int hvc_write(struct tty_struct *tty, const unsigned char *buf, int count)
+{
+       struct hvc_struct *hp = tty->driver_data;
+       unsigned long flags;
+       int rsize, written = 0;
+
+       /* This write was probably executed during a tty close. */
+       if (!hp)
+               return -EPIPE;
+
+       if (hp->count <= 0)
+               return -EIO;
+
+       spin_lock_irqsave(&hp->lock, flags);
+
+       /* Push pending writes */
+       if (hp->n_outbuf > 0)
+               hvc_push(hp);
+
+       while (count > 0 && (rsize = hp->outbuf_size - hp->n_outbuf) > 0) {
+               if (rsize > count)
+                       rsize = count;
+               memcpy(hp->outbuf + hp->n_outbuf, buf, rsize);
+               count -= rsize;
+               buf += rsize;
+               hp->n_outbuf += rsize;
+               written += rsize;
+               hvc_push(hp);
+       }
+       spin_unlock_irqrestore(&hp->lock, flags);
+
+       /*
+        * Racy, but harmless, kick thread if there is still pending data.
+        */
+       if (hp->n_outbuf)
+               hvc_kick();
+
+       return written;
+}
+
+/**
+ * hvc_set_winsz() - Resize the hvc tty terminal window.
+ * @work:      work structure.
+ *
+ * The routine shall not be called within an atomic context because it
+ * might sleep.
+ *
+ * Locking:    hp->lock
+ */
+static void hvc_set_winsz(struct work_struct *work)
+{
+       struct hvc_struct *hp;
+       unsigned long hvc_flags;
+       struct tty_struct *tty;
+       struct winsize ws;
+
+       hp = container_of(work, struct hvc_struct, tty_resize);
+
+       spin_lock_irqsave(&hp->lock, hvc_flags);
+       if (!hp->tty) {
+               spin_unlock_irqrestore(&hp->lock, hvc_flags);
+               return;
+       }
+       ws  = hp->ws;
+       tty = tty_kref_get(hp->tty);
+       spin_unlock_irqrestore(&hp->lock, hvc_flags);
+
+       tty_do_resize(tty, &ws);
+       tty_kref_put(tty);
+}
+
+/*
+ * This is actually a contract between the driver and the tty layer outlining
+ * how much write room the driver can guarantee will be sent OR BUFFERED.  This
+ * driver MUST honor the return value.
+ */
+static int hvc_write_room(struct tty_struct *tty)
+{
+       struct hvc_struct *hp = tty->driver_data;
+
+       if (!hp)
+               return -1;
+
+       return hp->outbuf_size - hp->n_outbuf;
+}
+
+static int hvc_chars_in_buffer(struct tty_struct *tty)
+{
+       struct hvc_struct *hp = tty->driver_data;
+
+       if (!hp)
+               return 0;
+       return hp->n_outbuf;
+}
+
+/*
+ * timeout will vary between the MIN and MAX values defined here.  By default
+ * and during console activity we will use a default MIN_TIMEOUT of 10.  When
+ * the console is idle, we increase the timeout value on each pass through
+ * msleep until we reach the max.  This may be noticeable as a brief (average
+ * one second) delay on the console before the console responds to input when
+ * there has been no input for some time.
+ */
+#define MIN_TIMEOUT            (10)
+#define MAX_TIMEOUT            (2000)
+static u32 timeout = MIN_TIMEOUT;
+
+#define HVC_POLL_READ  0x00000001
+#define HVC_POLL_WRITE 0x00000002
+
+int hvc_poll(struct hvc_struct *hp)
+{
+       struct tty_struct *tty;
+       int i, n, poll_mask = 0;
+       char buf[N_INBUF] __ALIGNED__;
+       unsigned long flags;
+       int read_total = 0;
+       int written_total = 0;
+
+       spin_lock_irqsave(&hp->lock, flags);
+
+       /* Push pending writes */
+       if (hp->n_outbuf > 0)
+               written_total = hvc_push(hp);
+
+       /* Reschedule us if still some write pending */
+       if (hp->n_outbuf > 0) {
+               poll_mask |= HVC_POLL_WRITE;
+               /* If hvc_push() was not able to write, sleep a few msecs */
+               timeout = (written_total) ? 0 : MIN_TIMEOUT;
+       }
+
+       /* No tty attached, just skip */
+       tty = tty_kref_get(hp->tty);
+       if (tty == NULL)
+               goto bail;
+
+       /* Now check if we can get data (are we throttled ?) */
+       if (test_bit(TTY_THROTTLED, &tty->flags))
+               goto throttled;
+
+       /* If we aren't notifier driven and aren't throttled, we always
+        * request a reschedule
+        */
+       if (!hp->irq_requested)
+               poll_mask |= HVC_POLL_READ;
+
+       /* Read data if any */
+       for (;;) {
+               int count = tty_buffer_request_room(tty, N_INBUF);
+
+               /* If flip is full, just reschedule a later read */
+               if (count == 0) {
+                       poll_mask |= HVC_POLL_READ;
+                       break;
+               }
+
+               n = hp->ops->get_chars(hp->vtermno, buf, count);
+               if (n <= 0) {
+                       /* Hangup the tty when disconnected from host */
+                       if (n == -EPIPE) {
+                               spin_unlock_irqrestore(&hp->lock, flags);
+                               tty_hangup(tty);
+                               spin_lock_irqsave(&hp->lock, flags);
+                       } else if ( n == -EAGAIN ) {
+                               /*
+                                * Some back-ends can only ensure a certain min
+                                * num of bytes read, which may be > 'count'.
+                                * Let the tty clear the flip buff to make room.
+                                */
+                               poll_mask |= HVC_POLL_READ;
+                       }
+                       break;
+               }
+               for (i = 0; i < n; ++i) {
+#ifdef CONFIG_MAGIC_SYSRQ
+                       if (hp->index == hvc_console.index) {
+                               /* Handle the SysRq Hack */
+                               /* XXX should support a sequence */
+                               if (buf[i] == '\x0f') { /* ^O */
+                                       /* if ^O is pressed again, reset
+                                        * sysrq_pressed and flip ^O char */
+                                       sysrq_pressed = !sysrq_pressed;
+                                       if (sysrq_pressed)
+                                               continue;
+                               } else if (sysrq_pressed) {
+                                       handle_sysrq(buf[i]);
+                                       sysrq_pressed = 0;
+                                       continue;
+                               }
+                       }
+#endif /* CONFIG_MAGIC_SYSRQ */
+                       tty_insert_flip_char(tty, buf[i], 0);
+               }
+
+               read_total += n;
+       }
+ throttled:
+       /* Wakeup write queue if necessary */
+       if (hp->do_wakeup) {
+               hp->do_wakeup = 0;
+               tty_wakeup(tty);
+       }
+ bail:
+       spin_unlock_irqrestore(&hp->lock, flags);
+
+       if (read_total) {
+               /* Activity is occurring, so reset the polling backoff value to
+                  a minimum for performance. */
+               timeout = MIN_TIMEOUT;
+
+               tty_flip_buffer_push(tty);
+       }
+       if (tty)
+               tty_kref_put(tty);
+
+       return poll_mask;
+}
+EXPORT_SYMBOL_GPL(hvc_poll);
+
+/**
+ * __hvc_resize() - Update terminal window size information.
+ * @hp:                HVC console pointer
+ * @ws:                Terminal window size structure
+ *
+ * Stores the specified window size information in the hvc structure of @hp.
+ * The function schedule the tty resize update.
+ *
+ * Locking:    Locking free; the function MUST be called holding hp->lock
+ */
+void __hvc_resize(struct hvc_struct *hp, struct winsize ws)
+{
+       hp->ws = ws;
+       schedule_work(&hp->tty_resize);
+}
+EXPORT_SYMBOL_GPL(__hvc_resize);
+
+/*
+ * This kthread is either polling or interrupt driven.  This is determined by
+ * calling hvc_poll() who determines whether a console adapter support
+ * interrupts.
+ */
+static int khvcd(void *unused)
+{
+       int poll_mask;
+       struct hvc_struct *hp;
+
+       set_freezable();
+       do {
+               poll_mask = 0;
+               hvc_kicked = 0;
+               try_to_freeze();
+               wmb();
+               if (!cpus_are_in_xmon()) {
+                       spin_lock(&hvc_structs_lock);
+                       list_for_each_entry(hp, &hvc_structs, next) {
+                               poll_mask |= hvc_poll(hp);
+                       }
+                       spin_unlock(&hvc_structs_lock);
+               } else
+                       poll_mask |= HVC_POLL_READ;
+               if (hvc_kicked)
+                       continue;
+               set_current_state(TASK_INTERRUPTIBLE);
+               if (!hvc_kicked) {
+                       if (poll_mask == 0)
+                               schedule();
+                       else {
+                               if (timeout < MAX_TIMEOUT)
+                                       timeout += (timeout >> 6) + 1;
+
+                               msleep_interruptible(timeout);
+                       }
+               }
+               __set_current_state(TASK_RUNNING);
+       } while (!kthread_should_stop());
+
+       return 0;
+}
+
+static const struct tty_operations hvc_ops = {
+       .open = hvc_open,
+       .close = hvc_close,
+       .write = hvc_write,
+       .hangup = hvc_hangup,
+       .unthrottle = hvc_unthrottle,
+       .write_room = hvc_write_room,
+       .chars_in_buffer = hvc_chars_in_buffer,
+};
+
+struct hvc_struct *hvc_alloc(uint32_t vtermno, int data,
+                            const struct hv_ops *ops,
+                            int outbuf_size)
+{
+       struct hvc_struct *hp;
+       int i;
+
+       /* We wait until a driver actually comes along */
+       if (!hvc_driver) {
+               int err = hvc_init();
+               if (err)
+                       return ERR_PTR(err);
+       }
+
+       hp = kzalloc(ALIGN(sizeof(*hp), sizeof(long)) + outbuf_size,
+                       GFP_KERNEL);
+       if (!hp)
+               return ERR_PTR(-ENOMEM);
+
+       hp->vtermno = vtermno;
+       hp->data = data;
+       hp->ops = ops;
+       hp->outbuf_size = outbuf_size;
+       hp->outbuf = &((char *)hp)[ALIGN(sizeof(*hp), sizeof(long))];
+
+       kref_init(&hp->kref);
+
+       INIT_WORK(&hp->tty_resize, hvc_set_winsz);
+       spin_lock_init(&hp->lock);
+       spin_lock(&hvc_structs_lock);
+
+       /*
+        * find index to use:
+        * see if this vterm id matches one registered for console.
+        */
+       for (i=0; i < MAX_NR_HVC_CONSOLES; i++)
+               if (vtermnos[i] == hp->vtermno &&
+                   cons_ops[i] == hp->ops)
+                       break;
+
+       /* no matching slot, just use a counter */
+       if (i >= MAX_NR_HVC_CONSOLES)
+               i = ++last_hvc;
+
+       hp->index = i;
+
+       list_add_tail(&(hp->next), &hvc_structs);
+       spin_unlock(&hvc_structs_lock);
+
+       return hp;
+}
+EXPORT_SYMBOL_GPL(hvc_alloc);
+
+int hvc_remove(struct hvc_struct *hp)
+{
+       unsigned long flags;
+       struct tty_struct *tty;
+
+       spin_lock_irqsave(&hp->lock, flags);
+       tty = tty_kref_get(hp->tty);
+
+       if (hp->index < MAX_NR_HVC_CONSOLES)
+               vtermnos[hp->index] = -1;
+
+       /* Don't whack hp->irq because tty_hangup() will need to free the irq. */
+
+       spin_unlock_irqrestore(&hp->lock, flags);
+
+       /*
+        * We 'put' the instance that was grabbed when the kref instance
+        * was initialized using kref_init().  Let the last holder of this
+        * kref cause it to be removed, which will probably be the tty_vhangup
+        * below.
+        */
+       kref_put(&hp->kref, destroy_hvc_struct);
+
+       /*
+        * This function call will auto chain call hvc_hangup.
+        */
+       if (tty) {
+               tty_vhangup(tty);
+               tty_kref_put(tty);
+       }
+       return 0;
+}
+EXPORT_SYMBOL_GPL(hvc_remove);
+
+/* Driver initialization: called as soon as someone uses hvc_alloc(). */
+static int hvc_init(void)
+{
+       struct tty_driver *drv;
+       int err;
+
+       /* We need more than hvc_count adapters due to hotplug additions. */
+       drv = alloc_tty_driver(HVC_ALLOC_TTY_ADAPTERS);
+       if (!drv) {
+               err = -ENOMEM;
+               goto out;
+       }
+
+       drv->owner = THIS_MODULE;
+       drv->driver_name = "hvc";
+       drv->name = "hvc";
+       drv->major = HVC_MAJOR;
+       drv->minor_start = HVC_MINOR;
+       drv->type = TTY_DRIVER_TYPE_SYSTEM;
+       drv->init_termios = tty_std_termios;
+       drv->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_RESET_TERMIOS;
+       tty_set_operations(drv, &hvc_ops);
+
+       /* Always start the kthread because there can be hotplug vty adapters
+        * added later. */
+       hvc_task = kthread_run(khvcd, NULL, "khvcd");
+       if (IS_ERR(hvc_task)) {
+               printk(KERN_ERR "Couldn't create kthread for console.\n");
+               err = PTR_ERR(hvc_task);
+               goto put_tty;
+       }
+
+       err = tty_register_driver(drv);
+       if (err) {
+               printk(KERN_ERR "Couldn't register hvc console driver\n");
+               goto stop_thread;
+       }
+
+       /*
+        * Make sure tty is fully registered before allowing it to be
+        * found by hvc_console_device.
+        */
+       smp_mb();
+       hvc_driver = drv;
+       return 0;
+
+stop_thread:
+       kthread_stop(hvc_task);
+       hvc_task = NULL;
+put_tty:
+       put_tty_driver(drv);
+out:
+       return err;
+}
+
+/* This isn't particularly necessary due to this being a console driver
+ * but it is nice to be thorough.
+ */
+static void __exit hvc_exit(void)
+{
+       if (hvc_driver) {
+               kthread_stop(hvc_task);
+
+               tty_unregister_driver(hvc_driver);
+               /* return tty_struct instances allocated in hvc_init(). */
+               put_tty_driver(hvc_driver);
+               unregister_console(&hvc_console);
+       }
+}
+module_exit(hvc_exit);
diff --git a/drivers/tty/hvc/hvc_console.h b/drivers/tty/hvc/hvc_console.h
new file mode 100644 (file)
index 0000000..54381eb
--- /dev/null
@@ -0,0 +1,119 @@
+/*
+ * hvc_console.h
+ * Copyright (C) 2005 IBM Corporation
+ *
+ * Author(s):
+ *     Ryan S. Arnold <rsa@us.ibm.com>
+ *
+ * hvc_console header information:
+ *      moved here from arch/powerpc/include/asm/hvconsole.h
+ *      and drivers/char/hvc_console.c
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ */
+
+#ifndef HVC_CONSOLE_H
+#define HVC_CONSOLE_H
+#include <linux/kref.h>
+#include <linux/tty.h>
+#include <linux/spinlock.h>
+
+/*
+ * This is the max number of console adapters that can/will be found as
+ * console devices on first stage console init.  Any number beyond this range
+ * can't be used as a console device but is still a valid tty device.
+ */
+#define MAX_NR_HVC_CONSOLES    16
+
+/*
+ * The Linux TTY code does not support dynamic addition of tty derived devices
+ * so we need to know how many tty devices we might need when space is allocated
+ * for the tty device.  Since this driver supports hotplug of vty adapters we
+ * need to make sure we have enough allocated.
+ */
+#define HVC_ALLOC_TTY_ADAPTERS 8
+
+struct hvc_struct {
+       spinlock_t lock;
+       int index;
+       struct tty_struct *tty;
+       int count;
+       int do_wakeup;
+       char *outbuf;
+       int outbuf_size;
+       int n_outbuf;
+       uint32_t vtermno;
+       const struct hv_ops *ops;
+       int irq_requested;
+       int data;
+       struct winsize ws;
+       struct work_struct tty_resize;
+       struct list_head next;
+       struct kref kref; /* ref count & hvc_struct lifetime */
+};
+
+/* implemented by a low level driver */
+struct hv_ops {
+       int (*get_chars)(uint32_t vtermno, char *buf, int count);
+       int (*put_chars)(uint32_t vtermno, const char *buf, int count);
+
+       /* Callbacks for notification. Called in open, close and hangup */
+       int (*notifier_add)(struct hvc_struct *hp, int irq);
+       void (*notifier_del)(struct hvc_struct *hp, int irq);
+       void (*notifier_hangup)(struct hvc_struct *hp, int irq);
+};
+
+/* Register a vterm and a slot index for use as a console (console_init) */
+extern int hvc_instantiate(uint32_t vtermno, int index,
+                          const struct hv_ops *ops);
+
+/* register a vterm for hvc tty operation (module_init or hotplug add) */
+extern struct hvc_struct * hvc_alloc(uint32_t vtermno, int data,
+                                    const struct hv_ops *ops, int outbuf_size);
+/* remove a vterm from hvc tty operation (module_exit or hotplug remove) */
+extern int hvc_remove(struct hvc_struct *hp);
+
+/* data available */
+int hvc_poll(struct hvc_struct *hp);
+void hvc_kick(void);
+
+/* Resize hvc tty terminal window */
+extern void __hvc_resize(struct hvc_struct *hp, struct winsize ws);
+
+static inline void hvc_resize(struct hvc_struct *hp, struct winsize ws)
+{
+       unsigned long flags;
+
+       spin_lock_irqsave(&hp->lock, flags);
+       __hvc_resize(hp, ws);
+       spin_unlock_irqrestore(&hp->lock, flags);
+}
+
+/* default notifier for irq based notification */
+extern int notifier_add_irq(struct hvc_struct *hp, int data);
+extern void notifier_del_irq(struct hvc_struct *hp, int data);
+extern void notifier_hangup_irq(struct hvc_struct *hp, int data);
+
+
+#if defined(CONFIG_XMON) && defined(CONFIG_SMP)
+#include <asm/xmon.h>
+#else
+static inline int cpus_are_in_xmon(void)
+{
+       return 0;
+}
+#endif
+
+#endif // HVC_CONSOLE_H
diff --git a/drivers/tty/hvc/hvc_dcc.c b/drivers/tty/hvc/hvc_dcc.c
new file mode 100644 (file)
index 0000000..6470f63
--- /dev/null
@@ -0,0 +1,133 @@
+/* Copyright (c) 2010, Code Aurora Forum. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+#include <linux/console.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/moduleparam.h>
+#include <linux/types.h>
+
+#include <asm/processor.h>
+
+#include "hvc_console.h"
+
+/* DCC Status Bits */
+#define DCC_STATUS_RX          (1 << 30)
+#define DCC_STATUS_TX          (1 << 29)
+
+static inline u32 __dcc_getstatus(void)
+{
+       u32 __ret;
+
+       asm("mrc p14, 0, %0, c0, c1, 0  @ read comms ctrl reg"
+               : "=r" (__ret) : : "cc");
+
+       return __ret;
+}
+
+
+#if defined(CONFIG_CPU_V7)
+static inline char __dcc_getchar(void)
+{
+       char __c;
+
+       asm("get_wait:  mrc p14, 0, pc, c0, c1, 0                          \n\
+                       bne get_wait                                       \n\
+                       mrc p14, 0, %0, c0, c5, 0       @ read comms data reg"
+               : "=r" (__c) : : "cc");
+
+       return __c;
+}
+#else
+static inline char __dcc_getchar(void)
+{
+       char __c;
+
+       asm("mrc p14, 0, %0, c0, c5, 0  @ read comms data reg"
+               : "=r" (__c));
+
+       return __c;
+}
+#endif
+
+#if defined(CONFIG_CPU_V7)
+static inline void __dcc_putchar(char c)
+{
+       asm("put_wait:  mrc p14, 0, pc, c0, c1, 0                 \n\
+                       bcs put_wait                              \n\
+                       mcr p14, 0, %0, c0, c5, 0                   "
+       : : "r" (c) : "cc");
+}
+#else
+static inline void __dcc_putchar(char c)
+{
+       asm("mcr p14, 0, %0, c0, c5, 0  @ write a char"
+               : /* no output register */
+               : "r" (c));
+}
+#endif
+
+static int hvc_dcc_put_chars(uint32_t vt, const char *buf, int count)
+{
+       int i;
+
+       for (i = 0; i < count; i++) {
+               while (__dcc_getstatus() & DCC_STATUS_TX)
+                       cpu_relax();
+
+               __dcc_putchar((char)(buf[i] & 0xFF));
+       }
+
+       return count;
+}
+
+static int hvc_dcc_get_chars(uint32_t vt, char *buf, int count)
+{
+       int i;
+
+       for (i = 0; i < count; ++i) {
+               int c = -1;
+
+               if (__dcc_getstatus() & DCC_STATUS_RX)
+                       c = __dcc_getchar();
+               if (c < 0)
+                       break;
+               buf[i] = c;
+       }
+
+       return i;
+}
+
+static const struct hv_ops hvc_dcc_get_put_ops = {
+       .get_chars = hvc_dcc_get_chars,
+       .put_chars = hvc_dcc_put_chars,
+};
+
+static int __init hvc_dcc_console_init(void)
+{
+       hvc_instantiate(0, 0, &hvc_dcc_get_put_ops);
+       return 0;
+}
+console_initcall(hvc_dcc_console_init);
+
+static int __init hvc_dcc_init(void)
+{
+       hvc_alloc(0, 0, &hvc_dcc_get_put_ops, 128);
+       return 0;
+}
+device_initcall(hvc_dcc_init);
diff --git a/drivers/tty/hvc/hvc_irq.c b/drivers/tty/hvc/hvc_irq.c
new file mode 100644 (file)
index 0000000..2623e17
--- /dev/null
@@ -0,0 +1,49 @@
+/*
+ * Copyright IBM Corp. 2001,2008
+ *
+ * This file contains the IRQ specific code for hvc_console
+ *
+ */
+
+#include <linux/interrupt.h>
+
+#include "hvc_console.h"
+
+static irqreturn_t hvc_handle_interrupt(int irq, void *dev_instance)
+{
+       /* if hvc_poll request a repoll, then kick the hvcd thread */
+       if (hvc_poll(dev_instance))
+               hvc_kick();
+       return IRQ_HANDLED;
+}
+
+/*
+ * For IRQ based systems these callbacks can be used
+ */
+int notifier_add_irq(struct hvc_struct *hp, int irq)
+{
+       int rc;
+
+       if (!irq) {
+               hp->irq_requested = 0;
+               return 0;
+       }
+       rc = request_irq(irq, hvc_handle_interrupt, IRQF_DISABLED,
+                          "hvc_console", hp);
+       if (!rc)
+               hp->irq_requested = 1;
+       return rc;
+}
+
+void notifier_del_irq(struct hvc_struct *hp, int irq)
+{
+       if (!hp->irq_requested)
+               return;
+       free_irq(irq, hp);
+       hp->irq_requested = 0;
+}
+
+void notifier_hangup_irq(struct hvc_struct *hp, int irq)
+{
+       notifier_del_irq(hp, irq);
+}
diff --git a/drivers/tty/hvc/hvc_iseries.c b/drivers/tty/hvc/hvc_iseries.c
new file mode 100644 (file)
index 0000000..21c5495
--- /dev/null
@@ -0,0 +1,598 @@
+/*
+ * iSeries vio driver interface to hvc_console.c
+ *
+ * This code is based heavily on hvc_vio.c and viocons.c
+ *
+ * Copyright (C) 2006 Stephen Rothwell, IBM Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ */
+#include <stdarg.h>
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/spinlock.h>
+#include <linux/console.h>
+
+#include <asm/hvconsole.h>
+#include <asm/vio.h>
+#include <asm/prom.h>
+#include <asm/firmware.h>
+#include <asm/iseries/vio.h>
+#include <asm/iseries/hv_call.h>
+#include <asm/iseries/hv_lp_config.h>
+#include <asm/iseries/hv_lp_event.h>
+
+#include "hvc_console.h"
+
+#define VTTY_PORTS 10
+
+static DEFINE_SPINLOCK(consolelock);
+static DEFINE_SPINLOCK(consoleloglock);
+
+static const char hvc_driver_name[] = "hvc_console";
+
+#define IN_BUF_SIZE    200
+
+/*
+ * Our port information.
+ */
+static struct port_info {
+       HvLpIndex lp;
+       u64 seq;        /* sequence number of last HV send */
+       u64 ack;        /* last ack from HV */
+       struct hvc_struct *hp;
+       int in_start;
+       int in_end;
+       unsigned char in_buf[IN_BUF_SIZE];
+} port_info[VTTY_PORTS] = {
+       [ 0 ... VTTY_PORTS - 1 ] = {
+               .lp = HvLpIndexInvalid
+       }
+};
+
+#define viochar_is_console(pi) ((pi) == &port_info[0])
+
+static struct vio_device_id hvc_driver_table[] __devinitdata = {
+       {"serial", "IBM,iSeries-vty"},
+       { "", "" }
+};
+MODULE_DEVICE_TABLE(vio, hvc_driver_table);
+
+static void hvlog(char *fmt, ...)
+{
+       int i;
+       unsigned long flags;
+       va_list args;
+       static char buf[256];
+
+       spin_lock_irqsave(&consoleloglock, flags);
+       va_start(args, fmt);
+       i = vscnprintf(buf, sizeof(buf) - 1, fmt, args);
+       va_end(args);
+       buf[i++] = '\r';
+       HvCall_writeLogBuffer(buf, i);
+       spin_unlock_irqrestore(&consoleloglock, flags);
+}
+
+/*
+ * Initialize the common fields in a charLpEvent
+ */
+static void init_data_event(struct viocharlpevent *viochar, HvLpIndex lp)
+{
+       struct HvLpEvent *hev = &viochar->event;
+
+       memset(viochar, 0, sizeof(struct viocharlpevent));
+
+       hev->flags = HV_LP_EVENT_VALID | HV_LP_EVENT_DEFERRED_ACK |
+               HV_LP_EVENT_INT;
+       hev->xType = HvLpEvent_Type_VirtualIo;
+       hev->xSubtype = viomajorsubtype_chario | viochardata;
+       hev->xSourceLp = HvLpConfig_getLpIndex();
+       hev->xTargetLp = lp;
+       hev->xSizeMinus1 = sizeof(struct viocharlpevent);
+       hev->xSourceInstanceId = viopath_sourceinst(lp);
+       hev->xTargetInstanceId = viopath_targetinst(lp);
+}
+
+static int get_chars(uint32_t vtermno, char *buf, int count)
+{
+       struct port_info *pi;
+       int n = 0;
+       unsigned long flags;
+
+       if (vtermno >= VTTY_PORTS)
+               return -EINVAL;
+       if (count == 0)
+               return 0;
+
+       pi = &port_info[vtermno];
+       spin_lock_irqsave(&consolelock, flags);
+
+       if (pi->in_end == 0)
+               goto done;
+
+       n = pi->in_end - pi->in_start;
+       if (n > count)
+               n = count;
+       memcpy(buf, &pi->in_buf[pi->in_start], n);
+       pi->in_start += n;
+       if (pi->in_start == pi->in_end) {
+               pi->in_start = 0;
+               pi->in_end = 0;
+       }
+done:
+       spin_unlock_irqrestore(&consolelock, flags);
+       return n;
+}
+
+static int put_chars(uint32_t vtermno, const char *buf, int count)
+{
+       struct viocharlpevent *viochar;
+       struct port_info *pi;
+       HvLpEvent_Rc hvrc;
+       unsigned long flags;
+       int sent = 0;
+
+       if (vtermno >= VTTY_PORTS)
+               return -EINVAL;
+
+       pi = &port_info[vtermno];
+
+       spin_lock_irqsave(&consolelock, flags);
+
+       if (viochar_is_console(pi) && !viopath_isactive(pi->lp)) {
+               HvCall_writeLogBuffer(buf, count);
+               sent = count;
+               goto done;
+       }
+
+       viochar = vio_get_event_buffer(viomajorsubtype_chario);
+       if (viochar == NULL) {
+               hvlog("\n\rviocons: Can't get viochar buffer.");
+               goto done;
+       }
+
+       while ((count > 0) && ((pi->seq - pi->ack) < VIOCHAR_WINDOW)) {
+               int len;
+
+               len = (count > VIOCHAR_MAX_DATA) ? VIOCHAR_MAX_DATA : count;
+
+               if (viochar_is_console(pi))
+                       HvCall_writeLogBuffer(buf, len);
+
+               init_data_event(viochar, pi->lp);
+
+               viochar->len = len;
+               viochar->event.xCorrelationToken = pi->seq++;
+               viochar->event.xSizeMinus1 =
+                       offsetof(struct viocharlpevent, data) + len;
+
+               memcpy(viochar->data, buf, len);
+
+               hvrc = HvCallEvent_signalLpEvent(&viochar->event);
+               if (hvrc)
+                       hvlog("\n\rerror sending event! return code %d\n\r",
+                               (int)hvrc);
+               sent += len;
+               count -= len;
+               buf += len;
+       }
+
+       vio_free_event_buffer(viomajorsubtype_chario, viochar);
+done:
+       spin_unlock_irqrestore(&consolelock, flags);
+       return sent;
+}
+
+static const struct hv_ops hvc_get_put_ops = {
+       .get_chars = get_chars,
+       .put_chars = put_chars,
+       .notifier_add = notifier_add_irq,
+       .notifier_del = notifier_del_irq,
+       .notifier_hangup = notifier_hangup_irq,
+};
+
+static int __devinit hvc_vio_probe(struct vio_dev *vdev,
+                       const struct vio_device_id *id)
+{
+       struct hvc_struct *hp;
+       struct port_info *pi;
+
+       /* probed with invalid parameters. */
+       if (!vdev || !id)
+               return -EPERM;
+
+       if (vdev->unit_address >= VTTY_PORTS)
+               return -ENODEV;
+
+       pi = &port_info[vdev->unit_address];
+
+       hp = hvc_alloc(vdev->unit_address, vdev->irq, &hvc_get_put_ops,
+                       VIOCHAR_MAX_DATA);
+       if (IS_ERR(hp))
+               return PTR_ERR(hp);
+       pi->hp = hp;
+       dev_set_drvdata(&vdev->dev, pi);
+
+       return 0;
+}
+
+static int __devexit hvc_vio_remove(struct vio_dev *vdev)
+{
+       struct port_info *pi = dev_get_drvdata(&vdev->dev);
+       struct hvc_struct *hp = pi->hp;
+
+       return hvc_remove(hp);
+}
+
+static struct vio_driver hvc_vio_driver = {
+       .id_table       = hvc_driver_table,
+       .probe          = hvc_vio_probe,
+       .remove         = __devexit_p(hvc_vio_remove),
+       .driver         = {
+               .name   = hvc_driver_name,
+               .owner  = THIS_MODULE,
+       }
+};
+
+static void hvc_open_event(struct HvLpEvent *event)
+{
+       unsigned long flags;
+       struct viocharlpevent *cevent = (struct viocharlpevent *)event;
+       u8 port = cevent->virtual_device;
+       struct port_info *pi;
+       int reject = 0;
+
+       if (hvlpevent_is_ack(event)) {
+               if (port >= VTTY_PORTS)
+                       return;
+
+               spin_lock_irqsave(&consolelock, flags);
+
+               pi = &port_info[port];
+               if (event->xRc == HvLpEvent_Rc_Good) {
+                       pi->seq = pi->ack = 0;
+                       /*
+                        * This line allows connections from the primary
+                        * partition but once one is connected from the
+                        * primary partition nothing short of a reboot
+                        * of linux will allow access from the hosting
+                        * partition again without a required iSeries fix.
+                        */
+                       pi->lp = event->xTargetLp;
+               }
+
+               spin_unlock_irqrestore(&consolelock, flags);
+               if (event->xRc != HvLpEvent_Rc_Good)
+                       printk(KERN_WARNING
+                              "hvc: handle_open_event: event->xRc == (%d).\n",
+                              event->xRc);
+
+               if (event->xCorrelationToken != 0) {
+                       atomic_t *aptr= (atomic_t *)event->xCorrelationToken;
+                       atomic_set(aptr, 1);
+               } else
+                       printk(KERN_WARNING
+                              "hvc: weird...got open ack without atomic\n");
+               return;
+       }
+
+       /* This had better require an ack, otherwise complain */
+       if (!hvlpevent_need_ack(event)) {
+               printk(KERN_WARNING "hvc: viocharopen without ack bit!\n");
+               return;
+       }
+
+       spin_lock_irqsave(&consolelock, flags);
+
+       /* Make sure this is a good virtual tty */
+       if (port >= VTTY_PORTS) {
+               event->xRc = HvLpEvent_Rc_SubtypeError;
+               cevent->subtype_result_code = viorc_openRejected;
+               /*
+                * Flag state here since we can't printk while holding
+                * the consolelock spinlock.
+                */
+               reject = 1;
+       } else {
+               pi = &port_info[port];
+               if ((pi->lp != HvLpIndexInvalid) &&
+                               (pi->lp != event->xSourceLp)) {
+                       /*
+                        * If this is tty is already connected to a different
+                        * partition, fail.
+                        */
+                       event->xRc = HvLpEvent_Rc_SubtypeError;
+                       cevent->subtype_result_code = viorc_openRejected;
+                       reject = 2;
+               } else {
+                       pi->lp = event->xSourceLp;
+                       event->xRc = HvLpEvent_Rc_Good;
+                       cevent->subtype_result_code = viorc_good;
+                       pi->seq = pi->ack = 0;
+               }
+       }
+
+       spin_unlock_irqrestore(&consolelock, flags);
+
+       if (reject == 1)
+               printk(KERN_WARNING "hvc: open rejected: bad virtual tty.\n");
+       else if (reject == 2)
+               printk(KERN_WARNING "hvc: open rejected: console in exclusive "
+                               "use by another partition.\n");
+
+       /* Return the acknowledgement */
+       HvCallEvent_ackLpEvent(event);
+}
+
+/*
+ * Handle a close charLpEvent.  This should ONLY be an Interrupt because the
+ * virtual console should never actually issue a close event to the hypervisor
+ * because the virtual console never goes away.  A close event coming from the
+ * hypervisor simply means that there are no client consoles connected to the
+ * virtual console.
+ */
+static void hvc_close_event(struct HvLpEvent *event)
+{
+       unsigned long flags;
+       struct viocharlpevent *cevent = (struct viocharlpevent *)event;
+       u8 port = cevent->virtual_device;
+
+       if (!hvlpevent_is_int(event)) {
+               printk(KERN_WARNING
+                       "hvc: got unexpected close acknowledgement\n");
+               return;
+       }
+
+       if (port >= VTTY_PORTS) {
+               printk(KERN_WARNING
+                       "hvc: close message from invalid virtual device.\n");
+               return;
+       }
+
+       /* For closes, just mark the console partition invalid */
+       spin_lock_irqsave(&consolelock, flags);
+
+       if (port_info[port].lp == event->xSourceLp)
+               port_info[port].lp = HvLpIndexInvalid;
+
+       spin_unlock_irqrestore(&consolelock, flags);
+}
+
+static void hvc_data_event(struct HvLpEvent *event)
+{
+       unsigned long flags;
+       struct viocharlpevent *cevent = (struct viocharlpevent *)event;
+       struct port_info *pi;
+       int n;
+       u8 port = cevent->virtual_device;
+
+       if (port >= VTTY_PORTS) {
+               printk(KERN_WARNING "hvc: data on invalid virtual device %d\n",
+                               port);
+               return;
+       }
+       if (cevent->len == 0)
+               return;
+
+       /*
+        * Change 05/01/2003 - Ryan Arnold: If a partition other than
+        * the current exclusive partition tries to send us data
+        * events then just drop them on the floor because we don't
+        * want his stinking data.  He isn't authorized to receive
+        * data because he wasn't the first one to get the console,
+        * therefore he shouldn't be allowed to send data either.
+        * This will work without an iSeries fix.
+        */
+       pi = &port_info[port];
+       if (pi->lp != event->xSourceLp)
+               return;
+
+       spin_lock_irqsave(&consolelock, flags);
+
+       n = IN_BUF_SIZE - pi->in_end;
+       if (n > cevent->len)
+               n = cevent->len;
+       if (n > 0) {
+               memcpy(&pi->in_buf[pi->in_end], cevent->data, n);
+               pi->in_end += n;
+       }
+       spin_unlock_irqrestore(&consolelock, flags);
+       if (n == 0)
+               printk(KERN_WARNING "hvc: input buffer overflow\n");
+}
+
+static void hvc_ack_event(struct HvLpEvent *event)
+{
+       struct viocharlpevent *cevent = (struct viocharlpevent *)event;
+       unsigned long flags;
+       u8 port = cevent->virtual_device;
+
+       if (port >= VTTY_PORTS) {
+               printk(KERN_WARNING "hvc: data on invalid virtual device\n");
+               return;
+       }
+
+       spin_lock_irqsave(&consolelock, flags);
+       port_info[port].ack = event->xCorrelationToken;
+       spin_unlock_irqrestore(&consolelock, flags);
+}
+
+static void hvc_config_event(struct HvLpEvent *event)
+{
+       struct viocharlpevent *cevent = (struct viocharlpevent *)event;
+
+       if (cevent->data[0] == 0x01)
+               printk(KERN_INFO "hvc: window resized to %d: %d: %d: %d\n",
+                      cevent->data[1], cevent->data[2],
+                      cevent->data[3], cevent->data[4]);
+       else
+               printk(KERN_WARNING "hvc: unknown config event\n");
+}
+
+static void hvc_handle_event(struct HvLpEvent *event)
+{
+       int charminor;
+
+       if (event == NULL)
+               return;
+
+       charminor = event->xSubtype & VIOMINOR_SUBTYPE_MASK;
+       switch (charminor) {
+       case viocharopen:
+               hvc_open_event(event);
+               break;
+       case viocharclose:
+               hvc_close_event(event);
+               break;
+       case viochardata:
+               hvc_data_event(event);
+               break;
+       case viocharack:
+               hvc_ack_event(event);
+               break;
+       case viocharconfig:
+               hvc_config_event(event);
+               break;
+       default:
+               if (hvlpevent_is_int(event) && hvlpevent_need_ack(event)) {
+                       event->xRc = HvLpEvent_Rc_InvalidSubtype;
+                       HvCallEvent_ackLpEvent(event);
+               }
+       }
+}
+
+static int __init send_open(HvLpIndex remoteLp, void *sem)
+{
+       return HvCallEvent_signalLpEventFast(remoteLp,
+                       HvLpEvent_Type_VirtualIo,
+                       viomajorsubtype_chario | viocharopen,
+                       HvLpEvent_AckInd_DoAck, HvLpEvent_AckType_ImmediateAck,
+                       viopath_sourceinst(remoteLp),
+                       viopath_targetinst(remoteLp),
+                       (u64)(unsigned long)sem, VIOVERSION << 16,
+                       0, 0, 0, 0);
+}
+
+static int __init hvc_vio_init(void)
+{
+       atomic_t wait_flag;
+       int rc;
+
+       if (!firmware_has_feature(FW_FEATURE_ISERIES))
+               return -EIO;
+
+       /* +2 for fudge */
+       rc = viopath_open(HvLpConfig_getPrimaryLpIndex(),
+                       viomajorsubtype_chario, VIOCHAR_WINDOW + 2);
+       if (rc)
+               printk(KERN_WARNING "hvc: error opening to primary %d\n", rc);
+
+       if (viopath_hostLp == HvLpIndexInvalid)
+               vio_set_hostlp();
+
+       /*
+        * And if the primary is not the same as the hosting LP, open to the
+        * hosting lp
+        */
+       if ((viopath_hostLp != HvLpIndexInvalid) &&
+           (viopath_hostLp != HvLpConfig_getPrimaryLpIndex())) {
+               printk(KERN_INFO "hvc: open path to hosting (%d)\n",
+                               viopath_hostLp);
+               rc = viopath_open(viopath_hostLp, viomajorsubtype_chario,
+                               VIOCHAR_WINDOW + 2);    /* +2 for fudge */
+               if (rc)
+                       printk(KERN_WARNING
+                               "error opening to partition %d: %d\n",
+                               viopath_hostLp, rc);
+       }
+
+       if (vio_setHandler(viomajorsubtype_chario, hvc_handle_event) < 0)
+               printk(KERN_WARNING
+                       "hvc: error seting handler for console events!\n");
+
+       /*
+        * First, try to open the console to the hosting lp.
+        * Wait on a semaphore for the response.
+        */
+       atomic_set(&wait_flag, 0);
+       if ((viopath_isactive(viopath_hostLp)) &&
+           (send_open(viopath_hostLp, &wait_flag) == 0)) {
+               printk(KERN_INFO "hvc: hosting partition %d\n", viopath_hostLp);
+               while (atomic_read(&wait_flag) == 0)
+                       mb();
+               atomic_set(&wait_flag, 0);
+       }
+
+       /*
+        * If we don't have an active console, try the primary
+        */
+       if ((!viopath_isactive(port_info[0].lp)) &&
+           (viopath_isactive(HvLpConfig_getPrimaryLpIndex())) &&
+           (send_open(HvLpConfig_getPrimaryLpIndex(), &wait_flag) == 0)) {
+               printk(KERN_INFO "hvc: opening console to primary partition\n");
+               while (atomic_read(&wait_flag) == 0)
+                       mb();
+       }
+
+       /* Register as a vio device to receive callbacks */
+       rc = vio_register_driver(&hvc_vio_driver);
+
+       return rc;
+}
+module_init(hvc_vio_init); /* after drivers/char/hvc_console.c */
+
+static void __exit hvc_vio_exit(void)
+{
+       vio_unregister_driver(&hvc_vio_driver);
+}
+module_exit(hvc_vio_exit);
+
+/* the device tree order defines our numbering */
+static int __init hvc_find_vtys(void)
+{
+       struct device_node *vty;
+       int num_found = 0;
+
+       for (vty = of_find_node_by_name(NULL, "vty"); vty != NULL;
+                       vty = of_find_node_by_name(vty, "vty")) {
+               const uint32_t *vtermno;
+
+               /* We have statically defined space for only a certain number
+                * of console adapters.
+                */
+               if ((num_found >= MAX_NR_HVC_CONSOLES) ||
+                               (num_found >= VTTY_PORTS)) {
+                       of_node_put(vty);
+                       break;
+               }
+
+               vtermno = of_get_property(vty, "reg", NULL);
+               if (!vtermno)
+                       continue;
+
+               if (!of_device_is_compatible(vty, "IBM,iSeries-vty"))
+                       continue;
+
+               if (num_found == 0)
+                       add_preferred_console("hvc", 0, NULL);
+               hvc_instantiate(*vtermno, num_found, &hvc_get_put_ops);
+               ++num_found;
+       }
+
+       return num_found;
+}
+console_initcall(hvc_find_vtys);
diff --git a/drivers/tty/hvc/hvc_iucv.c b/drivers/tty/hvc/hvc_iucv.c
new file mode 100644 (file)
index 0000000..c3425bb
--- /dev/null
@@ -0,0 +1,1337 @@
+/*
+ * hvc_iucv.c - z/VM IUCV hypervisor console (HVC) device driver
+ *
+ * This HVC device driver provides terminal access using
+ * z/VM IUCV communication paths.
+ *
+ * Copyright IBM Corp. 2008, 2009
+ *
+ * Author(s):  Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
+ */
+#define KMSG_COMPONENT         "hvc_iucv"
+#define pr_fmt(fmt)            KMSG_COMPONENT ": " fmt
+
+#include <linux/types.h>
+#include <linux/slab.h>
+#include <asm/ebcdic.h>
+#include <linux/ctype.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/mempool.h>
+#include <linux/moduleparam.h>
+#include <linux/tty.h>
+#include <linux/wait.h>
+#include <net/iucv/iucv.h>
+
+#include "hvc_console.h"
+
+
+/* General device driver settings */
+#define HVC_IUCV_MAGIC         0xc9e4c3e5
+#define MAX_HVC_IUCV_LINES     HVC_ALLOC_TTY_ADAPTERS
+#define MEMPOOL_MIN_NR         (PAGE_SIZE / sizeof(struct iucv_tty_buffer)/4)
+
+/* IUCV TTY message  */
+#define MSG_VERSION            0x02    /* Message version */
+#define MSG_TYPE_ERROR         0x01    /* Error message */
+#define MSG_TYPE_TERMENV       0x02    /* Terminal environment variable */
+#define MSG_TYPE_TERMIOS       0x04    /* Terminal IO struct update */
+#define MSG_TYPE_WINSIZE       0x08    /* Terminal window size update */
+#define MSG_TYPE_DATA          0x10    /* Terminal data */
+
+struct iucv_tty_msg {
+       u8      version;                /* Message version */
+       u8      type;                   /* Message type */
+#define MSG_MAX_DATALEN                ((u16)(~0))
+       u16     datalen;                /* Payload length */
+       u8      data[];                 /* Payload buffer */
+} __attribute__((packed));
+#define MSG_SIZE(s)            ((s) + offsetof(struct iucv_tty_msg, data))
+
+enum iucv_state_t {
+       IUCV_DISCONN    = 0,
+       IUCV_CONNECTED  = 1,
+       IUCV_SEVERED    = 2,
+};
+
+enum tty_state_t {
+       TTY_CLOSED      = 0,
+       TTY_OPENED      = 1,
+};
+
+struct hvc_iucv_private {
+       struct hvc_struct       *hvc;           /* HVC struct reference */
+       u8                      srv_name[8];    /* IUCV service name (ebcdic) */
+       unsigned char           is_console;     /* Linux console usage flag */
+       enum iucv_state_t       iucv_state;     /* IUCV connection status */
+       enum tty_state_t        tty_state;      /* TTY status */
+       struct iucv_path        *path;          /* IUCV path pointer */
+       spinlock_t              lock;           /* hvc_iucv_private lock */
+#define SNDBUF_SIZE            (PAGE_SIZE)     /* must be < MSG_MAX_DATALEN */
+       void                    *sndbuf;        /* send buffer            */
+       size_t                  sndbuf_len;     /* length of send buffer  */
+#define QUEUE_SNDBUF_DELAY     (HZ / 25)
+       struct delayed_work     sndbuf_work;    /* work: send iucv msg(s) */
+       wait_queue_head_t       sndbuf_waitq;   /* wait for send completion */
+       struct list_head        tty_outqueue;   /* outgoing IUCV messages */
+       struct list_head        tty_inqueue;    /* incoming IUCV messages */
+       struct device           *dev;           /* device structure */
+};
+
+struct iucv_tty_buffer {
+       struct list_head        list;   /* list pointer */
+       struct iucv_message     msg;    /* store an IUCV message */
+       size_t                  offset; /* data buffer offset */
+       struct iucv_tty_msg     *mbuf;  /* buffer to store input/output data */
+};
+
+/* IUCV callback handler */
+static int hvc_iucv_path_pending(struct iucv_path *, u8[8], u8[16]);
+static void hvc_iucv_path_severed(struct iucv_path *, u8[16]);
+static void hvc_iucv_msg_pending(struct iucv_path *, struct iucv_message *);
+static void hvc_iucv_msg_complete(struct iucv_path *, struct iucv_message *);
+
+
+/* Kernel module parameter: use one terminal device as default */
+static unsigned long hvc_iucv_devices = 1;
+
+/* Array of allocated hvc iucv tty lines... */
+static struct hvc_iucv_private *hvc_iucv_table[MAX_HVC_IUCV_LINES];
+#define IUCV_HVC_CON_IDX       (0)
+/* List of z/VM user ID filter entries (struct iucv_vmid_filter) */
+#define MAX_VMID_FILTER                (500)
+static size_t hvc_iucv_filter_size;
+static void *hvc_iucv_filter;
+static const char *hvc_iucv_filter_string;
+static DEFINE_RWLOCK(hvc_iucv_filter_lock);
+
+/* Kmem cache and mempool for iucv_tty_buffer elements */
+static struct kmem_cache *hvc_iucv_buffer_cache;
+static mempool_t *hvc_iucv_mempool;
+
+/* IUCV handler callback functions */
+static struct iucv_handler hvc_iucv_handler = {
+       .path_pending  = hvc_iucv_path_pending,
+       .path_severed  = hvc_iucv_path_severed,
+       .message_complete = hvc_iucv_msg_complete,
+       .message_pending  = hvc_iucv_msg_pending,
+};
+
+
+/**
+ * hvc_iucv_get_private() - Return a struct hvc_iucv_private instance.
+ * @num:       The HVC virtual terminal number (vtermno)
+ *
+ * This function returns the struct hvc_iucv_private instance that corresponds
+ * to the HVC virtual terminal number specified as parameter @num.
+ */
+struct hvc_iucv_private *hvc_iucv_get_private(uint32_t num)
+{
+       if ((num < HVC_IUCV_MAGIC) || (num - HVC_IUCV_MAGIC > hvc_iucv_devices))
+               return NULL;
+       return hvc_iucv_table[num - HVC_IUCV_MAGIC];
+}
+
+/**
+ * alloc_tty_buffer() - Return a new struct iucv_tty_buffer element.
+ * @size:      Size of the internal buffer used to store data.
+ * @flags:     Memory allocation flags passed to mempool.
+ *
+ * This function allocates a new struct iucv_tty_buffer element and, optionally,
+ * allocates an internal data buffer with the specified size @size.
+ * The internal data buffer is always allocated with GFP_DMA which is
+ * required for receiving and sending data with IUCV.
+ * Note: The total message size arises from the internal buffer size and the
+ *      members of the iucv_tty_msg structure.
+ * The function returns NULL if memory allocation has failed.
+ */
+static struct iucv_tty_buffer *alloc_tty_buffer(size_t size, gfp_t flags)
+{
+       struct iucv_tty_buffer *bufp;
+
+       bufp = mempool_alloc(hvc_iucv_mempool, flags);
+       if (!bufp)
+               return NULL;
+       memset(bufp, 0, sizeof(*bufp));
+
+       if (size > 0) {
+               bufp->msg.length = MSG_SIZE(size);
+               bufp->mbuf = kmalloc(bufp->msg.length, flags | GFP_DMA);
+               if (!bufp->mbuf) {
+                       mempool_free(bufp, hvc_iucv_mempool);
+                       return NULL;
+               }
+               bufp->mbuf->version = MSG_VERSION;
+               bufp->mbuf->type    = MSG_TYPE_DATA;
+               bufp->mbuf->datalen = (u16) size;
+       }
+       return bufp;
+}
+
+/**
+ * destroy_tty_buffer() - destroy struct iucv_tty_buffer element.
+ * @bufp:      Pointer to a struct iucv_tty_buffer element, SHALL NOT be NULL.
+ */
+static void destroy_tty_buffer(struct iucv_tty_buffer *bufp)
+{
+       kfree(bufp->mbuf);
+       mempool_free(bufp, hvc_iucv_mempool);
+}
+
+/**
+ * destroy_tty_buffer_list() - call destroy_tty_buffer() for each list element.
+ * @list:      List containing struct iucv_tty_buffer elements.
+ */
+static void destroy_tty_buffer_list(struct list_head *list)
+{
+       struct iucv_tty_buffer *ent, *next;
+
+       list_for_each_entry_safe(ent, next, list, list) {
+               list_del(&ent->list);
+               destroy_tty_buffer(ent);
+       }
+}
+
+/**
+ * hvc_iucv_write() - Receive IUCV message & write data to HVC buffer.
+ * @priv:              Pointer to struct hvc_iucv_private
+ * @buf:               HVC buffer for writing received terminal data.
+ * @count:             HVC buffer size.
+ * @has_more_data:     Pointer to an int variable.
+ *
+ * The function picks up pending messages from the input queue and receives
+ * the message data that is then written to the specified buffer @buf.
+ * If the buffer size @count is less than the data message size, the
+ * message is kept on the input queue and @has_more_data is set to 1.
+ * If all message data has been written, the message is removed from
+ * the input queue.
+ *
+ * The function returns the number of bytes written to the terminal, zero if
+ * there are no pending data messages available or if there is no established
+ * IUCV path.
+ * If the IUCV path has been severed, then -EPIPE is returned to cause a
+ * hang up (that is issued by the HVC layer).
+ */
+static int hvc_iucv_write(struct hvc_iucv_private *priv,
+                         char *buf, int count, int *has_more_data)
+{
+       struct iucv_tty_buffer *rb;
+       int written;
+       int rc;
+
+       /* immediately return if there is no IUCV connection */
+       if (priv->iucv_state == IUCV_DISCONN)
+               return 0;
+
+       /* if the IUCV path has been severed, return -EPIPE to inform the
+        * HVC layer to hang up the tty device. */
+       if (priv->iucv_state == IUCV_SEVERED)
+               return -EPIPE;
+
+       /* check if there are pending messages */
+       if (list_empty(&priv->tty_inqueue))
+               return 0;
+
+       /* receive an iucv message and flip data to the tty (ldisc) */
+       rb = list_first_entry(&priv->tty_inqueue, struct iucv_tty_buffer, list);
+
+       written = 0;
+       if (!rb->mbuf) { /* message not yet received ... */
+               /* allocate mem to store msg data; if no memory is available
+                * then leave the buffer on the list and re-try later */
+               rb->mbuf = kmalloc(rb->msg.length, GFP_ATOMIC | GFP_DMA);
+               if (!rb->mbuf)
+                       return -ENOMEM;
+
+               rc = __iucv_message_receive(priv->path, &rb->msg, 0,
+                                           rb->mbuf, rb->msg.length, NULL);
+               switch (rc) {
+               case 0: /* Successful       */
+                       break;
+               case 2: /* No message found */
+               case 9: /* Message purged   */
+                       break;
+               default:
+                       written = -EIO;
+               }
+               /* remove buffer if an error has occured or received data
+                * is not correct */
+               if (rc || (rb->mbuf->version != MSG_VERSION) ||
+                         (rb->msg.length    != MSG_SIZE(rb->mbuf->datalen)))
+                       goto out_remove_buffer;
+       }
+
+       switch (rb->mbuf->type) {
+       case MSG_TYPE_DATA:
+               written = min_t(int, rb->mbuf->datalen - rb->offset, count);
+               memcpy(buf, rb->mbuf->data + rb->offset, written);
+               if (written < (rb->mbuf->datalen - rb->offset)) {
+                       rb->offset += written;
+                       *has_more_data = 1;
+                       goto out_written;
+               }
+               break;
+
+       case MSG_TYPE_WINSIZE:
+               if (rb->mbuf->datalen != sizeof(struct winsize))
+                       break;
+               /* The caller must ensure that the hvc is locked, which
+                * is the case when called from hvc_iucv_get_chars() */
+               __hvc_resize(priv->hvc, *((struct winsize *) rb->mbuf->data));
+               break;
+
+       case MSG_TYPE_ERROR:    /* ignored ... */
+       case MSG_TYPE_TERMENV:  /* ignored ... */
+       case MSG_TYPE_TERMIOS:  /* ignored ... */
+               break;
+       }
+
+out_remove_buffer:
+       list_del(&rb->list);
+       destroy_tty_buffer(rb);
+       *has_more_data = !list_empty(&priv->tty_inqueue);
+
+out_written:
+       return written;
+}
+
+/**
+ * hvc_iucv_get_chars() - HVC get_chars operation.
+ * @vtermno:   HVC virtual terminal number.
+ * @buf:       Pointer to a buffer to store data
+ * @count:     Size of buffer available for writing
+ *
+ * The HVC thread calls this method to read characters from the back-end.
+ * If an IUCV communication path has been established, pending IUCV messages
+ * are received and data is copied into buffer @buf up to @count bytes.
+ *
+ * Locking:    The routine gets called under an irqsave() spinlock; and
+ *             the routine locks the struct hvc_iucv_private->lock to call
+ *             helper functions.
+ */
+static int hvc_iucv_get_chars(uint32_t vtermno, char *buf, int count)
+{
+       struct hvc_iucv_private *priv = hvc_iucv_get_private(vtermno);
+       int written;
+       int has_more_data;
+
+       if (count <= 0)
+               return 0;
+
+       if (!priv)
+               return -ENODEV;
+
+       spin_lock(&priv->lock);
+       has_more_data = 0;
+       written = hvc_iucv_write(priv, buf, count, &has_more_data);
+       spin_unlock(&priv->lock);
+
+       /* if there are still messages on the queue... schedule another run */
+       if (has_more_data)
+               hvc_kick();
+
+       return written;
+}
+
+/**
+ * hvc_iucv_queue() - Buffer terminal data for sending.
+ * @priv:      Pointer to struct hvc_iucv_private instance.
+ * @buf:       Buffer containing data to send.
+ * @count:     Size of buffer and amount of data to send.
+ *
+ * The function queues data for sending. To actually send the buffered data,
+ * a work queue function is scheduled (with QUEUE_SNDBUF_DELAY).
+ * The function returns the number of data bytes that has been buffered.
+ *
+ * If the device is not connected, data is ignored and the function returns
+ * @count.
+ * If the buffer is full, the function returns 0.
+ * If an existing IUCV communicaton path has been severed, -EPIPE is returned
+ * (that can be passed to HVC layer to cause a tty hangup).
+ */
+static int hvc_iucv_queue(struct hvc_iucv_private *priv, const char *buf,
+                         int count)
+{
+       size_t len;
+
+       if (priv->iucv_state == IUCV_DISCONN)
+               return count;                   /* ignore data */
+
+       if (priv->iucv_state == IUCV_SEVERED)
+               return -EPIPE;
+
+       len = min_t(size_t, count, SNDBUF_SIZE - priv->sndbuf_len);
+       if (!len)
+               return 0;
+
+       memcpy(priv->sndbuf + priv->sndbuf_len, buf, len);
+       priv->sndbuf_len += len;
+
+       if (priv->iucv_state == IUCV_CONNECTED)
+               schedule_delayed_work(&priv->sndbuf_work, QUEUE_SNDBUF_DELAY);
+
+       return len;
+}
+
+/**
+ * hvc_iucv_send() - Send an IUCV message containing terminal data.
+ * @priv:      Pointer to struct hvc_iucv_private instance.
+ *
+ * If an IUCV communication path has been established, the buffered output data
+ * is sent via an IUCV message and the number of bytes sent is returned.
+ * Returns 0 if there is no established IUCV communication path or
+ * -EPIPE if an existing IUCV communicaton path has been severed.
+ */
+static int hvc_iucv_send(struct hvc_iucv_private *priv)
+{
+       struct iucv_tty_buffer *sb;
+       int rc, len;
+
+       if (priv->iucv_state == IUCV_SEVERED)
+               return -EPIPE;
+
+       if (priv->iucv_state == IUCV_DISCONN)
+               return -EIO;
+
+       if (!priv->sndbuf_len)
+               return 0;
+
+       /* allocate internal buffer to store msg data and also compute total
+        * message length */
+       sb = alloc_tty_buffer(priv->sndbuf_len, GFP_ATOMIC);
+       if (!sb)
+               return -ENOMEM;
+
+       memcpy(sb->mbuf->data, priv->sndbuf, priv->sndbuf_len);
+       sb->mbuf->datalen = (u16) priv->sndbuf_len;
+       sb->msg.length = MSG_SIZE(sb->mbuf->datalen);
+
+       list_add_tail(&sb->list, &priv->tty_outqueue);
+
+       rc = __iucv_message_send(priv->path, &sb->msg, 0, 0,
+                                (void *) sb->mbuf, sb->msg.length);
+       if (rc) {
+               /* drop the message here; however we might want to handle
+                * 0x03 (msg limit reached) by trying again... */
+               list_del(&sb->list);
+               destroy_tty_buffer(sb);
+       }
+       len = priv->sndbuf_len;
+       priv->sndbuf_len = 0;
+
+       return len;
+}
+
+/**
+ * hvc_iucv_sndbuf_work() - Send buffered data over IUCV
+ * @work:      Work structure.
+ *
+ * This work queue function sends buffered output data over IUCV and,
+ * if not all buffered data could be sent, reschedules itself.
+ */
+static void hvc_iucv_sndbuf_work(struct work_struct *work)
+{
+       struct hvc_iucv_private *priv;
+
+       priv = container_of(work, struct hvc_iucv_private, sndbuf_work.work);
+       if (!priv)
+               return;
+
+       spin_lock_bh(&priv->lock);
+       hvc_iucv_send(priv);
+       spin_unlock_bh(&priv->lock);
+}
+
+/**
+ * hvc_iucv_put_chars() - HVC put_chars operation.
+ * @vtermno:   HVC virtual terminal number.
+ * @buf:       Pointer to an buffer to read data from
+ * @count:     Size of buffer available for reading
+ *
+ * The HVC thread calls this method to write characters to the back-end.
+ * The function calls hvc_iucv_queue() to queue terminal data for sending.
+ *
+ * Locking:    The method gets called under an irqsave() spinlock; and
+ *             locks struct hvc_iucv_private->lock.
+ */
+static int hvc_iucv_put_chars(uint32_t vtermno, const char *buf, int count)
+{
+       struct hvc_iucv_private *priv = hvc_iucv_get_private(vtermno);
+       int queued;
+
+       if (count <= 0)
+               return 0;
+
+       if (!priv)
+               return -ENODEV;
+
+       spin_lock(&priv->lock);
+       queued = hvc_iucv_queue(priv, buf, count);
+       spin_unlock(&priv->lock);
+
+       return queued;
+}
+
+/**
+ * hvc_iucv_notifier_add() - HVC notifier for opening a TTY for the first time.
+ * @hp:        Pointer to the HVC device (struct hvc_struct)
+ * @id:        Additional data (originally passed to hvc_alloc): the index of an struct
+ *     hvc_iucv_private instance.
+ *
+ * The function sets the tty state to TTY_OPENED for the struct hvc_iucv_private
+ * instance that is derived from @id. Always returns 0.
+ *
+ * Locking:    struct hvc_iucv_private->lock, spin_lock_bh
+ */
+static int hvc_iucv_notifier_add(struct hvc_struct *hp, int id)
+{
+       struct hvc_iucv_private *priv;
+
+       priv = hvc_iucv_get_private(id);
+       if (!priv)
+               return 0;
+
+       spin_lock_bh(&priv->lock);
+       priv->tty_state = TTY_OPENED;
+       spin_unlock_bh(&priv->lock);
+
+       return 0;
+}
+
+/**
+ * hvc_iucv_cleanup() - Clean up and reset a z/VM IUCV HVC instance.
+ * @priv:      Pointer to the struct hvc_iucv_private instance.
+ */
+static void hvc_iucv_cleanup(struct hvc_iucv_private *priv)
+{
+       destroy_tty_buffer_list(&priv->tty_outqueue);
+       destroy_tty_buffer_list(&priv->tty_inqueue);
+
+       priv->tty_state = TTY_CLOSED;
+       priv->iucv_state = IUCV_DISCONN;
+
+       priv->sndbuf_len = 0;
+}
+
+/**
+ * tty_outqueue_empty() - Test if the tty outq is empty
+ * @priv:      Pointer to struct hvc_iucv_private instance.
+ */
+static inline int tty_outqueue_empty(struct hvc_iucv_private *priv)
+{
+       int rc;
+
+       spin_lock_bh(&priv->lock);
+       rc = list_empty(&priv->tty_outqueue);
+       spin_unlock_bh(&priv->lock);
+
+       return rc;
+}
+
+/**
+ * flush_sndbuf_sync() - Flush send buffer and wait for completion
+ * @priv:      Pointer to struct hvc_iucv_private instance.
+ *
+ * The routine cancels a pending sndbuf work, calls hvc_iucv_send()
+ * to flush any buffered terminal output data and waits for completion.
+ */
+static void flush_sndbuf_sync(struct hvc_iucv_private *priv)
+{
+       int sync_wait;
+
+       cancel_delayed_work_sync(&priv->sndbuf_work);
+
+       spin_lock_bh(&priv->lock);
+       hvc_iucv_send(priv);            /* force sending buffered data */
+       sync_wait = !list_empty(&priv->tty_outqueue); /* anything queued ? */
+       spin_unlock_bh(&priv->lock);
+
+       if (sync_wait)
+               wait_event_timeout(priv->sndbuf_waitq,
+                                  tty_outqueue_empty(priv), HZ/10);
+}
+
+/**
+ * hvc_iucv_hangup() - Sever IUCV path and schedule hvc tty hang up
+ * @priv:      Pointer to hvc_iucv_private structure
+ *
+ * This routine severs an existing IUCV communication path and hangs
+ * up the underlying HVC terminal device.
+ * The hang-up occurs only if an IUCV communication path is established;
+ * otherwise there is no need to hang up the terminal device.
+ *
+ * The IUCV HVC hang-up is separated into two steps:
+ * 1. After the IUCV path has been severed, the iucv_state is set to
+ *    IUCV_SEVERED.
+ * 2. Later, when the HVC thread calls hvc_iucv_get_chars(), the
+ *    IUCV_SEVERED state causes the tty hang-up in the HVC layer.
+ *
+ * If the tty has not yet been opened, clean up the hvc_iucv_private
+ * structure to allow re-connects.
+ * If the tty has been opened, let get_chars() return -EPIPE to signal
+ * the HVC layer to hang up the tty and, if so, wake up the HVC thread
+ * to call get_chars()...
+ *
+ * Special notes on hanging up a HVC terminal instantiated as console:
+ * Hang-up:    1. do_tty_hangup() replaces file ops (= hung_up_tty_fops)
+ *             2. do_tty_hangup() calls tty->ops->close() for console_filp
+ *                     => no hangup notifier is called by HVC (default)
+ *             2. hvc_close() returns because of tty_hung_up_p(filp)
+ *                     => no delete notifier is called!
+ * Finally, the back-end is not being notified, thus, the tty session is
+ * kept active (TTY_OPEN) to be ready for re-connects.
+ *
+ * Locking:    spin_lock(&priv->lock) w/o disabling bh
+ */
+static void hvc_iucv_hangup(struct hvc_iucv_private *priv)
+{
+       struct iucv_path *path;
+
+       path = NULL;
+       spin_lock(&priv->lock);
+       if (priv->iucv_state == IUCV_CONNECTED) {
+               path = priv->path;
+               priv->path = NULL;
+               priv->iucv_state = IUCV_SEVERED;
+               if (priv->tty_state == TTY_CLOSED)
+                       hvc_iucv_cleanup(priv);
+               else
+                       /* console is special (see above) */
+                       if (priv->is_console) {
+                               hvc_iucv_cleanup(priv);
+                               priv->tty_state = TTY_OPENED;
+                       } else
+                               hvc_kick();
+       }
+       spin_unlock(&priv->lock);
+
+       /* finally sever path (outside of priv->lock due to lock ordering) */
+       if (path) {
+               iucv_path_sever(path, NULL);
+               iucv_path_free(path);
+       }
+}
+
+/**
+ * hvc_iucv_notifier_hangup() - HVC notifier for TTY hangups.
+ * @hp:                Pointer to the HVC device (struct hvc_struct)
+ * @id:                Additional data (originally passed to hvc_alloc):
+ *             the index of an struct hvc_iucv_private instance.
+ *
+ * This routine notifies the HVC back-end that a tty hangup (carrier loss,
+ * virtual or otherwise) has occured.
+ * The z/VM IUCV HVC device driver ignores virtual hangups (vhangup())
+ * to keep an existing IUCV communication path established.
+ * (Background: vhangup() is called from user space (by getty or login) to
+ *             disable writing to the tty by other applications).
+ * If the tty has been opened and an established IUCV path has been severed
+ * (we caused the tty hangup), the function calls hvc_iucv_cleanup().
+ *
+ * Locking:    struct hvc_iucv_private->lock
+ */
+static void hvc_iucv_notifier_hangup(struct hvc_struct *hp, int id)
+{
+       struct hvc_iucv_private *priv;
+
+       priv = hvc_iucv_get_private(id);
+       if (!priv)
+               return;
+
+       flush_sndbuf_sync(priv);
+
+       spin_lock_bh(&priv->lock);
+       /* NOTE: If the hangup was scheduled by ourself (from the iucv
+        *       path_servered callback [IUCV_SEVERED]), we have to clean up
+        *       our structure and to set state to TTY_CLOSED.
+        *       If the tty was hung up otherwise (e.g. vhangup()), then we
+        *       ignore this hangup and keep an established IUCV path open...
+        *       (...the reason is that we are not able to connect back to the
+        *       client if we disconnect on hang up) */
+       priv->tty_state = TTY_CLOSED;
+
+       if (priv->iucv_state == IUCV_SEVERED)
+               hvc_iucv_cleanup(priv);
+       spin_unlock_bh(&priv->lock);
+}
+
+/**
+ * hvc_iucv_notifier_del() - HVC notifier for closing a TTY for the last time.
+ * @hp:                Pointer to the HVC device (struct hvc_struct)
+ * @id:                Additional data (originally passed to hvc_alloc):
+ *             the index of an struct hvc_iucv_private instance.
+ *
+ * This routine notifies the HVC back-end that the last tty device fd has been
+ * closed.  The function calls hvc_iucv_cleanup() to clean up the struct
+ * hvc_iucv_private instance.
+ *
+ * Locking:    struct hvc_iucv_private->lock
+ */
+static void hvc_iucv_notifier_del(struct hvc_struct *hp, int id)
+{
+       struct hvc_iucv_private *priv;
+       struct iucv_path        *path;
+
+       priv = hvc_iucv_get_private(id);
+       if (!priv)
+               return;
+
+       flush_sndbuf_sync(priv);
+
+       spin_lock_bh(&priv->lock);
+       path = priv->path;              /* save reference to IUCV path */
+       priv->path = NULL;
+       hvc_iucv_cleanup(priv);
+       spin_unlock_bh(&priv->lock);
+
+       /* sever IUCV path outside of priv->lock due to lock ordering of:
+        * priv->lock <--> iucv_table_lock */
+       if (path) {
+               iucv_path_sever(path, NULL);
+               iucv_path_free(path);
+       }
+}
+
+/**
+ * hvc_iucv_filter_connreq() - Filter connection request based on z/VM user ID
+ * @ipvmid:    Originating z/VM user ID (right padded with blanks)
+ *
+ * Returns 0 if the z/VM user ID @ipvmid is allowed to connection, otherwise
+ * non-zero.
+ */
+static int hvc_iucv_filter_connreq(u8 ipvmid[8])
+{
+       size_t i;
+
+       /* Note: default policy is ACCEPT if no filter is set */
+       if (!hvc_iucv_filter_size)
+               return 0;
+
+       for (i = 0; i < hvc_iucv_filter_size; i++)
+               if (0 == memcmp(ipvmid, hvc_iucv_filter + (8 * i), 8))
+                       return 0;
+       return 1;
+}
+
+/**
+ * hvc_iucv_path_pending() - IUCV handler to process a connection request.
+ * @path:      Pending path (struct iucv_path)
+ * @ipvmid:    z/VM system identifier of originator
+ * @ipuser:    User specified data for this path
+ *             (AF_IUCV: port/service name and originator port)
+ *
+ * The function uses the @ipuser data to determine if the pending path belongs
+ * to a terminal managed by this device driver.
+ * If the path belongs to this driver, ensure that the terminal is not accessed
+ * multiple times (only one connection to a terminal is allowed).
+ * If the terminal is not yet connected, the pending path is accepted and is
+ * associated to the appropriate struct hvc_iucv_private instance.
+ *
+ * Returns 0 if @path belongs to a terminal managed by the this device driver;
+ * otherwise returns -ENODEV in order to dispatch this path to other handlers.
+ *
+ * Locking:    struct hvc_iucv_private->lock
+ */
+static int hvc_iucv_path_pending(struct iucv_path *path,
+                                 u8 ipvmid[8], u8 ipuser[16])
+{
+       struct hvc_iucv_private *priv;
+       u8 nuser_data[16];
+       u8 vm_user_id[9];
+       int i, rc;
+
+       priv = NULL;
+       for (i = 0; i < hvc_iucv_devices; i++)
+               if (hvc_iucv_table[i] &&
+                   (0 == memcmp(hvc_iucv_table[i]->srv_name, ipuser, 8))) {
+                       priv = hvc_iucv_table[i];
+                       break;
+               }
+       if (!priv)
+               return -ENODEV;
+
+       /* Enforce that ipvmid is allowed to connect to us */
+       read_lock(&hvc_iucv_filter_lock);
+       rc = hvc_iucv_filter_connreq(ipvmid);
+       read_unlock(&hvc_iucv_filter_lock);
+       if (rc) {
+               iucv_path_sever(path, ipuser);
+               iucv_path_free(path);
+               memcpy(vm_user_id, ipvmid, 8);
+               vm_user_id[8] = 0;
+               pr_info("A connection request from z/VM user ID %s "
+                       "was refused\n", vm_user_id);
+               return 0;
+       }
+
+       spin_lock(&priv->lock);
+
+       /* If the terminal is already connected or being severed, then sever
+        * this path to enforce that there is only ONE established communication
+        * path per terminal. */
+       if (priv->iucv_state != IUCV_DISCONN) {
+               iucv_path_sever(path, ipuser);
+               iucv_path_free(path);
+               goto out_path_handled;
+       }
+
+       /* accept path */
+       memcpy(nuser_data, ipuser + 8, 8);  /* remote service (for af_iucv) */
+       memcpy(nuser_data + 8, ipuser, 8);  /* local service  (for af_iucv) */
+       path->msglim = 0xffff;              /* IUCV MSGLIMIT */
+       path->flags &= ~IUCV_IPRMDATA;      /* TODO: use IUCV_IPRMDATA */
+       rc = iucv_path_accept(path, &hvc_iucv_handler, nuser_data, priv);
+       if (rc) {
+               iucv_path_sever(path, ipuser);
+               iucv_path_free(path);
+               goto out_path_handled;
+       }
+       priv->path = path;
+       priv->iucv_state = IUCV_CONNECTED;
+
+       /* flush buffered output data... */
+       schedule_delayed_work(&priv->sndbuf_work, 5);
+
+out_path_handled:
+       spin_unlock(&priv->lock);
+       return 0;
+}
+
+/**
+ * hvc_iucv_path_severed() - IUCV handler to process a path sever.
+ * @path:      Pending path (struct iucv_path)
+ * @ipuser:    User specified data for this path
+ *             (AF_IUCV: port/service name and originator port)
+ *
+ * This function calls the hvc_iucv_hangup() function for the
+ * respective IUCV HVC terminal.
+ *
+ * Locking:    struct hvc_iucv_private->lock
+ */
+static void hvc_iucv_path_severed(struct iucv_path *path, u8 ipuser[16])
+{
+       struct hvc_iucv_private *priv = path->private;
+
+       hvc_iucv_hangup(priv);
+}
+
+/**
+ * hvc_iucv_msg_pending() - IUCV handler to process an incoming IUCV message.
+ * @path:      Pending path (struct iucv_path)
+ * @msg:       Pointer to the IUCV message
+ *
+ * The function puts an incoming message on the input queue for later
+ * processing (by hvc_iucv_get_chars() / hvc_iucv_write()).
+ * If the tty has not yet been opened, the message is rejected.
+ *
+ * Locking:    struct hvc_iucv_private->lock
+ */
+static void hvc_iucv_msg_pending(struct iucv_path *path,
+                                struct iucv_message *msg)
+{
+       struct hvc_iucv_private *priv = path->private;
+       struct iucv_tty_buffer *rb;
+
+       /* reject messages that exceed max size of iucv_tty_msg->datalen */
+       if (msg->length > MSG_SIZE(MSG_MAX_DATALEN)) {
+               iucv_message_reject(path, msg);
+               return;
+       }
+
+       spin_lock(&priv->lock);
+
+       /* reject messages if tty has not yet been opened */
+       if (priv->tty_state == TTY_CLOSED) {
+               iucv_message_reject(path, msg);
+               goto unlock_return;
+       }
+
+       /* allocate tty buffer to save iucv msg only */
+       rb = alloc_tty_buffer(0, GFP_ATOMIC);
+       if (!rb) {
+               iucv_message_reject(path, msg);
+               goto unlock_return;     /* -ENOMEM */
+       }
+       rb->msg = *msg;
+
+       list_add_tail(&rb->list, &priv->tty_inqueue);
+
+       hvc_kick();     /* wake up hvc thread */
+
+unlock_return:
+       spin_unlock(&priv->lock);
+}
+
+/**
+ * hvc_iucv_msg_complete() - IUCV handler to process message completion
+ * @path:      Pending path (struct iucv_path)
+ * @msg:       Pointer to the IUCV message
+ *
+ * The function is called upon completion of message delivery to remove the
+ * message from the outqueue. Additional delivery information can be found
+ * msg->audit: rejected messages (0x040000 (IPADRJCT)), and
+ *            purged messages   (0x010000 (IPADPGNR)).
+ *
+ * Locking:    struct hvc_iucv_private->lock
+ */
+static void hvc_iucv_msg_complete(struct iucv_path *path,
+                                 struct iucv_message *msg)
+{
+       struct hvc_iucv_private *priv = path->private;
+       struct iucv_tty_buffer  *ent, *next;
+       LIST_HEAD(list_remove);
+
+       spin_lock(&priv->lock);
+       list_for_each_entry_safe(ent, next, &priv->tty_outqueue, list)
+               if (ent->msg.id == msg->id) {
+                       list_move(&ent->list, &list_remove);
+                       break;
+               }
+       wake_up(&priv->sndbuf_waitq);
+       spin_unlock(&priv->lock);
+       destroy_tty_buffer_list(&list_remove);
+}
+
+/**
+ * hvc_iucv_pm_freeze() - Freeze PM callback
+ * @dev:       IUVC HVC terminal device
+ *
+ * Sever an established IUCV communication path and
+ * trigger a hang-up of the underlying HVC terminal.
+ */
+static int hvc_iucv_pm_freeze(struct device *dev)
+{
+       struct hvc_iucv_private *priv = dev_get_drvdata(dev);
+
+       local_bh_disable();
+       hvc_iucv_hangup(priv);
+       local_bh_enable();
+
+       return 0;
+}
+
+/**
+ * hvc_iucv_pm_restore_thaw() - Thaw and restore PM callback
+ * @dev:       IUVC HVC terminal device
+ *
+ * Wake up the HVC thread to trigger hang-up and respective
+ * HVC back-end notifier invocations.
+ */
+static int hvc_iucv_pm_restore_thaw(struct device *dev)
+{
+       hvc_kick();
+       return 0;
+}
+
+
+/* HVC operations */
+static const struct hv_ops hvc_iucv_ops = {
+       .get_chars = hvc_iucv_get_chars,
+       .put_chars = hvc_iucv_put_chars,
+       .notifier_add = hvc_iucv_notifier_add,
+       .notifier_del = hvc_iucv_notifier_del,
+       .notifier_hangup = hvc_iucv_notifier_hangup,
+};
+
+/* Suspend / resume device operations */
+static const struct dev_pm_ops hvc_iucv_pm_ops = {
+       .freeze   = hvc_iucv_pm_freeze,
+       .thaw     = hvc_iucv_pm_restore_thaw,
+       .restore  = hvc_iucv_pm_restore_thaw,
+};
+
+/* IUCV HVC device driver */
+static struct device_driver hvc_iucv_driver = {
+       .name = KMSG_COMPONENT,
+       .bus  = &iucv_bus,
+       .pm   = &hvc_iucv_pm_ops,
+};
+
+/**
+ * hvc_iucv_alloc() - Allocates a new struct hvc_iucv_private instance
+ * @id:                        hvc_iucv_table index
+ * @is_console:                Flag if the instance is used as Linux console
+ *
+ * This function allocates a new hvc_iucv_private structure and stores
+ * the instance in hvc_iucv_table at index @id.
+ * Returns 0 on success; otherwise non-zero.
+ */
+static int __init hvc_iucv_alloc(int id, unsigned int is_console)
+{
+       struct hvc_iucv_private *priv;
+       char name[9];
+       int rc;
+
+       priv = kzalloc(sizeof(struct hvc_iucv_private), GFP_KERNEL);
+       if (!priv)
+               return -ENOMEM;
+
+       spin_lock_init(&priv->lock);
+       INIT_LIST_HEAD(&priv->tty_outqueue);
+       INIT_LIST_HEAD(&priv->tty_inqueue);
+       INIT_DELAYED_WORK(&priv->sndbuf_work, hvc_iucv_sndbuf_work);
+       init_waitqueue_head(&priv->sndbuf_waitq);
+
+       priv->sndbuf = (void *) get_zeroed_page(GFP_KERNEL);
+       if (!priv->sndbuf) {
+               kfree(priv);
+               return -ENOMEM;
+       }
+
+       /* set console flag */
+       priv->is_console = is_console;
+
+       /* allocate hvc device */
+       priv->hvc = hvc_alloc(HVC_IUCV_MAGIC + id, /*             PAGE_SIZE */
+                             HVC_IUCV_MAGIC + id, &hvc_iucv_ops, 256);
+       if (IS_ERR(priv->hvc)) {
+               rc = PTR_ERR(priv->hvc);
+               goto out_error_hvc;
+       }
+
+       /* notify HVC thread instead of using polling */
+       priv->hvc->irq_requested = 1;
+
+       /* setup iucv related information */
+       snprintf(name, 9, "lnxhvc%-2d", id);
+       memcpy(priv->srv_name, name, 8);
+       ASCEBC(priv->srv_name, 8);
+
+       /* create and setup device */
+       priv->dev = kzalloc(sizeof(*priv->dev), GFP_KERNEL);
+       if (!priv->dev) {
+               rc = -ENOMEM;
+               goto out_error_dev;
+       }
+       dev_set_name(priv->dev, "hvc_iucv%d", id);
+       dev_set_drvdata(priv->dev, priv);
+       priv->dev->bus = &iucv_bus;
+       priv->dev->parent = iucv_root;
+       priv->dev->driver = &hvc_iucv_driver;
+       priv->dev->release = (void (*)(struct device *)) kfree;
+       rc = device_register(priv->dev);
+       if (rc) {
+               put_device(priv->dev);
+               goto out_error_dev;
+       }
+
+       hvc_iucv_table[id] = priv;
+       return 0;
+
+out_error_dev:
+       hvc_remove(priv->hvc);
+out_error_hvc:
+       free_page((unsigned long) priv->sndbuf);
+       kfree(priv);
+
+       return rc;
+}
+
+/**
+ * hvc_iucv_destroy() - Destroy and free hvc_iucv_private instances
+ */
+static void __init hvc_iucv_destroy(struct hvc_iucv_private *priv)
+{
+       hvc_remove(priv->hvc);
+       device_unregister(priv->dev);
+       free_page((unsigned long) priv->sndbuf);
+       kfree(priv);
+}
+
+/**
+ * hvc_iucv_parse_filter() - Parse filter for a single z/VM user ID
+ * @filter:    String containing a comma-separated list of z/VM user IDs
+ */
+static const char *hvc_iucv_parse_filter(const char *filter, char *dest)
+{
+       const char *nextdelim, *residual;
+       size_t len;
+
+       nextdelim = strchr(filter, ',');
+       if (nextdelim) {
+               len = nextdelim - filter;
+               residual = nextdelim + 1;
+       } else {
+               len = strlen(filter);
+               residual = filter + len;
+       }
+
+       if (len == 0)
+               return ERR_PTR(-EINVAL);
+
+       /* check for '\n' (if called from sysfs) */
+       if (filter[len - 1] == '\n')
+               len--;
+
+       if (len > 8)
+               return ERR_PTR(-EINVAL);
+
+       /* pad with blanks and save upper case version of user ID */
+       memset(dest, ' ', 8);
+       while (len--)
+               dest[len] = toupper(filter[len]);
+       return residual;
+}
+
+/**
+ * hvc_iucv_setup_filter() - Set up z/VM user ID filter
+ * @filter:    String consisting of a comma-separated list of z/VM user IDs
+ *
+ * The function parses the @filter string and creates an array containing
+ * the list of z/VM user ID filter entries.
+ * Return code 0 means success, -EINVAL if the filter is syntactically
+ * incorrect, -ENOMEM if there was not enough memory to allocate the
+ * filter list array, or -ENOSPC if too many z/VM user IDs have been specified.
+ */
+static int hvc_iucv_setup_filter(const char *val)
+{
+       const char *residual;
+       int err;
+       size_t size, count;
+       void *array, *old_filter;
+
+       count = strlen(val);
+       if (count == 0 || (count == 1 && val[0] == '\n')) {
+               size  = 0;
+               array = NULL;
+               goto out_replace_filter;        /* clear filter */
+       }
+
+       /* count user IDs in order to allocate sufficient memory */
+       size = 1;
+       residual = val;
+       while ((residual = strchr(residual, ',')) != NULL) {
+               residual++;
+               size++;
+       }
+
+       /* check if the specified list exceeds the filter limit */
+       if (size > MAX_VMID_FILTER)
+               return -ENOSPC;
+
+       array = kzalloc(size * 8, GFP_KERNEL);
+       if (!array)
+               return -ENOMEM;
+
+       count = size;
+       residual = val;
+       while (*residual && count) {
+               residual = hvc_iucv_parse_filter(residual,
+                                                array + ((size - count) * 8));
+               if (IS_ERR(residual)) {
+                       err = PTR_ERR(residual);
+                       kfree(array);
+                       goto out_err;
+               }
+               count--;
+       }
+
+out_replace_filter:
+       write_lock_bh(&hvc_iucv_filter_lock);
+       old_filter = hvc_iucv_filter;
+       hvc_iucv_filter_size = size;
+       hvc_iucv_filter = array;
+       write_unlock_bh(&hvc_iucv_filter_lock);
+       kfree(old_filter);
+
+       err = 0;
+out_err:
+       return err;
+}
+
+/**
+ * param_set_vmidfilter() - Set z/VM user ID filter parameter
+ * @val:       String consisting of a comma-separated list of z/VM user IDs
+ * @kp:                Kernel parameter pointing to hvc_iucv_filter array
+ *
+ * The function sets up the z/VM user ID filter specified as comma-separated
+ * list of user IDs in @val.
+ * Note: If it is called early in the boot process, @val is stored and
+ *      parsed later in hvc_iucv_init().
+ */
+static int param_set_vmidfilter(const char *val, const struct kernel_param *kp)
+{
+       int rc;
+
+       if (!MACHINE_IS_VM || !hvc_iucv_devices)
+               return -ENODEV;
+
+       if (!val)
+               return -EINVAL;
+
+       rc = 0;
+       if (slab_is_available())
+               rc = hvc_iucv_setup_filter(val);
+       else
+               hvc_iucv_filter_string = val;   /* defer... */
+       return rc;
+}
+
+/**
+ * param_get_vmidfilter() - Get z/VM user ID filter
+ * @buffer:    Buffer to store z/VM user ID filter,
+ *             (buffer size assumption PAGE_SIZE)
+ * @kp:                Kernel parameter pointing to the hvc_iucv_filter array
+ *
+ * The function stores the filter as a comma-separated list of z/VM user IDs
+ * in @buffer. Typically, sysfs routines call this function for attr show.
+ */
+static int param_get_vmidfilter(char *buffer, const struct kernel_param *kp)
+{
+       int rc;
+       size_t index, len;
+       void *start, *end;
+
+       if (!MACHINE_IS_VM || !hvc_iucv_devices)
+               return -ENODEV;
+
+       rc = 0;
+       read_lock_bh(&hvc_iucv_filter_lock);
+       for (index = 0; index < hvc_iucv_filter_size; index++) {
+               start = hvc_iucv_filter + (8 * index);
+               end   = memchr(start, ' ', 8);
+               len   = (end) ? end - start : 8;
+               memcpy(buffer + rc, start, len);
+               rc += len;
+               buffer[rc++] = ',';
+       }
+       read_unlock_bh(&hvc_iucv_filter_lock);
+       if (rc)
+               buffer[--rc] = '\0';    /* replace last comma and update rc */
+       return rc;
+}
+
+#define param_check_vmidfilter(name, p) __param_check(name, p, void)
+
+static struct kernel_param_ops param_ops_vmidfilter = {
+       .set = param_set_vmidfilter,
+       .get = param_get_vmidfilter,
+};
+
+/**
+ * hvc_iucv_init() - z/VM IUCV HVC device driver initialization
+ */
+static int __init hvc_iucv_init(void)
+{
+       int rc;
+       unsigned int i;
+
+       if (!hvc_iucv_devices)
+               return -ENODEV;
+
+       if (!MACHINE_IS_VM) {
+               pr_notice("The z/VM IUCV HVC device driver cannot "
+                          "be used without z/VM\n");
+               rc = -ENODEV;
+               goto out_error;
+       }
+
+       if (hvc_iucv_devices > MAX_HVC_IUCV_LINES) {
+               pr_err("%lu is not a valid value for the hvc_iucv= "
+                       "kernel parameter\n", hvc_iucv_devices);
+               rc = -EINVAL;
+               goto out_error;
+       }
+
+       /* register IUCV HVC device driver */
+       rc = driver_register(&hvc_iucv_driver);
+       if (rc)
+               goto out_error;
+
+       /* parse hvc_iucv_allow string and create z/VM user ID filter list */
+       if (hvc_iucv_filter_string) {
+               rc = hvc_iucv_setup_filter(hvc_iucv_filter_string);
+               switch (rc) {
+               case 0:
+                       break;
+               case -ENOMEM:
+                       pr_err("Allocating memory failed with "
+                               "reason code=%d\n", 3);
+                       goto out_error;
+               case -EINVAL:
+                       pr_err("hvc_iucv_allow= does not specify a valid "
+                               "z/VM user ID list\n");
+                       goto out_error;
+               case -ENOSPC:
+                       pr_err("hvc_iucv_allow= specifies too many "
+                               "z/VM user IDs\n");
+                       goto out_error;
+               default:
+                       goto out_error;
+               }
+       }
+
+       hvc_iucv_buffer_cache = kmem_cache_create(KMSG_COMPONENT,
+                                          sizeof(struct iucv_tty_buffer),
+                                          0, 0, NULL);
+       if (!hvc_iucv_buffer_cache) {
+               pr_err("Allocating memory failed with reason code=%d\n", 1);
+               rc = -ENOMEM;
+               goto out_error;
+       }
+
+       hvc_iucv_mempool = mempool_create_slab_pool(MEMPOOL_MIN_NR,
+                                                   hvc_iucv_buffer_cache);
+       if (!hvc_iucv_mempool) {
+               pr_err("Allocating memory failed with reason code=%d\n", 2);
+               kmem_cache_destroy(hvc_iucv_buffer_cache);
+               rc = -ENOMEM;
+               goto out_error;
+       }
+
+       /* register the first terminal device as console
+        * (must be done before allocating hvc terminal devices) */
+       rc = hvc_instantiate(HVC_IUCV_MAGIC, IUCV_HVC_CON_IDX, &hvc_iucv_ops);
+       if (rc) {
+               pr_err("Registering HVC terminal device as "
+                      "Linux console failed\n");
+               goto out_error_memory;
+       }
+
+       /* allocate hvc_iucv_private structs */
+       for (i = 0; i < hvc_iucv_devices; i++) {
+               rc = hvc_iucv_alloc(i, (i == IUCV_HVC_CON_IDX) ? 1 : 0);
+               if (rc) {
+                       pr_err("Creating a new HVC terminal device "
+                               "failed with error code=%d\n", rc);
+                       goto out_error_hvc;
+               }
+       }
+
+       /* register IUCV callback handler */
+       rc = iucv_register(&hvc_iucv_handler, 0);
+       if (rc) {
+               pr_err("Registering IUCV handlers failed with error code=%d\n",
+                       rc);
+               goto out_error_hvc;
+       }
+
+       return 0;
+
+out_error_hvc:
+       for (i = 0; i < hvc_iucv_devices; i++)
+               if (hvc_iucv_table[i])
+                       hvc_iucv_destroy(hvc_iucv_table[i]);
+out_error_memory:
+       mempool_destroy(hvc_iucv_mempool);
+       kmem_cache_destroy(hvc_iucv_buffer_cache);
+out_error:
+       if (hvc_iucv_filter)
+               kfree(hvc_iucv_filter);
+       hvc_iucv_devices = 0; /* ensure that we do not provide any device */
+       return rc;
+}
+
+/**
+ * hvc_iucv_config() - Parsing of hvc_iucv=  kernel command line parameter
+ * @val:       Parameter value (numeric)
+ */
+static int __init hvc_iucv_config(char *val)
+{
+        return strict_strtoul(val, 10, &hvc_iucv_devices);
+}
+
+
+device_initcall(hvc_iucv_init);
+__setup("hvc_iucv=", hvc_iucv_config);
+core_param(hvc_iucv_allow, hvc_iucv_filter, vmidfilter, 0640);
diff --git a/drivers/tty/hvc/hvc_rtas.c b/drivers/tty/hvc/hvc_rtas.c
new file mode 100644 (file)
index 0000000..61c4a61
--- /dev/null
@@ -0,0 +1,133 @@
+/*
+ * IBM RTAS driver interface to hvc_console.c
+ *
+ * (C) Copyright IBM Corporation 2001-2005
+ * (C) Copyright Red Hat, Inc. 2005
+ *
+ * Author(s): Maximino Augilar <IBM STI Design Center>
+ *         : Ryan S. Arnold <rsa@us.ibm.com>
+ *         : Utz Bacher <utz.bacher@de.ibm.com>
+ *         : David Woodhouse <dwmw2@infradead.org>
+ *
+ *    inspired by drivers/char/hvc_console.c
+ *    written by Anton Blanchard and Paul Mackerras
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ */
+
+#include <linux/console.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/moduleparam.h>
+#include <linux/types.h>
+
+#include <asm/irq.h>
+#include <asm/rtas.h>
+#include "hvc_console.h"
+
+#define hvc_rtas_cookie 0x67781e15
+struct hvc_struct *hvc_rtas_dev;
+
+static int rtascons_put_char_token = RTAS_UNKNOWN_SERVICE;
+static int rtascons_get_char_token = RTAS_UNKNOWN_SERVICE;
+
+static inline int hvc_rtas_write_console(uint32_t vtermno, const char *buf,
+               int count)
+{
+       int i;
+
+       for (i = 0; i < count; i++) {
+               if (rtas_call(rtascons_put_char_token, 1, 1, NULL, buf[i]))
+                       break;
+       }
+
+       return i;
+}
+
+static int hvc_rtas_read_console(uint32_t vtermno, char *buf, int count)
+{
+       int i, c;
+
+       for (i = 0; i < count; i++) {
+               if (rtas_call(rtascons_get_char_token, 0, 2, &c))
+                       break;
+
+               buf[i] = c;
+       }
+
+       return i;
+}
+
+static const struct hv_ops hvc_rtas_get_put_ops = {
+       .get_chars = hvc_rtas_read_console,
+       .put_chars = hvc_rtas_write_console,
+};
+
+static int __init hvc_rtas_init(void)
+{
+       struct hvc_struct *hp;
+
+       if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE)
+               rtascons_put_char_token = rtas_token("put-term-char");
+       if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE)
+               return -EIO;
+
+       if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE)
+               rtascons_get_char_token = rtas_token("get-term-char");
+       if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE)
+               return -EIO;
+
+       BUG_ON(hvc_rtas_dev);
+
+       /* Allocate an hvc_struct for the console device we instantiated
+        * earlier.  Save off hp so that we can return it on exit */
+       hp = hvc_alloc(hvc_rtas_cookie, NO_IRQ, &hvc_rtas_get_put_ops, 16);
+       if (IS_ERR(hp))
+               return PTR_ERR(hp);
+
+       hvc_rtas_dev = hp;
+
+       return 0;
+}
+module_init(hvc_rtas_init);
+
+/* This will tear down the tty portion of the driver */
+static void __exit hvc_rtas_exit(void)
+{
+       /* Really the fun isn't over until the worker thread breaks down and
+        * the tty cleans up */
+       if (hvc_rtas_dev)
+               hvc_remove(hvc_rtas_dev);
+}
+module_exit(hvc_rtas_exit);
+
+/* This will happen prior to module init.  There is no tty at this time? */
+static int __init hvc_rtas_console_init(void)
+{
+       rtascons_put_char_token = rtas_token("put-term-char");
+       if (rtascons_put_char_token == RTAS_UNKNOWN_SERVICE)
+               return -EIO;
+
+       rtascons_get_char_token = rtas_token("get-term-char");
+       if (rtascons_get_char_token == RTAS_UNKNOWN_SERVICE)
+               return -EIO;
+
+       hvc_instantiate(hvc_rtas_cookie, 0, &hvc_rtas_get_put_ops);
+       add_preferred_console("hvc", 0, NULL);
+
+       return 0;
+}
+console_initcall(hvc_rtas_console_init);
diff --git a/drivers/tty/hvc/hvc_tile.c b/drivers/tty/hvc/hvc_tile.c
new file mode 100644 (file)
index 0000000..7a84a05
--- /dev/null
@@ -0,0 +1,68 @@
+/*
+ * Copyright 2010 Tilera Corporation. All Rights Reserved.
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful, but
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ *   NON INFRINGEMENT.  See the GNU General Public License for
+ *   more details.
+ *
+ * Tilera TILE Processor hypervisor console
+ */
+
+#include <linux/console.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/moduleparam.h>
+#include <linux/types.h>
+
+#include <hv/hypervisor.h>
+
+#include "hvc_console.h"
+
+static int hvc_tile_put_chars(uint32_t vt, const char *buf, int count)
+{
+       return hv_console_write((HV_VirtAddr)buf, count);
+}
+
+static int hvc_tile_get_chars(uint32_t vt, char *buf, int count)
+{
+       int i, c;
+
+       for (i = 0; i < count; ++i) {
+               c = hv_console_read_if_ready();
+               if (c < 0)
+                       break;
+               buf[i] = c;
+       }
+
+       return i;
+}
+
+static const struct hv_ops hvc_tile_get_put_ops = {
+       .get_chars = hvc_tile_get_chars,
+       .put_chars = hvc_tile_put_chars,
+};
+
+static int __init hvc_tile_console_init(void)
+{
+       extern void disable_early_printk(void);
+       hvc_instantiate(0, 0, &hvc_tile_get_put_ops);
+       add_preferred_console("hvc", 0, NULL);
+       disable_early_printk();
+       return 0;
+}
+console_initcall(hvc_tile_console_init);
+
+static int __init hvc_tile_init(void)
+{
+       struct hvc_struct *s;
+       s = hvc_alloc(0, 0, &hvc_tile_get_put_ops, 128);
+       return IS_ERR(s) ? PTR_ERR(s) : 0;
+}
+device_initcall(hvc_tile_init);
diff --git a/drivers/tty/hvc/hvc_udbg.c b/drivers/tty/hvc/hvc_udbg.c
new file mode 100644 (file)
index 0000000..b0957e6
--- /dev/null
@@ -0,0 +1,96 @@
+/*
+ * udbg interface to hvc_console.c
+ *
+ * (C) Copyright David Gibson, IBM Corporation 2008.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ */
+
+#include <linux/console.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/moduleparam.h>
+#include <linux/types.h>
+#include <linux/irq.h>
+
+#include <asm/udbg.h>
+
+#include "hvc_console.h"
+
+struct hvc_struct *hvc_udbg_dev;
+
+static int hvc_udbg_put(uint32_t vtermno, const char *buf, int count)
+{
+       int i;
+
+       for (i = 0; i < count; i++)
+               udbg_putc(buf[i]);
+
+       return i;
+}
+
+static int hvc_udbg_get(uint32_t vtermno, char *buf, int count)
+{
+       int i, c;
+
+       if (!udbg_getc_poll)
+               return 0;
+
+       for (i = 0; i < count; i++) {
+               if ((c = udbg_getc_poll()) == -1)
+                       break;
+               buf[i] = c;
+       }
+
+       return i;
+}
+
+static const struct hv_ops hvc_udbg_ops = {
+       .get_chars = hvc_udbg_get,
+       .put_chars = hvc_udbg_put,
+};
+
+static int __init hvc_udbg_init(void)
+{
+       struct hvc_struct *hp;
+
+       BUG_ON(hvc_udbg_dev);
+
+       hp = hvc_alloc(0, NO_IRQ, &hvc_udbg_ops, 16);
+       if (IS_ERR(hp))
+               return PTR_ERR(hp);
+
+       hvc_udbg_dev = hp;
+
+       return 0;
+}
+module_init(hvc_udbg_init);
+
+static void __exit hvc_udbg_exit(void)
+{
+       if (hvc_udbg_dev)
+               hvc_remove(hvc_udbg_dev);
+}
+module_exit(hvc_udbg_exit);
+
+static int __init hvc_udbg_console_init(void)
+{
+       hvc_instantiate(0, 0, &hvc_udbg_ops);
+       add_preferred_console("hvc", 0, NULL);
+
+       return 0;
+}
+console_initcall(hvc_udbg_console_init);
diff --git a/drivers/tty/hvc/hvc_vio.c b/drivers/tty/hvc/hvc_vio.c
new file mode 100644 (file)
index 0000000..5e2f52b
--- /dev/null
@@ -0,0 +1,173 @@
+/*
+ * vio driver interface to hvc_console.c
+ *
+ * This code was moved here to allow the remaing code to be reused as a
+ * generic polling mode with semi-reliable transport driver core to the
+ * console and tty subsystems.
+ *
+ *
+ * Copyright (C) 2001 Anton Blanchard <anton@au.ibm.com>, IBM
+ * Copyright (C) 2001 Paul Mackerras <paulus@au.ibm.com>, IBM
+ * Copyright (C) 2004 Benjamin Herrenschmidt <benh@kernel.crashing.org>, IBM Corp.
+ * Copyright (C) 2004 IBM Corporation
+ *
+ * Additional Author(s):
+ *  Ryan S. Arnold <rsa@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ */
+
+#include <linux/types.h>
+#include <linux/init.h>
+
+#include <asm/hvconsole.h>
+#include <asm/vio.h>
+#include <asm/prom.h>
+#include <asm/firmware.h>
+
+#include "hvc_console.h"
+
+static const char hvc_driver_name[] = "hvc_console";
+
+static struct vio_device_id hvc_driver_table[] __devinitdata = {
+       {"serial", "hvterm1"},
+       { "", "" }
+};
+MODULE_DEVICE_TABLE(vio, hvc_driver_table);
+
+static int filtered_get_chars(uint32_t vtermno, char *buf, int count)
+{
+       unsigned long got;
+       int i;
+
+       /*
+        * Vio firmware will read up to SIZE_VIO_GET_CHARS at its own discretion
+        * so we play safe and avoid the situation where got > count which could
+        * overload the flip buffer.
+        */
+       if (count < SIZE_VIO_GET_CHARS)
+               return -EAGAIN;
+
+       got = hvc_get_chars(vtermno, buf, count);
+
+       /*
+        * Work around a HV bug where it gives us a null
+        * after every \r.  -- paulus
+        */
+       for (i = 1; i < got; ++i) {
+               if (buf[i] == 0 && buf[i-1] == '\r') {
+                       --got;
+                       if (i < got)
+                               memmove(&buf[i], &buf[i+1],
+                                       got - i);
+               }
+       }
+       return got;
+}
+
+static const struct hv_ops hvc_get_put_ops = {
+       .get_chars = filtered_get_chars,
+       .put_chars = hvc_put_chars,
+       .notifier_add = notifier_add_irq,
+       .notifier_del = notifier_del_irq,
+       .notifier_hangup = notifier_hangup_irq,
+};
+
+static int __devinit hvc_vio_probe(struct vio_dev *vdev,
+                               const struct vio_device_id *id)
+{
+       struct hvc_struct *hp;
+
+       /* probed with invalid parameters. */
+       if (!vdev || !id)
+               return -EPERM;
+
+       hp = hvc_alloc(vdev->unit_address, vdev->irq, &hvc_get_put_ops,
+                       MAX_VIO_PUT_CHARS);
+       if (IS_ERR(hp))
+               return PTR_ERR(hp);
+       dev_set_drvdata(&vdev->dev, hp);
+
+       return 0;
+}
+
+static int __devexit hvc_vio_remove(struct vio_dev *vdev)
+{
+       struct hvc_struct *hp = dev_get_drvdata(&vdev->dev);
+
+       return hvc_remove(hp);
+}
+
+static struct vio_driver hvc_vio_driver = {
+       .id_table       = hvc_driver_table,
+       .probe          = hvc_vio_probe,
+       .remove         = __devexit_p(hvc_vio_remove),
+       .driver         = {
+               .name   = hvc_driver_name,
+               .owner  = THIS_MODULE,
+       }
+};
+
+static int __init hvc_vio_init(void)
+{
+       int rc;
+
+       if (firmware_has_feature(FW_FEATURE_ISERIES))
+               return -EIO;
+
+       /* Register as a vio device to receive callbacks */
+       rc = vio_register_driver(&hvc_vio_driver);
+
+       return rc;
+}
+module_init(hvc_vio_init); /* after drivers/char/hvc_console.c */
+
+static void __exit hvc_vio_exit(void)
+{
+       vio_unregister_driver(&hvc_vio_driver);
+}
+module_exit(hvc_vio_exit);
+
+/* the device tree order defines our numbering */
+static int hvc_find_vtys(void)
+{
+       struct device_node *vty;
+       int num_found = 0;
+
+       for (vty = of_find_node_by_name(NULL, "vty"); vty != NULL;
+                       vty = of_find_node_by_name(vty, "vty")) {
+               const uint32_t *vtermno;
+
+               /* We have statically defined space for only a certain number
+                * of console adapters.
+                */
+               if (num_found >= MAX_NR_HVC_CONSOLES) {
+                       of_node_put(vty);
+                       break;
+               }
+
+               vtermno = of_get_property(vty, "reg", NULL);
+               if (!vtermno)
+                       continue;
+
+               if (of_device_is_compatible(vty, "hvterm1")) {
+                       hvc_instantiate(*vtermno, num_found, &hvc_get_put_ops);
+                       ++num_found;
+               }
+       }
+
+       return num_found;
+}
+console_initcall(hvc_find_vtys);
diff --git a/drivers/tty/hvc/hvc_xen.c b/drivers/tty/hvc/hvc_xen.c
new file mode 100644 (file)
index 0000000..3740e32
--- /dev/null
@@ -0,0 +1,271 @@
+/*
+ * xen console driver interface to hvc_console.c
+ *
+ * (c) 2007 Gerd Hoffmann <kraxel@suse.de>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ */
+
+#include <linux/console.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/types.h>
+
+#include <asm/xen/hypervisor.h>
+
+#include <xen/xen.h>
+#include <xen/page.h>
+#include <xen/events.h>
+#include <xen/interface/io/console.h>
+#include <xen/hvc-console.h>
+
+#include "hvc_console.h"
+
+#define HVC_COOKIE   0x58656e /* "Xen" in hex */
+
+static struct hvc_struct *hvc;
+static int xencons_irq;
+
+/* ------------------------------------------------------------------ */
+
+static unsigned long console_pfn = ~0ul;
+
+static inline struct xencons_interface *xencons_interface(void)
+{
+       if (console_pfn == ~0ul)
+               return mfn_to_virt(xen_start_info->console.domU.mfn);
+       else
+               return __va(console_pfn << PAGE_SHIFT);
+}
+
+static inline void notify_daemon(void)
+{
+       /* Use evtchn: this is called early, before irq is set up. */
+       notify_remote_via_evtchn(xen_start_info->console.domU.evtchn);
+}
+
+static int __write_console(const char *data, int len)
+{
+       struct xencons_interface *intf = xencons_interface();
+       XENCONS_RING_IDX cons, prod;
+       int sent = 0;
+
+       cons = intf->out_cons;
+       prod = intf->out_prod;
+       mb();                   /* update queue values before going on */
+       BUG_ON((prod - cons) > sizeof(intf->out));
+
+       while ((sent < len) && ((prod - cons) < sizeof(intf->out)))
+               intf->out[MASK_XENCONS_IDX(prod++, intf->out)] = data[sent++];
+
+       wmb();                  /* write ring before updating pointer */
+       intf->out_prod = prod;
+
+       if (sent)
+               notify_daemon();
+       return sent;
+}
+
+static int domU_write_console(uint32_t vtermno, const char *data, int len)
+{
+       int ret = len;
+
+       /*
+        * Make sure the whole buffer is emitted, polling if
+        * necessary.  We don't ever want to rely on the hvc daemon
+        * because the most interesting console output is when the
+        * kernel is crippled.
+        */
+       while (len) {
+               int sent = __write_console(data, len);
+               
+               data += sent;
+               len -= sent;
+
+               if (unlikely(len))
+                       HYPERVISOR_sched_op(SCHEDOP_yield, NULL);
+       }
+
+       return ret;
+}
+
+static int domU_read_console(uint32_t vtermno, char *buf, int len)
+{
+       struct xencons_interface *intf = xencons_interface();
+       XENCONS_RING_IDX cons, prod;
+       int recv = 0;
+
+       cons = intf->in_cons;
+       prod = intf->in_prod;
+       mb();                   /* get pointers before reading ring */
+       BUG_ON((prod - cons) > sizeof(intf->in));
+
+       while (cons != prod && recv < len)
+               buf[recv++] = intf->in[MASK_XENCONS_IDX(cons++, intf->in)];
+
+       mb();                   /* read ring before consuming */
+       intf->in_cons = cons;
+
+       notify_daemon();
+       return recv;
+}
+
+static struct hv_ops domU_hvc_ops = {
+       .get_chars = domU_read_console,
+       .put_chars = domU_write_console,
+       .notifier_add = notifier_add_irq,
+       .notifier_del = notifier_del_irq,
+       .notifier_hangup = notifier_hangup_irq,
+};
+
+static int dom0_read_console(uint32_t vtermno, char *buf, int len)
+{
+       return HYPERVISOR_console_io(CONSOLEIO_read, len, buf);
+}
+
+/*
+ * Either for a dom0 to write to the system console, or a domU with a
+ * debug version of Xen
+ */
+static int dom0_write_console(uint32_t vtermno, const char *str, int len)
+{
+       int rc = HYPERVISOR_console_io(CONSOLEIO_write, len, (char *)str);
+       if (rc < 0)
+               return 0;
+
+       return len;
+}
+
+static struct hv_ops dom0_hvc_ops = {
+       .get_chars = dom0_read_console,
+       .put_chars = dom0_write_console,
+       .notifier_add = notifier_add_irq,
+       .notifier_del = notifier_del_irq,
+       .notifier_hangup = notifier_hangup_irq,
+};
+
+static int __init xen_hvc_init(void)
+{
+       struct hvc_struct *hp;
+       struct hv_ops *ops;
+
+       if (!xen_pv_domain())
+               return -ENODEV;
+
+       if (xen_initial_domain()) {
+               ops = &dom0_hvc_ops;
+               xencons_irq = bind_virq_to_irq(VIRQ_CONSOLE, 0);
+       } else {
+               if (!xen_start_info->console.domU.evtchn)
+                       return -ENODEV;
+
+               ops = &domU_hvc_ops;
+               xencons_irq = bind_evtchn_to_irq(xen_start_info->console.domU.evtchn);
+       }
+       if (xencons_irq < 0)
+               xencons_irq = 0; /* NO_IRQ */
+
+       hp = hvc_alloc(HVC_COOKIE, xencons_irq, ops, 256);
+       if (IS_ERR(hp))
+               return PTR_ERR(hp);
+
+       hvc = hp;
+
+       console_pfn = mfn_to_pfn(xen_start_info->console.domU.mfn);
+
+       return 0;
+}
+
+void xen_console_resume(void)
+{
+       if (xencons_irq)
+               rebind_evtchn_irq(xen_start_info->console.domU.evtchn, xencons_irq);
+}
+
+static void __exit xen_hvc_fini(void)
+{
+       if (hvc)
+               hvc_remove(hvc);
+}
+
+static int xen_cons_init(void)
+{
+       struct hv_ops *ops;
+
+       if (!xen_pv_domain())
+               return 0;
+
+       if (xen_initial_domain())
+               ops = &dom0_hvc_ops;
+       else
+               ops = &domU_hvc_ops;
+
+       hvc_instantiate(HVC_COOKIE, 0, ops);
+       return 0;
+}
+
+module_init(xen_hvc_init);
+module_exit(xen_hvc_fini);
+console_initcall(xen_cons_init);
+
+#ifdef CONFIG_EARLY_PRINTK
+static void xenboot_write_console(struct console *console, const char *string,
+                                 unsigned len)
+{
+       unsigned int linelen, off = 0;
+       const char *pos;
+
+       dom0_write_console(0, string, len);
+
+       if (xen_initial_domain())
+               return;
+
+       domU_write_console(0, "(early) ", 8);
+       while (off < len && NULL != (pos = strchr(string+off, '\n'))) {
+               linelen = pos-string+off;
+               if (off + linelen > len)
+                       break;
+               domU_write_console(0, string+off, linelen);
+               domU_write_console(0, "\r\n", 2);
+               off += linelen + 1;
+       }
+       if (off < len)
+               domU_write_console(0, string+off, len-off);
+}
+
+struct console xenboot_console = {
+       .name           = "xenboot",
+       .write          = xenboot_write_console,
+       .flags          = CON_PRINTBUFFER | CON_BOOT | CON_ANYTIME,
+};
+#endif /* CONFIG_EARLY_PRINTK */
+
+void xen_raw_console_write(const char *str)
+{
+       dom0_write_console(0, str, strlen(str));
+}
+
+void xen_raw_printk(const char *fmt, ...)
+{
+       static char buf[512];
+       va_list ap;
+
+       va_start(ap, fmt);
+       vsnprintf(buf, sizeof(buf), fmt, ap);
+       va_end(ap);
+
+       xen_raw_console_write(buf);
+}
diff --git a/drivers/tty/hvc/hvcs.c b/drivers/tty/hvc/hvcs.c
new file mode 100644 (file)
index 0000000..bedc6c1
--- /dev/null
@@ -0,0 +1,1604 @@
+/*
+ * IBM eServer Hypervisor Virtual Console Server Device Driver
+ * Copyright (C) 2003, 2004 IBM Corp.
+ *  Ryan S. Arnold (rsa@us.ibm.com)
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with this program; if not, write to the Free Software
+ *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ *
+ * Author(s) :  Ryan S. Arnold <rsa@us.ibm.com>
+ *
+ * This is the device driver for the IBM Hypervisor Virtual Console Server,
+ * "hvcs".  The IBM hvcs provides a tty driver interface to allow Linux
+ * user space applications access to the system consoles of logically
+ * partitioned operating systems, e.g. Linux, running on the same partitioned
+ * Power5 ppc64 system.  Physical hardware consoles per partition are not
+ * practical on this hardware so system consoles are accessed by this driver
+ * using inter-partition firmware interfaces to virtual terminal devices.
+ *
+ * A vty is known to the HMC as a "virtual serial server adapter".  It is a
+ * virtual terminal device that is created by firmware upon partition creation
+ * to act as a partitioned OS's console device.
+ *
+ * Firmware dynamically (via hotplug) exposes vty-servers to a running ppc64
+ * Linux system upon their creation by the HMC or their exposure during boot.
+ * The non-user interactive backend of this driver is implemented as a vio
+ * device driver so that it can receive notification of vty-server lifetimes
+ * after it registers with the vio bus to handle vty-server probe and remove
+ * callbacks.
+ *
+ * Many vty-servers can be configured to connect to one vty, but a vty can
+ * only be actively connected to by a single vty-server, in any manner, at one
+ * time.  If the HMC is currently hosting the console for a target Linux
+ * partition; attempts to open the tty device to the partition's console using
+ * the hvcs on any partition will return -EBUSY with every open attempt until
+ * the HMC frees the connection between its vty-server and the desired
+ * partition's vty device.  Conversely, a vty-server may only be connected to
+ * a single vty at one time even though it may have several configured vty
+ * partner possibilities.
+ *
+ * Firmware does not provide notification of vty partner changes to this
+ * driver.  This means that an HMC Super Admin may add or remove partner vtys
+ * from a vty-server's partner list but the changes will not be signaled to
+ * the vty-server.  Firmware only notifies the driver when a vty-server is
+ * added or removed from the system.  To compensate for this deficiency, this
+ * driver implements a sysfs update attribute which provides a method for
+ * rescanning partner information upon a user's request.
+ *
+ * Each vty-server, prior to being exposed to this driver is reference counted
+ * using the 2.6 Linux kernel kref construct.
+ *
+ * For direction on installation and usage of this driver please reference
+ * Documentation/powerpc/hvcs.txt.
+ */
+
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/kref.h>
+#include <linux/kthread.h>
+#include <linux/list.h>
+#include <linux/major.h>
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/stat.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <asm/hvconsole.h>
+#include <asm/hvcserver.h>
+#include <asm/uaccess.h>
+#include <asm/vio.h>
+
+/*
+ * 1.3.0 -> 1.3.1 In hvcs_open memset(..,0x00,..) instead of memset(..,0x3F,00).
+ * Removed braces around single statements following conditionals.  Removed '=
+ * 0' after static int declarations since these default to zero.  Removed
+ * list_for_each_safe() and replaced with list_for_each_entry() in
+ * hvcs_get_by_index().  The 'safe' version is un-needed now that the driver is
+ * using spinlocks.  Changed spin_lock_irqsave() to spin_lock() when locking
+ * hvcs_structs_lock and hvcs_pi_lock since these are not touched in an int
+ * handler.  Initialized hvcs_structs_lock and hvcs_pi_lock to
+ * SPIN_LOCK_UNLOCKED at declaration time rather than in hvcs_module_init().
+ * Added spin_lock around list_del() in destroy_hvcs_struct() to protect the
+ * list traversals from a deletion.  Removed '= NULL' from pointer declaration
+ * statements since they are initialized NULL by default.  Removed wmb()
+ * instances from hvcs_try_write().  They probably aren't needed with locking in
+ * place.  Added check and cleanup for hvcs_pi_buff = kmalloc() in
+ * hvcs_module_init().  Exposed hvcs_struct.index via a sysfs attribute so that
+ * the coupling between /dev/hvcs* and a vty-server can be automatically
+ * determined.  Moved kobject_put() in hvcs_open outside of the
+ * spin_unlock_irqrestore().
+ *
+ * 1.3.1 -> 1.3.2 Changed method for determining hvcs_struct->index and had it
+ * align with how the tty layer always assigns the lowest index available.  This
+ * change resulted in a list of ints that denotes which indexes are available.
+ * Device additions and removals use the new hvcs_get_index() and
+ * hvcs_return_index() helper functions.  The list is created with
+ * hvsc_alloc_index_list() and it is destroyed with hvcs_free_index_list().
+ * Without these fixes hotplug vty-server adapter support goes crazy with this
+ * driver if the user removes a vty-server adapter.  Moved free_irq() outside of
+ * the hvcs_final_close() function in order to get it out of the spinlock.
+ * Rearranged hvcs_close().  Cleaned up some printks and did some housekeeping
+ * on the changelog.  Removed local CLC_LENGTH and used HVCS_CLC_LENGTH from
+ * arch/powerepc/include/asm/hvcserver.h
+ *
+ * 1.3.2 -> 1.3.3 Replaced yield() in hvcs_close() with tty_wait_until_sent() to
+ * prevent possible lockup with realtime scheduling as similarily pointed out by
+ * akpm in hvc_console.  Changed resulted in the removal of hvcs_final_close()
+ * to reorder cleanup operations and prevent discarding of pending data during
+ * an hvcs_close().  Removed spinlock protection of hvcs_struct data members in
+ * hvcs_write_room() and hvcs_chars_in_buffer() because they aren't needed.
+ */
+
+#define HVCS_DRIVER_VERSION "1.3.3"
+
+MODULE_AUTHOR("Ryan S. Arnold <rsa@us.ibm.com>");
+MODULE_DESCRIPTION("IBM hvcs (Hypervisor Virtual Console Server) Driver");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(HVCS_DRIVER_VERSION);
+
+/*
+ * Wait this long per iteration while trying to push buffered data to the
+ * hypervisor before allowing the tty to complete a close operation.
+ */
+#define HVCS_CLOSE_WAIT (HZ/100) /* 1/10 of a second */
+
+/*
+ * Since the Linux TTY code does not currently (2-04-2004) support dynamic
+ * addition of tty derived devices and we shouldn't allocate thousands of
+ * tty_device pointers when the number of vty-server & vty partner connections
+ * will most often be much lower than this, we'll arbitrarily allocate
+ * HVCS_DEFAULT_SERVER_ADAPTERS tty_structs and cdev's by default when we
+ * register the tty_driver. This can be overridden using an insmod parameter.
+ */
+#define HVCS_DEFAULT_SERVER_ADAPTERS   64
+
+/*
+ * The user can't insmod with more than HVCS_MAX_SERVER_ADAPTERS hvcs device
+ * nodes as a sanity check.  Theoretically there can be over 1 Billion
+ * vty-server & vty partner connections.
+ */
+#define HVCS_MAX_SERVER_ADAPTERS       1024
+
+/*
+ * We let Linux assign us a major number and we start the minors at zero.  There
+ * is no intuitive mapping between minor number and the target vty-server
+ * adapter except that each new vty-server adapter is always assigned to the
+ * smallest minor number available.
+ */
+#define HVCS_MINOR_START       0
+
+/*
+ * The hcall interface involves putting 8 chars into each of two registers.
+ * We load up those 2 registers (in arch/powerpc/platforms/pseries/hvconsole.c)
+ * by casting char[16] to long[2].  It would work without __ALIGNED__, but a 
+ * little (tiny) bit slower because an unaligned load is slower than aligned 
+ * load.
+ */
+#define __ALIGNED__    __attribute__((__aligned__(8)))
+
+/*
+ * How much data can firmware send with each hvc_put_chars()?  Maybe this
+ * should be moved into an architecture specific area.
+ */
+#define HVCS_BUFF_LEN  16
+
+/*
+ * This is the maximum amount of data we'll let the user send us (hvcs_write) at
+ * once in a chunk as a sanity check.
+ */
+#define HVCS_MAX_FROM_USER     4096
+
+/*
+ * Be careful when adding flags to this line discipline.  Don't add anything
+ * that will cause echoing or we'll go into recursive loop echoing chars back
+ * and forth with the console drivers.
+ */
+static struct ktermios hvcs_tty_termios = {
+       .c_iflag = IGNBRK | IGNPAR,
+       .c_oflag = OPOST,
+       .c_cflag = B38400 | CS8 | CREAD | HUPCL,
+       .c_cc = INIT_C_CC,
+       .c_ispeed = 38400,
+       .c_ospeed = 38400
+};
+
+/*
+ * This value is used to take the place of a command line parameter when the
+ * module is inserted.  It starts as -1 and stays as such if the user doesn't
+ * specify a module insmod parameter.  If they DO specify one then it is set to
+ * the value of the integer passed in.
+ */
+static int hvcs_parm_num_devs = -1;
+module_param(hvcs_parm_num_devs, int, 0);
+
+static const char hvcs_driver_name[] = "hvcs";
+static const char hvcs_device_node[] = "hvcs";
+static const char hvcs_driver_string[]
+       = "IBM hvcs (Hypervisor Virtual Console Server) Driver";
+
+/* Status of partner info rescan triggered via sysfs. */
+static int hvcs_rescan_status;
+
+static struct tty_driver *hvcs_tty_driver;
+
+/*
+ * In order to be somewhat sane this driver always associates the hvcs_struct
+ * index element with the numerically equal tty->index.  This means that a
+ * hotplugged vty-server adapter will always map to the lowest index valued
+ * device node.  If vty-servers were hotplug removed from the system and then
+ * new ones added the new vty-server may have the largest slot number of all
+ * the vty-server adapters in the partition but it may have the lowest dev node
+ * index of all the adapters due to the hole left by the hotplug removed
+ * adapter.  There are a set of functions provided to get the lowest index for
+ * a new device as well as return the index to the list.  This list is allocated
+ * with a number of elements equal to the number of device nodes requested when
+ * the module was inserted.
+ */
+static int *hvcs_index_list;
+
+/*
+ * How large is the list?  This is kept for traversal since the list is
+ * dynamically created.
+ */
+static int hvcs_index_count;
+
+/*
+ * Used by the khvcsd to pick up I/O operations when the kernel_thread is
+ * already awake but potentially shifted to TASK_INTERRUPTIBLE state.
+ */
+static int hvcs_kicked;
+
+/*
+ * Use by the kthread construct for task operations like waking the sleeping
+ * thread and stopping the kthread.
+ */
+static struct task_struct *hvcs_task;
+
+/*
+ * We allocate this for the use of all of the hvcs_structs when they fetch
+ * partner info.
+ */
+static unsigned long *hvcs_pi_buff;
+
+/* Only allow one hvcs_struct to use the hvcs_pi_buff at a time. */
+static DEFINE_SPINLOCK(hvcs_pi_lock);
+
+/* One vty-server per hvcs_struct */
+struct hvcs_struct {
+       spinlock_t lock;
+
+       /*
+        * This index identifies this hvcs device as the complement to a
+        * specific tty index.
+        */
+       unsigned int index;
+
+       struct tty_struct *tty;
+       int open_count;
+
+       /*
+        * Used to tell the driver kernel_thread what operations need to take
+        * place upon this hvcs_struct instance.
+        */
+       int todo_mask;
+
+       /*
+        * This buffer is required so that when hvcs_write_room() reports that
+        * it can send HVCS_BUFF_LEN characters that it will buffer the full
+        * HVCS_BUFF_LEN characters if need be.  This is essential for opost
+        * writes since they do not do high level buffering and expect to be
+        * able to send what the driver commits to sending buffering
+        * [e.g. tab to space conversions in n_tty.c opost()].
+        */
+       char buffer[HVCS_BUFF_LEN];
+       int chars_in_buffer;
+
+       /*
+        * Any variable below the kref is valid before a tty is connected and
+        * stays valid after the tty is disconnected.  These shouldn't be
+        * whacked until the koject refcount reaches zero though some entries
+        * may be changed via sysfs initiatives.
+        */
+       struct kref kref; /* ref count & hvcs_struct lifetime */
+       int connected; /* is the vty-server currently connected to a vty? */
+       uint32_t p_unit_address; /* partner unit address */
+       uint32_t p_partition_ID; /* partner partition ID */
+       char p_location_code[HVCS_CLC_LENGTH + 1]; /* CLC + Null Term */
+       struct list_head next; /* list management */
+       struct vio_dev *vdev;
+};
+
+/* Required to back map a kref to its containing object */
+#define from_kref(k) container_of(k, struct hvcs_struct, kref)
+
+static LIST_HEAD(hvcs_structs);
+static DEFINE_SPINLOCK(hvcs_structs_lock);
+
+static void hvcs_unthrottle(struct tty_struct *tty);
+static void hvcs_throttle(struct tty_struct *tty);
+static irqreturn_t hvcs_handle_interrupt(int irq, void *dev_instance);
+
+static int hvcs_write(struct tty_struct *tty,
+               const unsigned char *buf, int count);
+static int hvcs_write_room(struct tty_struct *tty);
+static int hvcs_chars_in_buffer(struct tty_struct *tty);
+
+static int hvcs_has_pi(struct hvcs_struct *hvcsd);
+static void hvcs_set_pi(struct hvcs_partner_info *pi,
+               struct hvcs_struct *hvcsd);
+static int hvcs_get_pi(struct hvcs_struct *hvcsd);
+static int hvcs_rescan_devices_list(void);
+
+static int hvcs_partner_connect(struct hvcs_struct *hvcsd);
+static void hvcs_partner_free(struct hvcs_struct *hvcsd);
+
+static int hvcs_enable_device(struct hvcs_struct *hvcsd,
+               uint32_t unit_address, unsigned int irq, struct vio_dev *dev);
+
+static int hvcs_open(struct tty_struct *tty, struct file *filp);
+static void hvcs_close(struct tty_struct *tty, struct file *filp);
+static void hvcs_hangup(struct tty_struct * tty);
+
+static int __devinit hvcs_probe(struct vio_dev *dev,
+               const struct vio_device_id *id);
+static int __devexit hvcs_remove(struct vio_dev *dev);
+static int __init hvcs_module_init(void);
+static void __exit hvcs_module_exit(void);
+
+#define HVCS_SCHED_READ        0x00000001
+#define HVCS_QUICK_READ        0x00000002
+#define HVCS_TRY_WRITE 0x00000004
+#define HVCS_READ_MASK (HVCS_SCHED_READ | HVCS_QUICK_READ)
+
+static inline struct hvcs_struct *from_vio_dev(struct vio_dev *viod)
+{
+       return dev_get_drvdata(&viod->dev);
+}
+/* The sysfs interface for the driver and devices */
+
+static ssize_t hvcs_partner_vtys_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+       struct vio_dev *viod = to_vio_dev(dev);
+       struct hvcs_struct *hvcsd = from_vio_dev(viod);
+       unsigned long flags;
+       int retval;
+
+       spin_lock_irqsave(&hvcsd->lock, flags);
+       retval = sprintf(buf, "%X\n", hvcsd->p_unit_address);
+       spin_unlock_irqrestore(&hvcsd->lock, flags);
+       return retval;
+}
+static DEVICE_ATTR(partner_vtys, S_IRUGO, hvcs_partner_vtys_show, NULL);
+
+static ssize_t hvcs_partner_clcs_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+       struct vio_dev *viod = to_vio_dev(dev);
+       struct hvcs_struct *hvcsd = from_vio_dev(viod);
+       unsigned long flags;
+       int retval;
+
+       spin_lock_irqsave(&hvcsd->lock, flags);
+       retval = sprintf(buf, "%s\n", &hvcsd->p_location_code[0]);
+       spin_unlock_irqrestore(&hvcsd->lock, flags);
+       return retval;
+}
+static DEVICE_ATTR(partner_clcs, S_IRUGO, hvcs_partner_clcs_show, NULL);
+
+static ssize_t hvcs_current_vty_store(struct device *dev, struct device_attribute *attr, const char * buf,
+               size_t count)
+{
+       /*
+        * Don't need this feature at the present time because firmware doesn't
+        * yet support multiple partners.
+        */
+       printk(KERN_INFO "HVCS: Denied current_vty change: -EPERM.\n");
+       return -EPERM;
+}
+
+static ssize_t hvcs_current_vty_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+       struct vio_dev *viod = to_vio_dev(dev);
+       struct hvcs_struct *hvcsd = from_vio_dev(viod);
+       unsigned long flags;
+       int retval;
+
+       spin_lock_irqsave(&hvcsd->lock, flags);
+       retval = sprintf(buf, "%s\n", &hvcsd->p_location_code[0]);
+       spin_unlock_irqrestore(&hvcsd->lock, flags);
+       return retval;
+}
+
+static DEVICE_ATTR(current_vty,
+       S_IRUGO | S_IWUSR, hvcs_current_vty_show, hvcs_current_vty_store);
+
+static ssize_t hvcs_vterm_state_store(struct device *dev, struct device_attribute *attr, const char *buf,
+               size_t count)
+{
+       struct vio_dev *viod = to_vio_dev(dev);
+       struct hvcs_struct *hvcsd = from_vio_dev(viod);
+       unsigned long flags;
+
+       /* writing a '0' to this sysfs entry will result in the disconnect. */
+       if (simple_strtol(buf, NULL, 0) != 0)
+               return -EINVAL;
+
+       spin_lock_irqsave(&hvcsd->lock, flags);
+
+       if (hvcsd->open_count > 0) {
+               spin_unlock_irqrestore(&hvcsd->lock, flags);
+               printk(KERN_INFO "HVCS: vterm state unchanged.  "
+                               "The hvcs device node is still in use.\n");
+               return -EPERM;
+       }
+
+       if (hvcsd->connected == 0) {
+               spin_unlock_irqrestore(&hvcsd->lock, flags);
+               printk(KERN_INFO "HVCS: vterm state unchanged. The"
+                               " vty-server is not connected to a vty.\n");
+               return -EPERM;
+       }
+
+       hvcs_partner_free(hvcsd);
+       printk(KERN_INFO "HVCS: Closed vty-server@%X and"
+                       " partner vty@%X:%d connection.\n",
+                       hvcsd->vdev->unit_address,
+                       hvcsd->p_unit_address,
+                       (uint32_t)hvcsd->p_partition_ID);
+
+       spin_unlock_irqrestore(&hvcsd->lock, flags);
+       return count;
+}
+
+static ssize_t hvcs_vterm_state_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+       struct vio_dev *viod = to_vio_dev(dev);
+       struct hvcs_struct *hvcsd = from_vio_dev(viod);
+       unsigned long flags;
+       int retval;
+
+       spin_lock_irqsave(&hvcsd->lock, flags);
+       retval = sprintf(buf, "%d\n", hvcsd->connected);
+       spin_unlock_irqrestore(&hvcsd->lock, flags);
+       return retval;
+}
+static DEVICE_ATTR(vterm_state, S_IRUGO | S_IWUSR,
+               hvcs_vterm_state_show, hvcs_vterm_state_store);
+
+static ssize_t hvcs_index_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+       struct vio_dev *viod = to_vio_dev(dev);
+       struct hvcs_struct *hvcsd = from_vio_dev(viod);
+       unsigned long flags;
+       int retval;
+
+       spin_lock_irqsave(&hvcsd->lock, flags);
+       retval = sprintf(buf, "%d\n", hvcsd->index);
+       spin_unlock_irqrestore(&hvcsd->lock, flags);
+       return retval;
+}
+
+static DEVICE_ATTR(index, S_IRUGO, hvcs_index_show, NULL);
+
+static struct attribute *hvcs_attrs[] = {
+       &dev_attr_partner_vtys.attr,
+       &dev_attr_partner_clcs.attr,
+       &dev_attr_current_vty.attr,
+       &dev_attr_vterm_state.attr,
+       &dev_attr_index.attr,
+       NULL,
+};
+
+static struct attribute_group hvcs_attr_group = {
+       .attrs = hvcs_attrs,
+};
+
+static ssize_t hvcs_rescan_show(struct device_driver *ddp, char *buf)
+{
+       /* A 1 means it is updating, a 0 means it is done updating */
+       return snprintf(buf, PAGE_SIZE, "%d\n", hvcs_rescan_status);
+}
+
+static ssize_t hvcs_rescan_store(struct device_driver *ddp, const char * buf,
+               size_t count)
+{
+       if ((simple_strtol(buf, NULL, 0) != 1)
+               && (hvcs_rescan_status != 0))
+               return -EINVAL;
+
+       hvcs_rescan_status = 1;
+       printk(KERN_INFO "HVCS: rescanning partner info for all"
+               " vty-servers.\n");
+       hvcs_rescan_devices_list();
+       hvcs_rescan_status = 0;
+       return count;
+}
+
+static DRIVER_ATTR(rescan,
+       S_IRUGO | S_IWUSR, hvcs_rescan_show, hvcs_rescan_store);
+
+static void hvcs_kick(void)
+{
+       hvcs_kicked = 1;
+       wmb();
+       wake_up_process(hvcs_task);
+}
+
+static void hvcs_unthrottle(struct tty_struct *tty)
+{
+       struct hvcs_struct *hvcsd = tty->driver_data;
+       unsigned long flags;
+
+       spin_lock_irqsave(&hvcsd->lock, flags);
+       hvcsd->todo_mask |= HVCS_SCHED_READ;
+       spin_unlock_irqrestore(&hvcsd->lock, flags);
+       hvcs_kick();
+}
+
+static void hvcs_throttle(struct tty_struct *tty)
+{
+       struct hvcs_struct *hvcsd = tty->driver_data;
+       unsigned long flags;
+
+       spin_lock_irqsave(&hvcsd->lock, flags);
+       vio_disable_interrupts(hvcsd->vdev);
+       spin_unlock_irqrestore(&hvcsd->lock, flags);
+}
+
+/*
+ * If the device is being removed we don't have to worry about this interrupt
+ * handler taking any further interrupts because they are disabled which means
+ * the hvcs_struct will always be valid in this handler.
+ */
+static irqreturn_t hvcs_handle_interrupt(int irq, void *dev_instance)
+{
+       struct hvcs_struct *hvcsd = dev_instance;
+
+       spin_lock(&hvcsd->lock);
+       vio_disable_interrupts(hvcsd->vdev);
+       hvcsd->todo_mask |= HVCS_SCHED_READ;
+       spin_unlock(&hvcsd->lock);
+       hvcs_kick();
+
+       return IRQ_HANDLED;
+}
+
+/* This function must be called with the hvcsd->lock held */
+static void hvcs_try_write(struct hvcs_struct *hvcsd)
+{
+       uint32_t unit_address = hvcsd->vdev->unit_address;
+       struct tty_struct *tty = hvcsd->tty;
+       int sent;
+
+       if (hvcsd->todo_mask & HVCS_TRY_WRITE) {
+               /* won't send partial writes */
+               sent = hvc_put_chars(unit_address,
+                               &hvcsd->buffer[0],
+                               hvcsd->chars_in_buffer );
+               if (sent > 0) {
+                       hvcsd->chars_in_buffer = 0;
+                       /* wmb(); */
+                       hvcsd->todo_mask &= ~(HVCS_TRY_WRITE);
+                       /* wmb(); */
+
+                       /*
+                        * We are still obligated to deliver the data to the
+                        * hypervisor even if the tty has been closed because
+                        * we commited to delivering it.  But don't try to wake
+                        * a non-existent tty.
+                        */
+                       if (tty) {
+                               tty_wakeup(tty);
+                       }
+               }
+       }
+}
+
+static int hvcs_io(struct hvcs_struct *hvcsd)
+{
+       uint32_t unit_address;
+       struct tty_struct *tty;
+       char buf[HVCS_BUFF_LEN] __ALIGNED__;
+       unsigned long flags;
+       int got = 0;
+
+       spin_lock_irqsave(&hvcsd->lock, flags);
+
+       unit_address = hvcsd->vdev->unit_address;
+       tty = hvcsd->tty;
+
+       hvcs_try_write(hvcsd);
+
+       if (!tty || test_bit(TTY_THROTTLED, &tty->flags)) {
+               hvcsd->todo_mask &= ~(HVCS_READ_MASK);
+               goto bail;
+       } else if (!(hvcsd->todo_mask & (HVCS_READ_MASK)))
+               goto bail;
+
+       /* remove the read masks */
+       hvcsd->todo_mask &= ~(HVCS_READ_MASK);
+
+       if (tty_buffer_request_room(tty, HVCS_BUFF_LEN) >= HVCS_BUFF_LEN) {
+               got = hvc_get_chars(unit_address,
+                               &buf[0],
+                               HVCS_BUFF_LEN);
+               tty_insert_flip_string(tty, buf, got);
+       }
+
+       /* Give the TTY time to process the data we just sent. */
+       if (got)
+               hvcsd->todo_mask |= HVCS_QUICK_READ;
+
+       spin_unlock_irqrestore(&hvcsd->lock, flags);
+       /* This is synch because tty->low_latency == 1 */
+       if(got)
+               tty_flip_buffer_push(tty);
+
+       if (!got) {
+               /* Do this _after_ the flip_buffer_push */
+               spin_lock_irqsave(&hvcsd->lock, flags);
+               vio_enable_interrupts(hvcsd->vdev);
+               spin_unlock_irqrestore(&hvcsd->lock, flags);
+       }
+
+       return hvcsd->todo_mask;
+
+ bail:
+       spin_unlock_irqrestore(&hvcsd->lock, flags);
+       return hvcsd->todo_mask;
+}
+
+static int khvcsd(void *unused)
+{
+       struct hvcs_struct *hvcsd;
+       int hvcs_todo_mask;
+
+       __set_current_state(TASK_RUNNING);
+
+       do {
+               hvcs_todo_mask = 0;
+               hvcs_kicked = 0;
+               wmb();
+
+               spin_lock(&hvcs_structs_lock);
+               list_for_each_entry(hvcsd, &hvcs_structs, next) {
+                       hvcs_todo_mask |= hvcs_io(hvcsd);
+               }
+               spin_unlock(&hvcs_structs_lock);
+
+               /*
+                * If any of the hvcs adapters want to try a write or quick read
+                * don't schedule(), yield a smidgen then execute the hvcs_io
+                * thread again for those that want the write.
+                */
+                if (hvcs_todo_mask & (HVCS_TRY_WRITE | HVCS_QUICK_READ)) {
+                       yield();
+                       continue;
+               }
+
+               set_current_state(TASK_INTERRUPTIBLE);
+               if (!hvcs_kicked)
+                       schedule();
+               __set_current_state(TASK_RUNNING);
+       } while (!kthread_should_stop());
+
+       return 0;
+}
+
+static struct vio_device_id hvcs_driver_table[] __devinitdata= {
+       {"serial-server", "hvterm2"},
+       { "", "" }
+};
+MODULE_DEVICE_TABLE(vio, hvcs_driver_table);
+
+static void hvcs_return_index(int index)
+{
+       /* Paranoia check */
+       if (!hvcs_index_list)
+               return;
+       if (index < 0 || index >= hvcs_index_count)
+               return;
+       if (hvcs_index_list[index] == -1)
+               return;
+       else
+               hvcs_index_list[index] = -1;
+}
+
+/* callback when the kref ref count reaches zero */
+static void destroy_hvcs_struct(struct kref *kref)
+{
+       struct hvcs_struct *hvcsd = from_kref(kref);
+       struct vio_dev *vdev;
+       unsigned long flags;
+
+       spin_lock(&hvcs_structs_lock);
+       spin_lock_irqsave(&hvcsd->lock, flags);
+
+       /* the list_del poisons the pointers */
+       list_del(&(hvcsd->next));
+
+       if (hvcsd->connected == 1) {
+               hvcs_partner_free(hvcsd);
+               printk(KERN_INFO "HVCS: Closed vty-server@%X and"
+                               " partner vty@%X:%d connection.\n",
+                               hvcsd->vdev->unit_address,
+                               hvcsd->p_unit_address,
+                               (uint32_t)hvcsd->p_partition_ID);
+       }
+       printk(KERN_INFO "HVCS: Destroyed hvcs_struct for vty-server@%X.\n",
+                       hvcsd->vdev->unit_address);
+
+       vdev = hvcsd->vdev;
+       hvcsd->vdev = NULL;
+
+       hvcsd->p_unit_address = 0;
+       hvcsd->p_partition_ID = 0;
+       hvcs_return_index(hvcsd->index);
+       memset(&hvcsd->p_location_code[0], 0x00, HVCS_CLC_LENGTH + 1);
+
+       spin_unlock_irqrestore(&hvcsd->lock, flags);
+       spin_unlock(&hvcs_structs_lock);
+
+       sysfs_remove_group(&vdev->dev.kobj, &hvcs_attr_group);
+
+       kfree(hvcsd);
+}
+
+static int hvcs_get_index(void)
+{
+       int i;
+       /* Paranoia check */
+       if (!hvcs_index_list) {
+               printk(KERN_ERR "HVCS: hvcs_index_list NOT valid!.\n");
+               return -EFAULT;
+       }
+       /* Find the numerically lowest first free index. */
+       for(i = 0; i < hvcs_index_count; i++) {
+               if (hvcs_index_list[i] == -1) {
+                       hvcs_index_list[i] = 0;
+                       return i;
+               }
+       }
+       return -1;
+}
+
+static int __devinit hvcs_probe(
+       struct vio_dev *dev,
+       const struct vio_device_id *id)
+{
+       struct hvcs_struct *hvcsd;
+       int index;
+       int retval;
+
+       if (!dev || !id) {
+               printk(KERN_ERR "HVCS: probed with invalid parameter.\n");
+               return -EPERM;
+       }
+
+       /* early to avoid cleanup on failure */
+       index = hvcs_get_index();
+       if (index < 0) {
+               return -EFAULT;
+       }
+
+       hvcsd = kzalloc(sizeof(*hvcsd), GFP_KERNEL);
+       if (!hvcsd)
+               return -ENODEV;
+
+
+       spin_lock_init(&hvcsd->lock);
+       /* Automatically incs the refcount the first time */
+       kref_init(&hvcsd->kref);
+
+       hvcsd->vdev = dev;
+       dev_set_drvdata(&dev->dev, hvcsd);
+
+       hvcsd->index = index;
+
+       /* hvcsd->index = ++hvcs_struct_count; */
+       hvcsd->chars_in_buffer = 0;
+       hvcsd->todo_mask = 0;
+       hvcsd->connected = 0;
+
+       /*
+        * This will populate the hvcs_struct's partner info fields for the
+        * first time.
+        */
+       if (hvcs_get_pi(hvcsd)) {
+               printk(KERN_ERR "HVCS: Failed to fetch partner"
+                       " info for vty-server@%X on device probe.\n",
+                       hvcsd->vdev->unit_address);
+       }
+
+       /*
+        * If a user app opens a tty that corresponds to this vty-server before
+        * the hvcs_struct has been added to the devices list then the user app
+        * will get -ENODEV.
+        */
+       spin_lock(&hvcs_structs_lock);
+       list_add_tail(&(hvcsd->next), &hvcs_structs);
+       spin_unlock(&hvcs_structs_lock);
+
+       retval = sysfs_create_group(&dev->dev.kobj, &hvcs_attr_group);
+       if (retval) {
+               printk(KERN_ERR "HVCS: Can't create sysfs attrs for vty-server@%X\n",
+                      hvcsd->vdev->unit_address);
+               return retval;
+       }
+
+       printk(KERN_INFO "HVCS: vty-server@%X added to the vio bus.\n", dev->unit_address);
+
+       /*
+        * DON'T enable interrupts here because there is no user to receive the
+        * data.
+        */
+       return 0;
+}
+
+static int __devexit hvcs_remove(struct vio_dev *dev)
+{
+       struct hvcs_struct *hvcsd = dev_get_drvdata(&dev->dev);
+       unsigned long flags;
+       struct tty_struct *tty;
+
+       if (!hvcsd)
+               return -ENODEV;
+
+       /* By this time the vty-server won't be getting any more interrupts */
+
+       spin_lock_irqsave(&hvcsd->lock, flags);
+
+       tty = hvcsd->tty;
+
+       spin_unlock_irqrestore(&hvcsd->lock, flags);
+
+       /*
+        * Let the last holder of this object cause it to be removed, which
+        * would probably be tty_hangup below.
+        */
+       kref_put(&hvcsd->kref, destroy_hvcs_struct);
+
+       /*
+        * The hangup is a scheduled function which will auto chain call
+        * hvcs_hangup.  The tty should always be valid at this time unless a
+        * simultaneous tty close already cleaned up the hvcs_struct.
+        */
+       if (tty)
+               tty_hangup(tty);
+
+       printk(KERN_INFO "HVCS: vty-server@%X removed from the"
+                       " vio bus.\n", dev->unit_address);
+       return 0;
+};
+
+static struct vio_driver hvcs_vio_driver = {
+       .id_table       = hvcs_driver_table,
+       .probe          = hvcs_probe,
+       .remove         = __devexit_p(hvcs_remove),
+       .driver         = {
+               .name   = hvcs_driver_name,
+               .owner  = THIS_MODULE,
+       }
+};
+
+/* Only called from hvcs_get_pi please */
+static void hvcs_set_pi(struct hvcs_partner_info *pi, struct hvcs_struct *hvcsd)
+{
+       int clclength;
+
+       hvcsd->p_unit_address = pi->unit_address;
+       hvcsd->p_partition_ID  = pi->partition_ID;
+       clclength = strlen(&pi->location_code[0]);
+       if (clclength > HVCS_CLC_LENGTH)
+               clclength = HVCS_CLC_LENGTH;
+
+       /* copy the null-term char too */
+       strncpy(&hvcsd->p_location_code[0],
+                       &pi->location_code[0], clclength + 1);
+}
+
+/*
+ * Traverse the list and add the partner info that is found to the hvcs_struct
+ * struct entry. NOTE: At this time I know that partner info will return a
+ * single entry but in the future there may be multiple partner info entries per
+ * vty-server and you'll want to zero out that list and reset it.  If for some
+ * reason you have an old version of this driver but there IS more than one
+ * partner info then hvcsd->p_* will hold the last partner info data from the
+ * firmware query.  A good way to update this code would be to replace the three
+ * partner info fields in hvcs_struct with a list of hvcs_partner_info
+ * instances.
+ *
+ * This function must be called with the hvcsd->lock held.
+ */
+static int hvcs_get_pi(struct hvcs_struct *hvcsd)
+{
+       struct hvcs_partner_info *pi;
+       uint32_t unit_address = hvcsd->vdev->unit_address;
+       struct list_head head;
+       int retval;
+
+       spin_lock(&hvcs_pi_lock);
+       if (!hvcs_pi_buff) {
+               spin_unlock(&hvcs_pi_lock);
+               return -EFAULT;
+       }
+       retval = hvcs_get_partner_info(unit_address, &head, hvcs_pi_buff);
+       spin_unlock(&hvcs_pi_lock);
+       if (retval) {
+               printk(KERN_ERR "HVCS: Failed to fetch partner"
+                       " info for vty-server@%x.\n", unit_address);
+               return retval;
+       }
+
+       /* nixes the values if the partner vty went away */
+       hvcsd->p_unit_address = 0;
+       hvcsd->p_partition_ID = 0;
+
+       list_for_each_entry(pi, &head, node)
+               hvcs_set_pi(pi, hvcsd);
+
+       hvcs_free_partner_info(&head);
+       return 0;
+}
+
+/*
+ * This function is executed by the driver "rescan" sysfs entry.  It shouldn't
+ * be executed elsewhere, in order to prevent deadlock issues.
+ */
+static int hvcs_rescan_devices_list(void)
+{
+       struct hvcs_struct *hvcsd;
+       unsigned long flags;
+
+       spin_lock(&hvcs_structs_lock);
+
+       list_for_each_entry(hvcsd, &hvcs_structs, next) {
+               spin_lock_irqsave(&hvcsd->lock, flags);
+               hvcs_get_pi(hvcsd);
+               spin_unlock_irqrestore(&hvcsd->lock, flags);
+       }
+
+       spin_unlock(&hvcs_structs_lock);
+
+       return 0;
+}
+
+/*
+ * Farm this off into its own function because it could be more complex once
+ * multiple partners support is added. This function should be called with
+ * the hvcsd->lock held.
+ */
+static int hvcs_has_pi(struct hvcs_struct *hvcsd)
+{
+       if ((!hvcsd->p_unit_address) || (!hvcsd->p_partition_ID))
+               return 0;
+       return 1;
+}
+
+/*
+ * NOTE: It is possible that the super admin removed a partner vty and then
+ * added a different vty as the new partner.
+ *
+ * This function must be called with the hvcsd->lock held.
+ */
+static int hvcs_partner_connect(struct hvcs_struct *hvcsd)
+{
+       int retval;
+       unsigned int unit_address = hvcsd->vdev->unit_address;
+
+       /*
+        * If there wasn't any pi when the device was added it doesn't meant
+        * there isn't any now.  This driver isn't notified when a new partner
+        * vty is added to a vty-server so we discover changes on our own.
+        * Please see comments in hvcs_register_connection() for justification
+        * of this bizarre code.
+        */
+       retval = hvcs_register_connection(unit_address,
+                       hvcsd->p_partition_ID,
+                       hvcsd->p_unit_address);
+       if (!retval) {
+               hvcsd->connected = 1;
+               return 0;
+       } else if (retval != -EINVAL)
+               return retval;
+
+       /*
+        * As per the spec re-get the pi and try again if -EINVAL after the
+        * first connection attempt.
+        */
+       if (hvcs_get_pi(hvcsd))
+               return -ENOMEM;
+
+       if (!hvcs_has_pi(hvcsd))
+               return -ENODEV;
+
+       retval = hvcs_register_connection(unit_address,
+                       hvcsd->p_partition_ID,
+                       hvcsd->p_unit_address);
+       if (retval != -EINVAL) {
+               hvcsd->connected = 1;
+               return retval;
+       }
+
+       /*
+        * EBUSY is the most likely scenario though the vty could have been
+        * removed or there really could be an hcall error due to the parameter
+        * data but thanks to ambiguous firmware return codes we can't really
+        * tell.
+        */
+       printk(KERN_INFO "HVCS: vty-server or partner"
+                       " vty is busy.  Try again later.\n");
+       return -EBUSY;
+}
+
+/* This function must be called with the hvcsd->lock held */
+static void hvcs_partner_free(struct hvcs_struct *hvcsd)
+{
+       int retval;
+       do {
+               retval = hvcs_free_connection(hvcsd->vdev->unit_address);
+       } while (retval == -EBUSY);
+       hvcsd->connected = 0;
+}
+
+/* This helper function must be called WITHOUT the hvcsd->lock held */
+static int hvcs_enable_device(struct hvcs_struct *hvcsd, uint32_t unit_address,
+               unsigned int irq, struct vio_dev *vdev)
+{
+       unsigned long flags;
+       int rc;
+
+       /*
+        * It is possible that the vty-server was removed between the time that
+        * the conn was registered and now.
+        */
+       if (!(rc = request_irq(irq, &hvcs_handle_interrupt,
+                               IRQF_DISABLED, "ibmhvcs", hvcsd))) {
+               /*
+                * It is possible the vty-server was removed after the irq was
+                * requested but before we have time to enable interrupts.
+                */
+               if (vio_enable_interrupts(vdev) == H_SUCCESS)
+                       return 0;
+               else {
+                       printk(KERN_ERR "HVCS: int enable failed for"
+                                       " vty-server@%X.\n", unit_address);
+                       free_irq(irq, hvcsd);
+               }
+       } else
+               printk(KERN_ERR "HVCS: irq req failed for"
+                               " vty-server@%X.\n", unit_address);
+
+       spin_lock_irqsave(&hvcsd->lock, flags);
+       hvcs_partner_free(hvcsd);
+       spin_unlock_irqrestore(&hvcsd->lock, flags);
+
+       return rc;
+
+}
+
+/*
+ * This always increments the kref ref count if the call is successful.
+ * Please remember to dec when you are done with the instance.
+ *
+ * NOTICE: Do NOT hold either the hvcs_struct.lock or hvcs_structs_lock when
+ * calling this function or you will get deadlock.
+ */
+static struct hvcs_struct *hvcs_get_by_index(int index)
+{
+       struct hvcs_struct *hvcsd = NULL;
+       unsigned long flags;
+
+       spin_lock(&hvcs_structs_lock);
+       /* We can immediately discard OOB requests */
+       if (index >= 0 && index < HVCS_MAX_SERVER_ADAPTERS) {
+               list_for_each_entry(hvcsd, &hvcs_structs, next) {
+                       spin_lock_irqsave(&hvcsd->lock, flags);
+                       if (hvcsd->index == index) {
+                               kref_get(&hvcsd->kref);
+                               spin_unlock_irqrestore(&hvcsd->lock, flags);
+                               spin_unlock(&hvcs_structs_lock);
+                               return hvcsd;
+                       }
+                       spin_unlock_irqrestore(&hvcsd->lock, flags);
+               }
+               hvcsd = NULL;
+       }
+
+       spin_unlock(&hvcs_structs_lock);
+       return hvcsd;
+}
+
+/*
+ * This is invoked via the tty_open interface when a user app connects to the
+ * /dev node.
+ */
+static int hvcs_open(struct tty_struct *tty, struct file *filp)
+{
+       struct hvcs_struct *hvcsd;
+       int rc, retval = 0;
+       unsigned long flags;
+       unsigned int irq;
+       struct vio_dev *vdev;
+       unsigned long unit_address;
+
+       if (tty->driver_data)
+               goto fast_open;
+
+       /*
+        * Is there a vty-server that shares the same index?
+        * This function increments the kref index.
+        */
+       if (!(hvcsd = hvcs_get_by_index(tty->index))) {
+               printk(KERN_WARNING "HVCS: open failed, no device associated"
+                               " with tty->index %d.\n", tty->index);
+               return -ENODEV;
+       }
+
+       spin_lock_irqsave(&hvcsd->lock, flags);
+
+       if (hvcsd->connected == 0)
+               if ((retval = hvcs_partner_connect(hvcsd)))
+                       goto error_release;
+
+       hvcsd->open_count = 1;
+       hvcsd->tty = tty;
+       tty->driver_data = hvcsd;
+
+       memset(&hvcsd->buffer[0], 0x00, HVCS_BUFF_LEN);
+
+       /*
+        * Save these in the spinlock for the enable operations that need them
+        * outside of the spinlock.
+        */
+       irq = hvcsd->vdev->irq;
+       vdev = hvcsd->vdev;
+       unit_address = hvcsd->vdev->unit_address;
+
+       hvcsd->todo_mask |= HVCS_SCHED_READ;
+       spin_unlock_irqrestore(&hvcsd->lock, flags);
+
+       /*
+        * This must be done outside of the spinlock because it requests irqs
+        * and will grab the spinlock and free the connection if it fails.
+        */
+       if (((rc = hvcs_enable_device(hvcsd, unit_address, irq, vdev)))) {
+               kref_put(&hvcsd->kref, destroy_hvcs_struct);
+               printk(KERN_WARNING "HVCS: enable device failed.\n");
+               return rc;
+       }
+
+       goto open_success;
+
+fast_open:
+       hvcsd = tty->driver_data;
+
+       spin_lock_irqsave(&hvcsd->lock, flags);
+       kref_get(&hvcsd->kref);
+       hvcsd->open_count++;
+       hvcsd->todo_mask |= HVCS_SCHED_READ;
+       spin_unlock_irqrestore(&hvcsd->lock, flags);
+
+open_success:
+       hvcs_kick();
+
+       printk(KERN_INFO "HVCS: vty-server@%X connection opened.\n",
+               hvcsd->vdev->unit_address );
+
+       return 0;
+
+error_release:
+       spin_unlock_irqrestore(&hvcsd->lock, flags);
+       kref_put(&hvcsd->kref, destroy_hvcs_struct);
+
+       printk(KERN_WARNING "HVCS: partner connect failed.\n");
+       return retval;
+}
+
+static void hvcs_close(struct tty_struct *tty, struct file *filp)
+{
+       struct hvcs_struct *hvcsd;
+       unsigned long flags;
+       int irq = NO_IRQ;
+
+       /*
+        * Is someone trying to close the file associated with this device after
+        * we have hung up?  If so tty->driver_data wouldn't be valid.
+        */
+       if (tty_hung_up_p(filp))
+               return;
+
+       /*
+        * No driver_data means that this close was probably issued after a
+        * failed hvcs_open by the tty layer's release_dev() api and we can just
+        * exit cleanly.
+        */
+       if (!tty->driver_data)
+               return;
+
+       hvcsd = tty->driver_data;
+
+       spin_lock_irqsave(&hvcsd->lock, flags);
+       if (--hvcsd->open_count == 0) {
+
+               vio_disable_interrupts(hvcsd->vdev);
+
+               /*
+                * NULL this early so that the kernel_thread doesn't try to
+                * execute any operations on the TTY even though it is obligated
+                * to deliver any pending I/O to the hypervisor.
+                */
+               hvcsd->tty = NULL;
+
+               irq = hvcsd->vdev->irq;
+               spin_unlock_irqrestore(&hvcsd->lock, flags);
+
+               tty_wait_until_sent(tty, HVCS_CLOSE_WAIT);
+
+               /*
+                * This line is important because it tells hvcs_open that this
+                * device needs to be re-configured the next time hvcs_open is
+                * called.
+                */
+               tty->driver_data = NULL;
+
+               free_irq(irq, hvcsd);
+               kref_put(&hvcsd->kref, destroy_hvcs_struct);
+               return;
+       } else if (hvcsd->open_count < 0) {
+               printk(KERN_ERR "HVCS: vty-server@%X open_count: %d"
+                               " is missmanaged.\n",
+               hvcsd->vdev->unit_address, hvcsd->open_count);
+       }
+
+       spin_unlock_irqrestore(&hvcsd->lock, flags);
+       kref_put(&hvcsd->kref, destroy_hvcs_struct);
+}
+
+static void hvcs_hangup(struct tty_struct * tty)
+{
+       struct hvcs_struct *hvcsd = tty->driver_data;
+       unsigned long flags;
+       int temp_open_count;
+       int irq = NO_IRQ;
+
+       spin_lock_irqsave(&hvcsd->lock, flags);
+       /* Preserve this so that we know how many kref refs to put */
+       temp_open_count = hvcsd->open_count;
+
+       /*
+        * Don't kref put inside the spinlock because the destruction
+        * callback may use the spinlock and it may get called before the
+        * spinlock has been released.
+        */
+       vio_disable_interrupts(hvcsd->vdev);
+
+       hvcsd->todo_mask = 0;
+
+       /* I don't think the tty needs the hvcs_struct pointer after a hangup */
+       hvcsd->tty->driver_data = NULL;
+       hvcsd->tty = NULL;
+
+       hvcsd->open_count = 0;
+
+       /* This will drop any buffered data on the floor which is OK in a hangup
+        * scenario. */
+       memset(&hvcsd->buffer[0], 0x00, HVCS_BUFF_LEN);
+       hvcsd->chars_in_buffer = 0;
+
+       irq = hvcsd->vdev->irq;
+
+       spin_unlock_irqrestore(&hvcsd->lock, flags);
+
+       free_irq(irq, hvcsd);
+
+       /*
+        * We need to kref_put() for every open_count we have since the
+        * tty_hangup() function doesn't invoke a close per open connection on a
+        * non-console device.
+        */
+       while(temp_open_count) {
+               --temp_open_count;
+               /*
+                * The final put will trigger destruction of the hvcs_struct.
+                * NOTE:  If this hangup was signaled from user space then the
+                * final put will never happen.
+                */
+               kref_put(&hvcsd->kref, destroy_hvcs_struct);
+       }
+}
+
+/*
+ * NOTE: This is almost always from_user since user level apps interact with the
+ * /dev nodes. I'm trusting that if hvcs_write gets called and interrupted by
+ * hvcs_remove (which removes the target device and executes tty_hangup()) that
+ * tty_hangup will allow hvcs_write time to complete execution before it
+ * terminates our device.
+ */
+static int hvcs_write(struct tty_struct *tty,
+               const unsigned char *buf, int count)
+{
+       struct hvcs_struct *hvcsd = tty->driver_data;
+       unsigned int unit_address;
+       const unsigned char *charbuf;
+       unsigned long flags;
+       int total_sent = 0;
+       int tosend = 0;
+       int result = 0;
+
+       /*
+        * If they don't check the return code off of their open they may
+        * attempt this even if there is no connected device.
+        */
+       if (!hvcsd)
+               return -ENODEV;
+
+       /* Reasonable size to prevent user level flooding */
+       if (count > HVCS_MAX_FROM_USER) {
+               printk(KERN_WARNING "HVCS write: count being truncated to"
+                               " HVCS_MAX_FROM_USER.\n");
+               count = HVCS_MAX_FROM_USER;
+       }
+
+       charbuf = buf;
+
+       spin_lock_irqsave(&hvcsd->lock, flags);
+
+       /*
+        * Somehow an open succedded but the device was removed or the
+        * connection terminated between the vty-server and partner vty during
+        * the middle of a write operation?  This is a crummy place to do this
+        * but we want to keep it all in the spinlock.
+        */
+       if (hvcsd->open_count <= 0) {
+               spin_unlock_irqrestore(&hvcsd->lock, flags);
+               return -ENODEV;
+       }
+
+       unit_address = hvcsd->vdev->unit_address;
+
+       while (count > 0) {
+               tosend = min(count, (HVCS_BUFF_LEN - hvcsd->chars_in_buffer));
+               /*
+                * No more space, this probably means that the last call to
+                * hvcs_write() didn't succeed and the buffer was filled up.
+                */
+               if (!tosend)
+                       break;
+
+               memcpy(&hvcsd->buffer[hvcsd->chars_in_buffer],
+                               &charbuf[total_sent],
+                               tosend);
+
+               hvcsd->chars_in_buffer += tosend;
+
+               result = 0;
+
+               /*
+                * If this is true then we don't want to try writing to the
+                * hypervisor because that is the kernel_threads job now.  We'll
+                * just add to the buffer.
+                */
+               if (!(hvcsd->todo_mask & HVCS_TRY_WRITE))
+                       /* won't send partial writes */
+                       result = hvc_put_chars(unit_address,
+                                       &hvcsd->buffer[0],
+                                       hvcsd->chars_in_buffer);
+
+               /*
+                * Since we know we have enough room in hvcsd->buffer for
+                * tosend we record that it was sent regardless of whether the
+                * hypervisor actually took it because we have it buffered.
+                */
+               total_sent+=tosend;
+               count-=tosend;
+               if (result == 0) {
+                       hvcsd->todo_mask |= HVCS_TRY_WRITE;
+                       hvcs_kick();
+                       break;
+               }
+
+               hvcsd->chars_in_buffer = 0;
+               /*
+                * Test after the chars_in_buffer reset otherwise this could
+                * deadlock our writes if hvc_put_chars fails.
+                */
+               if (result < 0)
+                       break;
+       }
+
+       spin_unlock_irqrestore(&hvcsd->lock, flags);
+
+       if (result == -1)
+               return -EIO;
+       else
+               return total_sent;
+}
+
+/*
+ * This is really asking how much can we guarentee that we can send or that we
+ * absolutely WILL BUFFER if we can't send it.  This driver MUST honor the
+ * return value, hence the reason for hvcs_struct buffering.
+ */
+static int hvcs_write_room(struct tty_struct *tty)
+{
+       struct hvcs_struct *hvcsd = tty->driver_data;
+
+       if (!hvcsd || hvcsd->open_count <= 0)
+               return 0;
+
+       return HVCS_BUFF_LEN - hvcsd->chars_in_buffer;
+}
+
+static int hvcs_chars_in_buffer(struct tty_struct *tty)
+{
+       struct hvcs_struct *hvcsd = tty->driver_data;
+
+       return hvcsd->chars_in_buffer;
+}
+
+static const struct tty_operations hvcs_ops = {
+       .open = hvcs_open,
+       .close = hvcs_close,
+       .hangup = hvcs_hangup,
+       .write = hvcs_write,
+       .write_room = hvcs_write_room,
+       .chars_in_buffer = hvcs_chars_in_buffer,
+       .unthrottle = hvcs_unthrottle,
+       .throttle = hvcs_throttle,
+};
+
+static int hvcs_alloc_index_list(int n)
+{
+       int i;
+
+       hvcs_index_list = kmalloc(n * sizeof(hvcs_index_count),GFP_KERNEL);
+       if (!hvcs_index_list)
+               return -ENOMEM;
+       hvcs_index_count = n;
+       for (i = 0; i < hvcs_index_count; i++)
+               hvcs_index_list[i] = -1;
+       return 0;
+}
+
+static void hvcs_free_index_list(void)
+{
+       /* Paranoia check to be thorough. */
+       kfree(hvcs_index_list);
+       hvcs_index_list = NULL;
+       hvcs_index_count = 0;
+}
+
+static int __init hvcs_module_init(void)
+{
+       int rc;
+       int num_ttys_to_alloc;
+
+       printk(KERN_INFO "Initializing %s\n", hvcs_driver_string);
+
+       /* Has the user specified an overload with an insmod param? */
+       if (hvcs_parm_num_devs <= 0 ||
+               (hvcs_parm_num_devs > HVCS_MAX_SERVER_ADAPTERS)) {
+               num_ttys_to_alloc = HVCS_DEFAULT_SERVER_ADAPTERS;
+       } else
+               num_ttys_to_alloc = hvcs_parm_num_devs;
+
+       hvcs_tty_driver = alloc_tty_driver(num_ttys_to_alloc);
+       if (!hvcs_tty_driver)
+               return -ENOMEM;
+
+       if (hvcs_alloc_index_list(num_ttys_to_alloc)) {
+               rc = -ENOMEM;
+               goto index_fail;
+       }
+
+       hvcs_tty_driver->owner = THIS_MODULE;
+
+       hvcs_tty_driver->driver_name = hvcs_driver_name;
+       hvcs_tty_driver->name = hvcs_device_node;
+
+       /*
+        * We'll let the system assign us a major number, indicated by leaving
+        * it blank.
+        */
+
+       hvcs_tty_driver->minor_start = HVCS_MINOR_START;
+       hvcs_tty_driver->type = TTY_DRIVER_TYPE_SYSTEM;
+
+       /*
+        * We role our own so that we DONT ECHO.  We can't echo because the
+        * device we are connecting to already echoes by default and this would
+        * throw us into a horrible recursive echo-echo-echo loop.
+        */
+       hvcs_tty_driver->init_termios = hvcs_tty_termios;
+       hvcs_tty_driver->flags = TTY_DRIVER_REAL_RAW;
+
+       tty_set_operations(hvcs_tty_driver, &hvcs_ops);
+
+       /*
+        * The following call will result in sysfs entries that denote the
+        * dynamically assigned major and minor numbers for our devices.
+        */
+       if (tty_register_driver(hvcs_tty_driver)) {
+               printk(KERN_ERR "HVCS: registration as a tty driver failed.\n");
+               rc = -EIO;
+               goto register_fail;
+       }
+
+       hvcs_pi_buff = kmalloc(PAGE_SIZE, GFP_KERNEL);
+       if (!hvcs_pi_buff) {
+               rc = -ENOMEM;
+               goto buff_alloc_fail;
+       }
+
+       hvcs_task = kthread_run(khvcsd, NULL, "khvcsd");
+       if (IS_ERR(hvcs_task)) {
+               printk(KERN_ERR "HVCS: khvcsd creation failed.  Driver not loaded.\n");
+               rc = -EIO;
+               goto kthread_fail;
+       }
+
+       rc = vio_register_driver(&hvcs_vio_driver);
+       if (rc) {
+               printk(KERN_ERR "HVCS: can't register vio driver\n");
+               goto vio_fail;
+       }
+
+       /*
+        * This needs to be done AFTER the vio_register_driver() call or else
+        * the kobjects won't be initialized properly.
+        */
+       rc = driver_create_file(&(hvcs_vio_driver.driver), &driver_attr_rescan);
+       if (rc) {
+               printk(KERN_ERR "HVCS: sysfs attr create failed\n");
+               goto attr_fail;
+       }
+
+       printk(KERN_INFO "HVCS: driver module inserted.\n");
+
+       return 0;
+
+attr_fail:
+       vio_unregister_driver(&hvcs_vio_driver);
+vio_fail:
+       kthread_stop(hvcs_task);
+kthread_fail:
+       kfree(hvcs_pi_buff);
+buff_alloc_fail:
+       tty_unregister_driver(hvcs_tty_driver);
+register_fail:
+       hvcs_free_index_list();
+index_fail:
+       put_tty_driver(hvcs_tty_driver);
+       hvcs_tty_driver = NULL;
+       return rc;
+}
+
+static void __exit hvcs_module_exit(void)
+{
+       /*
+        * This driver receives hvcs_remove callbacks for each device upon
+        * module removal.
+        */
+
+       /*
+        * This synchronous operation  will wake the khvcsd kthread if it is
+        * asleep and will return when khvcsd has terminated.
+        */
+       kthread_stop(hvcs_task);
+
+       spin_lock(&hvcs_pi_lock);
+       kfree(hvcs_pi_buff);
+       hvcs_pi_buff = NULL;
+       spin_unlock(&hvcs_pi_lock);
+
+       driver_remove_file(&hvcs_vio_driver.driver, &driver_attr_rescan);
+
+       vio_unregister_driver(&hvcs_vio_driver);
+
+       tty_unregister_driver(hvcs_tty_driver);
+
+       hvcs_free_index_list();
+
+       put_tty_driver(hvcs_tty_driver);
+
+       printk(KERN_INFO "HVCS: driver module removed.\n");
+}
+
+module_init(hvcs_module_init);
+module_exit(hvcs_module_exit);
diff --git a/drivers/tty/hvc/hvsi.c b/drivers/tty/hvc/hvsi.c
new file mode 100644 (file)
index 0000000..67a75a5
--- /dev/null
@@ -0,0 +1,1314 @@
+/*
+ * Copyright (C) 2004 Hollis Blanchard <hollisb@us.ibm.com>, IBM
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
+ */
+
+/* Host Virtual Serial Interface (HVSI) is a protocol between the hosted OS
+ * and the service processor on IBM pSeries servers. On these servers, there
+ * are no serial ports under the OS's control, and sometimes there is no other
+ * console available either. However, the service processor has two standard
+ * serial ports, so this over-complicated protocol allows the OS to control
+ * those ports by proxy.
+ *
+ * Besides data, the procotol supports the reading/writing of the serial
+ * port's DTR line, and the reading of the CD line. This is to allow the OS to
+ * control a modem attached to the service processor's serial port. Note that
+ * the OS cannot change the speed of the port through this protocol.
+ */
+
+#undef DEBUG
+
+#include <linux/console.h>
+#include <linux/ctype.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/major.h>
+#include <linux/kernel.h>
+#include <linux/spinlock.h>
+#include <linux/sysrq.h>
+#include <linux/tty.h>
+#include <linux/tty_flip.h>
+#include <asm/hvcall.h>
+#include <asm/hvconsole.h>
+#include <asm/prom.h>
+#include <asm/uaccess.h>
+#include <asm/vio.h>
+#include <asm/param.h>
+
+#define HVSI_MAJOR     229
+#define HVSI_MINOR     128
+#define MAX_NR_HVSI_CONSOLES 4
+
+#define HVSI_TIMEOUT (5*HZ)
+#define HVSI_VERSION 1
+#define HVSI_MAX_PACKET 256
+#define HVSI_MAX_READ 16
+#define HVSI_MAX_OUTGOING_DATA 12
+#define N_OUTBUF 12
+
+/*
+ * we pass data via two 8-byte registers, so we would like our char arrays
+ * properly aligned for those loads.
+ */
+#define __ALIGNED__    __attribute__((__aligned__(sizeof(long))))
+
+struct hvsi_struct {
+       struct delayed_work writer;
+       struct work_struct handshaker;
+       wait_queue_head_t emptyq; /* woken when outbuf is emptied */
+       wait_queue_head_t stateq; /* woken when HVSI state changes */
+       spinlock_t lock;
+       int index;
+       struct tty_struct *tty;
+       int count;
+       uint8_t throttle_buf[128];
+       uint8_t outbuf[N_OUTBUF]; /* to implement write_room and chars_in_buffer */
+       /* inbuf is for packet reassembly. leave a little room for leftovers. */
+       uint8_t inbuf[HVSI_MAX_PACKET + HVSI_MAX_READ];
+       uint8_t *inbuf_end;
+       int n_throttle;
+       int n_outbuf;
+       uint32_t vtermno;
+       uint32_t virq;
+       atomic_t seqno; /* HVSI packet sequence number */
+       uint16_t mctrl;
+       uint8_t state;  /* HVSI protocol state */
+       uint8_t flags;
+#ifdef CONFIG_MAGIC_SYSRQ
+       uint8_t sysrq;
+#endif /* CONFIG_MAGIC_SYSRQ */
+};
+static struct hvsi_struct hvsi_ports[MAX_NR_HVSI_CONSOLES];
+
+static struct tty_driver *hvsi_driver;
+static int hvsi_count;
+static int (*hvsi_wait)(struct hvsi_struct *hp, int state);
+
+enum HVSI_PROTOCOL_STATE {
+       HVSI_CLOSED,
+       HVSI_WAIT_FOR_VER_RESPONSE,
+       HVSI_WAIT_FOR_VER_QUERY,
+       HVSI_OPEN,
+       HVSI_WAIT_FOR_MCTRL_RESPONSE,
+       HVSI_FSP_DIED,
+};
+#define HVSI_CONSOLE 0x1
+
+#define VS_DATA_PACKET_HEADER           0xff
+#define VS_CONTROL_PACKET_HEADER        0xfe
+#define VS_QUERY_PACKET_HEADER          0xfd
+#define VS_QUERY_RESPONSE_PACKET_HEADER 0xfc
+
+/* control verbs */
+#define VSV_SET_MODEM_CTL    1 /* to service processor only */
+#define VSV_MODEM_CTL_UPDATE 2 /* from service processor only */
+#define VSV_CLOSE_PROTOCOL   3
+
+/* query verbs */
+#define VSV_SEND_VERSION_NUMBER 1
+#define VSV_SEND_MODEM_CTL_STATUS 2
+
+/* yes, these masks are not consecutive. */
+#define HVSI_TSDTR 0x01
+#define HVSI_TSCD  0x20
+
+struct hvsi_header {
+       uint8_t  type;
+       uint8_t  len;
+       uint16_t seqno;
+} __attribute__((packed));
+
+struct hvsi_data {
+       uint8_t  type;
+       uint8_t  len;
+       uint16_t seqno;
+       uint8_t  data[HVSI_MAX_OUTGOING_DATA];
+} __attribute__((packed));
+
+struct hvsi_control {
+       uint8_t  type;
+       uint8_t  len;
+       uint16_t seqno;
+       uint16_t verb;
+       /* optional depending on verb: */
+       uint32_t word;
+       uint32_t mask;
+} __attribute__((packed));
+
+struct hvsi_query {
+       uint8_t  type;
+       uint8_t  len;
+       uint16_t seqno;
+       uint16_t verb;
+} __attribute__((packed));
+
+struct hvsi_query_response {
+       uint8_t  type;
+       uint8_t  len;
+       uint16_t seqno;
+       uint16_t verb;
+       uint16_t query_seqno;
+       union {
+               uint8_t  version;
+               uint32_t mctrl_word;
+       } u;
+} __attribute__((packed));
+
+
+
+static inline int is_console(struct hvsi_struct *hp)
+{
+       return hp->flags & HVSI_CONSOLE;
+}
+
+static inline int is_open(struct hvsi_struct *hp)
+{
+       /* if we're waiting for an mctrl then we're already open */
+       return (hp->state == HVSI_OPEN)
+                       || (hp->state == HVSI_WAIT_FOR_MCTRL_RESPONSE);
+}
+
+static inline void print_state(struct hvsi_struct *hp)
+{
+#ifdef DEBUG
+       static const char *state_names[] = {
+               "HVSI_CLOSED",
+               "HVSI_WAIT_FOR_VER_RESPONSE",
+               "HVSI_WAIT_FOR_VER_QUERY",
+               "HVSI_OPEN",
+               "HVSI_WAIT_FOR_MCTRL_RESPONSE",
+               "HVSI_FSP_DIED",
+       };
+       const char *name = (hp->state < ARRAY_SIZE(state_names))
+               ? state_names[hp->state] : "UNKNOWN";
+
+       pr_debug("hvsi%i: state = %s\n", hp->index, name);
+#endif /* DEBUG */
+}
+
+static inline void __set_state(struct hvsi_struct *hp, int state)
+{
+       hp->state = state;
+       print_state(hp);
+       wake_up_all(&hp->stateq);
+}
+
+static inline void set_state(struct hvsi_struct *hp, int state)
+{
+       unsigned long flags;
+
+       spin_lock_irqsave(&hp->lock, flags);
+       __set_state(hp, state);
+       spin_unlock_irqrestore(&hp->lock, flags);
+}
+
+static inline int len_packet(const uint8_t *packet)
+{
+       return (int)((struct hvsi_header *)packet)->len;
+}
+
+static inline int is_header(const uint8_t *packet)
+{
+       struct hvsi_header *header = (struct hvsi_header *)packet;
+       return header->type >= VS_QUERY_RESPONSE_PACKET_HEADER;
+}
+
+static inline int got_packet(const struct hvsi_struct *hp, uint8_t *packet)
+{
+       if (hp->inbuf_end < packet + sizeof(struct hvsi_header))
+               return 0; /* don't even have the packet header */
+
+       if (hp->inbuf_end < (packet + len_packet(packet)))
+               return 0; /* don't have the rest of the packet */
+
+       return 1;
+}
+
+/* shift remaining bytes in packetbuf down */
+static void compact_inbuf(struct hvsi_struct *hp, uint8_t *read_to)
+{
+       int remaining = (int)(hp->inbuf_end - read_to);
+
+       pr_debug("%s: %i chars remain\n", __func__, remaining);
+
+       if (read_to != hp->inbuf)
+               memmove(hp->inbuf, read_to, remaining);
+
+       hp->inbuf_end = hp->inbuf + remaining;
+}
+
+#ifdef DEBUG
+#define dbg_dump_packet(packet) dump_packet(packet)
+#define dbg_dump_hex(data, len) dump_hex(data, len)
+#else
+#define dbg_dump_packet(packet) do { } while (0)
+#define dbg_dump_hex(data, len) do { } while (0)
+#endif
+
+static void dump_hex(const uint8_t *data, int len)
+{
+       int i;
+
+       printk("    ");
+       for (i=0; i < len; i++)
+               printk("%.2x", data[i]);
+
+       printk("\n    ");
+       for (i=0; i < len; i++) {
+               if (isprint(data[i]))
+                       printk("%c", data[i]);
+               else
+                       printk(".");
+       }
+       printk("\n");
+}
+
+static void dump_packet(uint8_t *packet)
+{
+       struct hvsi_header *header = (struct hvsi_header *)packet;
+
+       printk("type 0x%x, len %i, seqno %i:\n", header->type, header->len,
+                       header->seqno);
+
+       dump_hex(packet, header->len);
+}
+
+static int hvsi_read(struct hvsi_struct *hp, char *buf, int count)
+{
+       unsigned long got;
+
+       got = hvc_get_chars(hp->vtermno, buf, count);
+
+       return got;
+}
+
+static void hvsi_recv_control(struct hvsi_struct *hp, uint8_t *packet,
+       struct tty_struct **to_hangup, struct hvsi_struct **to_handshake)
+{
+       struct hvsi_control *header = (struct hvsi_control *)packet;
+
+       switch (header->verb) {
+               case VSV_MODEM_CTL_UPDATE:
+                       if ((header->word & HVSI_TSCD) == 0) {
+                               /* CD went away; no more connection */
+                               pr_debug("hvsi%i: CD dropped\n", hp->index);
+                               hp->mctrl &= TIOCM_CD;
+                               /* If userland hasn't done an open(2) yet, hp->tty is NULL. */
+                               if (hp->tty && !(hp->tty->flags & CLOCAL))
+                                       *to_hangup = hp->tty;
+                       }
+                       break;
+               case VSV_CLOSE_PROTOCOL:
+                       pr_debug("hvsi%i: service processor came back\n", hp->index);
+                       if (hp->state != HVSI_CLOSED) {
+                               *to_handshake = hp;
+                       }
+                       break;
+               default:
+                       printk(KERN_WARNING "hvsi%i: unknown HVSI control packet: ",
+                               hp->index);
+                       dump_packet(packet);
+                       break;
+       }
+}
+
+static void hvsi_recv_response(struct hvsi_struct *hp, uint8_t *packet)
+{
+       struct hvsi_query_response *resp = (struct hvsi_query_response *)packet;
+
+       switch (hp->state) {
+               case HVSI_WAIT_FOR_VER_RESPONSE:
+                       __set_state(hp, HVSI_WAIT_FOR_VER_QUERY);
+                       break;
+               case HVSI_WAIT_FOR_MCTRL_RESPONSE:
+                       hp->mctrl = 0;
+                       if (resp->u.mctrl_word & HVSI_TSDTR)
+                               hp->mctrl |= TIOCM_DTR;
+                       if (resp->u.mctrl_word & HVSI_TSCD)
+                               hp->mctrl |= TIOCM_CD;
+                       __set_state(hp, HVSI_OPEN);
+                       break;
+               default:
+                       printk(KERN_ERR "hvsi%i: unexpected query response: ", hp->index);
+                       dump_packet(packet);
+                       break;
+       }
+}
+
+/* respond to service processor's version query */
+static int hvsi_version_respond(struct hvsi_struct *hp, uint16_t query_seqno)
+{
+       struct hvsi_query_response packet __ALIGNED__;
+       int wrote;
+
+       packet.type = VS_QUERY_RESPONSE_PACKET_HEADER;
+       packet.len = sizeof(struct hvsi_query_response);
+       packet.seqno = atomic_inc_return(&hp->seqno);
+       packet.verb = VSV_SEND_VERSION_NUMBER;
+       packet.u.version = HVSI_VERSION;
+       packet.query_seqno = query_seqno+1;
+
+       pr_debug("%s: sending %i bytes\n", __func__, packet.len);
+       dbg_dump_hex((uint8_t*)&packet, packet.len);
+
+       wrote = hvc_put_chars(hp->vtermno, (char *)&packet, packet.len);
+       if (wrote != packet.len) {
+               printk(KERN_ERR "hvsi%i: couldn't send query response!\n",
+                       hp->index);
+               return -EIO;
+       }
+
+       return 0;
+}
+
+static void hvsi_recv_query(struct hvsi_struct *hp, uint8_t *packet)
+{
+       struct hvsi_query *query = (struct hvsi_query *)packet;
+
+       switch (hp->state) {
+               case HVSI_WAIT_FOR_VER_QUERY:
+                       hvsi_version_respond(hp, query->seqno);
+                       __set_state(hp, HVSI_OPEN);
+                       break;
+               default:
+                       printk(KERN_ERR "hvsi%i: unexpected query: ", hp->index);
+                       dump_packet(packet);
+                       break;
+       }
+}
+
+static void hvsi_insert_chars(struct hvsi_struct *hp, const char *buf, int len)
+{
+       int i;
+
+       for (i=0; i < len; i++) {
+               char c = buf[i];
+#ifdef CONFIG_MAGIC_SYSRQ
+               if (c == '\0') {
+                       hp->sysrq = 1;
+                       continue;
+               } else if (hp->sysrq) {
+                       handle_sysrq(c);
+                       hp->sysrq = 0;
+                       continue;
+               }
+#endif /* CONFIG_MAGIC_SYSRQ */
+               tty_insert_flip_char(hp->tty, c, 0);
+       }
+}
+
+/*
+ * We could get 252 bytes of data at once here. But the tty layer only
+ * throttles us at TTY_THRESHOLD_THROTTLE (128) bytes, so we could overflow
+ * it. Accordingly we won't send more than 128 bytes at a time to the flip
+ * buffer, which will give the tty buffer a chance to throttle us. Should the
+ * value of TTY_THRESHOLD_THROTTLE change in n_tty.c, this code should be
+ * revisited.
+ */
+#define TTY_THRESHOLD_THROTTLE 128
+static struct tty_struct *hvsi_recv_data(struct hvsi_struct *hp,
+               const uint8_t *packet)
+{
+       const struct hvsi_header *header = (const struct hvsi_header *)packet;
+       const uint8_t *data = packet + sizeof(struct hvsi_header);
+       int datalen = header->len - sizeof(struct hvsi_header);
+       int overflow = datalen - TTY_THRESHOLD_THROTTLE;
+
+       pr_debug("queueing %i chars '%.*s'\n", datalen, datalen, data);
+
+       if (datalen == 0)
+               return NULL;
+
+       if (overflow > 0) {
+               pr_debug("%s: got >TTY_THRESHOLD_THROTTLE bytes\n", __func__);
+               datalen = TTY_THRESHOLD_THROTTLE;
+       }
+
+       hvsi_insert_chars(hp, data, datalen);
+
+       if (overflow > 0) {
+               /*
+                * we still have more data to deliver, so we need to save off the
+                * overflow and send it later
+                */
+               pr_debug("%s: deferring overflow\n", __func__);
+               memcpy(hp->throttle_buf, data + TTY_THRESHOLD_THROTTLE, overflow);
+               hp->n_throttle = overflow;
+       }
+
+       return hp->tty;
+}
+
+/*
+ * Returns true/false indicating data successfully read from hypervisor.
+ * Used both to get packets for tty connections and to advance the state
+ * machine during console handshaking (in which case tty = NULL and we ignore
+ * incoming data).
+ */
+static int hvsi_load_chunk(struct hvsi_struct *hp, struct tty_struct **flip,
+               struct tty_struct **hangup, struct hvsi_struct **handshake)
+{
+       uint8_t *packet = hp->inbuf;
+       int chunklen;
+
+       *flip = NULL;
+       *hangup = NULL;
+       *handshake = NULL;
+
+       chunklen = hvsi_read(hp, hp->inbuf_end, HVSI_MAX_READ);
+       if (chunklen == 0) {
+               pr_debug("%s: 0-length read\n", __func__);
+               return 0;
+       }
+
+       pr_debug("%s: got %i bytes\n", __func__, chunklen);
+       dbg_dump_hex(hp->inbuf_end, chunklen);
+
+       hp->inbuf_end += chunklen;
+
+       /* handle all completed packets */
+       while ((packet < hp->inbuf_end) && got_packet(hp, packet)) {
+               struct hvsi_header *header = (struct hvsi_header *)packet;
+
+               if (!is_header(packet)) {
+                       printk(KERN_ERR "hvsi%i: got malformed packet\n", hp->index);
+                       /* skip bytes until we find a header or run out of data */
+                       while ((packet < hp->inbuf_end) && (!is_header(packet)))
+                               packet++;
+                       continue;
+               }
+
+               pr_debug("%s: handling %i-byte packet\n", __func__,
+                               len_packet(packet));
+               dbg_dump_packet(packet);
+
+               switch (header->type) {
+                       case VS_DATA_PACKET_HEADER:
+                               if (!is_open(hp))
+                                       break;
+                               if (hp->tty == NULL)
+                                       break; /* no tty buffer to put data in */
+                               *flip = hvsi_recv_data(hp, packet);
+                               break;
+                       case VS_CONTROL_PACKET_HEADER:
+                               hvsi_recv_control(hp, packet, hangup, handshake);
+                               break;
+                       case VS_QUERY_RESPONSE_PACKET_HEADER:
+                               hvsi_recv_response(hp, packet);
+                               break;
+                       case VS_QUERY_PACKET_HEADER:
+                               hvsi_recv_query(hp, packet);
+                               break;
+                       default:
+                               printk(KERN_ERR "hvsi%i: unknown HVSI packet type 0x%x\n",
+                                               hp->index, header->type);
+                               dump_packet(packet);
+                               break;
+               }
+
+               packet += len_packet(packet);
+
+               if (*hangup || *handshake) {
+                       pr_debug("%s: hangup or handshake\n", __func__);
+                       /*
+                        * we need to send the hangup now before receiving any more data.
+                        * If we get "data, hangup, data", we can't deliver the second
+                        * data before the hangup.
+                        */
+                       break;
+               }
+       }
+
+       compact_inbuf(hp, packet);
+
+       return 1;
+}
+
+static void hvsi_send_overflow(struct hvsi_struct *hp)
+{
+       pr_debug("%s: delivering %i bytes overflow\n", __func__,
+                       hp->n_throttle);
+
+       hvsi_insert_chars(hp, hp->throttle_buf, hp->n_throttle);
+       hp->n_throttle = 0;
+}
+
+/*
+ * must get all pending data because we only get an irq on empty->non-empty
+ * transition
+ */
+static irqreturn_t hvsi_interrupt(int irq, void *arg)
+{
+       struct hvsi_struct *hp = (struct hvsi_struct *)arg;
+       struct tty_struct *flip;
+       struct tty_struct *hangup;
+       struct hvsi_struct *handshake;
+       unsigned long flags;
+       int again = 1;
+
+       pr_debug("%s\n", __func__);
+
+       while (again) {
+               spin_lock_irqsave(&hp->lock, flags);
+               again = hvsi_load_chunk(hp, &flip, &hangup, &handshake);
+               spin_unlock_irqrestore(&hp->lock, flags);
+
+               /*
+                * we have to call tty_flip_buffer_push() and tty_hangup() outside our
+                * spinlock. But we also have to keep going until we've read all the
+                * available data.
+                */
+
+               if (flip) {
+                       /* there was data put in the tty flip buffer */
+                       tty_flip_buffer_push(flip);
+                       flip = NULL;
+               }
+
+               if (hangup) {
+                       tty_hangup(hangup);
+               }
+
+               if (handshake) {
+                       pr_debug("hvsi%i: attempting re-handshake\n", handshake->index);
+                       schedule_work(&handshake->handshaker);
+               }
+       }
+
+       spin_lock_irqsave(&hp->lock, flags);
+       if (hp->tty && hp->n_throttle
+                       && (!test_bit(TTY_THROTTLED, &hp->tty->flags))) {
+               /* we weren't hung up and we weren't throttled, so we can deliver the
+                * rest now */
+               flip = hp->tty;
+               hvsi_send_overflow(hp);
+       }
+       spin_unlock_irqrestore(&hp->lock, flags);
+
+       if (flip) {
+               tty_flip_buffer_push(flip);
+       }
+
+       return IRQ_HANDLED;
+}
+
+/* for boot console, before the irq handler is running */
+static int __init poll_for_state(struct hvsi_struct *hp, int state)
+{
+       unsigned long end_jiffies = jiffies + HVSI_TIMEOUT;
+
+       for (;;) {
+               hvsi_interrupt(hp->virq, (void *)hp); /* get pending data */
+
+               if (hp->state == state)
+                       return 0;
+
+               mdelay(5);
+               if (time_after(jiffies, end_jiffies))
+                       return -EIO;
+       }
+}
+
+/* wait for irq handler to change our state */
+static int wait_for_state(struct hvsi_struct *hp, int state)
+{
+       int ret = 0;
+
+       if (!wait_event_timeout(hp->stateq, (hp->state == state), HVSI_TIMEOUT))
+               ret = -EIO;
+
+       return ret;
+}
+
+static int hvsi_query(struct hvsi_struct *hp, uint16_t verb)
+{
+       struct hvsi_query packet __ALIGNED__;
+       int wrote;
+
+       packet.type = VS_QUERY_PACKET_HEADER;
+       packet.len = sizeof(struct hvsi_query);
+       packet.seqno = atomic_inc_return(&hp->seqno);
+       packet.verb = verb;
+
+       pr_debug("%s: sending %i bytes\n", __func__, packet.len);
+       dbg_dump_hex((uint8_t*)&packet, packet.len);
+
+       wrote = hvc_put_chars(hp->vtermno, (char *)&packet, packet.len);
+       if (wrote != packet.len) {
+               printk(KERN_ERR "hvsi%i: couldn't send query (%i)!\n", hp->index,
+                       wrote);
+               return -EIO;
+       }
+
+       return 0;
+}
+
+static int hvsi_get_mctrl(struct hvsi_struct *hp)
+{
+       int ret;
+
+       set_state(hp, HVSI_WAIT_FOR_MCTRL_RESPONSE);
+       hvsi_query(hp, VSV_SEND_MODEM_CTL_STATUS);
+
+       ret = hvsi_wait(hp, HVSI_OPEN);
+       if (ret < 0) {
+               printk(KERN_ERR "hvsi%i: didn't get modem flags\n", hp->index);
+               set_state(hp, HVSI_OPEN);
+               return ret;
+       }
+
+       pr_debug("%s: mctrl 0x%x\n", __func__, hp->mctrl);
+
+       return 0;
+}
+
+/* note that we can only set DTR */
+static int hvsi_set_mctrl(struct hvsi_struct *hp, uint16_t mctrl)
+{
+       struct hvsi_control packet __ALIGNED__;
+       int wrote;
+
+       packet.type = VS_CONTROL_PACKET_HEADER,
+       packet.seqno = atomic_inc_return(&hp->seqno);
+       packet.len = sizeof(struct hvsi_control);
+       packet.verb = VSV_SET_MODEM_CTL;
+       packet.mask = HVSI_TSDTR;
+
+       if (mctrl & TIOCM_DTR)
+               packet.word = HVSI_TSDTR;
+
+       pr_debug("%s: sending %i bytes\n", __func__, packet.len);
+       dbg_dump_hex((uint8_t*)&packet, packet.len);
+
+       wrote = hvc_put_chars(hp->vtermno, (char *)&packet, packet.len);
+       if (wrote != packet.len) {
+               printk(KERN_ERR "hvsi%i: couldn't set DTR!\n", hp->index);
+               return -EIO;
+       }
+
+       return 0;
+}
+
+static void hvsi_drain_input(struct hvsi_struct *hp)
+{
+       uint8_t buf[HVSI_MAX_READ] __ALIGNED__;
+       unsigned long end_jiffies = jiffies + HVSI_TIMEOUT;
+
+       while (time_before(end_jiffies, jiffies))
+               if (0 == hvsi_read(hp, buf, HVSI_MAX_READ))
+                       break;
+}
+
+static int hvsi_handshake(struct hvsi_struct *hp)
+{
+       int ret;
+
+       /*
+        * We could have a CLOSE or other data waiting for us before we even try
+        * to open; try to throw it all away so we don't get confused. (CLOSE
+        * is the first message sent up the pipe when the FSP comes online. We
+        * need to distinguish between "it came up a while ago and we're the first
+        * user" and "it was just reset before it saw our handshake packet".)
+        */
+       hvsi_drain_input(hp);
+
+       set_state(hp, HVSI_WAIT_FOR_VER_RESPONSE);
+       ret = hvsi_query(hp, VSV_SEND_VERSION_NUMBER);
+       if (ret < 0) {
+               printk(KERN_ERR "hvsi%i: couldn't send version query\n", hp->index);
+               return ret;
+       }
+
+       ret = hvsi_wait(hp, HVSI_OPEN);
+       if (ret < 0)
+               return ret;
+
+       return 0;
+}
+
+static void hvsi_handshaker(struct work_struct *work)
+{
+       struct hvsi_struct *hp =
+               container_of(work, struct hvsi_struct, handshaker);
+
+       if (hvsi_handshake(hp) >= 0)
+               return;
+
+       printk(KERN_ERR "hvsi%i: re-handshaking failed\n", hp->index);
+       if (is_console(hp)) {
+               /*
+                * ttys will re-attempt the handshake via hvsi_open, but
+                * the console will not.
+                */
+               printk(KERN_ERR "hvsi%i: lost console!\n", hp->index);
+       }
+}
+
+static int hvsi_put_chars(struct hvsi_struct *hp, const char *buf, int count)
+{
+       struct hvsi_data packet __ALIGNED__;
+       int ret;
+
+       BUG_ON(count > HVSI_MAX_OUTGOING_DATA);
+
+       packet.type = VS_DATA_PACKET_HEADER;
+       packet.seqno = atomic_inc_return(&hp->seqno);
+       packet.len = count + sizeof(struct hvsi_header);
+       memcpy(&packet.data, buf, count);
+
+       ret = hvc_put_chars(hp->vtermno, (char *)&packet, packet.len);
+       if (ret == packet.len) {
+               /* return the number of chars written, not the packet length */
+               return count;
+       }
+       return ret; /* return any errors */
+}
+
+static void hvsi_close_protocol(struct hvsi_struct *hp)
+{
+       struct hvsi_control packet __ALIGNED__;
+
+       packet.type = VS_CONTROL_PACKET_HEADER;
+       packet.seqno = atomic_inc_return(&hp->seqno);
+       packet.len = 6;
+       packet.verb = VSV_CLOSE_PROTOCOL;
+
+       pr_debug("%s: sending %i bytes\n", __func__, packet.len);
+       dbg_dump_hex((uint8_t*)&packet, packet.len);
+
+       hvc_put_chars(hp->vtermno, (char *)&packet, packet.len);
+}
+
+static int hvsi_open(struct tty_struct *tty, struct file *filp)
+{
+       struct hvsi_struct *hp;
+       unsigned long flags;
+       int line = tty->index;
+       int ret;
+
+       pr_debug("%s\n", __func__);
+
+       if (line < 0 || line >= hvsi_count)
+               return -ENODEV;
+       hp = &hvsi_ports[line];
+
+       tty->driver_data = hp;
+
+       mb();
+       if (hp->state == HVSI_FSP_DIED)
+               return -EIO;
+
+       spin_lock_irqsave(&hp->lock, flags);
+       hp->tty = tty;
+       hp->count++;
+       atomic_set(&hp->seqno, 0);
+       h_vio_signal(hp->vtermno, VIO_IRQ_ENABLE);
+       spin_unlock_irqrestore(&hp->lock, flags);
+
+       if (is_console(hp))
+               return 0; /* this has already been handshaked as the console */
+
+       ret = hvsi_handshake(hp);
+       if (ret < 0) {
+               printk(KERN_ERR "%s: HVSI handshaking failed\n", tty->name);
+               return ret;
+       }
+
+       ret = hvsi_get_mctrl(hp);
+       if (ret < 0) {
+               printk(KERN_ERR "%s: couldn't get initial modem flags\n", tty->name);
+               return ret;
+       }
+
+       ret = hvsi_set_mctrl(hp, hp->mctrl | TIOCM_DTR);
+       if (ret < 0) {
+               printk(KERN_ERR "%s: couldn't set DTR\n", tty->name);
+               return ret;
+       }
+
+       return 0;
+}
+
+/* wait for hvsi_write_worker to empty hp->outbuf */
+static void hvsi_flush_output(struct hvsi_struct *hp)
+{
+       wait_event_timeout(hp->emptyq, (hp->n_outbuf <= 0), HVSI_TIMEOUT);
+
+       /* 'writer' could still be pending if it didn't see n_outbuf = 0 yet */
+       cancel_delayed_work_sync(&hp->writer);
+       flush_work_sync(&hp->handshaker);
+
+       /*
+        * it's also possible that our timeout expired and hvsi_write_worker
+        * didn't manage to push outbuf. poof.
+        */
+       hp->n_outbuf = 0;
+}
+
+static void hvsi_close(struct tty_struct *tty, struct file *filp)
+{
+       struct hvsi_struct *hp = tty->driver_data;
+       unsigned long flags;
+
+       pr_debug("%s\n", __func__);
+
+       if (tty_hung_up_p(filp))
+               return;
+
+       spin_lock_irqsave(&hp->lock, flags);
+
+       if (--hp->count == 0) {
+               hp->tty = NULL;
+               hp->inbuf_end = hp->inbuf; /* discard remaining partial packets */
+
+               /* only close down connection if it is not the console */
+               if (!is_console(hp)) {
+                       h_vio_signal(hp->vtermno, VIO_IRQ_DISABLE); /* no more irqs */
+                       __set_state(hp, HVSI_CLOSED);
+                       /*
+                        * any data delivered to the tty layer after this will be
+                        * discarded (except for XON/XOFF)
+                        */
+                       tty->closing = 1;
+
+                       spin_unlock_irqrestore(&hp->lock, flags);
+
+                       /* let any existing irq handlers finish. no more will start. */
+                       synchronize_irq(hp->virq);
+
+                       /* hvsi_write_worker will re-schedule until outbuf is empty. */
+                       hvsi_flush_output(hp);
+
+                       /* tell FSP to stop sending data */
+                       hvsi_close_protocol(hp);
+
+                       /*
+                        * drain anything FSP is still in the middle of sending, and let
+                        * hvsi_handshake drain the rest on the next open.
+                        */
+                       hvsi_drain_input(hp);
+
+                       spin_lock_irqsave(&hp->lock, flags);
+               }
+       } else if (hp->count < 0)
+               printk(KERN_ERR "hvsi_close %lu: oops, count is %d\n",
+                      hp - hvsi_ports, hp->count);
+
+       spin_unlock_irqrestore(&hp->lock, flags);
+}
+
+static void hvsi_hangup(struct tty_struct *tty)
+{
+       struct hvsi_struct *hp = tty->driver_data;
+       unsigned long flags;
+
+       pr_debug("%s\n", __func__);
+
+       spin_lock_irqsave(&hp->lock, flags);
+
+       hp->count = 0;
+       hp->n_outbuf = 0;
+       hp->tty = NULL;
+
+       spin_unlock_irqrestore(&hp->lock, flags);
+}
+
+/* called with hp->lock held */
+static void hvsi_push(struct hvsi_struct *hp)
+{
+       int n;
+
+       if (hp->n_outbuf <= 0)
+               return;
+
+       n = hvsi_put_chars(hp, hp->outbuf, hp->n_outbuf);
+       if (n > 0) {
+               /* success */
+               pr_debug("%s: wrote %i chars\n", __func__, n);
+               hp->n_outbuf = 0;
+       } else if (n == -EIO) {
+               __set_state(hp, HVSI_FSP_DIED);
+               printk(KERN_ERR "hvsi%i: service processor died\n", hp->index);
+       }
+}
+
+/* hvsi_write_worker will keep rescheduling itself until outbuf is empty */
+static void hvsi_write_worker(struct work_struct *work)
+{
+       struct hvsi_struct *hp =
+               container_of(work, struct hvsi_struct, writer.work);
+       unsigned long flags;
+#ifdef DEBUG
+       static long start_j = 0;
+
+       if (start_j == 0)
+               start_j = jiffies;
+#endif /* DEBUG */
+
+       spin_lock_irqsave(&hp->lock, flags);
+
+       pr_debug("%s: %i chars in buffer\n", __func__, hp->n_outbuf);
+
+       if (!is_open(hp)) {
+               /*
+                * We could have a non-open connection if the service processor died
+                * while we were busily scheduling ourselves. In that case, it could
+                * be minutes before the service processor comes back, so only try
+                * again once a second.
+                */
+               schedule_delayed_work(&hp->writer, HZ);
+               goto out;
+       }
+
+       hvsi_push(hp);
+       if (hp->n_outbuf > 0)
+               schedule_delayed_work(&hp->writer, 10);
+       else {
+#ifdef DEBUG
+               pr_debug("%s: outbuf emptied after %li jiffies\n", __func__,
+                               jiffies - start_j);
+               start_j = 0;
+#endif /* DEBUG */
+               wake_up_all(&hp->emptyq);
+               tty_wakeup(hp->tty);
+       }
+
+out:
+       spin_unlock_irqrestore(&hp->lock, flags);
+}
+
+static int hvsi_write_room(struct tty_struct *tty)
+{
+       struct hvsi_struct *hp = tty->driver_data;
+
+       return N_OUTBUF - hp->n_outbuf;
+}
+
+static int hvsi_chars_in_buffer(struct tty_struct *tty)
+{
+       struct hvsi_struct *hp = tty->driver_data;
+
+       return hp->n_outbuf;
+}
+
+static int hvsi_write(struct tty_struct *tty,
+                    const unsigned char *buf, int count)
+{
+       struct hvsi_struct *hp = tty->driver_data;
+       const char *source = buf;
+       unsigned long flags;
+       int total = 0;
+       int origcount = count;
+
+       spin_lock_irqsave(&hp->lock, flags);
+
+       pr_debug("%s: %i chars in buffer\n", __func__, hp->n_outbuf);
+
+       if (!is_open(hp)) {
+               /* we're either closing or not yet open; don't accept data */
+               pr_debug("%s: not open\n", __func__);
+               goto out;
+       }
+
+       /*
+        * when the hypervisor buffer (16K) fills, data will stay in hp->outbuf
+        * and hvsi_write_worker will be scheduled. subsequent hvsi_write() calls
+        * will see there is no room in outbuf and return.
+        */
+       while ((count > 0) && (hvsi_write_room(hp->tty) > 0)) {
+               int chunksize = min(count, hvsi_write_room(hp->tty));
+
+               BUG_ON(hp->n_outbuf < 0);
+               memcpy(hp->outbuf + hp->n_outbuf, source, chunksize);
+               hp->n_outbuf += chunksize;
+
+               total += chunksize;
+               source += chunksize;
+               count -= chunksize;
+               hvsi_push(hp);
+       }
+
+       if (hp->n_outbuf > 0) {
+               /*
+                * we weren't able to write it all to the hypervisor.
+                * schedule another push attempt.
+                */
+               schedule_delayed_work(&hp->writer, 10);
+       }
+
+out:
+       spin_unlock_irqrestore(&hp->lock, flags);
+
+       if (total != origcount)
+               pr_debug("%s: wanted %i, only wrote %i\n", __func__, origcount,
+                       total);
+
+       return total;
+}
+
+/*
+ * I have never seen throttle or unthrottle called, so this little throttle
+ * buffering scheme may or may not work.
+ */
+static void hvsi_throttle(struct tty_struct *tty)
+{
+       struct hvsi_struct *hp = tty->driver_data;
+
+       pr_debug("%s\n", __func__);
+
+       h_vio_signal(hp->vtermno, VIO_IRQ_DISABLE);
+}
+
+static void hvsi_unthrottle(struct tty_struct *tty)
+{
+       struct hvsi_struct *hp = tty->driver_data;
+       unsigned long flags;
+       int shouldflip = 0;
+
+       pr_debug("%s\n", __func__);
+
+       spin_lock_irqsave(&hp->lock, flags);
+       if (hp->n_throttle) {
+               hvsi_send_overflow(hp);
+               shouldflip = 1;
+       }
+       spin_unlock_irqrestore(&hp->lock, flags);
+
+       if (shouldflip)
+               tty_flip_buffer_push(hp->tty);
+
+       h_vio_signal(hp->vtermno, VIO_IRQ_ENABLE);
+}
+
+static int hvsi_tiocmget(struct tty_struct *tty, struct file *file)
+{
+       struct hvsi_struct *hp = tty->driver_data;
+
+       hvsi_get_mctrl(hp);
+       return hp->mctrl;
+}
+
+static int hvsi_tiocmset(struct tty_struct *tty, struct file *file,
+               unsigned int set, unsigned int clear)
+{
+       struct hvsi_struct *hp = tty->driver_data;
+       unsigned long flags;
+       uint16_t new_mctrl;
+
+       /* we can only alter DTR */
+       clear &= TIOCM_DTR;
+       set &= TIOCM_DTR;
+
+       spin_lock_irqsave(&hp->lock, flags);
+
+       new_mctrl = (hp->mctrl & ~clear) | set;
+
+       if (hp->mctrl != new_mctrl) {
+               hvsi_set_mctrl(hp, new_mctrl);
+               hp->mctrl = new_mctrl;
+       }
+       spin_unlock_irqrestore(&hp->lock, flags);
+
+       return 0;
+}
+
+
+static const struct tty_operations hvsi_ops = {
+       .open = hvsi_open,
+       .close = hvsi_close,
+       .write = hvsi_write,
+       .hangup = hvsi_hangup,
+       .write_room = hvsi_write_room,
+       .chars_in_buffer = hvsi_chars_in_buffer,
+       .throttle = hvsi_throttle,
+       .unthrottle = hvsi_unthrottle,
+       .tiocmget = hvsi_tiocmget,
+       .tiocmset = hvsi_tiocmset,
+};
+
+static int __init hvsi_init(void)
+{
+       int i;
+
+       hvsi_driver = alloc_tty_driver(hvsi_count);
+       if (!hvsi_driver)
+               return -ENOMEM;
+
+       hvsi_driver->owner = THIS_MODULE;
+       hvsi_driver->driver_name = "hvsi";
+       hvsi_driver->name = "hvsi";
+       hvsi_driver->major = HVSI_MAJOR;
+       hvsi_driver->minor_start = HVSI_MINOR;
+       hvsi_driver->type = TTY_DRIVER_TYPE_SYSTEM;
+       hvsi_driver->init_termios = tty_std_termios;
+       hvsi_driver->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL;
+       hvsi_driver->init_termios.c_ispeed = 9600;
+       hvsi_driver->init_termios.c_ospeed = 9600;
+       hvsi_driver->flags = TTY_DRIVER_REAL_RAW;
+       tty_set_operations(hvsi_driver, &hvsi_ops);
+
+       for (i=0; i < hvsi_count; i++) {
+               struct hvsi_struct *hp = &hvsi_ports[i];
+               int ret = 1;
+
+               ret = request_irq(hp->virq, hvsi_interrupt, IRQF_DISABLED, "hvsi", hp);
+               if (ret)
+                       printk(KERN_ERR "HVSI: couldn't reserve irq 0x%x (error %i)\n",
+                               hp->virq, ret);
+       }
+       hvsi_wait = wait_for_state; /* irqs active now */
+
+       if (tty_register_driver(hvsi_driver))
+               panic("Couldn't register hvsi console driver\n");
+
+       printk(KERN_DEBUG "HVSI: registered %i devices\n", hvsi_count);
+
+       return 0;
+}
+device_initcall(hvsi_init);
+
+/***** console (not tty) code: *****/
+
+static void hvsi_console_print(struct console *console, const char *buf,
+               unsigned int count)
+{
+       struct hvsi_struct *hp = &hvsi_ports[console->index];
+       char c[HVSI_MAX_OUTGOING_DATA] __ALIGNED__;
+       unsigned int i = 0, n = 0;
+       int ret, donecr = 0;
+
+       mb();
+       if (!is_open(hp))
+               return;
+
+       /*
+        * ugh, we have to translate LF -> CRLF ourselves, in place.
+        * copied from hvc_console.c:
+        */
+       while (count > 0 || i > 0) {
+               if (count > 0 && i < sizeof(c)) {
+                       if (buf[n] == '\n' && !donecr) {
+                               c[i++] = '\r';
+                               donecr = 1;
+                       } else {
+                               c[i++] = buf[n++];
+                               donecr = 0;
+                               --count;
+                       }
+               } else {
+                       ret = hvsi_put_chars(hp, c, i);
+                       if (ret < 0)
+                               i = 0;
+                       i -= ret;
+               }
+       }
+}
+
+static struct tty_driver *hvsi_console_device(struct console *console,
+       int *index)
+{
+       *index = console->index;
+       return hvsi_driver;
+}
+
+static int __init hvsi_console_setup(struct console *console, char *options)
+{
+       struct hvsi_struct *hp;
+       int ret;
+
+       if (console->index < 0 || console->index >= hvsi_count)
+               return -1;
+       hp = &hvsi_ports[console->index];
+
+       /* give the FSP a chance to change the baud rate when we re-open */
+       hvsi_close_protocol(hp);
+
+       ret = hvsi_handshake(hp);
+       if (ret < 0)
+               return ret;
+
+       ret = hvsi_get_mctrl(hp);
+       if (ret < 0)
+               return ret;
+
+       ret = hvsi_set_mctrl(hp, hp->mctrl | TIOCM_DTR);
+       if (ret < 0)
+               return ret;
+
+       hp->flags |= HVSI_CONSOLE;
+
+       return 0;
+}
+
+static struct console hvsi_console = {
+       .name           = "hvsi",
+       .write          = hvsi_console_print,
+       .device         = hvsi_console_device,
+       .setup          = hvsi_console_setup,
+       .flags          = CON_PRINTBUFFER,
+       .index          = -1,
+};
+
+static int __init hvsi_console_init(void)
+{
+       struct device_node *vty;
+
+       hvsi_wait = poll_for_state; /* no irqs yet; must poll */
+
+       /* search device tree for vty nodes */
+       for (vty = of_find_compatible_node(NULL, "serial", "hvterm-protocol");
+                       vty != NULL;
+                       vty = of_find_compatible_node(vty, "serial", "hvterm-protocol")) {
+               struct hvsi_struct *hp;
+               const uint32_t *vtermno, *irq;
+
+               vtermno = of_get_property(vty, "reg", NULL);
+               irq = of_get_property(vty, "interrupts", NULL);
+               if (!vtermno || !irq)
+                       continue;
+
+               if (hvsi_count >= MAX_NR_HVSI_CONSOLES) {
+                       of_node_put(vty);
+                       break;
+               }
+
+               hp = &hvsi_ports[hvsi_count];
+               INIT_DELAYED_WORK(&hp->writer, hvsi_write_worker);
+               INIT_WORK(&hp->handshaker, hvsi_handshaker);
+               init_waitqueue_head(&hp->emptyq);
+               init_waitqueue_head(&hp->stateq);
+               spin_lock_init(&hp->lock);
+               hp->index = hvsi_count;
+               hp->inbuf_end = hp->inbuf;
+               hp->state = HVSI_CLOSED;
+               hp->vtermno = *vtermno;
+               hp->virq = irq_create_mapping(NULL, irq[0]);
+               if (hp->virq == NO_IRQ) {
+                       printk(KERN_ERR "%s: couldn't create irq mapping for 0x%x\n",
+                               __func__, irq[0]);
+                       continue;
+               }
+
+               hvsi_count++;
+       }
+
+       if (hvsi_count)
+               register_console(&hvsi_console);
+       return 0;
+}
+console_initcall(hvsi_console_init);
diff --git a/drivers/tty/hvc/virtio_console.c b/drivers/tty/hvc/virtio_console.c
new file mode 100644 (file)
index 0000000..896a2ce
--- /dev/null
@@ -0,0 +1,1838 @@
+/*
+ * Copyright (C) 2006, 2007, 2009 Rusty Russell, IBM Corporation
+ * Copyright (C) 2009, 2010 Red Hat, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+#include <linux/cdev.h>
+#include <linux/debugfs.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/fs.h>
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/poll.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/virtio.h>
+#include <linux/virtio_console.h>
+#include <linux/wait.h>
+#include <linux/workqueue.h>
+#include "hvc_console.h"
+
+/*
+ * This is a global struct for storing common data for all the devices
+ * this driver handles.
+ *
+ * Mainly, it has a linked list for all the consoles in one place so
+ * that callbacks from hvc for get_chars(), put_chars() work properly
+ * across multiple devices and multiple ports per device.
+ */
+struct ports_driver_data {
+       /* Used for registering chardevs */
+       struct class *class;
+
+       /* Used for exporting per-port information to debugfs */
+       struct dentry *debugfs_dir;
+
+       /* List of all the devices we're handling */
+       struct list_head portdevs;
+
+       /* Number of devices this driver is handling */
+       unsigned int index;
+
+       /*
+        * This is used to keep track of the number of hvc consoles
+        * spawned by this driver.  This number is given as the first
+        * argument to hvc_alloc().  To correctly map an initial
+        * console spawned via hvc_instantiate to the console being
+        * hooked up via hvc_alloc, we need to pass the same vtermno.
+        *
+        * We also just assume the first console being initialised was
+        * the first one that got used as the initial console.
+        */
+       unsigned int next_vtermno;
+
+       /* All the console devices handled by this driver */
+       struct list_head consoles;
+};
+static struct ports_driver_data pdrvdata;
+
+DEFINE_SPINLOCK(pdrvdata_lock);
+
+/* This struct holds information that's relevant only for console ports */
+struct console {
+       /* We'll place all consoles in a list in the pdrvdata struct */
+       struct list_head list;
+
+       /* The hvc device associated with this console port */
+       struct hvc_struct *hvc;
+
+       /* The size of the console */
+       struct winsize ws;
+
+       /*
+        * This number identifies the number that we used to register
+        * with hvc in hvc_instantiate() and hvc_alloc(); this is the
+        * number passed on by the hvc callbacks to us to
+        * differentiate between the other console ports handled by
+        * this driver
+        */
+       u32 vtermno;
+};
+
+struct port_buffer {
+       char *buf;
+
+       /* size of the buffer in *buf above */
+       size_t size;
+
+       /* used length of the buffer */
+       size_t len;
+       /* offset in the buf from which to consume data */
+       size_t offset;
+};
+
+/*
+ * This is a per-device struct that stores data common to all the
+ * ports for that device (vdev->priv).
+ */
+struct ports_device {
+       /* Next portdev in the list, head is in the pdrvdata struct */
+       struct list_head list;
+
+       /*
+        * Workqueue handlers where we process deferred work after
+        * notification
+        */
+       struct work_struct control_work;
+
+       struct list_head ports;
+
+       /* To protect the list of ports */
+       spinlock_t ports_lock;
+
+       /* To protect the vq operations for the control channel */
+       spinlock_t cvq_lock;
+
+       /* The current config space is stored here */
+       struct virtio_console_config config;
+
+       /* The virtio device we're associated with */
+       struct virtio_device *vdev;
+
+       /*
+        * A couple of virtqueues for the control channel: one for
+        * guest->host transfers, one for host->guest transfers
+        */
+       struct virtqueue *c_ivq, *c_ovq;
+
+       /* Array of per-port IO virtqueues */
+       struct virtqueue **in_vqs, **out_vqs;
+
+       /* Used for numbering devices for sysfs and debugfs */
+       unsigned int drv_index;
+
+       /* Major number for this device.  Ports will be created as minors. */
+       int chr_major;
+};
+
+/* This struct holds the per-port data */
+struct port {
+       /* Next port in the list, head is in the ports_device */
+       struct list_head list;
+
+       /* Pointer to the parent virtio_console device */
+       struct ports_device *portdev;
+
+       /* The current buffer from which data has to be fed to readers */
+       struct port_buffer *inbuf;
+
+       /*
+        * To protect the operations on the in_vq associated with this
+        * port.  Has to be a spinlock because it can be called from
+        * interrupt context (get_char()).
+        */
+       spinlock_t inbuf_lock;
+
+       /* Protect the operations on the out_vq. */
+       spinlock_t outvq_lock;
+
+       /* The IO vqs for this port */
+       struct virtqueue *in_vq, *out_vq;
+
+       /* File in the debugfs directory that exposes this port's information */
+       struct dentry *debugfs_file;
+
+       /*
+        * The entries in this struct will be valid if this port is
+        * hooked up to an hvc console
+        */
+       struct console cons;
+
+       /* Each port associates with a separate char device */
+       struct cdev *cdev;
+       struct device *dev;
+
+       /* Reference-counting to handle port hot-unplugs and file operations */
+       struct kref kref;
+
+       /* A waitqueue for poll() or blocking read operations */
+       wait_queue_head_t waitqueue;
+
+       /* The 'name' of the port that we expose via sysfs properties */
+       char *name;
+
+       /* We can notify apps of host connect / disconnect events via SIGIO */
+       struct fasync_struct *async_queue;
+
+       /* The 'id' to identify the port with the Host */
+       u32 id;
+
+       bool outvq_full;
+
+       /* Is the host device open */
+       bool host_connected;
+
+       /* We should allow only one process to open a port */
+       bool guest_connected;
+};
+
+/* This is the very early arch-specified put chars function. */
+static int (*early_put_chars)(u32, const char *, int);
+
+static struct port *find_port_by_vtermno(u32 vtermno)
+{
+       struct port *port;
+       struct console *cons;
+       unsigned long flags;
+
+       spin_lock_irqsave(&pdrvdata_lock, flags);
+       list_for_each_entry(cons, &pdrvdata.consoles, list) {
+               if (cons->vtermno == vtermno) {
+                       port = container_of(cons, struct port, cons);
+                       goto out;
+               }
+       }
+       port = NULL;
+out:
+       spin_unlock_irqrestore(&pdrvdata_lock, flags);
+       return port;
+}
+
+static struct port *find_port_by_devt_in_portdev(struct ports_device *portdev,
+                                                dev_t dev)
+{
+       struct port *port;
+       unsigned long flags;
+
+       spin_lock_irqsave(&portdev->ports_lock, flags);
+       list_for_each_entry(port, &portdev->ports, list)
+               if (port->cdev->dev == dev)
+                       goto out;
+       port = NULL;
+out:
+       spin_unlock_irqrestore(&portdev->ports_lock, flags);
+
+       return port;
+}
+
+static struct port *find_port_by_devt(dev_t dev)
+{
+       struct ports_device *portdev;
+       struct port *port;
+       unsigned long flags;
+
+       spin_lock_irqsave(&pdrvdata_lock, flags);
+       list_for_each_entry(portdev, &pdrvdata.portdevs, list) {
+               port = find_port_by_devt_in_portdev(portdev, dev);
+               if (port)
+                       goto out;
+       }
+       port = NULL;
+out:
+       spin_unlock_irqrestore(&pdrvdata_lock, flags);
+       return port;
+}
+
+static struct port *find_port_by_id(struct ports_device *portdev, u32 id)
+{
+       struct port *port;
+       unsigned long flags;
+
+       spin_lock_irqsave(&portdev->ports_lock, flags);
+       list_for_each_entry(port, &portdev->ports, list)
+               if (port->id == id)
+                       goto out;
+       port = NULL;
+out:
+       spin_unlock_irqrestore(&portdev->ports_lock, flags);
+
+       return port;
+}
+
+static struct port *find_port_by_vq(struct ports_device *portdev,
+                                   struct virtqueue *vq)
+{
+       struct port *port;
+       unsigned long flags;
+
+       spin_lock_irqsave(&portdev->ports_lock, flags);
+       list_for_each_entry(port, &portdev->ports, list)
+               if (port->in_vq == vq || port->out_vq == vq)
+                       goto out;
+       port = NULL;
+out:
+       spin_unlock_irqrestore(&portdev->ports_lock, flags);
+       return port;
+}
+
+static bool is_console_port(struct port *port)
+{
+       if (port->cons.hvc)
+               return true;
+       return false;
+}
+
+static inline bool use_multiport(struct ports_device *portdev)
+{
+       /*
+        * This condition can be true when put_chars is called from
+        * early_init
+        */
+       if (!portdev->vdev)
+               return 0;
+       return portdev->vdev->features[0] & (1 << VIRTIO_CONSOLE_F_MULTIPORT);
+}
+
+static void free_buf(struct port_buffer *buf)
+{
+       kfree(buf->buf);
+       kfree(buf);
+}
+
+static struct port_buffer *alloc_buf(size_t buf_size)
+{
+       struct port_buffer *buf;
+
+       buf = kmalloc(sizeof(*buf), GFP_KERNEL);
+       if (!buf)
+               goto fail;
+       buf->buf = kzalloc(buf_size, GFP_KERNEL);
+       if (!buf->buf)
+               goto free_buf;
+       buf->len = 0;
+       buf->offset = 0;
+       buf->size = buf_size;
+       return buf;
+
+free_buf:
+       kfree(buf);
+fail:
+       return NULL;
+}
+
+/* Callers should take appropriate locks */
+static void *get_inbuf(struct port *port)
+{
+       struct port_buffer *buf;
+       struct virtqueue *vq;
+       unsigned int len;
+
+       vq = port->in_vq;
+       buf = virtqueue_get_buf(vq, &len);
+       if (buf) {
+               buf->len = len;
+               buf->offset = 0;
+       }
+       return buf;
+}
+
+/*
+ * Create a scatter-gather list representing our input buffer and put
+ * it in the queue.
+ *
+ * Callers should take appropriate locks.
+ */
+static int add_inbuf(struct virtqueue *vq, struct port_buffer *buf)
+{
+       struct scatterlist sg[1];
+       int ret;
+
+       sg_init_one(sg, buf->buf, buf->size);
+
+       ret = virtqueue_add_buf(vq, sg, 0, 1, buf);
+       virtqueue_kick(vq);
+       return ret;
+}
+
+/* Discard any unread data this port has. Callers lockers. */
+static void discard_port_data(struct port *port)
+{
+       struct port_buffer *buf;
+       struct virtqueue *vq;
+       unsigned int len;
+       int ret;
+
+       vq = port->in_vq;
+       if (port->inbuf)
+               buf = port->inbuf;
+       else
+               buf = virtqueue_get_buf(vq, &len);
+
+       ret = 0;
+       while (buf) {
+               if (add_inbuf(vq, buf) < 0) {
+                       ret++;
+                       free_buf(buf);
+               }
+               buf = virtqueue_get_buf(vq, &len);
+       }
+       port->inbuf = NULL;
+       if (ret)
+               dev_warn(port->dev, "Errors adding %d buffers back to vq\n",
+                        ret);
+}
+
+static bool port_has_data(struct port *port)
+{
+       unsigned long flags;
+       bool ret;
+
+       spin_lock_irqsave(&port->inbuf_lock, flags);
+       if (port->inbuf) {
+               ret = true;
+               goto out;
+       }
+       port->inbuf = get_inbuf(port);
+       if (port->inbuf) {
+               ret = true;
+               goto out;
+       }
+       ret = false;
+out:
+       spin_unlock_irqrestore(&port->inbuf_lock, flags);
+       return ret;
+}
+
+static ssize_t __send_control_msg(struct ports_device *portdev, u32 port_id,
+                                 unsigned int event, unsigned int value)
+{
+       struct scatterlist sg[1];
+       struct virtio_console_control cpkt;
+       struct virtqueue *vq;
+       unsigned int len;
+
+       if (!use_multiport(portdev))
+               return 0;
+
+       cpkt.id = port_id;
+       cpkt.event = event;
+       cpkt.value = value;
+
+       vq = portdev->c_ovq;
+
+       sg_init_one(sg, &cpkt, sizeof(cpkt));
+       if (virtqueue_add_buf(vq, sg, 1, 0, &cpkt) >= 0) {
+               virtqueue_kick(vq);
+               while (!virtqueue_get_buf(vq, &len))
+                       cpu_relax();
+       }
+       return 0;
+}
+
+static ssize_t send_control_msg(struct port *port, unsigned int event,
+                               unsigned int value)
+{
+       /* Did the port get unplugged before userspace closed it? */
+       if (port->portdev)
+               return __send_control_msg(port->portdev, port->id, event, value);
+       return 0;
+}
+
+/* Callers must take the port->outvq_lock */
+static void reclaim_consumed_buffers(struct port *port)
+{
+       void *buf;
+       unsigned int len;
+
+       while ((buf = virtqueue_get_buf(port->out_vq, &len))) {
+               kfree(buf);
+               port->outvq_full = false;
+       }
+}
+
+static ssize_t send_buf(struct port *port, void *in_buf, size_t in_count,
+                       bool nonblock)
+{
+       struct scatterlist sg[1];
+       struct virtqueue *out_vq;
+       ssize_t ret;
+       unsigned long flags;
+       unsigned int len;
+
+       out_vq = port->out_vq;
+
+       spin_lock_irqsave(&port->outvq_lock, flags);
+
+       reclaim_consumed_buffers(port);
+
+       sg_init_one(sg, in_buf, in_count);
+       ret = virtqueue_add_buf(out_vq, sg, 1, 0, in_buf);
+
+       /* Tell Host to go! */
+       virtqueue_kick(out_vq);
+
+       if (ret < 0) {
+               in_count = 0;
+               goto done;
+       }
+
+       if (ret == 0)
+               port->outvq_full = true;
+
+       if (nonblock)
+               goto done;
+
+       /*
+        * Wait till the host acknowledges it pushed out the data we
+        * sent.  This is done for data from the hvc_console; the tty
+        * operations are performed with spinlocks held so we can't
+        * sleep here.  An alternative would be to copy the data to a
+        * buffer and relax the spinning requirement.  The downside is
+        * we need to kmalloc a GFP_ATOMIC buffer each time the
+        * console driver writes something out.
+        */
+       while (!virtqueue_get_buf(out_vq, &len))
+               cpu_relax();
+done:
+       spin_unlock_irqrestore(&port->outvq_lock, flags);
+       /*
+        * We're expected to return the amount of data we wrote -- all
+        * of it
+        */
+       return in_count;
+}
+
+/*
+ * Give out the data that's requested from the buffer that we have
+ * queued up.
+ */
+static ssize_t fill_readbuf(struct port *port, char *out_buf, size_t out_count,
+                           bool to_user)
+{
+       struct port_buffer *buf;
+       unsigned long flags;
+
+       if (!out_count || !port_has_data(port))
+               return 0;
+
+       buf = port->inbuf;
+       out_count = min(out_count, buf->len - buf->offset);
+
+       if (to_user) {
+               ssize_t ret;
+
+               ret = copy_to_user(out_buf, buf->buf + buf->offset, out_count);
+               if (ret)
+                       return -EFAULT;
+       } else {
+               memcpy(out_buf, buf->buf + buf->offset, out_count);
+       }
+
+       buf->offset += out_count;
+
+       if (buf->offset == buf->len) {
+               /*
+                * We're done using all the data in this buffer.
+                * Re-queue so that the Host can send us more data.
+                */
+               spin_lock_irqsave(&port->inbuf_lock, flags);
+               port->inbuf = NULL;
+
+               if (add_inbuf(port->in_vq, buf) < 0)
+                       dev_warn(port->dev, "failed add_buf\n");
+
+               spin_unlock_irqrestore(&port->inbuf_lock, flags);
+       }
+       /* Return the number of bytes actually copied */
+       return out_count;
+}
+
+/* The condition that must be true for polling to end */
+static bool will_read_block(struct port *port)
+{
+       if (!port->guest_connected) {
+               /* Port got hot-unplugged. Let's exit. */
+               return false;
+       }
+       return !port_has_data(port) && port->host_connected;
+}
+
+static bool will_write_block(struct port *port)
+{
+       bool ret;
+
+       if (!port->guest_connected) {
+               /* Port got hot-unplugged. Let's exit. */
+               return false;
+       }
+       if (!port->host_connected)
+               return true;
+
+       spin_lock_irq(&port->outvq_lock);
+       /*
+        * Check if the Host has consumed any buffers since we last
+        * sent data (this is only applicable for nonblocking ports).
+        */
+       reclaim_consumed_buffers(port);
+       ret = port->outvq_full;
+       spin_unlock_irq(&port->outvq_lock);
+
+       return ret;
+}
+
+static ssize_t port_fops_read(struct file *filp, char __user *ubuf,
+                             size_t count, loff_t *offp)
+{
+       struct port *port;
+       ssize_t ret;
+
+       port = filp->private_data;
+
+       if (!port_has_data(port)) {
+               /*
+                * If nothing's connected on the host just return 0 in
+                * case of list_empty; this tells the userspace app
+                * that there's no connection
+                */
+               if (!port->host_connected)
+                       return 0;
+               if (filp->f_flags & O_NONBLOCK)
+                       return -EAGAIN;
+
+               ret = wait_event_interruptible(port->waitqueue,
+                                              !will_read_block(port));
+               if (ret < 0)
+                       return ret;
+       }
+       /* Port got hot-unplugged. */
+       if (!port->guest_connected)
+               return -ENODEV;
+       /*
+        * We could've received a disconnection message while we were
+        * waiting for more data.
+        *
+        * This check is not clubbed in the if() statement above as we
+        * might receive some data as well as the host could get
+        * disconnected after we got woken up from our wait.  So we
+        * really want to give off whatever data we have and only then
+        * check for host_connected.
+        */
+       if (!port_has_data(port) && !port->host_connected)
+               return 0;
+
+       return fill_readbuf(port, ubuf, count, true);
+}
+
+static ssize_t port_fops_write(struct file *filp, const char __user *ubuf,
+                              size_t count, loff_t *offp)
+{
+       struct port *port;
+       char *buf;
+       ssize_t ret;
+       bool nonblock;
+
+       /* Userspace could be out to fool us */
+       if (!count)
+               return 0;
+
+       port = filp->private_data;
+
+       nonblock = filp->f_flags & O_NONBLOCK;
+
+       if (will_write_block(port)) {
+               if (nonblock)
+                       return -EAGAIN;
+
+               ret = wait_event_interruptible(port->waitqueue,
+                                              !will_write_block(port));
+               if (ret < 0)
+                       return ret;
+       }
+       /* Port got hot-unplugged. */
+       if (!port->guest_connected)
+               return -ENODEV;
+
+       count = min((size_t)(32 * 1024), count);
+
+       buf = kmalloc(count, GFP_KERNEL);
+       if (!buf)
+               return -ENOMEM;
+
+       ret = copy_from_user(buf, ubuf, count);
+       if (ret) {
+               ret = -EFAULT;
+               goto free_buf;
+       }
+
+       /*
+        * We now ask send_buf() to not spin for generic ports -- we
+        * can re-use the same code path that non-blocking file
+        * descriptors take for blocking file descriptors since the
+        * wait is already done and we're certain the write will go
+        * through to the host.
+        */
+       nonblock = true;
+       ret = send_buf(port, buf, count, nonblock);
+
+       if (nonblock && ret > 0)
+               goto out;
+
+free_buf:
+       kfree(buf);
+out:
+       return ret;
+}
+
+static unsigned int port_fops_poll(struct file *filp, poll_table *wait)
+{
+       struct port *port;
+       unsigned int ret;
+
+       port = filp->private_data;
+       poll_wait(filp, &port->waitqueue, wait);
+
+       if (!port->guest_connected) {
+               /* Port got unplugged */
+               return POLLHUP;
+       }
+       ret = 0;
+       if (!will_read_block(port))
+               ret |= POLLIN | POLLRDNORM;
+       if (!will_write_block(port))
+               ret |= POLLOUT;
+       if (!port->host_connected)
+               ret |= POLLHUP;
+
+       return ret;
+}
+
+static void remove_port(struct kref *kref);
+
+static int port_fops_release(struct inode *inode, struct file *filp)
+{
+       struct port *port;
+
+       port = filp->private_data;
+
+       /* Notify host of port being closed */
+       send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 0);
+
+       spin_lock_irq(&port->inbuf_lock);
+       port->guest_connected = false;
+
+       discard_port_data(port);
+
+       spin_unlock_irq(&port->inbuf_lock);
+
+       spin_lock_irq(&port->outvq_lock);
+       reclaim_consumed_buffers(port);
+       spin_unlock_irq(&port->outvq_lock);
+
+       /*
+        * Locks aren't necessary here as a port can't be opened after
+        * unplug, and if a port isn't unplugged, a kref would already
+        * exist for the port.  Plus, taking ports_lock here would
+        * create a dependency on other locks taken by functions
+        * inside remove_port if we're the last holder of the port,
+        * creating many problems.
+        */
+       kref_put(&port->kref, remove_port);
+
+       return 0;
+}
+
+static int port_fops_open(struct inode *inode, struct file *filp)
+{
+       struct cdev *cdev = inode->i_cdev;
+       struct port *port;
+       int ret;
+
+       port = find_port_by_devt(cdev->dev);
+       filp->private_data = port;
+
+       /* Prevent against a port getting hot-unplugged at the same time */
+       spin_lock_irq(&port->portdev->ports_lock);
+       kref_get(&port->kref);
+       spin_unlock_irq(&port->portdev->ports_lock);
+
+       /*
+        * Don't allow opening of console port devices -- that's done
+        * via /dev/hvc
+        */
+       if (is_console_port(port)) {
+               ret = -ENXIO;
+               goto out;
+       }
+
+       /* Allow only one process to open a particular port at a time */
+       spin_lock_irq(&port->inbuf_lock);
+       if (port->guest_connected) {
+               spin_unlock_irq(&port->inbuf_lock);
+               ret = -EMFILE;
+               goto out;
+       }
+
+       port->guest_connected = true;
+       spin_unlock_irq(&port->inbuf_lock);
+
+       spin_lock_irq(&port->outvq_lock);
+       /*
+        * There might be a chance that we missed reclaiming a few
+        * buffers in the window of the port getting previously closed
+        * and opening now.
+        */
+       reclaim_consumed_buffers(port);
+       spin_unlock_irq(&port->outvq_lock);
+
+       nonseekable_open(inode, filp);
+
+       /* Notify host of port being opened */
+       send_control_msg(filp->private_data, VIRTIO_CONSOLE_PORT_OPEN, 1);
+
+       return 0;
+out:
+       kref_put(&port->kref, remove_port);
+       return ret;
+}
+
+static int port_fops_fasync(int fd, struct file *filp, int mode)
+{
+       struct port *port;
+
+       port = filp->private_data;
+       return fasync_helper(fd, filp, mode, &port->async_queue);
+}
+
+/*
+ * The file operations that we support: programs in the guest can open
+ * a console device, read from it, write to it, poll for data and
+ * close it.  The devices are at
+ *   /dev/vport<device number>p<port number>
+ */
+static const struct file_operations port_fops = {
+       .owner = THIS_MODULE,
+       .open  = port_fops_open,
+       .read  = port_fops_read,
+       .write = port_fops_write,
+       .poll  = port_fops_poll,
+       .release = port_fops_release,
+       .fasync = port_fops_fasync,
+       .llseek = no_llseek,
+};
+
+/*
+ * The put_chars() callback is pretty straightforward.
+ *
+ * We turn the characters into a scatter-gather list, add it to the
+ * output queue and then kick the Host.  Then we sit here waiting for
+ * it to finish: inefficient in theory, but in practice
+ * implementations will do it immediately (lguest's Launcher does).
+ */
+static int put_chars(u32 vtermno, const char *buf, int count)
+{
+       struct port *port;
+
+       if (unlikely(early_put_chars))
+               return early_put_chars(vtermno, buf, count);
+
+       port = find_port_by_vtermno(vtermno);
+       if (!port)
+               return -EPIPE;
+
+       return send_buf(port, (void *)buf, count, false);
+}
+
+/*
+ * get_chars() is the callback from the hvc_console infrastructure
+ * when an interrupt is received.
+ *
+ * We call out to fill_readbuf that gets us the required data from the
+ * buffers that are queued up.
+ */
+static int get_chars(u32 vtermno, char *buf, int count)
+{
+       struct port *port;
+
+       /* If we've not set up the port yet, we have no input to give. */
+       if (unlikely(early_put_chars))
+               return 0;
+
+       port = find_port_by_vtermno(vtermno);
+       if (!port)
+               return -EPIPE;
+
+       /* If we don't have an input queue yet, we can't get input. */
+       BUG_ON(!port->in_vq);
+
+       return fill_readbuf(port, buf, count, false);
+}
+
+static void resize_console(struct port *port)
+{
+       struct virtio_device *vdev;
+
+       /* The port could have been hot-unplugged */
+       if (!port || !is_console_port(port))
+               return;
+
+       vdev = port->portdev->vdev;
+       if (virtio_has_feature(vdev, VIRTIO_CONSOLE_F_SIZE))
+               hvc_resize(port->cons.hvc, port->cons.ws);
+}
+
+/* We set the configuration at this point, since we now have a tty */
+static int notifier_add_vio(struct hvc_struct *hp, int data)
+{
+       struct port *port;
+
+       port = find_port_by_vtermno(hp->vtermno);
+       if (!port)
+               return -EINVAL;
+
+       hp->irq_requested = 1;
+       resize_console(port);
+
+       return 0;
+}
+
+static void notifier_del_vio(struct hvc_struct *hp, int data)
+{
+       hp->irq_requested = 0;
+}
+
+/* The operations for console ports. */
+static const struct hv_ops hv_ops = {
+       .get_chars = get_chars,
+       .put_chars = put_chars,
+       .notifier_add = notifier_add_vio,
+       .notifier_del = notifier_del_vio,
+       .notifier_hangup = notifier_del_vio,
+};
+
+/*
+ * Console drivers are initialized very early so boot messages can go
+ * out, so we do things slightly differently from the generic virtio
+ * initialization of the net and block drivers.
+ *
+ * At this stage, the console is output-only.  It's too early to set
+ * up a virtqueue, so we let the drivers do some boutique early-output
+ * thing.
+ */
+int __init virtio_cons_early_init(int (*put_chars)(u32, const char *, int))
+{
+       early_put_chars = put_chars;
+       return hvc_instantiate(0, 0, &hv_ops);
+}
+
+int init_port_console(struct port *port)
+{
+       int ret;
+
+       /*
+        * The Host's telling us this port is a console port.  Hook it
+        * up with an hvc console.
+        *
+        * To set up and manage our virtual console, we call
+        * hvc_alloc().
+        *
+        * The first argument of hvc_alloc() is the virtual console
+        * number.  The second argument is the parameter for the
+        * notification mechanism (like irq number).  We currently
+        * leave this as zero, virtqueues have implicit notifications.
+        *
+        * The third argument is a "struct hv_ops" containing the
+        * put_chars() get_chars(), notifier_add() and notifier_del()
+        * pointers.  The final argument is the output buffer size: we
+        * can do any size, so we put PAGE_SIZE here.
+        */
+       port->cons.vtermno = pdrvdata.next_vtermno;
+
+       port->cons.hvc = hvc_alloc(port->cons.vtermno, 0, &hv_ops, PAGE_SIZE);
+       if (IS_ERR(port->cons.hvc)) {
+               ret = PTR_ERR(port->cons.hvc);
+               dev_err(port->dev,
+                       "error %d allocating hvc for port\n", ret);
+               port->cons.hvc = NULL;
+               return ret;
+       }
+       spin_lock_irq(&pdrvdata_lock);
+       pdrvdata.next_vtermno++;
+       list_add_tail(&port->cons.list, &pdrvdata.consoles);
+       spin_unlock_irq(&pdrvdata_lock);
+       port->guest_connected = true;
+
+       /*
+        * Start using the new console output if this is the first
+        * console to come up.
+        */
+       if (early_put_chars)
+               early_put_chars = NULL;
+
+       /* Notify host of port being opened */
+       send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 1);
+
+       return 0;
+}
+
+static ssize_t show_port_name(struct device *dev,
+                             struct device_attribute *attr, char *buffer)
+{
+       struct port *port;
+
+       port = dev_get_drvdata(dev);
+
+       return sprintf(buffer, "%s\n", port->name);
+}
+
+static DEVICE_ATTR(name, S_IRUGO, show_port_name, NULL);
+
+static struct attribute *port_sysfs_entries[] = {
+       &dev_attr_name.attr,
+       NULL
+};
+
+static struct attribute_group port_attribute_group = {
+       .name = NULL,           /* put in device directory */
+       .attrs = port_sysfs_entries,
+};
+
+static int debugfs_open(struct inode *inode, struct file *filp)
+{
+       filp->private_data = inode->i_private;
+       return 0;
+}
+
+static ssize_t debugfs_read(struct file *filp, char __user *ubuf,
+                           size_t count, loff_t *offp)
+{
+       struct port *port;
+       char *buf;
+       ssize_t ret, out_offset, out_count;
+
+       out_count = 1024;
+       buf = kmalloc(out_count, GFP_KERNEL);
+       if (!buf)
+               return -ENOMEM;
+
+       port = filp->private_data;
+       out_offset = 0;
+       out_offset += snprintf(buf + out_offset, out_count,
+                              "name: %s\n", port->name ? port->name : "");
+       out_offset += snprintf(buf + out_offset, out_count - out_offset,
+                              "guest_connected: %d\n", port->guest_connected);
+       out_offset += snprintf(buf + out_offset, out_count - out_offset,
+                              "host_connected: %d\n", port->host_connected);
+       out_offset += snprintf(buf + out_offset, out_count - out_offset,
+                              "outvq_full: %d\n", port->outvq_full);
+       out_offset += snprintf(buf + out_offset, out_count - out_offset,
+                              "is_console: %s\n",
+                              is_console_port(port) ? "yes" : "no");
+       out_offset += snprintf(buf + out_offset, out_count - out_offset,
+                              "console_vtermno: %u\n", port->cons.vtermno);
+
+       ret = simple_read_from_buffer(ubuf, count, offp, buf, out_offset);
+       kfree(buf);
+       return ret;
+}
+
+static const struct file_operations port_debugfs_ops = {
+       .owner = THIS_MODULE,
+       .open  = debugfs_open,
+       .read  = debugfs_read,
+};
+
+static void set_console_size(struct port *port, u16 rows, u16 cols)
+{
+       if (!port || !is_console_port(port))
+               return;
+
+       port->cons.ws.ws_row = rows;
+       port->cons.ws.ws_col = cols;
+}
+
+static unsigned int fill_queue(struct virtqueue *vq, spinlock_t *lock)
+{
+       struct port_buffer *buf;
+       unsigned int nr_added_bufs;
+       int ret;
+
+       nr_added_bufs = 0;
+       do {
+               buf = alloc_buf(PAGE_SIZE);
+               if (!buf)
+                       break;
+
+               spin_lock_irq(lock);
+               ret = add_inbuf(vq, buf);
+               if (ret < 0) {
+                       spin_unlock_irq(lock);
+                       free_buf(buf);
+                       break;
+               }
+               nr_added_bufs++;
+               spin_unlock_irq(lock);
+       } while (ret > 0);
+
+       return nr_added_bufs;
+}
+
+static void send_sigio_to_port(struct port *port)
+{
+       if (port->async_queue && port->guest_connected)
+               kill_fasync(&port->async_queue, SIGIO, POLL_OUT);
+}
+
+static int add_port(struct ports_device *portdev, u32 id)
+{
+       char debugfs_name[16];
+       struct port *port;
+       struct port_buffer *buf;
+       dev_t devt;
+       unsigned int nr_added_bufs;
+       int err;
+
+       port = kmalloc(sizeof(*port), GFP_KERNEL);
+       if (!port) {
+               err = -ENOMEM;
+               goto fail;
+       }
+       kref_init(&port->kref);
+
+       port->portdev = portdev;
+       port->id = id;
+
+       port->name = NULL;
+       port->inbuf = NULL;
+       port->cons.hvc = NULL;
+       port->async_queue = NULL;
+
+       port->cons.ws.ws_row = port->cons.ws.ws_col = 0;
+
+       port->host_connected = port->guest_connected = false;
+
+       port->outvq_full = false;
+
+       port->in_vq = portdev->in_vqs[port->id];
+       port->out_vq = portdev->out_vqs[port->id];
+
+       port->cdev = cdev_alloc();
+       if (!port->cdev) {
+               dev_err(&port->portdev->vdev->dev, "Error allocating cdev\n");
+               err = -ENOMEM;
+               goto free_port;
+       }
+       port->cdev->ops = &port_fops;
+
+       devt = MKDEV(portdev->chr_major, id);
+       err = cdev_add(port->cdev, devt, 1);
+       if (err < 0) {
+               dev_err(&port->portdev->vdev->dev,
+                       "Error %d adding cdev for port %u\n", err, id);
+               goto free_cdev;
+       }
+       port->dev = device_create(pdrvdata.class, &port->portdev->vdev->dev,
+                                 devt, port, "vport%up%u",
+                                 port->portdev->drv_index, id);
+       if (IS_ERR(port->dev)) {
+               err = PTR_ERR(port->dev);
+               dev_err(&port->portdev->vdev->dev,
+                       "Error %d creating device for port %u\n",
+                       err, id);
+               goto free_cdev;
+       }
+
+       spin_lock_init(&port->inbuf_lock);
+       spin_lock_init(&port->outvq_lock);
+       init_waitqueue_head(&port->waitqueue);
+
+       /* Fill the in_vq with buffers so the host can send us data. */
+       nr_added_bufs = fill_queue(port->in_vq, &port->inbuf_lock);
+       if (!nr_added_bufs) {
+               dev_err(port->dev, "Error allocating inbufs\n");
+               err = -ENOMEM;
+               goto free_device;
+       }
+
+       /*
+        * If we're not using multiport support, this has to be a console port
+        */
+       if (!use_multiport(port->portdev)) {
+               err = init_port_console(port);
+               if (err)
+                       goto free_inbufs;
+       }
+
+       spin_lock_irq(&portdev->ports_lock);
+       list_add_tail(&port->list, &port->portdev->ports);
+       spin_unlock_irq(&portdev->ports_lock);
+
+       /*
+        * Tell the Host we're set so that it can send us various
+        * configuration parameters for this port (eg, port name,
+        * caching, whether this is a console port, etc.)
+        */
+       send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1);
+
+       if (pdrvdata.debugfs_dir) {
+               /*
+                * Finally, create the debugfs file that we can use to
+                * inspect a port's state at any time
+                */
+               sprintf(debugfs_name, "vport%up%u",
+                       port->portdev->drv_index, id);
+               port->debugfs_file = debugfs_create_file(debugfs_name, 0444,
+                                                        pdrvdata.debugfs_dir,
+                                                        port,
+                                                        &port_debugfs_ops);
+       }
+       return 0;
+
+free_inbufs:
+       while ((buf = virtqueue_detach_unused_buf(port->in_vq)))
+               free_buf(buf);
+free_device:
+       device_destroy(pdrvdata.class, port->dev->devt);
+free_cdev:
+       cdev_del(port->cdev);
+free_port:
+       kfree(port);
+fail:
+       /* The host might want to notify management sw about port add failure */
+       __send_control_msg(portdev, id, VIRTIO_CONSOLE_PORT_READY, 0);
+       return err;
+}
+
+/* No users remain, remove all port-specific data. */
+static void remove_port(struct kref *kref)
+{
+       struct port *port;
+
+       port = container_of(kref, struct port, kref);
+
+       sysfs_remove_group(&port->dev->kobj, &port_attribute_group);
+       device_destroy(pdrvdata.class, port->dev->devt);
+       cdev_del(port->cdev);
+
+       kfree(port->name);
+
+       debugfs_remove(port->debugfs_file);
+
+       kfree(port);
+}
+
+/*
+ * Port got unplugged.  Remove port from portdev's list and drop the
+ * kref reference.  If no userspace has this port opened, it will
+ * result in immediate removal the port.
+ */
+static void unplug_port(struct port *port)
+{
+       struct port_buffer *buf;
+
+       spin_lock_irq(&port->portdev->ports_lock);
+       list_del(&port->list);
+       spin_unlock_irq(&port->portdev->ports_lock);
+
+       if (port->guest_connected) {
+               port->guest_connected = false;
+               port->host_connected = false;
+               wake_up_interruptible(&port->waitqueue);
+
+               /* Let the app know the port is going down. */
+               send_sigio_to_port(port);
+       }
+
+       if (is_console_port(port)) {
+               spin_lock_irq(&pdrvdata_lock);
+               list_del(&port->cons.list);
+               spin_unlock_irq(&pdrvdata_lock);
+#if 0
+               /*
+                * hvc_remove() not called as removing one hvc port
+                * results in other hvc ports getting frozen.
+                *
+                * Once this is resolved in hvc, this functionality
+                * will be enabled.  Till that is done, the -EPIPE
+                * return from get_chars() above will help
+                * hvc_console.c to clean up on ports we remove here.
+                */
+               hvc_remove(port->cons.hvc);
+#endif
+       }
+
+       /* Remove unused data this port might have received. */
+       discard_port_data(port);
+
+       reclaim_consumed_buffers(port);
+
+       /* Remove buffers we queued up for the Host to send us data in. */
+       while ((buf = virtqueue_detach_unused_buf(port->in_vq)))
+               free_buf(buf);
+
+       /*
+        * We should just assume the device itself has gone off --
+        * else a close on an open port later will try to send out a
+        * control message.
+        */
+       port->portdev = NULL;
+
+       /*
+        * Locks around here are not necessary - a port can't be
+        * opened after we removed the port struct from ports_list
+        * above.
+        */
+       kref_put(&port->kref, remove_port);
+}
+
+/* Any private messages that the Host and Guest want to share */
+static void handle_control_message(struct ports_device *portdev,
+                                  struct port_buffer *buf)
+{
+       struct virtio_console_control *cpkt;
+       struct port *port;
+       size_t name_size;
+       int err;
+
+       cpkt = (struct virtio_console_control *)(buf->buf + buf->offset);
+
+       port = find_port_by_id(portdev, cpkt->id);
+       if (!port && cpkt->event != VIRTIO_CONSOLE_PORT_ADD) {
+               /* No valid header at start of buffer.  Drop it. */
+               dev_dbg(&portdev->vdev->dev,
+                       "Invalid index %u in control packet\n", cpkt->id);
+               return;
+       }
+
+       switch (cpkt->event) {
+       case VIRTIO_CONSOLE_PORT_ADD:
+               if (port) {
+                       dev_dbg(&portdev->vdev->dev,
+                               "Port %u already added\n", port->id);
+                       send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1);
+                       break;
+               }
+               if (cpkt->id >= portdev->config.max_nr_ports) {
+                       dev_warn(&portdev->vdev->dev,
+                               "Request for adding port with out-of-bound id %u, max. supported id: %u\n",
+                               cpkt->id, portdev->config.max_nr_ports - 1);
+                       break;
+               }
+               add_port(portdev, cpkt->id);
+               break;
+       case VIRTIO_CONSOLE_PORT_REMOVE:
+               unplug_port(port);
+               break;
+       case VIRTIO_CONSOLE_CONSOLE_PORT:
+               if (!cpkt->value)
+                       break;
+               if (is_console_port(port))
+                       break;
+
+               init_port_console(port);
+               /*
+                * Could remove the port here in case init fails - but
+                * have to notify the host first.
+                */
+               break;
+       case VIRTIO_CONSOLE_RESIZE: {
+               struct {
+                       __u16 rows;
+                       __u16 cols;
+               } size;
+
+               if (!is_console_port(port))
+                       break;
+
+               memcpy(&size, buf->buf + buf->offset + sizeof(*cpkt),
+                      sizeof(size));
+               set_console_size(port, size.rows, size.cols);
+
+               port->cons.hvc->irq_requested = 1;
+               resize_console(port);
+               break;
+       }
+       case VIRTIO_CONSOLE_PORT_OPEN:
+               port->host_connected = cpkt->value;
+               wake_up_interruptible(&port->waitqueue);
+               /*
+                * If the host port got closed and the host had any
+                * unconsumed buffers, we'll be able to reclaim them
+                * now.
+                */
+               spin_lock_irq(&port->outvq_lock);
+               reclaim_consumed_buffers(port);
+               spin_unlock_irq(&port->outvq_lock);
+
+               /*
+                * If the guest is connected, it'll be interested in
+                * knowing the host connection state changed.
+                */
+               send_sigio_to_port(port);
+               break;
+       case VIRTIO_CONSOLE_PORT_NAME:
+               /*
+                * Skip the size of the header and the cpkt to get the size
+                * of the name that was sent
+                */
+               name_size = buf->len - buf->offset - sizeof(*cpkt) + 1;
+
+               port->name = kmalloc(name_size, GFP_KERNEL);
+               if (!port->name) {
+                       dev_err(port->dev,
+                               "Not enough space to store port name\n");
+                       break;
+               }
+               strncpy(port->name, buf->buf + buf->offset + sizeof(*cpkt),
+                       name_size - 1);
+               port->name[name_size - 1] = 0;
+
+               /*
+                * Since we only have one sysfs attribute, 'name',
+                * create it only if we have a name for the port.
+                */
+               err = sysfs_create_group(&port->dev->kobj,
+                                        &port_attribute_group);
+               if (err) {
+                       dev_err(port->dev,
+                               "Error %d creating sysfs device attributes\n",
+                               err);
+               } else {
+                       /*
+                        * Generate a udev event so that appropriate
+                        * symlinks can be created based on udev
+                        * rules.
+                        */
+                       kobject_uevent(&port->dev->kobj, KOBJ_CHANGE);
+               }
+               break;
+       }
+}
+
+static void control_work_handler(struct work_struct *work)
+{
+       struct ports_device *portdev;
+       struct virtqueue *vq;
+       struct port_buffer *buf;
+       unsigned int len;
+
+       portdev = container_of(work, struct ports_device, control_work);
+       vq = portdev->c_ivq;
+
+       spin_lock(&portdev->cvq_lock);
+       while ((buf = virtqueue_get_buf(vq, &len))) {
+               spin_unlock(&portdev->cvq_lock);
+
+               buf->len = len;
+               buf->offset = 0;
+
+               handle_control_message(portdev, buf);
+
+               spin_lock(&portdev->cvq_lock);
+               if (add_inbuf(portdev->c_ivq, buf) < 0) {
+                       dev_warn(&portdev->vdev->dev,
+                                "Error adding buffer to queue\n");
+                       free_buf(buf);
+               }
+       }
+       spin_unlock(&portdev->cvq_lock);
+}
+
+static void in_intr(struct virtqueue *vq)
+{
+       struct port *port;
+       unsigned long flags;
+
+       port = find_port_by_vq(vq->vdev->priv, vq);
+       if (!port)
+               return;
+
+       spin_lock_irqsave(&port->inbuf_lock, flags);
+       if (!port->inbuf)
+               port->inbuf = get_inbuf(port);
+
+       /*
+        * Don't queue up data when port is closed.  This condition
+        * can be reached when a console port is not yet connected (no
+        * tty is spawned) and the host sends out data to console
+        * ports.  For generic serial ports, the host won't
+        * (shouldn't) send data till the guest is connected.
+        */
+       if (!port->guest_connected)
+               discard_port_data(port);
+
+       spin_unlock_irqrestore(&port->inbuf_lock, flags);
+
+       wake_up_interruptible(&port->waitqueue);
+
+       /* Send a SIGIO indicating new data in case the process asked for it */
+       send_sigio_to_port(port);
+
+       if (is_console_port(port) && hvc_poll(port->cons.hvc))
+               hvc_kick();
+}
+
+static void control_intr(struct virtqueue *vq)
+{
+       struct ports_device *portdev;
+
+       portdev = vq->vdev->priv;
+       schedule_work(&portdev->control_work);
+}
+
+static void config_intr(struct virtio_device *vdev)
+{
+       struct ports_device *portdev;
+
+       portdev = vdev->priv;
+
+       if (!use_multiport(portdev)) {
+               struct port *port;
+               u16 rows, cols;
+
+               vdev->config->get(vdev,
+                                 offsetof(struct virtio_console_config, cols),
+                                 &cols, sizeof(u16));
+               vdev->config->get(vdev,
+                                 offsetof(struct virtio_console_config, rows),
+                                 &rows, sizeof(u16));
+
+               port = find_port_by_id(portdev, 0);
+               set_console_size(port, rows, cols);
+
+               /*
+                * We'll use this way of resizing only for legacy
+                * support.  For newer userspace
+                * (VIRTIO_CONSOLE_F_MULTPORT+), use control messages
+                * to indicate console size changes so that it can be
+                * done per-port.
+                */
+               resize_console(port);
+       }
+}
+
+static int init_vqs(struct ports_device *portdev)
+{
+       vq_callback_t **io_callbacks;
+       char **io_names;
+       struct virtqueue **vqs;
+       u32 i, j, nr_ports, nr_queues;
+       int err;
+
+       nr_ports = portdev->config.max_nr_ports;
+       nr_queues = use_multiport(portdev) ? (nr_ports + 1) * 2 : 2;
+
+       vqs = kmalloc(nr_queues * sizeof(struct virtqueue *), GFP_KERNEL);
+       io_callbacks = kmalloc(nr_queues * sizeof(vq_callback_t *), GFP_KERNEL);
+       io_names = kmalloc(nr_queues * sizeof(char *), GFP_KERNEL);
+       portdev->in_vqs = kmalloc(nr_ports * sizeof(struct virtqueue *),
+                                 GFP_KERNEL);
+       portdev->out_vqs = kmalloc(nr_ports * sizeof(struct virtqueue *),
+                                  GFP_KERNEL);
+       if (!vqs || !io_callbacks || !io_names || !portdev->in_vqs ||
+                       !portdev->out_vqs) {
+               err = -ENOMEM;
+               goto free;
+       }
+
+       /*
+        * For backward compat (newer host but older guest), the host
+        * spawns a console port first and also inits the vqs for port
+        * 0 before others.
+        */
+       j = 0;
+       io_callbacks[j] = in_intr;
+       io_callbacks[j + 1] = NULL;
+       io_names[j] = "input";
+       io_names[j + 1] = "output";
+       j += 2;
+
+       if (use_multiport(portdev)) {
+               io_callbacks[j] = control_intr;
+               io_callbacks[j + 1] = NULL;
+               io_names[j] = "control-i";
+               io_names[j + 1] = "control-o";
+
+               for (i = 1; i < nr_ports; i++) {
+                       j += 2;
+                       io_callbacks[j] = in_intr;
+                       io_callbacks[j + 1] = NULL;
+                       io_names[j] = "input";
+                       io_names[j + 1] = "output";
+               }
+       }
+       /* Find the queues. */
+       err = portdev->vdev->config->find_vqs(portdev->vdev, nr_queues, vqs,
+                                             io_callbacks,
+                                             (const char **)io_names);
+       if (err)
+               goto free;
+
+       j = 0;
+       portdev->in_vqs[0] = vqs[0];
+       portdev->out_vqs[0] = vqs[1];
+       j += 2;
+       if (use_multiport(portdev)) {
+               portdev->c_ivq = vqs[j];
+               portdev->c_ovq = vqs[j + 1];
+
+               for (i = 1; i < nr_ports; i++) {
+                       j += 2;
+                       portdev->in_vqs[i] = vqs[j];
+                       portdev->out_vqs[i] = vqs[j + 1];
+               }
+       }
+       kfree(io_names);
+       kfree(io_callbacks);
+       kfree(vqs);
+
+       return 0;
+
+free:
+       kfree(portdev->out_vqs);
+       kfree(portdev->in_vqs);
+       kfree(io_names);
+       kfree(io_callbacks);
+       kfree(vqs);
+
+       return err;
+}
+
+static const struct file_operations portdev_fops = {
+       .owner = THIS_MODULE,
+};
+
+/*
+ * Once we're further in boot, we get probed like any other virtio
+ * device.
+ *
+ * If the host also supports multiple console ports, we check the
+ * config space to see how many ports the host has spawned.  We
+ * initialize each port found.
+ */
+static int __devinit virtcons_probe(struct virtio_device *vdev)
+{
+       struct ports_device *portdev;
+       int err;
+       bool multiport;
+
+       portdev = kmalloc(sizeof(*portdev), GFP_KERNEL);
+       if (!portdev) {
+               err = -ENOMEM;
+               goto fail;
+       }
+
+       /* Attach this portdev to this virtio_device, and vice-versa. */
+       portdev->vdev = vdev;
+       vdev->priv = portdev;
+
+       spin_lock_irq(&pdrvdata_lock);
+       portdev->drv_index = pdrvdata.index++;
+       spin_unlock_irq(&pdrvdata_lock);
+
+       portdev->chr_major = register_chrdev(0, "virtio-portsdev",
+                                            &portdev_fops);
+       if (portdev->chr_major < 0) {
+               dev_err(&vdev->dev,
+                       "Error %d registering chrdev for device %u\n",
+                       portdev->chr_major, portdev->drv_index);
+               err = portdev->chr_major;
+               goto free;
+       }
+
+       multiport = false;
+       portdev->config.max_nr_ports = 1;
+       if (virtio_has_feature(vdev, VIRTIO_CONSOLE_F_MULTIPORT)) {
+               multiport = true;
+               vdev->features[0] |= 1 << VIRTIO_CONSOLE_F_MULTIPORT;
+
+               vdev->config->get(vdev, offsetof(struct virtio_console_config,
+                                                max_nr_ports),
+                                 &portdev->config.max_nr_ports,
+                                 sizeof(portdev->config.max_nr_ports));
+       }
+
+       /* Let the Host know we support multiple ports.*/
+       vdev->config->finalize_features(vdev);
+
+       err = init_vqs(portdev);
+       if (err < 0) {
+               dev_err(&vdev->dev, "Error %d initializing vqs\n", err);
+               goto free_chrdev;
+       }
+
+       spin_lock_init(&portdev->ports_lock);
+       INIT_LIST_HEAD(&portdev->ports);
+
+       if (multiport) {
+               unsigned int nr_added_bufs;
+
+               spin_lock_init(&portdev->cvq_lock);
+               INIT_WORK(&portdev->control_work, &control_work_handler);
+
+               nr_added_bufs = fill_queue(portdev->c_ivq, &portdev->cvq_lock);
+               if (!nr_added_bufs) {
+                       dev_err(&vdev->dev,
+                               "Error allocating buffers for control queue\n");
+                       err = -ENOMEM;
+                       goto free_vqs;
+               }
+       } else {
+               /*
+                * For backward compatibility: Create a console port
+                * if we're running on older host.
+                */
+               add_port(portdev, 0);
+       }
+
+       spin_lock_irq(&pdrvdata_lock);
+       list_add_tail(&portdev->list, &pdrvdata.portdevs);
+       spin_unlock_irq(&pdrvdata_lock);
+
+       __send_control_msg(portdev, VIRTIO_CONSOLE_BAD_ID,
+                          VIRTIO_CONSOLE_DEVICE_READY, 1);
+       return 0;
+
+free_vqs:
+       /* The host might want to notify mgmt sw about device add failure */
+       __send_control_msg(portdev, VIRTIO_CONSOLE_BAD_ID,
+                          VIRTIO_CONSOLE_DEVICE_READY, 0);
+       vdev->config->del_vqs(vdev);
+       kfree(portdev->in_vqs);
+       kfree(portdev->out_vqs);
+free_chrdev:
+       unregister_chrdev(portdev->chr_major, "virtio-portsdev");
+free:
+       kfree(portdev);
+fail:
+       return err;
+}
+
+static void virtcons_remove(struct virtio_device *vdev)
+{
+       struct ports_device *portdev;
+       struct port *port, *port2;
+
+       portdev = vdev->priv;
+
+       spin_lock_irq(&pdrvdata_lock);
+       list_del(&portdev->list);
+       spin_unlock_irq(&pdrvdata_lock);
+
+       /* Disable interrupts for vqs */
+       vdev->config->reset(vdev);
+       /* Finish up work that's lined up */
+       cancel_work_sync(&portdev->control_work);
+
+       list_for_each_entry_safe(port, port2, &portdev->ports, list)
+               unplug_port(port);
+
+       unregister_chrdev(portdev->chr_major, "virtio-portsdev");
+
+       /*
+        * When yanking out a device, we immediately lose the
+        * (device-side) queues.  So there's no point in keeping the
+        * guest side around till we drop our final reference.  This
+        * also means that any ports which are in an open state will
+        * have to just stop using the port, as the vqs are going
+        * away.
+        */
+       if (use_multiport(portdev)) {
+               struct port_buffer *buf;
+               unsigned int len;
+
+               while ((buf = virtqueue_get_buf(portdev->c_ivq, &len)))
+                       free_buf(buf);
+
+               while ((buf = virtqueue_detach_unused_buf(portdev->c_ivq)))
+                       free_buf(buf);
+       }
+
+       vdev->config->del_vqs(vdev);
+       kfree(portdev->in_vqs);
+       kfree(portdev->out_vqs);
+
+       kfree(portdev);
+}
+
+static struct virtio_device_id id_table[] = {
+       { VIRTIO_ID_CONSOLE, VIRTIO_DEV_ANY_ID },
+       { 0 },
+};
+
+static unsigned int features[] = {
+       VIRTIO_CONSOLE_F_SIZE,
+       VIRTIO_CONSOLE_F_MULTIPORT,
+};
+
+static struct virtio_driver virtio_console = {
+       .feature_table = features,
+       .feature_table_size = ARRAY_SIZE(features),
+       .driver.name =  KBUILD_MODNAME,
+       .driver.owner = THIS_MODULE,
+       .id_table =     id_table,
+       .probe =        virtcons_probe,
+       .remove =       virtcons_remove,
+       .config_changed = config_intr,
+};
+
+static int __init init(void)
+{
+       int err;
+
+       pdrvdata.class = class_create(THIS_MODULE, "virtio-ports");
+       if (IS_ERR(pdrvdata.class)) {
+               err = PTR_ERR(pdrvdata.class);
+               pr_err("Error %d creating virtio-ports class\n", err);
+               return err;
+       }
+
+       pdrvdata.debugfs_dir = debugfs_create_dir("virtio-ports", NULL);
+       if (!pdrvdata.debugfs_dir) {
+               pr_warning("Error %ld creating debugfs dir for virtio-ports\n",
+                          PTR_ERR(pdrvdata.debugfs_dir));
+       }
+       INIT_LIST_HEAD(&pdrvdata.consoles);
+       INIT_LIST_HEAD(&pdrvdata.portdevs);
+
+       return register_virtio_driver(&virtio_console);
+}
+
+static void __exit fini(void)
+{
+       unregister_virtio_driver(&virtio_console);
+
+       class_destroy(pdrvdata.class);
+       if (pdrvdata.debugfs_dir)
+               debugfs_remove_recursive(pdrvdata.debugfs_dir);
+}
+module_init(init);
+module_exit(fini);
+
+MODULE_DEVICE_TABLE(virtio, id_table);
+MODULE_DESCRIPTION("Virtio console driver");
+MODULE_LICENSE("GPL");