/*
* Copyright (C) 2006, 2007, 2009 Rusty Russell, IBM Corporation
- * Copyright (C) 2009, 2010 Red Hat, Inc.
+ * Copyright (C) 2009, 2010, 2011 Red Hat, Inc.
+ * Copyright (C) 2009, 2010, 2011 Amit Shah <amit.shah@redhat.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
*/
#include <linux/cdev.h>
#include <linux/debugfs.h>
+#include <linux/completion.h>
#include <linux/device.h>
#include <linux/err.h>
+#include <linux/freezer.h>
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/list.h>
#include <linux/virtio_console.h>
#include <linux/wait.h>
#include <linux/workqueue.h>
-#include "hvc_console.h"
+#include <linux/module.h>
+#include "../tty/hvc/hvc_console.h"
/*
* This is a global struct for storing common data for all the devices
/* 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;
static struct ports_driver_data pdrvdata;
DEFINE_SPINLOCK(pdrvdata_lock);
+DECLARE_COMPLETION(early_console_added);
/* This struct holds information that's relevant only for console ports */
struct console {
/* 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
* 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
int chr_major;
};
+struct port_stats {
+ unsigned long bytes_sent, bytes_received, bytes_discarded;
+};
+
/* This struct holds the per-port data */
struct port {
/* Next port in the list, head is in the ports_device */
*/
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;
struct dentry *debugfs_file;
/*
+ * Keep count of the bytes sent, received and discarded for
+ * this port for accounting and debugging purposes. These
+ * counts are not reset across port open / close events.
+ */
+ struct port_stats stats;
+
+ /*
* 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 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;
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;
}
/* Callers should take appropriate locks */
-static void *get_inbuf(struct port *port)
+static struct port_buffer *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 (port->inbuf)
+ return port->inbuf;
+
+ buf = virtqueue_get_buf(port->in_vq, &len);
if (buf) {
buf->len = len;
buf->offset = 0;
+ port->stats.bytes_received += len;
}
return buf;
}
sg_init_one(sg, buf->buf, buf->size);
- ret = virtqueue_add_buf(vq, sg, 0, 1, buf);
+ ret = virtqueue_add_buf(vq, sg, 0, 1, buf, GFP_ATOMIC);
virtqueue_kick(vq);
return ret;
}
static void discard_port_data(struct port *port)
{
struct port_buffer *buf;
- struct virtqueue *vq;
- unsigned int len;
- int ret;
+ unsigned int err;
- vq = port->in_vq;
- if (port->inbuf)
- buf = port->inbuf;
- else
- buf = virtqueue_get_buf(vq, &len);
+ if (!port->portdev) {
+ /* Device has been unplugged. vqs are already gone. */
+ return;
+ }
+ buf = get_inbuf(port);
- ret = 0;
+ err = 0;
while (buf) {
- if (add_inbuf(vq, buf) < 0) {
- ret++;
+ port->stats.bytes_discarded += buf->len - buf->offset;
+ if (add_inbuf(port->in_vq, buf) < 0) {
+ err++;
free_buf(buf);
}
- buf = virtqueue_get_buf(vq, &len);
+ port->inbuf = NULL;
+ buf = get_inbuf(port);
}
- port->inbuf = NULL;
- if (ret)
+ if (err)
dev_warn(port->dev, "Errors adding %d buffers back to vq\n",
- ret);
+ err);
}
static bool port_has_data(struct port *port)
unsigned long flags;
bool ret;
+ ret = false;
spin_lock_irqsave(&port->inbuf_lock, flags);
- if (port->inbuf) {
- ret = true;
- goto out;
- }
port->inbuf = get_inbuf(port);
- if (port->inbuf) {
+ if (port->inbuf)
ret = true;
- goto out;
- }
- ret = false;
-out:
+
spin_unlock_irqrestore(&port->inbuf_lock, flags);
return ret;
}
vq = portdev->c_ovq;
sg_init_one(sg, &cpkt, sizeof(cpkt));
- if (virtqueue_add_buf(vq, sg, 1, 0, &cpkt) >= 0) {
+ if (virtqueue_add_buf(vq, sg, 1, 0, &cpkt, GFP_ATOMIC) >= 0) {
virtqueue_kick(vq);
while (!virtqueue_get_buf(vq, &len))
cpu_relax();
static ssize_t send_control_msg(struct port *port, unsigned int event,
unsigned int value)
{
- return __send_control_msg(port->portdev, port->id, event, 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;
}
-static ssize_t send_buf(struct port *port, void *in_buf, size_t in_count)
+/* Callers must take the port->outvq_lock */
+static void reclaim_consumed_buffers(struct port *port)
+{
+ void *buf;
+ unsigned int len;
+
+ if (!port->portdev) {
+ /* Device has been unplugged. vqs are already gone. */
+ return;
+ }
+ 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);
+ ret = virtqueue_add_buf(out_vq, sg, 1, 0, in_buf, GFP_ATOMIC);
/* Tell Host to go! */
virtqueue_kick(out_vq);
if (ret < 0) {
in_count = 0;
- goto fail;
+ goto done;
}
- /* Wait till the host acknowledges it pushed out the data we sent. */
+ 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();
-fail:
- /* We're expected to return the amount of data we wrote */
+done:
+ spin_unlock_irqrestore(&port->outvq_lock, flags);
+
+ port->stats.bytes_sent += in_count;
+ /*
+ * We're expected to return the amount of data we wrote -- all
+ * of it
+ */
return in_count;
}
}
/* The condition that must be true for polling to end */
-static bool wait_is_over(struct port *port)
+static bool will_read_block(struct port *port)
{
- return port_has_data(port) || !port->host_connected;
+ 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,
if (filp->f_flags & O_NONBLOCK)
return -EAGAIN;
- ret = wait_event_interruptible(port->waitqueue,
- wait_is_over(port));
+ ret = wait_event_freezable(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.
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_freezable(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);
goto free_buf;
}
- ret = send_buf(port, buf, count);
+ /*
+ * 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;
}
port = filp->private_data;
poll_wait(filp, &port->waitqueue, wait);
+ if (!port->guest_connected) {
+ /* Port got unplugged */
+ return POLLHUP;
+ }
ret = 0;
- if (port->inbuf)
+ if (!will_read_block(port))
ret |= POLLIN | POLLRDNORM;
- if (port->host_connected)
+ 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;
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;
}
{
struct cdev *cdev = inode->i_cdev;
struct port *port;
+ int ret;
- port = container_of(cdev, struct port, cdev);
+ 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))
- return -ENXIO;
+ 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);
- return -EMFILE;
+ 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);
}
/*
.write = port_fops_write,
.poll = port_fops_poll,
.release = port_fops_release,
+ .fasync = port_fops_fasync,
+ .llseek = no_llseek,
};
/*
if (!port)
return -EPIPE;
- return send_buf(port, (void *)buf, count);
+ return send_buf(port, (void *)buf, count, false);
}
/*
static void resize_console(struct port *port)
{
struct virtio_device *vdev;
- struct winsize ws;
/* The port could have been hot-unplugged */
- if (!port)
+ if (!port || !is_console_port(port))
return;
vdev = port->portdev->vdev;
- if (virtio_has_feature(vdev, VIRTIO_CONSOLE_F_SIZE)) {
- vdev->config->get(vdev,
- offsetof(struct virtio_console_config, cols),
- &ws.ws_col, sizeof(u16));
- vdev->config->get(vdev,
- offsetof(struct virtio_console_config, rows),
- &ws.ws_row, sizeof(u16));
- hvc_resize(port->cons.hvc, ws);
- }
+ 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 */
.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)
{
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,
+ "bytes_sent: %lu\n", port->stats.bytes_sent);
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "bytes_received: %lu\n",
+ port->stats.bytes_received);
+ out_offset += snprintf(buf + out_offset, out_count - out_offset,
+ "bytes_discarded: %lu\n",
+ port->stats.bytes_discarded);
+ 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,
static const struct file_operations port_debugfs_ops = {
.owner = THIS_MODULE,
- .open = debugfs_open,
+ .open = simple_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;
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];
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->stats = (struct port_stats) { 0 };
+
+ port->outvq_full = false;
port->in_vq = portdev->in_vqs[port->id];
port->out_vq = portdev->out_vqs[port->id];
- cdev_init(&port->cdev, &port_fops);
+ 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);
+ 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_port;
+ goto free_cdev;
}
port->dev = device_create(pdrvdata.class, &port->portdev->vdev->dev,
devt, port, "vport%up%u",
}
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. */
free_device:
device_destroy(pdrvdata.class, port->dev->devt);
free_cdev:
- cdev_del(&port->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(port, VIRTIO_CONSOLE_PORT_READY, 0);
+ __send_control_msg(portdev, id, VIRTIO_CONSOLE_PORT_READY, 0);
return err;
}
-/* Remove all port-specific data. */
-static int remove_port(struct port *port)
+/* 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);
+}
+
+static void remove_port_data(struct port *port)
{
struct port_buffer *buf;
+ /* 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);
+}
+
+/*
+ * 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)
+{
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
}
- if (port->guest_connected)
- send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 0);
-
- sysfs_remove_group(&port->dev->kobj, &port_attribute_group);
- device_destroy(pdrvdata.class, port->dev->devt);
- cdev_del(&port->cdev);
-
- /* Remove unused data this port might have received. */
- discard_port_data(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);
- kfree(port->name);
+ remove_port_data(port);
- debugfs_remove(port->debugfs_file);
+ /*
+ * 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;
- kfree(port);
- return 0;
+ /*
+ * 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 */
add_port(portdev, cpkt->id);
break;
case VIRTIO_CONSOLE_PORT_REMOVE:
- remove_port(port);
+ unplug_port(port);
break;
case VIRTIO_CONSOLE_CONSOLE_PORT:
if (!cpkt->value)
break;
init_port_console(port);
+ complete(&early_console_added);
/*
* Could remove the port here in case init fails - but
* have to notify the host first.
*/
break;
- case VIRTIO_CONSOLE_RESIZE:
+ 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:
/*
+ * If we woke up after hibernation, we can get this
+ * again. Skip it in that case.
+ */
+ if (port->name)
+ break;
+
+ /*
* Skip the size of the header and the cpkt to get the size
* of the name that was sent
*/
spin_unlock(&portdev->cvq_lock);
}
+static void out_intr(struct virtqueue *vq)
+{
+ struct port *port;
+
+ port = find_port_by_vq(vq->vdev->priv, vq);
+ if (!port)
+ return;
+
+ wake_up_interruptible(&port->waitqueue);
+}
+
static void in_intr(struct virtqueue *vq)
{
struct port *port;
return;
spin_lock_irqsave(&port->inbuf_lock, flags);
- if (!port->inbuf)
- port->inbuf = get_inbuf(port);
+ port->inbuf = get_inbuf(port);
/*
* Don't queue up data when port is closed. This condition
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();
}
portdev = vdev->priv;
- /*
- * 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(find_port_by_id(portdev, 0));
+ 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)
nr_queues = use_multiport(portdev) ? (nr_ports + 1) * 2 : 2;
vqs = kmalloc(nr_queues * sizeof(struct virtqueue *), GFP_KERNEL);
- if (!vqs) {
- err = -ENOMEM;
- goto fail;
- }
io_callbacks = kmalloc(nr_queues * sizeof(vq_callback_t *), GFP_KERNEL);
- if (!io_callbacks) {
- err = -ENOMEM;
- goto free_vqs;
- }
io_names = kmalloc(nr_queues * sizeof(char *), GFP_KERNEL);
- if (!io_names) {
- err = -ENOMEM;
- goto free_callbacks;
- }
portdev->in_vqs = kmalloc(nr_ports * sizeof(struct virtqueue *),
GFP_KERNEL);
- if (!portdev->in_vqs) {
- err = -ENOMEM;
- goto free_names;
- }
portdev->out_vqs = kmalloc(nr_ports * sizeof(struct virtqueue *),
GFP_KERNEL);
- if (!portdev->out_vqs) {
+ if (!vqs || !io_callbacks || !io_names || !portdev->in_vqs ||
+ !portdev->out_vqs) {
err = -ENOMEM;
- goto free_invqs;
+ goto free;
}
/*
*/
j = 0;
io_callbacks[j] = in_intr;
- io_callbacks[j + 1] = NULL;
+ io_callbacks[j + 1] = out_intr;
io_names[j] = "input";
io_names[j + 1] = "output";
j += 2;
for (i = 1; i < nr_ports; i++) {
j += 2;
io_callbacks[j] = in_intr;
- io_callbacks[j + 1] = NULL;
+ io_callbacks[j + 1] = out_intr;
io_names[j] = "input";
io_names[j + 1] = "output";
}
io_callbacks,
(const char **)io_names);
if (err)
- goto free_outvqs;
+ goto free;
j = 0;
portdev->in_vqs[0] = vqs[0];
portdev->out_vqs[i] = vqs[j + 1];
}
}
- kfree(io_callbacks);
kfree(io_names);
+ kfree(io_callbacks);
kfree(vqs);
return 0;
-free_names:
- kfree(io_names);
-free_callbacks:
- kfree(io_callbacks);
-free_outvqs:
+free:
kfree(portdev->out_vqs);
-free_invqs:
kfree(portdev->in_vqs);
-free_vqs:
+ kfree(io_names);
+ kfree(io_callbacks);
kfree(vqs);
-fail:
+
return err;
}
.owner = THIS_MODULE,
};
+static void remove_vqs(struct ports_device *portdev)
+{
+ portdev->vdev->config->del_vqs(portdev->vdev);
+ kfree(portdev->in_vqs);
+ kfree(portdev->out_vqs);
+}
+
+static void remove_controlq_data(struct ports_device *portdev)
+{
+ struct port_buffer *buf;
+ unsigned int len;
+
+ if (!use_multiport(portdev))
+ return;
+
+ while ((buf = virtqueue_get_buf(portdev->c_ivq, &len)))
+ free_buf(buf);
+
+ while ((buf = virtqueue_detach_unused_buf(portdev->c_ivq)))
+ free_buf(buf);
+}
+
/*
* Once we're further in boot, we get probed like any other virtio
* device.
struct ports_device *portdev;
int err;
bool multiport;
+ bool early = early_put_chars != NULL;
+
+ /* Ensure to read early_put_chars now */
+ barrier();
portdev = kmalloc(sizeof(*portdev), GFP_KERNEL);
if (!portdev) {
multiport = false;
portdev->config.max_nr_ports = 1;
- if (virtio_has_feature(vdev, VIRTIO_CONSOLE_F_MULTIPORT)) {
+ if (virtio_config_val(vdev, VIRTIO_CONSOLE_F_MULTIPORT,
+ offsetof(struct virtio_console_config,
+ max_nr_ports),
+ &portdev->config.max_nr_ports) == 0)
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) {
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);
+
+ /*
+ * If there was an early virtio console, assume that there are no
+ * other consoles. We need to wait until the hvc_alloc matches the
+ * hvc_instantiate, otherwise tty_open will complain, resulting in
+ * a "Warning: unable to open an initial console" boot failure.
+ * Without multiport this is done in add_port above. With multiport
+ * this might take some host<->guest communication - thus we have to
+ * wait.
+ */
+ if (multiport && early)
+ wait_for_completion(&early_console_added);
+
return 0;
free_vqs:
- vdev->config->del_vqs(vdev);
- kfree(portdev->in_vqs);
- kfree(portdev->out_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);
+ remove_vqs(portdev);
free_chrdev:
unregister_chrdev(portdev->chr_major, "virtio-portsdev");
free:
kfree(portdev);
fail:
- /* 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);
return err;
}
{
struct ports_device *portdev;
struct port *port, *port2;
- struct port_buffer *buf;
- unsigned int len;
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)
- remove_port(port);
+ unplug_port(port);
unregister_chrdev(portdev->chr_major, "virtio-portsdev");
- 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);
-
+ /*
+ * 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.
+ */
+ remove_controlq_data(portdev);
+ remove_vqs(portdev);
kfree(portdev);
}
VIRTIO_CONSOLE_F_MULTIPORT,
};
+#ifdef CONFIG_PM
+static int virtcons_freeze(struct virtio_device *vdev)
+{
+ struct ports_device *portdev;
+ struct port *port;
+
+ portdev = vdev->priv;
+
+ vdev->config->reset(vdev);
+
+ virtqueue_disable_cb(portdev->c_ivq);
+ cancel_work_sync(&portdev->control_work);
+ /*
+ * Once more: if control_work_handler() was running, it would
+ * enable the cb as the last step.
+ */
+ virtqueue_disable_cb(portdev->c_ivq);
+ remove_controlq_data(portdev);
+
+ list_for_each_entry(port, &portdev->ports, list) {
+ virtqueue_disable_cb(port->in_vq);
+ virtqueue_disable_cb(port->out_vq);
+ /*
+ * We'll ask the host later if the new invocation has
+ * the port opened or closed.
+ */
+ port->host_connected = false;
+ remove_port_data(port);
+ }
+ remove_vqs(portdev);
+
+ return 0;
+}
+
+static int virtcons_restore(struct virtio_device *vdev)
+{
+ struct ports_device *portdev;
+ struct port *port;
+ int ret;
+
+ portdev = vdev->priv;
+
+ ret = init_vqs(portdev);
+ if (ret)
+ return ret;
+
+ if (use_multiport(portdev))
+ fill_queue(portdev->c_ivq, &portdev->cvq_lock);
+
+ list_for_each_entry(port, &portdev->ports, list) {
+ port->in_vq = portdev->in_vqs[port->id];
+ port->out_vq = portdev->out_vqs[port->id];
+
+ fill_queue(port->in_vq, &port->inbuf_lock);
+
+ /* Get port open/close status on the host */
+ send_control_msg(port, VIRTIO_CONSOLE_PORT_READY, 1);
+
+ /*
+ * If a port was open at the time of suspending, we
+ * have to let the host know that it's still open.
+ */
+ if (port->guest_connected)
+ send_control_msg(port, VIRTIO_CONSOLE_PORT_OPEN, 1);
+ }
+ return 0;
+}
+#endif
+
static struct virtio_driver virtio_console = {
.feature_table = features,
.feature_table_size = ARRAY_SIZE(features),
.probe = virtcons_probe,
.remove = virtcons_remove,
.config_changed = config_intr,
+#ifdef CONFIG_PM
+ .freeze = virtcons_freeze,
+ .restore = virtcons_restore,
+#endif
};
static int __init init(void)
PTR_ERR(pdrvdata.debugfs_dir));
}
INIT_LIST_HEAD(&pdrvdata.consoles);
+ INIT_LIST_HEAD(&pdrvdata.portdevs);
return register_virtio_driver(&virtio_console);
}
projects / linux-flexiantxendom0-3.2.10.git / blobdiff