v2.4.10.4 -> v2.4.10.5

[linux-flexiantxendom0-3.2.10.git] / drivers / scsi / aic7xxx / aic7xxx_linux.c

/*
 * Adaptec AIC7xxx device driver for Linux.
 *
 * $Id: //depot/src/linux/drivers/scsi/aic7xxx/aic7xxx_linux.c#72 $
 *
 * Copyright (c) 1994 John Aycock
 *   The University of Calgary Department of Computer Science.
 *
 * 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, 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; see the file COPYING.  If not, write to
 * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * Sources include the Adaptec 1740 driver (aha1740.c), the Ultrastor 24F
 * driver (ultrastor.c), various Linux kernel source, the Adaptec EISA
 * config file (!adp7771.cfg), the Adaptec AHA-2740A Series User's Guide,
 * the Linux Kernel Hacker's Guide, Writing a SCSI Device Driver for Linux,
 * the Adaptec 1542 driver (aha1542.c), the Adaptec EISA overlay file
 * (adp7770.ovl), the Adaptec AHA-2740 Series Technical Reference Manual,
 * the Adaptec AIC-7770 Data Book, the ANSI SCSI specification, the
 * ANSI SCSI-2 specification (draft 10c), ...
 *
 * --------------------------------------------------------------------------
 *
 *  Modifications by Daniel M. Eischen (deischen@iworks.InterWorks.org):
 *
 *  Substantially modified to include support for wide and twin bus
 *  adapters, DMAing of SCBs, tagged queueing, IRQ sharing, bug fixes,
 *  SCB paging, and other rework of the code.
 *
 * --------------------------------------------------------------------------
 * Copyright (c) 1994, 1995, 1996, 1997, 1998, 1999, 2000 Justin T. Gibbs.
 * Copyright (c) 2000 Adaptec Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification.
 * 2. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * Alternatively, this software may be distributed under the terms of the
 * GNU General Public License ("GPL").
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *---------------------------------------------------------------------------
 *
 *  Thanks also go to (in alphabetical order) the following:
 *
 *    Rory Bolt     - Sequencer bug fixes
 *    Jay Estabrook - Initial DEC Alpha support
 *    Doug Ledford  - Much needed abort/reset bug fixes
 *    Kai Makisara  - DMAing of SCBs
 *
 *  A Boot time option was also added for not resetting the scsi bus.
 *
 *    Form:  aic7xxx=extended
 *           aic7xxx=no_reset
 *           aic7xxx=ultra
 *           aic7xxx=irq_trigger:[0,1]  # 0 edge, 1 level
 *           aic7xxx=verbose
 *
 *  Daniel M. Eischen, deischen@iworks.InterWorks.org, 1/23/97
 *
 *  Id: aic7xxx.c,v 4.1 1997/06/12 08:23:42 deang Exp
 */

/*
 * Further driver modifications made by Doug Ledford <dledford@redhat.com>
 *
 * Copyright (c) 1997-1999 Doug Ledford
 *
 * These changes are released under the same licensing terms as the FreeBSD
 * driver written by Justin Gibbs.  Please see his Copyright notice above
 * for the exact terms and conditions covering my changes as well as the
 * warranty statement.
 *
 * Modifications made to the aic7xxx.c,v 4.1 driver from Dan Eischen include
 * but are not limited to:
 *
 *  1: Import of the latest FreeBSD sequencer code for this driver
 *  2: Modification of kernel code to accomodate different sequencer semantics
 *  3: Extensive changes throughout kernel portion of driver to improve
 *     abort/reset processing and error hanndling
 *  4: Other work contributed by various people on the Internet
 *  5: Changes to printk information and verbosity selection code
 *  6: General reliability related changes, especially in IRQ management
 *  7: Modifications to the default probe/attach order for supported cards
 *  8: SMP friendliness has been improved
 *
 */

/*
 * The next three defines are user configurable.  These should be the only
 * defines a user might need to get in here and change.  There are other
 * defines buried deeper in the code, but those really shouldn't need touched
 * under normal conditions.
 */

#include <linux/module.h>

#include "aic7xxx_osm.h"
#include "aic7xxx_inline.h"

#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,3,0)
#include <linux/init.h>         /* __setup */
#endif

#include "../sd.h"              /* For geometry detection */

#include <linux/mm.h>           /* For fetching system memory size */

/*
 * To generate the correct addresses for the controller to issue
 * on the bus.  Originally added for DEC Alpha support.
 */
#define VIRT_TO_BUS(a) (uint32_t)virt_to_bus((void *)(a))

#if LINUX_VERSION_CODE < KERNEL_VERSION(2,3,0)
struct proc_dir_entry proc_scsi_aic7xxx = {
        PROC_SCSI_AIC7XXX, 7, "aic7xxx",
        S_IFDIR | S_IRUGO | S_IXUGO, 2,
        0, 0, 0, NULL, NULL, NULL, NULL, NULL, NULL, NULL
};
#endif

/*
 * Set this to the delay in seconds after SCSI bus reset.
 * Note, we honor this only for the initial bus reset.
 * The scsi error recovery code performs its own bus settle
 * delay handling for error recovery actions.
 */
#ifdef CONFIG_AIC7XXX_RESET_DELAY_MS
#define AIC7XXX_RESET_DELAY CONFIG_AIC7XXX_RESET_DELAY_MS
#else
#define AIC7XXX_RESET_DELAY 5000
#endif

/*
 * Control collection of SCSI transfer statistics for the /proc filesystem.
 *
 * NOTE: Do NOT enable this when running on kernels version 1.2.x and below.
 * NOTE: This does affect performance since it has to maintain statistics.
 */
#ifdef CONFIG_AIC7XXX_PROC_STATS
#define AIC7XXX_PROC_STATS
#endif

/*
 * To change the default number of tagged transactions allowed per-device,
 * add a line to the lilo.conf file like:
 * append="aic7xxx=verbose,tag_info:{{32,32,32,32},{32,32,32,32}}"
 * which will result in the first four devices on the first two
 * controllers being set to a tagged queue depth of 32.
 *
 * The tag_commands is an array of 16 to allow for wide and twin adapters.
 * Twin adapters will use indexes 0-7 for channel 0, and indexes 8-15
 * for channel 1.
 */
typedef struct {
        uint8_t tag_commands[16];       /* Allow for wide/twin adapters. */
} adapter_tag_info_t;

/*
 * Modify this as you see fit for your system.
 *
 * 0                    tagged queuing disabled
 * 1 <= n <= 253        n == max tags ever dispatched.
 *
 * The driver will throttle the number of commands dispatched to a
 * device if it returns queue full.  For devices with a fixed maximum
 * queue depth, the driver will eventually determine this depth and
 * lock it in (a console message is printed to indicate that a lock
 * has occurred).  On some devices, queue full is returned for a temporary
 * resource shortage.  These devices will return queue full at varying
 * depths.  The driver will throttle back when the queue fulls occur and
 * attempt to slowly increase the depth over time as the device recovers
 * from the resource shortage.
 *
 * In this example, the first line will disable tagged queueing for all
 * the devices on the first probed aic7xxx adapter.
 *
 * The second line enables tagged queueing with 4 commands/LUN for IDs
 * (0, 2-11, 13-15), disables tagged queueing for ID 12, and tells the
 * driver to attempt to use up to 64 tags for ID 1.
 *
 * The third line is the same as the first line.
 *
 * The fourth line disables tagged queueing for devices 0 and 3.  It
 * enables tagged queueing for the other IDs, with 16 commands/LUN
 * for IDs 1 and 4, 127 commands/LUN for ID 8, and 4 commands/LUN for
 * IDs 2, 5-7, and 9-15.
 */

/*
 * NOTE: The below structure is for reference only, the actual structure
 *       to modify in order to change things is just below this comment block.
adapter_tag_info_t aic7xxx_tag_info[] =
{
        {{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}},
        {{4, 64, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 0, 4, 4, 4}},
        {{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}},
        {{0, 16, 4, 0, 16, 4, 4, 4, 127, 4, 4, 4, 4, 4, 4, 4}}
};
*/

#ifdef CONFIG_AIC7XXX_CMDS_PER_DEVICE
#define AIC7XXX_CMDS_PER_DEVICE CONFIG_AIC7XXX_CMDS_PER_DEVICE
#else
#define AIC7XXX_CMDS_PER_DEVICE AHC_MAX_QUEUE
#endif

#define AIC7XXX_CONFIGED_TAG_COMMANDS {                                 \
        AIC7XXX_CMDS_PER_DEVICE, AIC7XXX_CMDS_PER_DEVICE,               \
        AIC7XXX_CMDS_PER_DEVICE, AIC7XXX_CMDS_PER_DEVICE,               \
        AIC7XXX_CMDS_PER_DEVICE, AIC7XXX_CMDS_PER_DEVICE,               \
        AIC7XXX_CMDS_PER_DEVICE, AIC7XXX_CMDS_PER_DEVICE,               \
        AIC7XXX_CMDS_PER_DEVICE, AIC7XXX_CMDS_PER_DEVICE,               \
        AIC7XXX_CMDS_PER_DEVICE, AIC7XXX_CMDS_PER_DEVICE,               \
        AIC7XXX_CMDS_PER_DEVICE, AIC7XXX_CMDS_PER_DEVICE,               \
        AIC7XXX_CMDS_PER_DEVICE, AIC7XXX_CMDS_PER_DEVICE                \
}

/*
 * By default, use the number of commands specified by
 * the users kernel configuration.
 */
static adapter_tag_info_t aic7xxx_tag_info[] =
{
        {AIC7XXX_CONFIGED_TAG_COMMANDS},
        {AIC7XXX_CONFIGED_TAG_COMMANDS},
        {AIC7XXX_CONFIGED_TAG_COMMANDS},
        {AIC7XXX_CONFIGED_TAG_COMMANDS},
        {AIC7XXX_CONFIGED_TAG_COMMANDS},
        {AIC7XXX_CONFIGED_TAG_COMMANDS},
        {AIC7XXX_CONFIGED_TAG_COMMANDS},
        {AIC7XXX_CONFIGED_TAG_COMMANDS},
        {AIC7XXX_CONFIGED_TAG_COMMANDS},
        {AIC7XXX_CONFIGED_TAG_COMMANDS},
        {AIC7XXX_CONFIGED_TAG_COMMANDS},
        {AIC7XXX_CONFIGED_TAG_COMMANDS},
        {AIC7XXX_CONFIGED_TAG_COMMANDS},
        {AIC7XXX_CONFIGED_TAG_COMMANDS},
        {AIC7XXX_CONFIGED_TAG_COMMANDS},
        {AIC7XXX_CONFIGED_TAG_COMMANDS}
};

/*
 * There should be a specific return value for this in scsi.h, but
 * it seems that most drivers ignore it.
 */
#define DID_UNDERFLOW   DID_ERROR

void
ahc_print_path(struct ahc_softc *ahc, struct scb *scb)
{
        printk("(scsi%d:%c:%d:%d): ",
               ahc->platform_data->host->host_no,
               scb != NULL ? SCB_GET_CHANNEL(ahc, scb) : 'X',
               scb != NULL ? SCB_GET_TARGET(ahc, scb) : -1,
               scb != NULL ? SCB_GET_LUN(scb) : -1);
}

/*
 * XXX - these options apply unilaterally to _all_ 274x/284x/294x
 *       cards in the system.  This should be fixed.  Exceptions to this
 *       rule are noted in the comments.
 */

/*
 * Skip the scsi bus reset.  Non 0 make us skip the reset at startup.  This
 * has no effect on any later resets that might occur due to things like
 * SCSI bus timeouts.
 */
static uint32_t aic7xxx_no_reset;

/*
 * Certain PCI motherboards will scan PCI devices from highest to lowest,
 * others scan from lowest to highest, and they tend to do all kinds of
 * strange things when they come into contact with PCI bridge chips.  The
 * net result of all this is that the PCI card that is actually used to boot
 * the machine is very hard to detect.  Most motherboards go from lowest
 * PCI slot number to highest, and the first SCSI controller found is the
 * one you boot from.  The only exceptions to this are when a controller
 * has its BIOS disabled.  So, we by default sort all of our SCSI controllers
 * from lowest PCI slot number to highest PCI slot number.  We also force
 * all controllers with their BIOS disabled to the end of the list.  This
 * works on *almost* all computers.  Where it doesn't work, we have this
 * option.  Setting this option to non-0 will reverse the order of the sort
 * to highest first, then lowest, but will still leave cards with their BIOS
 * disabled at the very end.  That should fix everyone up unless there are
 * really strange cirumstances.
 */
static int aic7xxx_reverse_scan = 0;

/*
 * Should we force EXTENDED translation on a controller.
 *     0 == Use whatever is in the SEEPROM or default to off
 *     1 == Use whatever is in the SEEPROM or default to on
 */
static uint32_t aic7xxx_extended = 0;

/*
 * The IRQ trigger method used on EISA controllers. Does not effect PCI cards.
 *   -1 = Use detected settings.
 *    0 = Force Edge triggered mode.
 *    1 = Force Level triggered mode.
 */
static int aic7xxx_irq_trigger = -1;

/*
 * This variable is used to override the termination settings on a controller.
 * This should not be used under normal conditions.  However, in the case
 * that a controller does not have a readable SEEPROM (so that we can't
 * read the SEEPROM settings directly) and that a controller has a buggered
 * version of the cable detection logic, this can be used to force the
 * correct termination.  It is preferable to use the manual termination
 * settings in the BIOS if possible, but some motherboard controllers store
 * those settings in a format we can't read.  In other cases, auto term
 * should also work, but the chipset was put together with no auto term
 * logic (common on motherboard controllers).  In those cases, we have
 * 32 bits here to work with.  That's good for 8 controllers/channels.  The
 * bits are organized as 4 bits per channel, with scsi0 getting the lowest
 * 4 bits in the int.  A 1 in a bit position indicates the termination setting
 * that corresponds to that bit should be enabled, a 0 is disabled.
 * It looks something like this:
 *
 *    0x0f =  1111-Single Ended Low Byte Termination on/off
 *            ||\-Single Ended High Byte Termination on/off
 *            |\-LVD Low Byte Termination on/off
 *            \-LVD High Byte Termination on/off
 *
 * For non-Ultra2 controllers, the upper 2 bits are not important.  So, to
 * enable both high byte and low byte termination on scsi0, I would need to
 * make sure that the override_term variable was set to 0x03 (bits 0011).
 * To make sure that all termination is enabled on an Ultra2 controller at
 * scsi2 and only high byte termination on scsi1 and high and low byte
 * termination on scsi0, I would set override_term=0xf23 (bits 1111 0010 0011)
 *
 * For the most part, users should never have to use this, that's why I
 * left it fairly cryptic instead of easy to understand.  If you need it,
 * most likely someone will be telling you what your's needs to be set to.
 */
static int aic7xxx_override_term = -1;

/*
 * Certain motherboard chipset controllers tend to screw
 * up the polarity of the term enable output pin.  Use this variable
 * to force the correct polarity for your system.  This is a bitfield variable
 * similar to the previous one, but this one has one bit per channel instead
 * of four.
 *    0 = Force the setting to active low.
 *    1 = Force setting to active high.
 * Most Adaptec cards are active high, several motherboards are active low.
 * To force a 2940 card at SCSI 0 to active high and a motherboard 7895
 * controller at scsi1 and scsi2 to active low, and a 2910 card at scsi3
 * to active high, you would need to set stpwlev=0x9 (bits 1001).
 *
 * People shouldn't need to use this, but if you are experiencing lots of
 * SCSI timeout problems, this may help.  There is one sure way to test what
 * this option needs to be.  Using a boot floppy to boot the system, configure
 * your system to enable all SCSI termination (in the Adaptec SCSI BIOS) and
 * if needed then also pass a value to override_term to make sure that the
 * driver is enabling SCSI termination, then set this variable to either 0
 * or 1.  When the driver boots, make sure there are *NO* SCSI cables
 * connected to your controller.  If it finds and inits the controller
 * without problem, then the setting you passed to stpwlev was correct.  If
 * the driver goes into a reset loop and hangs the system, then you need the
 * other setting for this variable.  If neither setting lets the machine
 * boot then you have definite termination problems that may not be fixable.
 */
static int aic7xxx_stpwlev = -1;

/*
 * Set this to non-0 in order to force the driver to panic the kernel
 * and print out debugging info on a SCSI abort or reset cycle.
 */
static int aic7xxx_panic_on_abort = 0;

/*
 * PCI bus parity checking of the Adaptec controllers.  This is somewhat
 * dubious at best.  To my knowledge, this option has never actually
 * solved a PCI parity problem, but on certain machines with broken PCI
 * chipset configurations, it can generate tons of false error messages.
 * It's included in the driver for completeness.
 *   0 = Shut off PCI parity check
 *  -1 = Normal polarity pci parity checking
 *   1 = reverse polarity pci parity checking
 *
 * NOTE: you can't actually pass -1 on the lilo prompt.  So, to set this
 * variable to -1 you would actually want to simply pass the variable
 * name without a number.  That will invert the 0 which will result in
 * -1.
 */
static int aic7xxx_pci_parity = 0;

/*
 * Set this to a non-0 value to make us dump out the 32 bit instruction
 * registers on the card after completing the sequencer download.  This
 * allows the actual sequencer download to be verified.  It is possible
 * to use this option and still boot up and run your system.  This is
 * only intended for debugging purposes.
 */
static int aic7xxx_dump_sequencer = 0;

/*
 * Certain newer motherboards have put new PCI based devices into the
 * IO spaces that used to typically be occupied by VLB or EISA cards.
 * This overlap can cause these newer motherboards to lock up when scanned
 * for older EISA and VLB devices.  Setting this option to non-0 will
 * cause the driver to skip scanning for any VLB or EISA controllers and
 * only support the PCI controllers.  NOTE: this means that if the kernel
 * os compiled with PCI support disabled, then setting this to non-0
 * would result in never finding any devices :)
 */
int aic7xxx_no_probe;

/*
 * aic7xxx_detect() has been run, so register all device arrivals
 * immediately with the system rather than deferring to the sorted
 * attachment performed by aic7xxx_detect().
 */
int aic7xxx_detect_complete;

/*
 * So that we can set how long each device is given as a selection timeout.
 * The table of values goes like this:
 *   0 - 256ms
 *   1 - 128ms
 *   2 - 64ms
 *   3 - 32ms
 * We default to 256ms because some older devices need a longer time
 * to respond to initial selection.
 */
static int aic7xxx_seltime = 0x00;

/*
 * So that insmod can find the variable and make it point to something
 */
#ifdef MODULE
static char *aic7xxx = NULL;

MODULE_PARM(aic7xxx, "s");

/*
 * Just in case someone uses commas to separate items on the insmod
 * command line, we define a dummy buffer here to avoid having insmod
 * write wild stuff into our code segment
 */
static char dummy_buffer[60] = "Please don't trounce on me insmod!!\n";

#endif

static void ahc_linux_handle_scsi_status(struct ahc_softc *,
                                         struct ahc_linux_device *,
                                         struct scb *);
static void ahc_linux_filter_command(struct ahc_softc*, Scsi_Cmnd*,
                                     struct scb*);
static void ahc_linux_sem_timeout(u_long arg);
static void ahc_linux_freeze_sim_queue(struct ahc_softc *ahc);
static void ahc_linux_release_sim_queue(u_long arg);
static int  ahc_linux_queue_recovery_cmd(Scsi_Cmnd *cmd, scb_flag flag);
static void ahc_linux_initialize_scsi_bus(struct ahc_softc *ahc);
static void ahc_linux_select_queue_depth(struct Scsi_Host *host,
                                         Scsi_Device *scsi_devs);
static void ahc_linux_device_queue_depth(struct ahc_softc *ahc,
                                         Scsi_Device *device);
static struct ahc_linux_target* ahc_linux_alloc_target(struct ahc_softc*,
                                                       u_int, u_int);
static void                     ahc_linux_free_target(struct ahc_softc*,
                                                      struct ahc_linux_target*);
static struct ahc_linux_device* ahc_linux_alloc_device(struct ahc_softc*,
                                                       struct ahc_linux_target*,
                                                       u_int);
static void                     ahc_linux_free_device(struct ahc_softc*,
                                                      struct ahc_linux_device*);
static void ahc_linux_run_device_queue(struct ahc_softc*,
                                       struct ahc_linux_device*);
static void ahc_linux_setup_tag_info(char *p, char *end);
static int ahc_linux_next_unit(void);
static int ahc_linux_halt(struct notifier_block *nb, u_long event, void *buf);

static __inline struct ahc_linux_device*
                     ahc_linux_get_device(struct ahc_softc *ahc, u_int channel,
                                          u_int target, u_int lun, int alloc);
static __inline void ahc_linux_queue_cmd_complete(struct ahc_softc *ahc,
                                                  Scsi_Cmnd *cmd);
static __inline void ahc_linux_run_complete_queue(struct ahc_softc *ahc,
                                                  struct ahc_cmd *acmd);
static __inline void ahc_linux_check_device_queue(struct ahc_softc *ahc,
                                                  struct ahc_linux_device *dev);
static __inline void ahc_linux_sniff_command(struct ahc_softc*, Scsi_Cmnd*,
                                             struct scb*);
static __inline void ahc_linux_unmap_scb(struct ahc_softc*, struct scb*);

static __inline int ahc_linux_map_seg(struct ahc_softc *ahc, struct scb *scb,
                                      struct ahc_dma_seg *sg,
                                      bus_addr_t addr, bus_size_t len);

static __inline struct ahc_linux_device*
ahc_linux_get_device(struct ahc_softc *ahc, u_int channel, u_int target,
               u_int lun, int alloc)
{
        struct ahc_linux_target *targ;
        struct ahc_linux_device *dev;
        u_int target_offset;

        target_offset = target;
        if (channel != 0)
                target_offset += 8;
        targ = ahc->platform_data->targets[target_offset];
        if (targ == NULL) {
                if (alloc != 0) {
                        targ = ahc_linux_alloc_target(ahc, channel, target);
                        if (targ == NULL)
                                return (NULL);
                } else
                        return (NULL);
        }
        dev = targ->devices[lun];
        if (dev == NULL && alloc != 0)
                dev = ahc_linux_alloc_device(ahc, targ, lun);
        return (dev);
}

static __inline void
ahc_linux_queue_cmd_complete(struct ahc_softc *ahc, Scsi_Cmnd *cmd)
{
        /*
         * Typically, the complete queue has very few entries
         * queued to it before the queue is emptied by
         * ahc_linux_run_complete_queue, so sorting the entries
         * by generation number should be inexpensive.
         * We perform the sort so that commands that complete
         * with an error are retuned in the order origionally
         * queued to the controller so that any subsequent retries
         * are performed in order.  The underlying ahc routines do
         * not guarantee the order that aborted commands will be
         * returned to us.
         */
        struct ahc_completeq *completeq;
        struct ahc_cmd *list_cmd;
        struct ahc_cmd *acmd;

        /*
         * If we want the request requeued, make sure there
         * are sufficent retries.  In the old scsi error code,
         * we used to be able to specify a result code that
         * bypassed the retry count.  Now we must use this
         * hack.
         */
        if (cmd->result == (CAM_REQUEUE_REQ << 16))
                cmd->retries--;
        completeq = &ahc->platform_data->completeq;
        list_cmd = TAILQ_FIRST(completeq);
        acmd = (struct ahc_cmd *)cmd;
        while (list_cmd != NULL
            && acmd_scsi_cmd(list_cmd).serial_number
             < acmd_scsi_cmd(acmd).serial_number)
                list_cmd = TAILQ_NEXT(list_cmd, acmd_links.tqe);
        if (list_cmd != NULL)
                TAILQ_INSERT_BEFORE(list_cmd, acmd, acmd_links.tqe);
        else
                TAILQ_INSERT_TAIL(completeq, acmd, acmd_links.tqe);
}

static __inline void
ahc_linux_run_complete_queue(struct ahc_softc *ahc, struct ahc_cmd *acmd)
{       
        u_long done_flags;

        ahc_done_lock(ahc, &done_flags);
        while (acmd != NULL) {
                Scsi_Cmnd *cmd;

                cmd = &acmd_scsi_cmd(acmd);
                acmd = TAILQ_NEXT(acmd, acmd_links.tqe);
                cmd->host_scribble = NULL;
                cmd->scsi_done(cmd);
        }
        ahc_done_unlock(ahc, &done_flags);
}

static __inline void
ahc_linux_check_device_queue(struct ahc_softc *ahc,
                             struct ahc_linux_device *dev)
{
        if ((dev->flags & AHC_DEV_FREEZE_TIL_EMPTY) != 0
         && dev->active == 0) {
                dev->flags &= ~AHC_DEV_FREEZE_TIL_EMPTY;
                dev->qfrozen--;
        }

        if (TAILQ_FIRST(&dev->busyq) == NULL
         || dev->openings == 0 || dev->qfrozen != 0)
                return;

        ahc_linux_run_device_queue(ahc, dev);
}

static __inline void
ahc_linux_run_device_queues(struct ahc_softc *ahc)
{
        struct ahc_linux_device *dev;

        while ((ahc->flags & AHC_RESOURCE_SHORTAGE) == 0
            && ahc->platform_data->qfrozen == 0
            && (dev = TAILQ_FIRST(&ahc->platform_data->device_runq)) != NULL) {
                TAILQ_REMOVE(&ahc->platform_data->device_runq, dev, links);
                dev->flags &= ~AHC_DEV_ON_RUN_LIST;
                ahc_linux_check_device_queue(ahc, dev);
        }
}

static __inline void
ahc_linux_sniff_command(struct ahc_softc *ahc, Scsi_Cmnd *cmd, struct scb *scb)
{
        /*
         * Determine whether we care to filter
         * information out of this command.  If so,
         * pass it on to ahc_linux_filter_command() for more
         * heavy weight processing.
         */
        if (cmd->cmnd[0] == INQUIRY)
                ahc_linux_filter_command(ahc, cmd, scb);
}

static __inline void
ahc_linux_unmap_scb(struct ahc_softc *ahc, struct scb *scb)
{
        Scsi_Cmnd *cmd;

        cmd = scb->io_ctx;
        ahc_sync_sglist(ahc, scb, BUS_DMASYNC_POSTWRITE);
        if (cmd->use_sg != 0) {
                struct scatterlist *sg;

                sg = (struct scatterlist *)cmd->request_buffer;
                pci_unmap_sg(ahc->dev_softc, sg, cmd->use_sg,
                             scsi_to_pci_dma_dir(cmd->sc_data_direction));
        } else if (cmd->request_bufflen != 0)
                pci_unmap_single(ahc->dev_softc,
                                 ahc_le32toh(scb->sg_list[0].addr),
                                 cmd->request_bufflen,
                                 scsi_to_pci_dma_dir(cmd->sc_data_direction));
}

static __inline int
ahc_linux_map_seg(struct ahc_softc *ahc, struct scb *scb,
                  struct ahc_dma_seg *sg, bus_addr_t addr, bus_size_t len)
{
        int      consumed;

        if ((scb->sg_count + 1) > AHC_NSEG)
                panic("Too few segs for dma mapping.  "
                      "Increase AHC_NSEG\n");

        consumed = 1;
        sg->addr = ahc_htole32(addr & 0xFFFFFFFF);
        scb->platform_data->xfer_len += len;
        if (sizeof(bus_addr_t) > 4
         && (ahc->flags & AHC_39BIT_ADDRESSING) != 0) {
                /*
                 * Due to DAC restrictions, we can't
                 * cross a 4GB boundary.
                 */
                if ((addr ^ (addr + len - 1)) & ~0xFFFFFFFF) {
                        struct   ahc_dma_seg *next_sg;
                        uint32_t next_len;

                        printf("Crossed Seg\n");
                        if ((scb->sg_count + 2) > AHC_NSEG)
                                panic("Too few segs for dma mapping.  "
                                      "Increase AHC_NSEG\n");

                        consumed++;
                        next_sg = sg + 1;
                        next_sg->addr = 0;
                        next_len = 0x100000000 - (addr & 0xFFFFFFFF);
                        len -= next_len;
                        next_len |= ((addr >> 8) + 0x1000000) & 0x7F000000;
                        next_sg->len = ahc_htole32(next_len);
                }
                len |= (addr >> 8) & 0x7F000000;
        }
        sg->len = ahc_htole32(len);
        return (consumed);
}

/************************ Shutdown/halt/reboot hook ***************************/
#include <linux/notifier.h>
#include <linux/reboot.h>

static struct notifier_block ahc_linux_notifier = {
        ahc_linux_halt, NULL, 0
};

static int ahc_linux_halt(struct notifier_block *nb, u_long event, void *buf)
{
        struct ahc_softc *ahc;

        TAILQ_FOREACH(ahc, &ahc_tailq, links) {
                ahc_shutdown(ahc);
        }
        return (NOTIFY_OK);
}

/******************************** Macros **************************************/
#define BUILD_SCSIID(ahc, cmd)                                          \
        ((((cmd)->target << TID_SHIFT) & TID)                           \
        | (((cmd)->channel == 0) ? (ahc)->our_id : (ahc)->our_id_b)     \
        | (((cmd)->channel == 0) ? 0 : TWIN_CHNLB))

/******************************** Bus DMA *************************************/
int
ahc_dma_tag_create(struct ahc_softc *ahc, bus_dma_tag_t parent,
                   bus_size_t alignment, bus_size_t boundary,
                   bus_addr_t lowaddr, bus_addr_t highaddr,
                   bus_dma_filter_t *filter, void *filterarg,
                   bus_size_t maxsize, int nsegments,
                   bus_size_t maxsegsz, int flags, bus_dma_tag_t *ret_tag)
{
        bus_dma_tag_t dmat;

        dmat = malloc(sizeof(*dmat), M_DEVBUF, M_NOWAIT);
        if (dmat == NULL)
                return (ENOMEM);

        /*
         * Linux is very simplistic about DMA memory.  For now don't
         * maintain all specification information.  Once Linux supplies
         * better facilities for doing these operations, or the
         * needs of this particular driver change, we might need to do
         * more here.
         */
        dmat->alignment = alignment;
        dmat->boundary = boundary;
        dmat->maxsize = maxsize;
        *ret_tag = dmat;
        return (0);
}

void
ahc_dma_tag_destroy(struct ahc_softc *ahc, bus_dma_tag_t dmat)
{
        free(dmat, M_DEVBUF);
}

int
ahc_dmamem_alloc(struct ahc_softc *ahc, bus_dma_tag_t dmat, void** vaddr,
                 int flags, bus_dmamap_t *mapp)
{
        bus_dmamap_t map;

#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,3,0)
        map = malloc(sizeof(*map), M_DEVBUF, M_NOWAIT);
        if (map == NULL)
                return (ENOMEM);
        /*
         * Although we can dma data above 4GB, our
         * "consistent" memory is below 4GB for
         * space efficiency reasons (only need a 4byte
         * address).  For this reason, we have to reset
         * our dma mask when doing allocations.
         */
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,4,3)
        pci_set_dma_mask(ahc->dev_softc, 0xFFFFFFFF);
#else
        ahc->dev_softc->dma_mask = 0xFFFFFFFF;
#endif
        *vaddr = pci_alloc_consistent(ahc->dev_softc,
                                      dmat->maxsize, &map->bus_addr);
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,4,3)
        pci_set_dma_mask(ahc->dev_softc, ahc->platform_data->hw_dma_mask);
#else
        ahc->dev_softc->dma_mask = ahc->platform_data->hw_dma_mask;
#endif
#else /* LINUX_VERSION_CODE < KERNEL_VERSION(2,3,0) */
        /*
         * At least in 2.2.14, malloc is a slab allocator so all
         * allocations are aligned.  We assume, for these kernel versions
         * that all allocations will be bellow 4Gig, physically contiguous,
         * and accessable via DMA by the controller.
         */
        map = NULL; /* No additional information to store */
        *vaddr = malloc(dmat->maxsize, M_DEVBUF, M_NOWAIT);
#endif
        if (*vaddr == NULL)
                return (ENOMEM);
        *mapp = map;
        return(0);
}

void
ahc_dmamem_free(struct ahc_softc *ahc, bus_dma_tag_t dmat,
                void* vaddr, bus_dmamap_t map)
{
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,3,0)
        pci_free_consistent(ahc->dev_softc, dmat->maxsize,
                            vaddr, map->bus_addr);
#else
        free(vaddr, M_DEVBUF);
#endif
}

int
ahc_dmamap_load(struct ahc_softc *ahc, bus_dma_tag_t dmat, bus_dmamap_t map,
                void *buf, bus_size_t buflen, bus_dmamap_callback_t *cb,
                void *cb_arg, int flags)
{
        /*
         * Assume for now that this will only be used during
         * initialization and not for per-transaction buffer mapping.
         */
        bus_dma_segment_t stack_sg;

#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,3,0)
        stack_sg.ds_addr = map->bus_addr;
#else
        stack_sg.ds_addr = VIRT_TO_BUS(buf);
#endif
        stack_sg.ds_len = dmat->maxsize;
        cb(cb_arg, &stack_sg, /*nseg*/1, /*error*/0);
        return (0);
}

void
ahc_dmamap_destroy(struct ahc_softc *ahc, bus_dma_tag_t dmat, bus_dmamap_t map)
{
        /*
         * The map may is NULL in our < 2.3.X implementation.
         */
        if (map != NULL)
                free(map, M_DEVBUF);
}

int
ahc_dmamap_unload(struct ahc_softc *ahc, bus_dma_tag_t dmat, bus_dmamap_t map)
{
        /* Nothing to do */
        return (0);
}

/********************* Platform Dependent Functions ***************************/
int
ahc_softc_comp(struct ahc_softc *lahc, struct ahc_softc *rahc)
{
        int     value;
        int     rvalue;
        int     lvalue;

        /*
         * Under Linux, cards are ordered as follows:
         *      1) VLB/EISA BIOS enabled devices sorted by BIOS address.
         *      2) PCI devices with BIOS enabled sorted by bus/slot/func.
         *      3) All remaining VLB/EISA devices sorted by ioport.
         *      4) All remaining PCI devices sorted by bus/slot/func.
         */
        value = (lahc->flags & AHC_BIOS_ENABLED)
              - (rahc->flags & AHC_BIOS_ENABLED);
        if (value != 0)
                /* Controllers with BIOS enabled have a *higher* priority */
                return (-value);

        /*
         * Same BIOS setting, now sort based on bus type.
         * EISA and VL controllers sort together.  EISA/VL
         * have higher priority than PCI.
         */
        rvalue = (rahc->chip & AHC_BUS_MASK);
        if (rvalue == AHC_VL)
                rvalue = AHC_EISA;
        lvalue = (lahc->chip & AHC_BUS_MASK);
        if (lvalue == AHC_VL)
                lvalue = AHC_EISA;
        value = lvalue - rvalue;
        if (value != 0)
                return (value);

        /* Still equal.  Sort by BIOS address, ioport, or bus/slot/func. */
        switch (rvalue) {
        case AHC_PCI:
        {
                char primary_channel;

                value = ahc_get_pci_bus(lahc->dev_softc)
                      - ahc_get_pci_bus(rahc->dev_softc);
                if (value != 0)
                        break;
                value = ahc_get_pci_slot(lahc->dev_softc)
                      - ahc_get_pci_slot(rahc->dev_softc);
                if (value != 0)
                        break;
                /*
                 * On multi-function devices, the user can choose
                 * to have function 1 probed before function 0.
                 * Give whichever channel is the primary channel
                 * the lowest priority.
                 */
                primary_channel = (lahc->flags & AHC_PRIMARY_CHANNEL) + 'A';
                value = 1;
                if (lahc->channel == primary_channel)
                        value = -1;
                break;
        }
        case AHC_EISA:
                if ((rahc->flags & AHC_BIOS_ENABLED) != 0) {
                        value = lahc->platform_data->bios_address
                              - rahc->platform_data->bios_address; 
                } else {
                        value = lahc->bsh.ioport
                              - rahc->bsh.ioport; 
                }
                break;
        default:
                panic("ahc_softc_sort: invalid bus type");
        }
        return (value);
}

static void
ahc_linux_setup_tag_info(char *p, char *end)
{
        char    *base;
        char    *tok;
        char    *tok_end;
        char    *tok_end2;
        int      i;
        int      instance;
        int      targ;
        int      done;
        char     tok_list[] = {'.', ',', '{', '}', '\0'};

        if (*p != ':')
                return;

        instance = -1;
        targ = -1;
        done = FALSE;
        base = p;
        /* Forward us just past the ':' */
        tok = base + 1;
        tok_end = strchr(tok, '\0');
        if (tok_end < end)
                *tok_end = ',';
        while (!done) {
                switch (*tok) {
                case '{':
                        if (instance == -1)
                                instance = 0;
                        else if (targ == -1)
                                targ = 0;
                        tok++;
                        break;
                case '}':
                        if (targ != -1)
                                targ = -1;
                        else if (instance != -1)
                                instance = -1;
                        tok++;
                        break;
                case ',':
                case '.':
                        if (instance == -1)
                                done = TRUE;
                        else if (targ >= 0)
                                targ++;
                        else if (instance >= 0)
                                instance++;
                        if ((targ >= AHC_NUM_TARGETS) ||
                            (instance >= NUM_ELEMENTS(aic7xxx_tag_info)))
                                done = TRUE;
                        tok++;
                        if (!done) {
                                base = tok;
                        }
                        break;
                case '\0':
                        done = TRUE;
                        break;
                default:
                        done = TRUE;
                        tok_end = strchr(tok, '\0');
                        for (i = 0; tok_list[i]; i++) {
                                tok_end2 = strchr(tok, tok_list[i]);
                                if ((tok_end2) && (tok_end2 < tok_end)) {
                                        tok_end = tok_end2;
                                        done = FALSE;
                                }
                        }
                        if ((instance >= 0) && (targ >= 0)
                         && (instance < NUM_ELEMENTS(aic7xxx_tag_info))
                         && (targ < AHC_NUM_TARGETS)) {
                                aic7xxx_tag_info[instance].tag_commands[targ] =
                                    simple_strtoul(tok, NULL, 0) & 0xff;
                        }
                        tok = tok_end;
                        break;
                }
        }
        while ((p != base) && (p != NULL))
                p = strtok(NULL, ",.");
}

/*
 * Handle Linux boot parameters. This routine allows for assigning a value
 * to a parameter with a ':' between the parameter and the value.
 * ie. aic7xxx=unpause:0x0A,extended
 */
int
aic7xxx_setup(char *s)
{
        int     i, n;
        char   *p;
        char   *end;

        static struct {
                const char *name;
                uint32_t *flag;
        } options[] = {
                { "extended", &aic7xxx_extended },
                { "no_reset", &aic7xxx_no_reset },
                { "irq_trigger", &aic7xxx_irq_trigger },
                { "verbose", &aic7xxx_verbose },
                { "reverse_scan", &aic7xxx_reverse_scan },
                { "override_term", &aic7xxx_override_term },
                { "stpwlev", &aic7xxx_stpwlev },
                { "no_probe", &aic7xxx_no_probe },
                { "panic_on_abort", &aic7xxx_panic_on_abort },
                { "pci_parity", &aic7xxx_pci_parity },
                { "dump_sequencer", &aic7xxx_dump_sequencer },
                { "seltime", &aic7xxx_seltime },
                { "tag_info", NULL }
        };

        end = strchr(s, '\0');

        for (p = strtok(s, ",."); p; p = strtok(NULL, ",.")) {
                for (i = 0; i < NUM_ELEMENTS(options); i++) {
                        n = strlen(options[i].name);

                        if (strncmp(options[i].name, p, n) != 0)
                                continue;

                        if (strncmp(p, "tag_info", n) == 0) {
                                ahc_linux_setup_tag_info(p + n, end);
                        } else if (p[n] == ':') {
                                *(options[i].flag) =
                                    simple_strtoul(p + n + 1, NULL, 0);
                        } else if (!strncmp(p, "verbose", n)) {
                                *(options[i].flag) = 1;
                        } else {
                                *(options[i].flag) = ~(*(options[i].flag));
                        }
                        break;
                }
        }
        register_reboot_notifier(&ahc_linux_notifier);
        return 1;
}

#if LINUX_VERSION_CODE > KERNEL_VERSION(2,3,0)
__setup("aic7xxx=", aic7xxx_setup);
#endif

int aic7xxx_verbose;

/*
 * Try to detect an Adaptec 7XXX controller.
 */
int
ahc_linux_detect(Scsi_Host_Template *template)
{
        struct  ahc_softc *ahc;
        int     found;

        /*
         * Sanity checking of Linux SCSI data structures so
         * that some of our hacks^H^H^H^H^Hassumptions aren't
         * violated.
         */
        if (offsetof(struct ahc_cmd_internal, end)
          > offsetof(struct scsi_cmnd, host_scribble)) {
                printf("ahc_linux_detect: SCSI data structures changed.\n");
                printf("ahc_linux_detect: Unable to attach\n");
                return (0);
        }
#ifdef MODULE
        /*
         * If we've been passed any parameters, process them now.
         */
        if (aic7xxx)
                aic7xxx_setup(aic7xxx);
        if (dummy_buffer[0] != 'P')
                printk(KERN_WARNING
"aic7xxx: Please read the file /usr/src/linux/drivers/scsi/README.aic7xxx\n"
"aic7xxx: to see the proper way to specify options to the aic7xxx module\n"
"aic7xxx: Specifically, don't use any commas when passing arguments to\n"
"aic7xxx: insmod or else it might trash certain memory areas.\n");
#endif

#if LINUX_VERSION_CODE > KERNEL_VERSION(2,3,0)
        template->proc_name = "aic7xxx";
#else
        template->proc_dir = &proc_scsi_aic7xxx;
#endif
        template->sg_tablesize = AHC_NSEG;

#ifdef CONFIG_PCI
        ahc_linux_pci_probe(template);
#endif

        aic7770_linux_probe(template);

        /*
         * Register with the SCSI layer all
         * controllers we've found.
         */
        found = 0;
        TAILQ_FOREACH(ahc, &ahc_tailq, links) {

                if (ahc_linux_register_host(ahc, template) == 0)
                        found++;
        }
        aic7xxx_detect_complete++;
        return (found);
}

int
ahc_linux_register_host(struct ahc_softc *ahc, Scsi_Host_Template *template)
{
        char  buf[80];
        struct Scsi_Host *host;
        char *new_name;
        u_long s;


        template->name = ahc->description;
        host = scsi_register(template, sizeof(struct ahc_softc *));
        if (host == NULL)
                return (ENOMEM);

        ahc_lock(ahc, &s);
        *((struct ahc_softc **)host->hostdata) = ahc;
        ahc->platform_data->host = host;
        host->can_queue = AHC_MAX_QUEUE;
        host->cmd_per_lun = 2;
        host->sg_tablesize = AHC_NSEG;
        host->select_queue_depths = ahc_linux_select_queue_depth;
        /* XXX No way to communicate the ID for multiple channels */
        host->this_id = ahc->our_id;
        host->irq = ahc->platform_data->irq;
        host->max_id = (ahc->features & AHC_WIDE) ? 16 : 8;
        host->max_channel = (ahc->features & AHC_TWIN) ? 1 : 0;
        host->max_lun = AHC_NUM_LUNS;
        ahc_set_unit(ahc, ahc_linux_next_unit());
        sprintf(buf, "scsi%d", host->host_no);
        new_name = malloc(strlen(buf) + 1, M_DEVBUF, M_NOWAIT);
        if (new_name != NULL) {
                strcpy(new_name, buf);
                ahc_set_name(ahc, new_name);
        }
        host->unique_id = ahc->unit;
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,4,4)
        scsi_set_pci_device(host, ahc->dev_softc);
#endif
        ahc_linux_initialize_scsi_bus(ahc);
        ahc_unlock(ahc, &s);
        return (0);
}

uint64_t
ahc_linux_get_memsize()
{
        struct sysinfo si;

        si_meminfo(&si);
        return (si.totalram << PAGE_SHIFT);
}

/*
 * Find the smallest available unit number to use
 * for a new device.  We don't just use a static
 * count to handle the "repeated hot-(un)plug"
 * scenario.
 */
static int
ahc_linux_next_unit()
{
        struct ahc_softc *ahc;
        int unit;

        unit = 0;
retry:
        TAILQ_FOREACH(ahc, &ahc_tailq, links) {
                if (ahc->unit == unit) {
                        unit++;
                        goto retry;
                }
        }
        return (unit);
}

/*
 * Place the SCSI bus into a known state by either resetting it,
 * or forcing transfer negotiations on the next command to any
 * target.
 */
void
ahc_linux_initialize_scsi_bus(struct ahc_softc *ahc)
{
        int i;
        int numtarg;

        i = 0;
        numtarg = 0;

        if (aic7xxx_no_reset != 0)
                ahc->flags &= ~(AHC_RESET_BUS_A|AHC_RESET_BUS_B);

        if ((ahc->flags & AHC_RESET_BUS_A) != 0)
                ahc_reset_channel(ahc, 'A', /*initiate_reset*/TRUE);
        else
                numtarg = (ahc->features & AHC_WIDE) ? 16 : 8;

        if ((ahc->features & AHC_TWIN) != 0) {

                if ((ahc->flags & AHC_RESET_BUS_B) != 0) {
                        ahc_reset_channel(ahc, 'B', /*initiate_reset*/TRUE);
                } else {
                        if (numtarg == 0)
                                i = 8;
                        numtarg += 8;
                }
        }

        for (; i < numtarg; i++) {
                struct ahc_devinfo devinfo;
                struct ahc_initiator_tinfo *tinfo;
                struct ahc_tmode_tstate *tstate;
                u_int our_id;
                u_int target_id;
                char channel;

                channel = 'A';
                our_id = ahc->our_id;
                target_id = i;
                if (i > 7 && (ahc->features & AHC_TWIN) != 0) {
                        channel = 'B';
                        our_id = ahc->our_id_b;
                        target_id = i % 8;
                }
                tinfo = ahc_fetch_transinfo(ahc, channel, our_id,
                                            target_id, &tstate);
                tinfo->goal = tinfo->user;
                /*
                 * Don't try negotiations that require PPR messages
                 * until we successfully retrieve Inquiry data.
                 */
                tinfo->goal.ppr_options = 0;
                if (tinfo->goal.transport_version > SCSI_REV_2)
                        tinfo->goal.transport_version = SCSI_REV_2;
                ahc_compile_devinfo(&devinfo, our_id, target_id,
                                   CAM_LUN_WILDCARD, channel, ROLE_INITIATOR);
                ahc_update_neg_request(ahc, &devinfo, tstate,
                                       tinfo, /*force*/FALSE);
        }
        /* Give the bus some time to recover */
        if ((ahc->flags & (AHC_RESET_BUS_A|AHC_RESET_BUS_B)) != 0) {
                ahc_linux_freeze_sim_queue(ahc);
                init_timer(&ahc->platform_data->reset_timer);
                ahc->platform_data->reset_timer.data = (u_long)ahc;
                ahc->platform_data->reset_timer.expires =
                    jiffies + (AIC7XXX_RESET_DELAY * HZ)/1000;
                ahc->platform_data->reset_timer.function =
                    ahc_linux_release_sim_queue;
                add_timer(&ahc->platform_data->reset_timer);
        }
}

int
ahc_platform_alloc(struct ahc_softc *ahc, void *platform_arg)
{
        ahc->platform_data =
            malloc(sizeof(struct ahc_platform_data), M_DEVBUF, M_NOWAIT);
        if (ahc->platform_data == NULL)
                return (ENOMEM);
        memset(ahc->platform_data, 0, sizeof(struct ahc_platform_data));
        TAILQ_INIT(&ahc->platform_data->completeq);
        TAILQ_INIT(&ahc->platform_data->device_runq);
        ahc->platform_data->hw_dma_mask = 0xFFFFFFFF;
        ahc_lockinit(ahc);
        ahc_done_lockinit(ahc);
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,3,0)
        init_MUTEX_LOCKED(&ahc->platform_data->eh_sem);
#else
        ahc->platform_data->eh_sem = MUTEX_LOCKED;
#endif
        ahc->seltime = (aic7xxx_seltime & 0x3) << 4;
        ahc->seltime_b = (aic7xxx_seltime & 0x3) << 4;
        return (0);
}

void
ahc_platform_free(struct ahc_softc *ahc)
{
        if (ahc->platform_data != NULL) {
                if (ahc->platform_data->host != NULL)
                        scsi_unregister(ahc->platform_data->host);
                if (ahc->platform_data->irq)
                        free_irq(ahc->platform_data->irq, ahc);
                if (ahc->tag == BUS_SPACE_PIO
                 && ahc->bsh.ioport != 0)
                        release_region(ahc->bsh.ioport, 256);
                if (ahc->tag == BUS_SPACE_MEMIO
                 && ahc->bsh.maddr != NULL) {
                        u_long base_addr;

                        base_addr = (u_long)ahc->bsh.maddr;
                        base_addr &= PAGE_MASK;
                        iounmap((void *)base_addr);
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,4,0)
                        release_mem_region(ahc->platform_data->mem_busaddr,
                                           0x1000);
#endif
                }
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,4,0)
                /* XXX Need an instance detach in the PCI code */
                if (ahc->dev_softc != NULL)
                        ahc->dev_softc->driver = NULL;
#endif
                free(ahc->platform_data, M_DEVBUF);
        }
}

void
ahc_platform_freeze_devq(struct ahc_softc *ahc, struct scb *scb)
{
        ahc_platform_abort_scbs(ahc, SCB_GET_TARGET(ahc, scb),
                                SCB_GET_CHANNEL(ahc, scb),
                                SCB_GET_LUN(scb), SCB_LIST_NULL,
                                ROLE_UNKNOWN, CAM_REQUEUE_REQ);
}

void
ahc_platform_set_tags(struct ahc_softc *ahc, struct ahc_devinfo *devinfo,
                      ahc_queue_alg alg)
{
        struct ahc_linux_device *dev;
        int was_queuing;
        int now_queuing;

        dev = ahc_linux_get_device(ahc, devinfo->channel - 'A',
                                   devinfo->target,
                                   devinfo->lun, /*alloc*/FALSE);
        if (dev == NULL)
                return;
        was_queuing = dev->flags & (AHC_DEV_Q_BASIC|AHC_DEV_Q_TAGGED);
        now_queuing = alg != AHC_QUEUE_NONE;
        if ((dev->flags & AHC_DEV_FREEZE_TIL_EMPTY) == 0
         && (was_queuing != now_queuing)
         && (dev->active != 0)) {
                dev->flags |= AHC_DEV_FREEZE_TIL_EMPTY;
                dev->qfrozen++;
        }

        dev->flags &= ~(AHC_DEV_Q_BASIC|AHC_DEV_Q_TAGGED);
        if (now_queuing) {

                if (!was_queuing) {
                        /*
                         * Start out agressively and allow our
                         * dynamic queue depth algorithm to take
                         * care of the rest.
                         */
                        dev->maxtags = AHC_MAX_QUEUE;
                        dev->openings = dev->maxtags - dev->active;
                }
                if (alg == AHC_QUEUE_TAGGED)
                        dev->flags |= AHC_DEV_Q_TAGGED;
                else
                        dev->flags |= AHC_DEV_Q_BASIC;
        } else {
                /* We can only have one opening */
                dev->maxtags = 0;
                dev->openings =  1 - dev->active;
        }
}

int
ahc_platform_abort_scbs(struct ahc_softc *ahc, int target, char channel,
                        int lun, u_int tag, role_t role, uint32_t status)
{
        int chan;
        int maxchan;
        int targ;
        int maxtarg;
        int clun;
        int maxlun;
        int count;

        if (tag != SCB_LIST_NULL)
                return (0);

        chan = 0;
        if (channel != ALL_CHANNELS) {
                chan = channel - 'A';
                maxchan = chan + 1;
        } else {
                maxchan = (ahc->features & AHC_TWIN) ? 2 : 1;
        }
        targ = 0;
        if (target != CAM_TARGET_WILDCARD) {
                targ = target;
                maxtarg = targ + 1;
        } else {
                maxtarg = (ahc->features & AHC_WIDE) ? 16 : 8;
        }
        clun = 0;
        if (lun != CAM_LUN_WILDCARD) {
                clun = lun;
                maxlun = clun + 1;
        } else {
                maxlun = 16;
        }

        count = 0;
        for (; chan < maxchan; chan++) {
                for (; targ < maxtarg; targ++) {
                        for (; clun < maxlun; clun++) {
                                struct ahc_linux_device *dev;
                                struct ahc_busyq *busyq;
                                struct ahc_cmd *acmd;

                                dev = ahc_linux_get_device(ahc, chan,
                                                           targ, clun,
                                                           /*alloc*/FALSE);
                                if (dev == NULL)
                                        continue;

                                busyq = &dev->busyq;
                                while ((acmd = TAILQ_FIRST(busyq)) != NULL) {
                                        Scsi_Cmnd *cmd;

                                        cmd = &acmd_scsi_cmd(acmd);
                                        TAILQ_REMOVE(busyq, acmd,
                                                     acmd_links.tqe);
                                        count++;
                                        cmd->result = status << 16;
                                        ahc_linux_queue_cmd_complete(ahc, cmd);
                                }
                        }
                }
        }

        return (count);
}

/*
 * Sets the queue depth for each SCSI device hanging
 * off the input host adapter.
 */
static void
ahc_linux_select_queue_depth(struct Scsi_Host * host,
                             Scsi_Device * scsi_devs)
{
        Scsi_Device *device;
        struct  ahc_softc *ahc;
        u_long  flags;
        int     scbnum;

        ahc = *((struct ahc_softc **)host->hostdata);
        ahc_lock(ahc, &flags);
        scbnum = 0;
        for (device = scsi_devs; device != NULL; device = device->next) {
                if (device->host == host) {
                        ahc_linux_device_queue_depth(ahc, device);
                        scbnum += device->queue_depth;
                }
        }
        ahc_unlock(ahc, &flags);
}

/*
 * Determines the queue depth for a given device.
 */
static void
ahc_linux_device_queue_depth(struct ahc_softc *ahc, Scsi_Device * device)
{
        struct  ahc_devinfo devinfo;
        struct  ahc_initiator_tinfo *targ_info;
        struct  ahc_tmode_tstate *tstate;
        uint8_t tags;

        ahc_compile_devinfo(&devinfo,
                            device->channel == 0 ? ahc->our_id : ahc->our_id_b,
                            device->id, device->lun,
                            device->channel == 0 ? 'A' : 'B',
                            ROLE_INITIATOR);
        targ_info = ahc_fetch_transinfo(ahc, devinfo.channel,
                                        devinfo.our_scsiid,
                                        devinfo.target, &tstate);

        tags = 0;
        if (device->tagged_supported != 0
         && (ahc->user_discenable & devinfo.target_mask) != 0) {
                if (ahc->unit >= NUM_ELEMENTS(aic7xxx_tag_info)) {

                        printf("aic7xxx: WARNING, insufficient "
                               "tag_info instances for installed "
                               "controllers. Using defaults\n");
                        printf("aic7xxx: Please update the "
                               "aic7xxx_tag_info array in the "
                               "aic7xxx.c source file.\n");
                        tags = AHC_MAX_QUEUE;
                } else {
                        adapter_tag_info_t *tag_info;

                        tag_info = &aic7xxx_tag_info[ahc->unit];
                        tags = tag_info->tag_commands[devinfo.target_offset];
                        if (tags > AHC_MAX_QUEUE)
                                tags = AHC_MAX_QUEUE;
                }
        }
        if (tags != 0) {
                device->queue_depth = tags;
                ahc_set_tags(ahc, &devinfo, AHC_QUEUE_TAGGED);
                printf("scsi%d:%d:%d:%d: Tagged Queuing enabled.  Depth %d\n",
                       ahc->platform_data->host->host_no, device->channel,
                       device->id, device->lun, tags);
        } else {
                /*
                 * We allow the OS to queue 2 untagged transactions to
                 * us at any time even though we can only execute them
                 * serially on the controller/device.  This should remove
                 * some latency.
                 */
                device->queue_depth = 2;
        }
}

/*
 * Queue an SCB to the controller.
 */
int
ahc_linux_queue(Scsi_Cmnd * cmd, void (*scsi_done) (Scsi_Cmnd *))
{
        struct   ahc_softc *ahc;
        struct   ahc_linux_device *dev;
        u_long   flags;

        ahc = *(struct ahc_softc **)cmd->host->hostdata;

        /*
         * Save the callback on completion function.
         */
        cmd->scsi_done = scsi_done;

        ahc_lock(ahc, &flags);
        dev = ahc_linux_get_device(ahc, cmd->channel, cmd->target,
                                   cmd->lun, /*alloc*/TRUE);
        if (dev == NULL) {
                ahc_unlock(ahc, &flags);
                printf("aic7xxx_linux_queue: Unable to allocate device!\n");
                return (-ENOMEM);
        }
        cmd->result = CAM_REQ_INPROG << 16;
        TAILQ_INSERT_TAIL(&dev->busyq, (struct ahc_cmd *)cmd, acmd_links.tqe);
        if ((dev->flags & AHC_DEV_ON_RUN_LIST) == 0) {
                TAILQ_INSERT_TAIL(&ahc->platform_data->device_runq, dev, links);
                dev->flags |= AHC_DEV_ON_RUN_LIST;
                ahc_linux_run_device_queues(ahc);
        }
        ahc_unlock(ahc, &flags);
        return (0);
}

static void
ahc_linux_run_device_queue(struct ahc_softc *ahc, struct ahc_linux_device *dev)
{
        struct   ahc_cmd *acmd;
        struct   scsi_cmnd *cmd;
        struct   scb *scb;
        struct   hardware_scb *hscb;
        struct   ahc_initiator_tinfo *tinfo;
        struct   ahc_tmode_tstate *tstate;
        uint16_t mask;

        if ((dev->flags & AHC_DEV_ON_RUN_LIST) != 0)
                panic("running device on run list");

        while ((acmd = TAILQ_FIRST(&dev->busyq)) != NULL
            && dev->openings > 0 && dev->qfrozen == 0) {

                /*
                 * Schedule us to run later.  The only reason we are not
                 * running is because the whole controller Q is frozen.
                 */
                if (ahc->platform_data->qfrozen != 0) {

                        TAILQ_INSERT_TAIL(&ahc->platform_data->device_runq,
                                          dev, links);
                        dev->flags |= AHC_DEV_ON_RUN_LIST;
                        return;
                }
                /*
                 * Get an scb to use.
                 */
                if ((scb = ahc_get_scb(ahc)) == NULL) {
                        TAILQ_INSERT_TAIL(&ahc->platform_data->device_runq,
                                         dev, links);
                        dev->flags |= AHC_DEV_ON_RUN_LIST;
                        ahc->flags |= AHC_RESOURCE_SHORTAGE;
                        return;
                }
                TAILQ_REMOVE(&dev->busyq, acmd, acmd_links.tqe);
                cmd = &acmd_scsi_cmd(acmd);
                scb->io_ctx = cmd;
                scb->platform_data->dev = dev;
                hscb = scb->hscb;
                cmd->host_scribble = (char *)scb;

                /*
                 * Fill out basics of the HSCB.
                 */
                hscb->control = 0;
                hscb->scsiid = BUILD_SCSIID(ahc, cmd);
                hscb->lun = cmd->lun;
                mask = SCB_GET_TARGET_MASK(ahc, scb);
                tinfo = ahc_fetch_transinfo(ahc, SCB_GET_CHANNEL(ahc, scb),
                                            SCB_GET_OUR_ID(scb),
                                            SCB_GET_TARGET(ahc, scb), &tstate);
                hscb->scsirate = tinfo->scsirate;
                hscb->scsioffset = tinfo->curr.offset;
                if ((tstate->ultraenb & mask) != 0)
                        hscb->control |= ULTRAENB;

                if ((ahc->user_discenable & mask) != 0)
                        hscb->control |= DISCENB;

                if ((tstate->auto_negotiate & mask) != 0) {
                        scb->flags |= SCB_AUTO_NEGOTIATE;
                        scb->hscb->control |= MK_MESSAGE;
                }

                if ((dev->flags & (AHC_DEV_Q_TAGGED|AHC_DEV_Q_BASIC)) != 0) {
                        if (dev->commands_since_idle_or_otag == AHC_OTAG_THRESH
                         && (dev->flags & AHC_DEV_Q_TAGGED) != 0) {
                                hscb->control |= MSG_ORDERED_TASK;
                                dev->commands_since_idle_or_otag = 0;
                        } else {
                                hscb->control |= MSG_SIMPLE_TASK;
                        }
                }

                hscb->cdb_len = cmd->cmd_len;
                if (hscb->cdb_len <= 12) {
                        memcpy(hscb->shared_data.cdb, cmd->cmnd, hscb->cdb_len);
                } else {
                        memcpy(hscb->cdb32, cmd->cmnd, hscb->cdb_len);
                        scb->flags |= SCB_CDB32_PTR;
                }

                scb->platform_data->xfer_len = 0;
                ahc_set_residual(scb, 0);
                ahc_set_sense_residual(scb, 0);
                if (cmd->use_sg != 0) {
                        struct  ahc_dma_seg *sg;
                        struct  scatterlist *cur_seg;
                        struct  scatterlist *end_seg;
                        int     nseg;

                        cur_seg = (struct scatterlist *)cmd->request_buffer;
                        nseg = pci_map_sg(ahc->dev_softc, cur_seg, cmd->use_sg,
                                 scsi_to_pci_dma_dir(cmd ->sc_data_direction));
                        end_seg = cur_seg + nseg;
                        /* Copy the segments into the SG list. */
                        sg = scb->sg_list;
                        /*
                         * The sg_count may be larger than nseg if
                         * a transfer crosses a 32bit page.
                         */ 
                        scb->sg_count = 0;
                        while(cur_seg < end_seg) {
                                bus_addr_t addr;
                                bus_size_t len;
                                int consumed;

                                addr = sg_dma_address(cur_seg);
                                len = sg_dma_len(cur_seg);
                                consumed = ahc_linux_map_seg(ahc, scb,
                                                             sg, addr, len);
                                sg += consumed;
                                scb->sg_count += consumed;
                                cur_seg++;
                        }
                        sg--;
                        sg->len |= ahc_htole32(AHC_DMA_LAST_SEG);

                        /*
                         * Reset the sg list pointer.
                         */
                        scb->hscb->sgptr =
                            ahc_htole32(scb->sg_list_phys | SG_FULL_RESID);

                        /*
                         * Copy the first SG into the "current"
                         * data pointer area.
                         */
                        scb->hscb->dataptr = scb->sg_list->addr;
                        scb->hscb->datacnt = scb->sg_list->len;
                } else if (cmd->request_bufflen != 0) {
                        struct   ahc_dma_seg *sg;
                        bus_addr_t addr;

                        sg = scb->sg_list;
                        addr = pci_map_single(ahc->dev_softc,
                               cmd->request_buffer,
                               cmd->request_bufflen,
                               scsi_to_pci_dma_dir(cmd->sc_data_direction));
                        scb->sg_count = ahc_linux_map_seg(ahc, scb,
                                                          sg, addr,
                                                          cmd->request_bufflen);
                        sg->len |= ahc_htole32(AHC_DMA_LAST_SEG);

                        /*
                         * Reset the sg list pointer.
                         */
                        scb->hscb->sgptr =
                            ahc_htole32(scb->sg_list_phys | SG_FULL_RESID);

                        /*
                         * Copy the first SG into the "current"
                         * data pointer area.
                         */
                        scb->hscb->dataptr = sg->addr;
                        scb->hscb->datacnt = sg->len;
                } else {
                        scb->hscb->sgptr = ahc_htole32(SG_LIST_NULL);
                        scb->hscb->dataptr = 0;
                        scb->hscb->datacnt = 0;
                        scb->sg_count = 0;
                }

                ahc_sync_sglist(ahc, scb, BUS_DMASYNC_PREWRITE);
                LIST_INSERT_HEAD(&ahc->pending_scbs, scb, pending_links);
                dev->openings--;
                dev->active++;
                dev->commands_issued++;
                dev->commands_since_idle_or_otag++;

                /*
                 * We only allow one untagged transaction
                 * per target in the initiator role unless
                 * we are storing a full busy target *lun*
                 * table in SCB space.
                 */
                if ((scb->hscb->control & (TARGET_SCB|TAG_ENB)) == 0
                 && (ahc->features & AHC_SCB_BTT) == 0) {
                        struct scb_tailq *untagged_q;
                        int target_offset;

                        target_offset = SCB_GET_TARGET_OFFSET(ahc, scb);
                        untagged_q = &(ahc->untagged_queues[target_offset]);
                        TAILQ_INSERT_TAIL(untagged_q, scb, links.tqe);
                        scb->flags |= SCB_UNTAGGEDQ;
                        if (TAILQ_FIRST(untagged_q) != scb)
                                continue;
                }
                scb->flags |= SCB_ACTIVE;
                ahc_queue_scb(ahc, scb);
        }
}

/*
 * SCSI controller interrupt handler.
 */
void
ahc_linux_isr(int irq, void *dev_id, struct pt_regs * regs)
{
        struct ahc_softc *ahc;
        struct ahc_cmd *acmd;
        u_long flags;

        ahc = (struct ahc_softc *) dev_id;
        ahc_lock(ahc, &flags); 
        ahc_intr(ahc);
        /*
         * It would be nice to run the device queues from a
         * bottom half handler, but as there is no way to
         * dynamically register one, we'll have to postpone
         * that until we get integrated into the kernel.
         */
        ahc_linux_run_device_queues(ahc);
        acmd = TAILQ_FIRST(&ahc->platform_data->completeq);
        TAILQ_INIT(&ahc->platform_data->completeq);
        ahc_unlock(ahc, &flags);
        if (acmd != NULL)
                ahc_linux_run_complete_queue(ahc, acmd);
}

void
ahc_platform_flushwork(struct ahc_softc *ahc)
{
        struct ahc_cmd *acmd;

        acmd = TAILQ_FIRST(&ahc->platform_data->completeq);
        TAILQ_INIT(&ahc->platform_data->completeq);
        if (acmd != NULL)
                ahc_linux_run_complete_queue(ahc, acmd);
}

static struct ahc_linux_target*
ahc_linux_alloc_target(struct ahc_softc *ahc, u_int channel, u_int target)
{
        struct ahc_linux_target *targ;
        u_int target_offset;

        targ = malloc(sizeof(*targ), M_DEVBUG, M_NOWAIT);
        if (targ == NULL)
                return (NULL);
        memset(targ, 0, sizeof(*targ));
        targ->channel = channel;
        targ->target = target;
        target_offset = target;
        if (channel != 0)
                target_offset += 8;
        ahc->platform_data->targets[target_offset] = targ;
        return (targ);
}

static void
ahc_linux_free_target(struct ahc_softc *ahc, struct ahc_linux_target *targ)
{
        u_int target_offset;

        target_offset = targ->target;
        if (targ->channel != 0)
                target_offset += 8;
        ahc->platform_data->targets[target_offset] = NULL;
        free(targ, M_DEVBUF);
}

static struct ahc_linux_device*
ahc_linux_alloc_device(struct ahc_softc *ahc,
                 struct ahc_linux_target *targ, u_int lun)
{
        struct ahc_linux_device *dev;

        dev = malloc(sizeof(*dev), M_DEVBUG, M_NOWAIT);
        if (dev == NULL)
                return (NULL);
        memset(dev, 0, sizeof(*dev));
        TAILQ_INIT(&dev->busyq);
        dev->flags = AHC_DEV_UNCONFIGURED;
        dev->lun = lun;
        dev->target = targ;

        /*
         * We start out life using untagged
         * transactions of which we allow one.
         */
        dev->openings = 1;

        /*
         * Set maxtags to 0.  This will be changed if we
         * later determine that we are dealing with
         * a tagged queuing capable device.
         */
        dev->maxtags = 0;
        
        targ->refcount++;
        targ->devices[lun] = dev;
        return (dev);
}

static void
ahc_linux_free_device(struct ahc_softc *ahc, struct ahc_linux_device *dev)
{
        struct ahc_linux_target *targ;

        targ = dev->target;
        targ->devices[dev->lun] = NULL;
        free(dev, M_DEVBUF);
        targ->refcount--;
        if (targ->refcount == 0)
                ahc_linux_free_target(ahc, targ);
}

/*
 * Return a string describing the driver.
 */
const char *
ahc_linux_info(struct Scsi_Host *host)
{
        static char buffer[512];
        char    ahc_info[256];
        char   *bp;
        struct ahc_softc *ahc;

        bp = &buffer[0];
        ahc = *(struct ahc_softc **)host->hostdata;
        memset(bp, 0, sizeof(buffer));
        strcpy(bp, "Adaptec AIC7XXX EISA/VLB/PCI SCSI HBA DRIVER, Rev ");
        strcat(bp, AIC7XXX_DRIVER_VERSION);
        strcat(bp, "\n");
        strcat(bp, "        <");
        strcat(bp, ahc->description);
        strcat(bp, ">\n");
        strcat(bp, "        ");
        ahc_controller_info(ahc, ahc_info);
        strcat(bp, ahc_info);
        strcat(bp, "\n");

        return (bp);
}

void
ahc_send_async(struct ahc_softc *ahc, char channel,
               u_int target, u_int lun, ac_code code, void *arg)
{
        switch (code) {
        case AC_TRANSFER_NEG:
        {
                char    buf[80];
                struct  ahc_linux_target *targ;
                struct  info_str info;
                struct  ahc_initiator_tinfo *tinfo;
                struct  ahc_tmode_tstate *tstate;
                int     target_offset;

                info.buffer = buf;
                info.length = sizeof(buf);
                info.offset = 0;
                info.pos = 0;
                tinfo = ahc_fetch_transinfo(ahc, channel,
                                                channel == 'A' ? ahc->our_id
                                                               : ahc->our_id_b,
                                                target, &tstate);

                /*
                 * Don't bother reporting results while
                 * negotiations are still pending.
                 */
                if (tinfo->curr.period != tinfo->goal.period
                 || tinfo->curr.width != tinfo->goal.width
                 || tinfo->curr.offset != tinfo->goal.offset
                 || tinfo->curr.ppr_options != tinfo->goal.ppr_options)
                        if (bootverbose == 0)
                                break;

                /*
                 * Don't bother reporting results that
                 * are identical to those last reported.
                 */
                target_offset = target;
                if (channel == 'B')
                        target_offset += 8;
                targ = ahc->platform_data->targets[target_offset];
                if (targ != NULL
                 && tinfo->curr.period == targ->last_tinfo.period
                 && tinfo->curr.width == targ->last_tinfo.width
                 && tinfo->curr.offset == targ->last_tinfo.offset
                 && tinfo->curr.ppr_options == targ->last_tinfo.ppr_options)
                        if (bootverbose == 0)
                                break;

                targ->last_tinfo.period = tinfo->curr.period;
                targ->last_tinfo.width = tinfo->curr.width;
                targ->last_tinfo.offset = tinfo->curr.offset;
                targ->last_tinfo.ppr_options = tinfo->curr.ppr_options;

                printf("(%s:%c:", ahc_name(ahc), channel);
                if (target == CAM_TARGET_WILDCARD)
                        printf("*): ");
                else
                        printf("%d): ", target);
                ahc_format_transinfo(&info, &tinfo->curr);
                if (info.pos < info.length)
                        *info.buffer = '\0';
                else
                        buf[info.length - 1] = '\0';
                printf("%s", buf);
                break;
        }
        case AC_SENT_BDR:
                break;
        case AC_BUS_RESET:
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,3,0)
                if (ahc->platform_data->host != NULL) {
                        scsi_report_bus_reset(ahc->platform_data->host,
                                              channel - 'A');
                }
#endif
                break;
        default:
                panic("ahc_send_async: Unexpected async event");
        }
}

/*
 * Calls the higher level scsi done function and frees the scb.
 */
void
ahc_done(struct ahc_softc *ahc, struct scb * scb)
{
        Scsi_Cmnd *cmd;
        struct ahc_linux_device *dev;

        LIST_REMOVE(scb, pending_links);
        if ((scb->flags & SCB_UNTAGGEDQ) != 0) {
                struct scb_tailq *untagged_q;
                int target_offset;

                target_offset = SCB_GET_TARGET_OFFSET(ahc, scb);
                untagged_q = &(ahc->untagged_queues[target_offset]);
                TAILQ_REMOVE(untagged_q, scb, links.tqe);
                ahc_run_untagged_queue(ahc, untagged_q);
        }

        if ((scb->flags & SCB_ACTIVE) == 0) {
                printf("SCB %d done'd twice\n", scb->hscb->tag);
                ahc_dump_card_state(ahc);
                panic("Stopping for safety");
        }
        cmd = scb->io_ctx;
        dev = scb->platform_data->dev;
        dev->active--;
        dev->openings++;
        ahc_linux_unmap_scb(ahc, scb);
        if (scb->flags & SCB_SENSE) {
                memcpy(cmd->sense_buffer, ahc_get_sense_buf(ahc, scb),
                       MIN(sizeof(struct scsi_sense_data),
                           sizeof(cmd->sense_buffer)));
                cmd->result |= (DRIVER_SENSE << 24);
        } else {
                /*
                 * Guard against stale sense data.
                 * The Linux mid-layer assumes that sense
                 * was retrieved anytime the first byte of
                 * the sense buffer looks "sane".
                 */
                cmd->sense_buffer[0] = 0;
        }
        if (ahc_get_transaction_status(scb) == CAM_REQ_INPROG) {
                uint32_t amount_xferred;

                amount_xferred =
                    ahc_get_transfer_length(scb) - ahc_get_residual(scb);
                if (amount_xferred < scb->io_ctx->underflow) {
                        printf("Saw underflow (%ld of %ld bytes). "
                               "Treated as error\n",
                                ahc_get_residual(scb),
                                ahc_get_transfer_length(scb));
                        ahc_set_transaction_status(scb, CAM_DATA_RUN_ERR);
                } else {
                        ahc_set_transaction_status(scb, CAM_REQ_CMP);
                        ahc_linux_sniff_command(ahc, cmd, scb);
                }
        } else if (ahc_get_transaction_status(scb) == DID_OK) {
                ahc_linux_handle_scsi_status(ahc, dev, scb);
        } else if (ahc_get_transaction_status(scb) == DID_NO_CONNECT) {
                /*
                 * Should a selection timeout kill the device?
                 * That depends on whether the selection timeout
                 * is persistent.  Since we have no guarantee that
                 * the mid-layer will issue an inquiry for this device
                 * again, we can't just kill it off.
                dev->flags |= AHC_DEV_UNCONFIGURED;
                 */
        }

        if (dev->openings == 1
         && ahc_get_transaction_status(scb) == CAM_REQ_CMP
         && ahc_get_scsi_status(scb) != SCSI_STATUS_QUEUE_FULL)
                dev->tag_success_count++;
        /*
         * Some devices deal with temporary internal resource
         * shortages by returning queue full.  When the queue
         * full occurrs, we throttle back.  Slowly try to get
         * back to our previous queue depth.
         */
        if ((dev->openings + dev->active) < dev->maxtags
         && dev->tag_success_count > AHC_TAG_SUCCESS_INTERVAL) {
                dev->tag_success_count = 0;
                dev->openings++;
        }

        if (dev->active == 0)
                dev->commands_since_idle_or_otag = 0;

        if (TAILQ_EMPTY(&dev->busyq)) {
                if ((dev->flags & AHC_DEV_UNCONFIGURED) != 0
                 && dev->active == 0)
                        ahc_linux_free_device(ahc, dev);
        } else if ((dev->flags & AHC_DEV_ON_RUN_LIST) == 0) {
                TAILQ_INSERT_TAIL(&ahc->platform_data->device_runq, dev, links);
                dev->flags |= AHC_DEV_ON_RUN_LIST;
        }

        if ((scb->flags & SCB_RECOVERY_SCB) != 0) {
                printf("Recovery SCB completes\n");
                up(&ahc->platform_data->eh_sem);
        }

        ahc_free_scb(ahc, scb);
        ahc_linux_queue_cmd_complete(ahc, cmd);
}

static void
ahc_linux_handle_scsi_status(struct ahc_softc *ahc,
                             struct ahc_linux_device *dev, struct scb *scb)
{
        /*
         * We don't currently trust the mid-layer to
         * properly deal with queue full or busy.  So,
         * when one occurs, we tell the mid-layer to
         * unconditionally requeue the command to us
         * so that we can retry it ourselves.  We also
         * implement our own throttling mechanism so
         * we don't clobber the device with too many
         * commands.
         */
        switch (ahc_get_scsi_status(scb)) {
        default:
                break;
        case SCSI_STATUS_QUEUE_FULL:
        {
                /*
                 * By the time the core driver has returned this
                 * command, all other commands that were queued
                 * to us but not the device have been returned.
                 * This ensures that dev->active is equal to
                 * the number of commands actually queued to
                 * the device.
                 */
                dev->tag_success_count = 0;
                if (dev->active != 0) {
                        /*
                         * Drop our opening count to the number
                         * of commands currently outstanding.
                         */
                        dev->openings = 0;
/*
                        ahc_print_path(ahc, scb);
                        printf("Dropping tag count to %d\n", dev->active);
 */
                        if (dev->active == dev->tags_on_last_queuefull) {

                                dev->last_queuefull_same_count++;
                                /*
                                 * If we repeatedly see a queue full
                                 * at the same queue depth, this
                                 * device has a fixed number of tag
                                 * slots.  Lock in this tag depth
                                 * so we stop seeing queue fulls from
                                 * this device.
                                 */
                                if (dev->last_queuefull_same_count
                                 == AHC_LOCK_TAGS_COUNT) {
                                        dev->maxtags = dev->active;
                                        ahc_print_path(ahc, scb);
                                        printf("Locking max tag count at %d\n",
                                               dev->active);
                                }
                        } else {
                                dev->tags_on_last_queuefull = dev->active;
                                dev->last_queuefull_same_count = 0;
                        }
                        ahc_set_transaction_status(scb, CAM_REQUEUE_REQ);
                        ahc_set_scsi_status(scb, SCSI_STATUS_OK);
                        break;
                }
                /*
                 * Drop down to a single opening, and treat this
                 * as if the target return BUSY SCSI status.
                 */
                dev->openings = 1;
                /* FALLTHROUGH */
        }
        case SCSI_STATUS_BUSY:
                /*
                 * XXX Set a timer and handle ourselves????
                 * For now we pray that the mid-layer does something
                 * sane for devices that are busy.
                 */
                ahc_set_scsi_status(scb, SCSI_STATUS_BUSY);
                break;
        }
}

static void
ahc_linux_filter_command(struct ahc_softc *ahc, Scsi_Cmnd *cmd, struct scb *scb)
{
        switch (cmd->cmnd[0]) {
        case INQUIRY:
        {
                struct  ahc_devinfo devinfo;
                struct  scsi_inquiry *inq;
                struct  scsi_inquiry_data *sid;
                struct  ahc_initiator_tinfo *targ_info;
                struct  ahc_tmode_tstate *tstate;
                struct  ahc_syncrate *syncrate;
                struct  ahc_linux_device *dev;
                u_int   scsiid;
                u_int   maxsync;
                int     transferred_len;
                int     minlen;
                u_int   width;
                u_int   period;
                u_int   offset;
                u_int   ppr_options;

                 /*
                  * Validate the command.  We only want to filter
                  * standard inquiry commands, not those querying
                  * Vital Product Data.
                  */
                inq = (struct scsi_inquiry *)cmd->cmnd;
                if ((inq->byte2 & SI_EVPD) != 0
                 || inq->page_code != 0)
                        break;

                if (cmd->use_sg != 0) {
                        printf("%s: SG Inquiry response ignored\n",
                               ahc_name(ahc));
                        break;
                }
                transferred_len = ahc_get_transfer_length(scb)
                                - ahc_get_residual(scb);
                sid = (struct scsi_inquiry_data *)cmd->request_buffer;

                /*
                 * Determine if this lun actually exists.  If so,
                 * hold on to its corresponding device structure.
                 * If not, make sure we release the device and
                 * don't bother processing the rest of this inquiry
                 * command.
                 */
                dev = ahc_linux_get_device(ahc, cmd->channel,
                                           cmd->target, cmd->lun,
                                           /*alloc*/FALSE);
                if (transferred_len >= 1
                 && SID_QUAL(sid) == SID_QUAL_LU_CONNECTED) {

                        dev->flags &= ~AHC_DEV_UNCONFIGURED;
                } else {
                        dev->flags |= AHC_DEV_UNCONFIGURED;
                        break;
                }

                /*
                 * Update our notion of this device's transfer
                 * negotiation capabilities.
                 */
                scsiid = BUILD_SCSIID(ahc, cmd);
                ahc_compile_devinfo(&devinfo, SCSIID_OUR_ID(scsiid),
                                    cmd->target, cmd->lun,
                                    SCSIID_CHANNEL(ahc, scsiid),
                                    ROLE_INITIATOR);
                targ_info = ahc_fetch_transinfo(ahc, devinfo.channel,
                                                devinfo.our_scsiid,
                                                devinfo.target, &tstate);
                width = targ_info->user.width;
                period = targ_info->user.period;
                offset = targ_info->user.offset;
                ppr_options = targ_info->user.ppr_options;
                minlen = offsetof(struct scsi_inquiry_data, version) + 1;
                if (transferred_len >= minlen) {
                        targ_info->curr.protocol_version = SID_ANSI_REV(sid);

                        /*
                         * Only attempt SPI3 once we've verified that
                         * the device claims to support SPI3 features.
                         */
                        if (targ_info->curr.protocol_version < SCSI_REV_2)
                                targ_info->curr.transport_version =
                                    SID_ANSI_REV(sid);
                        else
                                targ_info->curr.transport_version =
                                     SCSI_REV_2;
                }

                minlen = offsetof(struct scsi_inquiry_data, flags) + 1;
                if (transferred_len >= minlen
                 && (sid->additional_length + 4) >= minlen) {
                        if ((sid->flags & SID_WBus16) == 0)
                                width = MSG_EXT_WDTR_BUS_8_BIT;
                        if ((sid->flags & SID_Sync) == 0) {
                                period = 0;
                                offset = 0;
                                ppr_options = 0;
                        }
                } else {
                        /* Keep current settings */
                        break;
                }
                minlen = offsetof(struct scsi_inquiry_data, spi3data) + 1;
                /*
                 * This is a kludge to deal with inquiry requests that
                 * are not large enough for us to pull the spi3 bits.
                 * In this case, we assume that a device that tells us
                 * they can provide inquiry data that spans the SPI3
                 * bits can handle a PPR request.  If the inquiry
                 * request has sufficient buffer space to cover these
                 * bits, we check them to see if any ppr options are
                 * available.
                 */
                if ((sid->additional_length + 4) >= minlen) {
                        if (transferred_len >= minlen
                         && (sid->spi3data & SID_SPI_CLOCK_DT) == 0)
                                ppr_options = 0;

                        if (targ_info->curr.protocol_version > SCSI_REV_2)
                                targ_info->curr.transport_version = 3;
                } else {
                        ppr_options = 0;
                }
                ahc_validate_width(ahc, /*tinfo limit*/NULL, &width,
                                   ROLE_UNKNOWN);
                if ((ahc->features & AHC_ULTRA2) != 0)
                        maxsync = AHC_SYNCRATE_DT;
                else if ((ahc->features & AHC_ULTRA) != 0)
                        maxsync = AHC_SYNCRATE_ULTRA;
                else
                        maxsync = AHC_SYNCRATE_FAST;

                syncrate = ahc_find_syncrate(ahc, &period,
                                             &ppr_options, maxsync);
                ahc_validate_offset(ahc, /*tinfo limit*/NULL, syncrate,
                                    &offset, width, ROLE_UNKNOWN);
                if (offset == 0 || period == 0) {
                        period = 0;
                        offset = 0;
                        ppr_options = 0;
                }
                /* Apply our filtered user settings. */
                ahc_set_width(ahc, &devinfo, width,
                              AHC_TRANS_GOAL, /*paused*/FALSE);
                ahc_set_syncrate(ahc, &devinfo, syncrate, period,
                                 offset, ppr_options, AHC_TRANS_GOAL,
                                 /*paused*/FALSE);
                break;
        }
        default:
                panic("ahc_linux_filter_command: Unexpected Command type  %x\n",
                      cmd->cmnd[0]);
                break;
        }
}

static void
ahc_linux_sem_timeout(u_long arg)
{
        struct semaphore *sem;

        sem = (struct semaphore *)arg;
        up(sem);
}

static void
ahc_linux_freeze_sim_queue(struct ahc_softc *ahc)
{
        ahc->platform_data->qfrozen++;
        if (ahc->platform_data->qfrozen == 1)
                scsi_block_requests(ahc->platform_data->host);
}

static void
ahc_linux_release_sim_queue(u_long arg)
{
        struct ahc_softc *ahc;
        u_long s;
        int    unblock_reqs;

        ahc = (struct ahc_softc *)arg;
        unblock_reqs = 0;
        ahc_lock(ahc, &s);
        if (ahc->platform_data->qfrozen > 0)
                ahc->platform_data->qfrozen--;
        if (ahc->platform_data->qfrozen == 0) {
                unblock_reqs = 1;
                ahc_linux_run_device_queues(ahc);
        }
        ahc_unlock(ahc, &s);
        /*
         * There is still a race here.  The mid-layer
         * should keep its own freeze count and use
         * a bottom half handler to run the queues
         * so we can unblock with our own lock held.
         */
        if (unblock_reqs)
                scsi_unblock_requests(ahc->platform_data->host);
}

static int
ahc_linux_queue_recovery_cmd(Scsi_Cmnd *cmd, scb_flag flag)
{
        struct ahc_softc *ahc;
        struct ahc_cmd *acmd;
        struct ahc_cmd *list_acmd;
        struct ahc_linux_device *dev;
        struct scb *pending_scb;
        u_long s;
        u_int  saved_scbptr;
        u_int  active_scb_index;
        u_int  last_phase;
        int    retval;
        int    paused;
        int    wait;
        int    disconnected;

        paused = FALSE;
        wait = FALSE;
        ahc = *(struct ahc_softc **)cmd->host->hostdata;
        acmd = (struct ahc_cmd *)cmd;

        printf("%s:%d:%d:%d: Attempting to queue a%s message\n",
               ahc_name(ahc), cmd->channel, cmd->target, cmd->lun,
               flag == SCB_ABORT ? "n ABORT" : " TARGET RESET");

        /*
         * It is a bug that the upper layer takes
         * this lock just prior to calling us.
         */
        spin_unlock_irq(&io_request_lock);

        ahc_lock(ahc, &s);

        /*
         * First determine if we currently own this command.
         * Start by searching the device queue.  If not found
         * there, check the pending_scb list.  If not found
         * at all, and the system wanted us to just abort the
         * command return success.
         */
        dev = ahc_linux_get_device(ahc, cmd->channel, cmd->target,
                                   cmd->lun, /*alloc*/FALSE);

        if (dev == NULL) {
                /*
                 * No target device for this command exists,
                 * so we must not still own the command.
                 */
                printf("%s:%d:%d:%d: Is not an active device\n",
                       ahc_name(ahc), cmd->channel, cmd->target, cmd->lun);
                retval = SUCCESS;
                goto no_cmd;
        }

        TAILQ_FOREACH(list_acmd, &dev->busyq, acmd_links.tqe) {
                if (list_acmd == acmd)
                        break;
        }

        if (list_acmd != NULL) {
                printf("%s:%d:%d:%d: Command found on device queue\n",
                       ahc_name(ahc), cmd->channel, cmd->target, cmd->lun);
                if (flag == SCB_ABORT) {
                        TAILQ_REMOVE(&dev->busyq, list_acmd, acmd_links.tqe);
                        cmd->result = DID_ABORT << 16;
                        ahc_linux_queue_cmd_complete(ahc, cmd);
                        retval = SUCCESS;
                        goto done;
                }
        }

        /*
         * See if we can find a matching cmd in the pending list.
         */
        LIST_FOREACH(pending_scb, &ahc->pending_scbs, pending_links) {
                if (pending_scb->io_ctx == cmd)
                        break;
        }

        if (pending_scb == NULL && flag == SCB_DEVICE_RESET) {

                /* Any SCB for this device will do for a target reset */
                LIST_FOREACH(pending_scb, &ahc->pending_scbs, pending_links) {
                        if (ahc_match_scb(ahc, pending_scb, cmd->target,
                                          cmd->channel, CAM_LUN_WILDCARD,
                                          SCB_LIST_NULL, ROLE_INITIATOR) == 0)
                                break;
                }
        }

        if (pending_scb == NULL) {
                printf("%s:%d:%d:%d: Command not found\n",
                       ahc_name(ahc), cmd->channel, cmd->target, cmd->lun);
                goto no_cmd;
        }

        if ((pending_scb->flags & SCB_RECOVERY_SCB) != 0) {
                /*
                 * We can't queue two recovery actions using the same SCB
                 */
                retval = FAILED;
                goto  done;
        }

        /*
         * Ensure that the card doesn't do anything
         * behind our back.  Also make sure that we
         * didn't "just" miss an interrupt that would
         * affect this cmd.
         */
        ahc->flags |= AHC_ALL_INTERRUPTS;
        do {
                ahc_intr(ahc);
                ahc_pause(ahc);
                ahc_clear_critical_section(ahc);
        } while (ahc_inb(ahc, INTSTAT) & INT_PEND);
        ahc->flags &= ~AHC_ALL_INTERRUPTS;
        paused = TRUE;

        if (bootverbose)
                ahc_dump_card_state(ahc);

        if ((pending_scb->flags & SCB_ACTIVE) == 0) {
                printf("%s:%d:%d:%d: Command already completed\n",
                       ahc_name(ahc), cmd->channel, cmd->target, cmd->lun);
                goto no_cmd;
        }

        disconnected = TRUE;
        if (flag == SCB_ABORT) {
                if (ahc_search_qinfifo(ahc, cmd->target, cmd->channel + 'A',
                                       cmd->lun, pending_scb->hscb->tag,
                                       ROLE_INITIATOR, CAM_REQ_ABORTED,
                                       SEARCH_COMPLETE) > 0) {
                        printf("%s:%d:%d:%d: Cmd aborted from QINFIFO\n",
                               ahc_name(ahc), cmd->channel, cmd->target,
                                        cmd->lun);
                        retval = SUCCESS;
                        goto done;
                }
        } else if (ahc_search_qinfifo(ahc, cmd->target, cmd->channel + 'A',
                                      cmd->lun, pending_scb->hscb->tag,
                                      ROLE_INITIATOR, /*status*/0,
                                      SEARCH_COUNT) > 0) {
                disconnected = FALSE;
        }

        /*
         * At this point, pending_scb is the scb associated with the
         * passed in command.  That command is currently active on the
         * bus, is in the disconnected state, or we're hoping to find
         * a command for the same target active on the bus to abuse to
         * send a BDR.  Queue the appropriate message based on which of
         * these states we are in.
         */
        last_phase = ahc_inb(ahc, LASTPHASE);
        saved_scbptr = ahc_inb(ahc, SCBPTR);
        active_scb_index = ahc_inb(ahc, SCB_TAG);
        if (last_phase != P_BUSFREE
         && (pending_scb->hscb->tag == active_scb_index
          || (flag == SCB_DEVICE_RESET
           && SCSIID_TARGET(ahc, ahc_inb(ahc, SAVED_SCSIID)) == cmd->target))) {

                /*
                 * We're active on the bus, so assert ATN
                 * and hope that the target responds.
                 */
                pending_scb = ahc_lookup_scb(ahc, active_scb_index);
                pending_scb->flags |= SCB_RECOVERY_SCB|flag;
                ahc_outb(ahc, MSG_OUT, HOST_MSG);
                ahc_outb(ahc, SCSISIGO, last_phase|ATNO);
                printf("%s:%d:%d:%d: Device is active, asserting ATN\n",
                       ahc_name(ahc), cmd->channel, cmd->target, cmd->lun);
                wait = TRUE;
        } else if (disconnected) {

                /*
                 * Actually re-queue this SCB in an attempt
                 * to select the device before it reconnects.
                 * In either case (selection or reselection),
                 * we will now issue a the approprate message
                 * to the timed-out device.
                 *
                 * Set the MK_MESSAGE control bit indicating
                 * that we desire to send a message.  We
                 * also set the disconnected flag since
                 * in the paging case there is no guarantee
                 * that our SCB control byte matches the
                 * version on the card.  We don't want the
                 * sequencer to abort the command thinking
                 * an unsolicited reselection occurred.
                 */
                pending_scb->hscb->control |= MK_MESSAGE|DISCONNECTED;
                pending_scb->flags |= SCB_RECOVERY_SCB|flag;

                /*
                 * Remove any cached copy of this SCB in the
                 * disconnected list in preparation for the
                 * queuing of our abort SCB.  We use the
                 * same element in the SCB, SCB_NEXT, for
                 * both the qinfifo and the disconnected list.
                 */
                ahc_search_disc_list(ahc, cmd->target, cmd->channel + 'A',
                                     cmd->lun, pending_scb->hscb->tag,
                                     /*stop_on_first*/TRUE,
                                     /*remove*/TRUE,
                                     /*save_state*/FALSE);

                /*
                 * In the non-paging case, the sequencer will
                 * never re-reference the in-core SCB.
                 * To make sure we are notified during
                 * reslection, set the MK_MESSAGE flag in
                 * the card's copy of the SCB.
                 */
                if ((ahc->flags & AHC_PAGESCBS) == 0) {
                        ahc_outb(ahc, SCBPTR, pending_scb->hscb->tag);
                        ahc_outb(ahc, SCB_CONTROL,
                                 ahc_inb(ahc, SCB_CONTROL)|MK_MESSAGE);
                }

                /*
                 * Clear out any entries in the QINFIFO first
                 * so we are the next SCB for this target
                 * to run.
                 */
                ahc_search_qinfifo(ahc, cmd->target, cmd->channel + 'A',
                                   cmd->lun, SCB_LIST_NULL, ROLE_INITIATOR,
                                   CAM_REQUEUE_REQ, SEARCH_COMPLETE);
                ahc_print_path(ahc, pending_scb);
                printf("Queuing a recovery SCB\n");
                ahc_qinfifo_requeue_tail(ahc, pending_scb);
                ahc_outb(ahc, SCBPTR, saved_scbptr);
                printf("%s:%d:%d:%d: Device is disconnected, re-queuing SCB\n",
                       ahc_name(ahc), cmd->channel, cmd->target, cmd->lun);
                wait = TRUE;
        } else {
                printf("%s:%d:%d:%d: Unable to deliver message\n",
                       ahc_name(ahc), cmd->channel, cmd->target, cmd->lun);
                retval = FAILED;
                goto done;
        }

no_cmd:
        /*
         * Our assumption is that if we don't have the command, no
         * recovery action was required, so we return success.  Again,
         * the semantics of the mid-layer recovery engine are not
         * well defined, so this may change in time.
         */
        retval = SUCCESS;
done:
        if (paused)
                ahc_unpause(ahc);
        if (wait) {
                struct timer_list timer;
                int ret;

                ahc_unlock(ahc, &s);
                init_timer(&timer);
                timer.data = (u_long)&ahc->platform_data->eh_sem;
                timer.expires = jiffies + (5 * HZ);
                timer.function = ahc_linux_sem_timeout;
                add_timer(&timer);
                printf("Recovery code sleeping\n");
                down(&ahc->platform_data->eh_sem);
                printf("Recovery code awake\n");
                ret = del_timer(&timer);
                if (ret == 0) {
                        printf("Timer Expired\n");
                        retval = FAILED;
                }
                ahc_lock(ahc, &s);
        }
        ahc_linux_run_device_queues(ahc);
        acmd = TAILQ_FIRST(&ahc->platform_data->completeq);
        TAILQ_INIT(&ahc->platform_data->completeq);
        ahc_unlock(ahc, &s);
        if (acmd != NULL)
                ahc_linux_run_complete_queue(ahc, acmd);
        spin_lock_irq(&io_request_lock);
        return (retval);
}

/*
 * Abort the current SCSI command(s).
 */
int
ahc_linux_abort(Scsi_Cmnd *cmd)
{
        int error;

        error = ahc_linux_queue_recovery_cmd(cmd, SCB_ABORT);
        if (error != 0)
                printf("aic7xxx_abort returns %d\n", error);
        return (error);
}

/*
 * Attempt to send a target reset message to the device that timed out.
 */
int
ahc_linux_dev_reset(Scsi_Cmnd *cmd)
{
        int error;

        error = ahc_linux_queue_recovery_cmd(cmd, SCB_DEVICE_RESET);
        if (error != 0)
                printf("aic7xxx_dev_reset returns %d\n", error);
        return (error);
}

/*
 * Reset the SCSI bus.
 */
int
ahc_linux_bus_reset(Scsi_Cmnd *cmd)
{
        struct ahc_softc *ahc;
        struct ahc_cmd *acmd;
        u_long s;
        int    found;

        /*
         * It is a bug that the upper layer takes
         * this lock just prior to calling us.
         */
        spin_unlock_irq(&io_request_lock);

        ahc = *(struct ahc_softc **)cmd->host->hostdata;
        ahc_lock(ahc, &s);
        found = ahc_reset_channel(ahc, cmd->channel + 'A',
                                  /*initiate reset*/TRUE);
        acmd = TAILQ_FIRST(&ahc->platform_data->completeq);
        TAILQ_INIT(&ahc->platform_data->completeq);
        ahc_unlock(ahc, &s);
        if (bootverbose)
                printf("%s: SCSI bus reset delivered. "
                       "%d SCBs aborted.\n", ahc_name(ahc), found);

        if (acmd != NULL)
                ahc_linux_run_complete_queue(ahc, acmd);

        spin_lock_irq(&io_request_lock);
        return SUCCESS;
}

/*
 * Return the disk geometry for the given SCSI device.
 */
int
ahc_linux_biosparam(Disk *disk, kdev_t dev, int geom[])
{
        int     heads;
        int     sectors;
        int     cylinders;
        int     ret;
        int     extended;
        struct  ahc_softc *ahc;
        struct  buffer_head *bh;

        ahc = *((struct ahc_softc **)disk->device->host->hostdata);
        bh = bread(MKDEV(MAJOR(dev), MINOR(dev) & ~0xf), 0, 1024);

        if (bh) {
                ret = scsi_partsize(bh, disk->capacity,
                                    &geom[2], &geom[0], &geom[1]);
                brelse(bh);
                if (ret != -1)
                        return (ret);
        }
        heads = 64;
        sectors = 32;
        cylinders = disk->capacity / (heads * sectors);

        if (disk->device->channel == 0)
                extended = (ahc->flags & AHC_EXTENDED_TRANS_A) != 0;
        else
                extended = (ahc->flags & AHC_EXTENDED_TRANS_B) != 0;
        if (extended && cylinders >= 1024) {
                heads = 255;
                sectors = 63;
                cylinders = disk->capacity / (heads * sectors);
        }
        geom[0] = heads;
        geom[1] = sectors;
        geom[2] = cylinders;
        return (0);
}

/*
 * Free the passed in Scsi_Host memory structures prior to unloading the
 * module.
 */
int
ahc_linux_release(struct Scsi_Host * host)
{
        struct ahc_softc *ahc;

        if (host != NULL) {

                ahc = *(struct ahc_softc **)host->hostdata;
                ahc_free(ahc);
        }
        if (TAILQ_EMPTY(&ahc_tailq)) {
                unregister_reboot_notifier(&ahc_linux_notifier);
#ifdef CONFIG_PCI
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,4,0)
                pci_unregister_driver(&aic7xxx_pci_driver);
#endif
#endif
        }
        return (0);
}

void
ahc_platform_dump_card_state(struct ahc_softc *ahc)
{
        struct ahc_linux_device *dev;
        int channel;
        int maxchannel;
        int target;
        int maxtarget;
        int lun;
        int i;

        maxchannel = (ahc->features & AHC_TWIN) ? 1 : 0;
        maxtarget = (ahc->features & AHC_WIDE) ? 15 : 7;
        for (channel = 0; channel <= maxchannel; channel++) {
                for (target = 0; target <=maxtarget; target++) {
                        for (lun = 0; lun < AHC_NUM_LUNS; lun++) {
                                struct ahc_cmd *acmd;

                                dev = ahc_linux_get_device(ahc, channel, target,
                                                           lun, /*alloc*/FALSE);
                                if (dev == NULL)
                                        continue;

                                printf("DevQ(%d:%d:%d): ",
                                       channel, target, lun);
                                i = 0;
                                TAILQ_FOREACH(acmd, &dev->busyq,
                                              acmd_links.tqe) {
                                        if (i++ > 256)
                                                break;
                                }
                                printf("%d waiting\n", i);
                        }
                }
        }
}

MODULE_LICENSE("Dual BSD/GPL");

#if defined(MODULE) || LINUX_VERSION_CODE >= KERNEL_VERSION(2,4,0)
static Scsi_Host_Template driver_template = AIC7XXX;
Scsi_Host_Template *aic7xxx_driver_template = &driver_template;
#include "../scsi_module.c"
#endif