/*
   3w-9xxx.c -- 3ware 9000 Storage Controller device driver for Linux.

   Written By: Adam Radford <linuxraid@amcc.com>

   Copyright (C) 2004-2005 Applied Micro Circuits Corporation.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; version 2 of the License.

   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.

   NO WARRANTY
   THE PROGRAM IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OR
   CONDITIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED INCLUDING, WITHOUT
   LIMITATION, ANY WARRANTIES OR CONDITIONS OF TITLE, NON-INFRINGEMENT,
   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Each Recipient is
   solely responsible for determining the appropriateness of using and
   distributing the Program and assumes all risks associated with its
   exercise of rights under this Agreement, including but not limited to
   the risks and costs of program errors, damage to or loss of data,
   programs or equipment, and unavailability or interruption of operations.

   DISCLAIMER OF LIABILITY
   NEITHER RECIPIENT NOR ANY CONTRIBUTORS SHALL HAVE ANY LIABILITY FOR ANY
   DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   DAMAGES (INCLUDING WITHOUT LIMITATION LOST PROFITS), 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 OR DISTRIBUTION OF THE PROGRAM OR THE EXERCISE OF ANY RIGHTS GRANTED
   HEREUNDER, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGES

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

   Bugs/Comments/Suggestions should be mailed to:
   linuxraid@amcc.com

   For more information, goto:
   http://www.amcc.com

   Note: This version of the driver does not contain a bundled firmware
         image.

   History
   -------
   2.26.02.000 - Driver cleanup for kernel submission.
   2.26.02.001 - Replace schedule_timeout() calls with msleep().
   2.26.02.002 - Add support for PAE mode.
                 Add lun support.
                 Fix twa_remove() to free irq handler/unregister_chrdev()
                 before shutting down card.
                 Change to new 'change_queue_depth' api.
                 Fix 'handled=1' ISR usage, remove bogus IRQ check.
                 Remove un-needed eh_abort handler.
                 Add support for embedded firmware error strings.
*/

#include <linux/module.h>
#include <linux/reboot.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>
#include <linux/moduleparam.h>
#include <linux/errno.h>
#include <linux/types.h>
#include <linux/delay.h>
#include <linux/pci.h>
#include <linux/time.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/uaccess.h>
#include <scsi/scsi.h>
#include <scsi/scsi_host.h>
#include <scsi/scsi_tcq.h>
#include <scsi/scsi_cmnd.h>
#include "3w-9xxx.h"

/* Globals */
#define TW_DRIVER_VERSION "2.26.02.002"
static TW_Device_Extension *twa_device_extension_list[TW_MAX_SLOT];
static unsigned int twa_device_extension_count;
static int twa_major = -1;
extern struct timezone sys_tz;

/* Module parameters */
MODULE_AUTHOR ("AMCC");
MODULE_DESCRIPTION ("3ware 9000 Storage Controller Linux Driver");
MODULE_LICENSE("GPL");
MODULE_VERSION(TW_DRIVER_VERSION);

/* Function prototypes */
static void twa_aen_queue_event(TW_Device_Extension *tw_dev, TW_Command_Apache_Header *header);
static int twa_aen_read_queue(TW_Device_Extension *tw_dev, int request_id);
static char *twa_aen_severity_lookup(unsigned char severity_code);
static void twa_aen_sync_time(TW_Device_Extension *tw_dev, int request_id);
static int twa_chrdev_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg);
static int twa_chrdev_open(struct inode *inode, struct file *file);
static int twa_fill_sense(TW_Device_Extension *tw_dev, int request_id, int copy_sense, int print_host);
static void twa_free_request_id(TW_Device_Extension *tw_dev,int request_id);
static void twa_get_request_id(TW_Device_Extension *tw_dev, int *request_id);
static int twa_initconnection(TW_Device_Extension *tw_dev, int message_credits,
 			      u32 set_features, unsigned short current_fw_srl, 
			      unsigned short current_fw_arch_id, 
			      unsigned short current_fw_branch, 
			      unsigned short current_fw_build, 
			      unsigned short *fw_on_ctlr_srl, 
			      unsigned short *fw_on_ctlr_arch_id, 
			      unsigned short *fw_on_ctlr_branch, 
			      unsigned short *fw_on_ctlr_build, 
			      u32 *init_connect_result);
static void twa_load_sgl(TW_Command_Full *full_command_packet, int request_id, dma_addr_t dma_handle, int length);
static int twa_poll_response(TW_Device_Extension *tw_dev, int request_id, int seconds);
static int twa_poll_status_gone(TW_Device_Extension *tw_dev, u32 flag, int seconds);
static int twa_post_command_packet(TW_Device_Extension *tw_dev, int request_id, char internal);
static int twa_reset_device_extension(TW_Device_Extension *tw_dev, int ioctl_reset);
static int twa_reset_sequence(TW_Device_Extension *tw_dev, int soft_reset);
static int twa_scsiop_execute_scsi(TW_Device_Extension *tw_dev, int request_id, char *cdb, int use_sg, TW_SG_Entry *sglistarg);
static void twa_scsiop_execute_scsi_complete(TW_Device_Extension *tw_dev, int request_id);
static char *twa_string_lookup(twa_message_type *table, unsigned int aen_code);
static void twa_unmap_scsi_data(TW_Device_Extension *tw_dev, int request_id);

/* Functions */

/* Show some statistics about the card */
static ssize_t twa_show_stats(struct class_device *class_dev, char *buf)
{
	struct Scsi_Host *host = class_to_shost(class_dev);
	TW_Device_Extension *tw_dev = (TW_Device_Extension *)host->hostdata;
	unsigned long flags = 0;
	ssize_t len;

	spin_lock_irqsave(tw_dev->host->host_lock, flags);
	len = snprintf(buf, PAGE_SIZE, "3w-9xxx Driver version: %s\n"
		       "Current commands posted:   %4d\n"
		       "Max commands posted:       %4d\n"
		       "Current pending commands:  %4d\n"
		       "Max pending commands:      %4d\n"
		       "Last sgl length:           %4d\n"
		       "Max sgl length:            %4d\n"
		       "Last sector count:         %4d\n"
		       "Max sector count:          %4d\n"
		       "SCSI Host Resets:          %4d\n"
		       "AEN's:                     %4d\n", 
		       TW_DRIVER_VERSION,
		       tw_dev->posted_request_count,
		       tw_dev->max_posted_request_count,
		       tw_dev->pending_request_count,
		       tw_dev->max_pending_request_count,
		       tw_dev->sgl_entries,
		       tw_dev->max_sgl_entries,
		       tw_dev->sector_count,
		       tw_dev->max_sector_count,
		       tw_dev->num_resets,
		       tw_dev->aen_count);
	spin_unlock_irqrestore(tw_dev->host->host_lock, flags);
	return len;
} /* End twa_show_stats() */

/* This function will set a devices queue depth */
static int twa_change_queue_depth(struct scsi_device *sdev, int queue_depth)
{
	if (queue_depth > TW_Q_LENGTH-2)
		queue_depth = TW_Q_LENGTH-2;
	scsi_adjust_queue_depth(sdev, MSG_ORDERED_TAG, queue_depth);
	return queue_depth;
} /* End twa_change_queue_depth() */

/* Create sysfs 'stats' entry */
static struct class_device_attribute twa_host_stats_attr = {
	.attr = {
		.name = 	"stats",
		.mode =		S_IRUGO,
	},
	.show = twa_show_stats
};

/* Host attributes initializer */
static struct class_device_attribute *twa_host_attrs[] = {
	&twa_host_stats_attr,
	NULL,
};

/* File operations struct for character device */
static struct file_operations twa_fops = {
	.owner		= THIS_MODULE,
	.ioctl		= twa_chrdev_ioctl,
	.open		= twa_chrdev_open,
	.release	= NULL
};

/* This function will complete an aen request from the isr */
static int twa_aen_complete(TW_Device_Extension *tw_dev, int request_id)
{
	TW_Command_Full *full_command_packet;
	TW_Command *command_packet;
	TW_Command_Apache_Header *header;
	unsigned short aen;
	int retval = 1;

	header = (TW_Command_Apache_Header *)tw_dev->generic_buffer_virt[request_id];
	tw_dev->posted_request_count--;
	aen = header->status_block.error;
	full_command_packet = tw_dev->command_packet_virt[request_id];
	command_packet = &full_command_packet->command.oldcommand;

	/* First check for internal completion of set param for time sync */
	if (TW_OP_OUT(command_packet->opcode__sgloffset) == TW_OP_SET_PARAM) {
		/* Keep reading the queue in case there are more aen's */
		if (twa_aen_read_queue(tw_dev, request_id))
			goto out2;
	        else {
			retval = 0;
			goto out;
		}
	}

	switch (aen) {
	case TW_AEN_QUEUE_EMPTY:
		/* Quit reading the queue if this is the last one */
		break;
	case TW_AEN_SYNC_TIME_WITH_HOST:
		twa_aen_sync_time(tw_dev, request_id);
		retval = 0;
		goto out;
	default:
		twa_aen_queue_event(tw_dev, header);

		/* If there are more aen's, keep reading the queue */
		if (twa_aen_read_queue(tw_dev, request_id))
			goto out2;
		else {
			retval = 0;
			goto out;
		}
	}
	retval = 0;
out2:
	tw_dev->state[request_id] = TW_S_COMPLETED;
	twa_free_request_id(tw_dev, request_id);
	clear_bit(TW_IN_ATTENTION_LOOP, &tw_dev->flags);
out:
	return retval;
} /* End twa_aen_complete() */

/* This function will drain aen queue */
static int twa_aen_drain_queue(TW_Device_Extension *tw_dev, int no_check_reset)
{
	int request_id = 0;
	char cdb[TW_MAX_CDB_LEN];
	TW_SG_Entry sglist[1];
	int finished = 0, count = 0;
	TW_Command_Full *full_command_packet;
	TW_Command_Apache_Header *header;
	unsigned short aen;
	int first_reset = 0, queue = 0, retval = 1;

	if (no_check_reset)
		first_reset = 0;
	else
		first_reset = 1;

	full_command_packet = tw_dev->command_packet_virt[request_id];
	memset(full_command_packet, 0, sizeof(TW_Command_Full));

	/* Initialize cdb */
	memset(&cdb, 0, TW_MAX_CDB_LEN);
	cdb[0] = REQUEST_SENSE; /* opcode */
	cdb[4] = TW_ALLOCATION_LENGTH; /* allocation length */

	/* Initialize sglist */
	memset(&sglist, 0, sizeof(TW_SG_Entry));
	sglist[0].length = TW_SECTOR_SIZE;
	sglist[0].address = tw_dev->generic_buffer_phys[request_id];

	if (sglist[0].address & TW_ALIGNMENT_9000_SGL) {
		TW_PRINTK(tw_dev->host, TW_DRIVER, 0x1, "Found unaligned address during AEN drain");
		goto out;
	}

	/* Mark internal command */
	tw_dev->srb[request_id] = NULL;

	do {
		/* Send command to the board */
		if (twa_scsiop_execute_scsi(tw_dev, request_id, cdb, 1, sglist)) {
			TW_PRINTK(tw_dev->host, TW_DRIVER, 0x2, "Error posting request sense");
			goto out;
		}

		/* Now poll for completion */
		if (twa_poll_response(tw_dev, request_id, 30)) {
			TW_PRINTK(tw_dev->host, TW_DRIVER, 0x3, "No valid response while draining AEN queue");
			tw_dev->posted_request_count--;
			goto out;
		}

		tw_dev->posted_request_count--;
		header = (TW_Command_Apache_Header *)tw_dev->generic_buffer_virt[request_id];
		aen = header->status_block.error;
		queue = 0;
		count++;

		switch (aen) {
		case TW_AEN_QUEUE_EMPTY:
			if (first_reset != 1)
				goto out;
			else
				finished = 1;
			break;
		case TW_AEN_SOFT_RESET:
			if (first_reset == 0)
				first_reset = 1;
			else
				queue = 1;
			break;
		case TW_AEN_SYNC_TIME_WITH_HOST:
			break;
		default:
			queue = 1;
		}

		/* Now queue an event info */
		if (queue)
			twa_aen_queue_event(tw_dev, header);
	} while ((finished == 0) && (count < TW_MAX_AEN_DRAIN));

	if (count == TW_MAX_AEN_DRAIN)
		goto out;

	retval = 0;
out:
	tw_dev->state[request_id] = TW_S_INITIAL;
	return retval;
} /* End twa_aen_drain_queue() */

/* This function will queue an event */
static void twa_aen_queue_event(TW_Device_Extension *tw_dev, TW_Command_Apache_Header *header)
{
	u32 local_time;
	struct timeval time;
	TW_Event *event;
	unsigned short aen;
	char host[16];
	char *error_str;

	tw_dev->aen_count++;

	/* Fill out event info */
	event = tw_dev->event_queue[tw_dev->error_index];

	/* Check for clobber */
	host[0] = '\0';
	if (tw_dev->host) {
		sprintf(host, " scsi%d:", tw_dev->host->host_no);
		if (event->retrieved == TW_AEN_NOT_RETRIEVED)
			tw_dev->aen_clobber = 1;
	}

	aen = header->status_block.error;
	memset(event, 0, sizeof(TW_Event));

	event->severity = TW_SEV_OUT(header->status_block.severity__reserved);
	do_gettimeofday(&time);
	local_time = (u32)(time.tv_sec - (sys_tz.tz_minuteswest * 60));
	event->time_stamp_sec = local_time;
	event->aen_code = aen;
	event->retrieved = TW_AEN_NOT_RETRIEVED;
	event->sequence_id = tw_dev->error_sequence_id;
	tw_dev->error_sequence_id++;

	/* Check for embedded error string */
	error_str = &(header->err_specific_desc[strlen(header->err_specific_desc)+1]);

	header->err_specific_desc[sizeof(header->err_specific_desc) - 1] = '\0';
	event->parameter_len = strlen(header->err_specific_desc);
	memcpy(event->parameter_data, header->err_specific_desc, event->parameter_len);
	if (event->severity != TW_AEN_SEVERITY_DEBUG)
		printk(KERN_WARNING "3w-9xxx:%s AEN: %s (0x%02X:0x%04X): %s:%s.\n",
		       host,
		       twa_aen_severity_lookup(TW_SEV_OUT(header->status_block.severity__reserved)),
		       TW_MESSAGE_SOURCE_CONTROLLER_EVENT, aen,
		       error_str[0] == '\0' ? twa_string_lookup(twa_aen_table, aen) : error_str,
		       header->err_specific_desc);
	else
		tw_dev->aen_count--;

	if ((tw_dev->error_index + 1) == TW_Q_LENGTH)
		tw_dev->event_queue_wrapped = 1;
	tw_dev->error_index = (tw_dev->error_index + 1 ) % TW_Q_LENGTH;
} /* End twa_aen_queue_event() */

/* This function will read the aen queue from the isr */
static int twa_aen_read_queue(TW_Device_Extension *tw_dev, int request_id)
{
	char cdb[TW_MAX_CDB_LEN];
	TW_SG_Entry sglist[1];
	TW_Command_Full *full_command_packet;
	int retval = 1;

	full_command_packet = tw_dev->command_packet_virt[request_id];
	memset(full_command_packet, 0, sizeof(TW_Command_Full));

	/* Initialize cdb */
	memset(&cdb, 0, TW_MAX_CDB_LEN);
	cdb[0] = REQUEST_SENSE; /* opcode */
	cdb[4] = TW_ALLOCATION_LENGTH; /* allocation length */

	/* Initialize sglist */
	memset(&sglist, 0, sizeof(TW_SG_Entry));
	sglist[0].length = TW_SECTOR_SIZE;
	sglist[0].address = tw_dev->generic_buffer_phys[request_id];

	/* Mark internal command */
	tw_dev->srb[request_id] = NULL;

	/* Now post the command packet */
	if (twa_scsiop_execute_scsi(tw_dev, request_id, cdb, 1, sglist)) {
		TW_PRINTK(tw_dev->host, TW_DRIVER, 0x4, "Post failed while reading AEN queue");
		goto out;
	}
	retval = 0;
out:
	return retval;
} /* End twa_aen_read_queue() */

/* This function will look up an AEN severity string */
static char *twa_aen_severity_lookup(unsigned char severity_code)
{
	char *retval = NULL;

	if ((severity_code < (unsigned char) TW_AEN_SEVERITY_ERROR) ||
	    (severity_code > (unsigned char) TW_AEN_SEVERITY_DEBUG))
		goto out;

	retval = twa_aen_severity_table[severity_code];
out:
	return retval;
} /* End twa_aen_severity_lookup() */

/* This function will sync firmware time with the host time */
static void twa_aen_sync_time(TW_Device_Extension *tw_dev, int request_id)
{
	u32 schedulertime;
	struct timeval utc;
	TW_Command_Full *full_command_packet;
	TW_Command *command_packet;
	TW_Param_Apache *param;
	u32 local_time;

	/* Fill out the command packet */
	full_command_packet = tw_dev->command_packet_virt[request_id];
	memset(full_command_packet, 0, sizeof(TW_Command_Full));
	command_packet = &full_command_packet->command.oldcommand;
	command_packet->opcode__sgloffset = TW_OPSGL_IN(2, TW_OP_SET_PARAM);
	command_packet->request_id = request_id;
	command_packet->byte8_offset.param.sgl[0].address = tw_dev->generic_buffer_phys[request_id];
	command_packet->byte8_offset.param.sgl[0].length = TW_SECTOR_SIZE;
	command_packet->size = TW_COMMAND_SIZE;
	command_packet->byte6_offset.parameter_count = 1;

	/* Setup the param */
	param = (TW_Param_Apache *)tw_dev->generic_buffer_virt[request_id];
	memset(param, 0, TW_SECTOR_SIZE);
	param->table_id = TW_TIMEKEEP_TABLE | 0x8000; /* Controller time keep table */
	param->parameter_id = 0x3; /* SchedulerTime */
	param->parameter_size_bytes = 4;

	/* Convert system time in UTC to local time seconds since last 
           Sunday 12:00AM */
	do_gettimeofday(&utc);
	local_time = (u32)(utc.tv_sec - (sys_tz.tz_minuteswest * 60));
	schedulertime = local_time - (3 * 86400);
	schedulertime = schedulertime % 604800;

	memcpy(param->data, &schedulertime, sizeof(u32));

	/* Mark internal command */
	tw_dev->srb[request_id] = NULL;

	/* Now post the command */
	twa_post_command_packet(tw_dev, request_id, 1);
} /* End twa_aen_sync_time() */

/* This function will allocate memory and check if it is correctly aligned */
static int twa_allocate_memory(TW_Device_Extension *tw_dev, int size, int which)
{
	int i;
	dma_addr_t dma_handle;
	unsigned long *cpu_addr;
	int retval = 1;

	cpu_addr = pci_alloc_consistent(tw_dev->tw_pci_dev, size*TW_Q_LENGTH, &dma_handle);
	if (!cpu_addr) {
		TW_PRINTK(tw_dev->host, TW_DRIVER, 0x5, "Memory allocation failed");
		goto out;
	}

	if ((unsigned long)cpu_addr % (TW_ALIGNMENT_9000)) {
		TW_PRINTK(tw_dev->host, TW_DRIVER, 0x6, "Failed to allocate correctly aligned memory");
		pci_free_consistent(tw_dev->tw_pci_dev, size*TW_Q_LENGTH, cpu_addr, dma_handle);
		goto out;
	}

	memset(cpu_addr, 0, size*TW_Q_LENGTH);

	for (i = 0; i < TW_Q_LENGTH; i++) {
		switch(which) {
		case 0:
			tw_dev->command_packet_phys[i] = dma_handle+(i*size);
			tw_dev->command_packet_virt[i] = (TW_Command_Full *)((unsigned char *)cpu_addr + (i*size));
			break;
		case 1:
			tw_dev->generic_buffer_phys[i] = dma_handle+(i*size);
			tw_dev->generic_buffer_virt[i] = (unsigned long *)((unsigned char *)cpu_addr + (i*size));
			break;
		}
	}
	retval = 0;
out:
	return retval;
} /* End twa_allocate_memory() */

/* This function will check the status register for unexpected bits */
static int twa_check_bits(u32 status_reg_value)
{
	int retval = 1;

	if ((status_reg_value & TW_STATUS_EXPECTED_BITS) != TW_STATUS_EXPECTED_BITS)
		goto out;
	if ((status_reg_value & TW_STATUS_UNEXPECTED_BITS) != 0)
		goto out;

	retval = 0;
out:
	return retval;
} /* End twa_check_bits() */

/* This function will check the srl and decide if we are compatible  */
static int twa_check_srl(TW_Device_Extension *tw_dev, int *flashed)
{
	int retval = 1;
	unsigned short fw_on_ctlr_srl = 0, fw_on_ctlr_arch_id = 0;
	unsigned short fw_on_ctlr_branch = 0, fw_on_ctlr_build = 0;
	u32 init_connect_result = 0;

	if (twa_initconnection(tw_dev, TW_INIT_MESSAGE_CREDITS,
			       TW_EXTENDED_INIT_CONNECT, TW_CURRENT_DRIVER_SRL,
			       TW_9000_ARCH_ID, TW_CURRENT_DRIVER_BRANCH,
			       TW_CURRENT_DRIVER_BUILD, &fw_on_ctlr_srl,
			       &fw_on_ctlr_arch_id, &fw_on_ctlr_branch,
			       &fw_on_ctlr_build, &init_connect_result)) {
		TW_PRINTK(tw_dev->host, TW_DRIVER, 0x7, "Initconnection failed while checking SRL");
		goto out;
	}

	tw_dev->working_srl = fw_on_ctlr_srl;
	tw_dev->working_branch = fw_on_ctlr_branch;
	tw_dev->working_build = fw_on_ctlr_build;

	/* Try base mode compatibility */
	if (!(init_connect_result & TW_CTLR_FW_COMPATIBLE)) {
		if (twa_initconnection(tw_dev, TW_INIT_MESSAGE_CREDITS,
				       TW_EXTENDED_INIT_CONNECT,
				       TW_BASE_FW_SRL, TW_9000_ARCH_ID,
				       TW_BASE_FW_BRANCH, TW_BASE_FW_BUILD,
				       &fw_on_ctlr_srl, &fw_on_ctlr_arch_id,
				       &fw_on_ctlr_branch, &fw_on_ctlr_build,
				       &init_connect_result)) {
			TW_PRINTK(tw_dev->host, TW_DRIVER, 0xa, "Initconnection (base mode) failed while checking SRL");
			goto out;
		}
		if (!(init_connect_result & TW_CTLR_FW_COMPATIBLE)) {
			if (TW_CURRENT_DRIVER_SRL > fw_on_ctlr_srl) {
				TW_PRINTK(tw_dev->host, TW_DRIVER, 0x32, "Firmware and driver incompatibility: please upgrade firmware");
			} else {
				TW_PRINTK(tw_dev->host, TW_DRIVER, 0x33, "Firmware and driver incompatibility: please upgrade driver");
			}
			goto out;
		}
		tw_dev->working_srl = TW_BASE_FW_SRL;
		tw_dev->working_branch = TW_BASE_FW_BRANCH;
		tw_dev->working_build = TW_BASE_FW_BUILD;
	}
	retval = 0;
out:
	return retval;
} /* End twa_check_srl() */

/* This function handles ioctl for the character device */
static int twa_chrdev_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
{
	long timeout;
	unsigned long *cpu_addr, data_buffer_length_adjusted = 0, flags = 0;
	dma_addr_t dma_handle;
	int request_id = 0;
	unsigned int sequence_id = 0;
	unsigned char event_index, start_index;
	TW_Ioctl_Driver_Command driver_command;
	TW_Ioctl_Buf_Apache *tw_ioctl;
	TW_Lock *tw_lock;
	TW_Command_Full *full_command_packet;
	TW_Compatibility_Info *tw_compat_info;
	TW_Event *event;
	struct timeval current_time;
	u32 current_time_ms;
	TW_Device_Extension *tw_dev = twa_device_extension_list[iminor(inode)];
	int retval = TW_IOCTL_ERROR_OS_EFAULT;
	void __user *argp = (void __user *)arg;

	/* Only let one of these through at a time */
	if (down_interruptible(&tw_dev->ioctl_sem)) {
		retval = TW_IOCTL_ERROR_OS_EINTR;
		goto out;
	}

	/* First copy down the driver command */
	if (copy_from_user(&driver_command, argp, sizeof(TW_Ioctl_Driver_Command)))
		goto out2;

	/* Check data buffer size */
	if (driver_command.buffer_length > TW_MAX_SECTORS * 512) {
		retval = TW_IOCTL_ERROR_OS_EINVAL;
		goto out2;
	}

	/* Hardware can only do multiple of 512 byte transfers */
	data_buffer_length_adjusted = (driver_command.buffer_length + 511) & ~511;

	/* Now allocate ioctl buf memory */
	cpu_addr = dma_alloc_coherent(&tw_dev->tw_pci_dev->dev, data_buffer_length_adjusted+sizeof(TW_Ioctl_Buf_Apache) - 1, &dma_handle, GFP_KERNEL);
	if (!cpu_addr) {
		retval = TW_IOCTL_ERROR_OS_ENOMEM;
		goto out2;
	}

	tw_ioctl = (TW_Ioctl_Buf_Apache *)cpu_addr;

	/* Now copy down the entire ioctl */
	if (copy_from_user(tw_ioctl, argp, driver_command.buffer_length + sizeof(TW_Ioctl_Buf_Apache) - 1))
		goto out3;

	/* See which ioctl we are doing */
	switch (cmd) {
	case TW_IOCTL_FIRMWARE_PASS_THROUGH:
		spin_lock_irqsave(tw_dev->host->host_lock, flags);
		twa_get_request_id(tw_dev, &request_id);

		/* Flag internal command */
		tw_dev->srb[request_id] = NULL;

		/* Flag chrdev ioctl */
		tw_dev->chrdev_request_id = request_id;

		full_command_packet = &tw_ioctl->firmware_command;

		/* Load request id and sglist for both command types */
		twa_load_sgl(full_command_packet, request_id, dma_handle, data_buffer_length_adjusted);

		memcpy(tw_dev->command_packet_virt[request_id], &(tw_ioctl->firmware_command), sizeof(TW_Command_Full));

		/* Now post the command packet to the controller */
		twa_post_command_packet(tw_dev, request_id, 1);
		spin_unlock_irqrestore(tw_dev->host->host_lock, flags);

		timeout = TW_IOCTL_CHRDEV_TIMEOUT*HZ;

		/* Now wait for command to complete */
		timeout = wait_event_timeout(tw_dev->ioctl_wqueue, tw_dev->chrdev_request_id == TW_IOCTL_CHRDEV_FREE, timeout);

		/* See if we reset while waiting for the ioctl to complete */
		if (test_bit(TW_IN_RESET, &tw_dev->flags)) {
			clear_bit(TW_IN_RESET, &tw_dev->flags);
			retval = TW_IOCTL_ERROR_OS_ERESTARTSYS;
			goto out3;
		}

		/* We timed out, and didn't get an interrupt */
		if (tw_dev->chrdev_request_id != TW_IOCTL_CHRDEV_FREE) {
			/* Now we need to reset the board */
			printk(KERN_WARNING "3w-9xxx: scsi%d: WARNING: (0x%02X:0x%04X): Character ioctl (0x%x) timed out, resetting card.\n",
			       tw_dev->host->host_no, TW_DRIVER, 0xc,
			       cmd);
			retval = TW_IOCTL_ERROR_OS_EIO;
			spin_lock_irqsave(tw_dev->host->host_lock, flags);
			tw_dev->state[request_id] = TW_S_COMPLETED;
			twa_free_request_id(tw_dev, request_id);
			tw_dev->posted_request_count--;
			spin_unlock_irqrestore(tw_dev->host->host_lock, flags);
			twa_reset_device_extension(tw_dev, 1);
			goto out3;
		}

		/* Now copy in the command packet response */
		memcpy(&(tw_ioctl->firmware_command), tw_dev->command_packet_virt[request_id], sizeof(TW_Command_Full));
		
		/* Now complete the io */
		spin_lock_irqsave(tw_dev->host->host_lock, flags);
		tw_dev->posted_request_count--;
		tw_dev->state[request_id] = TW_S_COMPLETED;
		twa_free_request_id(tw_dev, request_id);
		spin_unlock_irqrestore(tw_dev->host->host_lock, flags);
		break;
	case TW_IOCTL_GET_COMPATIBILITY_INFO:
		tw_ioctl->driver_command.status = 0;
		/* Copy compatiblity struct into ioctl data buffer */
		tw_compat_info = (TW_Compatibility_Info *)tw_ioctl->data_buffer;
		strncpy(tw_compat_info->driver_version, TW_DRIVER_VERSION, strlen(TW_DRIVER_VERSION));
		tw_compat_info->working_srl = tw_dev->working_srl;
		tw_compat_info->working_branch = tw_dev->working_branch;
		tw_compat_info->working_build = tw_dev->working_build;
		tw_compat_info->driver_srl_high = TW_CURRENT_DRIVER_SRL;
		tw_compat_info->driver_branch_high = TW_CURRENT_DRIVER_BRANCH;
		tw_compat_info->driver_build_high = TW_CURRENT_DRIVER_BUILD;
		tw_compat_info->driver_srl_low = TW_BASE_FW_SRL;
		tw_compat_info->driver_branch_low = TW_BASE_FW_BRANCH;
		tw_compat_info->driver_build_low = TW_BASE_FW_BUILD;
		break;
	case TW_IOCTL_GET_LAST_EVENT:
		if (tw_dev->event_queue_wrapped) {
			if (tw_dev->aen_clobber) {
				tw_ioctl->driver_command.status = TW_IOCTL_ERROR_STATUS_AEN_CLOBBER;
				tw_dev->aen_clobber = 0;
			} else
				tw_ioctl->driver_command.status = 0;
		} else {
			if (!tw_dev->error_index) {
				tw_ioctl->driver_command.status = TW_IOCTL_ERROR_STATUS_NO_MORE_EVENTS;
				break;
			}
			tw_ioctl->driver_command.status = 0;
		}
		event_index = (tw_dev->error_index - 1 + TW_Q_LENGTH) % TW_Q_LENGTH;
		memcpy(tw_ioctl->data_buffer, tw_dev->event_queue[event_index], sizeof(TW_Event));
		tw_dev->event_queue[event_index]->retrieved = TW_AEN_RETRIEVED;
		break;
	case TW_IOCTL_GET_FIRST_EVENT:
		if (tw_dev->event_queue_wrapped) {
			if (tw_dev->aen_clobber) {
				tw_ioctl->driver_command.status = TW_IOCTL_ERROR_STATUS_AEN_CLOBBER;
				tw_dev->aen_clobber = 0;
			} else 
				tw_ioctl->driver_command.status = 0;
			event_index = tw_dev->error_index;
		} else {
			if (!tw_dev->error_index) {
				tw_ioctl->driver_command.status = TW_IOCTL_ERROR_STATUS_NO_MORE_EVENTS;
				break;
			}
			tw_ioctl->driver_command.status = 0;
			event_index = 0;
		}
		memcpy(tw_ioctl->data_buffer, tw_dev->event_queue[event_index], sizeof(TW_Event));
		tw_dev->event_queue[event_index]->retrieved = TW_AEN_RETRIEVED;
		break;
	case TW_IOCTL_GET_NEXT_EVENT:
		event = (TW_Event *)tw_ioctl->data_buffer;
		sequence_id = event->sequence_id;
		tw_ioctl->driver_command.status = 0;

		if (tw_dev->event_queue_wrapped) {
			if (tw_dev->aen_clobber) {
				tw_ioctl->driver_command.status = TW_IOCTL_ERROR_STATUS_AEN_CLOBBER;
				tw_dev->aen_clobber = 0;
			}
			start_index = tw_dev->error_index;
		} else {
			if (!tw_dev->error_index) {
				tw_ioctl->driver_command.status = TW_IOCTL_ERROR_STATUS_NO_MORE_EVENTS;
				break;
			}
			start_index = 0;
		}
		event_index = (start_index + sequence_id - tw_dev->event_queue[start_index]->sequence_id + 1) % TW_Q_LENGTH;

		if (!(tw_dev->event_queue[event_index]->sequence_id > sequence_id)) {
			if (tw_ioctl->driver_command.status == TW_IOCTL_ERROR_STATUS_AEN_CLOBBER)
				tw_dev->aen_clobber = 1;
			tw_ioctl->driver_command.status = TW_IOCTL_ERROR_STATUS_NO_MORE_EVENTS;
			break;
		}
		memcpy(tw_ioctl->data_buffer, tw_dev->event_queue[event_index], sizeof(TW_Event));
		tw_dev->event_queue[event_index]->retrieved = TW_AEN_RETRIEVED;
		break;
	case TW_IOCTL_GET_PREVIOUS_EVENT:
		event = (TW_Event *)tw_ioctl->data_buffer;
		sequence_id = event->sequence_id;
		tw_ioctl->driver_command.status = 0;

		if (tw_dev->event_queue_wrapped) {
			if (tw_dev->aen_clobber) {
				tw_ioctl->driver_command.status = TW_IOCTL_ERROR_STATUS_AEN_CLOBBER;
				tw_dev->aen_clobber = 0;
			}
			start_index = tw_dev->error_index;
		} else {
			if (!tw_dev->error_index) {
				tw_ioctl->driver_command.status = TW_IOCTL_ERROR_STATUS_NO_MORE_EVENTS;
				break;
			}
			start_index = 0;
		}
		event_index = (start_index + sequence_id - tw_dev->event_queue[start_index]->sequence_id - 1) % TW_Q_LENGTH;

		if (!(tw_dev->event_queue[event_index]->sequence_id < sequence_id)) {
			if (tw_ioctl->driver_command.status == TW_IOCTL_ERROR_STATUS_AEN_CLOBBER)
				tw_dev->aen_clobber = 1;
			tw_ioctl->driver_command.status = TW_IOCTL_ERROR_STATUS_NO_MORE_EVENTS;
			break;
		}
		memcpy(tw_ioctl->data_buffer, tw_dev->event_queue[event_index], sizeof(TW_Event));
		tw_dev->event_queue[event_index]->retrieved = TW_AEN_RETRIEVED;
		break;
	case TW_IOCTL_GET_LOCK:
		tw_lock = (TW_Lock *)tw_ioctl->data_buffer;
		do_gettimeofday(&current_time);
		current_time_ms = (current_time.tv_sec * 1000) + (current_time.tv_usec / 1000);

		if ((tw_lock->force_flag == 1) || (tw_dev->ioctl_sem_lock == 0) || (current_time_ms >= tw_dev->ioctl_msec)) {
			tw_dev->ioctl_sem_lock = 1;
			tw_dev->ioctl_msec = current_time_ms + tw_lock->timeout_msec;
			tw_ioctl->driver_command.status = 0;
			tw_lock->time_remaining_msec = tw_lock->timeout_msec;
		} else {
			tw_ioctl->driver_command.status = TW_IOCTL_ERROR_STATUS_LOCKED;
			tw_lock->time_remaining_msec = tw_dev->ioctl_msec - current_time_ms;
		}
		break;
	case TW_IOCTL_RELEASE_LOCK:
		if (tw_dev->ioctl_sem_lock == 1) {
			tw_dev->ioctl_sem_lock = 0;
			tw_ioctl->driver_command.status = 0;
		} else {
			tw_ioctl->driver_command.status = TW_IOCTL_ERROR_STATUS_NOT_LOCKED;
		}
		break;
	default:
		retval = TW_IOCTL_ERROR_OS_ENOTTY;
		goto out3;
	}

	/* Now copy the entire response to userspace */
	if (copy_to_user(argp, tw_ioctl, sizeof(TW_Ioctl_Buf_Apache) + driver_command.buffer_length - 1) == 0)
		retval = 0;
out3:
	/* Now free ioctl buf memory */
	dma_free_coherent(&tw_dev->tw_pci_dev->dev, data_buffer_length_adjusted+sizeof(TW_Ioctl_Buf_Apache) - 1, cpu_addr, dma_handle);
out2:
	up(&tw_dev->ioctl_sem);
out:
	return retval;
} /* End twa_chrdev_ioctl() */

/* This function handles open for the character device */
static int twa_chrdev_open(struct inode *inode, struct file *file)
{
	unsigned int minor_number;
	int retval = TW_IOCTL_ERROR_OS_ENODEV;

	minor_number = iminor(inode);
	if (minor_number >= twa_device_extension_count)
		goto out;
	retval = 0;
out:
	return retval;
} /* End twa_chrdev_open() */

/* This function will print readable messages from status register errors */
static int twa_decode_bits(TW_Device_Extension *tw_dev, u32 status_reg_value)
{
	int retval = 1;

	/* Check for various error conditions and handle them appropriately */
	if (status_reg_value & TW_STATUS_PCI_PARITY_ERROR) {
		TW_PRINTK(tw_dev->host, TW_DRIVER, 0xc, "PCI Parity Error: clearing");
		writel(TW_CONTROL_CLEAR_PARITY_ERROR, TW_CONTROL_REG_ADDR(tw_dev));
	}

	if (status_reg_value & TW_STATUS_PCI_ABORT) {
		TW_PRINTK(tw_dev->host, TW_DRIVER, 0xd, "PCI Abort: clearing");
		writel(TW_CONTROL_CLEAR_PCI_ABORT, TW_CONTROL_REG_ADDR(tw_dev));
		pci_write_config_word(tw_dev->tw_pci_dev, PCI_STATUS, TW_PCI_CLEAR_PCI_ABORT);
	}

	if (status_reg_value & TW_STATUS_QUEUE_ERROR) {
		TW_PRINTK(tw_dev->host, TW_DRIVER, 0xe, "Controller Queue Error: clearing");
		writel(TW_CONTROL_CLEAR_QUEUE_ERROR, TW_CONTROL_REG_ADDR(tw_dev));
	}

	if (status_reg_value & TW_STATUS_SBUF_WRITE_ERROR) {
		TW_PRINTK(tw_dev->host, TW_DRIVER, 0xf, "SBUF Write Error: clearing");
		writel(TW_CONTROL_CLEAR_SBUF_WRITE_ERROR, TW_CONTROL_REG_ADDR(tw_dev));
	}

	if (status_reg_value & TW_STATUS_MICROCONTROLLER_ERROR) {
		if (tw_dev->reset_print == 0) {
			TW_PRINTK(tw_dev->host, TW_DRIVER, 0x10, "Microcontroller Error: clearing");
			tw_dev->reset_print = 1;
		}
		goto out;
	}
	retval = 0;
out:
	return retval;
} /* End twa_decode_bits() */

/* This function will empty the response queue */
static int twa_empty_response_queue(TW_Device_Extension *tw_dev)
{
	u32 status_reg_value, response_que_value;
	int count = 0, retval = 1;

	status_reg_value = readl(TW_STATUS_REG_ADDR(tw_dev));

	while (((status_reg_value & TW_STATUS_RESPONSE_QUEUE_EMPTY) == 0) && (count < TW_MAX_RESPONSE_DRAIN)) {
		response_que_value = readl(TW_RESPONSE_QUEUE_REG_ADDR(tw_dev));
		status_reg_value = readl(TW_STATUS_REG_ADDR(tw_dev));
		count++;
	}
	if (count == TW_MAX_RESPONSE_DRAIN)
		goto out;

	retval = 0;
out:
	return retval;
} /* End twa_empty_response_queue() */

/* This function passes sense keys from firmware to scsi layer */
static int twa_fill_sense(TW_Device_Extension *tw_dev, int request_id, int copy_sense, int print_host)
{
	TW_Command_Full *full_command_packet;
	unsigned short error;
	int retval = 1;
	char *error_str;

	full_command_packet = tw_dev->command_packet_virt[request_id];

	/* Check for embedded error string */
	error_str = &(full_command_packet->header.err_specific_desc[strlen(full_command_packet->header.err_specific_desc) + 1]);

	/* Don't print error for Logical unit not supported during rollcall */
	error = full_command_packet->header.status_block.error;
	if ((error != TW_ERROR_LOGICAL_UNIT_NOT_SUPPORTED) && (error != TW_ERROR_UNIT_OFFLINE)) {
		if (print_host)
			printk(KERN_WARNING "3w-9xxx: scsi%d: ERROR: (0x%02X:0x%04X): %s:%s.\n",
			       tw_dev->host->host_no,
			       TW_MESSAGE_SOURCE_CONTROLLER_ERROR,
			       full_command_packet->header.status_block.error,
			       error_str[0] == '\0' ?
			       twa_string_lookup(twa_error_table,
						 full_command_packet->header.status_block.error) : error_str,
			       full_command_packet->header.err_specific_desc);
		else
			printk(KERN_WARNING "3w-9xxx: ERROR: (0x%02X:0x%04X): %s:%s.\n",
			       TW_MESSAGE_SOURCE_CONTROLLER_ERROR,
			       full_command_packet->header.status_block.error,
			       error_str[0] == '\0' ?
			       twa_string_lookup(twa_error_table,
						 full_command_packet->header.status_block.error) : error_str,
			       full_command_packet->header.err_specific_desc);
	}

	if (copy_sense) {
		memcpy(tw_dev->srb[request_id]->sense_buffer, full_command_packet->header.sense_data, TW_SENSE_DATA_LENGTH);
		tw_dev->srb[request_id]->result = (full_command_packet->command.newcommand.status << 1);
		retval = TW_ISR_DONT_RESULT;
		goto out;
	}
	retval = 0;
out:
	return retval;
} /* End twa_fill_sense() */

/* This function will free up device extension resources */
static void twa_free_device_extension(TW_Device_Extension *tw_dev)
{
	if (tw_dev->command_packet_virt[0])
		pci_free_consistent(tw_dev->tw_pci_dev,
				    sizeof(TW_Command_Full)*TW_Q_LENGTH,
				    tw_dev->command_packet_virt[0],
				    tw_dev->command_packet_phys[0]);

	if (tw_dev->generic_buffer_virt[0])
		pci_free_consistent(tw_dev->tw_pci_dev,
				    TW_SECTOR_SIZE*TW_Q_LENGTH,
				    tw_dev->generic_buffer_virt[0],
				    tw_dev->generic_buffer_phys[0]);

	if (tw_dev->event_queue[0])
		kfree(tw_dev->event_queue[0]);
} /* End twa_free_device_extension() */

/* This function will free a request id */
static void twa_free_request_id(TW_Device_Extension *tw_dev, int request_id)
{
	tw_dev->free_queue[tw_dev->free_tail] = request_id;
	tw_dev->state[request_id] = TW_S_FINISHED;
	tw_dev->free_tail = (tw_dev->free_tail + 1) % TW_Q_LENGTH;
} /* End twa_free_request_id() */

/* This function will get parameter table entires from the firmware */
static void *twa_get_param(TW_Device_Extension *tw_dev, int request_id, int table_id, int parameter_id, int parameter_size_bytes)
{
	TW_Command_Full *full_command_packet;
	TW_Command *command_packet;
	TW_Param_Apache *param;
	unsigned long param_value;
	void *retval = NULL;

	/* Setup the command packet */
	full_command_packet = tw_dev->command_packet_virt[request_id];
	memset(full_command_packet, 0, sizeof(TW_Command_Full));
	command_packet = &full_command_packet->command.oldcommand;

	command_packet->opcode__sgloffset = TW_OPSGL_IN(2, TW_OP_GET_PARAM);
	command_packet->size              = TW_COMMAND_SIZE;
	command_packet->request_id        = request_id;
	command_packet->byte6_offset.block_count = 1;

	/* Now setup the param */
	param = (TW_Param_Apache *)tw_dev->generic_buffer_virt[request_id];
	memset(param, 0, TW_SECTOR_SIZE);
	param->table_id = table_id | 0x8000;
	param->parameter_id = parameter_id;
	param->parameter_size_bytes = parameter_size_bytes;
	param_value = tw_dev->generic_buffer_phys[request_id];

	command_packet->byte8_offset.param.sgl[0].address = param_value;
	command_packet->byte8_offset.param.sgl[0].length = TW_SECTOR_SIZE;

	/* Post the command packet to the board */
	twa_post_command_packet(tw_dev, request_id, 1);

	/* Poll for completion */
	if (twa_poll_response(tw_dev, request_id, 30))
		TW_PRINTK(tw_dev->host, TW_DRIVER, 0x13, "No valid response during get param")
	else
		retval = (void *)&(param->data[0]);

	tw_dev->posted_request_count--;
	tw_dev->state[request_id] = TW_S_INITIAL;

	return retval;
} /* End twa_get_param() */

/* This function will assign an available request id */
static void twa_get_request_id(TW_Device_Extension *tw_dev, int *request_id)
{
	*request_id = tw_dev->free_queue[tw_dev->free_head];
	tw_dev->free_head = (tw_dev->free_head + 1) % TW_Q_LENGTH;
	tw_dev->state[*request_id] = TW_S_STARTED;
} /* End twa_get_request_id() */

/* This function will send an initconnection command to controller */
static int twa_initconnection(TW_Device_Extension *tw_dev, int message_credits,
 			      u32 set_features, unsigned short current_fw_srl, 
			      unsigned short current_fw_arch_id, 
			      unsigned short current_fw_branch, 
			      unsigned short current_fw_build, 
			      unsigned short *fw_on_ctlr_srl, 
			      unsigned short *fw_on_ctlr_arch_id, 
			      unsigned short *fw_on_ctlr_branch, 
			      unsigned short *fw_on_ctlr_build, 
			      u32 *init_connect_result)
{
	TW_Command_Full *full_command_packet;
	TW_Initconnect *tw_initconnect;
	int request_id = 0, retval = 1;

	/* Initialize InitConnection command packet */
	full_command_packet = tw_dev->command_packet_virt[request_id];
	memset(full_command_packet, 0, sizeof(TW_Command_Full));
	full_command_packet->header.header_desc.size_header = 128;
	
	tw_initconnect = (TW_Initconnect *)&full_command_packet->command.oldcommand;
	tw_initconnect->opcode__reserved = TW_OPRES_IN(0, TW_OP_INIT_CONNECTION);
	tw_initconnect->request_id = request_id;
	tw_initconnect->message_credits = message_credits;
	tw_initconnect->features = set_features;

	/* Turn on 64-bit sgl support if we need to */
	tw_initconnect->features |= sizeof(dma_addr_t) > 4 ? 1 : 0;

	if (set_features & TW_EXTENDED_INIT_CONNECT) {
		tw_initconnect->size = TW_INIT_COMMAND_PACKET_SIZE_EXTENDED;
		tw_initconnect->fw_srl = current_fw_srl;
		tw_initconnect->fw_arch_id = current_fw_arch_id;
		tw_initconnect->fw_branch = current_fw_branch;
		tw_initconnect->fw_build = current_fw_build;
	} else 
		tw_initconnect->size = TW_INIT_COMMAND_PACKET_SIZE;

	/* Send command packet to the board */
	twa_post_command_packet(tw_dev, request_id, 1);

	/* Poll for completion */
	if (twa_poll_response(tw_dev, request_id, 30)) {
		TW_PRINTK(tw_dev->host, TW_DRIVER, 0x15, "No valid response during init connection");
	} else {
		if (set_features & TW_EXTENDED_INIT_CONNECT) {
			*fw_on_ctlr_srl = tw_initconnect->fw_srl;
			*fw_on_ctlr_arch_id = tw_initconnect->fw_arch_id;
			*fw_on_ctlr_branch = tw_initconnect->fw_branch;
			*fw_on_ctlr_build = tw_initconnect->fw_build;
			*init_connect_result = tw_initconnect->result;
		}
		retval = 0;
	}

	tw_dev->posted_request_count--;
	tw_dev->state[request_id] = TW_S_INITIAL;

	return retval;
} /* End twa_initconnection() */

/* This function will initialize the fields of a device extension */
static int twa_initialize_device_extension(TW_Device_Extension *tw_dev)
{
	int i, retval = 1;

	/* Initialize command packet buffers */
	if (twa_allocate_memory(tw_dev, sizeof(TW_Command_Full), 0)) {
		TW_PRINTK(tw_dev->host, TW_DRIVER, 0x16, "Command packet memory allocation failed");
		goto out;
	}

	/* Initialize generic buffer */
	if (twa_allocate_memory(tw_dev, TW_SECTOR_SIZE, 1)) {
		TW_PRINTK(tw_dev->host, TW_DRIVER, 0x17, "Generic memory allocation failed");
		goto out;
	}

	/* Allocate event info space */
	tw_dev->event_queue[0] = kmalloc(sizeof(TW_Event) * TW_Q_LENGTH, GFP_KERNEL);
	if (!tw_dev->event_queue[0]) {
		TW_PRINTK(tw_dev->host, TW_DRIVER, 0x18, "Event info memory allocation failed");
		goto out;
	}

	memset(tw_dev->event_queue[0], 0, sizeof(TW_Event) * TW_Q_LENGTH);

	for (i = 0; i < TW_Q_LENGTH; i++) {
		tw_dev->event_queue[i] = (TW_Event *)((unsigned char *)tw_dev->event_queue[0] + (i * sizeof(TW_Event)));
		tw_dev->free_queue[i] = i;
		tw_dev->state[i] = TW_S_INITIAL;
	}

	tw_dev->pending_head = TW_Q_START;
	tw_dev->pending_tail = TW_Q_START;
	tw_dev->free_head = TW_Q_START;
	tw_dev->free_tail = TW_Q_START;
	tw_dev->error_sequence_id = 1;
	tw_dev->chrdev_request_id = TW_IOCTL_CHRDEV_FREE;

	init_MUTEX(&tw_dev->ioctl_sem);
	init_waitqueue_head(&tw_dev->ioctl_wqueue);

	retval = 0;
out:
	return retval;
} /* End twa_initialize_device_extension() */

/* This function is the interrupt service routine */
static irqreturn_t twa_interrupt(int irq, void *dev_instance, struct pt_regs *regs)
{
	int request_id, error = 0;
	u32 status_reg_value;
	TW_Response_Queue response_que;
	TW_Command_Full *full_command_packet;
	TW_Command *command_packet;
	TW_Device_Extension *tw_dev = (TW_Device_Extension *)dev_instance;
	int handled = 0;

	/* Get the per adapter lock */
	spin_lock(tw_dev->host->host_lock);

	/* Read the registers */
	status_reg_value = readl(TW_STATUS_REG_ADDR(tw_dev));

	/* Check if this is our interrupt, otherwise bail */
	if (!(status_reg_value & TW_STATUS_VALID_INTERRUPT))
		goto twa_interrupt_bail;

	handled = 1;

	/* Check controller for errors */
	if (twa_check_bits(status_reg_value)) {
		if (twa_decode_bits(tw_dev, status_reg_value)) {
			TW_CLEAR_ALL_INTERRUPTS(tw_dev);
			goto twa_interrupt_bail;
		}
	}

	/* Handle host interrupt */
	if (status_reg_value & TW_STATUS_HOST_INTERRUPT)
		TW_CLEAR_HOST_INTERRUPT(tw_dev);

	/* Handle attention interrupt */
	if (status_reg_value & TW_STATUS_ATTENTION_INTERRUPT) {
		TW_CLEAR_ATTENTION_INTERRUPT(tw_dev);
		if (!(test_and_set_bit(TW_IN_ATTENTION_LOOP, &tw_dev->flags))) {
			twa_get_request_id(tw_dev, &request_id);

			error = twa_aen_read_queue(tw_dev, request_id);
			if (error) {
				tw_dev->state[request_id] = TW_S_COMPLETED;
				twa_free_request_id(tw_dev, request_id);
				clear_bit(TW_IN_ATTENTION_LOOP, &tw_dev->flags);
			}
		}
	}

	/* Handle command interrupt */
	if (status_reg_value & TW_STATUS_COMMAND_INTERRUPT) {
		TW_MASK_COMMAND_INTERRUPT(tw_dev);
		/* Drain as many pending commands as we can */
		while (tw_dev->pending_request_count > 0) {
			request_id = tw_dev->pending_queue[tw_dev->pending_head];
			if (tw_dev->state[request_id] != TW_S_PENDING) {
				TW_PRINTK(tw_dev->host, TW_DRIVER, 0x19, "Found request id that wasn't pending");
				TW_CLEAR_ALL_INTERRUPTS(tw_dev);
				goto twa_interrupt_bail;
			}
			if (twa_post_command_packet(tw_dev, request_id, 1)==0) {
				tw_dev->pending_head = (tw_dev->pending_head + 1) % TW_Q_LENGTH;
				tw_dev->pending_request_count--;
			} else {
				/* If we get here, we will continue re-posting on the next command interrupt */
				break;
			}
		}
	}

	/* Handle response interrupt */
	if (status_reg_value & TW_STATUS_RESPONSE_INTERRUPT) {

		/* Drain the response queue from the board */
		while ((status_reg_value & TW_STATUS_RESPONSE_QUEUE_EMPTY) == 0) {
			/* Complete the response */
			response_que.value = readl(TW_RESPONSE_QUEUE_REG_ADDR(tw_dev));
			request_id = TW_RESID_OUT(response_que.response_id);
			full_command_packet = tw_dev->command_packet_virt[request_id];
			error = 0;
			command_packet = &full_command_packet->command.oldcommand;
			/* Check for command packet errors */
			if (full_command_packet->command.newcommand.status != 0) {
				if (tw_dev->srb[request_id] != 0) {
					error = twa_fill_sense(tw_dev, request_id, 1, 1);
				} else {
					/* Skip ioctl error prints */
					if (request_id != tw_dev->chrdev_request_id) {
						error = twa_fill_sense(tw_dev, request_id, 0, 1);
					}
				}
			}

			/* Check for correct state */
			if (tw_dev->state[request_id] != TW_S_POSTED) {
				if (tw_dev->srb[request_id] != 0) {
					TW_PRINTK(tw_dev->host, TW_DRIVER, 0x1a, "Received a request id that wasn't posted");
					TW_CLEAR_ALL_INTERRUPTS(tw_dev);
					goto twa_interrupt_bail;
				}
			}

			/* Check for internal command completion */
			if (tw_dev->srb[request_id] == 0) {
				if (request_id != tw_dev->chrdev_request_id) {
					if (twa_aen_complete(tw_dev, request_id))
						TW_PRINTK(tw_dev->host, TW_DRIVER, 0x1b, "Error completing AEN during attention interrupt");
				} else {
					tw_dev->chrdev_request_id = TW_IOCTL_CHRDEV_FREE;
					wake_up(&tw_dev->ioctl_wqueue);
				}
			} else {
				twa_scsiop_execute_scsi_complete(tw_dev, request_id);
				/* If no error command was a success */
				if (error == 0) {
					tw_dev->srb[request_id]->result = (DID_OK << 16);
				}

				/* If error, command failed */
				if (error == 1) {
					/* Ask for a host reset */
					tw_dev->srb[request_id]->result = (DID_OK << 16) | (CHECK_CONDITION << 1);
				}

				/* Report residual bytes for single sgl */
				if ((tw_dev->srb[request_id]->use_sg <= 1) && (full_command_packet->command.newcommand.status == 0)) {
					if (full_command_packet->command.newcommand.sg_list[0].length < tw_dev->srb[request_id]->request_bufflen)
						tw_dev->srb[request_id]->resid = tw_dev->srb[request_id]->request_bufflen - full_command_packet->command.newcommand.sg_list[0].length;
				}

				/* Now complete the io */
				tw_dev->state[request_id] = TW_S_COMPLETED;
				twa_free_request_id(tw_dev, request_id);
				tw_dev->posted_request_count--;
				tw_dev->srb[request_id]->scsi_done(tw_dev->srb[request_id]);
				twa_unmap_scsi_data(tw_dev, request_id);
			}

			/* Check for valid status after each drain */
			status_reg_value = readl(TW_STATUS_REG_ADDR(tw_dev));
			if (twa_check_bits(status_reg_value)) {
				if (twa_decode_bits(tw_dev, status_reg_value)) {
					TW_CLEAR_ALL_INTERRUPTS(tw_dev);
					goto twa_interrupt_bail;
				}
			}
		}
	}

twa_interrupt_bail:
	spin_unlock(tw_dev->host->host_lock);
	return IRQ_RETVAL(handled);
} /* End twa_interrupt() */

/* This function will load the request id and various sgls for ioctls */
static void twa_load_sgl(TW_Command_Full *full_command_packet, int request_id, dma_addr_t dma_handle, int length)
{
	TW_Command *oldcommand;
	TW_Command_Apache *newcommand;
	TW_SG_Entry *sgl;

	if (TW_OP_OUT(full_command_packet->command.newcommand.opcode__reserved) == TW_OP_EXECUTE_SCSI) {
		newcommand = &full_command_packet->command.newcommand;
		newcommand->request_id__lunl = 
			TW_REQ_LUN_IN(TW_LUN_OUT(newcommand->request_id__lunl), request_id);
		newcommand->sg_list[0].address = dma_handle + sizeof(TW_Ioctl_Buf_Apache) - 1;
		newcommand->sg_list[0].length = length;
		newcommand->sgl_entries__lunh =
			TW_REQ_LUN_IN(TW_LUN_OUT(newcommand->sgl_entries__lunh), 1);
	} else {
		oldcommand = &full_command_packet->command.oldcommand;
		oldcommand->request_id = request_id;

		if (TW_SGL_OUT(oldcommand->opcode__sgloffset)) {
			/* Load the sg list */
			sgl = (TW_SG_Entry *)((u32 *)oldcommand+TW_SGL_OUT(oldcommand->opcode__sgloffset));
			sgl->address = dma_handle + sizeof(TW_Ioctl_Buf_Apache) - 1;
			sgl->length = length;

			if ((sizeof(long) < 8) && (sizeof(dma_addr_t) > 4))
				oldcommand->size += 1;
		}
	}
} /* End twa_load_sgl() */

/* This function will perform a pci-dma mapping for a scatter gather list */
static int twa_map_scsi_sg_data(TW_Device_Extension *tw_dev, int request_id)
{
	int use_sg;
	struct scsi_cmnd *cmd = tw_dev->srb[request_id];
	struct pci_dev *pdev = tw_dev->tw_pci_dev;
	int retval = 0;

	if (cmd->use_sg == 0)
		goto out;

	use_sg = pci_map_sg(pdev, cmd->buffer, cmd->use_sg, DMA_BIDIRECTIONAL);

	if (use_sg == 0) {
		TW_PRINTK(tw_dev->host, TW_DRIVER, 0x1c, "Failed to map scatter gather list");
		goto out;
	}

	cmd->SCp.phase = TW_PHASE_SGLIST;
	cmd->SCp.have_data_in = use_sg;
	retval = use_sg;
out:
	return retval;
} /* End twa_map_scsi_sg_data() */

/* This function will perform a pci-dma map for a single buffer */
static dma_addr_t twa_map_scsi_single_data(TW_Device_Extension *tw_dev, int request_id)
{
	dma_addr_t mapping;
	struct scsi_cmnd *cmd = tw_dev->srb[request_id];
	struct pci_dev *pdev = tw_dev->tw_pci_dev;
	int retval = 0;

	if (cmd->request_bufflen == 0) {
		retval = 0;
		goto out;
	}

	mapping = pci_map_single(pdev, cmd->request_buffer, cmd->request_bufflen, DMA_BIDIRECTIONAL);

	if (mapping == 0) {
		TW_PRINTK(tw_dev->host, TW_DRIVER, 0x1d, "Failed to map page");
		goto out;
	}

	cmd->SCp.phase = TW_PHASE_SINGLE;
	cmd->SCp.have_data_in = mapping;
	retval = mapping;
out:
	return retval;
} /* End twa_map_scsi_single_data() */

/* This function will poll for a response interrupt of a request */
static int twa_poll_response(TW_Device_Extension *tw_dev, int request_id, int seconds)
{
	int retval = 1, found = 0, response_request_id;
	TW_Response_Queue response_queue;
	TW_Command_Full *full_command_packet = tw_dev->command_packet_virt[request_id];

	if (twa_poll_status_gone(tw_dev, TW_STATUS_RESPONSE_QUEUE_EMPTY, seconds) == 0) {
		response_queue.value = readl(TW_RESPONSE_QUEUE_REG_ADDR(tw_dev));
		response_request_id = TW_RESID_OUT(response_queue.response_id);
		if (request_id != response_request_id) {
			TW_PRINTK(tw_dev->host, TW_DRIVER, 0x1e, "Found unexpected request id while polling for response");
			goto out;
		}
		if (TW_OP_OUT(full_command_packet->command.newcommand.opcode__reserved) == TW_OP_EXECUTE_SCSI) {
			if (full_command_packet->command.newcommand.status != 0) {
				/* bad response */
				twa_fill_sense(tw_dev, request_id, 0, 0);
				goto out;
			}
			found = 1;
		} else {
			if (full_command_packet->command.oldcommand.status != 0) {
				/* bad response */
				twa_fill_sense(tw_dev, request_id, 0, 0);
				goto out;
			}
			found = 1;
		}
	}

	if (found)
		retval = 0;
out:
	return retval;
} /* End twa_poll_response() */

/* This function will poll the status register for a flag */
static int twa_poll_status(TW_Device_Extension *tw_dev, u32 flag, int seconds)
{
	u32 status_reg_value; 
	unsigned long before;
	int retval = 1;

	status_reg_value = readl(TW_STATUS_REG_ADDR(tw_dev));
	before = jiffies;

	if (twa_check_bits(status_reg_value))
		twa_decode_bits(tw_dev, status_reg_value);

	while ((status_reg_value & flag) != flag) {
		status_reg_value = readl(TW_STATUS_REG_ADDR(tw_dev));

		if (twa_check_bits(status_reg_value))
			twa_decode_bits(tw_dev, status_reg_value);

		if (time_after(jiffies, before + HZ * seconds))
			goto out;

		msleep(50);
	}
	retval = 0;
out:
	return retval;
} /* End twa_poll_status() */

/* This function will poll the status register for disappearance of a flag */
static int twa_poll_status_gone(TW_Device_Extension *tw_dev, u32 flag, int seconds)
{
	u32 status_reg_value;
	unsigned long before;
	int retval = 1;

	status_reg_value = readl(TW_STATUS_REG_ADDR(tw_dev));
	before = jiffies;

	if (twa_check_bits(status_reg_value))
		twa_decode_bits(tw_dev, status_reg_value);

	while ((status_reg_value & flag) != 0) {
		status_reg_value = readl(TW_STATUS_REG_ADDR(tw_dev));
		if (twa_check_bits(status_reg_value))
			twa_decode_bits(tw_dev, status_reg_value);

		if (time_after(jiffies, before + HZ * seconds))
			goto out;

		msleep(50);
	}
	retval = 0;
out:
	return retval;
} /* End twa_poll_status_gone() */

/* This function will attempt to post a command packet to the board */
static int twa_post_command_packet(TW_Device_Extension *tw_dev, int request_id, char internal)
{
	u32 status_reg_value;
	dma_addr_t command_que_value;
	int retval = 1;

	command_que_value = tw_dev->command_packet_phys[request_id];
	status_reg_value = readl(TW_STATUS_REG_ADDR(tw_dev));

	if (twa_check_bits(status_reg_value))
		twa_decode_bits(tw_dev, status_reg_value);

	if (((tw_dev->pending_request_count > 0) && (tw_dev->state[request_id] != TW_S_PENDING)) || (status_reg_value & TW_STATUS_COMMAND_QUEUE_FULL)) {

		/* Only pend internal driver commands */
		if (!internal) {
			retval = SCSI_MLQUEUE_HOST_BUSY;
			goto out;
		}

		/* Couldn't post the command packet, so we do it later */
		if (tw_dev->state[request_id] != TW_S_PENDING) {
			tw_dev->state[request_id] = TW_S_PENDING;
			tw_dev->pending_request_count++;
			if (tw_dev->pending_request_count > tw_dev->max_pending_request_count) {
				tw_dev->max_pending_request_count = tw_dev->pending_request_count;
			}
			tw_dev->pending_queue[tw_dev->pending_tail] = request_id;
			tw_dev->pending_tail = (tw_dev->pending_tail + 1) % TW_Q_LENGTH;
		}
		TW_UNMASK_COMMAND_INTERRUPT(tw_dev);
		goto out;
	} else {
		/* We successfully posted the command packet */
		if (sizeof(dma_addr_t) > 4) {
			command_que_value += TW_COMMAND_OFFSET;
			writel((u32)command_que_value, TW_COMMAND_QUEUE_REG_ADDR(tw_dev));
			writel((u32)((u64)command_que_value >> 32), TW_COMMAND_QUEUE_REG_ADDR(tw_dev) + 0x4);
		} else {
			writel(TW_COMMAND_OFFSET + command_que_value, TW_COMMAND_QUEUE_REG_ADDR(tw_dev));
		}
		tw_dev->state[request_id] = TW_S_POSTED;
		tw_dev->posted_request_count++;
		if (tw_dev->posted_request_count > tw_dev->max_posted_request_count) {
			tw_dev->max_posted_request_count = tw_dev->posted_request_count;
		}
	}
	retval = 0;
out:
	return retval;
} /* End twa_post_command_packet() */

/* This function will reset a device extension */
static int twa_reset_device_extension(TW_Device_Extension *tw_dev, int ioctl_reset)
{
	int i = 0;
	int retval = 1;
	unsigned long flags = 0;

	set_bit(TW_IN_RESET, &tw_dev->flags);
	TW_DISABLE_INTERRUPTS(tw_dev);
	TW_MASK_COMMAND_INTERRUPT(tw_dev);
	spin_lock_irqsave(tw_dev->host->host_lock, flags);

	/* Abort all requests that are in progress */
	for (i = 0; i < TW_Q_LENGTH; i++) {
		if ((tw_dev->state[i] != TW_S_FINISHED) &&
		    (tw_dev->state[i] != TW_S_INITIAL) &&
		    (tw_dev->state[i] != TW_S_COMPLETED)) {
			if (tw_dev->srb[i]) {
				tw_dev->srb[i]->result = (DID_RESET << 16);
				tw_dev->srb[i]->scsi_done(tw_dev->srb[i]);
				twa_unmap_scsi_data(tw_dev, i);
			}
		}
	}

	/* Reset queues and counts */
	for (i = 0; i < TW_Q_LENGTH; i++) {
		tw_dev->free_queue[i] = i;
		tw_dev->state[i] = TW_S_INITIAL;
	}
	tw_dev->free_head = TW_Q_START;
	tw_dev->free_tail = TW_Q_START;
	tw_dev->posted_request_count = 0;
	tw_dev->pending_request_count = 0;
	tw_dev->pending_head = TW_Q_START;
	tw_dev->pending_tail = TW_Q_START;
	tw_dev->reset_print = 0;

	spin_unlock_irqrestore(tw_dev->host->host_lock, flags);

	if (twa_reset_sequence(tw_dev, 1))
		goto out;

	TW_ENABLE_AND_CLEAR_INTERRUPTS(tw_dev);

	/* Wake up any ioctl that was pending before the reset */
	if ((tw_dev->chrdev_request_id == TW_IOCTL_CHRDEV_FREE) || (ioctl_reset)) {
		clear_bit(TW_IN_RESET, &tw_dev->flags);
	} else {
		tw_dev->chrdev_request_id = TW_IOCTL_CHRDEV_FREE;
		wake_up(&tw_dev->ioctl_wqueue);
	}
	retval = 0;
out:
	return retval;
} /* End twa_reset_device_extension() */

/* This function will reset a controller */
static int twa_reset_sequence(TW_Device_Extension *tw_dev, int soft_reset)
{
	int tries = 0, retval = 1, flashed = 0, do_soft_reset = soft_reset;

	while (tries < TW_MAX_RESET_TRIES) {
		if (do_soft_reset)
			TW_SOFT_RESET(tw_dev);

		/* Make sure controller is in a good state */
		if (twa_poll_status(tw_dev, TW_STATUS_MICROCONTROLLER_READY | (do_soft_reset == 1 ? TW_STATUS_ATTENTION_INTERRUPT : 0), 60)) {
			TW_PRINTK(tw_dev->host, TW_DRIVER, 0x1f, "Microcontroller not ready during reset sequence");
			do_soft_reset = 1;
			tries++;
			continue;
		}

		/* Empty response queue */
		if (twa_empty_response_queue(tw_dev)) {
			TW_PRINTK(tw_dev->host, TW_DRIVER, 0x20, "Response queue empty failed during reset sequence");
			do_soft_reset = 1;
			tries++;
			continue;
		}

		flashed = 0;

		/* Check for compatibility/flash */
		if (twa_check_srl(tw_dev, &flashed)) {
			TW_PRINTK(tw_dev->host, TW_DRIVER, 0x21, "Compatibility check failed during reset sequence");
			do_soft_reset = 1;
			tries++;
			continue;
		} else {
			if (flashed) {
				tries++;
				continue;
			}
		}

		/* Drain the AEN queue */
		if (twa_aen_drain_queue(tw_dev, soft_reset)) {
			TW_PRINTK(tw_dev->host, TW_DRIVER, 0x22, "AEN drain failed during reset sequence");
			do_soft_reset = 1;
			tries++;
			continue;
		}

		/* If we got here, controller is in a good state */
		retval = 0;
		goto out;
	}
out:
	return retval;
} /* End twa_reset_sequence() */

/* This funciton returns unit geometry in cylinders/heads/sectors */
static int twa_scsi_biosparam(struct scsi_device *sdev, struct block_device *bdev, sector_t capacity, int geom[])
{
	int heads, sectors, cylinders;
	TW_Device_Extension *tw_dev;

	tw_dev = (TW_Device_Extension *)sdev->host->hostdata;

	if (capacity >= 0x200000) {
		heads = 255;
		sectors = 63;
		cylinders = sector_div(capacity, heads * sectors);
	} else {
		heads = 64;
		sectors = 32;
		cylinders = sector_div(capacity, heads * sectors);
	}

	geom[0] = heads;
	geom[1] = sectors;
	geom[2] = cylinders;

	return 0;
} /* End twa_scsi_biosparam() */

/* This is the new scsi eh reset function */
static int twa_scsi_eh_reset(struct scsi_cmnd *SCpnt)
{
	TW_Device_Extension *tw_dev = NULL;
	int retval = FAILED;

	tw_dev = (TW_Device_Extension *)SCpnt->device->host->hostdata;

	tw_dev->num_resets++;

	printk(KERN_WARNING "3w-9xxx: scsi%d: WARNING: (0x%02X:0x%04X): Unit #%d: Command (0x%x) timed out, resetting card.\n", tw_dev->host->host_no, TW_DRIVER, 0x2c, SCpnt->device->id, SCpnt->cmnd[0]);

	/* Now reset the card and some of the device extension data */
	if (twa_reset_device_extension(tw_dev, 0)) {
		TW_PRINTK(tw_dev->host, TW_DRIVER, 0x2b, "Controller reset failed during scsi host reset");
		goto out;
	}

	retval = SUCCESS;
out:
	return retval;
} /* End twa_scsi_eh_reset() */

/* This is the main scsi queue function to handle scsi opcodes */
static int twa_scsi_queue(struct scsi_cmnd *SCpnt, void (*done)(struct scsi_cmnd *))
{
	int request_id, retval;
	TW_Device_Extension *tw_dev = (TW_Device_Extension *)SCpnt->device->host->hostdata;

	/* Check if this FW supports luns */
	if ((SCpnt->device->lun != 0) && (tw_dev->working_srl < TW_FW_SRL_LUNS_SUPPORTED)) {
		SCpnt->result = (DID_BAD_TARGET << 16);
		done(SCpnt);
		retval = 0;
		goto out;
	}

	/* Save done function into scsi_cmnd struct */
	SCpnt->scsi_done = done;
		
	/* Get a free request id */
	twa_get_request_id(tw_dev, &request_id);

	/* Save the scsi command for use by the ISR */
	tw_dev->srb[request_id] = SCpnt;

	/* Initialize phase to zero */
	SCpnt->SCp.phase = TW_PHASE_INITIAL;

	retval = twa_scsiop_execute_scsi(tw_dev, request_id, NULL, 0, NULL);
	switch (retval) {
	case SCSI_MLQUEUE_HOST_BUSY:
		twa_free_request_id(tw_dev, request_id);
		break;
	case 1:
		tw_dev->state[request_id] = TW_S_COMPLETED;
		twa_free_request_id(tw_dev, request_id);
		SCpnt->result = (DID_ERROR << 16);
		done(SCpnt);
		retval = 0;
	}
out:
	return retval;
} /* End twa_scsi_queue() */

/* This function hands scsi cdb's to the firmware */
static int twa_scsiop_execute_scsi(TW_Device_Extension *tw_dev, int request_id, char *cdb, int use_sg, TW_SG_Entry *sglistarg)
{
	TW_Command_Full *full_command_packet;
	TW_Command_Apache *command_packet;
	u32 num_sectors = 0x0;
	int i, sg_count;
	struct scsi_cmnd *srb = NULL;
	struct scatterlist *sglist = NULL;
	u32 buffaddr = 0x0;
	int retval = 1;

	if (tw_dev->srb[request_id]) {
		if (tw_dev->srb[request_id]->request_buffer) {
			sglist = (struct scatterlist *)tw_dev->srb[request_id]->request_buffer;
		}
		srb = tw_dev->srb[request_id];
	}

	/* Initialize command packet */
	full_command_packet = tw_dev->command_packet_virt[request_id];
	full_command_packet->header.header_desc.size_header = 128;
	full_command_packet->header.status_block.error = 0;
	full_command_packet->header.status_block.severity__reserved = 0;

	command_packet = &full_command_packet->command.newcommand;
	command_packet->status = 0;
	command_packet->opcode__reserved = TW_OPRES_IN(0, TW_OP_EXECUTE_SCSI);

	/* We forced 16 byte cdb use earlier */
	if (!cdb)
		memcpy(command_packet->cdb, srb->cmnd, TW_MAX_CDB_LEN);
	else
		memcpy(command_packet->cdb, cdb, TW_MAX_CDB_LEN);

	if (srb) {
		command_packet->unit = srb->device->id;
		command_packet->request_id__lunl =
			TW_REQ_LUN_IN(srb->device->lun, request_id);
	} else {
		command_packet->request_id__lunl =
			TW_REQ_LUN_IN(0, request_id);
		command_packet->unit = 0;
	}

	command_packet->sgl_offset = 16;

	if (!sglistarg) {
		/* Map sglist from scsi layer to cmd packet */
		if (tw_dev->srb[request_id]->use_sg == 0) {
			if (tw_dev->srb[request_id]->request_bufflen < TW_MIN_SGL_LENGTH) {
				command_packet->sg_list[0].address = tw_dev->generic_buffer_phys[request_id];
				command_packet->sg_list[0].length = TW_MIN_SGL_LENGTH;
			} else {
				buffaddr = twa_map_scsi_single_data(tw_dev, request_id);
				if (buffaddr == 0)
					goto out;

				command_packet->sg_list[0].address = buffaddr;
				command_packet->sg_list[0].length = tw_dev->srb[request_id]->request_bufflen;
			}
			command_packet->sgl_entries__lunh = TW_REQ_LUN_IN((srb->device->lun >> 4), 1);

			if (command_packet->sg_list[0].address & TW_ALIGNMENT_9000_SGL) {
				TW_PRINTK(tw_dev->host, TW_DRIVER, 0x2d, "Found unaligned address during execute scsi");
				goto out;
			}
		}

		if (tw_dev->srb[request_id]->use_sg > 0) {
			if ((tw_dev->srb[request_id]->use_sg == 1) && (tw_dev->srb[request_id]->request_bufflen < TW_MIN_SGL_LENGTH)) {
				command_packet->sg_list[0].address = tw_dev->generic_buffer_phys[request_id];
				command_packet->sg_list[0].length = TW_MIN_SGL_LENGTH;
			} else {
				sg_count = twa_map_scsi_sg_data(tw_dev, request_id);
				if (sg_count == 0)
					goto out;

				for (i = 0; i < sg_count; i++) {
					command_packet->sg_list[i].address = sg_dma_address(&sglist[i]);
					command_packet->sg_list[i].length = sg_dma_len(&sglist[i]);
					if (command_packet->sg_list[i].address & TW_ALIGNMENT_9000_SGL) {
						TW_PRINTK(tw_dev->host, TW_DRIVER, 0x2e, "Found unaligned sgl address during execute scsi");
						goto out;
					}
				}
			}
			command_packet->sgl_entries__lunh = TW_REQ_LUN_IN((srb->device->lun >> 4), tw_dev->srb[request_id]->use_sg);
		}
	} else {
		/* Internal cdb post */
		for (i = 0; i < use_sg; i++) {
			command_packet->sg_list[i].address = sglistarg[i].address;
			command_packet->sg_list[i].length = sglistarg[i].length;
			if (command_packet->sg_list[i].address & TW_ALIGNMENT_9000_SGL) {
				TW_PRINTK(tw_dev->host, TW_DRIVER, 0x2f, "Found unaligned sgl address during internal post");
				goto out;
			}
		}
		command_packet->sgl_entries__lunh = TW_REQ_LUN_IN(0, use_sg);
	}

	if (srb) {
		if (srb->cmnd[0] == READ_6 || srb->cmnd[0] == WRITE_6)
			num_sectors = (u32)srb->cmnd[4];

		if (srb->cmnd[0] == READ_10 || srb->cmnd[0] == WRITE_10)
			num_sectors = (u32)srb->cmnd[8] | ((u32)srb->cmnd[7] << 8);
	}

	/* Update sector statistic */
	tw_dev->sector_count = num_sectors;
	if (tw_dev->sector_count > tw_dev->max_sector_count)
		tw_dev->max_sector_count = tw_dev->sector_count;

	/* Update SG statistics */
	if (srb) {
		tw_dev->sgl_entries = tw_dev->srb[request_id]->use_sg;
		if (tw_dev->sgl_entries > tw_dev->max_sgl_entries)
			tw_dev->max_sgl_entries = tw_dev->sgl_entries;
	}

	/* Now post the command to the board */
	if (srb) {
		retval = twa_post_command_packet(tw_dev, request_id, 0);
	} else {
		twa_post_command_packet(tw_dev, request_id, 1);
		retval = 0;
	}
out:
	return retval;
} /* End twa_scsiop_execute_scsi() */

/* This function completes an execute scsi operation */
static void twa_scsiop_execute_scsi_complete(TW_Device_Extension *tw_dev, int request_id)
{
	/* Copy the response if too small */
	if ((tw_dev->srb[request_id]->request_buffer) && (tw_dev->srb[request_id]->request_bufflen < TW_MIN_SGL_LENGTH)) {
		memcpy(tw_dev->srb[request_id]->request_buffer,
		       tw_dev->generic_buffer_virt[request_id],
		       tw_dev->srb[request_id]->request_bufflen);
	}
} /* End twa_scsiop_execute_scsi_complete() */

/* This function tells the controller to shut down */
static void __twa_shutdown(TW_Device_Extension *tw_dev)
{
	/* Disable interrupts */
	TW_DISABLE_INTERRUPTS(tw_dev);

	printk(KERN_WARNING "3w-9xxx: Shutting down host %d.\n", tw_dev->host->host_no);

	/* Tell the card we are shutting down */
	if (twa_initconnection(tw_dev, 1, 0, 0, 0, 0, 0, NULL, NULL, NULL, NULL, NULL)) {
		TW_PRINTK(tw_dev->host, TW_DRIVER, 0x31, "Connection shutdown failed");
	} else {
		printk(KERN_WARNING "3w-9xxx: Shutdown complete.\n");
	}

	/* Clear all interrupts just before exit */
	TW_CLEAR_ALL_INTERRUPTS(tw_dev);
} /* End __twa_shutdown() */

/* Wrapper for __twa_shutdown */
static void twa_shutdown(struct device *dev)
{
	struct Scsi_Host *host = pci_get_drvdata(to_pci_dev(dev));
	TW_Device_Extension *tw_dev = (TW_Device_Extension *)host->hostdata;

	__twa_shutdown(tw_dev);
} /* End twa_shutdown() */

/* This function will look up a string */
static char *twa_string_lookup(twa_message_type *table, unsigned int code)
{
	int index;

	for (index = 0; ((code != table[index].code) &&
		      (table[index].text != (char *)0)); index++);
	return(table[index].text);
} /* End twa_string_lookup() */

/* This function will perform a pci-dma unmap */
static void twa_unmap_scsi_data(TW_Device_Extension *tw_dev, int request_id)
{
	struct scsi_cmnd *cmd = tw_dev->srb[request_id];
	struct pci_dev *pdev = tw_dev->tw_pci_dev;

	switch(cmd->SCp.phase) {
	case TW_PHASE_SINGLE:
		pci_unmap_single(pdev, cmd->SCp.have_data_in, cmd->request_bufflen, DMA_BIDIRECTIONAL);
		break;
	case TW_PHASE_SGLIST:
		pci_unmap_sg(pdev, cmd->request_buffer, cmd->use_sg, DMA_BIDIRECTIONAL);
		break;
	}
} /* End twa_unmap_scsi_data() */

/* scsi_host_template initializer */
static struct scsi_host_template driver_template = {
	.module			= THIS_MODULE,
	.name			= "3ware 9000 Storage Controller",
	.queuecommand		= twa_scsi_queue,
	.eh_host_reset_handler	= twa_scsi_eh_reset,
	.bios_param		= twa_scsi_biosparam,
	.change_queue_depth	= twa_change_queue_depth,
	.can_queue		= TW_Q_LENGTH-2,
	.this_id		= -1,
	.sg_tablesize		= TW_APACHE_MAX_SGL_LENGTH,
	.max_sectors		= TW_MAX_SECTORS,
	.cmd_per_lun		= TW_MAX_CMDS_PER_LUN,
	.use_clustering		= ENABLE_CLUSTERING,
	.shost_attrs		= twa_host_attrs,
	.emulated		= 1
};

/* This function will probe and initialize a card */
static int __devinit twa_probe(struct pci_dev *pdev, const struct pci_device_id *dev_id)
{
	struct Scsi_Host *host = NULL;
	TW_Device_Extension *tw_dev;
	u32 mem_addr;
	int retval = -ENODEV;

	retval = pci_enable_device(pdev);
	if (retval) {
		TW_PRINTK(host, TW_DRIVER, 0x34, "Failed to enable pci device");
		goto out_disable_device;
	}

	pci_set_master(pdev);

	retval = pci_set_dma_mask(pdev, sizeof(dma_addr_t) > 4 ? DMA_64BIT_MASK : DMA_32BIT_MASK);
	if (retval) {
		TW_PRINTK(host, TW_DRIVER, 0x23, "Failed to set dma mask");
		goto out_disable_device;
	}

	host = scsi_host_alloc(&driver_template, sizeof(TW_Device_Extension));
	if (!host) {
		TW_PRINTK(host, TW_DRIVER, 0x24, "Failed to allocate memory for device extension");
		retval = -ENOMEM;
		goto out_disable_device;
	}
	tw_dev = (TW_Device_Extension *)host->hostdata;

	memset(tw_dev, 0, sizeof(TW_Device_Extension));

	/* Save values to device extension */
	tw_dev->host = host;
	tw_dev->tw_pci_dev = pdev;

	if (twa_initialize_device_extension(tw_dev)) {
		TW_PRINTK(tw_dev->host, TW_DRIVER, 0x25, "Failed to initialize device extension");
		goto out_free_device_extension;
	}

	/* Request IO regions */
	retval = pci_request_regions(pdev, "3w-9xxx");
	if (retval) {
		TW_PRINTK(tw_dev->host, TW_DRIVER, 0x26, "Failed to get mem region");
		goto out_free_device_extension;
	}

	mem_addr = pci_resource_start(pdev, 1);

	/* Save base address */
	tw_dev->base_addr = ioremap(mem_addr, PAGE_SIZE);
	if (!tw_dev->base_addr) {
		TW_PRINTK(tw_dev->host, TW_DRIVER, 0x35, "Failed to ioremap");
		goto out_release_mem_region;
	}

	/* Disable interrupts on the card */
	TW_DISABLE_INTERRUPTS(tw_dev);

	/* Initialize the card */
	if (twa_reset_sequence(tw_dev, 0))
		goto out_release_mem_region;

	/* Set host specific parameters */
	host->max_id = TW_MAX_UNITS;
	host->max_cmd_len = TW_MAX_CDB_LEN;

	/* Channels aren't supported by adapter */
	host->max_lun = TW_MAX_LUNS(tw_dev->working_srl);
	host->max_channel = 0;

	/* Register the card with the kernel SCSI layer */
	retval = scsi_add_host(host, &pdev->dev);
	if (retval) {
		TW_PRINTK(tw_dev->host, TW_DRIVER, 0x27, "scsi add host failed");
		goto out_release_mem_region;
	}

	pci_set_drvdata(pdev, host);

	printk(KERN_WARNING "3w-9xxx: scsi%d: Found a 3ware 9000 Storage Controller at 0x%x, IRQ: %d.\n",
	       host->host_no, mem_addr, pdev->irq);
	printk(KERN_WARNING "3w-9xxx: scsi%d: Firmware %s, BIOS %s, Ports: %d.\n",
	       host->host_no,
	       (char *)twa_get_param(tw_dev, 0, TW_VERSION_TABLE,
				     TW_PARAM_FWVER, TW_PARAM_FWVER_LENGTH),
	       (char *)twa_get_param(tw_dev, 1, TW_VERSION_TABLE,
				     TW_PARAM_BIOSVER, TW_PARAM_BIOSVER_LENGTH),
	       *(int *)twa_get_param(tw_dev, 2, TW_INFORMATION_TABLE,
				     TW_PARAM_PORTCOUNT, TW_PARAM_PORTCOUNT_LENGTH));

	/* Now setup the interrupt handler */
	retval = request_irq(pdev->irq, twa_interrupt, SA_SHIRQ, "3w-9xxx", tw_dev);
	if (retval) {
		TW_PRINTK(tw_dev->host, TW_DRIVER, 0x30, "Error requesting IRQ");
		goto out_remove_host;
	}

	twa_device_extension_list[twa_device_extension_count] = tw_dev;
	twa_device_extension_count++;

	/* Re-enable interrupts on the card */
	TW_ENABLE_AND_CLEAR_INTERRUPTS(tw_dev);

	/* Finally, scan the host */
	scsi_scan_host(host);

	if (twa_major == -1) {
		if ((twa_major = register_chrdev (0, "twa", &twa_fops)) < 0)
			TW_PRINTK(host, TW_DRIVER, 0x29, "Failed to register character device");
	}
	return 0;

out_remove_host:
	scsi_remove_host(host);
out_release_mem_region:
	pci_release_regions(pdev);
out_free_device_extension:
	twa_free_device_extension(tw_dev);
	scsi_host_put(host);
out_disable_device:
	pci_disable_device(pdev);

	return retval;
} /* End twa_probe() */

/* This function is called to remove a device */
static void twa_remove(struct pci_dev *pdev)
{
	struct Scsi_Host *host = pci_get_drvdata(pdev);
	TW_Device_Extension *tw_dev = (TW_Device_Extension *)host->hostdata;

	scsi_remove_host(tw_dev->host);

	/* Unregister character device */
	if (twa_major >= 0) {
		unregister_chrdev(twa_major, "twa");
		twa_major = -1;
	}

	/* Free up the IRQ */
	free_irq(tw_dev->tw_pci_dev->irq, tw_dev);

	/* Shutdown the card */
	__twa_shutdown(tw_dev);

	/* Free up the mem region */
	pci_release_regions(pdev);

	/* Free up device extension resources */
	twa_free_device_extension(tw_dev);

	scsi_host_put(tw_dev->host);
	pci_disable_device(pdev);
	twa_device_extension_count--;
} /* End twa_remove() */

/* PCI Devices supported by this driver */
static struct pci_device_id twa_pci_tbl[] __devinitdata = {
	{ PCI_VENDOR_ID_3WARE, PCI_DEVICE_ID_3WARE_9000,
	  PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},
	{ }
};
MODULE_DEVICE_TABLE(pci, twa_pci_tbl);

/* pci_driver initializer */
static struct pci_driver twa_driver = {
	.name		= "3w-9xxx",
	.id_table	= twa_pci_tbl,
	.probe		= twa_probe,
	.remove		= twa_remove,
	.driver		= {
		.shutdown = twa_shutdown
	}
};

/* This function is called on driver initialization */
static int __init twa_init(void)
{
	printk(KERN_WARNING "3ware 9000 Storage Controller device driver for Linux v%s.\n", TW_DRIVER_VERSION);

	return pci_module_init(&twa_driver);
} /* End twa_init() */

/* This function is called on driver exit */
static void __exit twa_exit(void)
{
	pci_unregister_driver(&twa_driver);
} /* End twa_exit() */

module_init(twa_init);
module_exit(twa_exit);