drivers/scsi/qla4xxx/ql4_iocb.c - arm/linux-arm64-legacy - Git at Google

 /*
  * QLogic iSCSI HBA Driver
  * Copyright (c)  2003-2006 QLogic Corporation
  *
  * See LICENSE.qla4xxx for copyright and licensing details.
  */

 #include "ql4_def.h"
 #include "ql4_glbl.h"
 #include "ql4_dbg.h"
 #include "ql4_inline.h"

 #include <scsi/scsi_tcq.h>

 static int
 qla4xxx_space_in_req_ring(struct scsi_qla_host *ha, uint16_t req_cnt)
 {
 	uint16_t cnt;

 	/* Calculate number of free request entries. */
 	if ((req_cnt + 2) >= ha->req_q_count) {
 		cnt = (uint16_t) ha->isp_ops->rd_shdw_req_q_out(ha);
 		if (ha->request_in < cnt)
 			ha->req_q_count = cnt - ha->request_in;
 		else
 			ha->req_q_count = REQUEST_QUEUE_DEPTH -
 						(ha->request_in - cnt);
 	}

 	/* Check if room for request in request ring. */
 	if ((req_cnt + 2) < ha->req_q_count)
 		return 1;
 	else
 		return 0;
 }

 static void qla4xxx_advance_req_ring_ptr(struct scsi_qla_host *ha)
 {
 	/* Advance request queue pointer */
 	if (ha->request_in == (REQUEST_QUEUE_DEPTH - 1)) {
 		ha->request_in = 0;
 		ha->request_ptr = ha->request_ring;
 	} else {
 		ha->request_in++;
 		ha->request_ptr++;
 	}
 }

 /**
  * qla4xxx_get_req_pkt - returns a valid entry in request queue.
  * @ha: Pointer to host adapter structure.
  * @queue_entry: Pointer to pointer to queue entry structure
  *
  * This routine performs the following tasks:
  *	- returns the current request_in pointer (if queue not full)
  *	- advances the request_in pointer
  *	- checks for queue full
  **/
 static int qla4xxx_get_req_pkt(struct scsi_qla_host *ha,
 			       struct queue_entry **queue_entry)
 {
 	uint16_t req_cnt = 1;

 	if (qla4xxx_space_in_req_ring(ha, req_cnt)) {
 		*queue_entry = ha->request_ptr;
 		memset(*queue_entry, 0, sizeof(**queue_entry));

 		qla4xxx_advance_req_ring_ptr(ha);
 		ha->req_q_count -= req_cnt;
 		return QLA_SUCCESS;
 	}

 	return QLA_ERROR;
 }

 /**
  * qla4xxx_send_marker_iocb - issues marker iocb to HBA
  * @ha: Pointer to host adapter structure.
  * @ddb_entry: Pointer to device database entry
  * @lun: SCSI LUN
  * @marker_type: marker identifier
  *
  * This routine issues a marker IOCB.
  **/
 int qla4xxx_send_marker_iocb(struct scsi_qla_host *ha,
 	struct ddb_entry *ddb_entry, int lun, uint16_t mrkr_mod)
 {
 	struct qla4_marker_entry *marker_entry;
 	unsigned long flags = 0;
 	uint8_t status = QLA_SUCCESS;

 	/* Acquire hardware specific lock */
 	spin_lock_irqsave(&ha->hardware_lock, flags);

 	/* Get pointer to the queue entry for the marker */
 	if (qla4xxx_get_req_pkt(ha, (struct queue_entry **) &marker_entry) !=
 	    QLA_SUCCESS) {
 		status = QLA_ERROR;
 		goto exit_send_marker;
 	}

 	/* Put the marker in the request queue */
 	marker_entry->hdr.entryType = ET_MARKER;
 	marker_entry->hdr.entryCount = 1;
 	marker_entry->target = cpu_to_le16(ddb_entry->fw_ddb_index);
 	marker_entry->modifier = cpu_to_le16(mrkr_mod);
 	int_to_scsilun(lun, &marker_entry->lun);
 	wmb();

 	/* Tell ISP it's got a new I/O request */
 	ha->isp_ops->queue_iocb(ha);

 exit_send_marker:
 	spin_unlock_irqrestore(&ha->hardware_lock, flags);
 	return status;
 }

 static struct continuation_t1_entry *
 qla4xxx_alloc_cont_entry(struct scsi_qla_host *ha)
 {
 	struct continuation_t1_entry *cont_entry;

 	cont_entry = (struct continuation_t1_entry *)ha->request_ptr;

 	qla4xxx_advance_req_ring_ptr(ha);

 	/* Load packet defaults */
 	cont_entry->hdr.entryType = ET_CONTINUE;
 	cont_entry->hdr.entryCount = 1;
 	cont_entry->hdr.systemDefined = (uint8_t) cpu_to_le16(ha->request_in);

 	return cont_entry;
 }

 static uint16_t qla4xxx_calc_request_entries(uint16_t dsds)
 {
 	uint16_t iocbs;

 	iocbs = 1;
 	if (dsds > COMMAND_SEG) {
 		iocbs += (dsds - COMMAND_SEG) / CONTINUE_SEG;
 		if ((dsds - COMMAND_SEG) % CONTINUE_SEG)
 			iocbs++;
 	}
 	return iocbs;
 }

 static void qla4xxx_build_scsi_iocbs(struct srb *srb,
 				     struct command_t3_entry *cmd_entry,
 				     uint16_t tot_dsds)
 {
 	struct scsi_qla_host *ha;
 	uint16_t avail_dsds;
 	struct data_seg_a64 *cur_dsd;
 	struct scsi_cmnd *cmd;
 	struct scatterlist *sg;
 	int i;

 	cmd = srb->cmd;
 	ha = srb->ha;

 	if (!scsi_bufflen(cmd) || cmd->sc_data_direction == DMA_NONE) {
 		/* No data being transferred */
 		cmd_entry->ttlByteCnt = __constant_cpu_to_le32(0);
 		return;
 	}

 	avail_dsds = COMMAND_SEG;
 	cur_dsd = (struct data_seg_a64 *) & (cmd_entry->dataseg[0]);

 	scsi_for_each_sg(cmd, sg, tot_dsds, i) {
 		dma_addr_t sle_dma;

 		/* Allocate additional continuation packets? */
 		if (avail_dsds == 0) {
 			struct continuation_t1_entry *cont_entry;

 			cont_entry = qla4xxx_alloc_cont_entry(ha);
 			cur_dsd =
 				(struct data_seg_a64 *)
 				&cont_entry->dataseg[0];
 			avail_dsds = CONTINUE_SEG;
 		}

 		sle_dma = sg_dma_address(sg);
 		cur_dsd->base.addrLow = cpu_to_le32(LSDW(sle_dma));
 		cur_dsd->base.addrHigh = cpu_to_le32(MSDW(sle_dma));
 		cur_dsd->count = cpu_to_le32(sg_dma_len(sg));
 		avail_dsds--;

 		cur_dsd++;
 	}
 }

 /**
  * qla4_8xxx_queue_iocb - Tell ISP it's got new request(s)
  * @ha: pointer to host adapter structure.
  *
  * This routine notifies the ISP that one or more new request
  * queue entries have been placed on the request queue.
  **/
 void qla4_8xxx_queue_iocb(struct scsi_qla_host *ha)
 {
 	uint32_t dbval = 0;

 	dbval = 0x14 | (ha->func_num << 5);
 	dbval = dbval | (0 << 8) | (ha->request_in << 16);

 	qla4_8xxx_wr_32(ha, ha->nx_db_wr_ptr, ha->request_in);
 }

 /**
  * qla4_8xxx_complete_iocb - Tell ISP we're done with response(s)
  * @ha: pointer to host adapter structure.
  *
  * This routine notifies the ISP that one or more response/completion
  * queue entries have been processed by the driver.
  * This also clears the interrupt.
  **/
 void qla4_8xxx_complete_iocb(struct scsi_qla_host *ha)
 {
 	writel(ha->response_out, &ha->qla4_8xxx_reg->rsp_q_out);
 	readl(&ha->qla4_8xxx_reg->rsp_q_out);
 }

 /**
  * qla4xxx_queue_iocb - Tell ISP it's got new request(s)
  * @ha: pointer to host adapter structure.
  *
  * This routine is notifies the ISP that one or more new request
  * queue entries have been placed on the request queue.
  **/
 void qla4xxx_queue_iocb(struct scsi_qla_host *ha)
 {
 	writel(ha->request_in, &ha->reg->req_q_in);
 	readl(&ha->reg->req_q_in);
 }

 /**
  * qla4xxx_complete_iocb - Tell ISP we're done with response(s)
  * @ha: pointer to host adapter structure.
  *
  * This routine is notifies the ISP that one or more response/completion
  * queue entries have been processed by the driver.
  * This also clears the interrupt.
  **/
 void qla4xxx_complete_iocb(struct scsi_qla_host *ha)
 {
 	writel(ha->response_out, &ha->reg->rsp_q_out);
 	readl(&ha->reg->rsp_q_out);
 }

 /**
  * qla4xxx_send_command_to_isp - issues command to HBA
  * @ha: pointer to host adapter structure.
  * @srb: pointer to SCSI Request Block to be sent to ISP
  *
  * This routine is called by qla4xxx_queuecommand to build an ISP
  * command and pass it to the ISP for execution.
  **/
 int qla4xxx_send_command_to_isp(struct scsi_qla_host *ha, struct srb * srb)
 {
 	struct scsi_cmnd *cmd = srb->cmd;
 	struct ddb_entry *ddb_entry;
 	struct command_t3_entry *cmd_entry;
 	int nseg;
 	uint16_t tot_dsds;
 	uint16_t req_cnt;
 	unsigned long flags;
 	uint32_t index;
 	char tag[2];

 	/* Get real lun and adapter */
 	ddb_entry = srb->ddb;

 	tot_dsds = 0;

 	/* Acquire hardware specific lock */
 	spin_lock_irqsave(&ha->hardware_lock, flags);

 	index = (uint32_t)cmd->request->tag;

 	/*
 	 * Check to see if adapter is online before placing request on
 	 * request queue.  If a reset occurs and a request is in the queue,
 	 * the firmware will still attempt to process the request, retrieving
 	 * garbage for pointers.
 	 */
 	if (!test_bit(AF_ONLINE, &ha->flags)) {
 		DEBUG2(printk("scsi%ld: %s: Adapter OFFLINE! "
 			      "Do not issue command.\n",
 			      ha->host_no, __func__));
 		goto queuing_error;
 	}

 	/* Calculate the number of request entries needed. */
 	nseg = scsi_dma_map(cmd);
 	if (nseg < 0)
 		goto queuing_error;
 	tot_dsds = nseg;

 	req_cnt = qla4xxx_calc_request_entries(tot_dsds);
 	if (!qla4xxx_space_in_req_ring(ha, req_cnt))
 		goto queuing_error;

 	/* total iocbs active */
 	if ((ha->iocb_cnt + req_cnt) >= REQUEST_QUEUE_DEPTH)
 		goto queuing_error;

 	/* Build command packet */
 	cmd_entry = (struct command_t3_entry *) ha->request_ptr;
 	memset(cmd_entry, 0, sizeof(struct command_t3_entry));
 	cmd_entry->hdr.entryType = ET_COMMAND;
 	cmd_entry->handle = cpu_to_le32(index);
 	cmd_entry->target = cpu_to_le16(ddb_entry->fw_ddb_index);
 	cmd_entry->connection_id = cpu_to_le16(ddb_entry->connection_id);

 	int_to_scsilun(cmd->device->lun, &cmd_entry->lun);
 	cmd_entry->cmdSeqNum = cpu_to_le32(ddb_entry->CmdSn);
 	cmd_entry->ttlByteCnt = cpu_to_le32(scsi_bufflen(cmd));
 	memcpy(cmd_entry->cdb, cmd->cmnd, cmd->cmd_len);
 	cmd_entry->dataSegCnt = cpu_to_le16(tot_dsds);
 	cmd_entry->hdr.entryCount = req_cnt;

 	/* Set data transfer direction control flags
 	 * NOTE: Look at data_direction bits iff there is data to be
 	 *	 transferred, as the data direction bit is sometimed filled
 	 *	 in when there is no data to be transferred */
 	cmd_entry->control_flags = CF_NO_DATA;
 	if (scsi_bufflen(cmd)) {
 		if (cmd->sc_data_direction == DMA_TO_DEVICE)
 			cmd_entry->control_flags = CF_WRITE;
 		else if (cmd->sc_data_direction == DMA_FROM_DEVICE)
 			cmd_entry->control_flags = CF_READ;

 		ha->bytes_xfered += scsi_bufflen(cmd);
 		if (ha->bytes_xfered & ~0xFFFFF){
 			ha->total_mbytes_xferred += ha->bytes_xfered >> 20;
 			ha->bytes_xfered &= 0xFFFFF;
 		}
 	}

 	/* Set tagged queueing control flags */
 	cmd_entry->control_flags |= CF_SIMPLE_TAG;
 	if (scsi_populate_tag_msg(cmd, tag))
 		switch (tag[0]) {
 		case MSG_HEAD_TAG:
 			cmd_entry->control_flags |= CF_HEAD_TAG;
 			break;
 		case MSG_ORDERED_TAG:
 			cmd_entry->control_flags |= CF_ORDERED_TAG;
 			break;
 		}

 	qla4xxx_advance_req_ring_ptr(ha);
 	qla4xxx_build_scsi_iocbs(srb, cmd_entry, tot_dsds);
 	wmb();

 	srb->cmd->host_scribble = (unsigned char *)(unsigned long)index;

 	/* update counters */
 	srb->state = SRB_ACTIVE_STATE;
 	srb->flags |= SRB_DMA_VALID;

 	/* Track IOCB used */
 	ha->iocb_cnt += req_cnt;
 	srb->iocb_cnt = req_cnt;
 	ha->req_q_count -= req_cnt;

 	ha->isp_ops->queue_iocb(ha);
 	spin_unlock_irqrestore(&ha->hardware_lock, flags);

 	return QLA_SUCCESS;

 queuing_error:
 	if (tot_dsds)
 		scsi_dma_unmap(cmd);

 	spin_unlock_irqrestore(&ha->hardware_lock, flags);

 	return QLA_ERROR;
 }
	/*
	* QLogic iSCSI HBA Driver
	* Copyright (c) 2003-2006 QLogic Corporation
	*
	* See LICENSE.qla4xxx for copyright and licensing details.
	*/

	#include "ql4_def.h"
	#include "ql4_glbl.h"
	#include "ql4_dbg.h"
	#include "ql4_inline.h"

	#include <scsi/scsi_tcq.h>

	static int
	qla4xxx_space_in_req_ring(struct scsi_qla_host *ha, uint16_t req_cnt)
	{
	uint16_t cnt;

	/* Calculate number of free request entries. */
	if ((req_cnt + 2) >= ha->req_q_count) {
	cnt = (uint16_t) ha->isp_ops->rd_shdw_req_q_out(ha);
	if (ha->request_in < cnt)
	ha->req_q_count = cnt - ha->request_in;
	else
	ha->req_q_count = REQUEST_QUEUE_DEPTH -
	(ha->request_in - cnt);
	}

	/* Check if room for request in request ring. */
	if ((req_cnt + 2) < ha->req_q_count)
	return 1;
	else
	return 0;
	}

	static void qla4xxx_advance_req_ring_ptr(struct scsi_qla_host *ha)
	{
	/* Advance request queue pointer */
	if (ha->request_in == (REQUEST_QUEUE_DEPTH - 1)) {
	ha->request_in = 0;
	ha->request_ptr = ha->request_ring;
	} else {
	ha->request_in++;
	ha->request_ptr++;
	}
	}

	/**
	* qla4xxx_get_req_pkt - returns a valid entry in request queue.
	* @ha: Pointer to host adapter structure.
	* @queue_entry: Pointer to pointer to queue entry structure
	*
	* This routine performs the following tasks:
	* - returns the current request_in pointer (if queue not full)
	* - advances the request_in pointer
	* - checks for queue full
	**/
	static int qla4xxx_get_req_pkt(struct scsi_qla_host *ha,
	struct queue_entry **queue_entry)
	{
	uint16_t req_cnt = 1;

	if (qla4xxx_space_in_req_ring(ha, req_cnt)) {
	*queue_entry = ha->request_ptr;
	memset(queue_entry, 0, sizeof(*queue_entry));

	qla4xxx_advance_req_ring_ptr(ha);
	ha->req_q_count -= req_cnt;
	return QLA_SUCCESS;
	}

	return QLA_ERROR;
	}

	/**
	* qla4xxx_send_marker_iocb - issues marker iocb to HBA
	* @ha: Pointer to host adapter structure.
	* @ddb_entry: Pointer to device database entry
	* @lun: SCSI LUN
	* @marker_type: marker identifier
	*
	* This routine issues a marker IOCB.
	**/
	int qla4xxx_send_marker_iocb(struct scsi_qla_host *ha,
	struct ddb_entry *ddb_entry, int lun, uint16_t mrkr_mod)
	{
	struct qla4_marker_entry *marker_entry;
	unsigned long flags = 0;
	uint8_t status = QLA_SUCCESS;

	/* Acquire hardware specific lock */
	spin_lock_irqsave(&ha->hardware_lock, flags);

	/* Get pointer to the queue entry for the marker */
	if (qla4xxx_get_req_pkt(ha, (struct queue_entry **) &marker_entry) !=
	QLA_SUCCESS) {
	status = QLA_ERROR;
	goto exit_send_marker;
	}

	/* Put the marker in the request queue */
	marker_entry->hdr.entryType = ET_MARKER;
	marker_entry->hdr.entryCount = 1;
	marker_entry->target = cpu_to_le16(ddb_entry->fw_ddb_index);
	marker_entry->modifier = cpu_to_le16(mrkr_mod);
	int_to_scsilun(lun, &marker_entry->lun);
	wmb();

	/* Tell ISP it's got a new I/O request */
	ha->isp_ops->queue_iocb(ha);

	exit_send_marker:
	spin_unlock_irqrestore(&ha->hardware_lock, flags);
	return status;
	}

	static struct continuation_t1_entry *
	qla4xxx_alloc_cont_entry(struct scsi_qla_host *ha)
	{
	struct continuation_t1_entry *cont_entry;

	cont_entry = (struct continuation_t1_entry *)ha->request_ptr;

	qla4xxx_advance_req_ring_ptr(ha);

	/* Load packet defaults */
	cont_entry->hdr.entryType = ET_CONTINUE;
	cont_entry->hdr.entryCount = 1;
	cont_entry->hdr.systemDefined = (uint8_t) cpu_to_le16(ha->request_in);

	return cont_entry;
	}

	static uint16_t qla4xxx_calc_request_entries(uint16_t dsds)
	{
	uint16_t iocbs;

	iocbs = 1;
	if (dsds > COMMAND_SEG) {
	iocbs += (dsds - COMMAND_SEG) / CONTINUE_SEG;
	if ((dsds - COMMAND_SEG) % CONTINUE_SEG)
	iocbs++;
	}
	return iocbs;
	}

	static void qla4xxx_build_scsi_iocbs(struct srb *srb,
	struct command_t3_entry *cmd_entry,
	uint16_t tot_dsds)
	{
	struct scsi_qla_host *ha;
	uint16_t avail_dsds;
	struct data_seg_a64 *cur_dsd;
	struct scsi_cmnd *cmd;
	struct scatterlist *sg;
	int i;

	cmd = srb->cmd;
	ha = srb->ha;

	if (!scsi_bufflen(cmd) \|\| cmd->sc_data_direction == DMA_NONE) {
	/* No data being transferred */
	cmd_entry->ttlByteCnt = __constant_cpu_to_le32(0);
	return;
	}

	avail_dsds = COMMAND_SEG;
	cur_dsd = (struct data_seg_a64 *) & (cmd_entry->dataseg[0]);

	scsi_for_each_sg(cmd, sg, tot_dsds, i) {
	dma_addr_t sle_dma;

	/* Allocate additional continuation packets? */
	if (avail_dsds == 0) {
	struct continuation_t1_entry *cont_entry;

	cont_entry = qla4xxx_alloc_cont_entry(ha);
	cur_dsd =
	(struct data_seg_a64 *)
	&cont_entry->dataseg[0];
	avail_dsds = CONTINUE_SEG;
	}

	sle_dma = sg_dma_address(sg);
	cur_dsd->base.addrLow = cpu_to_le32(LSDW(sle_dma));
	cur_dsd->base.addrHigh = cpu_to_le32(MSDW(sle_dma));
	cur_dsd->count = cpu_to_le32(sg_dma_len(sg));
	avail_dsds--;

	cur_dsd++;
	}
	}

	/**
	* qla4_8xxx_queue_iocb - Tell ISP it's got new request(s)
	* @ha: pointer to host adapter structure.
	*
	* This routine notifies the ISP that one or more new request
	* queue entries have been placed on the request queue.
	**/
	void qla4_8xxx_queue_iocb(struct scsi_qla_host *ha)
	{
	uint32_t dbval = 0;

	dbval = 0x14 \| (ha->func_num << 5);
	dbval = dbval \| (0 << 8) \| (ha->request_in << 16);

	qla4_8xxx_wr_32(ha, ha->nx_db_wr_ptr, ha->request_in);
	}

	/**
	* qla4_8xxx_complete_iocb - Tell ISP we're done with response(s)
	* @ha: pointer to host adapter structure.
	*
	* This routine notifies the ISP that one or more response/completion
	* queue entries have been processed by the driver.
	* This also clears the interrupt.
	**/
	void qla4_8xxx_complete_iocb(struct scsi_qla_host *ha)
	{
	writel(ha->response_out, &ha->qla4_8xxx_reg->rsp_q_out);
	readl(&ha->qla4_8xxx_reg->rsp_q_out);
	}

	/**
	* qla4xxx_queue_iocb - Tell ISP it's got new request(s)
	* @ha: pointer to host adapter structure.
	*
	* This routine is notifies the ISP that one or more new request
	* queue entries have been placed on the request queue.
	**/
	void qla4xxx_queue_iocb(struct scsi_qla_host *ha)
	{
	writel(ha->request_in, &ha->reg->req_q_in);
	readl(&ha->reg->req_q_in);
	}

	/**
	* qla4xxx_complete_iocb - Tell ISP we're done with response(s)
	* @ha: pointer to host adapter structure.
	*
	* This routine is notifies the ISP that one or more response/completion
	* queue entries have been processed by the driver.
	* This also clears the interrupt.
	**/
	void qla4xxx_complete_iocb(struct scsi_qla_host *ha)
	{
	writel(ha->response_out, &ha->reg->rsp_q_out);
	readl(&ha->reg->rsp_q_out);
	}

	/**
	* qla4xxx_send_command_to_isp - issues command to HBA
	* @ha: pointer to host adapter structure.
	* @srb: pointer to SCSI Request Block to be sent to ISP
	*
	* This routine is called by qla4xxx_queuecommand to build an ISP
	* command and pass it to the ISP for execution.
	**/
	int qla4xxx_send_command_to_isp(struct scsi_qla_host ha, struct srb srb)
	{
	struct scsi_cmnd *cmd = srb->cmd;
	struct ddb_entry *ddb_entry;
	struct command_t3_entry *cmd_entry;
	int nseg;
	uint16_t tot_dsds;
	uint16_t req_cnt;
	unsigned long flags;
	uint32_t index;
	char tag[2];

	/* Get real lun and adapter */
	ddb_entry = srb->ddb;

	tot_dsds = 0;

	/* Acquire hardware specific lock */
	spin_lock_irqsave(&ha->hardware_lock, flags);

	index = (uint32_t)cmd->request->tag;

	/*
	* Check to see if adapter is online before placing request on
	* request queue. If a reset occurs and a request is in the queue,
	* the firmware will still attempt to process the request, retrieving
	* garbage for pointers.
	*/
	if (!test_bit(AF_ONLINE, &ha->flags)) {
	DEBUG2(printk("scsi%ld: %s: Adapter OFFLINE! "
	"Do not issue command.\n",
	ha->host_no, __func__));
	goto queuing_error;
	}

	/* Calculate the number of request entries needed. */
	nseg = scsi_dma_map(cmd);
	if (nseg < 0)
	goto queuing_error;
	tot_dsds = nseg;

	req_cnt = qla4xxx_calc_request_entries(tot_dsds);
	if (!qla4xxx_space_in_req_ring(ha, req_cnt))
	goto queuing_error;

	/* total iocbs active */
	if ((ha->iocb_cnt + req_cnt) >= REQUEST_QUEUE_DEPTH)
	goto queuing_error;

	/* Build command packet */
	cmd_entry = (struct command_t3_entry *) ha->request_ptr;
	memset(cmd_entry, 0, sizeof(struct command_t3_entry));
	cmd_entry->hdr.entryType = ET_COMMAND;
	cmd_entry->handle = cpu_to_le32(index);
	cmd_entry->target = cpu_to_le16(ddb_entry->fw_ddb_index);
	cmd_entry->connection_id = cpu_to_le16(ddb_entry->connection_id);

	int_to_scsilun(cmd->device->lun, &cmd_entry->lun);
	cmd_entry->cmdSeqNum = cpu_to_le32(ddb_entry->CmdSn);
	cmd_entry->ttlByteCnt = cpu_to_le32(scsi_bufflen(cmd));
	memcpy(cmd_entry->cdb, cmd->cmnd, cmd->cmd_len);
	cmd_entry->dataSegCnt = cpu_to_le16(tot_dsds);
	cmd_entry->hdr.entryCount = req_cnt;

	/* Set data transfer direction control flags
	* NOTE: Look at data_direction bits iff there is data to be
	* transferred, as the data direction bit is sometimed filled
	* in when there is no data to be transferred */
	cmd_entry->control_flags = CF_NO_DATA;
	if (scsi_bufflen(cmd)) {
	if (cmd->sc_data_direction == DMA_TO_DEVICE)
	cmd_entry->control_flags = CF_WRITE;
	else if (cmd->sc_data_direction == DMA_FROM_DEVICE)
	cmd_entry->control_flags = CF_READ;

	ha->bytes_xfered += scsi_bufflen(cmd);
	if (ha->bytes_xfered & ~0xFFFFF){
	ha->total_mbytes_xferred += ha->bytes_xfered >> 20;
	ha->bytes_xfered &= 0xFFFFF;
	}
	}

	/* Set tagged queueing control flags */
	cmd_entry->control_flags \|= CF_SIMPLE_TAG;
	if (scsi_populate_tag_msg(cmd, tag))
	switch (tag[0]) {
	case MSG_HEAD_TAG:
	cmd_entry->control_flags \|= CF_HEAD_TAG;
	break;
	case MSG_ORDERED_TAG:
	cmd_entry->control_flags \|= CF_ORDERED_TAG;
	break;
	}

	qla4xxx_advance_req_ring_ptr(ha);
	qla4xxx_build_scsi_iocbs(srb, cmd_entry, tot_dsds);
	wmb();

	srb->cmd->host_scribble = (unsigned char *)(unsigned long)index;

	/* update counters */
	srb->state = SRB_ACTIVE_STATE;
	srb->flags \|= SRB_DMA_VALID;

	/* Track IOCB used */
	ha->iocb_cnt += req_cnt;
	srb->iocb_cnt = req_cnt;
	ha->req_q_count -= req_cnt;

	ha->isp_ops->queue_iocb(ha);
	spin_unlock_irqrestore(&ha->hardware_lock, flags);

	return QLA_SUCCESS;

	queuing_error:
	if (tot_dsds)
	scsi_dma_unmap(cmd);

	spin_unlock_irqrestore(&ha->hardware_lock, flags);

	return QLA_ERROR;
	}