[SCSI] qla2xxx: T10 DIF support added.

Signed-off-by: Duane Grigsby <duane.grigsby@qlogic.com>
Signed-off-by: Giridhar Malavali <giridhar.malavali@qlogic.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

1 files changed, 677 insertions, 1 deletions

diff --git a/drivers/scsi/qla2xxx/qla_iocb.c b/drivers/scsi/qla2xxx/qla_iocb.c
index d7a9fff15ad..8ef94536541 100644
--- a/drivers/scsi/qla2xxx/qla_iocb.c
+++ b/drivers/scsi/qla2xxx/qla_iocb.c
@@ -145,7 +145,49 @@ qla2x00_prep_cont_type1_iocb(scsi_qla_host_t *vha)
 	return (cont_pkt);
 }
 
-/**
+static inline int
+qla24xx_configure_prot_mode(srb_t *sp, uint16_t *fw_prot_opts)
+{
+	uint8_t	guard = scsi_host_get_guard(sp->cmd->device->host);
+
+	/* We only support T10 DIF right now */
+	if (guard != SHOST_DIX_GUARD_CRC) {
+		DEBUG2(printk(KERN_ERR "Unsupported guard: %d\n", guard));
+		return 0;
+	}
+
+	/* We always use DIFF Bundling for best performance */
+	*fw_prot_opts = 0;
+
+	/* Translate SCSI opcode to a protection opcode */
+	switch (scsi_get_prot_op(sp->cmd)) {
+	case SCSI_PROT_READ_STRIP:
+		*fw_prot_opts |= PO_MODE_DIF_REMOVE;
+		break;
+	case SCSI_PROT_WRITE_INSERT:
+		*fw_prot_opts |= PO_MODE_DIF_INSERT;
+		break;
+	case SCSI_PROT_READ_INSERT:
+		*fw_prot_opts |= PO_MODE_DIF_INSERT;
+		break;
+	case SCSI_PROT_WRITE_STRIP:
+		*fw_prot_opts |= PO_MODE_DIF_REMOVE;
+		break;
+	case SCSI_PROT_READ_PASS:
+		*fw_prot_opts |= PO_MODE_DIF_PASS;
+		break;
+	case SCSI_PROT_WRITE_PASS:
+		*fw_prot_opts |= PO_MODE_DIF_PASS;
+		break;
+	default:	/* Normal Request */
+		*fw_prot_opts |= PO_MODE_DIF_PASS;
+		break;
+	}
+
+	return scsi_prot_sg_count(sp->cmd);
+}
+
+/*
  * qla2x00_build_scsi_iocbs_32() - Build IOCB command utilizing 32bit
  * capable IOCB types.
  *
@@ -636,6 +678,8 @@ qla24xx_calc_iocbs(uint16_t dsds)
 		if ((dsds - 1) % 5)
 			iocbs++;
 	}
+	DEBUG3(printk(KERN_DEBUG "%s(): Required PKT(s) = %d\n",
+	    __func__, iocbs));
 	return iocbs;
 }
 
@@ -716,6 +760,453 @@ qla24xx_build_scsi_iocbs(srb_t *sp, struct cmd_type_7 *cmd_pkt,
 	}
 }
 
+struct fw_dif_context {
+	uint32_t ref_tag;
+	uint16_t app_tag;
+	uint8_t ref_tag_mask[4];	/* Validation/Replacement Mask*/
+	uint8_t app_tag_mask[2];	/* Validation/Replacement Mask*/
+};
+
+/*
+ * qla24xx_set_t10dif_tags_from_cmd - Extract Ref and App tags from SCSI command
+ *
+ */
+static inline void
+qla24xx_set_t10dif_tags(struct scsi_cmnd *cmd, struct fw_dif_context *pkt,
+    unsigned int protcnt)
+{
+	struct sd_dif_tuple *spt;
+	unsigned char op = scsi_get_prot_op(cmd);
+
+	switch (scsi_get_prot_type(cmd)) {
+	/* For TYPE 0 protection: no checking */
+	case SCSI_PROT_DIF_TYPE0:
+		pkt->ref_tag_mask[0] = 0x00;
+		pkt->ref_tag_mask[1] = 0x00;
+		pkt->ref_tag_mask[2] = 0x00;
+		pkt->ref_tag_mask[3] = 0x00;
+		break;
+
+	/*
+	 * For TYPE 2 protection: 16 bit GUARD + 32 bit REF tag has to
+	 * match LBA in CDB + N
+	 */
+	case SCSI_PROT_DIF_TYPE2:
+		break;
+
+	/* For Type 3 protection: 16 bit GUARD only */
+	case SCSI_PROT_DIF_TYPE3:
+		pkt->ref_tag_mask[0] = pkt->ref_tag_mask[1] =
+			pkt->ref_tag_mask[2] = pkt->ref_tag_mask[3] =
+								0x00;
+		break;
+
+	/*
+	 * For TYpe 1 protection: 16 bit GUARD tag, 32 bit REF tag, and
+	 * 16 bit app tag.
+	 */
+	case SCSI_PROT_DIF_TYPE1:
+		if (!ql2xenablehba_err_chk)
+			break;
+
+		if (protcnt && (op == SCSI_PROT_WRITE_STRIP ||
+		    op == SCSI_PROT_WRITE_PASS)) {
+			spt = page_address(sg_page(scsi_prot_sglist(cmd))) +
+			    scsi_prot_sglist(cmd)[0].offset;
+			DEBUG18(printk(KERN_DEBUG
+			    "%s(): LBA from user %p, lba = 0x%x\n",
+			    __func__, spt, (int)spt->ref_tag));
+			pkt->ref_tag = swab32(spt->ref_tag);
+			pkt->app_tag_mask[0] = 0x0;
+			pkt->app_tag_mask[1] = 0x0;
+		} else {
+			pkt->ref_tag = cpu_to_le32((uint32_t)
+			    (0xffffffff & scsi_get_lba(cmd)));
+			pkt->app_tag = __constant_cpu_to_le16(0);
+			pkt->app_tag_mask[0] = 0x0;
+			pkt->app_tag_mask[1] = 0x0;
+		}
+		/* enable ALL bytes of the ref tag */
+		pkt->ref_tag_mask[0] = 0xff;
+		pkt->ref_tag_mask[1] = 0xff;
+		pkt->ref_tag_mask[2] = 0xff;
+		pkt->ref_tag_mask[3] = 0xff;
+		break;
+	}
+
+	DEBUG18(printk(KERN_DEBUG
+	    "%s(): Setting protection Tags: (BIG) ref tag = 0x%x,"
+	    " app tag = 0x%x, prot SG count %d , cmd lba 0x%x,"
+	    " prot_type=%u\n", __func__, pkt->ref_tag, pkt->app_tag, protcnt,
+	    (int)scsi_get_lba(cmd), scsi_get_prot_type(cmd)));
+}
+
+
+static int
+qla24xx_walk_and_build_sglist(struct qla_hw_data *ha, srb_t *sp, uint32_t *dsd,
+	uint16_t tot_dsds)
+{
+	void *next_dsd;
+	uint8_t avail_dsds = 0;
+	uint32_t dsd_list_len;
+	struct dsd_dma *dsd_ptr;
+	struct scatterlist *sg;
+	uint32_t *cur_dsd = dsd;
+	int	i;
+	uint16_t	used_dsds = tot_dsds;
+
+	uint8_t		*cp;
+
+	scsi_for_each_sg(sp->cmd, sg, tot_dsds, i) {
+		dma_addr_t	sle_dma;
+
+		/* Allocate additional continuation packets? */
+		if (avail_dsds == 0) {
+			avail_dsds = (used_dsds > QLA_DSDS_PER_IOCB) ?
+					QLA_DSDS_PER_IOCB : used_dsds;
+			dsd_list_len = (avail_dsds + 1) * 12;
+			used_dsds -= avail_dsds;
+
+			/* allocate tracking DS */
+			dsd_ptr = kzalloc(sizeof(struct dsd_dma), GFP_ATOMIC);
+			if (!dsd_ptr)
+				return 1;
+
+			/* allocate new list */
+			dsd_ptr->dsd_addr = next_dsd =
+			    dma_pool_alloc(ha->dl_dma_pool, GFP_ATOMIC,
+				&dsd_ptr->dsd_list_dma);
+
+			if (!next_dsd) {
+				/*
+				 * Need to cleanup only this dsd_ptr, rest
+				 * will be done by sp_free_dma()
+				 */
+				kfree(dsd_ptr);
+				return 1;
+			}
+
+			list_add_tail(&dsd_ptr->list,
+			    &((struct crc_context *)sp->ctx)->dsd_list);
+
+			sp->flags |= SRB_CRC_CTX_DSD_VALID;
+
+			/* add new list to cmd iocb or last list */
+			*cur_dsd++ = cpu_to_le32(LSD(dsd_ptr->dsd_list_dma));
+			*cur_dsd++ = cpu_to_le32(MSD(dsd_ptr->dsd_list_dma));
+			*cur_dsd++ = dsd_list_len;
+			cur_dsd = (uint32_t *)next_dsd;
+		}
+		sle_dma = sg_dma_address(sg);
+		DEBUG18(printk("%s(): %p, sg entry %d - addr =0x%x 0x%x,"
+		    " len =%d\n", __func__ , cur_dsd, i, LSD(sle_dma),
+		    MSD(sle_dma), sg_dma_len(sg)));
+		*cur_dsd++ = cpu_to_le32(LSD(sle_dma));
+		*cur_dsd++ = cpu_to_le32(MSD(sle_dma));
+		*cur_dsd++ = cpu_to_le32(sg_dma_len(sg));
+		avail_dsds--;
+
+		if (scsi_get_prot_op(sp->cmd) == SCSI_PROT_WRITE_PASS) {
+			cp = page_address(sg_page(sg)) + sg->offset;
+			DEBUG18(printk("%s(): User Data buffer= %p:\n",
+			    __func__ , cp));
+		}
+	}
+	/* Null termination */
+	*cur_dsd++ = 0;
+	*cur_dsd++ = 0;
+	*cur_dsd++ = 0;
+	return 0;
+}
+
+static int
+qla24xx_walk_and_build_prot_sglist(struct qla_hw_data *ha, srb_t *sp,
+							uint32_t *dsd,
+	uint16_t tot_dsds)
+{
+	void *next_dsd;
+	uint8_t avail_dsds = 0;
+	uint32_t dsd_list_len;
+	struct dsd_dma *dsd_ptr;
+	struct scatterlist *sg;
+	int	i;
+	struct scsi_cmnd *cmd;
+	uint32_t *cur_dsd = dsd;
+	uint16_t	used_dsds = tot_dsds;
+
+	uint8_t		*cp;
+
+
+	cmd = sp->cmd;
+	scsi_for_each_prot_sg(cmd, sg, tot_dsds, i) {
+		dma_addr_t	sle_dma;
+
+		/* Allocate additional continuation packets? */
+		if (avail_dsds == 0) {
+			avail_dsds = (used_dsds > QLA_DSDS_PER_IOCB) ?
+						QLA_DSDS_PER_IOCB : used_dsds;
+			dsd_list_len = (avail_dsds + 1) * 12;
+			used_dsds -= avail_dsds;
+
+			/* allocate tracking DS */
+			dsd_ptr = kzalloc(sizeof(struct dsd_dma), GFP_ATOMIC);
+			if (!dsd_ptr)
+				return 1;
+
+			/* allocate new list */
+			dsd_ptr->dsd_addr = next_dsd =
+			    dma_pool_alloc(ha->dl_dma_pool, GFP_ATOMIC,
+				&dsd_ptr->dsd_list_dma);
+
+			if (!next_dsd) {
+				/*
+				 * Need to cleanup only this dsd_ptr, rest
+				 * will be done by sp_free_dma()
+				 */
+				kfree(dsd_ptr);
+				return 1;
+			}
+
+			list_add_tail(&dsd_ptr->list,
+			    &((struct crc_context *)sp->ctx)->dsd_list);
+
+			sp->flags |= SRB_CRC_CTX_DSD_VALID;
+
+			/* add new list to cmd iocb or last list */
+			*cur_dsd++ = cpu_to_le32(LSD(dsd_ptr->dsd_list_dma));
+			*cur_dsd++ = cpu_to_le32(MSD(dsd_ptr->dsd_list_dma));
+			*cur_dsd++ = dsd_list_len;
+			cur_dsd = (uint32_t *)next_dsd;
+		}
+		sle_dma = sg_dma_address(sg);
+		if (scsi_get_prot_op(sp->cmd) == SCSI_PROT_WRITE_PASS) {
+			DEBUG18(printk(KERN_DEBUG
+			    "%s(): %p, sg entry %d - addr =0x%x"
+			    "0x%x, len =%d\n", __func__ , cur_dsd, i,
+			    LSD(sle_dma), MSD(sle_dma), sg_dma_len(sg)));
+		}
+		*cur_dsd++ = cpu_to_le32(LSD(sle_dma));
+		*cur_dsd++ = cpu_to_le32(MSD(sle_dma));
+		*cur_dsd++ = cpu_to_le32(sg_dma_len(sg));
+
+		if (scsi_get_prot_op(sp->cmd) == SCSI_PROT_WRITE_PASS) {
+			cp = page_address(sg_page(sg)) + sg->offset;
+			DEBUG18(printk("%s(): Protection Data buffer = %p:\n",
+			    __func__ , cp));
+		}
+		avail_dsds--;
+	}
+	/* Null termination */
+	*cur_dsd++ = 0;
+	*cur_dsd++ = 0;
+	*cur_dsd++ = 0;
+	return 0;
+}
+
+/**
+ * qla24xx_build_scsi_crc_2_iocbs() - Build IOCB command utilizing Command
+ *							Type 6 IOCB types.
+ *
+ * @sp: SRB command to process
+ * @cmd_pkt: Command type 3 IOCB
+ * @tot_dsds: Total number of segments to transfer
+ */
+static inline int
+qla24xx_build_scsi_crc_2_iocbs(srb_t *sp, struct cmd_type_crc_2 *cmd_pkt,
+    uint16_t tot_dsds, uint16_t tot_prot_dsds, uint16_t fw_prot_opts)
+{
+	uint32_t		*cur_dsd, *fcp_dl;
+	scsi_qla_host_t		*vha;
+	struct scsi_cmnd	*cmd;
+	struct scatterlist	*cur_seg;
+	int			sgc;
+	uint32_t		total_bytes;
+	uint32_t		data_bytes;
+	uint32_t		dif_bytes;
+	uint8_t			bundling = 1;
+	uint16_t		blk_size;
+	uint8_t			*clr_ptr;
+	struct crc_context	*crc_ctx_pkt = NULL;
+	struct qla_hw_data	*ha;
+	uint8_t			additional_fcpcdb_len;
+	uint16_t		fcp_cmnd_len;
+	struct fcp_cmnd		*fcp_cmnd;
+	dma_addr_t		crc_ctx_dma;
+
+	cmd = sp->cmd;
+
+	sgc = 0;
+	/* Update entry type to indicate Command Type CRC_2 IOCB */
+	*((uint32_t *)(&cmd_pkt->entry_type)) =
+	    __constant_cpu_to_le32(COMMAND_TYPE_CRC_2);
+
+	/* No data transfer */
+	data_bytes = scsi_bufflen(cmd);
+	if (!data_bytes || cmd->sc_data_direction == DMA_NONE) {
+		DEBUG18(printk(KERN_INFO "%s: Zero data bytes or DMA-NONE %d\n",
+		    __func__, data_bytes));
+		cmd_pkt->byte_count = __constant_cpu_to_le32(0);
+		return QLA_SUCCESS;
+	}
+
+	vha = sp->fcport->vha;
+	ha = vha->hw;
+
+	DEBUG18(printk(KERN_DEBUG
+	    "%s(%ld): Executing cmd sp %p, pid=%ld, prot_op=%u.\n", __func__,
+	    vha->host_no, sp, cmd->serial_number, scsi_get_prot_op(sp->cmd)));
+
+	cmd_pkt->vp_index = sp->fcport->vp_idx;
+
+	/* Set transfer direction */
+	if (cmd->sc_data_direction == DMA_TO_DEVICE) {
+		cmd_pkt->control_flags =
+		    __constant_cpu_to_le16(CF_WRITE_DATA);
+	} else if (cmd->sc_data_direction == DMA_FROM_DEVICE) {
+		cmd_pkt->control_flags =
+		    __constant_cpu_to_le16(CF_READ_DATA);
+	}
+
+	tot_prot_dsds = scsi_prot_sg_count(cmd);
+	if (!tot_prot_dsds)
+		bundling = 0;
+
+	/* Allocate CRC context from global pool */
+	crc_ctx_pkt = sp->ctx = dma_pool_alloc(ha->dl_dma_pool,
+	    GFP_ATOMIC, &crc_ctx_dma);
+
+	if (!crc_ctx_pkt)
+		goto crc_queuing_error;
+
+	/* Zero out CTX area. */
+	clr_ptr = (uint8_t *)crc_ctx_pkt;
+	memset(clr_ptr, 0, sizeof(*crc_ctx_pkt));
+
+	crc_ctx_pkt->crc_ctx_dma = crc_ctx_dma;
+
+	sp->flags |= SRB_CRC_CTX_DMA_VALID;
+
+	/* Set handle */
+	crc_ctx_pkt->handle = cmd_pkt->handle;
+
+	INIT_LIST_HEAD(&crc_ctx_pkt->dsd_list);
+
+	qla24xx_set_t10dif_tags(cmd, (struct fw_dif_context *)
+	    &crc_ctx_pkt->ref_tag, tot_prot_dsds);
+
+	cmd_pkt->crc_context_address[0] = cpu_to_le32(LSD(crc_ctx_dma));
+	cmd_pkt->crc_context_address[1] = cpu_to_le32(MSD(crc_ctx_dma));
+	cmd_pkt->crc_context_len = CRC_CONTEXT_LEN_FW;
+
+	/* Determine SCSI command length -- align to 4 byte boundary */
+	if (cmd->cmd_len > 16) {
+		DEBUG18(printk(KERN_INFO "%s(): **** SCSI CMD > 16\n",
+		    __func__));
+		additional_fcpcdb_len = cmd->cmd_len - 16;
+		if ((cmd->cmd_len % 4) != 0) {
+			/* SCSI cmd > 16 bytes must be multiple of 4 */
+			goto crc_queuing_error;
+		}
+		fcp_cmnd_len = 12 + cmd->cmd_len + 4;
+	} else {
+		additional_fcpcdb_len = 0;
+		fcp_cmnd_len = 12 + 16 + 4;
+	}
+
+	fcp_cmnd = &crc_ctx_pkt->fcp_cmnd;
+
+	fcp_cmnd->additional_cdb_len = additional_fcpcdb_len;
+	if (cmd->sc_data_direction == DMA_TO_DEVICE)
+		fcp_cmnd->additional_cdb_len |= 1;
+	else if (cmd->sc_data_direction == DMA_FROM_DEVICE)
+		fcp_cmnd->additional_cdb_len |= 2;
+
+	int_to_scsilun(sp->cmd->device->lun, &fcp_cmnd->lun);
+	memcpy(fcp_cmnd->cdb, cmd->cmnd, cmd->cmd_len);
+	cmd_pkt->fcp_cmnd_dseg_len = cpu_to_le16(fcp_cmnd_len);
+	cmd_pkt->fcp_cmnd_dseg_address[0] = cpu_to_le32(
+	    LSD(crc_ctx_dma + CRC_CONTEXT_FCPCMND_OFF));
+	cmd_pkt->fcp_cmnd_dseg_address[1] = cpu_to_le32(
+	    MSD(crc_ctx_dma + CRC_CONTEXT_FCPCMND_OFF));
+	fcp_cmnd->task_attribute = 0;
+	fcp_cmnd->task_managment = 0;
+
+	cmd_pkt->fcp_rsp_dseg_len = 0; /* Let response come in status iocb */
+
+	DEBUG18(printk(KERN_INFO "%s(%ld): Total SG(s) Entries %d, Data"
+	    "entries %d, data bytes %d, Protection entries %d\n",
+	    __func__, vha->host_no, tot_dsds, (tot_dsds-tot_prot_dsds),
+	    data_bytes, tot_prot_dsds));
+
+	/* Compute dif len and adjust data len to incude protection */
+	total_bytes = data_bytes;
+	dif_bytes = 0;
+	blk_size = cmd->device->sector_size;
+	if (scsi_get_prot_type(cmd) == SCSI_PROT_DIF_TYPE1) {
+		dif_bytes = (data_bytes / blk_size) * 8;
+		total_bytes += dif_bytes;
+	}
+
+	if (!ql2xenablehba_err_chk)
+		fw_prot_opts |= 0x10; /* Disable Guard tag checking */
+
+	if (!bundling) {
+		cur_dsd = (uint32_t *) &crc_ctx_pkt->u.nobundling.data_address;
+	} else {
+		/*
+		 * Configure Bundling if we need to fetch interlaving
+		 * protection PCI accesses
+		 */
+		fw_prot_opts |= PO_ENABLE_DIF_BUNDLING;
+		crc_ctx_pkt->u.bundling.dif_byte_count = cpu_to_le32(dif_bytes);
+		crc_ctx_pkt->u.bundling.dseg_count = cpu_to_le16(tot_dsds -
+							tot_prot_dsds);
+		cur_dsd = (uint32_t *) &crc_ctx_pkt->u.bundling.data_address;
+	}
+
+	/* Finish the common fields of CRC pkt */
+	crc_ctx_pkt->blk_size = cpu_to_le16(blk_size);
+	crc_ctx_pkt->prot_opts = cpu_to_le16(fw_prot_opts);
+	crc_ctx_pkt->byte_count = cpu_to_le32(data_bytes);
+	crc_ctx_pkt->guard_seed = __constant_cpu_to_le16(0);
+	/* Fibre channel byte count */
+	cmd_pkt->byte_count = cpu_to_le32(total_bytes);
+	fcp_dl = (uint32_t *)(crc_ctx_pkt->fcp_cmnd.cdb + 16 +
+	    additional_fcpcdb_len);
+	*fcp_dl = htonl(total_bytes);
+
+	DEBUG18(printk(KERN_INFO "%s(%ld): dif bytes = 0x%x (%d), total bytes"
+	    " = 0x%x (%d), dat block size =0x%x (%d)\n", __func__,
+	    vha->host_no, dif_bytes, dif_bytes, total_bytes, total_bytes,
+	    crc_ctx_pkt->blk_size, crc_ctx_pkt->blk_size));
+
+	/* Walks data segments */
+
+	cmd_pkt->control_flags |=
+	    __constant_cpu_to_le16(CF_DATA_SEG_DESCR_ENABLE);
+	if (qla24xx_walk_and_build_sglist(ha, sp, cur_dsd,
+	    (tot_dsds - tot_prot_dsds)))
+		goto crc_queuing_error;
+
+	if (bundling && tot_prot_dsds) {
+		/* Walks dif segments */
+		cur_seg = scsi_prot_sglist(cmd);
+		cmd_pkt->control_flags |=
+			__constant_cpu_to_le16(CF_DIF_SEG_DESCR_ENABLE);
+		cur_dsd = (uint32_t *) &crc_ctx_pkt->u.bundling.dif_address;
+		if (qla24xx_walk_and_build_prot_sglist(ha, sp, cur_dsd,
+		    tot_prot_dsds))
+			goto crc_queuing_error;
+	}
+	return QLA_SUCCESS;
+
+crc_queuing_error:
+	DEBUG18(qla_printk(KERN_INFO, ha,
+	    "CMD sent FAILED crc_q error:sp = %p\n", sp));
+	/* Cleanup will be performed by the caller */
+
+	return QLA_FUNCTION_FAILED;
+}
 
 /**
  * qla24xx_start_scsi() - Send a SCSI command to the ISP
@@ -869,6 +1360,191 @@ queuing_error:
 	return QLA_FUNCTION_FAILED;
 }
 
+
+/**
+ * qla24xx_dif_start_scsi() - Send a SCSI command to the ISP
+ * @sp: command to send to the ISP
+ *
+ * Returns non-zero if a failure occurred, else zero.
+ */
+int
+qla24xx_dif_start_scsi(srb_t *sp)
+{
+	int			nseg;
+	unsigned long		flags;
+	uint32_t		*clr_ptr;
+	uint32_t		index;
+	uint32_t		handle;
+	uint16_t		cnt;
+	uint16_t		req_cnt = 0;
+	uint16_t		tot_dsds;
+	uint16_t		tot_prot_dsds;
+	uint16_t		fw_prot_opts = 0;
+	struct req_que		*req = NULL;
+	struct rsp_que		*rsp = NULL;
+	struct scsi_cmnd	*cmd = sp->cmd;
+	struct scsi_qla_host	*vha = sp->fcport->vha;
+	struct qla_hw_data	*ha = vha->hw;
+	struct cmd_type_crc_2	*cmd_pkt;
+	uint32_t		status = 0;
+
+#define QDSS_GOT_Q_SPACE	BIT_0
+
+	/* Only process protection in this routine */
+	if (scsi_get_prot_op(cmd) == SCSI_PROT_NORMAL)
+		return qla24xx_start_scsi(sp);
+
+	/* Setup device pointers. */
+
+	qla25xx_set_que(sp, &rsp);
+	req = vha->req;
+
+	/* So we know we haven't pci_map'ed anything yet */
+	tot_dsds = 0;
+
+	/* Send marker if required */
+	if (vha->marker_needed != 0) {
+		if (qla2x00_marker(vha, req, rsp, 0, 0, MK_SYNC_ALL) !=
+		    QLA_SUCCESS)
+			return QLA_FUNCTION_FAILED;
+		vha->marker_needed = 0;
+	}
+
+	/* Acquire ring specific lock */
+	spin_lock_irqsave(&ha->hardware_lock, flags);
+
+	/* Check for room in outstanding command list. */
+	handle = req->current_outstanding_cmd;
+	for (index = 1; index < MAX_OUTSTANDING_COMMANDS; index++) {
+		handle++;
+		if (handle == MAX_OUTSTANDING_COMMANDS)
+			handle = 1;
+		if (!req->outstanding_cmds[handle])
+			break;
+	}
+
+	if (index == MAX_OUTSTANDING_COMMANDS)
+		goto queuing_error;
+
+	/* Compute number of required data segments */
+	/* Map the sg table so we have an accurate count of sg entries needed */
+	if (scsi_sg_count(cmd)) {
+		nseg = dma_map_sg(&ha->pdev->dev, scsi_sglist(cmd),
+		    scsi_sg_count(cmd), cmd->sc_data_direction);
+		if (unlikely(!nseg))
+			goto queuing_error;
+		else
+			sp->flags |= SRB_DMA_VALID;
+	} else
+		nseg = 0;
+
+	/* number of required data segments */
+	tot_dsds = nseg;
+
+	/* Compute number of required protection segments */
+	if (qla24xx_configure_prot_mode(sp, &fw_prot_opts)) {
+		nseg = dma_map_sg(&ha->pdev->dev, scsi_prot_sglist(cmd),
+		    scsi_prot_sg_count(cmd), cmd->sc_data_direction);
+		if (unlikely(!nseg))
+			goto queuing_error;
+		else
+			sp->flags |= SRB_CRC_PROT_DMA_VALID;
+	} else {
+		nseg = 0;
+	}
+
+	req_cnt = 1;
+	/* Total Data and protection sg segment(s) */
+	tot_prot_dsds = nseg;
+	tot_dsds += nseg;
+	if (req->cnt < (req_cnt + 2)) {
+		cnt = RD_REG_DWORD_RELAXED(req->req_q_out);
+
+		if (req->ring_index < cnt)
+			req->cnt = cnt - req->ring_index;
+		else
+			req->cnt = req->length -
+				(req->ring_index - cnt);
+	}
+
+	if (req->cnt < (req_cnt + 2))
+		goto queuing_error;
+
+	status |= QDSS_GOT_Q_SPACE;
+
+	/* Build header part of command packet (excluding the OPCODE). */
+	req->current_outstanding_cmd = handle;
+	req->outstanding_cmds[handle] = sp;
+	sp->cmd->host_scribble = (unsigned char *)(unsigned long)handle;
+	req->cnt -= req_cnt;
+
+	/* Fill-in common area */
+	cmd_pkt = (struct cmd_type_crc_2 *)req->ring_ptr;
+	cmd_pkt->handle = MAKE_HANDLE(req->id, handle);
+
+	clr_ptr = (uint32_t *)cmd_pkt + 2;
+	memset(clr_ptr, 0, REQUEST_ENTRY_SIZE - 8);
+
+	/* Set NPORT-ID and LUN number*/
+	cmd_pkt->nport_handle = cpu_to_le16(sp->fcport->loop_id);
+	cmd_pkt->port_id[0] = sp->fcport->d_id.b.al_pa;
+	cmd_pkt->port_id[1] = sp->fcport->d_id.b.area;
+	cmd_pkt->port_id[2] = sp->fcport->d_id.b.domain;
+
+	int_to_scsilun(sp->cmd->device->lun, &cmd_pkt->lun);
+	host_to_fcp_swap((uint8_t *)&cmd_pkt->lun, sizeof(cmd_pkt->lun));
+
+	/* Total Data and protection segment(s) */
+	cmd_pkt->dseg_count = cpu_to_le16(tot_dsds);
+
+	/* Build IOCB segments and adjust for data protection segments */
+	if (qla24xx_build_scsi_crc_2_iocbs(sp, (struct cmd_type_crc_2 *)
+	    req->ring_ptr, tot_dsds, tot_prot_dsds, fw_prot_opts) !=
+		QLA_SUCCESS)
+		goto queuing_error;
+
+	cmd_pkt->entry_count = (uint8_t)req_cnt;
+	/* Specify response queue number where completion should happen */
+	cmd_pkt->entry_status = (uint8_t) rsp->id;
+	cmd_pkt->timeout = __constant_cpu_to_le16(0);
+	wmb();
+
+	/* Adjust ring index. */
+	req->ring_index++;
+	if (req->ring_index == req->length) {
+		req->ring_index = 0;
+		req->ring_ptr = req->ring;
+	} else
+		req->ring_ptr++;
+
+	/* Set chip new ring index. */
+	WRT_REG_DWORD(req->req_q_in, req->ring_index);
+	RD_REG_DWORD_RELAXED(&ha->iobase->isp24.hccr);
+
+	/* Manage unprocessed RIO/ZIO commands in response queue. */
+	if (vha->flags.process_response_queue &&
+	    rsp->ring_ptr->signature != RESPONSE_PROCESSED)
+		qla24xx_process_response_queue(vha, rsp);
+
+	spin_unlock_irqrestore(&ha->hardware_lock, flags);
+
+	return QLA_SUCCESS;
+
+queuing_error:
+	if (status & QDSS_GOT_Q_SPACE) {
+		req->outstanding_cmds[handle] = NULL;
+		req->cnt += req_cnt;
+	}
+	/* Cleanup will be performed by the caller (queuecommand) */
+
+	spin_unlock_irqrestore(&ha->hardware_lock, flags);
+
+	DEBUG18(qla_printk(KERN_INFO, ha,
+	    "CMD sent FAILED SCSI prot_op:%02x\n", scsi_get_prot_op(cmd)));
+	return QLA_FUNCTION_FAILED;
+}
+
+
 static void qla25xx_set_que(srb_t *sp, struct rsp_que **rsp)
 {
 	struct scsi_cmnd *cmd = sp->cmd;