[SCSI] Initial Commit of qla4xxx

open-iSCSI driver for Qlogic Corporation's iSCSI HBAs

Signed-off-by: Ravi Anand <ravi.anand@qlogic.com>
Signed-off-by: David Somayajulu <david.somayajulu@qlogic.com>
Signed-off-by: Doug Maxey <dwm@bubba.enoyolf.org>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

1 files changed, 368 insertions, 0 deletions

diff --git a/drivers/scsi/qla4xxx/ql4_iocb.c b/drivers/scsi/qla4xxx/ql4_iocb.c
new file mode 100644
index 000000000000..c0a254b89a30
--- /dev/null
+++ b/drivers/scsi/qla4xxx/ql4_iocb.c
@@ -0,0 +1,368 @@
+/*
+ * QLogic iSCSI HBA Driver
+ * Copyright (c)  2003-2006 QLogic Corporation
+ *
+ * See LICENSE.qla4xxx for copyright and licensing details.
+ */
+
+#include "ql4_def.h"
+
+#include <scsi/scsi_tcq.h>
+
+/**
+ * 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
+ **/
+int qla4xxx_get_req_pkt(struct scsi_qla_host *ha,
+			struct queue_entry **queue_entry)
+{
+	uint16_t request_in;
+	uint8_t status = QLA_SUCCESS;
+
+	*queue_entry = ha->request_ptr;
+
+	/* get the latest request_in and request_out index */
+	request_in = ha->request_in;
+	ha->request_out = (uint16_t) le32_to_cpu(ha->shadow_regs->req_q_out);
+
+	/* Advance request queue pointer and check for queue full */
+	if (request_in == (REQUEST_QUEUE_DEPTH - 1)) {
+		request_in = 0;
+		ha->request_ptr = ha->request_ring;
+	} else {
+		request_in++;
+		ha->request_ptr++;
+	}
+
+	/* request queue is full, try again later */
+	if ((ha->iocb_cnt + 1) >= ha->iocb_hiwat) {
+		/* restore request pointer */
+		ha->request_ptr = *queue_entry;
+		status = QLA_ERROR;
+	} else {
+		ha->request_in = request_in;
+		memset(*queue_entry, 0, sizeof(**queue_entry));
+	}
+
+	return status;
+}
+
+/**
+ * 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)
+{
+	struct 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(MM_LUN_RESET);
+	int_to_scsilun(lun, &marker_entry->lun);
+	wmb();
+
+	/* Tell ISP it's got a new I/O request */
+	writel(ha->request_in, &ha->reg->req_q_in);
+	readl(&ha->reg->req_q_in);
+
+exit_send_marker:
+	spin_unlock_irqrestore(&ha->hardware_lock, flags);
+	return status;
+}
+
+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;
+
+	/* 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++;
+	}
+
+	/* 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;
+}
+
+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;
+}
+
+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;
+
+	cmd = srb->cmd;
+	ha = srb->ha;
+
+	if (cmd->request_bufflen == 0 || 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]);
+
+	/* Load data segments */
+	if (cmd->use_sg) {
+		struct scatterlist *cur_seg;
+		struct scatterlist *end_seg;
+
+		cur_seg = (struct scatterlist *)cmd->request_buffer;
+		end_seg = cur_seg + tot_dsds;
+		while (cur_seg < end_seg) {
+			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(cur_seg);
+			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(cur_seg));
+			avail_dsds--;
+
+			cur_dsd++;
+			cur_seg++;
+		}
+	} else {
+		cur_dsd->base.addrLow = cpu_to_le32(LSDW(srb->dma_handle));
+		cur_dsd->base.addrHigh = cpu_to_le32(MSDW(srb->dma_handle));
+		cur_dsd->count = cpu_to_le32(cmd->request_bufflen);
+	}
+}
+
+/**
+ * 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;
+	struct scatterlist *sg = NULL;
+
+	uint16_t tot_dsds;
+	uint16_t req_cnt;
+
+	unsigned long flags;
+	uint16_t cnt;
+	uint32_t index;
+	char tag[2];
+
+	/* Get real lun and adapter */
+	ddb_entry = srb->ddb;
+
+	/* Send marker(s) if needed. */
+	if (ha->marker_needed == 1) {
+		if (qla4xxx_send_marker_iocb(ha, ddb_entry,
+					     cmd->device->lun) != QLA_SUCCESS)
+			return QLA_ERROR;
+
+		ha->marker_needed = 0;
+	}
+	tot_dsds = 0;
+
+	/* Acquire hardware specific lock */
+	spin_lock_irqsave(&ha->hardware_lock, flags);
+
+	index = (uint32_t)cmd->request->tag;
+
+	/* Calculate the number of request entries needed. */
+	if (cmd->use_sg) {
+		sg = (struct scatterlist *)cmd->request_buffer;
+		tot_dsds = pci_map_sg(ha->pdev, sg, cmd->use_sg,
+				      cmd->sc_data_direction);
+		if (tot_dsds == 0)
+			goto queuing_error;
+	} else if (cmd->request_bufflen) {
+		dma_addr_t	req_dma;
+
+		req_dma = pci_map_single(ha->pdev, cmd->request_buffer,
+					 cmd->request_bufflen,
+					 cmd->sc_data_direction);
+		if (dma_mapping_error(req_dma))
+			goto queuing_error;
+
+		srb->dma_handle = req_dma;
+		tot_dsds = 1;
+	}
+	req_cnt = qla4xxx_calc_request_entries(tot_dsds);
+
+	if (ha->req_q_count < (req_cnt + 2)) {
+		cnt = (uint16_t) le32_to_cpu(ha->shadow_regs->req_q_out);
+		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);
+	}
+
+	if (ha->req_q_count < (req_cnt + 2))
+		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(cmd->request_bufflen);
+	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 (cmd->request_bufflen) {
+		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;
+	}
+
+	/* 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;
+		}
+
+
+	/* Advance request queue pointer */
+	ha->request_in++;
+	if (ha->request_in == REQUEST_QUEUE_DEPTH) {
+		ha->request_in = 0;
+		ha->request_ptr = ha->request_ring;
+	} else
+		ha->request_ptr++;
+
+
+	qla4xxx_build_scsi_iocbs(srb, cmd_entry, tot_dsds);
+	wmb();
+
+	/*
+	 * 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;
+	}
+
+	srb->cmd->host_scribble = (unsigned char *)srb;
+
+	/* 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;
+
+	/* Debug print statements */
+	writel(ha->request_in, &ha->reg->req_q_in);
+	readl(&ha->reg->req_q_in);
+	spin_unlock_irqrestore(&ha->hardware_lock, flags);
+
+	return QLA_SUCCESS;
+
+queuing_error:
+
+	if (cmd->use_sg && tot_dsds) {
+		sg = (struct scatterlist *) cmd->request_buffer;
+		pci_unmap_sg(ha->pdev, sg, cmd->use_sg,
+			     cmd->sc_data_direction);
+	} else if (tot_dsds)
+		pci_unmap_single(ha->pdev, srb->dma_handle,
+				 cmd->request_bufflen, cmd->sc_data_direction);
+	spin_unlock_irqrestore(&ha->hardware_lock, flags);
+
+	return QLA_ERROR;
+}
+