[SCSI] qla4xxx: support iscsiadm session mgmt

Add scsi_transport_iscsi hooks in qla4xxx to support
iSCSI session management using iscsiadm.

This patch is based on discussion here
http://groups.google.com/group/open-iscsi/browse_thread/thread/e89fd888baf656a0#

Now users can use iscsiadm to do target discovery and do login/logout to
individual targets using the qla4xxx iSCSI class interface.

This patch leaves some dead code, but to make it easier to review
we are leaving and in the next patch we will remove that old code.

V2 - NOTE: Added code to avoid waiting for AEN during login/logout
in the driver, instead added a kernel to user event
to notify iscsid about login status. Because of this
iscsid will not get blocked.

Signed-off-by: Manish Rangankar <manish.rangankar@qlogic.com>
Signed-off-by: Lalit Chandivade <lalit.chandivade@qlogic.com>
Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

1 files changed, 67 insertions, 14 deletions

diff --git a/drivers/scsi/qla4xxx/ql4_isr.c b/drivers/scsi/qla4xxx/ql4_isr.c
index 0e72921c752d..ee1104a3686c 100644
--- a/drivers/scsi/qla4xxx/ql4_isr.c
+++ b/drivers/scsi/qla4xxx/ql4_isr.c
@@ -224,8 +224,8 @@ static void qla4xxx_status_entry(struct scsi_qla_host *ha,
 		 * I/O to this device.	We should get a ddb state change
 		 * AEN soon.
 		 */
-		if (atomic_read(&ddb_entry->state) == DDB_STATE_ONLINE)
-			qla4xxx_mark_device_missing(ha, ddb_entry);
+		if (iscsi_is_session_online(ddb_entry->sess))
+			qla4xxx_mark_device_missing(ddb_entry->sess);
 		break;
 
 	case SCS_DATA_UNDERRUN:
@@ -306,8 +306,8 @@ static void qla4xxx_status_entry(struct scsi_qla_host *ha,
 		 * send I/O to this device.  We should get a ddb
 		 * state change AEN soon.
 		 */
-		if (atomic_read(&ddb_entry->state) == DDB_STATE_ONLINE)
-			qla4xxx_mark_device_missing(ha, ddb_entry);
+		if (iscsi_is_session_online(ddb_entry->sess))
+			qla4xxx_mark_device_missing(ddb_entry->sess);
 
 		cmd->result = DID_TRANSPORT_DISRUPTED << 16;
 		break;
@@ -341,6 +341,51 @@ status_entry_exit:
 }
 
 /**
+ * qla4xxx_passthru_status_entry - processes passthru status IOCBs (0x3C)
+ * @ha: Pointer to host adapter structure.
+ * @sts_entry: Pointer to status entry structure.
+ **/
+static void qla4xxx_passthru_status_entry(struct scsi_qla_host *ha,
+					  struct passthru_status *sts_entry)
+{
+	struct iscsi_task *task;
+	struct ddb_entry *ddb_entry;
+	struct ql4_task_data *task_data;
+	struct iscsi_cls_conn *cls_conn;
+	struct iscsi_conn *conn;
+	itt_t itt;
+	uint32_t fw_ddb_index;
+
+	itt = sts_entry->handle;
+	fw_ddb_index = le32_to_cpu(sts_entry->target);
+
+	ddb_entry = qla4xxx_lookup_ddb_by_fw_index(ha, fw_ddb_index);
+
+	if (ddb_entry == NULL) {
+		ql4_printk(KERN_ERR, ha, "%s: Invalid target index = 0x%x\n",
+			   __func__, sts_entry->target);
+		return;
+	}
+
+	cls_conn = ddb_entry->conn;
+	conn = cls_conn->dd_data;
+	spin_lock(&conn->session->lock);
+	task = iscsi_itt_to_task(conn, itt);
+	spin_unlock(&conn->session->lock);
+
+	if (task == NULL) {
+		ql4_printk(KERN_ERR, ha, "%s: Task is NULL\n", __func__);
+		return;
+	}
+
+	task_data = task->dd_data;
+	memcpy(&task_data->sts, sts_entry, sizeof(struct passthru_status));
+	ha->req_q_count += task_data->iocb_req_cnt;
+	ha->iocb_cnt -= task_data->iocb_req_cnt;
+	queue_work(ha->task_wq, &task_data->task_work);
+}
+
+/**
  * qla4xxx_process_response_queue - process response queue completions
  * @ha: Pointer to host adapter structure.
  *
@@ -375,6 +420,14 @@ void qla4xxx_process_response_queue(struct scsi_qla_host *ha)
 			break;
 
 		case ET_PASSTHRU_STATUS:
+			if (sts_entry->hdr.systemDefined == SD_ISCSI_PDU)
+				qla4xxx_passthru_status_entry(ha,
+					(struct passthru_status *)sts_entry);
+			else
+				ql4_printk(KERN_ERR, ha,
+					   "%s: Invalid status received\n",
+					   __func__);
+
 			break;
 
 		case ET_STATUS_CONTINUATION:
@@ -1009,23 +1062,23 @@ void qla4xxx_process_aen(struct scsi_qla_host * ha, uint8_t process_aen)
 
 		switch (mbox_sts[0]) {
 		case MBOX_ASTS_DATABASE_CHANGED:
-			if (process_aen == FLUSH_DDB_CHANGED_AENS) {
+			switch (process_aen) {
+			case FLUSH_DDB_CHANGED_AENS:
 				DEBUG2(printk("scsi%ld: AEN[%d] %04x, index "
 					      "[%d] state=%04x FLUSHED!\n",
 					      ha->host_no, ha->aen_out,
 					      mbox_sts[0], mbox_sts[2],
 					      mbox_sts[3]));
 				break;
+			case PROCESS_ALL_AENS:
+			default:
+				/* Specific device. */
+				if (mbox_sts[1] == 1)
+					qla4xxx_process_ddb_changed(ha,
+						mbox_sts[2], mbox_sts[3],
+						mbox_sts[4]);
+				break;
 			}
-		case PROCESS_ALL_AENS:
-		default:
-			if (mbox_sts[1] == 0) {	/* Global DB change. */
-				qla4xxx_reinitialize_ddb_list(ha);
-			} else if (mbox_sts[1] == 1) {	/* Specific device. */
-				qla4xxx_process_ddb_changed(ha, mbox_sts[2],
-						mbox_sts[3], mbox_sts[4]);
-			}
-			break;
 		}
 		spin_lock_irqsave(&ha->hardware_lock, flags);
 	}