1 files changed, 148 insertions, 88 deletions

diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
index 809d32d..dfaa8ad 100644
--- a/drivers/scsi/libiscsi.c
+++ b/drivers/scsi/libiscsi.c
@@ -38,6 +38,28 @@
 #include <scsi/scsi_transport_iscsi.h>
 #include <scsi/libiscsi.h>
 
+static int iscsi_dbg_lib;
+module_param_named(debug_libiscsi, iscsi_dbg_lib, int, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(debug_libiscsi, "Turn on debugging for libiscsi module. "
+		 "Set to 1 to turn on, and zero to turn off. Default "
+		 "is off.");
+
+#define ISCSI_DBG_CONN(_conn, dbg_fmt, arg...)			\
+	do {							\
+		if (iscsi_dbg_lib)				\
+			iscsi_conn_printk(KERN_INFO, _conn,	\
+					     "%s " dbg_fmt,	\
+					     __func__, ##arg);	\
+	} while (0);
+
+#define ISCSI_DBG_SESSION(_session, dbg_fmt, arg...)			\
+	do {								\
+		if (iscsi_dbg_lib)					\
+			iscsi_session_printk(KERN_INFO, _session,	\
+					     "%s " dbg_fmt,		\
+					     __func__, ##arg);		\
+	} while (0);
+
 /* Serial Number Arithmetic, 32 bits, less than, RFC1982 */
 #define SNA32_CHECK 2147483648UL
 
@@ -54,6 +76,15 @@ static int iscsi_sna_lte(u32 n1, u32 n2)
 			    (n1 > n2 && (n2 - n1 < SNA32_CHECK)));
 }
 
+inline void iscsi_conn_queue_work(struct iscsi_conn *conn)
+{
+	struct Scsi_Host *shost = conn->session->host;
+	struct iscsi_host *ihost = shost_priv(shost);
+
+	queue_work(ihost->workq, &conn->xmitwork);
+}
+EXPORT_SYMBOL_GPL(iscsi_conn_queue_work);
+
 void
 iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
 {
@@ -81,8 +112,7 @@ iscsi_update_cmdsn(struct iscsi_session *session, struct iscsi_nopin *hdr)
 		if (!list_empty(&session->leadconn->xmitqueue) ||
 		    !list_empty(&session->leadconn->mgmtqueue)) {
 			if (!(session->tt->caps & CAP_DATA_PATH_OFFLOAD))
-				scsi_queue_work(session->host,
-						&session->leadconn->xmitwork);
+				iscsi_conn_queue_work(session->leadconn);
 		}
 	}
 }
@@ -176,10 +206,11 @@ static int iscsi_prep_ecdb_ahs(struct iscsi_task *task)
 	ecdb_ahdr->reserved = 0;
 	memcpy(ecdb_ahdr->ecdb, cmd->cmnd + ISCSI_CDB_SIZE, rlen);
 
-	debug_scsi("iscsi_prep_ecdb_ahs: varlen_cdb_len %d "
-		   "rlen %d pad_len %d ahs_length %d iscsi_headers_size %u\n",
-		   cmd->cmd_len, rlen, pad_len, ahslength, task->hdr_len);
-
+	ISCSI_DBG_SESSION(task->conn->session,
+			  "iscsi_prep_ecdb_ahs: varlen_cdb_len %d "
+		          "rlen %d pad_len %d ahs_length %d iscsi_headers_size "
+		          "%u\n", cmd->cmd_len, rlen, pad_len, ahslength,
+		          task->hdr_len);
 	return 0;
 }
 
@@ -201,10 +232,11 @@ static int iscsi_prep_bidi_ahs(struct iscsi_task *task)
 	rlen_ahdr->reserved = 0;
 	rlen_ahdr->read_length = cpu_to_be32(scsi_in(sc)->length);
 
-	debug_scsi("bidi-in rlen_ahdr->read_length(%d) "
-		   "rlen_ahdr->ahslength(%d)\n",
-		   be32_to_cpu(rlen_ahdr->read_length),
-		   be16_to_cpu(rlen_ahdr->ahslength));
+	ISCSI_DBG_SESSION(task->conn->session,
+			  "bidi-in rlen_ahdr->read_length(%d) "
+		          "rlen_ahdr->ahslength(%d)\n",
+		          be32_to_cpu(rlen_ahdr->read_length),
+		          be16_to_cpu(rlen_ahdr->ahslength));
 	return 0;
 }
 
@@ -335,13 +367,15 @@ static int iscsi_prep_scsi_cmd_pdu(struct iscsi_task *task)
 	list_move_tail(&task->running, &conn->run_list);
 
 	conn->scsicmd_pdus_cnt++;
-	debug_scsi("iscsi prep [%s cid %d sc %p cdb 0x%x itt 0x%x len %d "
-		   "bidi_len %d cmdsn %d win %d]\n", scsi_bidi_cmnd(sc) ?
-		   "bidirectional" : sc->sc_data_direction == DMA_TO_DEVICE ?
-		   "write" : "read", conn->id, sc, sc->cmnd[0], task->itt,
-		   scsi_bufflen(sc),
-		   scsi_bidi_cmnd(sc) ? scsi_in(sc)->length : 0,
-		   session->cmdsn, session->max_cmdsn - session->exp_cmdsn + 1);
+	ISCSI_DBG_SESSION(session, "iscsi prep [%s cid %d sc %p cdb 0x%x "
+			  "itt 0x%x len %d bidi_len %d cmdsn %d win %d]\n",
+			  scsi_bidi_cmnd(sc) ? "bidirectional" :
+			  sc->sc_data_direction == DMA_TO_DEVICE ?
+			  "write" : "read", conn->id, sc, sc->cmnd[0],
+			  task->itt, scsi_bufflen(sc),
+			  scsi_bidi_cmnd(sc) ? scsi_in(sc)->length : 0,
+			  session->cmdsn,
+			  session->max_cmdsn - session->exp_cmdsn + 1);
 	return 0;
 }
 
@@ -483,9 +517,9 @@ static int iscsi_prep_mgmt_task(struct iscsi_conn *conn,
 
 	task->state = ISCSI_TASK_RUNNING;
 	list_move_tail(&task->running, &conn->mgmt_run_list);
-	debug_scsi("mgmtpdu [op 0x%x hdr->itt 0x%x datalen %d]\n",
-		   hdr->opcode & ISCSI_OPCODE_MASK, hdr->itt,
-		   task->data_count);
+	ISCSI_DBG_SESSION(session, "mgmtpdu [op 0x%x hdr->itt 0x%x "
+			  "datalen %d]\n", hdr->opcode & ISCSI_OPCODE_MASK,
+			  hdr->itt, task->data_count);
 	return 0;
 }
 
@@ -560,7 +594,7 @@ __iscsi_conn_send_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 			goto free_task;
 
 	} else
-		scsi_queue_work(conn->session->host, &conn->xmitwork);
+		iscsi_conn_queue_work(conn);
 
 	return task;
 
@@ -637,8 +671,9 @@ invalid_datalen:
 
 		memcpy(sc->sense_buffer, data + 2,
 		       min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
-		debug_scsi("copied %d bytes of sense\n",
-			   min_t(uint16_t, senselen, SCSI_SENSE_BUFFERSIZE));
+		ISCSI_DBG_SESSION(session, "copied %d bytes of sense\n",
+				  min_t(uint16_t, senselen,
+				  SCSI_SENSE_BUFFERSIZE));
 	}
 
 	if (rhdr->flags & (ISCSI_FLAG_CMD_BIDI_UNDERFLOW |
@@ -666,8 +701,8 @@ invalid_datalen:
 			sc->result = (DID_BAD_TARGET << 16) | rhdr->cmd_status;
 	}
 out:
-	debug_scsi("done [sc %lx res %d itt 0x%x]\n",
-		   (long)sc, sc->result, task->itt);
+	ISCSI_DBG_SESSION(session, "done [sc %p res %d itt 0x%x]\n",
+			  sc, sc->result, task->itt);
 	conn->scsirsp_pdus_cnt++;
 
 	__iscsi_put_task(task);
@@ -835,8 +870,8 @@ int __iscsi_complete_pdu(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
 	else
 		itt = ~0U;
 
-	debug_scsi("[op 0x%x cid %d itt 0x%x len %d]\n",
-		   opcode, conn->id, itt, datalen);
+	ISCSI_DBG_SESSION(session, "[op 0x%x cid %d itt 0x%x len %d]\n",
+			  opcode, conn->id, itt, datalen);
 
 	if (itt == ~0U) {
 		iscsi_update_cmdsn(session, (struct iscsi_nopin*)hdr);
@@ -1034,10 +1069,9 @@ struct iscsi_task *iscsi_itt_to_ctask(struct iscsi_conn *conn, itt_t itt)
 }
 EXPORT_SYMBOL_GPL(iscsi_itt_to_ctask);
 
-void iscsi_session_failure(struct iscsi_cls_session *cls_session,
+void iscsi_session_failure(struct iscsi_session *session,
 			   enum iscsi_err err)
 {
-	struct iscsi_session *session = cls_session->dd_data;
 	struct iscsi_conn *conn;
 	struct device *dev;
 	unsigned long flags;
@@ -1095,10 +1129,10 @@ static int iscsi_check_cmdsn_window_closed(struct iscsi_conn *conn)
 	 * Check for iSCSI window and take care of CmdSN wrap-around
 	 */
 	if (!iscsi_sna_lte(session->queued_cmdsn, session->max_cmdsn)) {
-		debug_scsi("iSCSI CmdSN closed. ExpCmdSn %u MaxCmdSN %u "
-			   "CmdSN %u/%u\n", session->exp_cmdsn,
-			   session->max_cmdsn, session->cmdsn,
-			   session->queued_cmdsn);
+		ISCSI_DBG_SESSION(session, "iSCSI CmdSN closed. ExpCmdSn "
+				  "%u MaxCmdSN %u CmdSN %u/%u\n",
+				  session->exp_cmdsn, session->max_cmdsn,
+				  session->cmdsn, session->queued_cmdsn);
 		return -ENOSPC;
 	}
 	return 0;
@@ -1133,7 +1167,7 @@ void iscsi_requeue_task(struct iscsi_task *task)
 	struct iscsi_conn *conn = task->conn;
 
 	list_move_tail(&task->running, &conn->requeue);
-	scsi_queue_work(conn->session->host, &conn->xmitwork);
+	iscsi_conn_queue_work(conn);
 }
 EXPORT_SYMBOL_GPL(iscsi_requeue_task);
 
@@ -1152,7 +1186,7 @@ static int iscsi_data_xmit(struct iscsi_conn *conn)
 
 	spin_lock_bh(&conn->session->lock);
 	if (unlikely(conn->suspend_tx)) {
-		debug_scsi("conn %d Tx suspended!\n", conn->id);
+		ISCSI_DBG_SESSION(conn->session, "Tx suspended!\n");
 		spin_unlock_bh(&conn->session->lock);
 		return -ENODATA;
 	}
@@ -1386,7 +1420,7 @@ int iscsi_queuecommand(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
 			goto prepd_reject;
 		}
 	} else
-		scsi_queue_work(session->host, &conn->xmitwork);
+		iscsi_conn_queue_work(conn);
 
 	session->queued_cmdsn++;
 	spin_unlock(&session->lock);
@@ -1398,7 +1432,8 @@ prepd_reject:
 	iscsi_complete_command(task);
 reject:
 	spin_unlock(&session->lock);
-	debug_scsi("cmd 0x%x rejected (%d)\n", sc->cmnd[0], reason);
+	ISCSI_DBG_SESSION(session, "cmd 0x%x rejected (%d)\n",
+			  sc->cmnd[0], reason);
 	spin_lock(host->host_lock);
 	return SCSI_MLQUEUE_TARGET_BUSY;
 
@@ -1407,7 +1442,8 @@ prepd_fault:
 	iscsi_complete_command(task);
 fault:
 	spin_unlock(&session->lock);
-	debug_scsi("iscsi: cmd 0x%x is not queued (%d)\n", sc->cmnd[0], reason);
+	ISCSI_DBG_SESSION(session, "iscsi: cmd 0x%x is not queued (%d)\n",
+			  sc->cmnd[0], reason);
 	if (!scsi_bidi_cmnd(sc))
 		scsi_set_resid(sc, scsi_bufflen(sc));
 	else {
@@ -1422,8 +1458,6 @@ EXPORT_SYMBOL_GPL(iscsi_queuecommand);
 
 int iscsi_change_queue_depth(struct scsi_device *sdev, int depth)
 {
-	if (depth > ISCSI_MAX_CMD_PER_LUN)
-		depth = ISCSI_MAX_CMD_PER_LUN;
 	scsi_adjust_queue_depth(sdev, scsi_get_tag_type(sdev), depth);
 	return sdev->queue_depth;
 }
@@ -1457,8 +1491,10 @@ int iscsi_eh_target_reset(struct scsi_cmnd *sc)
 	spin_lock_bh(&session->lock);
 	if (session->state == ISCSI_STATE_TERMINATE) {
 failed:
-		debug_scsi("failing target reset: session terminated "
-			   "[CID %d age %d]\n", conn->id, session->age);
+		iscsi_session_printk(KERN_INFO, session,
+				     "failing target reset: Could not log "
+				     "back into target [age %d]\n",
+				     session->age);
 		spin_unlock_bh(&session->lock);
 		mutex_unlock(&session->eh_mutex);
 		return FAILED;
@@ -1472,7 +1508,7 @@ failed:
 	 */
 	iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
 
-	debug_scsi("iscsi_eh_target_reset wait for relogin\n");
+	ISCSI_DBG_SESSION(session, "wait for relogin\n");
 	wait_event_interruptible(conn->ehwait,
 				 session->state == ISCSI_STATE_TERMINATE ||
 				 session->state == ISCSI_STATE_LOGGED_IN ||
@@ -1501,7 +1537,7 @@ static void iscsi_tmf_timedout(unsigned long data)
 	spin_lock(&session->lock);
 	if (conn->tmf_state == TMF_QUEUED) {
 		conn->tmf_state = TMF_TIMEDOUT;
-		debug_scsi("tmf timedout\n");
+		ISCSI_DBG_SESSION(session, "tmf timedout\n");
 		/* unblock eh_abort() */
 		wake_up(&conn->ehwait);
 	}
@@ -1521,7 +1557,7 @@ static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
 		spin_unlock_bh(&session->lock);
 		iscsi_conn_failure(conn, ISCSI_ERR_CONN_FAILED);
 		spin_lock_bh(&session->lock);
-		debug_scsi("tmf exec failure\n");
+		ISCSI_DBG_SESSION(session, "tmf exec failure\n");
 		return -EPERM;
 	}
 	conn->tmfcmd_pdus_cnt++;
@@ -1529,7 +1565,7 @@ static int iscsi_exec_task_mgmt_fn(struct iscsi_conn *conn,
 	conn->tmf_timer.function = iscsi_tmf_timedout;
 	conn->tmf_timer.data = (unsigned long)conn;
 	add_timer(&conn->tmf_timer);
-	debug_scsi("tmf set timeout\n");
+	ISCSI_DBG_SESSION(session, "tmf set timeout\n");
 
 	spin_unlock_bh(&session->lock);
 	mutex_unlock(&session->eh_mutex);
@@ -1567,22 +1603,27 @@ static void fail_all_commands(struct iscsi_conn *conn, unsigned lun,
 {
 	struct iscsi_task *task, *tmp;
 
-	if (conn->task && (conn->task->sc->device->lun == lun || lun == -1))
-		conn->task = NULL;
+	if (conn->task) {
+		if (lun == -1 ||
+		    (conn->task->sc && conn->task->sc->device->lun == lun))
+			conn->task = NULL;
+	}
 
 	/* flush pending */
 	list_for_each_entry_safe(task, tmp, &conn->xmitqueue, running) {
 		if (lun == task->sc->device->lun || lun == -1) {
-			debug_scsi("failing pending sc %p itt 0x%x\n",
-				   task->sc, task->itt);
+			ISCSI_DBG_SESSION(conn->session,
+					  "failing pending sc %p itt 0x%x\n",
+					  task->sc, task->itt);
 			fail_command(conn, task, error << 16);
 		}
 	}
 
 	list_for_each_entry_safe(task, tmp, &conn->requeue, running) {
 		if (lun == task->sc->device->lun || lun == -1) {
-			debug_scsi("failing requeued sc %p itt 0x%x\n",
-				   task->sc, task->itt);
+			ISCSI_DBG_SESSION(conn->session,
+					  "failing requeued sc %p itt 0x%x\n",
+					  task->sc, task->itt);
 			fail_command(conn, task, error << 16);
 		}
 	}
@@ -1590,8 +1631,9 @@ static void fail_all_commands(struct iscsi_conn *conn, unsigned lun,
 	/* fail all other running */
 	list_for_each_entry_safe(task, tmp, &conn->run_list, running) {
 		if (lun == task->sc->device->lun || lun == -1) {
-			debug_scsi("failing in progress sc %p itt 0x%x\n",
-				   task->sc, task->itt);
+			ISCSI_DBG_SESSION(conn->session,
+					 "failing in progress sc %p itt 0x%x\n",
+					 task->sc, task->itt);
 			fail_command(conn, task, error << 16);
 		}
 	}
@@ -1599,9 +1641,12 @@ static void fail_all_commands(struct iscsi_conn *conn, unsigned lun,
 
 void iscsi_suspend_tx(struct iscsi_conn *conn)
 {
+	struct Scsi_Host *shost = conn->session->host;
+	struct iscsi_host *ihost = shost_priv(shost);
+
 	set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
 	if (!(conn->session->tt->caps & CAP_DATA_PATH_OFFLOAD))
-		scsi_flush_work(conn->session->host);
+		flush_workqueue(ihost->workq);
 }
 EXPORT_SYMBOL_GPL(iscsi_suspend_tx);
 
@@ -1609,7 +1654,7 @@ static void iscsi_start_tx(struct iscsi_conn *conn)
 {
 	clear_bit(ISCSI_SUSPEND_BIT, &conn->suspend_tx);
 	if (!(conn->session->tt->caps & CAP_DATA_PATH_OFFLOAD))
-		scsi_queue_work(conn->session->host, &conn->xmitwork);
+		iscsi_conn_queue_work(conn);
 }
 
 static enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
@@ -1622,7 +1667,7 @@ static enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
 	cls_session = starget_to_session(scsi_target(scmd->device));
 	session = cls_session->dd_data;
 
-	debug_scsi("scsi cmd %p timedout\n", scmd);
+	ISCSI_DBG_SESSION(session, "scsi cmd %p timedout\n", scmd);
 
 	spin_lock(&session->lock);
 	if (session->state != ISCSI_STATE_LOGGED_IN) {
@@ -1662,8 +1707,8 @@ static enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
 		rc = BLK_EH_RESET_TIMER;
 done:
 	spin_unlock(&session->lock);
-	debug_scsi("return %s\n", rc == BLK_EH_RESET_TIMER ?
-					"timer reset" : "nh");
+	ISCSI_DBG_SESSION(session, "return %s\n", rc == BLK_EH_RESET_TIMER ?
+			  "timer reset" : "nh");
 	return rc;
 }
 
@@ -1697,13 +1742,13 @@ static void iscsi_check_transport_timeouts(unsigned long data)
 
 	if (time_before_eq(last_recv + recv_timeout, jiffies)) {
 		/* send a ping to try to provoke some traffic */
-		debug_scsi("Sending nopout as ping on conn %p\n", conn);
+		ISCSI_DBG_CONN(conn, "Sending nopout as ping\n");
 		iscsi_send_nopout(conn, NULL);
 		next_timeout = conn->last_ping + (conn->ping_timeout * HZ);
 	} else
 		next_timeout = last_recv + recv_timeout;
 
-	debug_scsi("Setting next tmo %lu\n", next_timeout);
+	ISCSI_DBG_CONN(conn, "Setting next tmo %lu\n", next_timeout);
 	mod_timer(&conn->transport_timer, next_timeout);
 done:
 	spin_unlock(&session->lock);
@@ -1740,7 +1785,8 @@ int iscsi_eh_abort(struct scsi_cmnd *sc)
 	 * got the command.
 	 */
 	if (!sc->SCp.ptr) {
-		debug_scsi("sc never reached iscsi layer or it completed.\n");
+		ISCSI_DBG_SESSION(session, "sc never reached iscsi layer or "
+				  "it completed.\n");
 		spin_unlock_bh(&session->lock);
 		mutex_unlock(&session->eh_mutex);
 		return SUCCESS;
@@ -1762,11 +1808,13 @@ int iscsi_eh_abort(struct scsi_cmnd *sc)
 	age = session->age;
 
 	task = (struct iscsi_task *)sc->SCp.ptr;
-	debug_scsi("aborting [sc %p itt 0x%x]\n", sc, task->itt);
+	ISCSI_DBG_SESSION(session, "aborting [sc %p itt 0x%x]\n",
+			  sc, task->itt);
 
 	/* task completed before time out */
 	if (!task->sc) {
-		debug_scsi("sc completed while abort in progress\n");
+		ISCSI_DBG_SESSION(session, "sc completed while abort in "
+				  "progress\n");
 		goto success;
 	}
 
@@ -1815,7 +1863,8 @@ int iscsi_eh_abort(struct scsi_cmnd *sc)
 		if (!sc->SCp.ptr) {
 			conn->tmf_state = TMF_INITIAL;
 			/* task completed before tmf abort response */
-			debug_scsi("sc completed while abort in progress\n");
+			ISCSI_DBG_SESSION(session, "sc completed while abort "
+					  "in progress\n");
 			goto success;
 		}
 		/* fall through */
@@ -1827,15 +1876,16 @@ int iscsi_eh_abort(struct scsi_cmnd *sc)
 success:
 	spin_unlock_bh(&session->lock);
 success_unlocked:
-	debug_scsi("abort success [sc %lx itt 0x%x]\n", (long)sc, task->itt);
+	ISCSI_DBG_SESSION(session, "abort success [sc %p itt 0x%x]\n",
+			  sc, task->itt);
 	mutex_unlock(&session->eh_mutex);
 	return SUCCESS;
 
 failed:
 	spin_unlock_bh(&session->lock);
 failed_unlocked:
-	debug_scsi("abort failed [sc %p itt 0x%x]\n", sc,
-		    task ? task->itt : 0);
+	ISCSI_DBG_SESSION(session, "abort failed [sc %p itt 0x%x]\n", sc,
+			  task ? task->itt : 0);
 	mutex_unlock(&session->eh_mutex);
 	return FAILED;
 }
@@ -1862,7 +1912,8 @@ int iscsi_eh_device_reset(struct scsi_cmnd *sc)
 	cls_session = starget_to_session(scsi_target(sc->device));
 	session = cls_session->dd_data;
 
-	debug_scsi("LU Reset [sc %p lun %u]\n", sc, sc->device->lun);
+	ISCSI_DBG_SESSION(session, "LU Reset [sc %p lun %u]\n",
+			  sc, sc->device->lun);
 
 	mutex_lock(&session->eh_mutex);
 	spin_lock_bh(&session->lock);
@@ -1916,8 +1967,8 @@ int iscsi_eh_device_reset(struct scsi_cmnd *sc)
 unlock:
 	spin_unlock_bh(&session->lock);
 done:
-	debug_scsi("iscsi_eh_device_reset %s\n",
-		  rc == SUCCESS ? "SUCCESS" : "FAILED");
+	ISCSI_DBG_SESSION(session, "dev reset result = %s\n",
+			 rc == SUCCESS ? "SUCCESS" : "FAILED");
 	mutex_unlock(&session->eh_mutex);
 	return rc;
 }
@@ -1944,7 +1995,7 @@ iscsi_pool_init(struct iscsi_pool *q, int max, void ***items, int item_size)
 		num_arrays++;
 	q->pool = kzalloc(num_arrays * max * sizeof(void*), GFP_KERNEL);
 	if (q->pool == NULL)
-		goto enomem;
+		return -ENOMEM;
 
 	q->queue = kfifo_init((void*)q->pool, max * sizeof(void*),
 			      GFP_KERNEL, NULL);
@@ -1979,8 +2030,7 @@ void iscsi_pool_free(struct iscsi_pool *q)
 
 	for (i = 0; i < q->max; i++)
 		kfree(q->pool[i]);
-	if (q->pool)
-		kfree(q->pool);
+	kfree(q->pool);
 	kfree(q->queue);
 }
 EXPORT_SYMBOL_GPL(iscsi_pool_free);
@@ -1998,6 +2048,9 @@ int iscsi_host_add(struct Scsi_Host *shost, struct device *pdev)
 	if (!shost->can_queue)
 		shost->can_queue = ISCSI_DEF_XMIT_CMDS_MAX;
 
+	if (!shost->cmd_per_lun)
+		shost->cmd_per_lun = ISCSI_DEF_CMD_PER_LUN;
+
 	if (!shost->transportt->eh_timed_out)
 		shost->transportt->eh_timed_out = iscsi_eh_cmd_timed_out;
 	return scsi_add_host(shost, pdev);
@@ -2008,13 +2061,13 @@ EXPORT_SYMBOL_GPL(iscsi_host_add);
  * iscsi_host_alloc - allocate a host and driver data
  * @sht: scsi host template
  * @dd_data_size: driver host data size
- * @qdepth: default device queue depth
+ * @xmit_can_sleep: bool indicating if LLD will queue IO from a work queue
  *
  * This should be called by partial offload and software iscsi drivers.
  * To access the driver specific memory use the iscsi_host_priv() macro.
  */
 struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
-				   int dd_data_size, uint16_t qdepth)
+				   int dd_data_size, bool xmit_can_sleep)
 {
 	struct Scsi_Host *shost;
 	struct iscsi_host *ihost;
@@ -2022,28 +2075,31 @@ struct Scsi_Host *iscsi_host_alloc(struct scsi_host_template *sht,
 	shost = scsi_host_alloc(sht, sizeof(struct iscsi_host) + dd_data_size);
 	if (!shost)
 		return NULL;
+	ihost = shost_priv(shost);
 
-	if (qdepth > ISCSI_MAX_CMD_PER_LUN || qdepth < 1) {
-		if (qdepth != 0)
-			printk(KERN_ERR "iscsi: invalid queue depth of %d. "
-			       "Queue depth must be between 1 and %d.\n",
-			       qdepth, ISCSI_MAX_CMD_PER_LUN);
-		qdepth = ISCSI_DEF_CMD_PER_LUN;
+	if (xmit_can_sleep) {
+		snprintf(ihost->workq_name, sizeof(ihost->workq_name),
+			"iscsi_q_%d", shost->host_no);
+		ihost->workq = create_singlethread_workqueue(ihost->workq_name);
+		if (!ihost->workq)
+			goto free_host;
 	}
-	shost->cmd_per_lun = qdepth;
 
-	ihost = shost_priv(shost);
 	spin_lock_init(&ihost->lock);
 	ihost->state = ISCSI_HOST_SETUP;
 	ihost->num_sessions = 0;
 	init_waitqueue_head(&ihost->session_removal_wq);
 	return shost;
+
+free_host:
+	scsi_host_put(shost);
+	return NULL;
 }
 EXPORT_SYMBOL_GPL(iscsi_host_alloc);
 
 static void iscsi_notify_host_removed(struct iscsi_cls_session *cls_session)
 {
-	iscsi_session_failure(cls_session, ISCSI_ERR_INVALID_HOST);
+	iscsi_session_failure(cls_session->dd_data, ISCSI_ERR_INVALID_HOST);
 }
 
 /**
@@ -2069,6 +2125,8 @@ void iscsi_host_remove(struct Scsi_Host *shost)
 		flush_signals(current);
 
 	scsi_remove_host(shost);
+	if (ihost->workq)
+		destroy_workqueue(ihost->workq);
 }
 EXPORT_SYMBOL_GPL(iscsi_host_remove);
 
@@ -2467,14 +2525,16 @@ flush_control_queues(struct iscsi_session *session, struct iscsi_conn *conn)
 
 	/* handle pending */
 	list_for_each_entry_safe(task, tmp, &conn->mgmtqueue, running) {
-		debug_scsi("flushing pending mgmt task itt 0x%x\n", task->itt);
+		ISCSI_DBG_SESSION(session, "flushing pending mgmt task "
+				  "itt 0x%x\n", task->itt);
 		/* release ref from prep task */
 		__iscsi_put_task(task);
 	}
 
 	/* handle running */
 	list_for_each_entry_safe(task, tmp, &conn->mgmt_run_list, running) {
-		debug_scsi("flushing running mgmt task itt 0x%x\n", task->itt);
+		ISCSI_DBG_SESSION(session, "flushing running mgmt task "
+				  "itt 0x%x\n", task->itt);
 		/* release ref from prep task */
 		__iscsi_put_task(task);
 	}
@@ -2524,7 +2584,7 @@ static void iscsi_start_session_recovery(struct iscsi_session *session,
 		conn->datadgst_en = 0;
 		if (session->state == ISCSI_STATE_IN_RECOVERY &&
 		    old_stop_stage != STOP_CONN_RECOVER) {
-			debug_scsi("blocking session\n");
+			ISCSI_DBG_SESSION(session, "blocking session\n");
 			iscsi_block_session(session->cls_session);
 		}
 	}