[PATCH 01/11] libiscsi: Convert to host_lock less w/ interrupts disabled internally

["Nicholas A. Bellinger" <nab@linux-iscsi.org>]

From: Nicholas Bellinger <nab@linux-iscsi.org>

This patch changes iscsi_queuecommand_lck() to a host_lock less
iscsi_queuecommand() that will internally disable interrupts using
session->lock and drop the now legacy host_lock unlock.

Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
---
 drivers/scsi/libiscsi.c |   19 +++++++------------
 1 files changed, 7 insertions(+), 12 deletions(-)

diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
index c15fde8..499f837 100644
--- a/drivers/scsi/libiscsi.c
+++ b/drivers/scsi/libiscsi.c
@@ -1599,7 +1599,7 @@ enum {
 	FAILURE_SESSION_NOT_READY,
 };
 
-static int iscsi_queuecommand_lck(struct scsi_cmnd *sc, void (*done)(struct scsi_cmnd *))
+int iscsi_queuecommand(struct Scsi_Host *sh, struct scsi_cmnd *sc)
 {
 	struct iscsi_cls_session *cls_session;
 	struct Scsi_Host *host;
@@ -1608,18 +1608,17 @@ static int iscsi_queuecommand_lck(struct scsi_cmnd *sc, void (*done)(struct scsi
 	struct iscsi_session *session;
 	struct iscsi_conn *conn;
 	struct iscsi_task *task = NULL;
+	unsigned long irq_flags;
 
-	sc->scsi_done = done;
 	sc->result = 0;
 	sc->SCp.ptr = NULL;
 
 	host = sc->device->host;
 	ihost = shost_priv(host);
-	spin_unlock(host->host_lock);
 
 	cls_session = starget_to_session(scsi_target(sc->device));
 	session = cls_session->dd_data;
-	spin_lock(&session->lock);
+	spin_lock_irqsave(&session->lock, irq_flags);
 
 	reason = iscsi_session_chkready(cls_session);
 	if (reason) {
@@ -1705,25 +1704,23 @@ static int iscsi_queuecommand_lck(struct scsi_cmnd *sc, void (*done)(struct scsi
 	}
 
 	session->queued_cmdsn++;
-	spin_unlock(&session->lock);
-	spin_lock(host->host_lock);
+	spin_unlock_irqrestore(&session->lock, irq_flags);
 	return 0;
 
 prepd_reject:
 	sc->scsi_done = NULL;
 	iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
 reject:
-	spin_unlock(&session->lock);
+	spin_unlock_irqrestore(&session->lock, irq_flags);
 	ISCSI_DBG_SESSION(session, "cmd 0x%x rejected (%d)\n",
 			  sc->cmnd[0], reason);
-	spin_lock(host->host_lock);
 	return SCSI_MLQUEUE_TARGET_BUSY;
 
 prepd_fault:
 	sc->scsi_done = NULL;
 	iscsi_complete_task(task, ISCSI_TASK_COMPLETED);
 fault:
-	spin_unlock(&session->lock);
+	spin_unlock_irqrestore(&session->lock, irq_flags);
 	ISCSI_DBG_SESSION(session, "iscsi: cmd 0x%x is not queued (%d)\n",
 			  sc->cmnd[0], reason);
 	if (!scsi_bidi_cmnd(sc))
@@ -1732,12 +1729,10 @@ fault:
 		scsi_out(sc)->resid = scsi_out(sc)->length;
 		scsi_in(sc)->resid = scsi_in(sc)->length;
 	}
-	done(sc);
-	spin_lock(host->host_lock);
+	sc->scsi_done(sc);
 	return 0;
 }
 
-DEF_SCSI_QCMD(iscsi_queuecommand)
 EXPORT_SYMBOL_GPL(iscsi_queuecommand);
 
 int iscsi_change_queue_depth(struct scsi_device *sdev, int depth, int reason)
-- 
1.7.2.3