[PATCH 23/40] scsi: libiscsi: remove ISCSI_TASK_REQUEUE_SCSIQ

[Mike Christie <michael.christie@xxxxxxxxxx>]

ISCSI_TASK_REQUEUE_SCSIQ is just kind of awkward and it's wrong. If in
queuecommand we are going to return SCSI_MLQUEUE_TARGET_BUSY then we
must have finished up cleaning up the cmd when queuecommand returns.
This has us call the final cleanup code directly. Because the cmd was
allocated by the block/scsi layer and we've been under the frwd lock the
entire time, we know that nothing else has a ref to the cmd and we can
just call the free function directly.

Signed-off-by: Mike Christie <michael.christie@xxxxxxxxxx>
---
 drivers/scsi/libiscsi.c | 39 +++++++++++++++++++++------------------
 include/scsi/libiscsi.h |  1 -
 2 files changed, 21 insertions(+), 19 deletions(-)

diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
index e2f3217afdc9..00a25af9eb98 100644
--- a/drivers/scsi/libiscsi.c
+++ b/drivers/scsi/libiscsi.c
@@ -437,19 +437,18 @@ static int iscsi_prep_scsi_cmd_pdu(struct iscsi_task *task)
 }
 
 /**
- * iscsi_free_task - free a task
+ * __iscsi_free_task - free a task
  * @task: iscsi cmd task
  *
  * Must be called with session back_lock.
  * This function returns the scsi command to scsi-ml or cleans
  * up mgmt tasks then returns the task to the pool.
  */
-static void iscsi_free_task(struct iscsi_task *task)
+static void __iscsi_free_task(struct iscsi_task *task)
 {
 	struct iscsi_conn *conn = task->conn;
 	struct iscsi_session *session = conn->session;
 	struct scsi_cmnd *sc = task->sc;
-	int oldstate = task->state;
 
 	ISCSI_DBG_SESSION(session, "freeing task itt 0x%x state %d sc %p\n",
 			  task->itt, task->state, task->sc);
@@ -463,18 +462,21 @@ static void iscsi_free_task(struct iscsi_task *task)
 	if (conn->login_task == task)
 		return;
 
-	if (!sc) {
+	if (!sc)
 		kfifo_in(&session->mgmt_pool.queue, (void *)&task, sizeof(void *));
-	} else {
-		/* SCSI eh reuses commands to verify us */
-		sc->SCp.ptr = NULL;
-		/*
-		 * queue command may call this to free the task, so
-		 * it will decide how to return sc to scsi-ml.
-		 */
-		if (oldstate != ISCSI_TASK_REQUEUE_SCSIQ)
-			sc->scsi_done(sc);
-	}
+}
+
+static void iscsi_free_task(struct iscsi_task *task)
+{
+	struct scsi_cmnd *sc = task->sc;
+
+	__iscsi_free_task(task);
+	if (!sc)
+		return;
+
+	/* SCSI eh reuses commands to verify us */
+	sc->SCp.ptr = NULL;
+	sc->scsi_done(sc);
 }
 
 void __iscsi_get_task(struct iscsi_task *task)
@@ -516,8 +518,7 @@ static void iscsi_finish_task(struct iscsi_task *task, int state)
 			  "complete task itt 0x%x state %d sc %p\n",
 			  task->itt, task->state, task->sc);
 	if (task->state == ISCSI_TASK_COMPLETED ||
-	    task->state == ISCSI_TASK_ABRT_TMF ||
-	    task->state == ISCSI_TASK_REQUEUE_SCSIQ)
+	    task->state == ISCSI_TASK_ABRT_TMF)
 		return;
 	WARN_ON_ONCE(task->state == ISCSI_TASK_FREE);
 	task->state = state;
@@ -1844,7 +1845,7 @@ int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc)
 	spin_unlock_bh(&session->frwd_lock);
 
 	spin_lock_bh(&session->back_lock);
-	iscsi_finish_task(task, ISCSI_TASK_REQUEUE_SCSIQ);
+	__iscsi_free_task(task);
 	spin_unlock_bh(&session->back_lock);
 reject:
 	ISCSI_DBG_SESSION(session, "cmd 0x%x rejected (%d)\n",
@@ -1855,8 +1856,10 @@ int iscsi_queuecommand(struct Scsi_Host *host, struct scsi_cmnd *sc)
 	spin_unlock_bh(&session->frwd_lock);
 
 	spin_lock_bh(&session->back_lock);
-	iscsi_finish_task(task, ISCSI_TASK_REQUEUE_SCSIQ);
+	iscsi_finish_task(task, ISCSI_TASK_COMPLETED);
 	spin_unlock_bh(&session->back_lock);
+	return 0;
+
 fault:
 	ISCSI_DBG_SESSION(session, "iscsi: cmd 0x%x is not queued (%d)\n",
 			  sc->cmnd[0], reason);
diff --git a/include/scsi/libiscsi.h b/include/scsi/libiscsi.h
index 589acc1d420d..ceb01ef12002 100644
--- a/include/scsi/libiscsi.h
+++ b/include/scsi/libiscsi.h
@@ -97,7 +97,6 @@ enum {
 	ISCSI_TASK_PENDING,
 	ISCSI_TASK_RUNNING,
 	ISCSI_TASK_ABRT_TMF,		/* aborted due to TMF */
-	ISCSI_TASK_REQUEUE_SCSIQ,	/* qcmd requeueing to scsi-ml */
 };
 
 struct iscsi_r2t_info {
-- 
2.25.1