tcm_qla2xxx: Offload WRITE I/O backend submission to tcm_qla2xxx wq

Defer the whole tcm_qla2xxx_handle_data call instead of just the error
path to the qla2xxx-internal workqueue.  Also remove the useless lock around
the CMD_T_ABORTED check.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Giridhar Malavali <giridhar.malavali@qlogic.com>
Cc: tcm-qla2xxx@qlogic.com
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

1 files changed, 18 insertions, 28 deletions

diff --git a/drivers/scsi/qla2xxx/tcm_qla2xxx.c b/drivers/scsi/qla2xxx/tcm_qla2xxx.c
index dd0a0dfd6e4..977cb8b1e42 100644
--- a/drivers/scsi/qla2xxx/tcm_qla2xxx.c
+++ b/drivers/scsi/qla2xxx/tcm_qla2xxx.c
@@ -604,22 +604,10 @@ static int tcm_qla2xxx_handle_cmd(scsi_qla_host_t *vha, struct qla_tgt_cmd *cmd,
         return 0;
 }
 
-static void tcm_qla2xxx_do_rsp(struct work_struct *work)
+static void tcm_qla2xxx_handle_data_work(struct work_struct *work)
 {
         struct qla_tgt_cmd *cmd = container_of(work, struct qla_tgt_cmd, work);
-        /*
-         * Dispatch ->queue_status from workqueue process context
-         */
-        transport_generic_request_failure(&cmd->se_cmd);
-}
 
-/*
- * Called from qla_target.c:qlt_do_ctio_completion()
- */
-static int tcm_qla2xxx_handle_data(struct qla_tgt_cmd *cmd)
-{
-        struct se_cmd *se_cmd = &cmd->se_cmd;
-        unsigned long flags;
         /*
          * Ensure that the complete FCP WRITE payload has been received.
          * Otherwise return an exception via CHECK_CONDITION status.
@@ -629,24 +617,26 @@ static int tcm_qla2xxx_handle_data(struct qla_tgt_cmd *cmd)
                  * Check if se_cmd has already been aborted via LUN_RESET, and
                  * waiting upon completion in tcm_qla2xxx_write_pending_status()
                  */
-                spin_lock_irqsave(&se_cmd->t_state_lock, flags);
-                if (se_cmd->transport_state & CMD_T_ABORTED) {
-                        spin_unlock_irqrestore(&se_cmd->t_state_lock, flags);
-                        complete(&se_cmd->t_transport_stop_comp);
-                        return 0;
+                if (cmd->se_cmd.transport_state & CMD_T_ABORTED) {
+                        complete(&cmd->se_cmd.t_transport_stop_comp);
+                        return;
                 }
-                spin_unlock_irqrestore(&se_cmd->t_state_lock, flags);
 
-                se_cmd->scsi_sense_reason = TCM_CHECK_CONDITION_ABORT_CMD;
-                INIT_WORK(&cmd->work, tcm_qla2xxx_do_rsp);
-                queue_work(tcm_qla2xxx_free_wq, &cmd->work);
-                return 0;
+                cmd->se_cmd.scsi_sense_reason = TCM_CHECK_CONDITION_ABORT_CMD;
+                transport_generic_request_failure(&cmd->se_cmd);
+                return;
         }
-        /*
-         * We now tell TCM to queue this WRITE CDB with TRANSPORT_PROCESS_WRITE
-         * status to the backstore processing thread.
-         */
-        return transport_generic_handle_data(&cmd->se_cmd);
+
+        return target_execute_cmd(&cmd->se_cmd);
+}
+
+/*
+ * Called from qla_target.c:qlt_do_ctio_completion()
+ */
+static void tcm_qla2xxx_handle_data(struct qla_tgt_cmd *cmd)
+{
+        INIT_WORK(&cmd->work, tcm_qla2xxx_handle_data_work);
+        queue_work(tcm_qla2xxx_free_wq, &cmd->work);
 }
 
 /*