target: Push target_submit_tmr LUN lookup failure to system_wq context

In order to handle incoming target_submit_tmr() callers using interrupt
context, use system_wq process context for transport_lookup_tmr_lun()
failures to return TMR_LUN_DOES_NOT_EXIST status for fabric TM response.

Cc: Andy Grover <agrover@redhat.com>
Cc: Kiran Patil <kiran.patil@intel.com>
Cc: Arun Easi <arun.easi@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

1 files changed, 15 insertions, 3 deletions

diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
index 96e78f3f461d..ca1a40dc4888 100644
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c
@@ -1694,6 +1694,15 @@ void target_submit_cmd(struct se_cmd *se_cmd, struct se_session *se_sess,
 }
 EXPORT_SYMBOL(target_submit_cmd);
 
+static void target_complete_tmr_failure(struct work_struct *work)
+{
+        struct se_cmd *se_cmd = container_of(work, struct se_cmd, work);
+
+        se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
+        se_cmd->se_tfo->queue_tm_rsp(se_cmd);
+        transport_generic_free_cmd(se_cmd, 0);
+}
+
 /**
  * target_submit_tmr - lookup unpacked lun and submit uninitialized se_cmd
  *                     for TMR CDBs
@@ -1734,9 +1743,12 @@ int target_submit_tmr(struct se_cmd *se_cmd, struct se_session *se_sess,
 
         ret = transport_lookup_tmr_lun(se_cmd, unpacked_lun);
         if (ret) {
-                se_cmd->se_tmr_req->response = TMR_LUN_DOES_NOT_EXIST;
-                se_cmd->se_tfo->queue_tm_rsp(se_cmd);
-                transport_generic_free_cmd(se_cmd, 0);
+                /*
+                 * For callback during failure handling, push this work off
+                 * to process context with TMR_LUN_DOES_NOT_EXIST status.
+                 */
+                INIT_WORK(&se_cmd->work, target_complete_tmr_failure);
+                schedule_work(&se_cmd->work);
                 return 0;
         }
         transport_generic_handle_tmr(se_cmd);