block: unify request timeout handling

Right now SCSI and others do their own command timeout handling.
Move those bits to the block layer.

Instead of having a timer per command, we try to be a bit more clever
and simply have one per-queue. This avoids the overhead of having to
tear down and setup a timer for each command, so it will result in a lot
less timer fiddling.

Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

1 files changed, 9 insertions, 8 deletions

diff --git a/drivers/scsi/libiscsi.c b/drivers/scsi/libiscsi.c
index 299e075a7b34..1eca82420aab 100644
--- a/drivers/scsi/libiscsi.c
+++ b/drivers/scsi/libiscsi.c
@@ -1476,12 +1476,12 @@ static void iscsi_start_tx(struct iscsi_conn *conn)
                 scsi_queue_work(conn->session->host, &conn->xmitwork);
 }
 
-static enum scsi_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
+static enum blk_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
 {
         struct iscsi_cls_session *cls_session;
         struct iscsi_session *session;
         struct iscsi_conn *conn;
-        enum scsi_eh_timer_return rc = EH_NOT_HANDLED;
+        enum blk_eh_timer_return rc = BLK_EH_NOT_HANDLED;
 
         cls_session = starget_to_session(scsi_target(scmd->device));
         session = cls_session->dd_data;
@@ -1494,14 +1494,14 @@ static enum scsi_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
                  * We are probably in the middle of iscsi recovery so let
                  * that complete and handle the error.
                  */
-                rc = EH_RESET_TIMER;
+                rc = BLK_EH_RESET_TIMER;
                 goto done;
         }
 
         conn = session->leadconn;
         if (!conn) {
                 /* In the middle of shuting down */
-                rc = EH_RESET_TIMER;
+                rc = BLK_EH_RESET_TIMER;
                 goto done;
         }
 
@@ -1513,20 +1513,21 @@ static enum scsi_eh_timer_return iscsi_eh_cmd_timed_out(struct scsi_cmnd *scmd)
          */
         if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ) +
                             (conn->ping_timeout * HZ), jiffies))
-                rc = EH_RESET_TIMER;
+                rc = BLK_EH_RESET_TIMER;
         /*
          * if we are about to check the transport then give the command
          * more time
          */
         if (time_before_eq(conn->last_recv + (conn->recv_timeout * HZ),
                            jiffies))
-                rc = EH_RESET_TIMER;
+                rc = BLK_EH_RESET_TIMER;
         /* if in the middle of checking the transport then give us more time */
         if (conn->ping_task)
-                rc = EH_RESET_TIMER;
+                rc = BLK_EH_RESET_TIMER;
 done:
         spin_unlock(&session->lock);
-        debug_scsi("return %s\n", rc == EH_RESET_TIMER ? "timer reset" : "nh");
+        debug_scsi("return %s\n", rc == BLK_EH_RESET_TIMER ?
+                                        "timer reset" : "nh");
         return rc;
 }