[SCSI] remove a useless get/put_device pair in scsi_requeue_command

Avoid a spurious device get/put pair by cleaning up scsi_requeue_command
and folding scsi_unprep_request into it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index eba8044d0b112627a22944cf3a92a5d63eb3c91c..5681c05ac5061bc0050c3926cc3b7f300cef712b 100644 (file)
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -75,29 +75,6 @@ struct kmem_cache *scsi_sdb_cache;
  */
 #define SCSI_QUEUE_DELAY       3
 
-/*
- * Function:   scsi_unprep_request()
- *
- * Purpose:    Remove all preparation done for a request, including its
- *             associated scsi_cmnd, so that it can be requeued.
- *
- * Arguments:  req     - request to unprepare
- *
- * Lock status:        Assumed that no locks are held upon entry.
- *
- * Returns:    Nothing.
- */
-static void scsi_unprep_request(struct request *req)
-{
-       struct scsi_cmnd *cmd = req->special;
-
-       blk_unprep_request(req);
-       req->special = NULL;
-
-       scsi_put_command(cmd);
-       put_device(&cmd->device->sdev_gendev);
-}
-
 /**
  * __scsi_queue_insert - private queue insertion
  * @cmd: The SCSI command being requeued
@@ -503,16 +480,10 @@ static void scsi_requeue_command(struct request_queue *q, struct scsi_cmnd *cmd)
        struct request *req = cmd->request;
        unsigned long flags;
 
-       /*
-        * We need to hold a reference on the device to avoid the queue being
-        * killed after the unlock and before scsi_run_queue is invoked which
-        * may happen because scsi_unprep_request() puts the command which
-        * releases its reference on the device.
-        */
-       get_device(&sdev->sdev_gendev);
-
        spin_lock_irqsave(q->queue_lock, flags);
-       scsi_unprep_request(req);
+       blk_unprep_request(req);
+       req->special = NULL;
+       scsi_put_command(cmd);
        blk_requeue_request(q, req);
        spin_unlock_irqrestore(q->queue_lock, flags);