src/patches/suse-2.6.27.31/patches.fixes/block-fix-blk_start_queueing

   1 Subject: block: Fix blk_start_queueing() to not kick a stopped queue
   2 From: Elias Oltmanns <eo@nebensachen.de>
   3 Date: Thu Oct 9 08:56:20 2008 +0200:
   4 Git: 336c3d8ce771608815b65bcfa27a17a83b297328
   5 References: bnc#464155
   6
   7 blk_start_queueing() should act like the generic queue unplugging
   8 and kicking and ignore a stopped queue. Such a queue may not be
   9 run until after a call to blk_start_queue().
  10
  11 Signed-off-by: Elias Oltmanns <eo@nebensachen.de>
  12 Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
  13 Signed-off-by: Hannes Reinecke <hare@suse.de>
  14
  15 ---
  16  block/blk-core.c |    6 ++++--
  17  1 file changed, 4 insertions(+), 2 deletions(-)
  18
  19 --- a/block/blk-core.c
  20 +++ b/block/blk-core.c
  21 @@ -905,9 +905,11 @@ EXPORT_SYMBOL(blk_get_request);
  22   */
  23  void blk_start_queueing(struct request_queue *q)
  24  {
  25 -       if (!blk_queue_plugged(q))
  26 +       if (!blk_queue_plugged(q)) {
  27 +               if (unlikely(blk_queue_stopped(q)))
  28 +                       return;
  29                 q->request_fn(q);
  30 -       else
  31 +       } else
  32                 __generic_unplug_device(q);
  33  }
  34  EXPORT_SYMBOL(blk_start_queueing);