Merge branch 'for-2.6.37/barrier' of git://git.kernel.dk/linux-2.6-block

* 'for-2.6.37/barrier' of git://git.kernel.dk/linux-2.6-block: (46 commits)
  xen-blkfront: disable barrier/flush write support
  Added blk-lib.c and blk-barrier.c was renamed to blk-flush.c
  block: remove BLKDEV_IFL_WAIT
  aic7xxx_old: removed unused 'req' variable
  block: remove the BH_Eopnotsupp flag
  block: remove the BLKDEV_IFL_BARRIER flag
  block: remove the WRITE_BARRIER flag
  swap: do not send discards as barriers
  fat: do not send discards as barriers
  ext4: do not send discards as barriers
  jbd2: replace barriers with explicit flush / FUA usage
  jbd2: Modify ASYNC_COMMIT code to not rely on queue draining on barrier
  jbd: replace barriers with explicit flush / FUA usage
  nilfs2: replace barriers with explicit flush / FUA usage
  reiserfs: replace barriers with explicit flush / FUA usage
  gfs2: replace barriers with explicit flush / FUA usage
  btrfs: replace barriers with explicit flush / FUA usage
  xfs: replace barriers with explicit flush / FUA usage
  block: pass gfp_mask and flags to sb_issue_discard
  dm: convey that all flushes are processed as empty
  ...

1 files changed, 3 insertions, 3 deletions

diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c
index f30f6e8d594e..53cf79d8bcbc 100644
--- a/drivers/md/dm-snap.c
+++ b/drivers/md/dm-snap.c
@@ -1585,7 +1585,7 @@ static int snapshot_map(struct dm_target *ti, struct bio *bio,
         chunk_t chunk;
         struct dm_snap_pending_exception *pe = NULL;
 
-        if (unlikely(bio_empty_barrier(bio))) {
+        if (bio->bi_rw & REQ_FLUSH) {
                 bio->bi_bdev = s->cow->bdev;
                 return DM_MAPIO_REMAPPED;
         }
@@ -1689,7 +1689,7 @@ static int snapshot_merge_map(struct dm_target *ti, struct bio *bio,
         int r = DM_MAPIO_REMAPPED;
         chunk_t chunk;
 
-        if (unlikely(bio_empty_barrier(bio))) {
+        if (bio->bi_rw & REQ_FLUSH) {
                 if (!map_context->target_request_nr)
                         bio->bi_bdev = s->origin->bdev;
                 else
@@ -2133,7 +2133,7 @@ static int origin_map(struct dm_target *ti, struct bio *bio,
         struct dm_dev *dev = ti->private;
         bio->bi_bdev = dev->bdev;
 
-        if (unlikely(bio_empty_barrier(bio)))
+        if (bio->bi_rw & REQ_FLUSH)
                 return DM_MAPIO_REMAPPED;
 
         /* Only tell snapshots if this is a write */