[PATCH] [ [trivial]] block: update comments about bd_start_claiming().

[majianpeng <majianpeng@gmail.com>]

Because the bd_finish_claiming()/bd_abort_claiming() removed,so update
the comments. And fix a typo.

Signed-off-by: Jianpeng Ma <majianpeng@gmail.com>
---
 fs/block_dev.c |    8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/fs/block_dev.c b/fs/block_dev.c
index 1a1e5e3..ceda8b9 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -787,13 +787,11 @@ retry:
  * @holder: holder trying to claim @bdev
  *
  * @bdev is about to be opened exclusively.  Check @bdev can be opened
- * exclusively and mark that an exclusive open is in progress.  Each
- * successful call to this function must be matched with a call to
- * either bd_finish_claiming() or bd_abort_claiming() (which do not
- * fail).
+ * exclusively and mark that an exclusive open is in progress.
+ * The release rolled into blkdev_put().
  *
  * This function is used to gain exclusive access to the block device
- * without actually causing other exclusive open attempts to fail. It
+ * without actually causing other non-exclusive open attempts to fail. It
  * should be used when the open sequence itself requires exclusive
  * access but may subsequently fail.
  *
-- 
1.7.9.5