block: disable discard request merge temporarily

The SCSI discard request merge never worked, and looks no solution
for in future, let's disable it temporarily.

Signed-off-by: Shaohua Li <shli@fusionio.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Shaohua Li 2012-08-09 15:20:23 +02:00 committed by Jens Axboe
parent 389d7b26d9
commit 276f0f5d15

View File

@ -601,7 +601,7 @@ static inline void blk_clear_rl_full(struct request_list *rl, bool sync)
* it already be started by driver.
*/
#define RQ_NOMERGE_FLAGS \
(REQ_NOMERGE | REQ_STARTED | REQ_SOFTBARRIER | REQ_FLUSH | REQ_FUA)
(REQ_NOMERGE | REQ_STARTED | REQ_SOFTBARRIER | REQ_FLUSH | REQ_FUA | REQ_DISCARD)
#define rq_mergeable(rq) \
(!((rq)->cmd_flags & RQ_NOMERGE_FLAGS) && \
(((rq)->cmd_flags & REQ_DISCARD) || \