MD(especially raid1 and raid10) is a bit difficult to support multipage bvec, so introduce this flag for not enabling multipage bvec, then MD can still accept singlepage bvec only, and once direct access to bvec table in MD are cleanuped, the flag can be removed. Signed-off-by: Ming Lei <tom.leiming@xxxxxxxxx> --- include/linux/blkdev.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index 83695641bd5e..0c02d9778965 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -600,6 +600,7 @@ struct request_queue { #define QUEUE_FLAG_FLUSH_NQ 25 /* flush not queueuable */ #define QUEUE_FLAG_DAX 26 /* device supports DAX */ #define QUEUE_FLAG_STATS 27 /* track rq completion times */ +#define QUEUE_FLAG_NO_MP 28 /* multipage bvecs isn't ready */ #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \ (1 << QUEUE_FLAG_STACKABLE) | \ @@ -690,6 +691,7 @@ static inline void queue_flag_clear(unsigned int flag, struct request_queue *q) #define blk_queue_secure_erase(q) \ (test_bit(QUEUE_FLAG_SECERASE, &(q)->queue_flags)) #define blk_queue_dax(q) test_bit(QUEUE_FLAG_DAX, &(q)->queue_flags) +#define blk_queue_no_mp(q) test_bit(QUEUE_FLAG_NO_MP, &(q)->queue_flags) #define blk_noretry_request(rq) \ ((rq)->cmd_flags & (REQ_FAILFAST_DEV|REQ_FAILFAST_TRANSPORT| \ -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe linux-block" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html