blk_barrier_rq    208 block/blk-barrier.c 	const int is_barrier = blk_fs_request(rq) && blk_barrier_rq(rq);
blk_barrier_rq    691 block/elevator.c 		if (blk_barrier_rq(rq))
blk_barrier_rq    579 include/linux/blkdev.h #define blk_empty_barrier(rq)	(blk_barrier_rq(rq) && blk_fs_request(rq) && !(rq)->hard_nr_sectors)