block: add dma_map_bvec helper



Provide a nice little shortcut for mapping a single bvec.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>

parent 9d9de535

include/linux/blkdev.h

+4 −0

Original line number	Diff line number	Diff line
		@@ -644,6 +644,10 @@ static inline bool blk_account_rq(struct request *rq)
		#define rq_dma_dir(rq) \
		(op_is_write(req_op(rq)) ? DMA_TO_DEVICE : DMA_FROM_DEVICE)

		#define dma_map_bvec(dev, bv, dir, attrs) \
		dma_map_page_attrs(dev, (bv)->bv_page, (bv)->bv_offset, (bv)->bv_len, \
		(dir), (attrs))

		static inline bool queue_is_mq(struct request_queue *q)
		{
		return q->mq_ops;