Commit c3e6c111 authored by Ming Lei's avatar Ming Lei Committed by Jens Axboe
Browse files

loop: add helper lo_cmd_nr_bvec() 



Add lo_cmd_nr_bvec() and prepare for refactoring lo_rw_aio().

Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarMing Lei <ming.lei@redhat.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 2c6d792d

drivers/block/loop.c

+14 −4
Original line number Diff line number Diff line
@@ -337,6 +337,19 @@ static void lo_rw_aio_complete(struct kiocb *iocb, long ret) 
	lo_rw_aio_do_completion(cmd);

}



static inline unsigned lo_cmd_nr_bvec(struct loop_cmd *cmd)

{

	struct request *rq = blk_mq_rq_from_pdu(cmd);

	struct req_iterator rq_iter;

	struct bio_vec tmp;

	int nr_bvec = 0;



	rq_for_each_bvec(tmp, rq, rq_iter)

		nr_bvec++;



	return nr_bvec;

}



static int lo_rw_aio(struct loop_device *lo, struct loop_cmd *cmd,

		     loff_t pos, int rw)

{
@@ -348,12 +361,9 @@ static int lo_rw_aio(struct loop_device *lo, struct loop_cmd *cmd, 
	struct file *file = lo->lo_backing_file;

	struct bio_vec tmp;

	unsigned int offset;

	int nr_bvec = 0;

	int nr_bvec = lo_cmd_nr_bvec(cmd);

	int ret;



	rq_for_each_bvec(tmp, rq, rq_iter)

		nr_bvec++;



	if (rq->bio != rq->biotail) {



		bvec = kmalloc_array(nr_bvec, sizeof(struct bio_vec),