Commit 2fcb88bd authored by Caleb Sander Mateos's avatar Caleb Sander Mateos Committed by Jens Axboe
Browse files

ublk: factor out ublk_start_io() helper 



In preparation for calling it from outside ublk_dispatch_req(), factor
out the code responsible for setting up an incoming ublk I/O request.

Signed-off-by: default avatarCaleb Sander Mateos <csander@purestorage.com>
Reviewed-by: default avatarMing Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20250430225234.2676781-7-csander@purestorage.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 55127069

drivers/block/ublk_drv.c

+31 −23
Original line number Diff line number Diff line
@@ -1152,13 +1152,41 @@ static inline void __ublk_abort_rq(struct ublk_queue *ubq, 
		blk_mq_end_request(rq, BLK_STS_IOERR);

}



static bool ublk_start_io(const struct ublk_queue *ubq, struct request *req,

			  struct ublk_io *io)

{

	unsigned mapped_bytes = ublk_map_io(ubq, req, io);



	/* partially mapped, update io descriptor */

	if (unlikely(mapped_bytes != blk_rq_bytes(req))) {

		/*

		 * Nothing mapped, retry until we succeed.

		 *

		 * We may never succeed in mapping any bytes here because

		 * of OOM. TODO: reserve one buffer with single page pinned

		 * for providing forward progress guarantee.

		 */

		if (unlikely(!mapped_bytes)) {

			blk_mq_requeue_request(req, false);

			blk_mq_delay_kick_requeue_list(req->q,

					UBLK_REQUEUE_DELAY_MS);

			return false;

		}



		ublk_get_iod(ubq, req->tag)->nr_sectors =

			mapped_bytes >> 9;

	}



	ublk_init_req_ref(ubq, req);

	return true;

}



static void ublk_dispatch_req(struct ublk_queue *ubq,

			      struct request *req,

			      unsigned int issue_flags)

{

	int tag = req->tag;

	struct ublk_io *io = &ubq->ios[tag];

	unsigned int mapped_bytes;



	pr_devel("%s: complete: qid %d tag %d io_flags %x addr %llx\n",

			__func__, ubq->q_id, req->tag, io->flags,
@@ -1205,29 +1233,9 @@ static void ublk_dispatch_req(struct ublk_queue *ubq, 
				ublk_get_iod(ubq, req->tag)->addr);

	}



	mapped_bytes = ublk_map_io(ubq, req, io);



	/* partially mapped, update io descriptor */

	if (unlikely(mapped_bytes != blk_rq_bytes(req))) {

		/*

		 * Nothing mapped, retry until we succeed.

		 *

		 * We may never succeed in mapping any bytes here because

		 * of OOM. TODO: reserve one buffer with single page pinned

		 * for providing forward progress guarantee.

		 */

		if (unlikely(!mapped_bytes)) {

			blk_mq_requeue_request(req, false);

			blk_mq_delay_kick_requeue_list(req->q,

					UBLK_REQUEUE_DELAY_MS);

	if (!ublk_start_io(ubq, req, io))

		return;

		}



		ublk_get_iod(ubq, req->tag)->nr_sectors =

			mapped_bytes >> 9;

	}



	ublk_init_req_ref(ubq, req);

	ublk_complete_io_cmd(io, UBLK_IO_RES_OK, issue_flags);

}