Commit 0cb39afd authored by Uday Shankar's avatar Uday Shankar Committed by Jens Axboe
Browse files

ublk: factor out ublk_commit_and_fetch 



Move the logic for the UBLK_IO_COMMIT_AND_FETCH_REQ opcode into its own
function. This also allows us to mark ublk_queue pointers as const for
that operation, which can help prevent data races since we may allow
concurrent operation on one ublk_queue in the future. Also open code
ublk_commit_completion in ublk_commit_and_fetch to reduce the number of
parameters/avoid a redundant lookup.

[Restore __ublk_ch_uring_cmd() req variable used in commit d6aa0c17
("ublk: call ublk_dispatch_req() for handling UBLK_U_IO_NEED_GET_DATA")]

Suggested-by: default avatarMing Lei <ming.lei@redhat.com>
Signed-off-by: default avatarUday Shankar <ushankar@purestorage.com>
Reviewed-by: default avatarCaleb Sander Mateos <csander@purestorage.com>
Reviewed-by: default avatarMing Lei <ming.lei@redhat.com>
Signed-off-by: default avatarCaleb Sander Mateos <csander@purestorage.com>
Link: https://lore.kernel.org/r/20250430225234.2676781-2-csander@purestorage.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 9712c57e

drivers/block/ublk_drv.c

+43 −47
Original line number Diff line number Diff line
@@ -1589,30 +1589,6 @@ static int ublk_ch_mmap(struct file *filp, struct vm_area_struct *vma) 
	return remap_pfn_range(vma, vma->vm_start, pfn, sz, vma->vm_page_prot);

}



static void ublk_commit_completion(struct ublk_device *ub,

		const struct ublksrv_io_cmd *ub_cmd)

{

	u32 qid = ub_cmd->q_id, tag = ub_cmd->tag;

	struct ublk_queue *ubq = ublk_get_queue(ub, qid);

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

	struct request *req;



	/* now this cmd slot is owned by nbd driver */

	io->flags &= ~UBLK_IO_FLAG_OWNED_BY_SRV;

	io->res = ub_cmd->result;



	/* find the io request and complete */

	req = blk_mq_tag_to_rq(ub->tag_set.tags[qid], tag);

	if (WARN_ON_ONCE(unlikely(!req)))

		return;



	if (req_op(req) == REQ_OP_ZONE_APPEND)

		req->__sector = ub_cmd->zone_append_lba;



	if (likely(!blk_should_fake_timeout(req->q)))

		ublk_put_req_ref(ubq, req);

}



static void __ublk_fail_req(struct ublk_queue *ubq, struct ublk_io *io,

		struct request *req)

{
@@ -2021,6 +1997,47 @@ static int ublk_fetch(struct io_uring_cmd *cmd, struct ublk_queue *ubq, 
	return ret;

}



static int ublk_commit_and_fetch(const struct ublk_queue *ubq,

				 struct ublk_io *io, struct io_uring_cmd *cmd,

				 const struct ublksrv_io_cmd *ub_cmd)

{

	struct blk_mq_tags *tags = ubq->dev->tag_set.tags[ub_cmd->q_id];

	struct request *req = blk_mq_tag_to_rq(tags, ub_cmd->tag);



	if (!(io->flags & UBLK_IO_FLAG_OWNED_BY_SRV))

		return -EINVAL;



	if (ublk_need_map_io(ubq)) {

		/*

		 * COMMIT_AND_FETCH_REQ has to provide IO buffer if

		 * NEED GET DATA is not enabled or it is Read IO.

		 */

		if (!ub_cmd->addr && (!ublk_need_get_data(ubq) ||

					req_op(req) == REQ_OP_READ))

			return -EINVAL;

	} else if (req_op(req) != REQ_OP_ZONE_APPEND && ub_cmd->addr) {

		/*

		 * User copy requires addr to be unset when command is

		 * not zone append

		 */

		return -EINVAL;

	}



	ublk_fill_io_cmd(io, cmd, ub_cmd->addr);



	/* now this cmd slot is owned by ublk driver */

	io->flags &= ~UBLK_IO_FLAG_OWNED_BY_SRV;

	io->res = ub_cmd->result;



	if (req_op(req) == REQ_OP_ZONE_APPEND)

		req->__sector = ub_cmd->zone_append_lba;



	if (likely(!blk_should_fake_timeout(req->q)))

		ublk_put_req_ref(ubq, req);



	return 0;

}



static int __ublk_ch_uring_cmd(struct io_uring_cmd *cmd,

			       unsigned int issue_flags,

			       const struct ublksrv_io_cmd *ub_cmd)
@@ -2079,30 +2096,9 @@ static int __ublk_ch_uring_cmd(struct io_uring_cmd *cmd, 
			goto out;

		break;

	case UBLK_IO_COMMIT_AND_FETCH_REQ:

		req = blk_mq_tag_to_rq(ub->tag_set.tags[ub_cmd->q_id], tag);



		if (!(io->flags & UBLK_IO_FLAG_OWNED_BY_SRV))

			goto out;



		if (ublk_need_map_io(ubq)) {

			/*

			 * COMMIT_AND_FETCH_REQ has to provide IO buffer if

			 * NEED GET DATA is not enabled or it is Read IO.

			 */

			if (!ub_cmd->addr && (!ublk_need_get_data(ubq) ||

						req_op(req) == REQ_OP_READ))

				goto out;

		} else if (req_op(req) != REQ_OP_ZONE_APPEND && ub_cmd->addr) {

			/*

			 * User copy requires addr to be unset when command is

			 * not zone append

			 */

			ret = -EINVAL;

		ret = ublk_commit_and_fetch(ubq, io, cmd, ub_cmd);

		if (ret)

			goto out;

		}



		ublk_fill_io_cmd(io, cmd, ub_cmd->addr);

		ublk_commit_completion(ub, ub_cmd);

		break;

	case UBLK_IO_NEED_GET_DATA:

		if (!(io->flags & UBLK_IO_FLAG_OWNED_BY_SRV))