Commit ee977363 authored by Caleb Sander Mateos's avatar Caleb Sander Mateos Committed by Jens Axboe
Browse files

ublk: handle UBLK_IO_FETCH_REQ earlier 



Check for UBLK_IO_FETCH_REQ early in __ublk_ch_uring_cmd() and skip the
rest of the checks in this case. This allows removing the checks for
NULL io->task and UBLK_IO_FLAG_OWNED_BY_SRV unset in io->flags, which
are only allowed for FETCH.

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/20250620151008.3976463-5-csander@purestorage.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 5af8b36f

drivers/block/ublk_drv.c

+12 −9
Original line number Diff line number Diff line
@@ -2215,8 +2215,18 @@ static int __ublk_ch_uring_cmd(struct io_uring_cmd *cmd, 
		goto out;



	io = &ubq->ios[tag];

	/* UBLK_IO_FETCH_REQ can be handled on any task, which sets io->task */

	if (unlikely(_IOC_NR(cmd_op) == UBLK_IO_FETCH_REQ)) {

		ret = ublk_fetch(cmd, ubq, io, ub_cmd->addr);

		if (ret)

			goto out;



		ublk_prep_cancel(cmd, issue_flags, ubq, tag);

		return -EIOCBQUEUED;

	}



	task = READ_ONCE(io->task);

	if (task && task != current)

	if (task != current)

		goto out;



	/* there is pending io cmd, something must be wrong */
@@ -2225,9 +2235,7 @@ static int __ublk_ch_uring_cmd(struct io_uring_cmd *cmd, 
		goto out;

	}



	/* only UBLK_IO_FETCH_REQ is allowed if io is not OWNED_BY_SRV */

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

	    _IOC_NR(cmd_op) != UBLK_IO_FETCH_REQ)

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

		goto out;



	/*
@@ -2243,11 +2251,6 @@ static int __ublk_ch_uring_cmd(struct io_uring_cmd *cmd, 
		return ublk_register_io_buf(cmd, ubq, io, ub_cmd->addr, issue_flags);

	case UBLK_IO_UNREGISTER_IO_BUF:

		return ublk_unregister_io_buf(cmd, ubq, ub_cmd->addr, issue_flags);

	case UBLK_IO_FETCH_REQ:

		ret = ublk_fetch(cmd, ubq, io, ub_cmd->addr);

		if (ret)

			goto out;

		break;

	case UBLK_IO_COMMIT_AND_FETCH_REQ:

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

		if (ret)