Commit 75c668cd authored by Pavel Begunkov's avatar Pavel Begunkov Committed by Jens Axboe
Browse files

io_uring: treat NONBLOCK and RWF_NOWAIT similarly 



Make decision making of whether we need to retry read/write similar for
O_NONBLOCK and RWF_NOWAIT. Set REQ_F_NOWAIT when either is specified and
use it for all relevant checks. Also fix resubmitting NOWAIT requests
via io_rw_reissue().

Signed-off-by: default avatarPavel Begunkov <asml.silence@gmail.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent b23df91b

fs/io_uring.c

+16 −14
Original line number Diff line number Diff line
@@ -2734,7 +2734,9 @@ static bool io_rw_reissue(struct io_kiocb *req, long res) 
	if (res != -EAGAIN && res != -EOPNOTSUPP)

		return false;

	mode = file_inode(req->file)->i_mode;

	if ((!S_ISBLK(mode) && !S_ISREG(mode)) || io_wq_current_is_worker())

	if (!S_ISBLK(mode) && !S_ISREG(mode))

		return false;

	if ((req->flags & REQ_F_NOWAIT) || io_wq_current_is_worker())

		return false;



	lockdep_assert_held(&req->ctx->uring_lock);
@@ -2907,16 +2909,17 @@ static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe) 
{

	struct io_ring_ctx *ctx = req->ctx;

	struct kiocb *kiocb = &req->rw.kiocb;

	struct file *file = req->file;

	unsigned ioprio;

	int ret;



	if (S_ISREG(file_inode(req->file)->i_mode))

	if (S_ISREG(file_inode(file)->i_mode))

		req->flags |= REQ_F_ISREG;



	kiocb->ki_pos = READ_ONCE(sqe->off);

	if (kiocb->ki_pos == -1 && !(req->file->f_mode & FMODE_STREAM)) {

	if (kiocb->ki_pos == -1 && !(file->f_mode & FMODE_STREAM)) {

		req->flags |= REQ_F_CUR_POS;

		kiocb->ki_pos = req->file->f_pos;

		kiocb->ki_pos = file->f_pos;

	}

	kiocb->ki_hint = ki_hint_validate(file_write_hint(kiocb->ki_filp));

	kiocb->ki_flags = iocb_flags(kiocb->ki_filp);
@@ -2924,6 +2927,10 @@ static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe) 
	if (unlikely(ret))

		return ret;



	/* don't allow async punt for O_NONBLOCK or RWF_NOWAIT */

	if ((kiocb->ki_flags & IOCB_NOWAIT) || (file->f_flags & O_NONBLOCK))

		req->flags |= REQ_F_NOWAIT;



	ioprio = READ_ONCE(sqe->ioprio);

	if (ioprio) {

		ret = ioprio_check_cap(ioprio);
@@ -2934,10 +2941,6 @@ static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe) 
	} else

		kiocb->ki_ioprio = get_current_ioprio();



	/* don't allow async punt if RWF_NOWAIT was requested */

	if (kiocb->ki_flags & IOCB_NOWAIT)

		req->flags |= REQ_F_NOWAIT;



	if (ctx->flags & IORING_SETUP_IOPOLL) {

		if (!(kiocb->ki_flags & IOCB_DIRECT) ||

		    !kiocb->ki_filp->f_op->iopoll)
@@ -3546,15 +3549,14 @@ static int io_read(struct io_kiocb *req, bool force_nonblock, 
		/* IOPOLL retry should happen for io-wq threads */

		if (!force_nonblock && !(req->ctx->flags & IORING_SETUP_IOPOLL))

			goto done;

		/* no retry on NONBLOCK marked file */

		if (req->file->f_flags & O_NONBLOCK)

		/* no retry on NONBLOCK nor RWF_NOWAIT */

		if (req->flags & REQ_F_NOWAIT)

			goto done;

		/* some cases will consume bytes even on error returns */

		iov_iter_revert(iter, io_size - iov_iter_count(iter));

		ret = 0;

	} else if (ret <= 0 || ret == io_size || !force_nonblock ||

		   (req->file->f_flags & O_NONBLOCK) ||

		   !(req->flags & REQ_F_ISREG)) {

		   (req->flags & REQ_F_NOWAIT) || !(req->flags & REQ_F_ISREG)) {

		/* read all, failed, already did sync or don't want to retry */

		goto done;

	}
@@ -3675,8 +3677,8 @@ static int io_write(struct io_kiocb *req, bool force_nonblock, 
	 */

	if (ret2 == -EOPNOTSUPP && (kiocb->ki_flags & IOCB_NOWAIT))

		ret2 = -EAGAIN;

	/* no retry on NONBLOCK marked file */

	if (ret2 == -EAGAIN && (req->file->f_flags & O_NONBLOCK))

	/* no retry on NONBLOCK nor RWF_NOWAIT */

	if (ret2 == -EAGAIN && (req->flags & REQ_F_NOWAIT))

		goto done;

	if (!force_nonblock || ret2 != -EAGAIN) {

		/* IOPOLL retry should happen for io-wq threads */