Commit 8cb01fac authored by Pavel Begunkov's avatar Pavel Begunkov Committed by Jens Axboe
Browse files

io_uring: deduplicate cancellation code 



IORING_OP_ASYNC_CANCEL and IORING_OP_LINK_TIMEOUT have enough of
overlap, so extract a helper for request cancellation and use in both.
Also, removes some amount of ugliness because of success_ret.

Signed-off-by: default avatarPavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/900122b588e65b637e71bfec80a260726c6a54d6.1628981736.git.asml.silence@gmail.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent a8576af9

fs/io_uring.c

+18 −28
Original line number Diff line number Diff line
@@ -5792,32 +5792,24 @@ static int io_async_cancel_one(struct io_uring_task *tctx, u64 user_data, 
	return ret;

}



static void io_async_find_and_cancel(struct io_ring_ctx *ctx,

				     struct io_kiocb *req, __u64 sqe_addr,

				     int success_ret)

static int io_try_cancel_userdata(struct io_kiocb *req, u64 sqe_addr)

	__acquires(&req->ctx->completion_lock)

{

	struct io_ring_ctx *ctx = req->ctx;

	int ret;



	WARN_ON_ONCE(req->task != current);



	ret = io_async_cancel_one(req->task->io_uring, sqe_addr, ctx);

	spin_lock(&ctx->completion_lock);

	if (ret != -ENOENT)

		goto done;

		return ret;

	spin_lock_irq(&ctx->timeout_lock);

	ret = io_timeout_cancel(ctx, sqe_addr);

	spin_unlock_irq(&ctx->timeout_lock);

	if (ret != -ENOENT)

		goto done;

	ret = io_poll_cancel(ctx, sqe_addr, false);

done:

	if (!ret)

		ret = success_ret;

	io_cqring_fill_event(ctx, req->user_data, ret, 0);

	io_commit_cqring(ctx);

	spin_unlock(&ctx->completion_lock);

	io_cqring_ev_posted(ctx);



	if (ret < 0)

		req_set_fail(req);

		return ret;

	return io_poll_cancel(ctx, sqe_addr, false);

}



static int io_async_cancel_prep(struct io_kiocb *req,
@@ -5841,17 +5833,7 @@ static int io_async_cancel(struct io_kiocb *req, unsigned int issue_flags) 
	struct io_tctx_node *node;

	int ret;



	/* tasks should wait for their io-wq threads, so safe w/o sync */

	ret = io_async_cancel_one(req->task->io_uring, sqe_addr, ctx);

	spin_lock(&ctx->completion_lock);

	if (ret != -ENOENT)

		goto done;

	spin_lock_irq(&ctx->timeout_lock);

	ret = io_timeout_cancel(ctx, sqe_addr);

	spin_unlock_irq(&ctx->timeout_lock);

	if (ret != -ENOENT)

		goto done;

	ret = io_poll_cancel(ctx, sqe_addr, false);

	ret = io_try_cancel_userdata(req, sqe_addr);

	if (ret != -ENOENT)

		goto done;

	spin_unlock(&ctx->completion_lock);
@@ -6418,9 +6400,17 @@ static void io_req_task_link_timeout(struct io_kiocb *req) 
{

	struct io_kiocb *prev = req->timeout.prev;

	struct io_ring_ctx *ctx = req->ctx;

	int ret;



	if (prev) {

		io_async_find_and_cancel(ctx, req, prev->user_data, -ETIME);

		ret = io_try_cancel_userdata(req, prev->user_data);

		if (!ret)

			ret = -ETIME;

		io_cqring_fill_event(ctx, req->user_data, ret, 0);

		io_commit_cqring(ctx);

		spin_unlock(&ctx->completion_lock);

		io_cqring_ev_posted(ctx);



		io_put_req(prev);

		io_put_req(req);

	} else {