Commit 58f99373 authored by Pavel Begunkov's avatar Pavel Begunkov Committed by Jens Axboe
Browse files

io_uring: fix OP_ASYNC_CANCEL across tasks 



IORING_OP_ASYNC_CANCEL tries io-wq cancellation only for current task.
If it fails go over tctx_list and try it out for every single tctx.

Signed-off-by: default avatarPavel Begunkov <asml.silence@gmail.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 521d6a73

fs/io_uring.c

+40 −1
Original line number Diff line number Diff line
@@ -5667,8 +5667,47 @@ static int io_async_cancel_prep(struct io_kiocb *req, 
static int io_async_cancel(struct io_kiocb *req, unsigned int issue_flags)

{

	struct io_ring_ctx *ctx = req->ctx;

	u64 sqe_addr = req->cancel.addr;

	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_irq(&ctx->completion_lock);

	if (ret != -ENOENT)

		goto done;

	ret = io_timeout_cancel(ctx, sqe_addr);

	if (ret != -ENOENT)

		goto done;

	ret = io_poll_cancel(ctx, sqe_addr);

	if (ret != -ENOENT)

		goto done;

	spin_unlock_irq(&ctx->completion_lock);



	/* slow path, try all io-wq's */

	io_ring_submit_lock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));

	ret = -ENOENT;

	list_for_each_entry(node, &ctx->tctx_list, ctx_node) {

		struct io_uring_task *tctx = node->task->io_uring;



	io_async_find_and_cancel(ctx, req, req->cancel.addr, 0);

		if (!tctx || !tctx->io_wq)

			continue;

		ret = io_async_cancel_one(tctx, req->cancel.addr, ctx);

		if (ret != -ENOENT)

			break;

	}

	io_ring_submit_unlock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));



	spin_lock_irq(&ctx->completion_lock);

done:

	io_cqring_fill_event(req, ret);

	io_commit_cqring(ctx);

	spin_unlock_irq(&ctx->completion_lock);

	io_cqring_ev_posted(ctx);



	if (ret < 0)

		req_set_fail_links(req);

	io_put_req(req);

	return 0;

}