Commit b711d4ea authored by Jens Axboe's avatar Jens Axboe
Browse files

io_uring: find and cancel head link async work on files exit 



Commit f254ac04 ("io_uring: enable lookup of links holding inflight files")
only handled 2 out of the three head link cases we have, we also need to
lookup and cancel work that is blocked in io-wq if that work has a link
that's holding a reference to the files structure.

Put the "cancel head links that hold this request pending" logic into
io_attempt_cancel(), which will to through the motions of finding and
canceling head links that hold the current inflight files stable request
pending.

Cc: stable@vger.kernel.org
Reported-by: default avatarPavel Begunkov <asml.silence@gmail.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 9123e3a7

fs/io_uring.c

+29 −4
Original line number Diff line number Diff line
@@ -8063,6 +8063,33 @@ static bool io_timeout_remove_link(struct io_ring_ctx *ctx, 
	return found;

}



static bool io_cancel_link_cb(struct io_wq_work *work, void *data)

{

	return io_match_link(container_of(work, struct io_kiocb, work), data);

}



static void io_attempt_cancel(struct io_ring_ctx *ctx, struct io_kiocb *req)

{

	enum io_wq_cancel cret;



	/* cancel this particular work, if it's running */

	cret = io_wq_cancel_work(ctx->io_wq, &req->work);

	if (cret != IO_WQ_CANCEL_NOTFOUND)

		return;



	/* find links that hold this pending, cancel those */

	cret = io_wq_cancel_cb(ctx->io_wq, io_cancel_link_cb, req, true);

	if (cret != IO_WQ_CANCEL_NOTFOUND)

		return;



	/* if we have a poll link holding this pending, cancel that */

	if (io_poll_remove_link(ctx, req))

		return;



	/* final option, timeout link is holding this req pending */

	io_timeout_remove_link(ctx, req);

}



static void io_uring_cancel_files(struct io_ring_ctx *ctx,

				  struct files_struct *files)

{
@@ -8116,10 +8143,8 @@ static void io_uring_cancel_files(struct io_ring_ctx *ctx, 
				continue;

			}

		} else {

			io_wq_cancel_work(ctx->io_wq, &cancel_req->work);

			/* could be a link, check and remove if it is */

			if (!io_poll_remove_link(ctx, cancel_req))

				io_timeout_remove_link(ctx, cancel_req);

			/* cancel this request, or head link requests */

			io_attempt_cancel(ctx, cancel_req);

			io_put_req(cancel_req);

		}

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