From 62755e35dfb2b113c52b81cd96d01c20971c8e02 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Mon, 28 Oct 2019 21:49:21 -0600 Subject: io_uring: support for generic async request cancel This adds support for IORING_OP_ASYNC_CANCEL, which will attempt to cancel requests that have been punted to async context and are now in-flight. This works for regular read/write requests to files, as long as they haven't been started yet. For socket based IO (or things like accept4(2)), we can cancel work that is already running as well. To cancel a request, the sqe must have ->addr set to the user_data of the request it wishes to cancel. If the request is cancelled successfully, the original request is completed with -ECANCELED and the cancel request is completed with a result of 0. If the request was already running, the original may or may not complete in error. The cancel request will complete with -EALREADY for that case. And finally, if the request to cancel wasn't found, the cancel request is completed with -ENOENT. Signed-off-by: Jens Axboe --- fs/io-wq.h | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'fs/io-wq.h') diff --git a/fs/io-wq.h b/fs/io-wq.h index e93f764b1fa4..3de192dc73fc 100644 --- a/fs/io-wq.h +++ b/fs/io-wq.h @@ -43,6 +43,11 @@ void io_wq_flush(struct io_wq *wq); void io_wq_cancel_all(struct io_wq *wq); enum io_wq_cancel io_wq_cancel_work(struct io_wq *wq, struct io_wq_work *cwork); +typedef bool (work_cancel_fn)(struct io_wq_work *, void *); + +enum io_wq_cancel io_wq_cancel_cb(struct io_wq *wq, work_cancel_fn *cancel, + void *data); + #if defined(CONFIG_IO_WQ) extern void io_wq_worker_sleeping(struct task_struct *); extern void io_wq_worker_running(struct task_struct *); -- cgit v1.2.3-70-g09d2