From: Pavel Begunkov <asml.silence@xxxxxxxxx>
[ Upstream commit b7ddce3cbf010edbfac6c6d8cc708560a7bcd7a4 ]
While trying to cancel requests with ->files, it also should look for
requests in ->defer_list, otherwise it might end up hanging a thread.
Cancel all requests in ->defer_list up to the last request there with
matching ->files, that's needed to follow drain ordering semantics.
Signed-off-by: Pavel Begunkov <asml.silence@xxxxxxxxx>
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/io_uring.c | 26 ++++++++++++++++++++++++++
1 file changed, 26 insertions(+)
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 38f3ec15ba3b1..5f627194d0920 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -7675,12 +7675,38 @@ static void io_attempt_cancel(struct io_ring_ctx *ctx, struct io_kiocb *req)
io_timeout_remove_link(ctx, req);
}
+static void io_cancel_defer_files(struct io_ring_ctx *ctx,
+ struct files_struct *files)
+{
+ struct io_kiocb *req = NULL;
+ LIST_HEAD(list);
+
+ spin_lock_irq(&ctx->completion_lock);
+ list_for_each_entry_reverse(req, &ctx->defer_list, list) {
+ if ((req->flags & REQ_F_WORK_INITIALIZED)
+ && req->work.files == files) {
+ list_cut_position(&list, &ctx->defer_list, &req->list);
+ break;
+ }
+ }
+ spin_unlock_irq(&ctx->completion_lock);
+
+ while (!list_empty(&list)) {
+ req = list_first_entry(&list, struct io_kiocb, list);
+ list_del_init(&req->list);
+ req_set_fail_links(req);
+ io_cqring_add_event(req, -ECANCELED);
+ io_double_put_req(req);
+ }
+}
+
static void io_uring_cancel_files(struct io_ring_ctx *ctx,
struct files_struct *files)
{
if (list_empty_careful(&ctx->inflight_list))
return;
+ io_cancel_defer_files(ctx, files);
/* cancel all at once, should be faster than doing it one by one*/
io_wq_cancel_cb(ctx->io_wq, io_wq_files_match, files, true);
--
2.25.1
