io_uring/cmd: fix tw <-> issue_flags conversion

!IO_URING_F_UNLOCKED does not translate to availability of the deferred
completion infra, IO_URING_F_COMPLETE_DEFER does, that what we should
pass and look for to use io_req_complete_defer() and other variants.

Luckily, it's not a real problem as two wrongs actually made it right,
at least as far as io_uring_cmd_work() goes.

Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/aef76d34fe9410df8ecc42a14544fd76cd9d8b9e.1710799188.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/io_uring/uring_cmd.c b/io_uring/uring_cmd.c
index 7c1c58c5837eeba1d11b4921d9f97c6b47c9673e..759f919b14a9905852c045a8fd709123ea4dec8a 100644 (file)
--- a/io_uring/uring_cmd.c
+++ b/io_uring/uring_cmd.c
@@ -36,7 +36,8 @@ bool io_uring_try_cancel_uring_cmd(struct io_ring_ctx *ctx,
                        /* ->sqe isn't available if no async data */
                        if (!req_has_async_data(req))
                                cmd->sqe = NULL;
-                       file->f_op->uring_cmd(cmd, IO_URING_F_CANCEL);
+                       file->f_op->uring_cmd(cmd, IO_URING_F_CANCEL |
+                                                  IO_URING_F_COMPLETE_DEFER);
                        ret = true;
                }
        }
@@ -86,7 +87,11 @@ EXPORT_SYMBOL_GPL(io_uring_cmd_mark_cancelable);
 static void io_uring_cmd_work(struct io_kiocb *req, struct io_tw_state *ts)
 {
        struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req, struct io_uring_cmd);
-       unsigned issue_flags = ts->locked ? 0 : IO_URING_F_UNLOCKED;
+       unsigned issue_flags = IO_URING_F_UNLOCKED;
+
+       /* locked task_work executor checks the deffered list completion */
+       if (ts->locked)
+               issue_flags = IO_URING_F_COMPLETE_DEFER;
 
        ioucmd->task_work_cb(ioucmd, issue_flags);
 }
@@ -130,7 +135,9 @@ void io_uring_cmd_done(struct io_uring_cmd *ioucmd, ssize_t ret, ssize_t res2,
        if (req->ctx->flags & IORING_SETUP_IOPOLL) {
                /* order with io_iopoll_req_issued() checking ->iopoll_complete */
                smp_store_release(&req->iopoll_completed, 1);
-       } else if (!(issue_flags & IO_URING_F_UNLOCKED)) {
+       } else if (issue_flags & IO_URING_F_COMPLETE_DEFER) {
+               if (WARN_ON_ONCE(issue_flags & IO_URING_F_UNLOCKED))
+                       return;
                io_req_complete_defer(req);
        } else {
                req->io_task_work.func = io_req_task_complete;