io_uring: always go async for unsupported open flags

No point in issuing -> return -EAGAIN -> go async, when it can be done upfront.

Signed-off-by: Dylan Yudaken <dylany@meta.com>
Link: https://lore.kernel.org/r/20230127135227.3646353-5-dylany@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/io_uring/openclose.c b/io_uring/openclose.c
index 67178e4bb282d541a69d096241fa7065a4c8a7c6..a1b98c81a52d9c3028a298fdb2d2414dba1f497b 100644 (file)
--- a/io_uring/openclose.c
+++ b/io_uring/openclose.c
@@ -31,6 +31,15 @@ struct io_close {
        u32                             file_slot;
 };
 
+static bool io_openat_force_async(struct io_open *open)
+{
+       /*
+        * Don't bother trying for O_TRUNC, O_CREAT, or O_TMPFILE open,
+        * it'll always -EAGAIN
+        */
+       return open->how.flags & (O_TRUNC | O_CREAT | O_TMPFILE);
+}
+
 static int __io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 {
        struct io_open *open = io_kiocb_to_cmd(req, struct io_open);
@@ -61,6 +70,8 @@ static int __io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe
 
        open->nofile = rlimit(RLIMIT_NOFILE);
        req->flags |= REQ_F_NEED_CLEANUP;
+       if (io_openat_force_async(open))
+               req->flags |= REQ_F_FORCE_ASYNC;
        return 0;
 }
 
@@ -108,12 +119,7 @@ int io_openat2(struct io_kiocb *req, unsigned int issue_flags)
        nonblock_set = op.open_flag & O_NONBLOCK;
        resolve_nonblock = open->how.resolve & RESOLVE_CACHED;
        if (issue_flags & IO_URING_F_NONBLOCK) {
-               /*
-                * Don't bother trying for O_TRUNC, O_CREAT, or O_TMPFILE open,
-                * it'll always -EAGAIN
-                */
-               if (open->how.flags & (O_TRUNC | O_CREAT | O_TMPFILE))
-                       return -EAGAIN;
+               WARN_ON_ONCE(io_openat_force_async(open));
                op.lookup_flags |= LOOKUP_CACHED;
                op.open_flag |= O_NONBLOCK;
        }