io_uring: add io_link_sqe() helper

Add io_link_sqe() helper, so that io_submit_sqe() can become more
readable.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
Link: https://lore.kernel.org/r/20241025122247.3709133-2-ming.lei@redhat.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index 042a65d38d0c50b3eda2f6be9d43b13d1707f581..24495ddfe4832f9ed310d6385dc02f592da41c25 100644 (file)
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -2130,19 +2130,11 @@ static __cold int io_submit_fail_init(const struct io_uring_sqe *sqe,
        return 0;
 }
 
-static inline int io_submit_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req,
-                        const struct io_uring_sqe *sqe)
-       __must_hold(&ctx->uring_lock)
+/*
+ * Return NULL if nothing to be queued, otherwise return request for queueing */
+static struct io_kiocb *io_link_sqe(struct io_submit_link *link,
+                                   struct io_kiocb *req)
 {
-       struct io_submit_link *link = &ctx->submit_state.link;
-       int ret;
-
-       ret = io_init_req(ctx, req, sqe);
-       if (unlikely(ret))
-               return io_submit_fail_init(sqe, req, ret);
-
-       trace_io_uring_submit_req(req);
-
        /*
         * If we already have a head request, queue this one for async
         * submittal once the head completes. If we don't have a head but
@@ -2156,7 +2148,7 @@ static inline int io_submit_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req,
                link->last = req;
 
                if (req->flags & IO_REQ_LINK_FLAGS)
-                       return 0;
+                       return NULL;
                /* last request of the link, flush it */
                req = link->head;
                link->head = NULL;
@@ -2172,9 +2164,30 @@ static inline int io_submit_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req,
 fallback:
                        io_queue_sqe_fallback(req);
                }
-               return 0;
+               return NULL;
        }
+       return req;
+}
+
+static inline int io_submit_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req,
+                        const struct io_uring_sqe *sqe)
+       __must_hold(&ctx->uring_lock)
+{
+       struct io_submit_link *link = &ctx->submit_state.link;
+       int ret;
 
+       ret = io_init_req(ctx, req, sqe);
+       if (unlikely(ret))
+               return io_submit_fail_init(sqe, req, ret);
+
+       trace_io_uring_submit_req(req);
+
+       if (unlikely(link->head || (req->flags & (IO_REQ_LINK_FLAGS |
+                                   REQ_F_FORCE_ASYNC | REQ_F_FAIL)))) {
+               req = io_link_sqe(link, req);
+               if (!req)
+                       return 0;
+       }
        io_queue_sqe(req);
        return 0;
 }