io_uring/rw: cleanup retry path

We no longer need to gate a potential retry on whether or not the
context matches our original task, as all read/write operations have
been fully prepared upfront. This means there's never any re-import
needed, and hence we can always retry requests.

Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/io_uring/rw.c b/io_uring/rw.c
index 9743df5617fd71d8628aa0f2c76934996ea7846e..ab4454aa8e30dac6306d7d05709ebdd172cb115a 100644 (file)
--- a/io_uring/rw.c
+++ b/io_uring/rw.c
@@ -369,16 +369,9 @@ static inline loff_t *io_kiocb_update_pos(struct io_kiocb *req)
        return NULL;
 }
 
-#ifdef CONFIG_BLOCK
-static void io_resubmit_prep(struct io_kiocb *req)
-{
-       struct io_async_rw *io = req->async_data;
-
-       iov_iter_restore(&io->iter, &io->iter_state);
-}
-
 static bool io_rw_should_reissue(struct io_kiocb *req)
 {
+#ifdef CONFIG_BLOCK
        umode_t mode = file_inode(req->file)->i_mode;
        struct io_ring_ctx *ctx = req->ctx;
 
@@ -394,23 +387,11 @@ static bool io_rw_should_reissue(struct io_kiocb *req)
         */
        if (percpu_ref_is_dying(&ctx->refs))
                return false;
-       /*
-        * Play it safe and assume not safe to re-import and reissue if we're
-        * not in the original thread group (or in task context).
-        */
-       if (!same_thread_group(req->task, current) || !in_task())
-               return false;
        return true;
-}
 #else
-static void io_resubmit_prep(struct io_kiocb *req)
-{
-}
-static bool io_rw_should_reissue(struct io_kiocb *req)
-{
        return false;
-}
 #endif
+}
 
 static void io_req_end_write(struct io_kiocb *req)
 {
@@ -575,8 +556,10 @@ static int kiocb_done(struct io_kiocb *req, ssize_t ret,
        }
 
        if (req->flags & REQ_F_REISSUE) {
+               struct io_async_rw *io = req->async_data;
+
                req->flags &= ~REQ_F_REISSUE;
-               io_resubmit_prep(req);
+               iov_iter_restore(&io->iter, &io->iter_state);
                return -EAGAIN;
        }
        return IOU_ISSUE_SKIP_COMPLETE;
@@ -897,9 +880,8 @@ int io_read(struct io_kiocb *req, unsigned int issue_flags)
        int ret;
 
        ret = __io_read(req, issue_flags);
-       if (ret >= 0) {
-               ret = kiocb_done(req, ret, issue_flags);
-       }
+       if (ret >= 0)
+               return kiocb_done(req, ret, issue_flags);
 
        return ret;
 }
@@ -1061,7 +1043,7 @@ int io_write(struct io_kiocb *req, unsigned int issue_flags)
                        return -EAGAIN;
                }
 done:
-               ret = kiocb_done(req, ret2, issue_flags);
+               return kiocb_done(req, ret2, issue_flags);
        } else {
 ret_eagain:
                iov_iter_restore(&io->iter, &io->iter_state);
@@ -1069,7 +1051,6 @@ ret_eagain:
                        io_req_end_write(req);
                return -EAGAIN;
        }
-       return ret;
 }
 
 void io_rw_fail(struct io_kiocb *req)