[PATCH for-next 2/2] io_uring/rw: don't lose short results on io_setup_async_rw()

[Pavel Begunkov <asml.silence@gmail.com>]

If a retry io_setup_async_rw() fails we lose result from the first
io_iter_do_read(), which is a problem mostly for streams/sockets.

Cc: stable@vger.kernel.org
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
---
 io_uring/rw.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/io_uring/rw.c b/io_uring/rw.c
index c562203d7a67..722c06026701 100644
--- a/io_uring/rw.c
+++ b/io_uring/rw.c
@@ -794,10 +794,12 @@ int io_read(struct io_kiocb *req, unsigned int issue_flags)
 	iov_iter_restore(&s->iter, &s->iter_state);
 
 	ret2 = io_setup_async_rw(req, iovec, s, true);
-	if (ret2)
-		return ret2;
-
 	iovec = NULL;
+	if (ret2) {
+		ret = ret > 0 ? ret : ret2;
+		goto done;
+	}
+
 	io = req->async_data;
 	s = &io->s;
 	/*
-- 
2.37.2