io_uring: make HARDLINK imply LINK

The rules are as follows, if IOSQE_IO_HARDLINK is specified, then it's a
link and there is no need to set IOSQE_IO_LINK separately, though it
could be there. Add proper check and ensure that IOSQE_IO_HARDLINK
implies IOSQE_IO_LINK.
Signed-off-by: NPavel Begunkov <asml.silence@gmail.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

fs/io_uring.c

@@ -3698,7 +3698,7 @@ static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr,
 		 * If previous wasn't linked and we have a linked command,
 		 * that's the end of the chain. Submit the previous link.
 		 */
-		if (!(sqe_flags & IOSQE_IO_LINK) && link) {
+		if (!(sqe_flags & (IOSQE_IO_LINK|IOSQE_IO_HARDLINK)) && link) {
 			io_queue_link_head(link);
 			link = NULL;
 		}