io_uring: ensure read requests go through -ERESTART* transformation

We need to call kiocb_done() for any ret < 0 to ensure that we always
get the proper -ERESTARTSYS (and friends) transformation done.

At some point this should be tied into general error handling, so we
can get rid of the various (mostly network) related commands that check
and perform this substitution.
Signed-off-by: Jens Axboe <axboe@kernel.dk>

fs/io_uring.c

@@ -3160,7 +3160,8 @@ static int io_read(struct io_kiocb *req, bool force_nonblock,
 			goto out_free;
 		return -EAGAIN;
 	} else if (ret < 0) {
-		goto out_free;
+		/* make sure -ERESTARTSYS -> -EINTR is done */
+		goto done;
 	}
 
 	/* read it all, or we did blocking attempt. no retry. */