fs: simplify dio_bio_complete

Only read bio->bi_error once in the common path.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NBart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

fs/direct-io.c

@@ -477,13 +477,12 @@ static int dio_bio_complete(struct dio *dio, struct bio *bio)
 {
 	struct bio_vec *bvec;
 	unsigned i;
-	int err;
+	int err = bio->bi_error;
 
-	if (bio->bi_error)
+	if (err)
 		dio->io_error = -EIO;
 
 	if (dio->is_async && dio->op == REQ_OP_READ && dio->should_dirty) {
-		err = bio->bi_error;
 		bio_check_pages_dirty(bio);	/* transfers ownership */
 	} else {
 		bio_for_each_segment_all(bvec, bio, i) {
@@ -494,7 +493,6 @@ static int dio_bio_complete(struct dio *dio, struct bio *bio)
 				set_page_dirty_lock(page);
 			put_page(page);
 		}
-		err = bio->bi_error;
 		bio_put(bio);
 	}
 	return err;