[PATCH] Fix odd code in bio_add_page

From: Neil Brown <neilb@cse.unsw.edu.au>

With the current code in bio_add_page, if fail_segments is ever set, it
stays set, so bio_add_page will eventually fail having recounted the
segmentation once.

I don't think this is intended.  This patch changes the code to allow
success if the recounting the segments helps.

(Jens has acked this)

fs/bio.c

@@ -296,7 +296,7 @@ int bio_add_page(struct bio *bio, struct page *page, unsigned int len,
 		 unsigned int offset)
 {
 	request_queue_t *q = bdev_get_queue(bio->bi_bdev);
-	int fail_segments = 0, retried_segments = 0;
+	int retried_segments = 0;
 	struct bio_vec *bvec;
 
 	/*
@@ -315,18 +315,15 @@ int bio_add_page(struct bio *bio, struct page *page, unsigned int len,
 	 * we might lose a segment or two here, but rather that than
 	 * make this too complex.
 	 */
-retry_segments:
-	if (bio_phys_segments(q, bio) >= q->max_phys_segments
-	    || bio_hw_segments(q, bio) >= q->max_hw_segments)
-		fail_segments = 1;
 
-	if (fail_segments) {
+	while (bio_phys_segments(q, bio) >= q->max_phys_segments
+	    || bio_hw_segments(q, bio) >= q->max_hw_segments) {
+
 		if (retried_segments)
 			return 0;
 
 		bio->bi_flags &= ~(1 << BIO_SEG_VALID);
 		retried_segments = 1;
-		goto retry_segments;
 	}
 
 	/*