block: drop virtual merging accounting

Remove virtual merge accounting.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/fs/bio.c b/fs/bio.c
index 3cba7ae..4ac7c59 100644
--- a/fs/bio.c
+++ b/fs/bio.c
@@ -350,8 +350,7 @@
 	 */
 
 	while (bio->bi_phys_segments >= q->max_phys_segments
-	       || bio->bi_hw_segments >= q->max_hw_segments
-	       || BIOVEC_VIRT_OVERSIZE(bio->bi_size)) {
+	       || bio->bi_hw_segments >= q->max_hw_segments) {
 
 		if (retried_segments)
 			return 0;
@@ -395,8 +394,7 @@
 	}
 
 	/* If we may be able to merge these biovecs, force a recount */
-	if (bio->bi_vcnt && (BIOVEC_PHYS_MERGEABLE(bvec-1, bvec) ||
-	    BIOVEC_VIRT_MERGEABLE(bvec-1, bvec)))
+	if (bio->bi_vcnt && (BIOVEC_PHYS_MERGEABLE(bvec-1, bvec)))
 		bio->bi_flags &= ~(1 << BIO_SEG_VALID);
 
 	bio->bi_vcnt++;