block: merge BIOVEC_SEG_BOUNDARY into biovec_phys_mergeable

These two checks should always be performed together, so merge them into
a single helper.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/block/blk-merge.c b/block/blk-merge.c
index 5e63e82..42a4674 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -21,9 +21,7 @@
 		struct bio *prev, struct bio_vec *prev_last_bv,
 		struct bio_vec *next_first_bv)
 {
-	if (!biovec_phys_mergeable(prev_last_bv, next_first_bv))
-		return false;
-	if (!BIOVEC_SEG_BOUNDARY(q, prev_last_bv, next_first_bv))
+	if (!biovec_phys_mergeable(q, prev_last_bv, next_first_bv))
 		return false;
 	if (prev->bi_seg_back_size + next_first_bv->bv_len >
 			queue_max_segment_size(q))
@@ -199,9 +197,7 @@
 		if (bvprvp && blk_queue_cluster(q)) {
 			if (seg_size + bv.bv_len > queue_max_segment_size(q))
 				goto new_segment;
-			if (!biovec_phys_mergeable(bvprvp, &bv))
-				goto new_segment;
-			if (!BIOVEC_SEG_BOUNDARY(q, bvprvp, &bv))
+			if (!biovec_phys_mergeable(q, bvprvp, &bv))
 				goto new_segment;
 
 			seg_size += bv.bv_len;
@@ -332,9 +328,7 @@
 				if (seg_size + bv.bv_len
 				    > queue_max_segment_size(q))
 					goto new_segment;
-				if (!biovec_phys_mergeable(&bvprv, &bv))
-					goto new_segment;
-				if (!BIOVEC_SEG_BOUNDARY(q, &bvprv, &bv))
+				if (!biovec_phys_mergeable(q, &bvprv, &bv))
 					goto new_segment;
 
 				seg_size += bv.bv_len;
@@ -414,17 +408,7 @@
 	bio_get_last_bvec(bio, &end_bv);
 	bio_get_first_bvec(nxt, &nxt_bv);
 
-	if (!biovec_phys_mergeable(&end_bv, &nxt_bv))
-		return 0;
-
-	/*
-	 * bio and nxt are contiguous in memory; check if the queue allows
-	 * these two to be merged into one
-	 */
-	if (BIOVEC_SEG_BOUNDARY(q, &end_bv, &nxt_bv))
-		return 1;
-
-	return 0;
+	return biovec_phys_mergeable(q, &end_bv, &nxt_bv);
 }
 
 static inline void
@@ -438,10 +422,7 @@
 	if (*sg && *cluster) {
 		if ((*sg)->length + nbytes > queue_max_segment_size(q))
 			goto new_segment;
-
-		if (!biovec_phys_mergeable(bvprv, bvec))
-			goto new_segment;
-		if (!BIOVEC_SEG_BOUNDARY(q, bvprv, bvec))
+		if (!biovec_phys_mergeable(q, bvprv, bvec))
 			goto new_segment;
 
 		(*sg)->length += nbytes;