[PATCH 09/13] block: merge BIOVEC_SEG_BOUNDARY into biovec_phys_mergeable

[Christoph Hellwig <hch@lst.de>]

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

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 block/bio.c           |  4 +---
 block/blk-integrity.c | 12 ++----------
 block/blk-merge.c     | 29 +++++------------------------
 block/blk.h           | 12 +++++++++---
 include/linux/bio.h   |  8 --------
 5 files changed, 17 insertions(+), 48 deletions(-)

diff --git a/block/bio.c b/block/bio.c
index d15a228d1bfc..26f6e8deee2d 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -729,9 +729,7 @@ int bio_add_pc_page(struct request_queue *q, struct bio *bio, struct page
 	}
 
 	/* If we may be able to merge these biovecs, force a recount */
-	if (bio->bi_vcnt > 1 &&
-	    biovec_phys_mergeable(bvec - 1, bvec) &&
-	    BIOVEC_SEG_BOUNDARY(q, bvec - 1, bvec))
+	if (bio->bi_vcnt > 1 && biovec_phys_mergeable(q, bvec - 1, bvec))
 		bio_clear_flag(bio, BIO_SEG_VALID);
 
  done:
diff --git a/block/blk-integrity.c b/block/blk-integrity.c
index 0f7267916509..d1ab089e0919 100644
--- a/block/blk-integrity.c
+++ b/block/blk-integrity.c
@@ -49,12 +49,8 @@ int blk_rq_count_integrity_sg(struct request_queue *q, struct bio *bio)
 	bio_for_each_integrity_vec(iv, bio, iter) {
 
 		if (prev) {
-			if (!biovec_phys_mergeable(&ivprv, &iv))
+			if (!biovec_phys_mergeable(q, &ivprv, &iv))
 				goto new_segment;
-
-			if (!BIOVEC_SEG_BOUNDARY(q, &ivprv, &iv))
-				goto new_segment;
-
 			if (seg_size + iv.bv_len > queue_max_segment_size(q))
 				goto new_segment;
 
@@ -95,12 +91,8 @@ int blk_rq_map_integrity_sg(struct request_queue *q, struct bio *bio,
 	bio_for_each_integrity_vec(iv, bio, iter) {
 
 		if (prev) {
-			if (!biovec_phys_mergeable(&ivprv, &iv))
+			if (!biovec_phys_mergeable(q, &ivprv, &iv))
 				goto new_segment;
-
-			if (!BIOVEC_SEG_BOUNDARY(q, &ivprv, &iv))
-				goto new_segment;
-
 			if (sg->length + iv.bv_len > queue_max_segment_size(q))
 				goto new_segment;
 
diff --git a/block/blk-merge.c b/block/blk-merge.c
index 5e63e8259f92..42a46744c11b 100644
--- a/block/blk-merge.c
+++ b/block/blk-merge.c
@@ -21,9 +21,7 @@ static inline bool bios_segs_mergeable(struct request_queue *q,
 		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 @@ static struct bio *blk_bio_segment_split(struct request_queue *q,
 		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 @@ static unsigned int __blk_recalc_rq_segments(struct request_queue *q,
 				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 @@ static int blk_phys_contig_segment(struct request_queue *q, struct bio *bio,
 	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 @@ __blk_segment_map_sg(struct request_queue *q, struct bio_vec *bvec,
 	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;
diff --git a/block/blk.h b/block/blk.h
index e36395e4c686..e903ce783624 100644
--- a/block/blk.h
+++ b/block/blk.h
@@ -150,13 +150,19 @@ static inline void blk_queue_enter_live(struct request_queue *q)
 	percpu_ref_get(&q->q_usage_counter);
 }
 
-static inline bool biovec_phys_mergeable(const struct bio_vec *vec1,
-		const struct bio_vec *vec2)
+static inline bool biovec_phys_mergeable(struct request_queue *q,
+		struct bio_vec *vec1, struct bio_vec *vec2)
 {
-	if (bvec_to_phys(vec1) + vec1->bv_len != bvec_to_phys(vec2))
+	unsigned long mask = queue_segment_boundary(q);
+	phys_addr_t addr1 = bvec_to_phys(vec1);
+	phys_addr_t addr2 = bvec_to_phys(vec2);
+
+	if (addr1 + vec1->bv_len != addr2)
 		return false;
 	if (xen_domain() && !xen_biovec_phys_mergeable(vec1, vec2))
 		return false;
+	if ((addr1 | mask) != ((addr2 + vec2->bv_len - 1) | mask))
+		return false;
 	return true;
 }
 
diff --git a/include/linux/bio.h b/include/linux/bio.h
index e3d0abb694d4..8bec9f248ab8 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -137,14 +137,6 @@ static inline bool bio_full(struct bio *bio)
  */
 #define bvec_to_phys(bv)	(page_to_phys((bv)->bv_page) + (unsigned long) (bv)->bv_offset)
 
-/*
- * merge helpers etc
- */
-#define __BIO_SEG_BOUNDARY(addr1, addr2, mask) \
-	(((addr1) | (mask)) == (((addr2) - 1) | (mask)))
-#define BIOVEC_SEG_BOUNDARY(q, b1, b2) \
-	__BIO_SEG_BOUNDARY(bvec_to_phys((b1)), bvec_to_phys((b2)) + (b2)->bv_len, queue_segment_boundary((q)))
-
 /*
  * drivers should _never_ use the all version - the bio may have been split
  * before it got to the driver and the driver won't own all of it
-- 
2.18.0