block: simplify BIOVEC_PHYS_MERGEABLE

Turn the macro into an inline, move it to blk.h and simplify the
arch hooks a bit.

Also rename the function to biovec_phys_mergeable as there is no need
to shout.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

arch/arm/include/asm/io.h

@@ -469,9 +469,8 @@ extern void pci_iounmap(struct pci_dev *dev, void __iomem *addr);
 struct bio_vec;
 extern bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
 				      const struct bio_vec *vec2);
-#define BIOVEC_PHYS_MERGEABLE(vec1, vec2)				\
-	(__BIOVEC_PHYS_MERGEABLE(vec1, vec2) &&				\
-	 (!xen_domain() || xen_biovec_phys_mergeable(vec1, vec2)))
+#define ARCH_BIOVEC_PHYS_MERGEABLE(vec1, vec2)				\
+	 (!xen_domain() || xen_biovec_phys_mergeable(vec1, vec2))
 
 #ifdef CONFIG_MMU
 #define ARCH_HAS_VALID_PHYS_ADDR_RANGE

arch/arm64/include/asm/io.h

@@ -208,9 +208,8 @@ extern int devmem_is_allowed(unsigned long pfn);
 struct bio_vec;
 extern bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
 				      const struct bio_vec *vec2);
-#define BIOVEC_PHYS_MERGEABLE(vec1, vec2)				\
-	(__BIOVEC_PHYS_MERGEABLE(vec1, vec2) &&				\
-	 (!xen_domain() || xen_biovec_phys_mergeable(vec1, vec2)))
+#define ARCH_BIOVEC_PHYS_MERGEABLE(vec1, vec2)				\
+	 (!xen_domain() || xen_biovec_phys_mergeable(vec1, vec2))
 
 #endif	/* __KERNEL__ */
 #endif	/* __ASM_IO_H */

arch/x86/include/asm/io.h

@@ -376,9 +376,8 @@ struct bio_vec;
 extern bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
 				      const struct bio_vec *vec2);
 
-#define BIOVEC_PHYS_MERGEABLE(vec1, vec2)				\
-	(__BIOVEC_PHYS_MERGEABLE(vec1, vec2) &&				\
-	 (!xen_domain() || xen_biovec_phys_mergeable(vec1, vec2)))
+#define ARCH_BIOVEC_PHYS_MERGEABLE(vec1, vec2)				\
+	 (!xen_domain() || xen_biovec_phys_mergeable(vec1, vec2))
 #endif	/* CONFIG_XEN */
 
 #define IO_SPACE_LIMIT 0xffff

block/bio.c

@@ -731,7 +731,7 @@ 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)))
+	if (bio->bi_vcnt > 1 && biovec_phys_mergeable(bvec-1, bvec))
 		bio_clear_flag(bio, BIO_SEG_VALID);
 
  done:

block/blk-integrity.c

@@ -49,7 +49,7 @@ 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(&ivprv, &iv))
 				goto new_segment;
 
 			if (!BIOVEC_SEG_BOUNDARY(q, &ivprv, &iv))
@@ -95,7 +95,7 @@ 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(&ivprv, &iv))
 				goto new_segment;
 
 			if (!BIOVEC_SEG_BOUNDARY(q, &ivprv, &iv))

block/blk-merge.c

@@ -21,7 +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))
+	if (!biovec_phys_mergeable(prev_last_bv, next_first_bv))
 		return false;
 	if (!BIOVEC_SEG_BOUNDARY(q, prev_last_bv, next_first_bv))
 		return false;
@@ -199,7 +199,7 @@ 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))
+			if (!biovec_phys_mergeable(bvprvp, &bv))
 				goto new_segment;
 			if (!BIOVEC_SEG_BOUNDARY(q, bvprvp, &bv))
 				goto new_segment;
@@ -332,7 +332,7 @@ 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))
+				if (!biovec_phys_mergeable(&bvprv, &bv))
 					goto new_segment;
 				if (!BIOVEC_SEG_BOUNDARY(q, &bvprv, &bv))
 					goto new_segment;
@@ -414,7 +414,7 @@ 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))
+	if (!biovec_phys_mergeable(&end_bv, &nxt_bv))
 		return 0;
 
 	/*
@@ -439,7 +439,7 @@ __blk_segment_map_sg(struct request_queue *q, struct bio_vec *bvec,
 		if ((*sg)->length + nbytes > queue_max_segment_size(q))
 			goto new_segment;
 
-		if (!BIOVEC_PHYS_MERGEABLE(bvprv, bvec))
+		if (!biovec_phys_mergeable(bvprv, bvec))
 			goto new_segment;
 		if (!BIOVEC_SEG_BOUNDARY(q, bvprv, bvec))
 			goto new_segment;

block/blk.h

@@ -149,6 +149,20 @@ static inline void blk_queue_enter_live(struct request_queue *q)
 	percpu_ref_get(&q->q_usage_counter);
 }
 
+#ifndef ARCH_BIOVEC_PHYS_MERGEABLE
+#define ARCH_BIOVEC_PHYS_MERGEABLE(vec1, vec2) true
+#endif
+
+static inline bool biovec_phys_mergeable(const struct bio_vec *vec1,
+		const struct bio_vec *vec2)
+{
+	if (bvec_to_phys(vec1) + vec1->bv_len != bvec_to_phys(vec2))
+		return false;
+	if (!ARCH_BIOVEC_PHYS_MERGEABLE(vec1, vec2))
+		return false;
+	return true;
+}
+
 static inline bool __bvec_gap_to_prev(struct request_queue *q,
 		struct bio_vec *bprv, unsigned int offset)
 {

include/linux/bio.h

@@ -140,19 +140,6 @@ static inline bool bio_full(struct bio *bio)
 /*
  * merge helpers etc
  */
-
-/* Default implementation of BIOVEC_PHYS_MERGEABLE */
-#define __BIOVEC_PHYS_MERGEABLE(vec1, vec2)	\
-	((bvec_to_phys((vec1)) + (vec1)->bv_len) == bvec_to_phys((vec2)))
-
-/*
- * allow arch override, for eg virtualized architectures (put in asm/io.h)
- */
-#ifndef BIOVEC_PHYS_MERGEABLE
-#define BIOVEC_PHYS_MERGEABLE(vec1, vec2)	\
-	__BIOVEC_PHYS_MERGEABLE(vec1, vec2)
-#endif
-
 #define __BIO_SEG_BOUNDARY(addr1, addr2, mask) \
 	(((addr1) | (mask)) == (((addr2) - 1) | (mask)))
 #define BIOVEC_SEG_BOUNDARY(q, b1, b2) \