blk: add vector gaps queue parameter

index d6e5ba3..6483091 100644
@@ -771,7 +771,7 @@ static int __bio_add_page(struct request_queue *q, struct bio *bio, struct page
 		 * offset would create a gap, disallow it.
 		 */
 		if (q->queue_flags & (1 << QUEUE_FLAG_SG_GAPS) &&
-		    bvec_gap_to_prev(prev, offset))
+		    bvec_gap_to_prev(prev, offset, queue_virt_mask(q)))
 			return 0;
 	}
 

index 30a0d9f..4fe11cf 100644
@@ -361,7 +361,8 @@ static int req_gap_to_prev(struct request *req, struct request *next)
 	struct bio *prev = req->biotail;
 
 	return bvec_gap_to_prev(&prev->bi_io_vec[prev->bi_vcnt - 1],
-				next->bio->bi_io_vec[0].bv_offset);
+				next->bio->bi_io_vec[0].bv_offset,
+				queue_virt_mask(req->q));
 }
 
 static int ll_merge_requests_fn(struct request_queue *q, struct request *req,

@@ -594,7 +595,8 @@ bool blk_rq_merge_ok(struct request *rq, struct bio *bio)
 		struct bio_vec *bprev;
 
 		bprev = &rq->biotail->bi_io_vec[rq->biotail->bi_vcnt - 1];
-		if (bvec_gap_to_prev(bprev, bio->bi_io_vec[0].bv_offset))
+		if (bvec_gap_to_prev(bprev, bio->bi_io_vec[0].bv_offset,
+							queue_virt_mask(q)))
 			return false;
 	}
 

index 12600bf..4acd505 100644
@@ -111,6 +111,7 @@ void blk_set_default_limits(struct queue_limits *lim)
 	lim->max_segments = BLK_MAX_SEGMENTS;
 	lim->max_integrity_segments = 0;
 	lim->seg_boundary_mask = BLK_SEG_BOUNDARY_MASK;
+	lim->virt_mask = 0;
 	lim->max_segment_size = BLK_MAX_SEGMENT_SIZE;
 	lim->max_sectors = lim->max_hw_sectors = BLK_SAFE_MAX_SECTORS;
 	lim->chunk_sectors = 0;

@@ -550,7 +551,7 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
 
 	t->seg_boundary_mask = min_not_zero(t->seg_boundary_mask,
 					    b->seg_boundary_mask);
-
+	t->virt_mask = min_not_zero(t->virt_mask, b->virt_mask);
 	t->max_segments = min_not_zero(t->max_segments, b->max_segments);
 	t->max_integrity_segments = min_not_zero(t->max_integrity_segments,
 						 b->max_integrity_segments);

@@ -788,6 +789,17 @@ void blk_queue_segment_boundary(struct request_queue *q, unsigned long mask)
 EXPORT_SYMBOL(blk_queue_segment_boundary);
 
 /**
+ * blk_queue_virt_boundary - set boundary rules for bio merging
+ * @q:  the request queue for the device
+ * @mask:  the memory boundary mask
+ **/
+void blk_queue_virt_boundary(struct request_queue *q, unsigned long mask)
+{
+	q->limits.virt_mask = mask;
+}
+EXPORT_SYMBOL(blk_queue_virt_boundary);
+
+/**
  * blk_queue_dma_alignment - set dma length and memory alignment
  * @q:     the request queue for the device
  * @mask:  alignment mask

index 7920c27..1993cc8 100644
@@ -2087,6 +2087,7 @@ static void nvme_alloc_ns(struct nvme_dev *dev, unsigned nsid)
 		blk_queue_chunk_sectors(ns->queue, dev->stripe_size >> 9);
 	if (dev->vwc & NVME_CTRL_VWC_PRESENT)
 		blk_queue_flush(ns->queue, REQ_FLUSH | REQ_FUA);
+	blk_queue_virt_boundary(ns->queue, dev->page_size - 1);
 
 	disk->major = nvme_major;
 	disk->first_minor = 0;

index 5e963a6..9f906c5 100644
@@ -190,9 +190,9 @@ static inline void *bio_data(struct bio *bio)
  * Check if adding a bio_vec after bprv with offset would create a gap in
  * the SG list. Most drivers don't care about this, but some do.
  */
-static inline bool bvec_gap_to_prev(struct bio_vec *bprv, unsigned int offset)
+static inline bool bvec_gap_to_prev(struct bio_vec *bprv, unsigned int offset, unsigned long mask)
 {
-	return offset || ((bprv->bv_offset + bprv->bv_len) & (PAGE_SIZE - 1));
+	return offset || ((bprv->bv_offset + bprv->bv_len) & mask);
 }
 
 #define bio_io_error(bio) bio_endio((bio), -EIO)

index d4068c1..4e28fb5 100644
@@ -258,6 +258,7 @@ struct blk_queue_tag {
 struct queue_limits {
 	unsigned long		bounce_pfn;
 	unsigned long		seg_boundary_mask;
+	unsigned long		virt_mask;
 
 	unsigned int		max_hw_sectors;
 	unsigned int		chunk_sectors;

@@ -1154,6 +1155,11 @@ static inline unsigned long queue_segment_boundary(struct request_queue *q)
 	return q->limits.seg_boundary_mask;
 }
 
+static inline unsigned long queue_virt_mask(struct request_queue *q)
+{
+	return q->limits.virt_mask;
+}
+
 static inline unsigned int queue_max_sectors(struct request_queue *q)
 {
 	return q->limits.max_sectors;