--- c2cb7b87b440dce777d92bb6c215d1c82efddbe1
+++ 6c2a35b42d42279b894358874bfd08a4558695f0
@@ -493,7 +493,7 @@ static int raid10_mergeable_bvec(struct
  */
 static int read_balance(conf_t *conf, r10bio_t *r10_bio)
 {
-	const unsigned long this_sector = r10_bio->sector;
+	const sector_t this_sector = r10_bio->sector;
 	int disk, slot, nslot;
 	const int sectors = r10_bio->sectors;
 	sector_t new_distance, current_distance;
@@ -1155,13 +1155,17 @@ static int raid10_add_disk(mddev_t *mdde
 
 			disk_stack_limits(mddev->gendisk, rdev->bdev,
 					  rdev->data_offset << 9);
-			/* as we don't honour merge_bvec_fn, we must never risk
-			 * violating it, so limit ->max_sector to one PAGE, as
-			 * a one page request is never in violation.
+			/* as we don't honour merge_bvec_fn, we must
+			 * never risk violating it, so limit
+			 * ->max_phys_segments to one lying with a single
+			 * page, as a one page request is never in
+			 * violation.
 			 */
-			if (rdev->bdev->bd_disk->queue->merge_bvec_fn &&
-			    queue_max_sectors(mddev->queue) > (PAGE_SIZE>>9))
-				blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9);
+			if (rdev->bdev->bd_disk->queue->merge_bvec_fn) {
+				blk_queue_max_phys_segments(mddev->queue, 1);
+				blk_queue_segment_boundary(mddev->queue,
+							   PAGE_CACHE_SIZE - 1);
+			}
 
 			p->head_position = 0;
 			rdev->raid_disk = mirror;
@@ -2155,12 +2159,14 @@ static int run(mddev_t *mddev)
 		disk_stack_limits(mddev->gendisk, rdev->bdev,
 				  rdev->data_offset << 9);
 		/* as we don't honour merge_bvec_fn, we must never risk
-		 * violating it, so limit ->max_sector to one PAGE, as
-		 * a one page request is never in violation.
+		 * violating it, so limit max_phys_segments to 1 lying
+		 * within a single page.
 		 */
-		if (rdev->bdev->bd_disk->queue->merge_bvec_fn &&
-		    queue_max_sectors(mddev->queue) > (PAGE_SIZE>>9))
-			blk_queue_max_sectors(mddev->queue, PAGE_SIZE>>9);
+		if (rdev->bdev->bd_disk->queue->merge_bvec_fn) {
+			blk_queue_max_phys_segments(mddev->queue, 1);
+			blk_queue_segment_boundary(mddev->queue,
+						   PAGE_CACHE_SIZE - 1);
+		}
 
 		disk->head_position = 0;
 	}