diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index fd86b37..4d8c2e0 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -1018,7 +1018,7 @@
 	md_write_start(mddev, bio); /* wait on superblock update early */
 
 	if (bio_data_dir(bio) == WRITE &&
-	    bio->bi_sector + bio->bi_size/512 > mddev->suspend_lo &&
+	    bio_end_sector(bio) > mddev->suspend_lo &&
 	    bio->bi_sector < mddev->suspend_hi) {
 		/* As the suspend_* range is controlled by
 		 * userspace, we want an interruptible
@@ -1029,7 +1029,7 @@
 			flush_signals(current);
 			prepare_to_wait(&conf->wait_barrier,
 					&w, TASK_INTERRUPTIBLE);
-			if (bio->bi_sector + bio->bi_size/512 <= mddev->suspend_lo ||
+			if (bio_end_sector(bio) <= mddev->suspend_lo ||
 			    bio->bi_sector >= mddev->suspend_hi)
 				break;
 			schedule();