/*
         * Convert sectors to bytes.
         */
-       rs->md.bitmap_info.chunksize = (region_size << 9);
+       rs->md.bitmap_info.chunksize = to_bytes(region_size);
 
        return 0;
 }
 static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits)
 {
        struct raid_set *rs = ti->private;
-       unsigned int chunk_size = rs->md.chunk_sectors << 9;
-       struct r5conf *conf = rs->md.private;
+       unsigned int chunk_size = to_bytes(rs->md.chunk_sectors);
 
        blk_limits_io_min(limits, chunk_size);
-       blk_limits_io_opt(limits, chunk_size * (conf->raid_disks - conf->max_degraded));
+       blk_limits_io_opt(limits, chunk_size * mddev_data_stripes(rs));
 }
 
 static void raid_presuspend(struct dm_target *ti)