sb_zone_number
sb_zone = sb_zone_number(zone_sectors_shift + SECTOR_SHIFT, mirror);
sb_zone = sb_zone_number(shift, i);
sb_zone = sb_zone_number(zone_info->zone_size_shift, i);
sb_zone = sb_zone_number(zone_sectors_shift + SECTOR_SHIFT, mirror);
zone_num = sb_zone_number(zinfo->zone_size_shift, mirror);
zone_num = sb_zone_number(zinfo->zone_size_shift, mirror);