LUO_FLB_PGCNT
#define LUO_FLB_MAX (((LUO_FLB_PGCNT << PAGE_SHIFT) - \
header_ser = kho_alloc_preserve(LUO_FLB_PGCNT << PAGE_SHIFT);
header_ser->pgcnt = LUO_FLB_PGCNT;