AMD64_NBPDR
return (AMD64_NBPDR - (va & AMD64_PDRMASK));
#define AMD64_PDRMASK (AMD64_NBPDR - 1)
_Static_assert(NBPDR == AMD64_NBPDR, "NBPDR mismatch");
_amd64_entry_to_prot(pde), AMD64_NBPDR, pgsz)) {