ptrs_per_pgd
int ptrs_per_pgd;
ptrs_per_pgd = min((1 << (BITS_PER_LONG - PGDIR_SHIFT)), PTRS_PER_PGD);
for ( ; (i < ptrs_per_pgd) && (vaddr < end); pgd++, i++) {
size_t nr_pages = vm_page_align(vm, ptrs_per_pgd(vm) * 8) / vm->page_size;
for (pgd = vm->mmu.pgd; pgd < vm->mmu.pgd + ptrs_per_pgd(vm) * 8; pgd += 8) {