static int pt_populate_pml2(pte_t *pml2, virt_t from, virt_t to, pte_t flags)
{
virt_t vaddr = from;
for (int i = pml2_i(from); vaddr != to; ++i) {
const virt_t bytes =
MINU(PML1_SIZE - (vaddr & PML1_MASK), to - vaddr);
const pfn_t pages = bytes >> PAGE_BITS;
if (!pte_present(pml2[i]) && !pte_large(flags)) {
struct page *pt = alloc_page_table(flags);
if (!pt) {
pt_release_pml2(pml2, from, vaddr);
return -ENOMEM;
}
pt->u.refcount += pages;
pml2[i] = page_paddr(pt) | flags;
} else if (pte_present(pml2[i]) && !pte_large(pml2[i])) {
const pfn_t pfn = pte_phys(pml2[i]) >> PAGE_BITS;
struct page *pt = pfn2page(pfn);
pt->u.refcount += pages;
}
vaddr += bytes;
}
return 0;
}
struct pt_iter *pt_iter_next(struct pt_iter *iter)
{
int level = iter->level;
int idx = iter->idx[level];
while (idx == PT_SIZE - 1 && level != PT_MAX_LEVEL)
idx = iter->idx[++level];
if (idx == PT_SIZE - 1)
return 0;
pte_t pte = iter->pt[level][++idx];
iter->idx[level] = idx;
while (pte_present(pte) && level != 0 && !pte_large(pte)) {
const phys_t paddr = pte_phys(pte);
pte_t *pt = va(paddr);
iter->idx[--level] = 0;
iter->pt[level] = pt;
pte = pt[0];
}
iter->level = level;
while (level != 0) {
iter->pt[--level] = 0;
iter->idx[level] = 0;
}
iter->addr = pt_iter_addr(iter);
return iter;
}
struct pt_iter *pt_iter_set(struct pt_iter *iter, pte_t *pml4, virt_t addr)
{
memset(iter, 0, sizeof(*iter));
if (!pml4)
return iter;
int level = PT_MAX_LEVEL;
int idx = pml4_i(addr);
pte_t pte = pml4[idx];
iter->pt[level] = pml4;
iter->idx[level] = idx;
while (pte_present(pte) && level != 0 && !pte_large(pte)) {
const phys_t paddr = pte_phys(pte);
pte_t *pt = va(paddr);
idx = pt_index(addr, level--);
pte = pt[idx];
iter->idx[level] = idx;
iter->pt[level] = pt;
}
iter->addr = pt_iter_addr(iter);
iter->level = level;
return iter;
}
bool pt_iter_large(const struct pt_iter *iter)
{
const int level = iter->level;
const int index = iter->idx[level];
return pte_large(iter->pt[level][index]);
}
phys_t get_phys_adr(virt_t vad) {
phys_t pad;
pte_t *pml4e = pml4 + pml4_i(vad);
pte_t *pdpte = ((pte_t *) va(pte_phys(*pml4e) << 12)) + pml3_i(vad);
pte_t *pde = ((pte_t *) va(pte_phys(*pdpte) << 12)) + pml2_i(vad);
if (pte_large(*pde)) {
pad = ((*pde & (~((1 << 21) - 1)))) | (vad & ((1 << 21) - 1));
return pad;
}
pte_t *pte = ((pte_t *) va(pte_phys(*pde) << 12)) + pml1_i(vad);
pad = ((*pte & (~((1 << 12) - 1)))) | (vad & ((1 << 12) - 1));;
return pad;
}
static void pt_release_pml2(pte_t *pml2, virt_t from, virt_t to)
{
virt_t vaddr = from;
for (int i = pml2_i(from); vaddr != to; ++i) {
const pte_t pte = pml2[i];
const virt_t bytes =
MINU(PML1_SIZE - (vaddr & PML1_MASK), to - vaddr);
const pfn_t pages = bytes >> PAGE_BITS;
if (pte_present(pte) && !pte_large(pte)) {
const pfn_t pfn = pte_phys(pte) >> PAGE_BITS;
struct page *pt = pfn2page(pfn);
pt->u.refcount -= pages;
if (pt->u.refcount == 0) {
pml2[i] = 0;
free_page_table(pt);
}
}
vaddr += bytes;
}
}
