pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
{
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
#ifdef CONFIG_HUGETLB_SUPER_PAGES
pte_t *pte;
#endif
/* Get the top-level page table entry. */
pgd = (pgd_t *)get_pte((pte_t *)mm->pgd, pgd_index(addr), 0);
/* We don't have four levels. */
pud = pud_offset(pgd, addr);
#ifndef __PAGETABLE_PUD_FOLDED
# error support fourth page table level
#endif
if (!pud_present(*pud))
return NULL;
/* Check for an L0 huge PTE, if we have three levels. */
#ifndef __PAGETABLE_PMD_FOLDED
if (pud_huge(*pud))
return (pte_t *)pud;
pmd = (pmd_t *)get_pte((pte_t *)pud_page_vaddr(*pud),
pmd_index(addr), 1);
if (!pmd_present(*pmd))
return NULL;
#else
pmd = pmd_offset(pud, addr);
#endif
/* Check for an L1 huge PTE. */
if (pmd_huge(*pmd))
return (pte_t *)pmd;
#ifdef CONFIG_HUGETLB_SUPER_PAGES
/* Check for an L2 huge PTE. */
pte = get_pte((pte_t *)pmd_page_vaddr(*pmd), pte_index(addr), 2);
if (!pte_present(*pte))
return NULL;
if (pte_super(*pte))
return pte;
#endif
return NULL;
}
static void walk_pmd_level(struct seq_file *m, struct pg_state *st, pud_t addr,
unsigned long P)
{
int i;
pmd_t *start;
start = (pmd_t *) pud_page_vaddr(addr);
for (i = 0; i < PTRS_PER_PMD; i++) {
st->current_address = normalize_addr(P + i * PMD_LEVEL_MULT);
if (!pmd_none(*start)) {
pgprotval_t prot = pmd_val(*start) & PTE_FLAGS_MASK;
if (pmd_large(*start) || !pmd_present(*start))
note_page(m, st, __pgprot(prot), 3);
else
walk_pte_level(m, st, *start,
P + i * PMD_LEVEL_MULT);
} else
note_page(m, st, __pgprot(0), 3);
start++;
}
}
struct page *pud_page(pud_t pud)
{
if (pud_huge(pud))
return pte_page(pud_pte(pud));
return virt_to_page(pud_page_vaddr(pud));
}
