- for(i = 0; i < UNSHARED_PTRS_PER_PGD; i++) {
- pgd_t pgd = pgdp[i];
-
- if (pgd_val(pgd) != 0) {
- pmd_t *pmd = (pmd_t *)pgd_page_vaddr(pgd);
-
- pgdp[i] = native_make_pgd(0);
-
- paravirt_release_pd(pgd_val(pgd) >> PAGE_SHIFT);
- pmd_free(mm, pmd);
- }
- }
-}
-
-/*
- * In PAE mode, we need to do a cr3 reload (=tlb flush) when
- * updating the top-level pagetable entries to guarantee the
- * processor notices the update. Since this is expensive, and
- * all 4 top-level entries are used almost immediately in a
- * new process's life, we just pre-populate them here.
- *
- * Also, if we're in a paravirt environment where the kernel pmd is
- * not shared between pagetables (!SHARED_KERNEL_PMDS), we allocate
- * and initialize the kernel pmds here.
- */
-static int pgd_prepopulate_pmd(struct mm_struct *mm, pgd_t *pgd)
-{
- pud_t *pud;
- unsigned long addr;
- int i;
-
- pud = pud_offset(pgd, 0);
- for (addr = i = 0; i < UNSHARED_PTRS_PER_PGD;
- i++, pud++, addr += PUD_SIZE) {
- pmd_t *pmd = pmd_alloc_one(mm, addr);
-
- if (!pmd) {
- pgd_mop_up_pmds(mm, pgd);
- return 0;
- }
-
- if (i >= USER_PTRS_PER_PGD)
- memcpy(pmd, (pmd_t *)pgd_page_vaddr(swapper_pg_dir[i]),
- sizeof(pmd_t) * PTRS_PER_PMD);
-
- pud_populate(mm, pud, pmd);
- }
-
- return 1;
-}
-#else /* !CONFIG_X86_PAE */
-/* No need to prepopulate any pagetable entries in non-PAE modes. */
-static int pgd_prepopulate_pmd(struct mm_struct *mm, pgd_t *pgd)
-{
- return 1;
-}
-
-static void pgd_mop_up_pmds(struct mm_struct *mm, pgd_t *pgdp)
-{
-}
-#endif /* CONFIG_X86_PAE */
-
-pgd_t *pgd_alloc(struct mm_struct *mm)
-{
- pgd_t *pgd = (pgd_t *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
-
- /* so that alloc_pd can use it */
- mm->pgd = pgd;
- if (pgd)
- pgd_ctor(pgd);
-
- if (pgd && !pgd_prepopulate_pmd(mm, pgd)) {
- pgd_dtor(pgd);
- free_page((unsigned long)pgd);
- pgd = NULL;
- }
-
- return pgd;
-}
-
-void pgd_free(struct mm_struct *mm, pgd_t *pgd)
-{
- pgd_mop_up_pmds(mm, pgd);
- pgd_dtor(pgd);
- free_page((unsigned long)pgd);
-}
-
-void __pte_free_tlb(struct mmu_gather *tlb, struct page *pte)
-{
- pgtable_page_dtor(pte);
- paravirt_release_pt(page_to_pfn(pte));
- tlb_remove_page(tlb, pte);
-}
-
-#ifdef CONFIG_X86_PAE
-
-void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd)
-{
- paravirt_release_pd(__pa(pmd) >> PAGE_SHIFT);
- tlb_remove_page(tlb, virt_to_page(pmd));
-}
-
-#endif
-
-int pmd_bad(pmd_t pmd)
-{
- WARN_ON_ONCE(pmd_bad_v1(pmd) != pmd_bad_v2(pmd));