- unsigned long haddr = address & HPAGE_PMD_MASK;
- spinlock_t *ptl;
- pgd_t *pgd;
- pud_t *pud;
- pmd_t *pmd;
- pte_t *pte;
- int i, nr = HPAGE_PMD_NR;
-
- /* Skip pages which doesn't belong to the VMA */
- if (address < vma->vm_start) {
- int off = (vma->vm_start - address) >> PAGE_SHIFT;
- page += off;
- nr -= off;
- address = vma->vm_start;
- }
-
- pgd = pgd_offset(vma->vm_mm, address);
- if (!pgd_present(*pgd))
- return;
- pud = pud_offset(pgd, address);
- if (!pud_present(*pud))
- return;
- pmd = pmd_offset(pud, address);
- ptl = pmd_lock(vma->vm_mm, pmd);
- if (!pmd_present(*pmd)) {
- spin_unlock(ptl);
- return;
- }
- if (pmd_trans_huge(*pmd)) {
- if (page == pmd_page(*pmd))
- __split_huge_pmd_locked(vma, pmd, haddr, true);
- spin_unlock(ptl);
- return;
- }
- spin_unlock(ptl);
-
- pte = pte_offset_map_lock(vma->vm_mm, pmd, address, &ptl);
- for (i = 0; i < nr; i++, address += PAGE_SIZE, page++, pte++) {
- pte_t entry, swp_pte;
- swp_entry_t swp_entry;
-
- /*
- * We've just crossed page table boundary: need to map next one.
- * It can happen if THP was mremaped to non PMD-aligned address.
- */
- if (unlikely(address == haddr + HPAGE_PMD_SIZE)) {
- pte_unmap_unlock(pte - 1, ptl);
- pmd = mm_find_pmd(vma->vm_mm, address);
- if (!pmd)
- return;
- pte = pte_offset_map_lock(vma->vm_mm, pmd,
- address, &ptl);
- }
-
- if (!pte_present(*pte))
- continue;
- if (page_to_pfn(page) != pte_pfn(*pte))
- continue;
- flush_cache_page(vma, address, page_to_pfn(page));
- entry = ptep_clear_flush(vma, address, pte);
- if (pte_dirty(entry))
- SetPageDirty(page);
- swp_entry = make_migration_entry(page, pte_write(entry));
- swp_pte = swp_entry_to_pte(swp_entry);
- if (pte_soft_dirty(entry))
- swp_pte = pte_swp_mksoft_dirty(swp_pte);
- set_pte_at(vma->vm_mm, address, pte, swp_pte);
- page_remove_rmap(page, false);
- put_page(page);
- }
- pte_unmap_unlock(pte - 1, ptl);
-}
-
-static void freeze_page(struct anon_vma *anon_vma, struct page *page)
-{
- struct anon_vma_chain *avc;
- pgoff_t pgoff = page_to_pgoff(page);