+#include <asm/pgtable.h>
+#include <asm/tlbflush.h>
+
+static void msync_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
+ unsigned long addr, unsigned long end)
+{
+ pte_t *pte;
+ spinlock_t *ptl;
+ int progress = 0;
+
+again:
+ pte = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl);
+ do {
+ struct page *page;
+
+ if (progress >= 64) {
+ progress = 0;
+ if (need_resched() || need_lockbreak(ptl))
+ break;
+ }
+ progress++;
+ if (!pte_present(*pte))
+ continue;
+ if (!pte_maybe_dirty(*pte))
+ continue;
+ page = vm_normal_page(vma, addr, *pte);
+ if (!page)
+ continue;
+ if (ptep_clear_flush_dirty(vma, addr, pte) ||
+ page_test_and_clear_dirty(page))
+ set_page_dirty(page);
+ progress += 3;
+ } while (pte++, addr += PAGE_SIZE, addr != end);
+ pte_unmap_unlock(pte - 1, ptl);
+ cond_resched();
+ if (addr != end)
+ goto again;
+}
+
+static inline void msync_pmd_range(struct vm_area_struct *vma, pud_t *pud,
+ unsigned long addr, unsigned long end)
+{
+ pmd_t *pmd;
+ unsigned long next;
+
+ pmd = pmd_offset(pud, addr);
+ do {
+ next = pmd_addr_end(addr, end);
+ if (pmd_none_or_clear_bad(pmd))
+ continue;
+ msync_pte_range(vma, pmd, addr, next);
+ } while (pmd++, addr = next, addr != end);
+}
+
+static inline void msync_pud_range(struct vm_area_struct *vma, pgd_t *pgd,
+ unsigned long addr, unsigned long end)
+{
+ pud_t *pud;
+ unsigned long next;
+
+ pud = pud_offset(pgd, addr);
+ do {
+ next = pud_addr_end(addr, end);
+ if (pud_none_or_clear_bad(pud))
+ continue;
+ msync_pmd_range(vma, pud, addr, next);
+ } while (pud++, addr = next, addr != end);
+}
+
+static void msync_page_range(struct vm_area_struct *vma,
+ unsigned long addr, unsigned long end)
+{
+ pgd_t *pgd;
+ unsigned long next;
+
+ /* For hugepages we can't go walking the page table normally,
+ * but that's ok, hugetlbfs is memory based, so we don't need
+ * to do anything more on an msync().
+ */
+ if (vma->vm_flags & VM_HUGETLB)
+ return;
+
+ BUG_ON(addr >= end);
+ pgd = pgd_offset(vma->vm_mm, addr);
+ flush_cache_range(vma, addr, end);
+ do {
+ next = pgd_addr_end(addr, end);
+ if (pgd_none_or_clear_bad(pgd))
+ continue;
+ msync_pud_range(vma, pgd, addr, next);
+ } while (pgd++, addr = next, addr != end);
+}
+