1 files changed, 73 insertions, 8 deletions

diff --git a/mm/rmap.c b/mm/rmap.c
index 882a85826bb..e2155d791d9 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -434,6 +434,71 @@ int page_referenced(struct page *page, int is_locked)
 	return referenced;
 }
 
+static int page_mkclean_one(struct page *page, struct vm_area_struct *vma)
+{
+	struct mm_struct *mm = vma->vm_mm;
+	unsigned long address;
+	pte_t *pte, entry;
+	spinlock_t *ptl;
+	int ret = 0;
+
+	address = vma_address(page, vma);
+	if (address == -EFAULT)
+		goto out;
+
+	pte = page_check_address(page, mm, address, &ptl);
+	if (!pte)
+		goto out;
+
+	if (!pte_dirty(*pte) && !pte_write(*pte))
+		goto unlock;
+
+	entry = ptep_get_and_clear(mm, address, pte);
+	entry = pte_mkclean(entry);
+	entry = pte_wrprotect(entry);
+	ptep_establish(vma, address, pte, entry);
+	lazy_mmu_prot_update(entry);
+	ret = 1;
+
+unlock:
+	pte_unmap_unlock(pte, ptl);
+out:
+	return ret;
+}
+
+static int page_mkclean_file(struct address_space *mapping, struct page *page)
+{
+	pgoff_t pgoff = page->index << (PAGE_CACHE_SHIFT - PAGE_SHIFT);
+	struct vm_area_struct *vma;
+	struct prio_tree_iter iter;
+	int ret = 0;
+
+	BUG_ON(PageAnon(page));
+
+	spin_lock(&mapping->i_mmap_lock);
+	vma_prio_tree_foreach(vma, &iter, &mapping->i_mmap, pgoff, pgoff) {
+		if (vma->vm_flags & VM_SHARED)
+			ret += page_mkclean_one(page, vma);
+	}
+	spin_unlock(&mapping->i_mmap_lock);
+	return ret;
+}
+
+int page_mkclean(struct page *page)
+{
+	int ret = 0;
+
+	BUG_ON(!PageLocked(page));
+
+	if (page_mapped(page)) {
+		struct address_space *mapping = page_mapping(page);
+		if (mapping)
+			ret = page_mkclean_file(mapping, page);
+	}
+
+	return ret;
+}
+
 /**
  * page_set_anon_rmap - setup new anonymous rmap
  * @page:	the page to add the mapping to
@@ -455,7 +520,7 @@ static void __page_set_anon_rmap(struct page *page,
 	 * nr_mapped state can be updated without turning off
 	 * interrupts because it is not modified via interrupt.
 	 */
-	__inc_page_state(nr_mapped);
+	__inc_zone_page_state(page, NR_ANON_PAGES);
 }
 
 /**
@@ -499,7 +564,7 @@ void page_add_new_anon_rmap(struct page *page,
 void page_add_file_rmap(struct page *page)
 {
 	if (atomic_inc_and_test(&page->_mapcount))
-		__inc_page_state(nr_mapped);
+		__inc_zone_page_state(page, NR_FILE_MAPPED);
 }
 
 /**
@@ -531,7 +596,8 @@ void page_remove_rmap(struct page *page)
 		 */
 		if (page_test_and_clear_dirty(page))
 			set_page_dirty(page);
-		__dec_page_state(nr_mapped);
+		__dec_zone_page_state(page,
+				PageAnon(page) ? NR_ANON_PAGES : NR_FILE_MAPPED);
 	}
 }
 
@@ -562,9 +628,8 @@ static int try_to_unmap_one(struct page *page, struct vm_area_struct *vma,
 	 * If it's recently referenced (perhaps page_referenced
 	 * skipped over this mm) then we should reactivate it.
 	 */
-	if ((vma->vm_flags & VM_LOCKED) ||
-			(ptep_clear_flush_young(vma, address, pte)
-				&& !migration)) {
+	if (!migration && ((vma->vm_flags & VM_LOCKED) ||
+			(ptep_clear_flush_young(vma, address, pte)))) {
 		ret = SWAP_FAIL;
 		goto out_unmap;
 	}
@@ -771,7 +836,7 @@ static int try_to_unmap_file(struct page *page, int migration)
 
 	list_for_each_entry(vma, &mapping->i_mmap_nonlinear,
 						shared.vm_set.list) {
-		if (vma->vm_flags & VM_LOCKED)
+		if ((vma->vm_flags & VM_LOCKED) && !migration)
 			continue;
 		cursor = (unsigned long) vma->vm_private_data;
 		if (cursor > max_nl_cursor)
@@ -805,7 +870,7 @@ static int try_to_unmap_file(struct page *page, int migration)
 	do {
 		list_for_each_entry(vma, &mapping->i_mmap_nonlinear,
 						shared.vm_set.list) {
-			if (vma->vm_flags & VM_LOCKED)
+			if ((vma->vm_flags & VM_LOCKED) && !migration)
 				continue;
 			cursor = (unsigned long) vma->vm_private_data;
 			while ( cursor < max_nl_cursor &&