integrity: mtime patch for mmap files

Index: linux-2.6.21-rc3-mm2/fs/inode.c
===================================================================
@@ -1209,8 +1209,8 @@ void touch_atime(struct vfsmount *mnt, s
 EXPORT_SYMBOL(touch_atime);
 
 /**
- *	file_update_time	-	update mtime and ctime time
- *	@file: file accessed
+ *	inode_update_time	-	update mtime and ctime time
+ *	@inode: file accessed
  *
  *	Update the mtime and ctime members of an inode and mark the inode
  *	for writeback.  Note that this function is meant exclusively for

@@ -1220,9 +1220,8 @@ EXPORT_SYMBOL(touch_atime);
  *	timestamps are handled by the server.
  */
 
-void file_update_time(struct file *file)
+void inode_update_time(struct inode *inode)
 {
-	struct inode *inode = file->f_path.dentry->d_inode;
 	struct timespec now;
 	int sync_it = 0;
 

@@ -1246,7 +1245,7 @@ void file_update_time(struct file *file)
 		mark_inode_dirty_sync(inode);
 }
 
-EXPORT_SYMBOL(file_update_time);
+EXPORT_SYMBOL(inode_update_time);
 
 int inode_needs_sync(struct inode *inode)
 {

Index: linux-2.6.21-rc3-mm2/fs/fs-writeback.c
===================================================================
@@ -167,6 +167,9 @@ __sync_single_inode(struct inode *inode,
 
 	spin_unlock(&inode_lock);
 
+	if (test_and_clear_bit(AS_MCTIME, &mapping->flags))
+		inode_update_time(inode);
+
 	ret = do_writepages(mapping, wbc);
 
 	/* Don't write the inode if only I_DIRTY_PAGES was set */

Index: linux-2.6.21-rc3-mm2/fs/buffer.c
===================================================================
@@ -734,8 +734,11 @@ int __set_page_dirty_buffers(struct page
 	}
 	spin_unlock(&mapping->private_lock);
 
-	if (TestSetPageDirty(page))
+	if (TestSetPageDirty(page)) {
+		if (page_mapped(page))
+			set_bit(AS_MCTIME, &mapping->flags);
 		return 0;
+	}
 
 	write_lock_irq(&mapping->tree_lock);
 	if (page->mapping) {	/* Race with truncate? */

@@ -749,6 +752,8 @@ int __set_page_dirty_buffers(struct page
 	}
 	write_unlock_irq(&mapping->tree_lock);
 	__mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
+	if (page_mapped(page))
+		set_bit(AS_MCTIME, &mapping->flags);
 	return 1;
 }
 EXPORT_SYMBOL(__set_page_dirty_buffers);

Index: linux-2.6.21-rc3-mm2/include/linux/fs.h
===================================================================
@@ -1944,7 +1944,12 @@ extern int buffer_migrate_page(struct ad
 extern int inode_change_ok(struct inode *, struct iattr *);
 extern int __must_check inode_setattr(struct inode *, struct iattr *);
 
-extern void file_update_time(struct file *file);
+extern void inode_update_time(struct inode *);
+
+static inline void file_update_time(struct file *file)
+{
+	inode_update_time(file->f_dentry->d_inode);
+}
 
 static inline ino_t parent_ino(struct dentry *dentry)
 {

Index: linux-2.6.21-rc3-mm2/include/linux/pagemap.h
===================================================================
@@ -17,8 +17,9 @@
  * Bits in mapping->flags.  The lower __GFP_BITS_SHIFT bits are the page
  * allocation mode flags.
  */
-#define	AS_EIO		(__GFP_BITS_SHIFT + 0)	/* IO error on async write */
+#define AS_EIO		(__GFP_BITS_SHIFT + 0)	/* IO error on async write */
 #define AS_ENOSPC	(__GFP_BITS_SHIFT + 1)	/* ENOSPC on async write */
+#define AS_MCTIME	(__GFP_BITS_SHIFT + 2)	/* need m/ctime change */
 
 static inline void mapping_set_error(struct address_space *mapping, int error)
 {

Index: linux-2.6.21-rc3-mm2/mm/page-writeback.c
===================================================================
@@ -815,8 +815,10 @@ int __set_page_dirty_no_writeback(struct
  */
 int __set_page_dirty_nobuffers(struct page *page)
 {
+	struct address_space *mapping = page_mapping(page);
+	int ret = 0;
+
 	if (!TestSetPageDirty(page)) {
-		struct address_space *mapping = page_mapping(page);
 		struct address_space *mapping2;
 
 		if (!mapping)

@@ -840,9 +842,11 @@ int __set_page_dirty_nobuffers(struct pa
 			/* !PageAnon && !swapper_space */
 			__mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
 		}
-		return 1;
+		ret = 1;
 	}
-	return 0;
+	if (page_mapped(page))
+		set_bit(AS_MCTIME, &mapping->flags);
+	return ret;
 }
 EXPORT_SYMBOL(__set_page_dirty_nobuffers);