1 files changed, 8 insertions, 0 deletions

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 84bb449b9b01..e059da947007 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -363,6 +363,8 @@ struct address_space_operations {
                         loff_t offset, unsigned long nr_segs);
         struct page* (*get_xip_page)(struct address_space *, sector_t,
                         int);
+        /* migrate the contents of a page to the specified target */
+        int (*migratepage) (struct page *, struct page *);
 };
 
 struct backing_dev_info;
@@ -1719,6 +1721,12 @@ extern void simple_release_fs(struct vfsmount **mount, int *count);
 
 extern ssize_t simple_read_from_buffer(void __user *, size_t, loff_t *, const void *, size_t);
 
+#ifdef CONFIG_MIGRATION
+extern int buffer_migrate_page(struct page *, struct page *);
+#else
+#define buffer_migrate_page NULL
+#endif
+
 extern int inode_change_ok(struct inode *, struct iattr *);
 extern int __must_check inode_setattr(struct inode *, struct iattr *);