1 files changed, 7 insertions, 0 deletions

diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt
index 55c28b79d8dc..20899e095e7e 100644
--- a/Documentation/filesystems/vfs.txt
+++ b/Documentation/filesystems/vfs.txt
@@ -534,6 +534,7 @@ struct address_space_operations {
         sector_t (*bmap)(struct address_space *, sector_t);
         int (*invalidatepage) (struct page *, unsigned long);
         int (*releasepage) (struct page *, int);
+        void (*freepage)(struct page *);
         ssize_t (*direct_IO)(int, struct kiocb *, const struct iovec *iov,
                         loff_t offset, unsigned long nr_segs);
         struct page* (*get_xip_page)(struct address_space *, sector_t,
@@ -678,6 +679,12 @@ struct address_space_operations {
         need to ensure this.  Possibly it can clear the PageUptodate
         bit if it cannot free private data yet.
 
+  freepage: freepage is called once the page is no longer visible in
+        the page cache in order to allow the cleanup of any private
+        data. Since it may be called by the memory reclaimer, it
+        should not assume that the original address_space mapping still
+        exists, and it should not block.
+
   direct_IO: called by the generic read/write routines to perform
         direct_IO - that is IO requests which bypass the page cache
         and transfer data directly between the storage and the