1 files changed, 13 insertions, 4 deletions

diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h
index 01ca0856caf..34da5230faa 100644
--- a/include/linux/pagemap.h
+++ b/include/linux/pagemap.h
@@ -18,9 +18,14 @@
  * 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_ENOSPC       (__GFP_BITS_SHIFT + 1)  /* ENOSPC on async write */
-#define AS_MM_ALL_LOCKS (__GFP_BITS_SHIFT + 2)  /* under mm_take_all_locks() */
+enum mapping_flags {
+        AS_EIO          = __GFP_BITS_SHIFT + 0, /* IO error on async write */
+        AS_ENOSPC       = __GFP_BITS_SHIFT + 1, /* ENOSPC on async write */
+        AS_MM_ALL_LOCKS = __GFP_BITS_SHIFT + 2, /* under mm_take_all_locks() */
+#ifdef CONFIG_UNEVICTABLE_LRU
+        AS_UNEVICTABLE  = __GFP_BITS_SHIFT + 3, /* e.g., ramdisk, SHM_LOCK */
+#endif
+};
 
 static inline void mapping_set_error(struct address_space *mapping, int error)
 {
@@ -33,7 +38,6 @@ static inline void mapping_set_error(struct address_space *mapping, int error)
 }
 
 #ifdef CONFIG_UNEVICTABLE_LRU
-#define AS_UNEVICTABLE  (__GFP_BITS_SHIFT + 2)  /* e.g., ramdisk, SHM_LOCK */
 
 static inline void mapping_set_unevictable(struct address_space *mapping)
 {
@@ -380,6 +384,11 @@ static inline void wait_on_page_writeback(struct page *page)
 extern void end_page_writeback(struct page *page);
 
 /*
+ * Add an arbitrary waiter to a page's wait queue
+ */
+extern void add_page_wait_queue(struct page *page, wait_queue_t *waiter);
+
+/*
  * Fault a userspace page into pagetables.  Return non-zero on a fault.
  *
  * This assumes that two userspace pages are always sufficient.  That's