1 files changed, 25 insertions, 0 deletions

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 7c6dfd2faa69..7cdac1676b59 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -805,6 +805,17 @@ static inline void *page_rmapping(struct page *page)
         return (void *)((unsigned long)page->mapping & ~PAGE_MAPPING_FLAGS);
 }
 
+extern struct address_space *__page_file_mapping(struct page *);
+
+static inline
+struct address_space *page_file_mapping(struct page *page)
+{
+        if (unlikely(PageSwapCache(page)))
+                return __page_file_mapping(page);
+
+        return page->mapping;
+}
+
 static inline int PageAnon(struct page *page)
 {
         return ((unsigned long)page->mapping & PAGE_MAPPING_ANON) != 0;
@@ -821,6 +832,20 @@ static inline pgoff_t page_index(struct page *page)
         return page->index;
 }
 
+extern pgoff_t __page_file_index(struct page *page);
+
+/*
+ * Return the file index of the page. Regular pagecache pages use ->index
+ * whereas swapcache pages use swp_offset(->private)
+ */
+static inline pgoff_t page_file_index(struct page *page)
+{
+        if (unlikely(PageSwapCache(page)))
+                return __page_file_index(page);
+
+        return page->index;
+}
+
 /*
  * Return true if this page is mapped into pagetables.
  */