+struct address_space *page_mapping(struct page *page)
+{
+ struct address_space *mapping = page->mapping;
+
+ VM_BUG_ON(PageSlab(page));
+#ifdef CONFIG_SWAP
+ if (unlikely(PageSwapCache(page))) {
+ swp_entry_t entry;
+
+ entry.val = page_private(page);
+ mapping = swap_address_space(entry);
+ } else
+#endif
+ if ((unsigned long)mapping & PAGE_MAPPING_ANON)
+ mapping = NULL;
+ return mapping;
+}
+