+#define pfn_to_page(pfn) \
+({ \
+ unsigned long kaddr = (unsigned long)__va((pfn) << PAGE_SHIFT); \
+ (NODE_DATA(kvaddr_to_nid(kaddr))->node_mem_map + local_mapnr(kaddr)); \
+})
+
+#define page_to_pfn(page) \
+ ((page) - page_zone(page)->zone_mem_map + \
+ (page_zone(page)->zone_start_pfn))
+