Index: arch/amd64/include/types.h
===================================================================
--- arch/amd64/include/types.h	(revision fa2d38295826e03b7d6e05160b05886ceb03f652)
+++ arch/amd64/include/types.h	(revision bb68433fea16aec0b0b4240149c9c3e8fb347b34)
@@ -40,4 +40,5 @@
 
 typedef __u64 __address;
+typedef __u64 pfn_t;
 
 /* Flags of processor (return value of interrupts_disable()) */