diff --git a/original/linux/ion.h b/original/linux/ion.h
index e72c09e..a7d399c 100644
--- a/original/linux/ion.h
+++ b/original/linux/ion.h
@@ -52,6 +52,9 @@
 					   cached, ion will do cache
 					   maintenance when the buffer is
 					   mapped for dma */
+#define ION_FLAG_CACHED_NEEDS_SYNC 2	/* mappings of this buffer will created
+					   at mmap time, if this is set
+					   caches must be managed manually */
 
 #ifdef __KERNEL__
 struct ion_device;