diff --git a/include/xilinx.h b/include/xilinx.h
index d0799bc..2cb2e5b 100644
--- a/include/xilinx.h
+++ b/include/xilinx.h
@@ -100,5 +100,6 @@
 typedef int (*Xilinx_abort_fn)( int cookie );
 typedef int (*Xilinx_pre_fn)( int cookie );
 typedef int (*Xilinx_post_fn)( int cookie );
+typedef int (*Xilinx_bwr_fn)( void *buf, size_t len, int flush, int cookie );
 
 #endif  /* _XILINX_H_ */