Index: sys/compat/linuxkpi/common/include/linux/rwsem.h
===================================================================
--- sys/compat/linuxkpi/common/include/linux/rwsem.h
+++ sys/compat/linuxkpi/common/include/linux/rwsem.h
@@ -51,6 +51,7 @@
 #define	downgrade_write(_rw)		sx_downgrade(&(_rw)->sx)
 #define	down_read_nested(_rw, _sc)	down_read(_rw)
 #define	init_rwsem(_rw)			linux_init_rwsem(_rw, rwsem_name("lnxrwsem"))
+#define	down_write_nest_lock(sem, _rw)	down_write(_rw)
 
 #ifdef WITNESS_ALL
 /* NOTE: the maximum WITNESS name is 64 chars */