diff --git a/sys/fs/nwfs/nwfs_subr.c b/sys/fs/nwfs/nwfs_subr.c
index 3d7734280e3c..ad6009c825b7 100644
--- a/sys/fs/nwfs/nwfs_subr.c
+++ b/sys/fs/nwfs/nwfs_subr.c
@@ -34,6 +34,7 @@
 #include <sys/param.h>
 #include <sys/systm.h>
 #include <sys/kernel.h>
+#include <sys/lockmgr.h>
 #include <sys/malloc.h>
 #include <machine/clock.h>
 #include <sys/time.h>