diff --git a/sys/cam/ctl/ctl_io.h b/sys/cam/ctl/ctl_io.h
index 60f8aef82d02..349cb02820d9 100644
--- a/sys/cam/ctl/ctl_io.h
+++ b/sys/cam/ctl/ctl_io.h
@@ -42,6 +42,10 @@
 #ifndef	_CTL_IO_H_
 #define	_CTL_IO_H_
 
+#ifndef _KERNEL
+#include <stdbool.h>
+#endif
+
 #define	CTL_MAX_CDBLEN	32
 /*
  * Uncomment this next line to enable printing out times for I/Os