diff --git a/sys/boot/kshim/bsd_kernel.h b/sys/boot/kshim/bsd_kernel.h
index efae6c41472a..6645c6277a81 100644
--- a/sys/boot/kshim/bsd_kernel.h
+++ b/sys/boot/kshim/bsd_kernel.h
@@ -35,6 +35,8 @@
 #include <sys/queue.h>
 #include <sys/errno.h>
 
+#define	howmany(x, y)	(((x)+((y)-1))/(y))
+#define	nitems(x)	(sizeof((x)) / sizeof((x)[0]))
 #define	isalpha(x) (((x) >= 'a' && (x) <= 'z') || ((x) >= 'A' && (x) <= 'Z'))
 #define	isdigit(x) ((x) >= '0' && (x) <= '9')
 #define	panic(...) do { printf("USB PANIC: " __VA_ARGS__); while (1) ; } while (0)