diff --git a/swaponoff.c b/swaponoff.c
index eda1510..d792c70 100644
--- a/swaponoff.c
+++ b/swaponoff.c
@@ -24,10 +24,13 @@
 
 #include "busybox.h"
 #include <stdio.h>
-#include <sys/mount.h>
 #include <mntent.h>
 #include <dirent.h>
 #include <errno.h>
+#include <stdlib.h>
+#include <sys/mount.h>
+#include <sys/syscall.h>
+#include <linux/unistd.h>
 
 _syscall2(int, swapon, const char *, path, int, flags);
 _syscall1(int, swapoff, const char *, path);