diff --git a/include/linux/auto_dev-ioctl.h b/include/linux/auto_dev-ioctl.h
index 7caaf298f539..bf82e3a758e5 100644
--- a/include/linux/auto_dev-ioctl.h
+++ b/include/linux/auto_dev-ioctl.h
@@ -18,8 +18,6 @@
 #define AUTOFS_DEV_IOCTL_VERSION_MAJOR	1
 #define AUTOFS_DEV_IOCTL_VERSION_MINOR	0
 
-#define AUTOFS_DEVID_LEN		16
-
 #define AUTOFS_DEV_IOCTL_SIZE		sizeof(struct autofs_dev_ioctl)
 
 /*