-int cdevsw_add(int, struct cdevsw *);
-int cdevsw_add_with_bdev(int index, struct cdevsw * csw, int bdev);
-int cdevsw_remove(int, struct cdevsw *);
+int cdevsw_add(int, const struct cdevsw *);
+int cdevsw_add_with_bdev(int index, const struct cdevsw * csw, int bdev);
+int cdevsw_remove(int, const struct cdevsw *);