int can_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg);
int can_ioctl_query(struct canuser_t *canuser, unsigned long what);
int can_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg);
int can_ioctl_query(struct canuser_t *canuser, unsigned long what);