cdev_ioctl
error = cdev_ioctl(dev, cmd, data, flag, l);
return cdev_ioctl(vp->v_rdev, ap->a_command,
error = cdev_ioctl(devctty, ap->a_command, ap->a_data,
ioctl = cdev_ioctl;
error = cdev_ioctl(dev, ap->a_command, ap->a_data,
dev_type_ioctl(cdev_ioctl);