struct data {
	...
	struct kref ref;
	...
};

kref_init(&data->kref);
kref_get(&data->kref);
kref_put(&data->kref, data_release);

void data_release(struct kref *ref)
{
	struct data *data = container_of(ref, struct data, ref);
	kfree(data);
}


TODO: kobject e kset