static int is_client_alive(struct ion_client *client)
{
	struct rb_node *node;
	struct ion_client *tmp;
	struct ion_device *dev;

	node = ion_root_client->rb_node;
	dev = container_of(ion_root_client, struct ion_device, clients);

	down_read(&dev->lock);
	while (node) {
		tmp = rb_entry(node, struct ion_client, node);
		if (client < tmp) {
			node = node->rb_left;
		} else if (client > tmp) {
			node = node->rb_right;
		} else {
			up_read(&dev->lock);
			return 1;
		}
	}

	up_read(&dev->lock);
	return 0;
}
static int is_client_alive(struct ion_client *client)
{
	struct rb_node *node;
	struct ion_client *tmp;
	struct ion_device *dev;

	node = ion_root_client->rb_node;
	dev = container_of(ion_root_client, struct ion_device, clients);

	down_read(&dev->lock);
	while (node) {
		tmp = rb_entry(node, struct ion_client, node);
		if (client < tmp) {
			node = node->rb_left;
		} else if (client > tmp) {
			node = node->rb_right;
		} else {
			up_read(&dev->lock);
			return 1;
		}
	}

	up_read(&dev->lock);
	return 0;
}