+static void *res_tracker_lookup(struct rb_root *root, u64 res_id)
+{
+ struct rb_node *node = root->rb_node;
+
+ while (node) {
+ struct res_common *res = container_of(node, struct res_common,
+ node);
+
+ if (res_id < res->res_id)
+ node = node->rb_left;
+ else if (res_id > res->res_id)
+ node = node->rb_right;
+ else
+ return res;
+ }
+ return NULL;
+}
+
+static int res_tracker_insert(struct rb_root *root, struct res_common *res)
+{
+ struct rb_node **new = &(root->rb_node), *parent = NULL;
+
+ /* Figure out where to put new node */
+ while (*new) {
+ struct res_common *this = container_of(*new, struct res_common,
+ node);
+
+ parent = *new;
+ if (res->res_id < this->res_id)
+ new = &((*new)->rb_left);
+ else if (res->res_id > this->res_id)
+ new = &((*new)->rb_right);
+ else
+ return -EEXIST;
+ }
+
+ /* Add new node and rebalance tree. */
+ rb_link_node(&res->node, parent, new);
+ rb_insert_color(&res->node, root);
+
+ return 0;
+}
+