+static struct o2hb_region *o2hb_find_region(const char *region_uuid)
+{
+ struct o2hb_region *p, *reg = NULL;
+
+ assert_spin_locked(&o2hb_live_lock);
+
+ list_for_each_entry(p, &o2hb_all_regions, hr_all_item) {
+ if (!strcmp(region_uuid, config_item_name(&p->hr_item))) {
+ reg = p;
+ break;
+ }
+ }
+
+ return reg;
+}
+
+static int o2hb_region_get(const char *region_uuid)
+{
+ int ret = 0;
+ struct o2hb_region *reg;
+
+ spin_lock(&o2hb_live_lock);
+
+ reg = o2hb_find_region(region_uuid);
+ if (!reg)
+ ret = -ENOENT;
+ spin_unlock(&o2hb_live_lock);
+
+ if (ret)
+ goto out;
+
+ ret = o2nm_depend_this_node();
+ if (ret)
+ goto out;
+
+ ret = o2nm_depend_item(®->hr_item);
+ if (ret)
+ o2nm_undepend_this_node();
+
+out:
+ return ret;
+}
+
+static void o2hb_region_put(const char *region_uuid)
+{
+ struct o2hb_region *reg;
+
+ spin_lock(&o2hb_live_lock);
+
+ reg = o2hb_find_region(region_uuid);
+
+ spin_unlock(&o2hb_live_lock);
+
+ if (reg) {
+ o2nm_undepend_item(®->hr_item);
+ o2nm_undepend_this_node();
+ }
+}
+
+int o2hb_register_callback(const char *region_uuid,
+ struct o2hb_callback_func *hc)