batman-adv: add bat_neigh_free API

This API has to be used to let any routing protocol free
neighbor specific allocated resources
Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>

net/batman-adv/originator.c

@@ -197,13 +197,19 @@ static void batadv_neigh_node_free_rcu(struct rcu_head *rcu)
 	struct hlist_node *node_tmp;
 	struct batadv_neigh_node *neigh_node;
 	struct batadv_neigh_ifinfo *neigh_ifinfo;
+	struct batadv_algo_ops *bao;
 
 	neigh_node = container_of(rcu, struct batadv_neigh_node, rcu);
+	bao = neigh_node->orig_node->bat_priv->bat_algo_ops;
 
 	hlist_for_each_entry_safe(neigh_ifinfo, node_tmp,
 				  &neigh_node->ifinfo_list, list) {
 		batadv_neigh_ifinfo_free_ref_now(neigh_ifinfo);
 	}
+
+	if (bao->bat_neigh_free)
+		bao->bat_neigh_free(neigh_node);
+
 	batadv_hardif_free_ref_now(neigh_node->if_incoming);
 
 	kfree(neigh_node);

net/batman-adv/types.h

@@ -1121,6 +1121,8 @@ struct batadv_forw_packet {
  * @bat_neigh_is_equiv_or_better: check if neigh1 is equally good or better
  *  than neigh2 for their respective outgoing interface from the metric
  *  prospective
+ * @bat_neigh_free: free the resources allocated by the routing algorithm for a
+ *  neigh_node object
  * @bat_orig_print: print the originator table (optional)
  * @bat_orig_free: free the resources allocated by the routing algorithm for an
  *  orig_node object
@@ -1138,6 +1140,7 @@ struct batadv_algo_ops {
 	void (*bat_primary_iface_set)(struct batadv_hard_iface *hard_iface);
 	void (*bat_ogm_schedule)(struct batadv_hard_iface *hard_iface);
 	void (*bat_ogm_emit)(struct batadv_forw_packet *forw_packet);
+	/* neigh_node handling API */
 	int (*bat_neigh_cmp)(struct batadv_neigh_node *neigh1,
 			     struct batadv_hard_iface *if_outgoing1,
 			     struct batadv_neigh_node *neigh2,
@@ -1147,6 +1150,7 @@ struct batadv_algo_ops {
 		 struct batadv_hard_iface *if_outgoing1,
 		 struct batadv_neigh_node *neigh2,
 		 struct batadv_hard_iface *if_outgoing2);
+	void (*bat_neigh_free)(struct batadv_neigh_node *neigh);
 	/* orig_node handling API */
 	void (*bat_orig_print)(struct batadv_priv *priv, struct seq_file *seq,
 			       struct batadv_hard_iface *hard_iface);