batman-adv: add list of unique single hop neighbors per hard-interface
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>
diff --git a/net/batman-adv/originator.c b/net/batman-adv/originator.c
index 7486df9..a8671c6 100644
--- a/net/batman-adv/originator.c
+++ b/net/batman-adv/originator.c
@@ -202,6 +202,47 @@
}
/**
+ * batadv_hardif_neigh_free_rcu - free the hardif neigh_node
+ * @rcu: rcu pointer of the neigh_node
+ */
+static void batadv_hardif_neigh_free_rcu(struct rcu_head *rcu)
+{
+ struct batadv_hardif_neigh_node *hardif_neigh;
+
+ hardif_neigh = container_of(rcu, struct batadv_hardif_neigh_node, rcu);
+
+ spin_lock_bh(&hardif_neigh->if_incoming->neigh_list_lock);
+ hlist_del_init_rcu(&hardif_neigh->list);
+ spin_unlock_bh(&hardif_neigh->if_incoming->neigh_list_lock);
+
+ batadv_hardif_free_ref_now(hardif_neigh->if_incoming);
+ kfree(hardif_neigh);
+}
+
+/**
+ * batadv_hardif_neigh_free_now - decrement the hardif neighbors refcounter
+ * and possibly free it (without rcu callback)
+ * @hardif_neigh: hardif neigh neighbor to free
+ */
+static void
+batadv_hardif_neigh_free_now(struct batadv_hardif_neigh_node *hardif_neigh)
+{
+ if (atomic_dec_and_test(&hardif_neigh->refcount))
+ batadv_hardif_neigh_free_rcu(&hardif_neigh->rcu);
+}
+
+/**
+ * batadv_hardif_neigh_free_ref - decrement the hardif neighbors refcounter
+ * and possibly free it
+ * @hardif_neigh: hardif neigh neighbor to free
+ */
+void batadv_hardif_neigh_free_ref(struct batadv_hardif_neigh_node *hardif_neigh)
+{
+ if (atomic_dec_and_test(&hardif_neigh->refcount))
+ call_rcu(&hardif_neigh->rcu, batadv_hardif_neigh_free_rcu);
+}
+
+/**
* batadv_neigh_node_free_rcu - free the neigh_node
* @rcu: rcu pointer of the neigh_node
*/
@@ -209,6 +250,7 @@
{
struct hlist_node *node_tmp;
struct batadv_neigh_node *neigh_node;
+ struct batadv_hardif_neigh_node *hardif_neigh;
struct batadv_neigh_ifinfo *neigh_ifinfo;
struct batadv_algo_ops *bao;
@@ -220,6 +262,14 @@
batadv_neigh_ifinfo_free_ref_now(neigh_ifinfo);
}
+ hardif_neigh = batadv_hardif_neigh_get(neigh_node->if_incoming,
+ neigh_node->addr);
+ if (hardif_neigh) {
+ /* batadv_hardif_neigh_get() increases refcount too */
+ batadv_hardif_neigh_free_now(hardif_neigh);
+ batadv_hardif_neigh_free_now(hardif_neigh);
+ }
+
if (bao->bat_neigh_free)
bao->bat_neigh_free(neigh_node);
@@ -479,6 +529,102 @@
}
/**
+ * batadv_hardif_neigh_create - create a hardif neighbour node
+ * @hard_iface: the interface this neighbour is connected to
+ * @neigh_addr: the interface address of the neighbour to retrieve
+ *
+ * Returns the hardif neighbour node if found or created or NULL otherwise.
+ */
+static struct batadv_hardif_neigh_node *
+batadv_hardif_neigh_create(struct batadv_hard_iface *hard_iface,
+ const u8 *neigh_addr)
+{
+ struct batadv_hardif_neigh_node *hardif_neigh = NULL;
+
+ spin_lock_bh(&hard_iface->neigh_list_lock);
+
+ /* check if neighbor hasn't been added in the meantime */
+ hardif_neigh = batadv_hardif_neigh_get(hard_iface, neigh_addr);
+ if (hardif_neigh)
+ goto out;
+
+ if (!atomic_inc_not_zero(&hard_iface->refcount))
+ goto out;
+
+ hardif_neigh = kzalloc(sizeof(*hardif_neigh), GFP_ATOMIC);
+ if (!hardif_neigh) {
+ batadv_hardif_free_ref(hard_iface);
+ goto out;
+ }
+
+ INIT_HLIST_NODE(&hardif_neigh->list);
+ ether_addr_copy(hardif_neigh->addr, neigh_addr);
+ hardif_neigh->if_incoming = hard_iface;
+ hardif_neigh->last_seen = jiffies;
+
+ atomic_set(&hardif_neigh->refcount, 1);
+
+ hlist_add_head(&hardif_neigh->list, &hard_iface->neigh_list);
+
+out:
+ spin_unlock_bh(&hard_iface->neigh_list_lock);
+ return hardif_neigh;
+}
+
+/**
+ * batadv_hardif_neigh_get_or_create - retrieve or create a hardif neighbour
+ * node
+ * @hard_iface: the interface this neighbour is connected to
+ * @neigh_addr: the interface address of the neighbour to retrieve
+ *
+ * Returns the hardif neighbour node if found or created or NULL otherwise.
+ */
+static struct batadv_hardif_neigh_node *
+batadv_hardif_neigh_get_or_create(struct batadv_hard_iface *hard_iface,
+ const u8 *neigh_addr)
+{
+ struct batadv_hardif_neigh_node *hardif_neigh = NULL;
+
+ /* first check without locking to avoid the overhead */
+ hardif_neigh = batadv_hardif_neigh_get(hard_iface, neigh_addr);
+ if (hardif_neigh)
+ return hardif_neigh;
+
+ return batadv_hardif_neigh_create(hard_iface, neigh_addr);
+}
+
+/**
+ * batadv_hardif_neigh_get - retrieve a hardif neighbour from the list
+ * @hard_iface: the interface where this neighbour is connected to
+ * @neigh_addr: the address of the neighbour
+ *
+ * Looks for and possibly returns a neighbour belonging to this hard interface.
+ * Returns NULL if the neighbour is not found.
+ */
+struct batadv_hardif_neigh_node *
+batadv_hardif_neigh_get(const struct batadv_hard_iface *hard_iface,
+ const u8 *neigh_addr)
+{
+ struct batadv_hardif_neigh_node *tmp_hardif_neigh, *hardif_neigh = NULL;
+
+ rcu_read_lock();
+ hlist_for_each_entry_rcu(tmp_hardif_neigh,
+ &hard_iface->neigh_list, list) {
+ if (!batadv_compare_eth(tmp_hardif_neigh->addr, neigh_addr))
+ continue;
+
+ if (!atomic_inc_not_zero(&tmp_hardif_neigh->refcount))
+ continue;
+
+ hardif_neigh = tmp_hardif_neigh;
+ break;
+ }
+ rcu_read_unlock();
+
+ return hardif_neigh;
+}
+
+/**
* batadv_neigh_node_new - create and init a new neigh_node object
* @orig_node: originator object representing the neighbour
* @hard_iface: the interface where the neighbour is connected to
@@ -493,11 +639,17 @@
const u8 *neigh_addr)
{
struct batadv_neigh_node *neigh_node;
+ struct batadv_hardif_neigh_node *hardif_neigh = NULL;
neigh_node = batadv_neigh_node_get(orig_node, hard_iface, neigh_addr);
if (neigh_node)
goto out;
+ hardif_neigh = batadv_hardif_neigh_get_or_create(hard_iface,
+ neigh_addr);
+ if (!hardif_neigh)
+ goto out;
+
neigh_node = kzalloc(sizeof(*neigh_node), GFP_ATOMIC);
if (!neigh_node)
goto out;
@@ -523,11 +675,16 @@
hlist_add_head_rcu(&neigh_node->list, &orig_node->neigh_list);
spin_unlock_bh(&orig_node->neigh_list_lock);
+ /* increment unique neighbor refcount */
+ atomic_inc(&hardif_neigh->refcount);
+
batadv_dbg(BATADV_DBG_BATMAN, orig_node->bat_priv,
"Creating new neighbor %pM for orig_node %pM on interface %s\n",
neigh_addr, orig_node->orig, hard_iface->net_dev->name);
out:
+ if (hardif_neigh)
+ batadv_hardif_neigh_free_ref(hardif_neigh);
return neigh_node;
}