batman-adv: split out router from orig_node

For the network wide multi interface optimization there are different
routers for each outgoing interface (outgoing from the OGM perspective,
incoming for payload traffic). To reflect this, change the router and
associated data to a list of routers.

While at it, rename batadv_orig_node_get_router() to
batadv_orig_router_get() to follow the new naming scheme.

Signed-off-by: Simon Wunderlich <simon@open-mesh.com>
Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch>
Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>

1 files changed, 234 insertions, 8 deletions

diff --git a/net/batman-adv/originator.c b/net/batman-adv/originator.c
index 1a4725f5267d..b8ef41600166 100644
--- a/net/batman-adv/originator.c
+++ b/net/batman-adv/originator.c
@@ -231,14 +231,31 @@ void batadv_neigh_node_free_ref(struct batadv_neigh_node *neigh_node)
 		call_rcu(&neigh_node->rcu, batadv_neigh_node_free_rcu);
 }
 
-/* increases the refcounter of a found router */
+/**
+ * batadv_orig_node_get_router - router to the originator depending on iface
+ * @orig_node: the orig node for the router
+ * @if_outgoing: the interface where the payload packet has been received or
+ *  the OGM should be sent to
+ *
+ * Returns the neighbor which should be router for this orig_node/iface.
+ *
+ * The object is returned with refcounter increased by 1.
+ */
 struct batadv_neigh_node *
-batadv_orig_node_get_router(struct batadv_orig_node *orig_node)
+batadv_orig_router_get(struct batadv_orig_node *orig_node,
+		       const struct batadv_hard_iface *if_outgoing)
 {
-	struct batadv_neigh_node *router;
+	struct batadv_orig_ifinfo *orig_ifinfo;
+	struct batadv_neigh_node *router = NULL;
 
 	rcu_read_lock();
-	router = rcu_dereference(orig_node->router);
+	hlist_for_each_entry_rcu(orig_ifinfo, &orig_node->ifinfo_list, list) {
+		if (orig_ifinfo->if_outgoing != if_outgoing)
+			continue;
+
+		router = rcu_dereference(orig_ifinfo->router);
+		break;
+	}
 
 	if (router && !atomic_inc_not_zero(&router->refcount))
 		router = NULL;
@@ -248,6 +265,86 @@ batadv_orig_node_get_router(struct batadv_orig_node *orig_node)
 }
 
 /**
+ * batadv_orig_ifinfo_get - find the ifinfo from an orig_node
+ * @orig_node: the orig node to be queried
+ * @if_outgoing: the interface for which the ifinfo should be acquired
+ *
+ * Returns the requested orig_ifinfo or NULL if not found.
+ *
+ * The object is returned with refcounter increased by 1.
+ */
+struct batadv_orig_ifinfo *
+batadv_orig_ifinfo_get(struct batadv_orig_node *orig_node,
+		       struct batadv_hard_iface *if_outgoing)
+{
+	struct batadv_orig_ifinfo *tmp, *orig_ifinfo = NULL;
+
+	rcu_read_lock();
+	hlist_for_each_entry_rcu(tmp, &orig_node->ifinfo_list,
+				 list) {
+		if (tmp->if_outgoing != if_outgoing)
+			continue;
+
+		if (!atomic_inc_not_zero(&tmp->refcount))
+			continue;
+
+		orig_ifinfo = tmp;
+		break;
+	}
+	rcu_read_unlock();
+
+	return orig_ifinfo;
+}
+
+/**
+ * batadv_orig_ifinfo_new - search and possibly create an orig_ifinfo object
+ * @orig_node: the orig node to be queried
+ * @if_outgoing: the interface for which the ifinfo should be acquired
+ *
+ * Returns NULL in case of failure or the orig_ifinfo object for the if_outgoing
+ * interface otherwise. The object is created and added to the list
+ * if it does not exist.
+ *
+ * The object is returned with refcounter increased by 1.
+ */
+struct batadv_orig_ifinfo *
+batadv_orig_ifinfo_new(struct batadv_orig_node *orig_node,
+		       struct batadv_hard_iface *if_outgoing)
+{
+	struct batadv_orig_ifinfo *orig_ifinfo = NULL;
+	unsigned long reset_time;
+
+	spin_lock_bh(&orig_node->neigh_list_lock);
+
+	orig_ifinfo = batadv_orig_ifinfo_get(orig_node, if_outgoing);
+	if (orig_ifinfo)
+		goto out;
+
+	orig_ifinfo = kzalloc(sizeof(*orig_ifinfo), GFP_ATOMIC);
+	if (!orig_ifinfo)
+		goto out;
+
+	if (if_outgoing != BATADV_IF_DEFAULT &&
+	    !atomic_inc_not_zero(&if_outgoing->refcount)) {
+		kfree(orig_ifinfo);
+		orig_ifinfo = NULL;
+		goto out;
+	}
+
+	reset_time = jiffies - 1;
+	reset_time -= msecs_to_jiffies(BATADV_RESET_PROTECTION_MS);
+	orig_ifinfo->batman_seqno_reset = reset_time;
+	orig_ifinfo->if_outgoing = if_outgoing;
+	INIT_HLIST_NODE(&orig_ifinfo->list);
+	atomic_set(&orig_ifinfo->refcount, 2);
+	hlist_add_head_rcu(&orig_ifinfo->list,
+			   &orig_node->ifinfo_list);
+out:
+	spin_unlock_bh(&orig_node->neigh_list_lock);
+	return orig_ifinfo;
+}
+
+/**
  * batadv_neigh_ifinfo_get - find the ifinfo from an neigh_node
  * @neigh_node: the neigh node to be queried
  * @if_outgoing: the interface for which the ifinfo should be acquired
@@ -360,11 +457,51 @@ out:
 	return neigh_node;
 }
 
+/**
+ * batadv_orig_ifinfo_free_rcu - free the orig_ifinfo object
+ * @rcu: rcu pointer of the orig_ifinfo object
+ */
+static void batadv_orig_ifinfo_free_rcu(struct rcu_head *rcu)
+{
+	struct batadv_orig_ifinfo *orig_ifinfo;
+
+	orig_ifinfo = container_of(rcu, struct batadv_orig_ifinfo, rcu);
+
+	if (orig_ifinfo->if_outgoing != BATADV_IF_DEFAULT)
+		batadv_hardif_free_ref_now(orig_ifinfo->if_outgoing);
+
+	kfree(orig_ifinfo);
+}
+
+/**
+ * batadv_orig_ifinfo_free_ref - decrement the refcounter and possibly free
+ *  the orig_ifinfo (without rcu callback)
+ * @orig_ifinfo: the orig_ifinfo object to release
+ */
+static void
+batadv_orig_ifinfo_free_ref_now(struct batadv_orig_ifinfo *orig_ifinfo)
+{
+	if (atomic_dec_and_test(&orig_ifinfo->refcount))
+		batadv_orig_ifinfo_free_rcu(&orig_ifinfo->rcu);
+}
+
+/**
+ * batadv_orig_ifinfo_free_ref - decrement the refcounter and possibly free
+ *  the orig_ifinfo
+ * @orig_ifinfo: the orig_ifinfo object to release
+ */
+void batadv_orig_ifinfo_free_ref(struct batadv_orig_ifinfo *orig_ifinfo)
+{
+	if (atomic_dec_and_test(&orig_ifinfo->refcount))
+		call_rcu(&orig_ifinfo->rcu, batadv_orig_ifinfo_free_rcu);
+}
+
 static void batadv_orig_node_free_rcu(struct rcu_head *rcu)
 {
 	struct hlist_node *node_tmp;
 	struct batadv_neigh_node *neigh_node;
 	struct batadv_orig_node *orig_node;
+	struct batadv_orig_ifinfo *orig_ifinfo;
 
 	orig_node = container_of(rcu, struct batadv_orig_node, rcu);
 
@@ -377,6 +514,11 @@ static void batadv_orig_node_free_rcu(struct rcu_head *rcu)
 		batadv_neigh_node_free_ref_now(neigh_node);
 	}
 
+	hlist_for_each_entry_safe(orig_ifinfo, node_tmp,
+				  &orig_node->ifinfo_list, list) {
+		hlist_del_rcu(&orig_ifinfo->list);
+		batadv_orig_ifinfo_free_ref_now(orig_ifinfo);
+	}
 	spin_unlock_bh(&orig_node->neigh_list_lock);
 
 	/* Free nc_nodes */
@@ -474,6 +616,7 @@ struct batadv_orig_node *batadv_orig_node_new(struct batadv_priv *bat_priv,
 
 	INIT_HLIST_HEAD(&orig_node->neigh_list);
 	INIT_LIST_HEAD(&orig_node->vlan_list);
+	INIT_HLIST_HEAD(&orig_node->ifinfo_list);
 	spin_lock_init(&orig_node->bcast_seqno_lock);
 	spin_lock_init(&orig_node->neigh_list_lock);
 	spin_lock_init(&orig_node->tt_buff_lock);
@@ -489,13 +632,11 @@ struct batadv_orig_node *batadv_orig_node_new(struct batadv_priv *bat_priv,
 	orig_node->bat_priv = bat_priv;
 	memcpy(orig_node->orig, addr, ETH_ALEN);
 	batadv_dat_init_orig_node_addr(orig_node);
-	orig_node->router = NULL;
 	atomic_set(&orig_node->last_ttvn, 0);
 	orig_node->tt_buff = NULL;
 	orig_node->tt_buff_len = 0;
 	reset_time = jiffies - 1 - msecs_to_jiffies(BATADV_RESET_PROTECTION_MS);
 	orig_node->bcast_seqno_reset = reset_time;
-	orig_node->batman_seqno_reset = reset_time;
 
 	/* create a vlan object for the "untagged" LAN */
 	vlan = batadv_orig_node_vlan_new(orig_node, BATADV_NO_FLAGS);
@@ -520,6 +661,55 @@ free_orig_node:
 }
 
 /**
+ * batadv_purge_orig_ifinfo - purge obsolete ifinfo entries from originator
+ * @bat_priv: the bat priv with all the soft interface information
+ * @orig_node: orig node which is to be checked
+ *
+ * Returns true if any ifinfo entry was purged, false otherwise.
+ */
+static bool
+batadv_purge_orig_ifinfo(struct batadv_priv *bat_priv,
+			 struct batadv_orig_node *orig_node)
+{
+	struct batadv_orig_ifinfo *orig_ifinfo;
+	struct batadv_hard_iface *if_outgoing;
+	struct hlist_node *node_tmp;
+	bool ifinfo_purged = false;
+
+	spin_lock_bh(&orig_node->neigh_list_lock);
+
+	/* for all ifinfo objects for this originator */
+	hlist_for_each_entry_safe(orig_ifinfo, node_tmp,
+				  &orig_node->ifinfo_list, list) {
+		if_outgoing = orig_ifinfo->if_outgoing;
+
+		/* always keep the default interface */
+		if (if_outgoing == BATADV_IF_DEFAULT)
+			continue;
+
+		/* don't purge if the interface is not (going) down */
+		if ((if_outgoing->if_status != BATADV_IF_INACTIVE) &&
+		    (if_outgoing->if_status != BATADV_IF_NOT_IN_USE) &&
+		    (if_outgoing->if_status != BATADV_IF_TO_BE_REMOVED))
+			continue;
+
+		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
+			   "router/ifinfo purge: originator %pM, iface: %s\n",
+			   orig_node->orig, if_outgoing->net_dev->name);
+
+		ifinfo_purged = true;
+
+		hlist_del_rcu(&orig_ifinfo->list);
+		batadv_orig_ifinfo_free_ref(orig_ifinfo);
+	}
+
+	spin_unlock_bh(&orig_node->neigh_list_lock);
+
+	return ifinfo_purged;
+}
+
+
+/**
  * batadv_purge_orig_neighbors - purges neighbors from originator
  * @bat_priv: the bat priv with all the soft interface information
  * @orig_node: orig node which is to be checked
@@ -607,10 +797,22 @@ batadv_find_best_neighbor(struct batadv_priv *bat_priv,
 	return best;
 }
 
+/**
+ * batadv_purge_orig_node - purges obsolete information from an orig_node
+ * @bat_priv: the bat priv with all the soft interface information
+ * @orig_node: orig node which is to be checked
+ *
+ * This function checks if the orig_node or substructures of it have become
+ * obsolete, and purges this information if that's the case.
+ *
+ * Returns true if the orig_node is to be removed, false otherwise.
+ */
 static bool batadv_purge_orig_node(struct batadv_priv *bat_priv,
 				   struct batadv_orig_node *orig_node)
 {
 	struct batadv_neigh_node *best_neigh_node;
+	struct batadv_hard_iface *hard_iface;
+	bool changed;
 
 	if (batadv_has_timed_out(orig_node->last_seen,
 				 2 * BATADV_PURGE_TIMEOUT)) {
@@ -620,15 +822,39 @@ static bool batadv_purge_orig_node(struct batadv_priv *bat_priv,
 			   jiffies_to_msecs(orig_node->last_seen));
 		return true;
 	}
-	if (!batadv_purge_orig_neighbors(bat_priv, orig_node))
+	changed = batadv_purge_orig_ifinfo(bat_priv, orig_node);
+	changed = changed || batadv_purge_orig_neighbors(bat_priv, orig_node);
+
+	if (!changed)
 		return false;
 
+	/* first for NULL ... */
 	best_neigh_node = batadv_find_best_neighbor(bat_priv, orig_node,
 						    BATADV_IF_DEFAULT);
-	batadv_update_route(bat_priv, orig_node, best_neigh_node);
+	batadv_update_route(bat_priv, orig_node, BATADV_IF_DEFAULT,
+			    best_neigh_node);
 	if (best_neigh_node)
 		batadv_neigh_node_free_ref(best_neigh_node);
 
+	/* ... then for all other interfaces. */
+	rcu_read_lock();
+	list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
+		if (hard_iface->if_status != BATADV_IF_ACTIVE)
+			continue;
+
+		if (hard_iface->soft_iface != bat_priv->soft_iface)
+			continue;
+
+		best_neigh_node = batadv_find_best_neighbor(bat_priv,
+							    orig_node,
+							    hard_iface);
+		batadv_update_route(bat_priv, orig_node, hard_iface,
+				    best_neigh_node);
+		if (best_neigh_node)
+			batadv_neigh_node_free_ref(best_neigh_node);
+	}
+	rcu_read_unlock();
+
 	return false;
 }