path: root/net/batman-adv/routing.c

/*
 * Copyright (C) 2007-2012 B.A.T.M.A.N. contributors:
 *
 * Marek Lindner, Simon Wunderlich
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of version 2 of the GNU General Public
 * License as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301, USA
 *
 */

#include "main.h"
#include "routing.h"
#include "send.h"
#include "soft-interface.h"
#include "hard-interface.h"
#include "icmp_socket.h"
#include "translation-table.h"
#include "originator.h"
#include "vis.h"
#include "unicast.h"

void slide_own_bcast_window(struct hard_iface *hard_iface)
{
	struct bat_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
	struct hashtable_t *hash = bat_priv->orig_hash;
	struct hlist_node *node;
	struct hlist_head *head;
	struct orig_node *orig_node;
	unsigned long *word;
	uint32_t i;
	size_t word_index;

	for (i = 0; i < hash->size; i++) {
		head = &hash->table[i];

		rcu_read_lock();
		hlist_for_each_entry_rcu(orig_node, node, head, hash_entry) {
			spin_lock_bh(&orig_node->ogm_cnt_lock);
			word_index = hard_iface->if_num * NUM_WORDS;
			word = &(orig_node->bcast_own[word_index]);

			bit_get_packet(bat_priv, word, 1, 0);
			orig_node->bcast_own_sum[hard_iface->if_num] =
				bit_packet_count(word);
			spin_unlock_bh(&orig_node->ogm_cnt_lock);
		}
		rcu_read_unlock();
	}
}

static void _update_route(struct bat_priv *bat_priv,
			  struct orig_node *orig_node,
			  struct neigh_node *neigh_node)
{
	struct neigh_node *curr_router;

	curr_router = orig_node_get_router(orig_node);

	/* route deleted */
	if ((curr_router) && (!neigh_node)) {
		bat_dbg(DBG_ROUTES, bat_priv, "Deleting route towards: %pM\n",
			orig_node->orig);
		tt_global_del_orig(bat_priv, orig_node,
				   "Deleted route towards originator");

	/* route added */
	} else if ((!curr_router) && (neigh_node)) {

		bat_dbg(DBG_ROUTES, bat_priv,
			"Adding route towards: %pM (via %pM)\n",
			orig_node->orig, neigh_node->addr);
	/* route changed */
	} else if (neigh_node && curr_router) {
		bat_dbg(DBG_ROUTES, bat_priv,
			"Changing route towards: %pM "
			"(now via %pM - was via %pM)\n",
			orig_node->orig, neigh_node->addr,
			curr_router->addr);
	}

	if (curr_router)
		neigh_node_free_ref(curr_router);

	/* increase refcount of new best neighbor */
	if (neigh_node && !atomic_inc_not_zero(&neigh_node->refcount))
		neigh_node = NULL;

	spin_lock_bh(&orig_node->neigh_list_lock);
	rcu_assign_pointer(orig_node->router, neigh_node);
	spin_unlock_bh(&orig_node->neigh_list_lock);

	/* decrease refcount of previous best neighbor */
	if (curr_router)
		neigh_node_free_ref(curr_router);
}

void update_route(struct bat_priv *bat_priv, struct orig_node *orig_node,
		  struct neigh_node *neigh_node)
{
	struct neigh_node *router = NULL;

	if (!orig_node)
		goto out;

	router = orig_node_get_router(orig_node);

	if (router != neigh_node)
		_update_route(bat_priv, orig_node, neigh_node);

out:
	if (router)
		neigh_node_free_ref(router);
}

/* caller must hold the neigh_list_lock */
void