linux/net/batman-adv/main.c
Antonio Quartulli cc47f66e6b batman-adv: improved roaming mechanism
With the current client announcement implementation, in case of roaming,
an update is triggered on the new AP serving the client. At that point
the new information is spread around by means of the OGM broadcasting
mechanism. Until this operations is not executed, no node is able to
correctly route traffic towards the client. This obviously causes packet
drops and introduces a delay in the time needed by the client to recover
its connections.

A new packet type called ROAMING_ADVERTISEMENT is added to account this
issue.

This message is sent in case of roaming from the new AP serving the
client to the old one and will contain the client MAC address. In this
way an out-of-OGM update is immediately committed, so that the old node
can update its global translation table. Traffic reaching this node will
then be redirected to the correct destination utilising the fresher
information. Thus reducing the packet drops and the connection recovery
delay.

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
2011-06-20 11:37:27 +02:00

193 lines
4.6 KiB
C

/*
* Copyright (C) 2007-2011 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 "bat_sysfs.h"
#include "bat_debugfs.h"
#include "routing.h"
#include "send.h"
#include "originator.h"
#include "soft-interface.h"
#include "icmp_socket.h"
#include "translation-table.h"
#include "hard-interface.h"
#include "gateway_client.h"
#include "vis.h"
#include "hash.h"
/* List manipulations on hardif_list have to be rtnl_lock()'ed,
* list traversals just rcu-locked */
struct list_head hardif_list;
unsigned char broadcast_addr[] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
struct workqueue_struct *bat_event_workqueue;
static int __init batman_init(void)
{
INIT_LIST_HEAD(&hardif_list);
/* the name should not be longer than 10 chars - see
* http://lwn.net/Articles/23634/ */
bat_event_workqueue = create_singlethread_workqueue("bat_events");
if (!bat_event_workqueue)
return -ENOMEM;
bat_socket_init();
debugfs_init();
register_netdevice_notifier(&hard_if_notifier);
pr_info("B.A.T.M.A.N. advanced %s%s (compatibility version %i) "
"loaded\n", SOURCE_VERSION, REVISION_VERSION_STR,
COMPAT_VERSION);
return 0;
}
static void __exit batman_exit(void)
{
debugfs_destroy();
unregister_netdevice_notifier(&hard_if_notifier);
hardif_remove_interfaces();
flush_workqueue(bat_event_workqueue);
destroy_workqueue(bat_event_workqueue);
bat_event_workqueue = NULL;
rcu_barrier();
}
int mesh_init(struct net_device *soft_iface)
{
struct bat_priv *bat_priv = netdev_priv(soft_iface);
spin_lock_init(&bat_priv->forw_bat_list_lock);
spin_lock_init(&bat_priv->forw_bcast_list_lock);
spin_lock_init(&bat_priv->tt_lhash_lock);
spin_lock_init(&bat_priv->tt_ghash_lock);
spin_lock_init(&bat_priv->tt_changes_list_lock);
spin_lock_init(&bat_priv->tt_req_list_lock);
spin_lock_init(&bat_priv->tt_roam_list_lock);
spin_lock_init(&bat_priv->tt_buff_lock);
spin_lock_init(&bat_priv->gw_list_lock);
spin_lock_init(&bat_priv->vis_hash_lock);
spin_lock_init(&bat_priv->vis_list_lock);
spin_lock_init(&bat_priv->softif_neigh_lock);
spin_lock_init(&bat_priv->softif_neigh_vid_lock);
INIT_HLIST_HEAD(&bat_priv->forw_bat_list);
INIT_HLIST_HEAD(&bat_priv->forw_bcast_list);
INIT_HLIST_HEAD(&bat_priv->gw_list);
INIT_HLIST_HEAD(&bat_priv->softif_neigh_vids);
INIT_LIST_HEAD(&bat_priv->tt_changes_list);
INIT_LIST_HEAD(&bat_priv->tt_req_list);
INIT_LIST_HEAD(&bat_priv->tt_roam_list);
if (originator_init(bat_priv) < 1)
goto err;
if (tt_init(bat_priv) < 1)
goto err;
tt_local_add(soft_iface, soft_iface->dev_addr);
if (vis_init(bat_priv) < 1)
goto err;
atomic_set(&bat_priv->mesh_state, MESH_ACTIVE);
goto end;
err:
pr_err("Unable to allocate memory for mesh information structures: "
"out of mem ?\n");
mesh_free(soft_iface);
return -1;
end:
return 0;
}
void mesh_free(struct net_device *soft_iface)
{
struct bat_priv *bat_priv = netdev_priv(soft_iface);
atomic_set(&bat_priv->mesh_state, MESH_DEACTIVATING);
purge_outstanding_packets(bat_priv, NULL);
vis_quit(bat_priv);
gw_node_purge(bat_priv);
originator_free(bat_priv);
tt_free(bat_priv);
softif_neigh_purge(bat_priv);
atomic_set(&bat_priv->mesh_state, MESH_INACTIVE);
}
void inc_module_count(void)
{
try_module_get(THIS_MODULE);
}
void dec_module_count(void)
{
module_put(THIS_MODULE);
}
int is_my_mac(const uint8_t *addr)
{
const struct hard_iface *hard_iface;
rcu_read_lock();
list_for_each_entry_rcu(hard_iface, &hardif_list, list) {
if (hard_iface->if_status != IF_ACTIVE)
continue;
if (compare_eth(hard_iface->net_dev->dev_addr, addr)) {
rcu_read_unlock();
return 1;
}
}
rcu_read_unlock();
return 0;
}
module_init(batman_init);
module_exit(batman_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_SUPPORTED_DEVICE(DRIVER_DEVICE);
#ifdef REVISION_VERSION
MODULE_VERSION(SOURCE_VERSION "-" REVISION_VERSION);
#else
MODULE_VERSION(SOURCE_VERSION);
#endif