linux-sg2042/net/batman-adv/bat_v_elp.c

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batman-adv: ELP - adding basic infrastructure The B.A.T.M.A.N. protocol originally only used a single message type (called OGM) to determine the link qualities to the direct neighbors and spreading these link quality information through the whole mesh. This procedure is summarized on the BATMAN concept page and explained in details in the RFC draft published in 2008. This approach was chosen for its simplicity during the protocol design phase and the implementation. However, it also bears some drawbacks: * Wireless interfaces usually come with some packet loss, therefore a higher broadcast rate is desirable to allow a fast reaction on flaky connections. Other interfaces of the same host might be connected to Ethernet LANs / VPNs / etc which rarely exhibit packet loss would benefit from a lower broadcast rate to reduce overhead. * It generally is more desirable to detect local link quality changes at a faster rate than propagating all these changes through the entire mesh (the far end of the mesh does not need to care about local link quality changes that much). Other optimizations strategies, like reducing overhead, might be possible if OGMs weren't used for all tasks in the mesh at the same time. As a result detecting local link qualities shall be handled by an independent message type, ELP, whereas the OGM message type remains responsible for flooding the mesh with these link quality information and determining the overall path transmit qualities. Developed by Linus during a 6 months trainee study period in Ascom (Switzerland) AG. Signed-off-by: Linus Luessing <linus.luessing@web.de> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
2016-01-16 16:40:09 +08:00
/* Copyright (C) 2011-2016 B.A.T.M.A.N. contributors:
*
* Linus Lüssing, Marek Lindner
*
* 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, see <http://www.gnu.org/licenses/>.
*/
#include "bat_v_elp.h"
#include "main.h"
#include <linux/atomic.h>
#include <linux/byteorder/generic.h>
#include <linux/errno.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
batman-adv: ELP - adding basic infrastructure The B.A.T.M.A.N. protocol originally only used a single message type (called OGM) to determine the link qualities to the direct neighbors and spreading these link quality information through the whole mesh. This procedure is summarized on the BATMAN concept page and explained in details in the RFC draft published in 2008. This approach was chosen for its simplicity during the protocol design phase and the implementation. However, it also bears some drawbacks: * Wireless interfaces usually come with some packet loss, therefore a higher broadcast rate is desirable to allow a fast reaction on flaky connections. Other interfaces of the same host might be connected to Ethernet LANs / VPNs / etc which rarely exhibit packet loss would benefit from a lower broadcast rate to reduce overhead. * It generally is more desirable to detect local link quality changes at a faster rate than propagating all these changes through the entire mesh (the far end of the mesh does not need to care about local link quality changes that much). Other optimizations strategies, like reducing overhead, might be possible if OGMs weren't used for all tasks in the mesh at the same time. As a result detecting local link qualities shall be handled by an independent message type, ELP, whereas the OGM message type remains responsible for flooding the mesh with these link quality information and determining the overall path transmit qualities. Developed by Linus during a 6 months trainee study period in Ascom (Switzerland) AG. Signed-off-by: Linus Luessing <linus.luessing@web.de> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
2016-01-16 16:40:09 +08:00
#include <linux/fs.h>
#include <linux/if_ether.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/kref.h>
batman-adv: ELP - adding basic infrastructure The B.A.T.M.A.N. protocol originally only used a single message type (called OGM) to determine the link qualities to the direct neighbors and spreading these link quality information through the whole mesh. This procedure is summarized on the BATMAN concept page and explained in details in the RFC draft published in 2008. This approach was chosen for its simplicity during the protocol design phase and the implementation. However, it also bears some drawbacks: * Wireless interfaces usually come with some packet loss, therefore a higher broadcast rate is desirable to allow a fast reaction on flaky connections. Other interfaces of the same host might be connected to Ethernet LANs / VPNs / etc which rarely exhibit packet loss would benefit from a lower broadcast rate to reduce overhead. * It generally is more desirable to detect local link quality changes at a faster rate than propagating all these changes through the entire mesh (the far end of the mesh does not need to care about local link quality changes that much). Other optimizations strategies, like reducing overhead, might be possible if OGMs weren't used for all tasks in the mesh at the same time. As a result detecting local link qualities shall be handled by an independent message type, ELP, whereas the OGM message type remains responsible for flooding the mesh with these link quality information and determining the overall path transmit qualities. Developed by Linus during a 6 months trainee study period in Ascom (Switzerland) AG. Signed-off-by: Linus Luessing <linus.luessing@web.de> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
2016-01-16 16:40:09 +08:00
#include <linux/netdevice.h>
#include <linux/random.h>
#include <linux/rculist.h>
#include <linux/rcupdate.h>
#include <linux/rtnetlink.h>
batman-adv: ELP - adding basic infrastructure The B.A.T.M.A.N. protocol originally only used a single message type (called OGM) to determine the link qualities to the direct neighbors and spreading these link quality information through the whole mesh. This procedure is summarized on the BATMAN concept page and explained in details in the RFC draft published in 2008. This approach was chosen for its simplicity during the protocol design phase and the implementation. However, it also bears some drawbacks: * Wireless interfaces usually come with some packet loss, therefore a higher broadcast rate is desirable to allow a fast reaction on flaky connections. Other interfaces of the same host might be connected to Ethernet LANs / VPNs / etc which rarely exhibit packet loss would benefit from a lower broadcast rate to reduce overhead. * It generally is more desirable to detect local link quality changes at a faster rate than propagating all these changes through the entire mesh (the far end of the mesh does not need to care about local link quality changes that much). Other optimizations strategies, like reducing overhead, might be possible if OGMs weren't used for all tasks in the mesh at the same time. As a result detecting local link qualities shall be handled by an independent message type, ELP, whereas the OGM message type remains responsible for flooding the mesh with these link quality information and determining the overall path transmit qualities. Developed by Linus during a 6 months trainee study period in Ascom (Switzerland) AG. Signed-off-by: Linus Luessing <linus.luessing@web.de> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
2016-01-16 16:40:09 +08:00
#include <linux/skbuff.h>
#include <linux/stddef.h>
#include <linux/string.h>
#include <linux/types.h>
#include <linux/workqueue.h>
#include <net/cfg80211.h>
batman-adv: ELP - adding basic infrastructure The B.A.T.M.A.N. protocol originally only used a single message type (called OGM) to determine the link qualities to the direct neighbors and spreading these link quality information through the whole mesh. This procedure is summarized on the BATMAN concept page and explained in details in the RFC draft published in 2008. This approach was chosen for its simplicity during the protocol design phase and the implementation. However, it also bears some drawbacks: * Wireless interfaces usually come with some packet loss, therefore a higher broadcast rate is desirable to allow a fast reaction on flaky connections. Other interfaces of the same host might be connected to Ethernet LANs / VPNs / etc which rarely exhibit packet loss would benefit from a lower broadcast rate to reduce overhead. * It generally is more desirable to detect local link quality changes at a faster rate than propagating all these changes through the entire mesh (the far end of the mesh does not need to care about local link quality changes that much). Other optimizations strategies, like reducing overhead, might be possible if OGMs weren't used for all tasks in the mesh at the same time. As a result detecting local link qualities shall be handled by an independent message type, ELP, whereas the OGM message type remains responsible for flooding the mesh with these link quality information and determining the overall path transmit qualities. Developed by Linus during a 6 months trainee study period in Ascom (Switzerland) AG. Signed-off-by: Linus Luessing <linus.luessing@web.de> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
2016-01-16 16:40:09 +08:00
#include "bat_algo.h"
#include "bat_v_ogm.h"
batman-adv: ELP - adding basic infrastructure The B.A.T.M.A.N. protocol originally only used a single message type (called OGM) to determine the link qualities to the direct neighbors and spreading these link quality information through the whole mesh. This procedure is summarized on the BATMAN concept page and explained in details in the RFC draft published in 2008. This approach was chosen for its simplicity during the protocol design phase and the implementation. However, it also bears some drawbacks: * Wireless interfaces usually come with some packet loss, therefore a higher broadcast rate is desirable to allow a fast reaction on flaky connections. Other interfaces of the same host might be connected to Ethernet LANs / VPNs / etc which rarely exhibit packet loss would benefit from a lower broadcast rate to reduce overhead. * It generally is more desirable to detect local link quality changes at a faster rate than propagating all these changes through the entire mesh (the far end of the mesh does not need to care about local link quality changes that much). Other optimizations strategies, like reducing overhead, might be possible if OGMs weren't used for all tasks in the mesh at the same time. As a result detecting local link qualities shall be handled by an independent message type, ELP, whereas the OGM message type remains responsible for flooding the mesh with these link quality information and determining the overall path transmit qualities. Developed by Linus during a 6 months trainee study period in Ascom (Switzerland) AG. Signed-off-by: Linus Luessing <linus.luessing@web.de> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
2016-01-16 16:40:09 +08:00
#include "hard-interface.h"
#include "originator.h"
batman-adv: ELP - adding basic infrastructure The B.A.T.M.A.N. protocol originally only used a single message type (called OGM) to determine the link qualities to the direct neighbors and spreading these link quality information through the whole mesh. This procedure is summarized on the BATMAN concept page and explained in details in the RFC draft published in 2008. This approach was chosen for its simplicity during the protocol design phase and the implementation. However, it also bears some drawbacks: * Wireless interfaces usually come with some packet loss, therefore a higher broadcast rate is desirable to allow a fast reaction on flaky connections. Other interfaces of the same host might be connected to Ethernet LANs / VPNs / etc which rarely exhibit packet loss would benefit from a lower broadcast rate to reduce overhead. * It generally is more desirable to detect local link quality changes at a faster rate than propagating all these changes through the entire mesh (the far end of the mesh does not need to care about local link quality changes that much). Other optimizations strategies, like reducing overhead, might be possible if OGMs weren't used for all tasks in the mesh at the same time. As a result detecting local link qualities shall be handled by an independent message type, ELP, whereas the OGM message type remains responsible for flooding the mesh with these link quality information and determining the overall path transmit qualities. Developed by Linus during a 6 months trainee study period in Ascom (Switzerland) AG. Signed-off-by: Linus Luessing <linus.luessing@web.de> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
2016-01-16 16:40:09 +08:00
#include "packet.h"
#include "routing.h"
batman-adv: ELP - adding basic infrastructure The B.A.T.M.A.N. protocol originally only used a single message type (called OGM) to determine the link qualities to the direct neighbors and spreading these link quality information through the whole mesh. This procedure is summarized on the BATMAN concept page and explained in details in the RFC draft published in 2008. This approach was chosen for its simplicity during the protocol design phase and the implementation. However, it also bears some drawbacks: * Wireless interfaces usually come with some packet loss, therefore a higher broadcast rate is desirable to allow a fast reaction on flaky connections. Other interfaces of the same host might be connected to Ethernet LANs / VPNs / etc which rarely exhibit packet loss would benefit from a lower broadcast rate to reduce overhead. * It generally is more desirable to detect local link quality changes at a faster rate than propagating all these changes through the entire mesh (the far end of the mesh does not need to care about local link quality changes that much). Other optimizations strategies, like reducing overhead, might be possible if OGMs weren't used for all tasks in the mesh at the same time. As a result detecting local link qualities shall be handled by an independent message type, ELP, whereas the OGM message type remains responsible for flooding the mesh with these link quality information and determining the overall path transmit qualities. Developed by Linus during a 6 months trainee study period in Ascom (Switzerland) AG. Signed-off-by: Linus Luessing <linus.luessing@web.de> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
2016-01-16 16:40:09 +08:00
#include "send.h"
/**
* batadv_v_elp_start_timer - restart timer for ELP periodic work
* @hard_iface: the interface for which the timer has to be reset
*/
static void batadv_v_elp_start_timer(struct batadv_hard_iface *hard_iface)
{
unsigned int msecs;
msecs = atomic_read(&hard_iface->bat_v.elp_interval) - BATADV_JITTER;
msecs += prandom_u32() % (2 * BATADV_JITTER);
queue_delayed_work(batadv_event_workqueue, &hard_iface->bat_v.elp_wq,
msecs_to_jiffies(msecs));
}
/**
* batadv_v_elp_get_throughput - get the throughput towards a neighbour
* @neigh: the neighbour for which the throughput has to be obtained
*
* Return: The throughput towards the given neighbour in multiples of 100kpbs
* (a value of '1' equals to 0.1Mbps, '10' equals 1Mbps, etc).
*/
static u32 batadv_v_elp_get_throughput(struct batadv_hardif_neigh_node *neigh)
{
struct batadv_hard_iface *hard_iface = neigh->if_incoming;
struct ethtool_link_ksettings link_settings;
struct station_info sinfo;
u32 throughput;
int ret;
/* if the user specified a customised value for this interface, then
* return it directly
*/
throughput = atomic_read(&hard_iface->bat_v.throughput_override);
if (throughput != 0)
return throughput;
/* if this is a wireless device, then ask its throughput through
* cfg80211 API
*/
if (batadv_is_wifi_netdev(hard_iface->net_dev)) {
if (hard_iface->net_dev->ieee80211_ptr) {
ret = cfg80211_get_station(hard_iface->net_dev,
neigh->addr, &sinfo);
if (ret == -ENOENT) {
/* Node is not associated anymore! It would be
* possible to delete this neighbor. For now set
* the throughput metric to 0.
*/
return 0;
}
if (!ret)
return sinfo.expected_throughput / 100;
}
/* unsupported WiFi driver version */
goto default_throughput;
}
/* if not a wifi interface, check if this device provides data via
* ethtool (e.g. an Ethernet adapter)
*/
memset(&link_settings, 0, sizeof(link_settings));
rtnl_lock();
ret = __ethtool_get_link_ksettings(hard_iface->net_dev, &link_settings);
rtnl_unlock();
if (ret == 0) {
/* link characteristics might change over time */
if (link_settings.base.duplex == DUPLEX_FULL)
hard_iface->bat_v.flags |= BATADV_FULL_DUPLEX;
else
hard_iface->bat_v.flags &= ~BATADV_FULL_DUPLEX;
throughput = link_settings.base.speed;
if (throughput && (throughput != SPEED_UNKNOWN))
return throughput * 10;
}
default_throughput:
if (!(hard_iface->bat_v.flags & BATADV_WARNING_DEFAULT)) {
batadv_info(hard_iface->soft_iface,
"WiFi driver or ethtool info does not provide information about link speeds on interface %s, therefore defaulting to hardcoded throughput values of %u.%1u Mbps. Consider overriding the throughput manually or checking your driver.\n",
hard_iface->net_dev->name,
BATADV_THROUGHPUT_DEFAULT_VALUE / 10,
BATADV_THROUGHPUT_DEFAULT_VALUE % 10);
hard_iface->bat_v.flags |= BATADV_WARNING_DEFAULT;
}
/* if none of the above cases apply, return the base_throughput */
return BATADV_THROUGHPUT_DEFAULT_VALUE;
}
/**
* batadv_v_elp_throughput_metric_update - worker updating the throughput metric
* of a single hop neighbour
* @work: the work queue item
*/
void batadv_v_elp_throughput_metric_update(struct work_struct *work)
{
struct batadv_hardif_neigh_node_bat_v *neigh_bat_v;
struct batadv_hardif_neigh_node *neigh;
neigh_bat_v = container_of(work, struct batadv_hardif_neigh_node_bat_v,
metric_work);
neigh = container_of(neigh_bat_v, struct batadv_hardif_neigh_node,
bat_v);
ewma_throughput_add(&neigh->bat_v.throughput,
batadv_v_elp_get_throughput(neigh));
/* decrement refcounter to balance increment performed before scheduling
* this task
*/
batadv_hardif_neigh_put(neigh);
}
batman-adv: ELP - adding basic infrastructure The B.A.T.M.A.N. protocol originally only used a single message type (called OGM) to determine the link qualities to the direct neighbors and spreading these link quality information through the whole mesh. This procedure is summarized on the BATMAN concept page and explained in details in the RFC draft published in 2008. This approach was chosen for its simplicity during the protocol design phase and the implementation. However, it also bears some drawbacks: * Wireless interfaces usually come with some packet loss, therefore a higher broadcast rate is desirable to allow a fast reaction on flaky connections. Other interfaces of the same host might be connected to Ethernet LANs / VPNs / etc which rarely exhibit packet loss would benefit from a lower broadcast rate to reduce overhead. * It generally is more desirable to detect local link quality changes at a faster rate than propagating all these changes through the entire mesh (the far end of the mesh does not need to care about local link quality changes that much). Other optimizations strategies, like reducing overhead, might be possible if OGMs weren't used for all tasks in the mesh at the same time. As a result detecting local link qualities shall be handled by an independent message type, ELP, whereas the OGM message type remains responsible for flooding the mesh with these link quality information and determining the overall path transmit qualities. Developed by Linus during a 6 months trainee study period in Ascom (Switzerland) AG. Signed-off-by: Linus Luessing <linus.luessing@web.de> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
2016-01-16 16:40:09 +08:00
/**
* batadv_v_elp_periodic_work - ELP periodic task per interface
* @work: work queue item
*
* Emits broadcast ELP message in regular intervals.
*/
static void batadv_v_elp_periodic_work(struct work_struct *work)
{
struct batadv_hardif_neigh_node *hardif_neigh;
batman-adv: ELP - adding basic infrastructure The B.A.T.M.A.N. protocol originally only used a single message type (called OGM) to determine the link qualities to the direct neighbors and spreading these link quality information through the whole mesh. This procedure is summarized on the BATMAN concept page and explained in details in the RFC draft published in 2008. This approach was chosen for its simplicity during the protocol design phase and the implementation. However, it also bears some drawbacks: * Wireless interfaces usually come with some packet loss, therefore a higher broadcast rate is desirable to allow a fast reaction on flaky connections. Other interfaces of the same host might be connected to Ethernet LANs / VPNs / etc which rarely exhibit packet loss would benefit from a lower broadcast rate to reduce overhead. * It generally is more desirable to detect local link quality changes at a faster rate than propagating all these changes through the entire mesh (the far end of the mesh does not need to care about local link quality changes that much). Other optimizations strategies, like reducing overhead, might be possible if OGMs weren't used for all tasks in the mesh at the same time. As a result detecting local link qualities shall be handled by an independent message type, ELP, whereas the OGM message type remains responsible for flooding the mesh with these link quality information and determining the overall path transmit qualities. Developed by Linus during a 6 months trainee study period in Ascom (Switzerland) AG. Signed-off-by: Linus Luessing <linus.luessing@web.de> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
2016-01-16 16:40:09 +08:00
struct batadv_hard_iface *hard_iface;
struct batadv_hard_iface_bat_v *bat_v;
struct batadv_elp_packet *elp_packet;
struct batadv_priv *bat_priv;
struct sk_buff *skb;
u32 elp_interval;
bat_v = container_of(work, struct batadv_hard_iface_bat_v, elp_wq.work);
hard_iface = container_of(bat_v, struct batadv_hard_iface, bat_v);
bat_priv = netdev_priv(hard_iface->soft_iface);
if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_DEACTIVATING)
goto out;
/* we are in the process of shutting this interface down */
if ((hard_iface->if_status == BATADV_IF_NOT_IN_USE) ||
(hard_iface->if_status == BATADV_IF_TO_BE_REMOVED))
goto out;
/* the interface was enabled but may not be ready yet */
if (hard_iface->if_status != BATADV_IF_ACTIVE)
goto restart_timer;
skb = skb_copy(hard_iface->bat_v.elp_skb, GFP_ATOMIC);
if (!skb)
goto restart_timer;
elp_packet = (struct batadv_elp_packet *)skb->data;
elp_packet->seqno = htonl(atomic_read(&hard_iface->bat_v.elp_seqno));
elp_interval = atomic_read(&hard_iface->bat_v.elp_interval);
elp_packet->elp_interval = htonl(elp_interval);
batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
"Sending broadcast ELP packet on interface %s, seqno %u\n",
hard_iface->net_dev->name,
atomic_read(&hard_iface->bat_v.elp_seqno));
batadv_send_broadcast_skb(skb, hard_iface);
batman-adv: ELP - adding basic infrastructure The B.A.T.M.A.N. protocol originally only used a single message type (called OGM) to determine the link qualities to the direct neighbors and spreading these link quality information through the whole mesh. This procedure is summarized on the BATMAN concept page and explained in details in the RFC draft published in 2008. This approach was chosen for its simplicity during the protocol design phase and the implementation. However, it also bears some drawbacks: * Wireless interfaces usually come with some packet loss, therefore a higher broadcast rate is desirable to allow a fast reaction on flaky connections. Other interfaces of the same host might be connected to Ethernet LANs / VPNs / etc which rarely exhibit packet loss would benefit from a lower broadcast rate to reduce overhead. * It generally is more desirable to detect local link quality changes at a faster rate than propagating all these changes through the entire mesh (the far end of the mesh does not need to care about local link quality changes that much). Other optimizations strategies, like reducing overhead, might be possible if OGMs weren't used for all tasks in the mesh at the same time. As a result detecting local link qualities shall be handled by an independent message type, ELP, whereas the OGM message type remains responsible for flooding the mesh with these link quality information and determining the overall path transmit qualities. Developed by Linus during a 6 months trainee study period in Ascom (Switzerland) AG. Signed-off-by: Linus Luessing <linus.luessing@web.de> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
2016-01-16 16:40:09 +08:00
atomic_inc(&hard_iface->bat_v.elp_seqno);
/* The throughput metric is updated on each sent packet. This way, if a
* node is dead and no longer sends packets, batman-adv is still able to
* react timely to its death.
*
* The throughput metric is updated by following these steps:
* 1) if the hard_iface is wifi => send a number of unicast ELPs for
* probing/sampling to each neighbor
* 2) update the throughput metric value of each neighbor (note that the
* value retrieved in this step might be 100ms old because the
* probing packets at point 1) could still be in the HW queue)
*/
rcu_read_lock();
hlist_for_each_entry_rcu(hardif_neigh, &hard_iface->neigh_list, list) {
if (!kref_get_unless_zero(&hardif_neigh->refcount))
continue;
/* Reading the estimated throughput from cfg80211 is a task that
* may sleep and that is not allowed in an rcu protected
* context. Therefore schedule a task for that.
*/
queue_work(batadv_event_workqueue,
&hardif_neigh->bat_v.metric_work);
}
rcu_read_unlock();
batman-adv: ELP - adding basic infrastructure The B.A.T.M.A.N. protocol originally only used a single message type (called OGM) to determine the link qualities to the direct neighbors and spreading these link quality information through the whole mesh. This procedure is summarized on the BATMAN concept page and explained in details in the RFC draft published in 2008. This approach was chosen for its simplicity during the protocol design phase and the implementation. However, it also bears some drawbacks: * Wireless interfaces usually come with some packet loss, therefore a higher broadcast rate is desirable to allow a fast reaction on flaky connections. Other interfaces of the same host might be connected to Ethernet LANs / VPNs / etc which rarely exhibit packet loss would benefit from a lower broadcast rate to reduce overhead. * It generally is more desirable to detect local link quality changes at a faster rate than propagating all these changes through the entire mesh (the far end of the mesh does not need to care about local link quality changes that much). Other optimizations strategies, like reducing overhead, might be possible if OGMs weren't used for all tasks in the mesh at the same time. As a result detecting local link qualities shall be handled by an independent message type, ELP, whereas the OGM message type remains responsible for flooding the mesh with these link quality information and determining the overall path transmit qualities. Developed by Linus during a 6 months trainee study period in Ascom (Switzerland) AG. Signed-off-by: Linus Luessing <linus.luessing@web.de> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
2016-01-16 16:40:09 +08:00
restart_timer:
batadv_v_elp_start_timer(hard_iface);
out:
return;
}
/**
* batadv_v_elp_iface_enable - setup the ELP interface private resources
* @hard_iface: interface for which the data has to be prepared
*
* Return: 0 on success or a -ENOMEM in case of failure.
*/
int batadv_v_elp_iface_enable(struct batadv_hard_iface *hard_iface)
{
struct batadv_elp_packet *elp_packet;
unsigned char *elp_buff;
u32 random_seqno;
size_t size;
int res = -ENOMEM;
size = ETH_HLEN + NET_IP_ALIGN + BATADV_ELP_HLEN;
hard_iface->bat_v.elp_skb = dev_alloc_skb(size);
if (!hard_iface->bat_v.elp_skb)
goto out;
skb_reserve(hard_iface->bat_v.elp_skb, ETH_HLEN + NET_IP_ALIGN);
elp_buff = skb_push(hard_iface->bat_v.elp_skb, BATADV_ELP_HLEN);
elp_packet = (struct batadv_elp_packet *)elp_buff;
memset(elp_packet, 0, BATADV_ELP_HLEN);
elp_packet->packet_type = BATADV_ELP;
elp_packet->version = BATADV_COMPAT_VERSION;
/* randomize initial seqno to avoid collision */
get_random_bytes(&random_seqno, sizeof(random_seqno));
atomic_set(&hard_iface->bat_v.elp_seqno, random_seqno);
atomic_set(&hard_iface->bat_v.elp_interval, 500);
/* assume full-duplex by default */
hard_iface->bat_v.flags |= BATADV_FULL_DUPLEX;
/* warn the user (again) if there is no throughput data is available */
hard_iface->bat_v.flags &= ~BATADV_WARNING_DEFAULT;
if (batadv_is_wifi_netdev(hard_iface->net_dev))
hard_iface->bat_v.flags &= ~BATADV_FULL_DUPLEX;
batman-adv: ELP - adding basic infrastructure The B.A.T.M.A.N. protocol originally only used a single message type (called OGM) to determine the link qualities to the direct neighbors and spreading these link quality information through the whole mesh. This procedure is summarized on the BATMAN concept page and explained in details in the RFC draft published in 2008. This approach was chosen for its simplicity during the protocol design phase and the implementation. However, it also bears some drawbacks: * Wireless interfaces usually come with some packet loss, therefore a higher broadcast rate is desirable to allow a fast reaction on flaky connections. Other interfaces of the same host might be connected to Ethernet LANs / VPNs / etc which rarely exhibit packet loss would benefit from a lower broadcast rate to reduce overhead. * It generally is more desirable to detect local link quality changes at a faster rate than propagating all these changes through the entire mesh (the far end of the mesh does not need to care about local link quality changes that much). Other optimizations strategies, like reducing overhead, might be possible if OGMs weren't used for all tasks in the mesh at the same time. As a result detecting local link qualities shall be handled by an independent message type, ELP, whereas the OGM message type remains responsible for flooding the mesh with these link quality information and determining the overall path transmit qualities. Developed by Linus during a 6 months trainee study period in Ascom (Switzerland) AG. Signed-off-by: Linus Luessing <linus.luessing@web.de> Signed-off-by: Marek Lindner <mareklindner@neomailbox.ch> Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
2016-01-16 16:40:09 +08:00
INIT_DELAYED_WORK(&hard_iface->bat_v.elp_wq,
batadv_v_elp_periodic_work);
batadv_v_elp_start_timer(hard_iface);
res = 0;
out:
return res;
}
/**
* batadv_v_elp_iface_disable - release ELP interface private resources
* @hard_iface: interface for which the resources have to be released
*/
void batadv_v_elp_iface_disable(struct batadv_hard_iface *hard_iface)
{
cancel_delayed_work_sync(&hard_iface->bat_v.elp_wq);
dev_kfree_skb(hard_iface->bat_v.elp_skb);
hard_iface->bat_v.elp_skb = NULL;
}
/**
* batadv_v_elp_primary_iface_set - change internal data to reflect the new
* primary interface
* @primary_iface: the new primary interface
*/
void batadv_v_elp_primary_iface_set(struct batadv_hard_iface *primary_iface)
{
struct batadv_hard_iface *hard_iface;
struct batadv_elp_packet *elp_packet;
struct sk_buff *skb;
/* update orig field of every elp iface belonging to this mesh */
rcu_read_lock();
list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
if (primary_iface->soft_iface != hard_iface->soft_iface)
continue;
if (!hard_iface->bat_v.elp_skb)
continue;
skb = hard_iface->bat_v.elp_skb;
elp_packet = (struct batadv_elp_packet *)skb->data;
ether_addr_copy(elp_packet->orig,
primary_iface->net_dev->dev_addr);
}
rcu_read_unlock();
}
/**
* batadv_v_elp_neigh_update - update an ELP neighbour node
* @bat_priv: the bat priv with all the soft interface information
* @neigh_addr: the neighbour interface address
* @if_incoming: the interface the packet was received through
* @elp_packet: the received ELP packet
*
* Updates the ELP neighbour node state with the data received within the new
* ELP packet.
*/
static void batadv_v_elp_neigh_update(struct batadv_priv *bat_priv,
u8 *neigh_addr,
struct batadv_hard_iface *if_incoming,
struct batadv_elp_packet *elp_packet)
{
struct batadv_neigh_node *neigh;
struct batadv_orig_node *orig_neigh;
struct batadv_hardif_neigh_node *hardif_neigh;
s32 seqno_diff;
s32 elp_latest_seqno;
orig_neigh = batadv_v_ogm_orig_get(bat_priv, elp_packet->orig);
if (!orig_neigh)
return;
neigh = batadv_neigh_node_new(orig_neigh, if_incoming, neigh_addr);
if (!neigh)
goto orig_free;
hardif_neigh = batadv_hardif_neigh_get(if_incoming, neigh_addr);
if (!hardif_neigh)
goto neigh_free;
elp_latest_seqno = hardif_neigh->bat_v.elp_latest_seqno;
seqno_diff = ntohl(elp_packet->seqno) - elp_latest_seqno;
/* known or older sequence numbers are ignored. However always adopt
* if the router seems to have been restarted.
*/
if (seqno_diff < 1 && seqno_diff > -BATADV_ELP_MAX_AGE)
goto hardif_free;
neigh->last_seen = jiffies;
hardif_neigh->last_seen = jiffies;
hardif_neigh->bat_v.elp_latest_seqno = ntohl(elp_packet->seqno);
hardif_neigh->bat_v.elp_interval = ntohl(elp_packet->elp_interval);
hardif_free:
if (hardif_neigh)
batadv_hardif_neigh_put(hardif_neigh);
neigh_free:
if (neigh)
batadv_neigh_node_put(neigh);
orig_free:
if (orig_neigh)
batadv_orig_node_put(orig_neigh);
}
/**
* batadv_v_elp_packet_recv - main ELP packet handler
* @skb: the received packet
* @if_incoming: the interface this packet was received through
*
* Return: NET_RX_SUCCESS and consumes the skb if the packet was peoperly
* processed or NET_RX_DROP in case of failure.
*/
int batadv_v_elp_packet_recv(struct sk_buff *skb,
struct batadv_hard_iface *if_incoming)
{
struct batadv_priv *bat_priv = netdev_priv(if_incoming->soft_iface);
struct batadv_elp_packet *elp_packet;
struct batadv_hard_iface *primary_if;
struct ethhdr *ethhdr = (struct ethhdr *)skb_mac_header(skb);
bool ret;
ret = batadv_check_management_packet(skb, if_incoming, BATADV_ELP_HLEN);
if (!ret)
return NET_RX_DROP;
if (batadv_is_my_mac(bat_priv, ethhdr->h_source))
return NET_RX_DROP;
/* did we receive a B.A.T.M.A.N. V ELP packet on an interface
* that does not have B.A.T.M.A.N. V ELP enabled ?
*/
if (strcmp(bat_priv->bat_algo_ops->name, "BATMAN_V") != 0)
return NET_RX_DROP;
elp_packet = (struct batadv_elp_packet *)skb->data;
batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
"Received ELP packet from %pM seqno %u ORIG: %pM\n",
ethhdr->h_source, ntohl(elp_packet->seqno),
elp_packet->orig);
primary_if = batadv_primary_if_get_selected(bat_priv);
if (!primary_if)
goto out;
batadv_v_elp_neigh_update(bat_priv, ethhdr->h_source, if_incoming,
elp_packet);
out:
if (primary_if)
batadv_hardif_put(primary_if);
consume_skb(skb);
return NET_RX_SUCCESS;
}