Two be able to network code two packets, one packet must be buffered until the next is available. This is done in a "coding buffer", which is essentially a hash table with lists of packets. Each entry in the hash table corresponds to a specific src-dst pair, which has a linked list of packets that are buffered. This patch adds skbs to the buffer just before forwarding them. The buffer is traversed every 10 ms, where timed skbs are removed from the buffer and transmitted. To allow experiments with the network coding scheme, the timeout is tunable through a file in debugfs. Signed-off-by: Martin Hundebøll <martin@hundeboll.net> Signed-off-by: Marek Lindner <lindner_marek@yahoo.de> Signed-off-by: Antonio Quartulli <ordex@autistici.org>
982 lines
28 KiB
C
982 lines
28 KiB
C
/* Copyright (C) 2012-2013 B.A.T.M.A.N. contributors:
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*
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* Martin Hundebøll, Jeppe Ledet-Pedersen
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of version 2 of the GNU General Public
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* License as published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful, but
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* WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
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* 02110-1301, USA
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*/
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#include <linux/debugfs.h>
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#include "main.h"
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#include "hash.h"
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#include "network-coding.h"
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#include "send.h"
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#include "originator.h"
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#include "hard-interface.h"
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static struct lock_class_key batadv_nc_coding_hash_lock_class_key;
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static void batadv_nc_worker(struct work_struct *work);
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/**
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* batadv_nc_start_timer - initialise the nc periodic worker
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* @bat_priv: the bat priv with all the soft interface information
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*/
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static void batadv_nc_start_timer(struct batadv_priv *bat_priv)
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{
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queue_delayed_work(batadv_event_workqueue, &bat_priv->nc.work,
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msecs_to_jiffies(10));
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}
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/**
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* batadv_nc_init - initialise coding hash table and start house keeping
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* @bat_priv: the bat priv with all the soft interface information
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*/
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int batadv_nc_init(struct batadv_priv *bat_priv)
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{
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bat_priv->nc.timestamp_fwd_flush = jiffies;
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if (bat_priv->nc.coding_hash)
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return 0;
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bat_priv->nc.coding_hash = batadv_hash_new(128);
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if (!bat_priv->nc.coding_hash)
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goto err;
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batadv_hash_set_lock_class(bat_priv->nc.coding_hash,
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&batadv_nc_coding_hash_lock_class_key);
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INIT_DELAYED_WORK(&bat_priv->nc.work, batadv_nc_worker);
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batadv_nc_start_timer(bat_priv);
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return 0;
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err:
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return -ENOMEM;
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}
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/**
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* batadv_nc_init_bat_priv - initialise the nc specific bat_priv variables
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* @bat_priv: the bat priv with all the soft interface information
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*/
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void batadv_nc_init_bat_priv(struct batadv_priv *bat_priv)
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{
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atomic_set(&bat_priv->network_coding, 1);
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bat_priv->nc.min_tq = 200;
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bat_priv->nc.max_fwd_delay = 10;
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}
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/**
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* batadv_nc_init_orig - initialise the nc fields of an orig_node
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* @orig_node: the orig_node which is going to be initialised
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*/
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void batadv_nc_init_orig(struct batadv_orig_node *orig_node)
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{
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INIT_LIST_HEAD(&orig_node->in_coding_list);
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INIT_LIST_HEAD(&orig_node->out_coding_list);
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spin_lock_init(&orig_node->in_coding_list_lock);
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spin_lock_init(&orig_node->out_coding_list_lock);
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}
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/**
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* batadv_nc_node_free_rcu - rcu callback to free an nc node and remove
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* its refcount on the orig_node
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* @rcu: rcu pointer of the nc node
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*/
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static void batadv_nc_node_free_rcu(struct rcu_head *rcu)
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{
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struct batadv_nc_node *nc_node;
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nc_node = container_of(rcu, struct batadv_nc_node, rcu);
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batadv_orig_node_free_ref(nc_node->orig_node);
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kfree(nc_node);
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}
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/**
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* batadv_nc_node_free_ref - decrements the nc node refcounter and possibly
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* frees it
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* @nc_node: the nc node to free
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*/
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static void batadv_nc_node_free_ref(struct batadv_nc_node *nc_node)
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{
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if (atomic_dec_and_test(&nc_node->refcount))
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call_rcu(&nc_node->rcu, batadv_nc_node_free_rcu);
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}
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/**
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* batadv_nc_path_free_ref - decrements the nc path refcounter and possibly
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* frees it
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* @nc_path: the nc node to free
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*/
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static void batadv_nc_path_free_ref(struct batadv_nc_path *nc_path)
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{
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if (atomic_dec_and_test(&nc_path->refcount))
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kfree_rcu(nc_path, rcu);
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}
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/**
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* batadv_nc_packet_free - frees nc packet
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* @nc_packet: the nc packet to free
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*/
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static void batadv_nc_packet_free(struct batadv_nc_packet *nc_packet)
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{
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if (nc_packet->skb)
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kfree_skb(nc_packet->skb);
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batadv_nc_path_free_ref(nc_packet->nc_path);
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kfree(nc_packet);
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}
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/**
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* batadv_nc_to_purge_nc_node - checks whether an nc node has to be purged
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* @bat_priv: the bat priv with all the soft interface information
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* @nc_node: the nc node to check
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*
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* Returns true if the entry has to be purged now, false otherwise
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*/
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static bool batadv_nc_to_purge_nc_node(struct batadv_priv *bat_priv,
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struct batadv_nc_node *nc_node)
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{
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if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
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return true;
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return batadv_has_timed_out(nc_node->last_seen, BATADV_NC_NODE_TIMEOUT);
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}
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/**
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* batadv_nc_to_purge_nc_path_coding - checks whether an nc path has timed out
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* @bat_priv: the bat priv with all the soft interface information
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* @nc_path: the nc path to check
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*
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* Returns true if the entry has to be purged now, false otherwise
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*/
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static bool batadv_nc_to_purge_nc_path_coding(struct batadv_priv *bat_priv,
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struct batadv_nc_path *nc_path)
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{
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if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
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return true;
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/* purge the path when no packets has been added for 10 times the
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* max_fwd_delay time
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*/
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return batadv_has_timed_out(nc_path->last_valid,
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bat_priv->nc.max_fwd_delay * 10);
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}
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/**
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* batadv_nc_purge_orig_nc_nodes - go through list of nc nodes and purge stale
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* entries
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* @bat_priv: the bat priv with all the soft interface information
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* @list: list of nc nodes
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* @lock: nc node list lock
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* @to_purge: function in charge to decide whether an entry has to be purged or
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* not. This function takes the nc node as argument and has to return
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* a boolean value: true if the entry has to be deleted, false
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* otherwise
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*/
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static void
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batadv_nc_purge_orig_nc_nodes(struct batadv_priv *bat_priv,
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struct list_head *list,
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spinlock_t *lock,
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bool (*to_purge)(struct batadv_priv *,
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struct batadv_nc_node *))
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{
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struct batadv_nc_node *nc_node, *nc_node_tmp;
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/* For each nc_node in list */
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spin_lock_bh(lock);
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list_for_each_entry_safe(nc_node, nc_node_tmp, list, list) {
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/* if an helper function has been passed as parameter,
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* ask it if the entry has to be purged or not
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*/
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if (to_purge && !to_purge(bat_priv, nc_node))
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continue;
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batadv_dbg(BATADV_DBG_NC, bat_priv,
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"Removing nc_node %pM -> %pM\n",
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nc_node->addr, nc_node->orig_node->orig);
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list_del_rcu(&nc_node->list);
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batadv_nc_node_free_ref(nc_node);
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}
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spin_unlock_bh(lock);
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}
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/**
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* batadv_nc_purge_orig - purges all nc node data attached of the given
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* originator
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* @bat_priv: the bat priv with all the soft interface information
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* @orig_node: orig_node with the nc node entries to be purged
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* @to_purge: function in charge to decide whether an entry has to be purged or
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* not. This function takes the nc node as argument and has to return
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* a boolean value: true is the entry has to be deleted, false
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* otherwise
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*/
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void batadv_nc_purge_orig(struct batadv_priv *bat_priv,
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struct batadv_orig_node *orig_node,
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bool (*to_purge)(struct batadv_priv *,
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struct batadv_nc_node *))
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{
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/* Check ingoing nc_node's of this orig_node */
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batadv_nc_purge_orig_nc_nodes(bat_priv, &orig_node->in_coding_list,
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&orig_node->in_coding_list_lock,
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to_purge);
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/* Check outgoing nc_node's of this orig_node */
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batadv_nc_purge_orig_nc_nodes(bat_priv, &orig_node->out_coding_list,
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&orig_node->out_coding_list_lock,
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to_purge);
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}
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/**
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* batadv_nc_purge_orig_hash - traverse entire originator hash to check if they
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* have timed out nc nodes
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* @bat_priv: the bat priv with all the soft interface information
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*/
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static void batadv_nc_purge_orig_hash(struct batadv_priv *bat_priv)
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{
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struct batadv_hashtable *hash = bat_priv->orig_hash;
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struct hlist_head *head;
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struct batadv_orig_node *orig_node;
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uint32_t i;
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if (!hash)
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return;
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/* For each orig_node */
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for (i = 0; i < hash->size; i++) {
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head = &hash->table[i];
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rcu_read_lock();
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hlist_for_each_entry_rcu(orig_node, head, hash_entry)
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batadv_nc_purge_orig(bat_priv, orig_node,
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batadv_nc_to_purge_nc_node);
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rcu_read_unlock();
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}
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}
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/**
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* batadv_nc_purge_paths - traverse all nc paths part of the hash and remove
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* unused ones
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* @bat_priv: the bat priv with all the soft interface information
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* @hash: hash table containing the nc paths to check
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* @to_purge: function in charge to decide whether an entry has to be purged or
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* not. This function takes the nc node as argument and has to return
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* a boolean value: true is the entry has to be deleted, false
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* otherwise
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*/
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static void batadv_nc_purge_paths(struct batadv_priv *bat_priv,
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struct batadv_hashtable *hash,
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bool (*to_purge)(struct batadv_priv *,
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struct batadv_nc_path *))
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{
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struct hlist_head *head;
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struct hlist_node *node_tmp;
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struct batadv_nc_path *nc_path;
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spinlock_t *lock; /* Protects lists in hash */
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uint32_t i;
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for (i = 0; i < hash->size; i++) {
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head = &hash->table[i];
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lock = &hash->list_locks[i];
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/* For each nc_path in this bin */
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spin_lock_bh(lock);
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hlist_for_each_entry_safe(nc_path, node_tmp, head, hash_entry) {
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/* if an helper function has been passed as parameter,
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* ask it if the entry has to be purged or not
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*/
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if (to_purge && !to_purge(bat_priv, nc_path))
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continue;
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/* purging an non-empty nc_path should never happen, but
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* is observed under high CPU load. Delay the purging
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* until next iteration to allow the packet_list to be
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* emptied first.
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*/
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if (!unlikely(list_empty(&nc_path->packet_list))) {
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net_ratelimited_function(printk,
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KERN_WARNING
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"Skipping free of non-empty nc_path (%pM -> %pM)!\n",
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nc_path->prev_hop,
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nc_path->next_hop);
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continue;
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}
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/* nc_path is unused, so remove it */
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batadv_dbg(BATADV_DBG_NC, bat_priv,
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"Remove nc_path %pM -> %pM\n",
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nc_path->prev_hop, nc_path->next_hop);
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hlist_del_rcu(&nc_path->hash_entry);
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batadv_nc_path_free_ref(nc_path);
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}
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spin_unlock_bh(lock);
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}
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}
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/**
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* batadv_nc_hash_key_gen - computes the nc_path hash key
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* @key: buffer to hold the final hash key
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* @src: source ethernet mac address going into the hash key
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* @dst: destination ethernet mac address going into the hash key
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*/
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static void batadv_nc_hash_key_gen(struct batadv_nc_path *key, const char *src,
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const char *dst)
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{
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memcpy(key->prev_hop, src, sizeof(key->prev_hop));
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memcpy(key->next_hop, dst, sizeof(key->next_hop));
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}
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/**
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* batadv_nc_hash_choose - compute the hash value for an nc path
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* @data: data to hash
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* @size: size of the hash table
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*
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* Returns the selected index in the hash table for the given data.
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*/
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static uint32_t batadv_nc_hash_choose(const void *data, uint32_t size)
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{
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const struct batadv_nc_path *nc_path = data;
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uint32_t hash = 0;
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hash = batadv_hash_bytes(hash, &nc_path->prev_hop,
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sizeof(nc_path->prev_hop));
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hash = batadv_hash_bytes(hash, &nc_path->next_hop,
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sizeof(nc_path->next_hop));
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hash += (hash << 3);
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hash ^= (hash >> 11);
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hash += (hash << 15);
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return hash % size;
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}
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/**
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* batadv_nc_hash_compare - comparing function used in the network coding hash
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* tables
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* @node: node in the local table
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* @data2: second object to compare the node to
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*
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* Returns 1 if the two entry are the same, 0 otherwise
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*/
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static int batadv_nc_hash_compare(const struct hlist_node *node,
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const void *data2)
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{
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const struct batadv_nc_path *nc_path1, *nc_path2;
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nc_path1 = container_of(node, struct batadv_nc_path, hash_entry);
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nc_path2 = data2;
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/* Return 1 if the two keys are identical */
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if (memcmp(nc_path1->prev_hop, nc_path2->prev_hop,
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sizeof(nc_path1->prev_hop)) != 0)
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return 0;
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if (memcmp(nc_path1->next_hop, nc_path2->next_hop,
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sizeof(nc_path1->next_hop)) != 0)
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return 0;
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return 1;
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}
|
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|
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/**
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* batadv_nc_hash_find - search for an existing nc path and return it
|
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* @hash: hash table containing the nc path
|
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* @data: search key
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*
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* Returns the nc_path if found, NULL otherwise.
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*/
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static struct batadv_nc_path *
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batadv_nc_hash_find(struct batadv_hashtable *hash,
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void *data)
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{
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struct hlist_head *head;
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struct batadv_nc_path *nc_path, *nc_path_tmp = NULL;
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int index;
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if (!hash)
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return NULL;
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index = batadv_nc_hash_choose(data, hash->size);
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head = &hash->table[index];
|
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|
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rcu_read_lock();
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hlist_for_each_entry_rcu(nc_path, head, hash_entry) {
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if (!batadv_nc_hash_compare(&nc_path->hash_entry, data))
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continue;
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|
|
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if (!atomic_inc_not_zero(&nc_path->refcount))
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continue;
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nc_path_tmp = nc_path;
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break;
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}
|
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rcu_read_unlock();
|
|
|
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return nc_path_tmp;
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}
|
|
|
|
/**
|
|
* batadv_nc_send_packet - send non-coded packet and free nc_packet struct
|
|
* @nc_packet: the nc packet to send
|
|
*/
|
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static void batadv_nc_send_packet(struct batadv_nc_packet *nc_packet)
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{
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batadv_send_skb_packet(nc_packet->skb,
|
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nc_packet->neigh_node->if_incoming,
|
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nc_packet->nc_path->next_hop);
|
|
nc_packet->skb = NULL;
|
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batadv_nc_packet_free(nc_packet);
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_fwd_flush - Checks the timestamp of the given nc packet.
|
|
* @bat_priv: the bat priv with all the soft interface information
|
|
* @nc_path: the nc path the packet belongs to
|
|
* @nc_packet: the nc packet to be checked
|
|
*
|
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* Checks whether the given nc packet has hit its forward timeout. If so, the
|
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* packet is no longer delayed, immediately sent and the entry deleted from the
|
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* queue. Has to be called with the appropriate locks.
|
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*
|
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* Returns false as soon as the entry in the fifo queue has not been timed out
|
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* yet and true otherwise.
|
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*/
|
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static bool batadv_nc_fwd_flush(struct batadv_priv *bat_priv,
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struct batadv_nc_path *nc_path,
|
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struct batadv_nc_packet *nc_packet)
|
|
{
|
|
unsigned long timeout = bat_priv->nc.max_fwd_delay;
|
|
|
|
/* Packets are added to tail, so the remaining packets did not time
|
|
* out and we can stop processing the current queue
|
|
*/
|
|
if (atomic_read(&bat_priv->mesh_state) == BATADV_MESH_ACTIVE &&
|
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!batadv_has_timed_out(nc_packet->timestamp, timeout))
|
|
return false;
|
|
|
|
/* Send packet */
|
|
batadv_inc_counter(bat_priv, BATADV_CNT_FORWARD);
|
|
batadv_add_counter(bat_priv, BATADV_CNT_FORWARD_BYTES,
|
|
nc_packet->skb->len + ETH_HLEN);
|
|
list_del(&nc_packet->list);
|
|
batadv_nc_send_packet(nc_packet);
|
|
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_process_nc_paths - traverse given nc packet pool and free timed out
|
|
* nc packets
|
|
* @bat_priv: the bat priv with all the soft interface information
|
|
* @hash: to be processed hash table
|
|
* @process_fn: Function called to process given nc packet. Should return true
|
|
* to encourage this function to proceed with the next packet.
|
|
* Otherwise the rest of the current queue is skipped.
|
|
*/
|
|
static void
|
|
batadv_nc_process_nc_paths(struct batadv_priv *bat_priv,
|
|
struct batadv_hashtable *hash,
|
|
bool (*process_fn)(struct batadv_priv *,
|
|
struct batadv_nc_path *,
|
|
struct batadv_nc_packet *))
|
|
{
|
|
struct hlist_head *head;
|
|
struct batadv_nc_packet *nc_packet, *nc_packet_tmp;
|
|
struct batadv_nc_path *nc_path;
|
|
bool ret;
|
|
int i;
|
|
|
|
if (!hash)
|
|
return;
|
|
|
|
/* Loop hash table bins */
|
|
for (i = 0; i < hash->size; i++) {
|
|
head = &hash->table[i];
|
|
|
|
/* Loop coding paths */
|
|
rcu_read_lock();
|
|
hlist_for_each_entry_rcu(nc_path, head, hash_entry) {
|
|
/* Loop packets */
|
|
spin_lock_bh(&nc_path->packet_list_lock);
|
|
list_for_each_entry_safe(nc_packet, nc_packet_tmp,
|
|
&nc_path->packet_list, list) {
|
|
ret = process_fn(bat_priv, nc_path, nc_packet);
|
|
if (!ret)
|
|
break;
|
|
}
|
|
spin_unlock_bh(&nc_path->packet_list_lock);
|
|
}
|
|
rcu_read_unlock();
|
|
}
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_worker - periodic task for house keeping related to network coding
|
|
* @work: kernel work struct
|
|
*/
|
|
static void batadv_nc_worker(struct work_struct *work)
|
|
{
|
|
struct delayed_work *delayed_work;
|
|
struct batadv_priv_nc *priv_nc;
|
|
struct batadv_priv *bat_priv;
|
|
unsigned long timeout;
|
|
|
|
delayed_work = container_of(work, struct delayed_work, work);
|
|
priv_nc = container_of(delayed_work, struct batadv_priv_nc, work);
|
|
bat_priv = container_of(priv_nc, struct batadv_priv, nc);
|
|
|
|
batadv_nc_purge_orig_hash(bat_priv);
|
|
batadv_nc_purge_paths(bat_priv, bat_priv->nc.coding_hash,
|
|
batadv_nc_to_purge_nc_path_coding);
|
|
|
|
timeout = bat_priv->nc.max_fwd_delay;
|
|
|
|
if (batadv_has_timed_out(bat_priv->nc.timestamp_fwd_flush, timeout)) {
|
|
batadv_nc_process_nc_paths(bat_priv, bat_priv->nc.coding_hash,
|
|
batadv_nc_fwd_flush);
|
|
bat_priv->nc.timestamp_fwd_flush = jiffies;
|
|
}
|
|
|
|
/* Schedule a new check */
|
|
batadv_nc_start_timer(bat_priv);
|
|
}
|
|
|
|
/**
|
|
* batadv_can_nc_with_orig - checks whether the given orig node is suitable for
|
|
* coding or not
|
|
* @bat_priv: the bat priv with all the soft interface information
|
|
* @orig_node: neighboring orig node which may be used as nc candidate
|
|
* @ogm_packet: incoming ogm packet also used for the checks
|
|
*
|
|
* Returns true if:
|
|
* 1) The OGM must have the most recent sequence number.
|
|
* 2) The TTL must be decremented by one and only one.
|
|
* 3) The OGM must be received from the first hop from orig_node.
|
|
* 4) The TQ value of the OGM must be above bat_priv->nc.min_tq.
|
|
*/
|
|
static bool batadv_can_nc_with_orig(struct batadv_priv *bat_priv,
|
|
struct batadv_orig_node *orig_node,
|
|
struct batadv_ogm_packet *ogm_packet)
|
|
{
|
|
if (orig_node->last_real_seqno != ogm_packet->seqno)
|
|
return false;
|
|
if (orig_node->last_ttl != ogm_packet->header.ttl + 1)
|
|
return false;
|
|
if (!batadv_compare_eth(ogm_packet->orig, ogm_packet->prev_sender))
|
|
return false;
|
|
if (ogm_packet->tq < bat_priv->nc.min_tq)
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_find_nc_node - search for an existing nc node and return it
|
|
* @orig_node: orig node originating the ogm packet
|
|
* @orig_neigh_node: neighboring orig node from which we received the ogm packet
|
|
* (can be equal to orig_node)
|
|
* @in_coding: traverse incoming or outgoing network coding list
|
|
*
|
|
* Returns the nc_node if found, NULL otherwise.
|
|
*/
|
|
static struct batadv_nc_node
|
|
*batadv_nc_find_nc_node(struct batadv_orig_node *orig_node,
|
|
struct batadv_orig_node *orig_neigh_node,
|
|
bool in_coding)
|
|
{
|
|
struct batadv_nc_node *nc_node, *nc_node_out = NULL;
|
|
struct list_head *list;
|
|
|
|
if (in_coding)
|
|
list = &orig_neigh_node->in_coding_list;
|
|
else
|
|
list = &orig_neigh_node->out_coding_list;
|
|
|
|
/* Traverse list of nc_nodes to orig_node */
|
|
rcu_read_lock();
|
|
list_for_each_entry_rcu(nc_node, list, list) {
|
|
if (!batadv_compare_eth(nc_node->addr, orig_node->orig))
|
|
continue;
|
|
|
|
if (!atomic_inc_not_zero(&nc_node->refcount))
|
|
continue;
|
|
|
|
/* Found a match */
|
|
nc_node_out = nc_node;
|
|
break;
|
|
}
|
|
rcu_read_unlock();
|
|
|
|
return nc_node_out;
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_get_nc_node - retrieves an nc node or creates the entry if it was
|
|
* not found
|
|
* @bat_priv: the bat priv with all the soft interface information
|
|
* @orig_node: orig node originating the ogm packet
|
|
* @orig_neigh_node: neighboring orig node from which we received the ogm packet
|
|
* (can be equal to orig_node)
|
|
* @in_coding: traverse incoming or outgoing network coding list
|
|
*
|
|
* Returns the nc_node if found or created, NULL in case of an error.
|
|
*/
|
|
static struct batadv_nc_node
|
|
*batadv_nc_get_nc_node(struct batadv_priv *bat_priv,
|
|
struct batadv_orig_node *orig_node,
|
|
struct batadv_orig_node *orig_neigh_node,
|
|
bool in_coding)
|
|
{
|
|
struct batadv_nc_node *nc_node;
|
|
spinlock_t *lock; /* Used to lock list selected by "int in_coding" */
|
|
struct list_head *list;
|
|
|
|
/* Check if nc_node is already added */
|
|
nc_node = batadv_nc_find_nc_node(orig_node, orig_neigh_node, in_coding);
|
|
|
|
/* Node found */
|
|
if (nc_node)
|
|
return nc_node;
|
|
|
|
nc_node = kzalloc(sizeof(*nc_node), GFP_ATOMIC);
|
|
if (!nc_node)
|
|
return NULL;
|
|
|
|
if (!atomic_inc_not_zero(&orig_neigh_node->refcount))
|
|
goto free;
|
|
|
|
/* Initialize nc_node */
|
|
INIT_LIST_HEAD(&nc_node->list);
|
|
memcpy(nc_node->addr, orig_node->orig, ETH_ALEN);
|
|
nc_node->orig_node = orig_neigh_node;
|
|
atomic_set(&nc_node->refcount, 2);
|
|
|
|
/* Select ingoing or outgoing coding node */
|
|
if (in_coding) {
|
|
lock = &orig_neigh_node->in_coding_list_lock;
|
|
list = &orig_neigh_node->in_coding_list;
|
|
} else {
|
|
lock = &orig_neigh_node->out_coding_list_lock;
|
|
list = &orig_neigh_node->out_coding_list;
|
|
}
|
|
|
|
batadv_dbg(BATADV_DBG_NC, bat_priv, "Adding nc_node %pM -> %pM\n",
|
|
nc_node->addr, nc_node->orig_node->orig);
|
|
|
|
/* Add nc_node to orig_node */
|
|
spin_lock_bh(lock);
|
|
list_add_tail_rcu(&nc_node->list, list);
|
|
spin_unlock_bh(lock);
|
|
|
|
return nc_node;
|
|
|
|
free:
|
|
kfree(nc_node);
|
|
return NULL;
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_update_nc_node - updates stored incoming and outgoing nc node structs
|
|
* (best called on incoming OGMs)
|
|
* @bat_priv: the bat priv with all the soft interface information
|
|
* @orig_node: orig node originating the ogm packet
|
|
* @orig_neigh_node: neighboring orig node from which we received the ogm packet
|
|
* (can be equal to orig_node)
|
|
* @ogm_packet: incoming ogm packet
|
|
* @is_single_hop_neigh: orig_node is a single hop neighbor
|
|
*/
|
|
void batadv_nc_update_nc_node(struct batadv_priv *bat_priv,
|
|
struct batadv_orig_node *orig_node,
|
|
struct batadv_orig_node *orig_neigh_node,
|
|
struct batadv_ogm_packet *ogm_packet,
|
|
int is_single_hop_neigh)
|
|
{
|
|
struct batadv_nc_node *in_nc_node = NULL, *out_nc_node = NULL;
|
|
|
|
/* Check if network coding is enabled */
|
|
if (!atomic_read(&bat_priv->network_coding))
|
|
goto out;
|
|
|
|
/* accept ogms from 'good' neighbors and single hop neighbors */
|
|
if (!batadv_can_nc_with_orig(bat_priv, orig_node, ogm_packet) &&
|
|
!is_single_hop_neigh)
|
|
goto out;
|
|
|
|
/* Add orig_node as in_nc_node on hop */
|
|
in_nc_node = batadv_nc_get_nc_node(bat_priv, orig_node,
|
|
orig_neigh_node, true);
|
|
if (!in_nc_node)
|
|
goto out;
|
|
|
|
in_nc_node->last_seen = jiffies;
|
|
|
|
/* Add hop as out_nc_node on orig_node */
|
|
out_nc_node = batadv_nc_get_nc_node(bat_priv, orig_neigh_node,
|
|
orig_node, false);
|
|
if (!out_nc_node)
|
|
goto out;
|
|
|
|
out_nc_node->last_seen = jiffies;
|
|
|
|
out:
|
|
if (in_nc_node)
|
|
batadv_nc_node_free_ref(in_nc_node);
|
|
if (out_nc_node)
|
|
batadv_nc_node_free_ref(out_nc_node);
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_get_path - get existing nc_path or allocate a new one
|
|
* @bat_priv: the bat priv with all the soft interface information
|
|
* @hash: hash table containing the nc path
|
|
* @src: ethernet source address - first half of the nc path search key
|
|
* @dst: ethernet destination address - second half of the nc path search key
|
|
*
|
|
* Returns pointer to nc_path if the path was found or created, returns NULL
|
|
* on error.
|
|
*/
|
|
static struct batadv_nc_path *batadv_nc_get_path(struct batadv_priv *bat_priv,
|
|
struct batadv_hashtable *hash,
|
|
uint8_t *src,
|
|
uint8_t *dst)
|
|
{
|
|
int hash_added;
|
|
struct batadv_nc_path *nc_path, nc_path_key;
|
|
|
|
batadv_nc_hash_key_gen(&nc_path_key, src, dst);
|
|
|
|
/* Search for existing nc_path */
|
|
nc_path = batadv_nc_hash_find(hash, (void *)&nc_path_key);
|
|
|
|
if (nc_path) {
|
|
/* Set timestamp to delay removal of nc_path */
|
|
nc_path->last_valid = jiffies;
|
|
return nc_path;
|
|
}
|
|
|
|
/* No existing nc_path was found; create a new */
|
|
nc_path = kzalloc(sizeof(*nc_path), GFP_ATOMIC);
|
|
|
|
if (!nc_path)
|
|
return NULL;
|
|
|
|
/* Initialize nc_path */
|
|
INIT_LIST_HEAD(&nc_path->packet_list);
|
|
spin_lock_init(&nc_path->packet_list_lock);
|
|
atomic_set(&nc_path->refcount, 2);
|
|
nc_path->last_valid = jiffies;
|
|
memcpy(nc_path->next_hop, dst, ETH_ALEN);
|
|
memcpy(nc_path->prev_hop, src, ETH_ALEN);
|
|
|
|
batadv_dbg(BATADV_DBG_NC, bat_priv, "Adding nc_path %pM -> %pM\n",
|
|
nc_path->prev_hop,
|
|
nc_path->next_hop);
|
|
|
|
/* Add nc_path to hash table */
|
|
hash_added = batadv_hash_add(hash, batadv_nc_hash_compare,
|
|
batadv_nc_hash_choose, &nc_path_key,
|
|
&nc_path->hash_entry);
|
|
|
|
if (hash_added < 0) {
|
|
kfree(nc_path);
|
|
return NULL;
|
|
}
|
|
|
|
return nc_path;
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_skb_add_to_path - buffer skb for later encoding / decoding
|
|
* @skb: skb to add to path
|
|
* @nc_path: path to add skb to
|
|
* @neigh_node: next hop to forward packet to
|
|
* @packet_id: checksum to identify packet
|
|
*
|
|
* Returns true if the packet was buffered or false in case of an error.
|
|
*/
|
|
static bool batadv_nc_skb_add_to_path(struct sk_buff *skb,
|
|
struct batadv_nc_path *nc_path,
|
|
struct batadv_neigh_node *neigh_node,
|
|
__be32 packet_id)
|
|
{
|
|
struct batadv_nc_packet *nc_packet;
|
|
|
|
nc_packet = kzalloc(sizeof(*nc_packet), GFP_ATOMIC);
|
|
if (!nc_packet)
|
|
return false;
|
|
|
|
/* Initialize nc_packet */
|
|
nc_packet->timestamp = jiffies;
|
|
nc_packet->packet_id = packet_id;
|
|
nc_packet->skb = skb;
|
|
nc_packet->neigh_node = neigh_node;
|
|
nc_packet->nc_path = nc_path;
|
|
|
|
/* Add coding packet to list */
|
|
spin_lock_bh(&nc_path->packet_list_lock);
|
|
list_add_tail(&nc_packet->list, &nc_path->packet_list);
|
|
spin_unlock_bh(&nc_path->packet_list_lock);
|
|
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_skb_forward - try to code a packet or add it to the coding packet
|
|
* buffer
|
|
* @skb: data skb to forward
|
|
* @neigh_node: next hop to forward packet to
|
|
* @ethhdr: pointer to the ethernet header inside the skb
|
|
*
|
|
* Returns true if the skb was consumed (encoded packet sent) or false otherwise
|
|
*/
|
|
bool batadv_nc_skb_forward(struct sk_buff *skb,
|
|
struct batadv_neigh_node *neigh_node,
|
|
struct ethhdr *ethhdr)
|
|
{
|
|
const struct net_device *netdev = neigh_node->if_incoming->soft_iface;
|
|
struct batadv_priv *bat_priv = netdev_priv(netdev);
|
|
struct batadv_unicast_packet *packet;
|
|
struct batadv_nc_path *nc_path;
|
|
__be32 packet_id;
|
|
u8 *payload;
|
|
|
|
/* Check if network coding is enabled */
|
|
if (!atomic_read(&bat_priv->network_coding))
|
|
goto out;
|
|
|
|
/* We only handle unicast packets */
|
|
payload = skb_network_header(skb);
|
|
packet = (struct batadv_unicast_packet *)payload;
|
|
if (packet->header.packet_type != BATADV_UNICAST)
|
|
goto out;
|
|
|
|
/* Find or create a nc_path for this src-dst pair */
|
|
nc_path = batadv_nc_get_path(bat_priv,
|
|
bat_priv->nc.coding_hash,
|
|
ethhdr->h_source,
|
|
neigh_node->addr);
|
|
|
|
if (!nc_path)
|
|
goto out;
|
|
|
|
/* Add skb to nc_path */
|
|
packet_id = batadv_skb_crc32(skb, payload + sizeof(*packet));
|
|
if (!batadv_nc_skb_add_to_path(skb, nc_path, neigh_node, packet_id))
|
|
goto free_nc_path;
|
|
|
|
/* Packet is consumed */
|
|
return true;
|
|
|
|
free_nc_path:
|
|
batadv_nc_path_free_ref(nc_path);
|
|
out:
|
|
/* Packet is not consumed */
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_free - clean up network coding memory
|
|
* @bat_priv: the bat priv with all the soft interface information
|
|
*/
|
|
void batadv_nc_free(struct batadv_priv *bat_priv)
|
|
{
|
|
cancel_delayed_work_sync(&bat_priv->nc.work);
|
|
batadv_nc_purge_paths(bat_priv, bat_priv->nc.coding_hash, NULL);
|
|
batadv_hash_destroy(bat_priv->nc.coding_hash);
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_nodes_seq_print_text - print the nc node information
|
|
* @seq: seq file to print on
|
|
* @offset: not used
|
|
*/
|
|
int batadv_nc_nodes_seq_print_text(struct seq_file *seq, void *offset)
|
|
{
|
|
struct net_device *net_dev = (struct net_device *)seq->private;
|
|
struct batadv_priv *bat_priv = netdev_priv(net_dev);
|
|
struct batadv_hashtable *hash = bat_priv->orig_hash;
|
|
struct batadv_hard_iface *primary_if;
|
|
struct hlist_head *head;
|
|
struct batadv_orig_node *orig_node;
|
|
struct batadv_nc_node *nc_node;
|
|
int i;
|
|
|
|
primary_if = batadv_seq_print_text_primary_if_get(seq);
|
|
if (!primary_if)
|
|
goto out;
|
|
|
|
/* Traverse list of originators */
|
|
for (i = 0; i < hash->size; i++) {
|
|
head = &hash->table[i];
|
|
|
|
/* For each orig_node in this bin */
|
|
rcu_read_lock();
|
|
hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
|
|
seq_printf(seq, "Node: %pM\n", orig_node->orig);
|
|
|
|
seq_printf(seq, " Ingoing: ");
|
|
/* For each in_nc_node to this orig_node */
|
|
list_for_each_entry_rcu(nc_node,
|
|
&orig_node->in_coding_list,
|
|
list)
|
|
seq_printf(seq, "%pM ",
|
|
nc_node->addr);
|
|
seq_printf(seq, "\n");
|
|
|
|
seq_printf(seq, " Outgoing: ");
|
|
/* For out_nc_node to this orig_node */
|
|
list_for_each_entry_rcu(nc_node,
|
|
&orig_node->out_coding_list,
|
|
list)
|
|
seq_printf(seq, "%pM ",
|
|
nc_node->addr);
|
|
seq_printf(seq, "\n\n");
|
|
}
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
out:
|
|
if (primary_if)
|
|
batadv_hardif_free_ref(primary_if);
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* batadv_nc_init_debugfs - create nc folder and related files in debugfs
|
|
* @bat_priv: the bat priv with all the soft interface information
|
|
*/
|
|
int batadv_nc_init_debugfs(struct batadv_priv *bat_priv)
|
|
{
|
|
struct dentry *nc_dir, *file;
|
|
|
|
nc_dir = debugfs_create_dir("nc", bat_priv->debug_dir);
|
|
if (!nc_dir)
|
|
goto out;
|
|
|
|
file = debugfs_create_u8("min_tq", S_IRUGO | S_IWUSR, nc_dir,
|
|
&bat_priv->nc.min_tq);
|
|
if (!file)
|
|
goto out;
|
|
|
|
file = debugfs_create_u32("max_fwd_delay", S_IRUGO | S_IWUSR, nc_dir,
|
|
&bat_priv->nc.max_fwd_delay);
|
|
if (!file)
|
|
goto out;
|
|
|
|
return 0;
|
|
|
|
out:
|
|
return -ENOMEM;
|
|
}
|