cregit-Linux how code gets into the kernel

Release 4.11 net/batman-adv/network-coding.c

Directory: net/batman-adv
/* Copyright (C) 2012-2017  B.A.T.M.A.N. contributors:
 *
 * Martin Hundebøll, Jeppe Ledet-Pedersen
 *
 * 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 "network-coding.h"
#include "main.h"

#include <linux/atomic.h>
#include <linux/bitops.h>
#include <linux/byteorder/generic.h>
#include <linux/compiler.h>
#include <linux/debugfs.h>
#include <linux/errno.h>
#include <linux/etherdevice.h>
#include <linux/fs.h>
#include <linux/if_ether.h>
#include <linux/if_packet.h>
#include <linux/init.h>
#include <linux/jhash.h>
#include <linux/jiffies.h>
#include <linux/kernel.h>
#include <linux/kref.h>
#include <linux/list.h>
#include <linux/lockdep.h>
#include <linux/netdevice.h>
#include <linux/printk.h>
#include <linux/random.h>
#include <linux/rculist.h>
#include <linux/rcupdate.h>
#include <linux/seq_file.h>
#include <linux/skbuff.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/stddef.h>
#include <linux/string.h>
#include <linux/workqueue.h>

#include "hard-interface.h"
#include "hash.h"
#include "log.h"
#include "originator.h"
#include "packet.h"
#include "routing.h"
#include "send.h"
#include "tvlv.h"


static struct lock_class_key batadv_nc_coding_hash_lock_class_key;

static struct lock_class_key batadv_nc_decoding_hash_lock_class_key;

static void batadv_nc_worker(struct work_struct *work);
static int batadv_nc_recv_coded_packet(struct sk_buff *skb,
				       struct batadv_hard_iface *recv_if);

/**
 * batadv_nc_init - one-time initialization for network coding
 *
 * Return: 0 on success or negative error number in case of failure
 */



int __init batadv_nc_init(void)
{
	int ret;

	/* Register our packet type */
	ret = batadv_recv_handler_register(BATADV_CODED,
					   batadv_nc_recv_coded_packet);

	return ret;
}


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Matthias Schiffer24100.00%1100.00%


Total24100.00%1100.00%



/**
 * batadv_nc_start_timer - initialise the nc periodic worker
 * @bat_priv: the bat priv with all the soft interface information
 */



static void batadv_nc_start_timer(struct batadv_priv *bat_priv)
{
	queue_delayed_work(batadv_event_workqueue, &bat_priv->nc.work,
			   msecs_to_jiffies(10));
}


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Martin Hundeböll28100.00%1100.00%


Total28100.00%1100.00%



/**
 * batadv_nc_tvlv_container_update - update the network coding tvlv container
 *  after network coding setting change
 * @bat_priv: the bat priv with all the soft interface information
 */



static void batadv_nc_tvlv_container_update(struct batadv_priv *bat_priv)
{
	char nc_mode;

	nc_mode = atomic_read(&bat_priv->network_coding);

	switch (nc_mode) {
	case 0:
		batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_NC, 1);
		break;
	case 1:
		batadv_tvlv_container_register(bat_priv, BATADV_TVLV_NC, 1,
					       NULL, 0);
		break;
	}
}


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Marek Lindner60100.00%1100.00%


Total60100.00%1100.00%



/**
 * batadv_nc_status_update - update the network coding tvlv container after
 *  network coding setting change
 * @net_dev: the soft interface net device
 */



void batadv_nc_status_update(struct net_device *net_dev)
{
	struct batadv_priv *bat_priv = netdev_priv(net_dev);

	batadv_nc_tvlv_container_update(bat_priv);
}


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Marek Lindner25100.00%1100.00%


Total25100.00%1100.00%



/**
 * batadv_nc_tvlv_ogm_handler_v1 - process incoming nc tvlv container
 * @bat_priv: the bat priv with all the soft interface information
 * @orig: the orig_node of the ogm
 * @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags)
 * @tvlv_value: tvlv buffer containing the gateway data
 * @tvlv_value_len: tvlv buffer length
 */



static void batadv_nc_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv,
					  struct batadv_orig_node *orig,
					  u8 flags,
					  void *tvlv_value, u16 tvlv_value_len)
{
	if (flags & BATADV_TVLV_HANDLER_OGM_CIFNOTFND)
		clear_bit(BATADV_ORIG_CAPA_HAS_NC, &orig->capabilities);
	else
		set_bit(BATADV_ORIG_CAPA_HAS_NC, &orig->capabilities);
}


Contributors
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Marek Lindner3973.58%133.33%


Linus Lüssing1222.64%133.33%


Sven Eckelmann23.77%133.33%


Total53100.00%3100.00%



/**
 * batadv_nc_mesh_init - initialise coding hash table and start house keeping
 * @bat_priv: the bat priv with all the soft interface information
 *
 * Return: 0 on success or negative error number in case of failure
 */



int batadv_nc_mesh_init(struct batadv_priv *bat_priv)
{
	bat_priv->nc.timestamp_fwd_flush = jiffies;
	bat_priv->nc.timestamp_sniffed_purge = jiffies;

	if (bat_priv->nc.coding_hash || bat_priv->nc.decoding_hash)
		return 0;

	bat_priv->nc.coding_hash = batadv_hash_new(128);
	if (!bat_priv->nc.coding_hash)
		goto err;

	batadv_hash_set_lock_class(bat_priv->nc.coding_hash,
				   &batadv_nc_coding_hash_lock_class_key);

	bat_priv->nc.decoding_hash = batadv_hash_new(128);
	if (!bat_priv->nc.decoding_hash)
		goto err;

	batadv_hash_set_lock_class(bat_priv->nc.decoding_hash,
				   &batadv_nc_decoding_hash_lock_class_key);

	INIT_DELAYED_WORK(&bat_priv->nc.work, batadv_nc_worker);
	batadv_nc_start_timer(bat_priv);

	batadv_tvlv_handler_register(bat_priv, batadv_nc_tvlv_ogm_handler_v1,
				     NULL, BATADV_TVLV_NC, 1,
				     BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
	batadv_nc_tvlv_container_update(bat_priv);
	return 0;

err:
	return -ENOMEM;
}


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Martin Hundeböll13886.79%466.67%


Marek Lindner2012.58%116.67%


Matthias Schiffer10.63%116.67%


Total159100.00%6100.00%



/**
 * batadv_nc_init_bat_priv - initialise the nc specific bat_priv variables
 * @bat_priv: the bat priv with all the soft interface information
 */



void batadv_nc_init_bat_priv(struct batadv_priv *bat_priv)
{
	atomic_set(&bat_priv->network_coding, 0);
	bat_priv->nc.min_tq = 200;
	bat_priv->nc.max_fwd_delay = 10;
	bat_priv->nc.max_buffer_time = 200;
}


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Martin Hundeböll4397.73%480.00%


Sven Eckelmann12.27%120.00%


Total44100.00%5100.00%



/**
 * batadv_nc_init_orig - initialise the nc fields of an orig_node
 * @orig_node: the orig_node which is going to be initialised
 */



void batadv_nc_init_orig(struct batadv_orig_node *orig_node)
{
	INIT_LIST_HEAD(&orig_node->in_coding_list);
	INIT_LIST_HEAD(&orig_node->out_coding_list);
	spin_lock_init(&orig_node->in_coding_list_lock);
	spin_lock_init(&orig_node->out_coding_list_lock);
}


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Martin Hundeböll42100.00%2100.00%


Total42100.00%2100.00%



/**
 * batadv_nc_node_release - release nc_node from lists and queue for free after
 *  rcu grace period
 * @ref: kref pointer of the nc_node
 */



static void batadv_nc_node_release(struct kref *ref)
{
	struct batadv_nc_node *nc_node;

	nc_node = container_of(ref, struct batadv_nc_node, refcount);

	batadv_orig_node_put(nc_node->orig_node);
	kfree_rcu(nc_node, rcu);
}


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Sven Eckelmann2661.90%360.00%


Martin Hundeböll1638.10%240.00%


Total42100.00%5100.00%



/**
 * batadv_nc_node_put - decrement the nc_node refcounter and possibly
 *  release it
 * @nc_node: nc_node to be free'd
 */



static void batadv_nc_node_put(struct batadv_nc_node *nc_node)
{
	kref_put(&nc_node->refcount, batadv_nc_node_release);
}


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Martin Hundeböll1780.95%240.00%


Sven Eckelmann419.05%360.00%


Total21100.00%5100.00%



/**
 * batadv_nc_path_release - release nc_path from lists and queue for free after
 *  rcu grace period
 * @ref: kref pointer of the nc_path
 */



static void batadv_nc_path_release(struct kref *ref)
{
	struct batadv_nc_path *nc_path;

	nc_path = container_of(ref, struct batadv_nc_path, refcount);

	kfree_rcu(nc_path, rcu);
}


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Sven Eckelmann35100.00%1100.00%


Total35100.00%1100.00%



/**
 * batadv_nc_path_put - decrement the nc_path refcounter and possibly
 *  release it
 * @nc_path: nc_path to be free'd
 */



static void batadv_nc_path_put(struct batadv_nc_path *nc_path)
{
	kref_put(&nc_path->refcount, batadv_nc_path_release);
}


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Martin Hundeböll1885.71%133.33%


Sven Eckelmann314.29%266.67%


Total21100.00%3100.00%



/**
 * batadv_nc_packet_free - frees nc packet
 * @nc_packet: the nc packet to free
 * @dropped: whether the packet is freed because is is dropped
 */



static void batadv_nc_packet_free(struct batadv_nc_packet *nc_packet,
				  bool dropped)
{
	if (dropped)
		kfree_skb(nc_packet->skb);
	else
		consume_skb(nc_packet->skb);

	batadv_nc_path_put(nc_packet->nc_path);
	kfree(nc_packet);
}


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Martin Hundeböll2964.44%133.33%


Sven Eckelmann1635.56%266.67%


Total45100.00%3100.00%



/**
 * batadv_nc_to_purge_nc_node - checks whether an nc node has to be purged
 * @bat_priv: the bat priv with all the soft interface information
 * @nc_node: the nc node to check
 *
 * Return: true if the entry has to be purged now, false otherwise
 */



static bool batadv_nc_to_purge_nc_node(struct batadv_priv *bat_priv,
				       struct batadv_nc_node *nc_node)
{
	if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
		return true;

	return batadv_has_timed_out(nc_node->last_seen, BATADV_NC_NODE_TIMEOUT);
}


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Martin Hundeböll41100.00%2100.00%


Total41100.00%2100.00%



/**
 * batadv_nc_to_purge_nc_path_coding - checks whether an nc path has timed out
 * @bat_priv: the bat priv with all the soft interface information
 * @nc_path: the nc path to check
 *
 * Return: true if the entry has to be purged now, false otherwise
 */



static bool batadv_nc_to_purge_nc_path_coding(struct batadv_priv *bat_priv,
					      struct batadv_nc_path *nc_path)
{
	if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
		return true;

	/* purge the path when no packets has been added for 10 times the
         * max_fwd_delay time
         */
	return batadv_has_timed_out(nc_path->last_valid,
				    bat_priv->nc.max_fwd_delay * 10);
}


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Martin Hundeböll48100.00%1100.00%


Total48100.00%1100.00%



/**
 * batadv_nc_to_purge_nc_path_decoding - checks whether an nc path has timed out
 * @bat_priv: the bat priv with all the soft interface information
 * @nc_path: the nc path to check
 *
 * Return: true if the entry has to be purged now, false otherwise
 */



static bool batadv_nc_to_purge_nc_path_decoding(struct batadv_priv *bat_priv,
						struct batadv_nc_path *nc_path)
{
	if (atomic_read(&bat_priv->mesh_state) != BATADV_MESH_ACTIVE)
		return true;

	/* purge the path when no packets has been added for 10 times the
         * max_buffer time
         */
	return batadv_has_timed_out(nc_path->last_valid,
				    bat_priv->nc.max_buffer_time * 10);
}


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Martin Hundeböll48100.00%1100.00%


Total48100.00%1100.00%



/**
 * batadv_nc_purge_orig_nc_nodes - go through list of nc nodes and purge stale
 *  entries
 * @bat_priv: the bat priv with all the soft interface information
 * @list: list of nc nodes
 * @lock: nc node list lock
 * @to_purge: function in charge to decide whether an entry has to be purged or
 *            not. This function takes the nc node as argument and has to return
 *            a boolean value: true if the entry has to be deleted, false
 *            otherwise
 */


static void

batadv_nc_purge_orig_nc_nodes(struct batadv_priv *bat_priv,
			      struct list_head *list,
			      spinlock_t *lock,
			      bool (*to_purge)(struct batadv_priv *,
					       struct batadv_nc_node *))
{
	struct batadv_nc_node *nc_node, *nc_node_tmp;

	/* For each nc_node in list */
	spin_lock_bh(lock);
	list_for_each_entry_safe(nc_node, nc_node_tmp, list, list) {
		/* if an helper function has been passed as parameter,
                 * ask it if the entry has to be purged or not
                 */
		if (to_purge && !to_purge(bat_priv, nc_node))
			continue;

		batadv_dbg(BATADV_DBG_NC, bat_priv,
			   "Removing nc_node %pM -> %pM\n",
			   nc_node->addr, nc_node->orig_node->orig);
		list_del_rcu(&nc_node->list);
		batadv_nc_node_put(nc_node);
	}
	spin_unlock_bh(lock);
}


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Martin Hundeböll11199.11%266.67%


Sven Eckelmann10.89%133.33%


Total112100.00%3100.00%



/**
 * batadv_nc_purge_orig - purges all nc node data attached of the given
 *  originator
 * @bat_priv: the bat priv with all the soft interface information
 * @orig_node: orig_node with the nc node entries to be purged
 * @to_purge: function in charge to decide whether an entry has to be purged or
 *            not. This function takes the nc node as argument and has to return
 *            a boolean value: true is the entry has to be deleted, false
 *            otherwise
 */



void batadv_nc_purge_orig(struct batadv_priv *bat_priv,
			  struct batadv_orig_node *orig_node,
			  bool (*to_purge)(struct batadv_priv *,
					   struct batadv_nc_node *))
{
	/* Check ingoing nc_node's of this orig_node */
	batadv_nc_purge_orig_nc_nodes(bat_priv, &orig_node->in_coding_list,
				      &orig_node->in_coding_list_lock,
				      to_purge);

	/* Check outgoing nc_node's of this orig_node */
	batadv_nc_purge_orig_nc_nodes(bat_priv, &orig_node->out_coding_list,
				      &orig_node->out_coding_list_lock,
				      to_purge);
}


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Martin Hundeböll66100.00%2100.00%


Total66100.00%2100.00%



/**
 * batadv_nc_purge_orig_hash - traverse entire originator hash to check if they
 *  have timed out nc nodes
 * @bat_priv: the bat priv with all the soft interface information
 */



static void batadv_nc_purge_orig_hash(struct batadv_priv *bat_priv)
{
	struct batadv_hashtable *hash = bat_priv->orig_hash;
	struct hlist_head *head;
	struct batadv_orig_node *orig_node;
	u32 i;

	if (!hash)
		return;

	/* For each orig_node */
	for (i = 0; i < hash->size; i++) {
		head = &hash->table[i];

		rcu_read_lock();
		hlist_for_each_entry_rcu(orig_node, head, hash_entry)
			batadv_nc_purge_orig(bat_priv, orig_node,
					     batadv_nc_to_purge_nc_node);
		rcu_read_unlock();
	}
}


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Martin Hundeböll8998.89%150.00%


Sven Eckelmann11.11%150.00%


Total90100.00%2100.00%



/**
 * batadv_nc_purge_paths - traverse all nc paths part of the hash and remove
 *  unused ones
 * @bat_priv: the bat priv with all the soft interface information
 * @hash: hash table containing the nc paths to check
 * @to_purge: function in charge to decide whether an entry has to be purged or
 *            not. This function takes the nc node as argument and has to return
 *            a boolean value: true is the entry has to be deleted, false
 *            otherwise
 */



static void batadv_nc_purge_paths(struct batadv_priv *bat_priv,
				  struct batadv_hashtable *hash,
				  bool (*to_purge)(struct batadv_priv *,
						   struct batadv_nc_path *))
{
	struct hlist_head *head;
	struct hlist_node *node_tmp;
	struct batadv_nc_path *nc_path;
	spinlock_t *lock; /* Protects lists in hash */
	u32 i;

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

		/* For each nc_path in this bin */
		spin_lock_bh(lock);
		hlist_for_each_entry_safe(nc_path, node_tmp, head, hash_entry) {
			/* if an helper function has been passed as parameter,
                         * ask it if the entry has to be purged or not
                         */
			if (to_purge && !to_purge(bat_priv, nc_path))
				continue;

			/* purging an non-empty nc_path should never happen, but
                         * is observed under high CPU load. Delay the purging
                         * until next iteration to allow the packet_list to be
                         * emptied first.
                         */
			if (!unlikely(list_empty(&nc_path->packet_list))) {
				net_ratelimited_function(printk,
							 KERN_WARNING
							 "Skipping free of non-empty nc_path (%pM -> %pM)!\n",
							 nc_path->prev_hop,
							 nc_path->next_hop);
				continue;
			}

			/* nc_path is unused, so remove it */
			batadv_dbg(BATADV_DBG_NC, bat_priv,
				   "Remove nc_path %pM -> %pM\n",
				   nc_path->prev_hop, nc_path->next_hop);
			hlist_del_rcu(&nc_path->hash_entry);
			batadv_nc_path_put(nc_path);
		}
		spin_unlock_bh(lock);
	}
}


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Martin Hundeböll19198.96%250.00%


Sven Eckelmann21.04%250.00%


Total193100.00%4100.00%



/**
 * batadv_nc_hash_key_gen - computes the nc_path hash key
 * @key: buffer to hold the final hash key
 * @src: source ethernet mac address going into the hash key
 * @dst: destination ethernet mac address going into the hash key
 */



static void batadv_nc_hash_key_gen(struct batadv_nc_path *key, const char *src,
				   const char *dst)
{
	memcpy(key->prev_hop, src, sizeof(key->prev_hop));
	memcpy(key->next_hop, dst, sizeof(key->next_hop));
}


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Martin Hundeböll53100.00%2100.00%


Total53100.00%2100.00%



/**
 * batadv_nc_hash_choose - compute the hash value for an nc path
 * @data: data to hash
 * @size: size of the hash table
 *
 * Return: the selected index in the hash table for the given data.
 */



static u32 batadv_nc_hash_choose(const void *data, u32 size)
{
	const struct batadv_nc_path *nc_path = data;
	u32 hash = 0;

	hash = jhash(&nc_path->prev_hop, sizeof(nc_path->prev_hop), hash);
	hash = jhash(&nc_path->next_hop, sizeof(nc_path->next_hop), hash);

	return hash % size;
}


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Martin Hundeböll6187.14%250.00%


Sven Eckelmann912.86%250.00%


Total70100.00%4100.00%



/**
 * batadv_nc_hash_compare - comparing function used in the network coding hash
 *  tables
 * @node: node in the local table
 * @data2: second object to compare the node to
 *
 * Return: true if the two entry are the same, false otherwise
 */



static bool batadv_nc_hash_compare(const struct hlist_node *node,
				   const void *data2)
{
	const struct batadv_nc_path *nc_path1, *nc_path2;

	nc_path1 = container_of(node, struct batadv_nc_path, hash_entry);
	nc_path2 = data2;

	/* Return 1 if the two keys are identical */
	if (!batadv_compare_eth(nc_path1->prev_hop, nc_path2->prev_hop))
		return false;

	if (!batadv_compare_eth(nc_path1->next_hop, nc_path2->next_hop))
		return false;

	return true;
}


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Martin Hundeböll7290.00%250.00%


Sven Eckelmann45.00%125.00%


Antonio Quartulli45.00%125.00%


Total80100.00%4100.00%



/**
 * batadv_nc_hash_find - search for an existing nc path and return it
 * @hash: hash table containing the nc path
 * @data: search key
 *
 * Return: the nc_path if found, NULL otherwise.
 */


static struct batadv_nc_path *

batadv_nc_hash_find(struct batadv_hashtable *hash,
		    void *data)
{
	struct hlist_head *head;
	struct batadv_nc_path *nc_path, *nc_path_tmp = NULL;
	int index;

	if (!hash)
		return NULL;

	index = batadv_nc_hash_choose(data, hash->size);
	head = &hash->table[index];

	rcu_read_lock();
	hlist_for_each_entry_rcu(nc_path, head, hash_entry) {
		if (!batadv_nc_hash_compare(&nc_path->hash_entry, data))
			continue;

		if (!kref_get_unless_zero(&nc_path->refcount))
			continue;

		nc_path_tmp = nc_path;
		break;
	}
	rcu_read_unlock();

	return nc_path_tmp;
}


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Martin Hundeböll11399.12%266.67%


Sven Eckelmann10.88%133.33%


Total114100.00%3100.00%



/**
 * batadv_nc_send_packet - send non-coded packet and free nc_packet struct
 * @nc_packet: the nc packet to send
 */



static void batadv_nc_send_packet(struct batadv_nc_packet *nc_packet)
{
	batadv_send_unicast_skb(nc_packet->skb, nc_packet->neigh_node);
	nc_packet->skb = NULL;
	batadv_nc_packet_free(nc_packet, false);
}


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Martin Hundeböll3291.43%133.33%


Sven Eckelmann25.71%133.33%


Antonio Quartulli12.86%133.33%


Total35100.00%3100.00%



/**
 * batadv_nc_sniffed_purge - Checks timestamp of given sniffed 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
 *
 * Checks whether the given sniffed (overheard) nc_packet has hit its buffering
 * timeout. If so, the packet is no longer kept and the entry deleted from the
 * queue. Has to be called with the appropriate locks.
 *
 * Return: false as soon as the entry in the fifo queue has not been timed out
 * yet and true otherwise.
 */



static bool batadv_nc_sniffed_purge(struct batadv_priv *bat_priv,
				    struct batadv_nc_path *nc_path,
				    struct batadv_nc_packet *nc_packet)
{
	unsigned long timeout = bat_priv->nc.max_buffer_time;
	bool res = false;

	lockdep_assert_held(&nc_path->packet_list_lock);

	/* 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 &&
	    !batadv_has_timed_out(nc_packet->timestamp, timeout))
		goto out;

	/* purge nc packet */
	list_del(&nc_packet->list);
	batadv_nc_packet_free(nc_packet, true);

	res = true;

out:
	return res;
}


Contributors
PersonTokensPropCommitsCommitProp
Martin Hundeböll8589.47%133.33%


Sven Eckelmann1010.53%266.67%


Total95100.00%3100.00%



/**
 * 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
 *
 * Checks whether the given nc packet has hit its forward timeout. If so, the
 * packet is no longer delayed, immediately sent and the entry deleted from the
 * queue. Has to be called with the appropriate locks.
 *
 * Return: false as soon as the entry in the fifo queue has not been timed out
 * yet and true otherwise.
 */



static bool batadv_nc_fwd_flush(struct batadv_priv *bat_priv,
				struct batadv_nc_path *nc_path,
				struct batadv_nc_packet *nc_packet)
{
	unsigned long timeout = bat_priv->nc.max_fwd_delay;

	lockdep_assert_held(&nc_path->packet_list_lock);

	/* 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 &&
	    !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;
}


Contributors
PersonTokensPropCommitsCommitProp
Martin Hundeböll9692.31%150.00%


Sven Eckelmann87.69%150.00%


Total104100.00%2100.00%



/**
 * 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();
	}
}


Contributors
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Martin Hundeböll156100.00%1100.00%


Total156100.00%1100.00%



/**
 * 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 = to_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);
	batadv_nc_purge_paths(bat_priv, bat_priv->nc.decoding_hash,
			      batadv_nc_to_purge_nc_path_decoding);

	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;
	}

	if (batadv_has_timed_out(bat_priv->nc.timestamp_sniffed_purge,
				 bat_priv->nc.max_buffer_time)) {
		batadv_nc_process_nc_paths(bat_priv, bat_priv->nc.decoding_hash,
					   batadv_nc_sniffed_purge);
		bat_priv->nc.timestamp_sniffed_purge = jiffies;
	}

	/* Schedule a new check */
	batadv_nc_start_timer(bat_priv);
}


Contributors
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Martin Hundeböll18199.45%266.67%


Geliang Tang10.55%133.33%


Total182100.00%3100.00%



/**
 * 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
 *
 * Return: 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)
{
	struct batadv_orig_ifinfo *orig_ifinfo;
	u32 last_real_seqno;
	u8 last_ttl;

	orig_ifinfo = batadv_orig_ifinfo_get(orig_node, BATADV_IF_DEFAULT);
	if (!orig_ifinfo)
		return false;

	last_ttl = orig_ifinfo->last_ttl;
	last_real_seqno = orig_ifinfo->last_real_seqno;
	batadv_orig_ifinfo_put(orig_ifinfo);

	if (last_real_seqno != ntohl(ogm_packet->seqno))
		return false;
	if (last_ttl != ogm_packet->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;
}


Contributors
PersonTokensPropCommitsCommitProp
Martin Hundeböll8465.62%240.00%


Simon Wunderlich4132.03%120.00%


Sven Eckelmann32.34%240.00%


Total128100.00%5100.00%



/**
 * 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
 *
 * Return: 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 (!kref_get_unless_zero(&nc_node->refcount))
			continue;

		/* Found a match */
		nc_node_out = nc_node;
		break;
	}
	rcu_read_unlock();

	return nc_node_out;
}


Contributors
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Martin Hundeböll10799.07%150.00%


Sven Eckelmann10.93%150.00%


Total108100.00%2100.00%



/**
 * 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
 *
 * Return: 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;

	/* Initialize nc_node */
	INIT_LIST_HEAD(&nc_node->list);
	kref_init(&nc_node->refcount);
	ether_addr_copy(nc_node->addr, orig_node->orig);
	kref_get(&orig_neigh_node->refcount);
	nc_node->orig_node = orig_neigh_node;

	/* 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);
	kref_get(&nc_node->refcount);
	list_add_tail_rcu(&nc_node->list, list);
	spin_unlock_bh(lock);

	return nc_node;
}


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Martin Hundeböll18184.98%116.67%


Sven Eckelmann3114.55%466.67%


Antonio Quartulli10.47%116.67%


Total213100.00%6100.00%



/**
 * 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;
	struct batadv_nc_node *out_nc_node = NULL;

	/* Check if network coding is enabled */
	if (!atomic_read(&bat_priv->network_coding