Initial file dump from open source releaseHEADmaster

1 files changed, 666 insertions, 0 deletions

diff --git a/net/batman-adv/originator.c b/net/batman-adv/originator.c
new file mode 100644
index 00000000..fad1a209
--- /dev/null
+++ b/net/batman-adv/originator.c
@@ -0,0 +1,666 @@
+/* Copyright (C) 2009-2013 B.A.T.M.A.N. contributors:
+ *
+ * Marek Lindner, Simon Wunderlich
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA
+ */
+
+#include "main.h"
+#include "distributed-arp-table.h"
+#include "originator.h"
+#include "hash.h"
+#include "translation-table.h"
+#include "routing.h"
+#include "gateway_client.h"
+#include "hard-interface.h"
+#include "unicast.h"
+#include "soft-interface.h"
+#include "bridge_loop_avoidance.h"
+#include "network-coding.h"
+
+/* hash class keys */
+static struct lock_class_key batadv_orig_hash_lock_class_key;
+
+static void batadv_purge_orig(struct work_struct *work);
+
+/* returns 1 if they are the same originator */
+static int batadv_compare_orig(const struct hlist_node *node, const void *data2)
+{
+	const void *data1 = container_of(node, struct batadv_orig_node,
+					 hash_entry);
+
+	return (memcmp(data1, data2, ETH_ALEN) == 0 ? 1 : 0);
+}
+
+int batadv_originator_init(struct batadv_priv *bat_priv)
+{
+	if (bat_priv->orig_hash)
+		return 0;
+
+	bat_priv->orig_hash = batadv_hash_new(1024);
+
+	if (!bat_priv->orig_hash)
+		goto err;
+
+	batadv_hash_set_lock_class(bat_priv->orig_hash,
+				   &batadv_orig_hash_lock_class_key);
+
+	INIT_DELAYED_WORK(&bat_priv->orig_work, batadv_purge_orig);
+	queue_delayed_work(batadv_event_workqueue,
+			   &bat_priv->orig_work,
+			   msecs_to_jiffies(BATADV_ORIG_WORK_PERIOD));
+
+	return 0;
+
+err:
+	return -ENOMEM;
+}
+
+void batadv_neigh_node_free_ref(struct batadv_neigh_node *neigh_node)
+{
+	if (atomic_dec_and_test(&neigh_node->refcount))
+		kfree_rcu(neigh_node, rcu);
+}
+
+/* increases the refcounter of a found router */
+struct batadv_neigh_node *
+batadv_orig_node_get_router(struct batadv_orig_node *orig_node)
+{
+	struct batadv_neigh_node *router;
+
+	rcu_read_lock();
+	router = rcu_dereference(orig_node->router);
+
+	if (router && !atomic_inc_not_zero(&router->refcount))
+		router = NULL;
+
+	rcu_read_unlock();
+	return router;
+}
+
+struct batadv_neigh_node *
+batadv_neigh_node_new(struct batadv_hard_iface *hard_iface,
+		      const uint8_t *neigh_addr, uint32_t seqno)
+{
+	struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
+	struct batadv_neigh_node *neigh_node;
+
+	neigh_node = kzalloc(sizeof(*neigh_node), GFP_ATOMIC);
+	if (!neigh_node)
+		goto out;
+
+	INIT_HLIST_NODE(&neigh_node->list);
+
+	memcpy(neigh_node->addr, neigh_addr, ETH_ALEN);
+	spin_lock_init(&neigh_node->lq_update_lock);
+
+	/* extra reference for return */
+	atomic_set(&neigh_node->refcount, 2);
+
+	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
+		   "Creating new neighbor %pM, initial seqno %d\n",
+		   neigh_addr, seqno);
+
+out:
+	return neigh_node;
+}
+
+static void batadv_orig_node_free_rcu(struct rcu_head *rcu)
+{
+	struct hlist_node *node_tmp;
+	struct batadv_neigh_node *neigh_node, *tmp_neigh_node;
+	struct batadv_orig_node *orig_node;
+
+	orig_node = container_of(rcu, struct batadv_orig_node, rcu);
+
+	spin_lock_bh(&orig_node->neigh_list_lock);
+
+	/* for all bonding members ... */
+	list_for_each_entry_safe(neigh_node, tmp_neigh_node,
+				 &orig_node->bond_list, bonding_list) {
+		list_del_rcu(&neigh_node->bonding_list);
+		batadv_neigh_node_free_ref(neigh_node);
+	}
+
+	/* for all neighbors towards this originator ... */
+	hlist_for_each_entry_safe(neigh_node, node_tmp,
+				  &orig_node->neigh_list, list) {
+		hlist_del_rcu(&neigh_node->list);
+		batadv_neigh_node_free_ref(neigh_node);
+	}
+
+	spin_unlock_bh(&orig_node->neigh_list_lock);
+
+	/* Free nc_nodes */
+	batadv_nc_purge_orig(orig_node->bat_priv, orig_node, NULL);
+
+	batadv_frag_list_free(&orig_node->frag_list);
+	batadv_tt_global_del_orig(orig_node->bat_priv, orig_node,
+				  "originator timed out");
+
+	kfree(orig_node->tt_buff);
+	kfree(orig_node->bcast_own);
+	kfree(orig_node->bcast_own_sum);
+	kfree(orig_node);
+}
+
+/**
+ * batadv_orig_node_free_ref - decrement the orig node refcounter and possibly
+ * schedule an rcu callback for freeing it
+ * @orig_node: the orig node to free
+ */
+void batadv_orig_node_free_ref(struct batadv_orig_node *orig_node)
+{
+	if (atomic_dec_and_test(&orig_node->refcount))
+		call_rcu(&orig_node->rcu, batadv_orig_node_free_rcu);
+}
+
+/**
+ * batadv_orig_node_free_ref_now - decrement the orig node refcounter and
+ * possibly free it (without rcu callback)
+ * @orig_node: the orig node to free
+ */
+void batadv_orig_node_free_ref_now(struct batadv_orig_node *orig_node)
+{
+	if (atomic_dec_and_test(&orig_node->refcount))
+		batadv_orig_node_free_rcu(&orig_node->rcu);
+}
+
+void batadv_originator_free(struct batadv_priv *bat_priv)
+{
+	struct batadv_hashtable *hash = bat_priv->orig_hash;
+	struct hlist_node *node_tmp;
+	struct hlist_head *head;
+	spinlock_t *list_lock; /* spinlock to protect write access */
+	struct batadv_orig_node *orig_node;
+	uint32_t i;
+
+	if (!hash)
+		return;
+
+	cancel_delayed_work_sync(&bat_priv->orig_work);
+
+	bat_priv->orig_hash = NULL;
+
+	for (i = 0; i < hash->size; i++) {
+		head = &hash->table[i];
+		list_lock = &hash->list_locks[i];
+
+		spin_lock_bh(list_lock);
+		hlist_for_each_entry_safe(orig_node, node_tmp,
+					  head, hash_entry) {
+			hlist_del_rcu(&orig_node->hash_entry);
+			batadv_orig_node_free_ref(orig_node);
+		}
+		spin_unlock_bh(list_lock);
+	}
+
+	batadv_hash_destroy(hash);
+}
+
+/* this function finds or creates an originator entry for the given
+ * address if it does not exits
+ */
+struct batadv_orig_node *batadv_get_orig_node(struct batadv_priv *bat_priv,
+					      const uint8_t *addr)
+{
+	struct batadv_orig_node *orig_node;
+	int size;
+	int hash_added;
+	unsigned long reset_time;
+
+	orig_node = batadv_orig_hash_find(bat_priv, addr);
+	if (orig_node)
+		return orig_node;
+
+	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
+		   "Creating new originator: %pM\n", addr);
+
+	orig_node = kzalloc(sizeof(*orig_node), GFP_ATOMIC);
+	if (!orig_node)
+		return NULL;
+
+	INIT_HLIST_HEAD(&orig_node->neigh_list);
+	INIT_LIST_HEAD(&orig_node->bond_list);
+	spin_lock_init(&orig_node->ogm_cnt_lock);
+	spin_lock_init(&orig_node->bcast_seqno_lock);
+	spin_lock_init(&orig_node->neigh_list_lock);
+	spin_lock_init(&orig_node->tt_buff_lock);
+
+	batadv_nc_init_orig(orig_node);
+
+	/* extra reference for return */
+	atomic_set(&orig_node->refcount, 2);
+
+	orig_node->tt_initialised = false;
+	orig_node->bat_priv = bat_priv;
+	memcpy(orig_node->orig, addr, ETH_ALEN);
+	batadv_dat_init_orig_node_addr(orig_node);
+	orig_node->router = NULL;
+	orig_node->tt_crc = 0;
+	atomic_set(&orig_node->last_ttvn, 0);
+	orig_node->tt_buff = NULL;
+	orig_node->tt_buff_len = 0;
+	atomic_set(&orig_node->tt_size, 0);
+	reset_time = jiffies - 1 - msecs_to_jiffies(BATADV_RESET_PROTECTION_MS);
+	orig_node->bcast_seqno_reset = reset_time;
+	orig_node->batman_seqno_reset = reset_time;
+
+	atomic_set(&orig_node->bond_candidates, 0);
+
+	size = bat_priv->num_ifaces * sizeof(unsigned long) * BATADV_NUM_WORDS;
+
+	orig_node->bcast_own = kzalloc(size, GFP_ATOMIC);
+	if (!orig_node->bcast_own)
+		goto free_orig_node;
+
+	size = bat_priv->num_ifaces * sizeof(uint8_t);
+	orig_node->bcast_own_sum = kzalloc(size, GFP_ATOMIC);
+
+	INIT_LIST_HEAD(&orig_node->frag_list);
+	orig_node->last_frag_packet = 0;
+
+	if (!orig_node->bcast_own_sum)
+		goto free_bcast_own;
+
+	hash_added = batadv_hash_add(bat_priv->orig_hash, batadv_compare_orig,
+				     batadv_choose_orig, orig_node,
+				     &orig_node->hash_entry);
+	if (hash_added != 0)
+		goto free_bcast_own_sum;
+
+	return orig_node;
+free_bcast_own_sum:
+	kfree(orig_node->bcast_own_sum);
+free_bcast_own:
+	kfree(orig_node->bcast_own);
+free_orig_node:
+	kfree(orig_node);
+	return NULL;
+}
+
+static bool
+batadv_purge_orig_neighbors(struct batadv_priv *bat_priv,
+			    struct batadv_orig_node *orig_node,
+			    struct batadv_neigh_node **best_neigh_node)
+{
+	struct hlist_node *node_tmp;
+	struct batadv_neigh_node *neigh_node;
+	bool neigh_purged = false;
+	unsigned long last_seen;
+	struct batadv_hard_iface *if_incoming;
+
+	*best_neigh_node = NULL;
+
+	spin_lock_bh(&orig_node->neigh_list_lock);
+
+	/* for all neighbors towards this originator ... */
+	hlist_for_each_entry_safe(neigh_node, node_tmp,
+				  &orig_node->neigh_list, list) {
+		last_seen = neigh_node->last_seen;
+		if_incoming = neigh_node->if_incoming;
+
+		if ((batadv_has_timed_out(last_seen, BATADV_PURGE_TIMEOUT)) ||
+		    (if_incoming->if_status == BATADV_IF_INACTIVE) ||
+		    (if_incoming->if_status == BATADV_IF_NOT_IN_USE) ||
+		    (if_incoming->if_status == BATADV_IF_TO_BE_REMOVED)) {
+			if ((if_incoming->if_status == BATADV_IF_INACTIVE) ||
+			    (if_incoming->if_status == BATADV_IF_NOT_IN_USE) ||
+			    (if_incoming->if_status == BATADV_IF_TO_BE_REMOVED))
+				batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
+					   "neighbor purge: originator %pM, neighbor: %pM, iface: %s\n",
+					   orig_node->orig, neigh_node->addr,
+					   if_incoming->net_dev->name);
+			else
+				batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
+					   "neighbor timeout: originator %pM, neighbor: %pM, last_seen: %u\n",
+					   orig_node->orig, neigh_node->addr,
+					   jiffies_to_msecs(last_seen));
+
+			neigh_purged = true;
+
+			hlist_del_rcu(&neigh_node->list);
+			batadv_bonding_candidate_del(orig_node, neigh_node);
+			batadv_neigh_node_free_ref(neigh_node);
+		} else {
+			if ((!*best_neigh_node) ||
+			    (neigh_node->tq_avg > (*best_neigh_node)->tq_avg))
+				*best_neigh_node = neigh_node;
+		}
+	}
+
+	spin_unlock_bh(&orig_node->neigh_list_lock);
+	return neigh_purged;
+}
+
+static bool batadv_purge_orig_node(struct batadv_priv *bat_priv,
+				   struct batadv_orig_node *orig_node)
+{
+	struct batadv_neigh_node *best_neigh_node;
+
+	if (batadv_has_timed_out(orig_node->last_seen,
+				 2 * BATADV_PURGE_TIMEOUT)) {
+		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
+			   "Originator timeout: originator %pM, last_seen %u\n",
+			   orig_node->orig,
+			   jiffies_to_msecs(orig_node->last_seen));
+		return true;
+	} else {
+		if (batadv_purge_orig_neighbors(bat_priv, orig_node,
+						&best_neigh_node))
+			batadv_update_route(bat_priv, orig_node,
+					    best_neigh_node);
+	}
+
+	return false;
+}
+
+static void _batadv_purge_orig(struct batadv_priv *bat_priv)
+{
+	struct batadv_hashtable *hash = bat_priv->orig_hash;
+	struct hlist_node *node_tmp;
+	struct hlist_head *head;
+	spinlock_t *list_lock; /* spinlock to protect write access */
+	struct batadv_orig_node *orig_node;
+	uint32_t i;
+
+	if (!hash)
+		return;
+
+	/* for all origins... */
+	for (i = 0; i < hash->size; i++) {
+		head = &hash->table[i];
+		list_lock = &hash->list_locks[i];
+
+		spin_lock_bh(list_lock);
+		hlist_for_each_entry_safe(orig_node, node_tmp,
+					  head, hash_entry) {
+			if (batadv_purge_orig_node(bat_priv, orig_node)) {
+				if (orig_node->gw_flags)
+					batadv_gw_node_delete(bat_priv,
+							      orig_node);
+				hlist_del_rcu(&orig_node->hash_entry);
+				batadv_orig_node_free_ref(orig_node);
+				continue;
+			}
+
+			if (batadv_has_timed_out(orig_node->last_frag_packet,
+						 BATADV_FRAG_TIMEOUT))
+				batadv_frag_list_free(&orig_node->frag_list);
+		}
+		spin_unlock_bh(list_lock);
+	}
+
+	batadv_gw_node_purge(bat_priv);
+	batadv_gw_election(bat_priv);
+}
+
+static void batadv_purge_orig(struct work_struct *work)
+{
+	struct delayed_work *delayed_work;
+	struct batadv_priv *bat_priv;
+
+	delayed_work = container_of(work, struct delayed_work, work);
+	bat_priv = container_of(delayed_work, struct batadv_priv, orig_work);
+	_batadv_purge_orig(bat_priv);
+	queue_delayed_work(batadv_event_workqueue,
+			   &bat_priv->orig_work,
+			   msecs_to_jiffies(BATADV_ORIG_WORK_PERIOD));
+}
+
+void batadv_purge_orig_ref(struct batadv_priv *bat_priv)
+{
+	_batadv_purge_orig(bat_priv);
+}
+
+int batadv_orig_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 hlist_head *head;
+	struct batadv_hard_iface *primary_if;
+	struct batadv_orig_node *orig_node;
+	struct batadv_neigh_node *neigh_node, *neigh_node_tmp;
+	int batman_count = 0;
+	int last_seen_secs;
+	int last_seen_msecs;
+	unsigned long last_seen_jiffies;
+	uint32_t i;
+
+	primary_if = batadv_seq_print_text_primary_if_get(seq);
+	if (!primary_if)
+		goto out;
+
+	seq_printf(seq, "[B.A.T.M.A.N. adv %s, MainIF/MAC: %s/%pM (%s)]\n",
+		   BATADV_SOURCE_VERSION, primary_if->net_dev->name,
+		   primary_if->net_dev->dev_addr, net_dev->name);
+	seq_printf(seq, "  %-15s %s (%s/%i) %17s [%10s]: %20s ...\n",
+		   "Originator", "last-seen", "#", BATADV_TQ_MAX_VALUE,
+		   "Nexthop", "outgoingIF", "Potential nexthops");
+
+	for (i = 0; i < hash->size; i++) {
+		head = &hash->table[i];
+
+		rcu_read_lock();
+		hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
+			neigh_node = batadv_orig_node_get_router(orig_node);
+			if (!neigh_node)
+				continue;
+
+			if (neigh_node->tq_avg == 0)
+				goto next;
+
+			last_seen_jiffies = jiffies - orig_node->last_seen;
+			last_seen_msecs = jiffies_to_msecs(last_seen_jiffies);
+			last_seen_secs = last_seen_msecs / 1000;
+			last_seen_msecs = last_seen_msecs % 1000;
+
+			seq_printf(seq, "%pM %4i.%03is   (%3i) %pM [%10s]:",
+				   orig_node->orig, last_seen_secs,
+				   last_seen_msecs, neigh_node->tq_avg,
+				   neigh_node->addr,
+				   neigh_node->if_incoming->net_dev->name);
+
+			hlist_for_each_entry_rcu(neigh_node_tmp,
+						 &orig_node->neigh_list, list) {
+				seq_printf(seq, " %pM (%3i)",
+					   neigh_node_tmp->addr,
+					   neigh_node_tmp->tq_avg);
+			}
+
+			seq_puts(seq, "\n");
+			batman_count++;
+
+next:
+			batadv_neigh_node_free_ref(neigh_node);
+		}
+		rcu_read_unlock();
+	}
+
+	if (batman_count == 0)
+		seq_puts(seq, "No batman nodes in range ...\n");
+
+out:
+	if (primary_if)
+		batadv_hardif_free_ref(primary_if);
+	return 0;
+}
+
+static int batadv_orig_node_add_if(struct batadv_orig_node *orig_node,
+				   int max_if_num)
+{
+	void *data_ptr;
+	size_t data_size, old_size;
+
+	data_size = max_if_num * sizeof(unsigned long) * BATADV_NUM_WORDS;
+	old_size = (max_if_num - 1) * sizeof(unsigned long) * BATADV_NUM_WORDS;
+	data_ptr = kmalloc(data_size, GFP_ATOMIC);
+	if (!data_ptr)
+		return -ENOMEM;
+
+	memcpy(data_ptr, orig_node->bcast_own, old_size);
+	kfree(orig_node->bcast_own);
+	orig_node->bcast_own = data_ptr;
+
+	data_ptr = kmalloc(max_if_num * sizeof(uint8_t), GFP_ATOMIC);
+	if (!data_ptr)
+		return -ENOMEM;
+
+	memcpy(data_ptr, orig_node->bcast_own_sum,
+	       (max_if_num - 1) * sizeof(uint8_t));
+	kfree(orig_node->bcast_own_sum);
+	orig_node->bcast_own_sum = data_ptr;
+
+	return 0;
+}
+
+int batadv_orig_hash_add_if(struct batadv_hard_iface *hard_iface,
+			    int max_if_num)
+{
+	struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
+	struct batadv_hashtable *hash = bat_priv->orig_hash;
+	struct hlist_head *head;
+	struct batadv_orig_node *orig_node;
+	uint32_t i;
+	int ret;
+
+	/* resize all orig nodes because orig_node->bcast_own(_sum) depend on
+	 * if_num
+	 */
+	for (i = 0; i < hash->size; i++) {
+		head = &hash->table[i];
+
+		rcu_read_lock();
+		hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
+			spin_lock_bh(&orig_node->ogm_cnt_lock);
+			ret = batadv_orig_node_add_if(orig_node, max_if_num);
+			spin_unlock_bh(&orig_node->ogm_cnt_lock);
+
+			if (ret == -ENOMEM)
+				goto err;
+		}
+		rcu_read_unlock();
+	}
+
+	return 0;
+
+err:
+	rcu_read_unlock();
+	return -ENOMEM;
+}
+
+static int batadv_orig_node_del_if(struct batadv_orig_node *orig_node,
+				   int max_if_num, int del_if_num)
+{
+	void *data_ptr = NULL;
+	int chunk_size;
+
+	/* last interface was removed */
+	if (max_if_num == 0)
+		goto free_bcast_own;
+
+	chunk_size = sizeof(unsigned long) * BATADV_NUM_WORDS;
+	data_ptr = kmalloc(max_if_num * chunk_size, GFP_ATOMIC);
+	if (!data_ptr)
+		return -ENOMEM;
+
+	/* copy first part */
+	memcpy(data_ptr, orig_node->bcast_own, del_if_num * chunk_size);
+
+	/* copy second part */
+	memcpy((char *)data_ptr + del_if_num * chunk_size,
+	       orig_node->bcast_own + ((del_if_num + 1) * chunk_size),
+	       (max_if_num - del_if_num) * chunk_size);
+
+free_bcast_own:
+	kfree(orig_node->bcast_own);
+	orig_node->bcast_own = data_ptr;
+
+	if (max_if_num == 0)
+		goto free_own_sum;
+
+	data_ptr = kmalloc(max_if_num * sizeof(uint8_t), GFP_ATOMIC);
+	if (!data_ptr)
+		return -ENOMEM;
+
+	memcpy(data_ptr, orig_node->bcast_own_sum,
+	       del_if_num * sizeof(uint8_t));
+
+	memcpy((char *)data_ptr + del_if_num * sizeof(uint8_t),
+	       orig_node->bcast_own_sum + ((del_if_num + 1) * sizeof(uint8_t)),
+	       (max_if_num - del_if_num) * sizeof(uint8_t));
+
+free_own_sum:
+	kfree(orig_node->bcast_own_sum);
+	orig_node->bcast_own_sum = data_ptr;
+
+	return 0;
+}
+
+int batadv_orig_hash_del_if(struct batadv_hard_iface *hard_iface,
+			    int max_if_num)
+{
+	struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
+	struct batadv_hashtable *hash = bat_priv->orig_hash;
+	struct hlist_head *head;
+	struct batadv_hard_iface *hard_iface_tmp;
+	struct batadv_orig_node *orig_node;
+	uint32_t i;
+	int ret;
+
+	/* resize all orig nodes because orig_node->bcast_own(_sum) depend on
+	 * if_num
+	 */
+	for (i = 0; i < hash->size; i++) {
+		head = &hash->table[i];
+
+		rcu_read_lock();
+		hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
+			spin_lock_bh(&orig_node->ogm_cnt_lock);
+			ret = batadv_orig_node_del_if(orig_node, max_if_num,
+						      hard_iface->if_num);
+			spin_unlock_bh(&orig_node->ogm_cnt_lock);
+
+			if (ret == -ENOMEM)
+				goto err;
+		}
+		rcu_read_unlock();
+	}
+
+	/* renumber remaining batman interfaces _inside_ of orig_hash_lock */
+	rcu_read_lock();
+	list_for_each_entry_rcu(hard_iface_tmp, &batadv_hardif_list, list) {
+		if (hard_iface_tmp->if_status == BATADV_IF_NOT_IN_USE)
+			continue;
+
+		if (hard_iface == hard_iface_tmp)
+			continue;
+
+		if (hard_iface->soft_iface != hard_iface_tmp->soft_iface)
+			continue;
+
+		if (hard_iface_tmp->if_num > hard_iface->if_num)
+			hard_iface_tmp->if_num--;
+	}
+	rcu_read_unlock();
+
+	hard_iface->if_num = -1;
+	return 0;
+
+err:
+	rcu_read_unlock();
+	return -ENOMEM;
+}