From cef63419f7dbd52e535d1932a88904b3facb1546 Mon Sep 17 00:00:00 2001 From: Marek Lindner Date: Tue, 4 Aug 2015 21:09:55 +0800 Subject: batman-adv: add list of unique single hop neighbors per hard-interface Signed-off-by: Marek Lindner Signed-off-by: Antonio Quartulli --- net/batman-adv/originator.c | 157 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 157 insertions(+) (limited to 'net/batman-adv/originator.c') diff --git a/net/batman-adv/originator.c b/net/batman-adv/originator.c index 7486df9ed48d..a8671c656742 100644 --- a/net/batman-adv/originator.c +++ b/net/batman-adv/originator.c @@ -201,6 +201,47 @@ void batadv_neigh_ifinfo_free_ref(struct batadv_neigh_ifinfo *neigh_ifinfo) call_rcu(&neigh_ifinfo->rcu, batadv_neigh_ifinfo_free_rcu); } +/** + * batadv_hardif_neigh_free_rcu - free the hardif neigh_node + * @rcu: rcu pointer of the neigh_node + */ +static void batadv_hardif_neigh_free_rcu(struct rcu_head *rcu) +{ + struct batadv_hardif_neigh_node *hardif_neigh; + + hardif_neigh = container_of(rcu, struct batadv_hardif_neigh_node, rcu); + + spin_lock_bh(&hardif_neigh->if_incoming->neigh_list_lock); + hlist_del_init_rcu(&hardif_neigh->list); + spin_unlock_bh(&hardif_neigh->if_incoming->neigh_list_lock); + + batadv_hardif_free_ref_now(hardif_neigh->if_incoming); + kfree(hardif_neigh); +} + +/** + * batadv_hardif_neigh_free_now - decrement the hardif neighbors refcounter + * and possibly free it (without rcu callback) + * @hardif_neigh: hardif neigh neighbor to free + */ +static void +batadv_hardif_neigh_free_now(struct batadv_hardif_neigh_node *hardif_neigh) +{ + if (atomic_dec_and_test(&hardif_neigh->refcount)) + batadv_hardif_neigh_free_rcu(&hardif_neigh->rcu); +} + +/** + * batadv_hardif_neigh_free_ref - decrement the hardif neighbors refcounter + * and possibly free it + * @hardif_neigh: hardif neigh neighbor to free + */ +void batadv_hardif_neigh_free_ref(struct batadv_hardif_neigh_node *hardif_neigh) +{ + if (atomic_dec_and_test(&hardif_neigh->refcount)) + call_rcu(&hardif_neigh->rcu, batadv_hardif_neigh_free_rcu); +} + /** * batadv_neigh_node_free_rcu - free the neigh_node * @rcu: rcu pointer of the neigh_node @@ -209,6 +250,7 @@ static void batadv_neigh_node_free_rcu(struct rcu_head *rcu) { struct hlist_node *node_tmp; struct batadv_neigh_node *neigh_node; + struct batadv_hardif_neigh_node *hardif_neigh; struct batadv_neigh_ifinfo *neigh_ifinfo; struct batadv_algo_ops *bao; @@ -220,6 +262,14 @@ static void batadv_neigh_node_free_rcu(struct rcu_head *rcu) batadv_neigh_ifinfo_free_ref_now(neigh_ifinfo); } + hardif_neigh = batadv_hardif_neigh_get(neigh_node->if_incoming, + neigh_node->addr); + if (hardif_neigh) { + /* batadv_hardif_neigh_get() increases refcount too */ + batadv_hardif_neigh_free_now(hardif_neigh); + batadv_hardif_neigh_free_now(hardif_neigh); + } + if (bao->bat_neigh_free) bao->bat_neigh_free(neigh_node); @@ -478,6 +528,102 @@ batadv_neigh_node_get(const struct batadv_orig_node *orig_node, return res; } +/** + * batadv_hardif_neigh_create - create a hardif neighbour node + * @hard_iface: the interface this neighbour is connected to + * @neigh_addr: the interface address of the neighbour to retrieve + * + * Returns the hardif neighbour node if found or created or NULL otherwise. + */ +static struct batadv_hardif_neigh_node * +batadv_hardif_neigh_create(struct batadv_hard_iface *hard_iface, + const u8 *neigh_addr) +{ + struct batadv_hardif_neigh_node *hardif_neigh = NULL; + + spin_lock_bh(&hard_iface->neigh_list_lock); + + /* check if neighbor hasn't been added in the meantime */ + hardif_neigh = batadv_hardif_neigh_get(hard_iface, neigh_addr); + if (hardif_neigh) + goto out; + + if (!atomic_inc_not_zero(&hard_iface->refcount)) + goto out; + + hardif_neigh = kzalloc(sizeof(*hardif_neigh), GFP_ATOMIC); + if (!hardif_neigh) { + batadv_hardif_free_ref(hard_iface); + goto out; + } + + INIT_HLIST_NODE(&hardif_neigh->list); + ether_addr_copy(hardif_neigh->addr, neigh_addr); + hardif_neigh->if_incoming = hard_iface; + hardif_neigh->last_seen = jiffies; + + atomic_set(&hardif_neigh->refcount, 1); + + hlist_add_head(&hardif_neigh->list, &hard_iface->neigh_list); + +out: + spin_unlock_bh(&hard_iface->neigh_list_lock); + return hardif_neigh; +} + +/** + * batadv_hardif_neigh_get_or_create - retrieve or create a hardif neighbour + * node + * @hard_iface: the interface this neighbour is connected to + * @neigh_addr: the interface address of the neighbour to retrieve + * + * Returns the hardif neighbour node if found or created or NULL otherwise. + */ +static struct batadv_hardif_neigh_node * +batadv_hardif_neigh_get_or_create(struct batadv_hard_iface *hard_iface, + const u8 *neigh_addr) +{ + struct batadv_hardif_neigh_node *hardif_neigh = NULL; + + /* first check without locking to avoid the overhead */ + hardif_neigh = batadv_hardif_neigh_get(hard_iface, neigh_addr); + if (hardif_neigh) + return hardif_neigh; + + return batadv_hardif_neigh_create(hard_iface, neigh_addr); +} + +/** + * batadv_hardif_neigh_get - retrieve a hardif neighbour from the list + * @hard_iface: the interface where this neighbour is connected to + * @neigh_addr: the address of the neighbour + * + * Looks for and possibly returns a neighbour belonging to this hard interface. + * Returns NULL if the neighbour is not found. + */ +struct batadv_hardif_neigh_node * +batadv_hardif_neigh_get(const struct batadv_hard_iface *hard_iface, + const u8 *neigh_addr) +{ + struct batadv_hardif_neigh_node *tmp_hardif_neigh, *hardif_neigh = NULL; + + rcu_read_lock(); + hlist_for_each_entry_rcu(tmp_hardif_neigh, + &hard_iface->neigh_list, list) { + if (!batadv_compare_eth(tmp_hardif_neigh->addr, neigh_addr)) + continue; + + if (!atomic_inc_not_zero(&tmp_hardif_neigh->refcount)) + continue; + + hardif_neigh = tmp_hardif_neigh; + break; + } + rcu_read_unlock(); + + return hardif_neigh; +} + /** * batadv_neigh_node_new - create and init a new neigh_node object * @orig_node: originator object representing the neighbour @@ -493,11 +639,17 @@ batadv_neigh_node_new(struct batadv_orig_node *orig_node, const u8 *neigh_addr) { struct batadv_neigh_node *neigh_node; + struct batadv_hardif_neigh_node *hardif_neigh = NULL; neigh_node = batadv_neigh_node_get(orig_node, hard_iface, neigh_addr); if (neigh_node) goto out; + hardif_neigh = batadv_hardif_neigh_get_or_create(hard_iface, + neigh_addr); + if (!hardif_neigh) + goto out; + neigh_node = kzalloc(sizeof(*neigh_node), GFP_ATOMIC); if (!neigh_node) goto out; @@ -523,11 +675,16 @@ batadv_neigh_node_new(struct batadv_orig_node *orig_node, hlist_add_head_rcu(&neigh_node->list, &orig_node->neigh_list); spin_unlock_bh(&orig_node->neigh_list_lock); + /* increment unique neighbor refcount */ + atomic_inc(&hardif_neigh->refcount); + batadv_dbg(BATADV_DBG_BATMAN, orig_node->bat_priv, "Creating new neighbor %pM for orig_node %pM on interface %s\n", neigh_addr, orig_node->orig, hard_iface->net_dev->name); out: + if (hardif_neigh) + batadv_hardif_neigh_free_ref(hardif_neigh); return neigh_node; } -- cgit v1.2.3