The following commit has been merged in the merge/master branch: commit b4dc0270e6c817caf2934f30caaec670715b0d61 Author: Sven Eckelmann sven@narfation.org Date: Sat Jan 16 10:29:53 2016 +0100

batman-adv: Convert batadv_neigh_node to kref

batman-adv uses a self-written reference implementation which is just based on atomic_t. This is less obvious when reading the code than kref and therefore increases the change that the reference counting will be missed.

Signed-off-by: Sven Eckelmann sven@narfation.org Signed-off-by: Marek Lindner mareklindner@neomailbox.ch

diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c index 23ce90e..affcbb5 100644 --- a/net/batman-adv/bat_iv_ogm.c +++ b/net/batman-adv/bat_iv_ogm.c @@ -31,6 +31,7 @@ #include <linux/init.h> #include <linux/jiffies.h> #include <linux/list.h> +#include <linux/kref.h> #include <linux/netdevice.h> #include <linux/pkt_sched.h> #include <linux/printk.h> @@ -1002,7 +1003,7 @@ batadv_iv_ogm_orig_update(struct batadv_priv *bat_priv, neigh_addr = tmp_neigh_node->addr; if (batadv_compare_eth(neigh_addr, ethhdr->h_source) && tmp_neigh_node->if_incoming == if_incoming && - atomic_inc_not_zero(&tmp_neigh_node->refcount)) { + kref_get_unless_zero(&tmp_neigh_node->refcount)) { if (WARN(neigh_node, "too many matching neigh_nodes")) batadv_neigh_node_free_ref(neigh_node); neigh_node = tmp_neigh_node; @@ -1161,7 +1162,7 @@ static int batadv_iv_ogm_calc_tq(struct batadv_orig_node *orig_node, if (tmp_neigh_node->if_incoming != if_incoming) continue;

- if (!atomic_inc_not_zero(&tmp_neigh_node->refcount)) + if (!kref_get_unless_zero(&tmp_neigh_node->refcount)) continue;

neigh_node = tmp_neigh_node; diff --git a/net/batman-adv/originator.c b/net/batman-adv/originator.c index 428983a..9e3dbd8 100644 --- a/net/batman-adv/originator.c +++ b/net/batman-adv/originator.c @@ -229,15 +229,17 @@ void batadv_hardif_neigh_free_ref(struct batadv_hardif_neigh_node *hardif_neigh) /** * batadv_neigh_node_release - release neigh_node from lists and queue for * free after rcu grace period - * @neigh_node: neigh neighbor to free + * @ref: kref pointer of the neigh_node */ -static void batadv_neigh_node_release(struct batadv_neigh_node *neigh_node) +static void batadv_neigh_node_release(struct kref *ref) { 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;

+ neigh_node = container_of(ref, struct batadv_neigh_node, refcount); bao = neigh_node->orig_node->bat_priv->bat_algo_ops;

hlist_for_each_entry_safe(neigh_ifinfo, node_tmp, @@ -262,14 +264,13 @@ static void batadv_neigh_node_release(struct batadv_neigh_node *neigh_node) }

/** - * batadv_neigh_node_free_ref - decrement the neighbors refcounter - * and possibly release it + * batadv_neigh_node_free_ref - decrement the neighbors refcounter and possibly + * release it * @neigh_node: neigh neighbor to free */ void batadv_neigh_node_free_ref(struct batadv_neigh_node *neigh_node) { - if (atomic_dec_and_test(&neigh_node->refcount)) - batadv_neigh_node_release(neigh_node); + kref_put(&neigh_node->refcount, batadv_neigh_node_release); }

/** @@ -298,7 +299,7 @@ batadv_orig_router_get(struct batadv_orig_node *orig_node, break; }

- if (router && !atomic_inc_not_zero(&router->refcount)) + if (router && !kref_get_unless_zero(&router->refcount)) router = NULL;

rcu_read_unlock(); @@ -491,7 +492,7 @@ batadv_neigh_node_get(const struct batadv_orig_node *orig_node, if (tmp_neigh_node->if_incoming != hard_iface) continue;

- if (!atomic_inc_not_zero(&tmp_neigh_node->refcount)) + if (!kref_get_unless_zero(&tmp_neigh_node->refcount)) continue;

res = tmp_neigh_node; @@ -649,7 +650,8 @@ batadv_neigh_node_new(struct batadv_orig_node *orig_node, neigh_node->orig_node = orig_node;

/* extra reference for return */ - atomic_set(&neigh_node->refcount, 2); + kref_init(&neigh_node->refcount); + kref_get(&neigh_node->refcount);

spin_lock_bh(&orig_node->neigh_list_lock); hlist_add_head_rcu(&neigh_node->list, &orig_node->neigh_list); @@ -1084,7 +1086,7 @@ batadv_find_best_neighbor(struct batadv_priv *bat_priv, best, if_outgoing) <= 0)) continue;

- if (!atomic_inc_not_zero(&neigh->refcount)) + if (!kref_get_unless_zero(&neigh->refcount)) continue;

if (best) diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c index 4a5cd8b..205310b 100644 --- a/net/batman-adv/routing.c +++ b/net/batman-adv/routing.c @@ -73,7 +73,7 @@ static void _batadv_update_route(struct batadv_priv *bat_priv,

rcu_read_lock(); curr_router = rcu_dereference(orig_ifinfo->router); - if (curr_router && !atomic_inc_not_zero(&curr_router->refcount)) + if (curr_router && !kref_get_unless_zero(&curr_router->refcount)) curr_router = NULL; rcu_read_unlock();

@@ -101,7 +101,7 @@ static void _batadv_update_route(struct batadv_priv *bat_priv, batadv_neigh_node_free_ref(curr_router);

/* increase refcount of new best neighbor */ - if (neigh_node && !atomic_inc_not_zero(&neigh_node->refcount)) + if (neigh_node && !kref_get_unless_zero(&neigh_node->refcount)) neigh_node = NULL;

spin_lock_bh(&orig_node->neigh_list_lock); @@ -505,7 +505,7 @@ batadv_find_router(struct batadv_priv *bat_priv, if (!cand_router) goto next;

- if (!atomic_inc_not_zero(&cand_router->refcount)) { + if (!kref_get_unless_zero(&cand_router->refcount)) { cand_router = NULL; goto next; } @@ -524,7 +524,7 @@ batadv_find_router(struct batadv_priv *bat_priv,

/* mark the first possible candidate */ if (!first_candidate) { - atomic_inc(&cand_router->refcount); + kref_get(&cand_router->refcount); kref_get(&cand->refcount); first_candidate = cand; first_candidate_router = cand_router; diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h index 6193c01..68ca39e 100644 --- a/net/batman-adv/types.h +++ b/net/batman-adv/types.h @@ -384,7 +384,7 @@ struct batadv_neigh_node { spinlock_t ifinfo_lock; /* protects ifinfo_list and its members */ struct batadv_hard_iface *if_incoming; unsigned long last_seen; - atomic_t refcount; + struct kref refcount; struct rcu_head rcu; };