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 --- v6: - removed patches which are now applied in the branch next - rebased remaining patches on the patch "batman-adv: Avoid recursive call_rcu for batadv_nc_node" which was modified by Marek while he applied the patches (this unfortunately made some of the remaining patches "hard" to apply) v5: - add hack which allows to compile against stable kernel like 3.2.44 which also added the kref_get_unless_zero function v4: - fix function names in commit messages - fix double whitespace in batadv_tt_orig_list_entry_release kerneldoc - add extra patch for batadv_claim_free_ref kerneldoc fix - change the phrase "free it" in all *_free_ref/*_put functions to "release it" v3: - update copyright year v2: - split patchset into fixes and kref migration to make it easier when the decision is made where each patch will be applied
net/batman-adv/distributed-arp-table.c | 2 +- net/batman-adv/gateway_client.c | 4 ++-- net/batman-adv/multicast.c | 7 ++++--- net/batman-adv/network-coding.c | 2 +- net/batman-adv/originator.c | 14 +++++++++----- net/batman-adv/originator.h | 4 ++-- net/batman-adv/translation-table.c | 4 ++-- net/batman-adv/types.h | 2 +- 8 files changed, 22 insertions(+), 17 deletions(-)
diff --git a/net/batman-adv/distributed-arp-table.c b/net/batman-adv/distributed-arp-table.c index 921e252..e326111 100644 --- a/net/batman-adv/distributed-arp-table.c +++ b/net/batman-adv/distributed-arp-table.c @@ -542,7 +542,7 @@ static void batadv_choose_next_candidate(struct batadv_priv *bat_priv, max_orig_node)) continue;
- if (!atomic_inc_not_zero(&orig_node->refcount)) + if (!kref_get_unless_zero(&orig_node->refcount)) continue;
max = tmp_max; diff --git a/net/batman-adv/gateway_client.c b/net/batman-adv/gateway_client.c index 1f3847c..261866e 100644 --- a/net/batman-adv/gateway_client.c +++ b/net/batman-adv/gateway_client.c @@ -118,7 +118,7 @@ batadv_gw_get_selected_orig(struct batadv_priv *bat_priv) if (!orig_node) goto unlock;
- if (!atomic_inc_not_zero(&orig_node->refcount)) + if (!kref_get_unless_zero(&orig_node->refcount)) orig_node = NULL;
unlock: @@ -441,7 +441,7 @@ static void batadv_gw_node_add(struct batadv_priv *bat_priv, if (gateway->bandwidth_down == 0) return;
- if (!atomic_inc_not_zero(&orig_node->refcount)) + if (!kref_get_unless_zero(&orig_node->refcount)) return;
gw_node = kzalloc(sizeof(*gw_node), GFP_ATOMIC); diff --git a/net/batman-adv/multicast.c b/net/batman-adv/multicast.c index 155565e..8caa2c7 100644 --- a/net/batman-adv/multicast.c +++ b/net/batman-adv/multicast.c @@ -30,6 +30,7 @@ #include <linux/in.h> #include <linux/ip.h> #include <linux/ipv6.h> +#include <linux/kref.h> #include <linux/list.h> #include <linux/lockdep.h> #include <linux/netdevice.h> @@ -447,7 +448,7 @@ batadv_mcast_forw_ipv4_node_get(struct batadv_priv *bat_priv) hlist_for_each_entry_rcu(tmp_orig_node, &bat_priv->mcast.want_all_ipv4_list, mcast_want_all_ipv4_node) { - if (!atomic_inc_not_zero(&tmp_orig_node->refcount)) + if (!kref_get_unless_zero(&tmp_orig_node->refcount)) continue;
orig_node = tmp_orig_node; @@ -474,7 +475,7 @@ batadv_mcast_forw_ipv6_node_get(struct batadv_priv *bat_priv) hlist_for_each_entry_rcu(tmp_orig_node, &bat_priv->mcast.want_all_ipv6_list, mcast_want_all_ipv6_node) { - if (!atomic_inc_not_zero(&tmp_orig_node->refcount)) + if (!kref_get_unless_zero(&tmp_orig_node->refcount)) continue;
orig_node = tmp_orig_node; @@ -525,7 +526,7 @@ batadv_mcast_forw_unsnoop_node_get(struct batadv_priv *bat_priv) hlist_for_each_entry_rcu(tmp_orig_node, &bat_priv->mcast.want_all_unsnoopables_list, mcast_want_all_unsnoopables_node) { - if (!atomic_inc_not_zero(&tmp_orig_node->refcount)) + if (!kref_get_unless_zero(&tmp_orig_node->refcount)) continue;
orig_node = tmp_orig_node; diff --git a/net/batman-adv/network-coding.c b/net/batman-adv/network-coding.c index 371fc6b..a4eb8ee 100644 --- a/net/batman-adv/network-coding.c +++ b/net/batman-adv/network-coding.c @@ -858,7 +858,7 @@ static struct batadv_nc_node if (!nc_node) return NULL;
- if (!atomic_inc_not_zero(&orig_neigh_node->refcount)) + if (!kref_get_unless_zero(&orig_neigh_node->refcount)) goto free;
/* Initialize nc_node */ diff --git a/net/batman-adv/originator.c b/net/batman-adv/originator.c index 8b2ef8d..eacd0e5 100644 --- a/net/batman-adv/originator.c +++ b/net/batman-adv/originator.c @@ -18,6 +18,7 @@ #include "originator.h" #include "main.h"
+#include <linux/atomic.h> #include <linux/errno.h> #include <linux/etherdevice.h> #include <linux/fs.h> @@ -775,14 +776,17 @@ static void batadv_orig_node_free_rcu(struct rcu_head *rcu) /** * batadv_orig_node_release - release orig_node from lists and queue for * free after rcu grace period - * @orig_node: the orig node to free + * @ref: kref pointer of the orig_node */ -static void batadv_orig_node_release(struct batadv_orig_node *orig_node) +static void batadv_orig_node_release(struct kref *ref) { struct hlist_node *node_tmp; struct batadv_neigh_node *neigh_node; + struct batadv_orig_node *orig_node; struct batadv_orig_ifinfo *orig_ifinfo;
+ orig_node = container_of(ref, struct batadv_orig_node, refcount); + spin_lock_bh(&orig_node->neigh_list_lock);
/* for all neighbors towards this originator ... */ @@ -812,8 +816,7 @@ static void batadv_orig_node_release(struct batadv_orig_node *orig_node) */ void batadv_orig_node_free_ref(struct batadv_orig_node *orig_node) { - if (atomic_dec_and_test(&orig_node->refcount)) - batadv_orig_node_release(orig_node); + kref_put(&orig_node->refcount, batadv_orig_node_release); }
void batadv_originator_free(struct batadv_priv *bat_priv) @@ -885,7 +888,8 @@ struct batadv_orig_node *batadv_orig_node_new(struct batadv_priv *bat_priv, batadv_nc_init_orig(orig_node);
/* extra reference for return */ - atomic_set(&orig_node->refcount, 2); + kref_init(&orig_node->refcount); + kref_get(&orig_node->refcount);
orig_node->bat_priv = bat_priv; ether_addr_copy(orig_node->orig, addr); diff --git a/net/batman-adv/originator.h b/net/batman-adv/originator.h index 745b4e4..9950740 100644 --- a/net/batman-adv/originator.h +++ b/net/batman-adv/originator.h @@ -20,10 +20,10 @@
#include "main.h"
-#include <linux/atomic.h> #include <linux/compiler.h> #include <linux/if_ether.h> #include <linux/jhash.h> +#include <linux/kref.h> #include <linux/rculist.h> #include <linux/rcupdate.h> #include <linux/stddef.h> @@ -115,7 +115,7 @@ batadv_orig_hash_find(struct batadv_priv *bat_priv, const void *data) if (!batadv_compare_eth(orig_node, data)) continue;
- if (!atomic_inc_not_zero(&orig_node->refcount)) + if (!kref_get_unless_zero(&orig_node->refcount)) continue;
orig_node_tmp = orig_node; diff --git a/net/batman-adv/translation-table.c b/net/batman-adv/translation-table.c index 68494a1..96b1571 100644 --- a/net/batman-adv/translation-table.c +++ b/net/batman-adv/translation-table.c @@ -1334,7 +1334,7 @@ batadv_tt_global_orig_entry_add(struct batadv_tt_global_entry *tt_global, goto out;
INIT_HLIST_NODE(&orig_entry->list); - atomic_inc(&orig_node->refcount); + kref_get(&orig_node->refcount); batadv_tt_global_size_inc(orig_node, tt_global->common.vid); orig_entry->orig_node = orig_node; orig_entry->ttvn = ttvn; @@ -2097,7 +2097,7 @@ struct batadv_orig_node *batadv_transtable_search(struct batadv_priv *bat_priv, /* found anything? */ if (best_entry) orig_node = best_entry->orig_node; - if (orig_node && !atomic_inc_not_zero(&orig_node->refcount)) + if (orig_node && !kref_get_unless_zero(&orig_node->refcount)) orig_node = NULL; rcu_read_unlock();
diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h index 504f3db..aea82a1 100644 --- a/net/batman-adv/types.h +++ b/net/batman-adv/types.h @@ -299,7 +299,7 @@ struct batadv_orig_node { struct batadv_priv *bat_priv; /* bcast_seqno_lock protects: bcast_bits & last_bcast_seqno */ spinlock_t bcast_seqno_lock; - atomic_t refcount; + struct kref refcount; struct rcu_head rcu; #ifdef CONFIG_BATMAN_ADV_NC struct list_head in_coding_list;