[PATCH 08/21] batman-adv: Convert batadv_bla_claim to kref

[Antonio Quartulli]

From: Sven Eckelmann <s...@narfation.org>

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 <s...@narfation.org>
Signed-off-by: Marek Lindner <mareklind...@neomailbox.ch>
Signed-off-by: Antonio Quartulli <a...@unstable.cc>
---
 net/batman-adv/bridge_loop_avoidance.c | 14 +++++++++-----
 net/batman-adv/types.h                 |  2 +-
 2 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/net/batman-adv/bridge_loop_avoidance.c 
b/net/batman-adv/bridge_loop_avoidance.c
index 41116e4c2e34..7781f39c174d 100644
--- a/net/batman-adv/bridge_loop_avoidance.c
+++ b/net/batman-adv/bridge_loop_avoidance.c
@@ -174,8 +174,12 @@ batadv_backbone_gw_free_ref(struct batadv_bla_backbone_gw 
*backbone_gw)
  *  grace period
  * @ref: kref pointer of the claim
  */
-static void batadv_claim_release(struct batadv_bla_claim *claim)
+static void batadv_claim_release(struct kref *ref)
 {
+       struct batadv_bla_claim *claim;
+
+       claim = container_of(ref, struct batadv_bla_claim, refcount);
+
        batadv_backbone_gw_free_ref(claim->backbone_gw);
        kfree_rcu(claim, rcu);
 }
@@ -187,8 +191,7 @@ static void batadv_claim_release(struct batadv_bla_claim 
*claim)
  */
 static void batadv_claim_free_ref(struct batadv_bla_claim *claim)
 {
-       if (atomic_dec_and_test(&claim->refcount))
-               batadv_claim_release(claim);
+       kref_put(&claim->refcount, batadv_claim_release);
 }
 
 /**
@@ -219,7 +222,7 @@ static struct batadv_bla_claim
                if (!batadv_compare_claim(&claim->hash_entry, data))
                        continue;
 
-               if (!atomic_inc_not_zero(&claim->refcount))
+               if (!kref_get_unless_zero(&claim->refcount))
                        continue;
 
                claim_tmp = claim;
@@ -651,7 +654,8 @@ static void batadv_bla_add_claim(struct batadv_priv 
*bat_priv,
                claim->lasttime = jiffies;
                claim->backbone_gw = backbone_gw;
 
-               atomic_set(&claim->refcount, 2);
+               kref_init(&claim->refcount);
+               kref_get(&claim->refcount);
                batadv_dbg(BATADV_DBG_BLA, bat_priv,
                           "bla_add_claim(): adding new entry %pM, vid %d to 
hash ...\n",
                           mac, BATADV_PRINT_VID(vid));
diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h
index 595f52400b1f..34c13b65bec2 100644
--- a/net/batman-adv/types.h
+++ b/net/batman-adv/types.h
@@ -951,7 +951,7 @@ struct batadv_bla_claim {
        unsigned long lasttime;
        struct hlist_node hash_entry;
        struct rcu_head rcu;
-       atomic_t refcount;
+       struct kref refcount;
 };
 #endif
 
-- 
2.7.1