batman-adv: Convert batadv_orig_ifinfo 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>
Signed-off-by: Antonio Quartulli <a@unstable.cc>

diff --git a/net/batman-adv/originator.c b/net/batman-adv/originator.c
index 1c50abe52c6daeee5f13f33b05c47497b3beee0a..428983a2036f174f5e3fd0fab9425591f78ef0a0 100644 (file)
--- a/net/batman-adv/originator.c
+++ b/net/batman-adv/originator.c
@@ -326,7 +326,7 @@ batadv_orig_ifinfo_get(struct batadv_orig_node *orig_node,
                if (tmp->if_outgoing != if_outgoing)
                        continue;
 
-               if (!atomic_inc_not_zero(&tmp->refcount))
+               if (!kref_get_unless_zero(&tmp->refcount))
                        continue;
 
                orig_ifinfo = tmp;
@@ -377,7 +377,8 @@ batadv_orig_ifinfo_new(struct batadv_orig_node *orig_node,
        orig_ifinfo->batman_seqno_reset = reset_time;
        orig_ifinfo->if_outgoing = if_outgoing;
        INIT_HLIST_NODE(&orig_ifinfo->list);
-       atomic_set(&orig_ifinfo->refcount, 2);
+       kref_init(&orig_ifinfo->refcount);
+       kref_get(&orig_ifinfo->refcount);
        hlist_add_head_rcu(&orig_ifinfo->list,
                           &orig_node->ifinfo_list);
 out:
@@ -704,12 +705,15 @@ int batadv_hardif_neigh_seq_print_text(struct seq_file *seq, void *offset)
 /**
  * batadv_orig_ifinfo_release - release orig_ifinfo from lists and queue for
  *  free after rcu grace period
- * @orig_ifinfo: the orig_ifinfo object to release
+ * @ref: kref pointer of the orig_ifinfo
  */
-static void batadv_orig_ifinfo_release(struct batadv_orig_ifinfo *orig_ifinfo)
+static void batadv_orig_ifinfo_release(struct kref *ref)
 {
+       struct batadv_orig_ifinfo *orig_ifinfo;
        struct batadv_neigh_node *router;
 
+       orig_ifinfo = container_of(ref, struct batadv_orig_ifinfo, refcount);
+
        if (orig_ifinfo->if_outgoing != BATADV_IF_DEFAULT)
                batadv_hardif_free_ref(orig_ifinfo->if_outgoing);
 
@@ -728,8 +732,7 @@ static void batadv_orig_ifinfo_release(struct batadv_orig_ifinfo *orig_ifinfo)
  */
 void batadv_orig_ifinfo_free_ref(struct batadv_orig_ifinfo *orig_ifinfo)
 {
-       if (atomic_dec_and_test(&orig_ifinfo->refcount))
-               batadv_orig_ifinfo_release(orig_ifinfo);
+       kref_put(&orig_ifinfo->refcount, batadv_orig_ifinfo_release);
 }
 
 /**

diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c
index 1c8b35df50cf61448b58bc255618e01b15f1bbb2..4a5cd8bf2661997ae45db39d9f146d6f508d1e3e 100644 (file)
--- a/net/batman-adv/routing.c
+++ b/net/batman-adv/routing.c
@@ -25,6 +25,7 @@
 #include <linux/etherdevice.h>
 #include <linux/if_ether.h>
 #include <linux/jiffies.h>
+#include <linux/kref.h>
 #include <linux/netdevice.h>
 #include <linux/printk.h>
 #include <linux/rculist.h>
@@ -497,7 +498,7 @@ batadv_find_router(struct batadv_priv *bat_priv,
 
        hlist_for_each_entry_rcu(cand, &orig_node->ifinfo_list, list) {
                /* acquire some structures and references ... */
-               if (!atomic_inc_not_zero(&cand->refcount))
+               if (!kref_get_unless_zero(&cand->refcount))
                        continue;
 
                cand_router = rcu_dereference(cand->router);
@@ -524,7 +525,7 @@ batadv_find_router(struct batadv_priv *bat_priv,
                /* mark the first possible candidate */
                if (!first_candidate) {
                        atomic_inc(&cand_router->refcount);
-                       atomic_inc(&cand->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 81d9f8d6c54b36a8a8cd79641ea9852ecea08f02..6193c01b47d24dc1b2115ae3bfae3b137f09041e 100644 (file)
--- a/net/batman-adv/types.h
+++ b/net/batman-adv/types.h
@@ -141,7 +141,7 @@ struct batadv_orig_ifinfo {
        u32 last_real_seqno;
        u8 last_ttl;
        unsigned long batman_seqno_reset;
-       atomic_t refcount;
+       struct kref refcount;
        struct rcu_head rcu;
 };