batman-adv: Convert batadv_hard_iface 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>

net/batman-adv/originator.c

@@ -367,7 +367,7 @@ batadv_orig_ifinfo_new(struct batadv_orig_node *orig_node,
 		goto out;
 
 	if (if_outgoing != BATADV_IF_DEFAULT &&
-	    !atomic_inc_not_zero(&if_outgoing->refcount)) {
+	    !kref_get_unless_zero(&if_outgoing->refcount)) {
 		kfree(orig_ifinfo);
 		orig_ifinfo = NULL;
 		goto out;
@@ -447,7 +447,7 @@ batadv_neigh_ifinfo_new(struct batadv_neigh_node *neigh,
 	if (!neigh_ifinfo)
 		goto out;
 
-	if (if_outgoing && !atomic_inc_not_zero(&if_outgoing->refcount)) {
+	if (if_outgoing && !kref_get_unless_zero(&if_outgoing->refcount)) {
 		kfree(neigh_ifinfo);
 		neigh_ifinfo = NULL;
 		goto out;
@@ -524,7 +524,7 @@ batadv_hardif_neigh_create(struct batadv_hard_iface *hard_iface,
 	if (hardif_neigh)
 		goto out;
 
-	if (!atomic_inc_not_zero(&hard_iface->refcount))
+	if (!kref_get_unless_zero(&hard_iface->refcount))
 		goto out;
 
 	hardif_neigh = kzalloc(sizeof(*hardif_neigh), GFP_ATOMIC);
@@ -635,7 +635,7 @@ batadv_neigh_node_new(struct batadv_orig_node *orig_node,
 	if (!neigh_node)
 		goto out;
 
-	if (!atomic_inc_not_zero(&hard_iface->refcount)) {
+	if (!kref_get_unless_zero(&hard_iface->refcount)) {
 		kfree(neigh_node);
 		neigh_node = NULL;
 		goto out;