net_sched: fix regression in tc_action_ops

[~andy/linux] / net / sched / act_api.c

diff --git a/net/sched/act_api.c b/net/sched/act_api.c
index dc457c9576568ebab3ed62ed8ead66241328dfea..dce2b6ecdbd897371dbe93decefc58aa2deca223 100644 (file)
--- a/net/sched/act_api.c
+++ b/net/sched/act_api.c
@@ -255,12 +255,12 @@ void tcf_hash_insert(struct tcf_common *p, struct tcf_hashinfo *hinfo)
 }
 EXPORT_SYMBOL(tcf_hash_insert);
 
-static struct tc_action_ops *act_base = NULL;
+static LIST_HEAD(act_base);
 static DEFINE_RWLOCK(act_mod_lock);
 
 int tcf_register_action(struct tc_action_ops *act)
 {
-       struct tc_action_ops *a, **ap;
+       struct tc_action_ops *a;
 
        /* Must supply act, dump, cleanup and init */
        if (!act->act || !act->dump || !act->cleanup || !act->init)
@@ -273,14 +273,13 @@ int tcf_register_action(struct tc_action_ops *act)
                act->walk = tcf_generic_walker;
 
        write_lock(&act_mod_lock);
-       for (ap = &act_base; (a = *ap) != NULL; ap = &a->next) {
+       list_for_each_entry(a, &act_base, head) {
                if (act->type == a->type || (strcmp(act->kind, a->kind) == 0)) {
                        write_unlock(&act_mod_lock);
                        return -EEXIST;
                }
        }
-       act->next = NULL;
-       *ap = act;
+       list_add_tail(&act->head, &act_base);
        write_unlock(&act_mod_lock);
        return 0;
 }
@@ -288,17 +287,16 @@ EXPORT_SYMBOL(tcf_register_action);
 
 int tcf_unregister_action(struct tc_action_ops *act)
 {
-       struct tc_action_ops *a, **ap;
+       struct tc_action_ops *a;
        int err = -ENOENT;
 
        write_lock(&act_mod_lock);
-       for (ap = &act_base; (a = *ap) != NULL; ap = &a->next)
-               if (a == act)
+       list_for_each_entry(a, &act_base, head) {
+               if (a == act) {
+                       list_del(&act->head);
+                       err = 0;
                        break;
-       if (a) {
-               *ap = a->next;
-               a->next = NULL;
-               err = 0;
+               }
        }
        write_unlock(&act_mod_lock);
        return err;
@@ -308,67 +306,40 @@ EXPORT_SYMBOL(tcf_unregister_action);
 /* lookup by name */
 static struct tc_action_ops *tc_lookup_action_n(char *kind)
 {
-       struct tc_action_ops *a = NULL;
+       struct tc_action_ops *a, *res = NULL;
 
        if (kind) {
                read_lock(&act_mod_lock);
-               for (a = act_base; a; a = a->next) {
+               list_for_each_entry(a, &act_base, head) {
                        if (strcmp(kind, a->kind) == 0) {
-                               if (!try_module_get(a->owner)) {
-                                       read_unlock(&act_mod_lock);
-                                       return NULL;
-                               }
+                               if (try_module_get(a->owner))
+                                       res = a;
                                break;
                        }
                }
                read_unlock(&act_mod_lock);
        }
-       return a;
+       return res;
 }
 
 /* lookup by nlattr */
 static struct tc_action_ops *tc_lookup_action(struct nlattr *kind)
 {
-       struct tc_action_ops *a = NULL;
+       struct tc_action_ops *a, *res = NULL;
 
        if (kind) {
                read_lock(&act_mod_lock);
-               for (a = act_base; a; a = a->next) {
+               list_for_each_entry(a, &act_base, head) {
                        if (nla_strcmp(kind, a->kind) == 0) {
-                               if (!try_module_get(a->owner)) {
-                                       read_unlock(&act_mod_lock);
-                                       return NULL;
-                               }
-                               break;
-                       }
-               }
-               read_unlock(&act_mod_lock);
-       }
-       return a;
-}
-
-#if 0
-/* lookup by id */
-static struct tc_action_ops *tc_lookup_action_id(u32 type)
-{
-       struct tc_action_ops *a = NULL;
-
-       if (type) {
-               read_lock(&act_mod_lock);
-               for (a = act_base; a; a = a->next) {
-                       if (a->type == type) {
-                               if (!try_module_get(a->owner)) {
-                                       read_unlock(&act_mod_lock);
-                                       return NULL;
-                               }
+                               if (try_module_get(a->owner))
+                                       res = a;
                                break;
                        }
                }
                read_unlock(&act_mod_lock);
        }
-       return a;
+       return res;
 }
-#endif
 
 int tcf_action_exec(struct sk_buff *skb, const struct list_head *actions,
                    struct tcf_result *res)