net: disallow to use net_assign_generic externally

Now there's no need to use this fuction directly because it's handled by register_pernet_device. So to make this simple and easy to understand, make this static to do not tempt potentional users. Signed-off-by: Jiri Pirko <jpirko@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>

net: disallow to use net_assign_generic externally
Now there's no need to use this fuction directly because it's handled by register_pernet_device. So to make this simple and easy to understand, make this static to do not tempt potentional users. Signed-off-by: Jiri Pirko <jpirko@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Jiri Pirko · David S. Miller
1 parent 47d54d6582
Showing 2 changed files with 47 additions and 53 deletions Side-by-side Diff
include/net/netns/generic.h
net/core/net_namespace.c
@@ -14,11 +14,8 @@
  * The rules are simple:
  * 1. set pernet_operations->id.  After register_pernet_device you
  *    will have the id of your private pointer.
- * 2. Either set pernet_operations->size (to have the code allocate and
- *    free a private structure pointed to from struct net ) or 
- *    call net_assign_generic() to put the private data on the struct
- *    net (most preferably this should be done in the ->init callback
- *    of the ops registered);
+ * 2. set pernet_operations->size to have the code allocate and free
+ *    a private structure pointed to from struct net.
  * 3. do not change this pointer while the net is alive;
  * 4. do not try to have any private reference on the net_generic object.
  *
@@ -46,7 +43,5 @@
  
 	return ptr;
 }
-
-extern int net_assign_generic(struct net *net, int id, void *data);
 #endif
@@ -27,6 +27,51 @@
  
 #define INITIAL_NET_GEN_PTRS	13 /* +1 for len +2 for rcu_head */
  
+static void net_generic_release(struct rcu_head *rcu)
+{
+	struct net_generic *ng;
+
+	ng = container_of(rcu, struct net_generic, rcu);
+	kfree(ng);
+}
+
+static int net_assign_generic(struct net *net, int id, void *data)
+{
+	struct net_generic *ng, *old_ng;
+
+	BUG_ON(!mutex_is_locked(&net_mutex));
+	BUG_ON(id == 0);
+
+	ng = old_ng = net->gen;
+	if (old_ng->len >= id)
+		goto assign;
+
+	ng = kzalloc(sizeof(struct net_generic) +
+			id * sizeof(void *), GFP_KERNEL);
+	if (ng == NULL)
+		return -ENOMEM;
+
+	/*
+	 * Some synchronisation notes:
+	 *
+	 * The net_generic explores the net->gen array inside rcu
+	 * read section. Besides once set the net->gen->ptr[x]
+	 * pointer never changes (see rules in netns/generic.h).
+	 *
+	 * That said, we simply duplicate this array and schedule
+	 * the old copy for kfree after a grace period.
+	 */
+
+	ng->len = id;
+	memcpy(&ng->ptr, &old_ng->ptr, old_ng->len * sizeof(void*));
+
+	rcu_assign_pointer(net->gen, ng);
+	call_rcu(&old_ng->rcu, net_generic_release);
+assign:
+	ng->ptr[id - 1] = data;
+	return 0;
+}
+
 static int ops_init(const struct pernet_operations *ops, struct net *net)
 {
 	int err;
@@ -526,50 +571,4 @@
 	mutex_unlock(&net_mutex);
 }
 EXPORT_SYMBOL_GPL(unregister_pernet_device);
-
-static void net_generic_release(struct rcu_head *rcu)
-{
-	struct net_generic *ng;
-
-	ng = container_of(rcu, struct net_generic, rcu);
-	kfree(ng);
-}
-
-int net_assign_generic(struct net *net, int id, void *data)
-{
-	struct net_generic *ng, *old_ng;
-
-	BUG_ON(!mutex_is_locked(&net_mutex));
-	BUG_ON(id == 0);
-
-	ng = old_ng = net->gen;
-	if (old_ng->len >= id)
-		goto assign;
-
-	ng = kzalloc(sizeof(struct net_generic) +
-			id * sizeof(void *), GFP_KERNEL);
-	if (ng == NULL)
-		return -ENOMEM;
-
-	/*
-	 * Some synchronisation notes:
-	 *
-	 * The net_generic explores the net->gen array inside rcu
-	 * read section. Besides once set the net->gen->ptr[x]
-	 * pointer never changes (see rules in netns/generic.h).
-	 *
-	 * That said, we simply duplicate this array and schedule
-	 * the old copy for kfree after a grace period.
-	 */
-
-	ng->len = id;
-	memcpy(&ng->ptr, &old_ng->ptr, old_ng->len * sizeof(void*));
-
-	rcu_assign_pointer(net->gen, ng);
-	call_rcu(&old_ng->rcu, net_generic_release);
-assign:
-	ng->ptr[id - 1] = data;
-	return 0;
-}
-EXPORT_SYMBOL_GPL(net_assign_generic);
...	...	@@ -14,11 +14,8 @@
14	14	* The rules are simple:
15	15	* 1. set pernet_operations->id. After register_pernet_device you
16	16	* will have the id of your private pointer.
17		- * 2. Either set pernet_operations->size (to have the code allocate and
18		- * free a private structure pointed to from struct net ) or
19		- * call net_assign_generic() to put the private data on the struct
20		- * net (most preferably this should be done in the ->init callback
21		- * of the ops registered);
	17	+ * 2. set pernet_operations->size to have the code allocate and free
	18	+ * a private structure pointed to from struct net.
22	19	* 3. do not change this pointer while the net is alive;
23	20	* 4. do not try to have any private reference on the net_generic object.
24	21	*
...	...	@@ -46,7 +43,5 @@
46	43
47	44	return ptr;
48	45	}
49		-
50		-extern int net_assign_generic(struct net net, int id, void data);
51	46	#endif
...	...	@@ -27,6 +27,51 @@
27	27
28	28	#define INITIAL_NET_GEN_PTRS 13 /* +1 for len +2 for rcu_head */
29	29
	30	+static void net_generic_release(struct rcu_head *rcu)
	31	+{
	32	+ struct net_generic *ng;
	33	+
	34	+ ng = container_of(rcu, struct net_generic, rcu);
	35	+ kfree(ng);
	36	+}
	37	+
	38	+static int net_assign_generic(struct net net, int id, void data)
	39	+{
	40	+ struct net_generic ng, old_ng;
	41	+
	42	+ BUG_ON(!mutex_is_locked(&net_mutex));
	43	+ BUG_ON(id == 0);
	44	+
	45	+ ng = old_ng = net->gen;
	46	+ if (old_ng->len >= id)
	47	+ goto assign;
	48	+
	49	+ ng = kzalloc(sizeof(struct net_generic) +
	50	+ id * sizeof(void *), GFP_KERNEL);
	51	+ if (ng == NULL)
	52	+ return -ENOMEM;
	53	+
	54	+ /*
	55	+ * Some synchronisation notes:
	56	+ *
	57	+ * The net_generic explores the net->gen array inside rcu
	58	+ * read section. Besides once set the net->gen->ptr[x]
	59	+ * pointer never changes (see rules in netns/generic.h).
	60	+ *
	61	+ * That said, we simply duplicate this array and schedule
	62	+ * the old copy for kfree after a grace period.
	63	+ */
	64	+
	65	+ ng->len = id;
	66	+ memcpy(&ng->ptr, &old_ng->ptr, old_ng->len * sizeof(void*));
	67	+
	68	+ rcu_assign_pointer(net->gen, ng);
	69	+ call_rcu(&old_ng->rcu, net_generic_release);
	70	+assign:
	71	+ ng->ptr[id - 1] = data;
	72	+ return 0;
	73	+}
	74	+
30	75	static int ops_init(const struct pernet_operations ops, struct net net)
31	76	{
32	77	int err;
...	...	@@ -526,50 +571,4 @@
526	571	mutex_unlock(&net_mutex);
527	572	}
528	573	EXPORT_SYMBOL_GPL(unregister_pernet_device);
529		-
530		-static void net_generic_release(struct rcu_head *rcu)
531		-{
532		- struct net_generic *ng;
533		-
534		- ng = container_of(rcu, struct net_generic, rcu);
535		- kfree(ng);
536		-}
537		-
538		-int net_assign_generic(struct net net, int id, void data)
539		-{
540		- struct net_generic ng, old_ng;
541		-
542		- BUG_ON(!mutex_is_locked(&net_mutex));
543		- BUG_ON(id == 0);
544		-
545		- ng = old_ng = net->gen;
546		- if (old_ng->len >= id)
547		- goto assign;
548		-
549		- ng = kzalloc(sizeof(struct net_generic) +
550		- id * sizeof(void *), GFP_KERNEL);
551		- if (ng == NULL)
552		- return -ENOMEM;
553		-
554		- /*
555		- * Some synchronisation notes:
556		- *
557		- * The net_generic explores the net->gen array inside rcu
558		- * read section. Besides once set the net->gen->ptr[x]
559		- * pointer never changes (see rules in netns/generic.h).
560		- *
561		- * That said, we simply duplicate this array and schedule
562		- * the old copy for kfree after a grace period.
563		- */
564		-
565		- ng->len = id;
566		- memcpy(&ng->ptr, &old_ng->ptr, old_ng->len * sizeof(void*));
567		-
568		- rcu_assign_pointer(net->gen, ng);
569		- call_rcu(&old_ng->rcu, net_generic_release);
570		-assign:
571		- ng->ptr[id - 1] = data;
572		- return 0;
573		-}
574		-EXPORT_SYMBOL_GPL(net_assign_generic);