Techwizz/kernel-fxtec-pro1x
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity

net: disallow to use net_assign_generic externally

Browse source 
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>
This commit is contained in:
Jiri Pirko 2010-04-23 01:40:47 +00:00 committed by David S. Miller
parent 47d54d6582
commit 05fceb4ad7
2 changed files with 47 additions and 53 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

9
include/net/netns/generic.h
View file

@ -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.
*
@ -46,6 +43,4 @@ static inline void *net_generic(struct net *net, int id)
return ptr;
}
extern int net_assign_generic(struct net *net, int id, void *data);
#endif

91
net/core/net_namespace.c
View file

@ -27,6 +27,51 @@ EXPORT_SYMBOL(init_net);
#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;
@ -526,49 +571,3 @@ void unregister_pernet_device(struct pernet_operations *ops)
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);