netns: notify new nsid outside __peernet2id()

There is no functional change with this patch. It will ease the refactoring
of the locking system that protects nsids and the support of the netlink
socket option NETLINK_LISTEN_ALL_NSID.

Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c
index 9c806ac..ee86424 100644 (file)
--- a/net/core/net_namespace.c
+++ b/net/core/net_namespace.c
@@ -147,10 +147,9 @@ static void ops_free_list(const struct pernet_operations *ops,
        }
 }
 
-static void rtnl_net_notifyid(struct net *net, int cmd, int id);
 static int alloc_netid(struct net *net, struct net *peer, int reqid)
 {
-       int min = 0, max = 0, id;
+       int min = 0, max = 0;
 
        ASSERT_RTNL();
 
@@ -159,11 +158,7 @@ static int alloc_netid(struct net *net, struct net *peer, int reqid)
                max = reqid + 1;
        }
 
-       id = idr_alloc(&net->netns_ids, peer, min, max, GFP_KERNEL);
-       if (id >= 0)
-               rtnl_net_notifyid(net, RTM_NEWNSID, id);
-
-       return id;
+       return idr_alloc(&net->netns_ids, peer, min, max, GFP_KERNEL);
 }
 
 /* This function is used by idr_for_each(). If net is equal to peer, the
@@ -179,34 +174,50 @@ static int net_eq_idr(int id, void *net, void *peer)
        return 0;
 }
 
-static int __peernet2id(struct net *net, struct net *peer, bool alloc)
+static int __peernet2id_alloc(struct net *net, struct net *peer, bool *alloc)
 {
        int id = idr_for_each(&net->netns_ids, net_eq_idr, peer);
+       bool alloc_it = *alloc;
 
        ASSERT_RTNL();
 
+       *alloc = false;
+
        /* Magic value for id 0. */
        if (id == NET_ID_ZERO)
                return 0;
        if (id > 0)
                return id;
 
-       if (alloc) {
+       if (alloc_it) {
                id = alloc_netid(net, peer, -1);
+               *alloc = true;
                return id >= 0 ? id : NETNSA_NSID_NOT_ASSIGNED;
        }
 
        return NETNSA_NSID_NOT_ASSIGNED;
 }
 
+static int __peernet2id(struct net *net, struct net *peer)
+{
+       bool no = false;
+
+       return __peernet2id_alloc(net, peer, &no);
+}
+
+static void rtnl_net_notifyid(struct net *net, int cmd, int id);
 /* This function returns the id of a peer netns. If no id is assigned, one will
  * be allocated and returned.
  */
 int peernet2id_alloc(struct net *net, struct net *peer)
 {
        bool alloc = atomic_read(&peer->count) == 0 ? false : true;
+       int id;
 
-       return __peernet2id(net, peer, alloc);
+       id = __peernet2id_alloc(net, peer, &alloc);
+       if (alloc && id >= 0)
+               rtnl_net_notifyid(net, RTM_NEWNSID, id);
+       return id;
 }
 EXPORT_SYMBOL(peernet2id_alloc);
 
@@ -361,7 +372,7 @@ static void cleanup_net(struct work_struct *work)
                list_del_rcu(&net->list);
                list_add_tail(&net->exit_list, &net_exit_list);
                for_each_net(tmp) {
-                       int id = __peernet2id(tmp, net, false);
+                       int id = __peernet2id(tmp, net);
 
                        if (id >= 0) {
                                rtnl_net_notifyid(tmp, RTM_DELNSID, id);
@@ -516,14 +527,16 @@ static int rtnl_net_newid(struct sk_buff *skb, struct nlmsghdr *nlh)
        if (IS_ERR(peer))
                return PTR_ERR(peer);
 
-       if (__peernet2id(net, peer, false) >= 0) {
+       if (__peernet2id(net, peer) >= 0) {
                err = -EEXIST;
                goto out;
        }
 
        err = alloc_netid(net, peer, nsid);
-       if (err > 0)
+       if (err >= 0) {
+               rtnl_net_notifyid(net, RTM_NEWNSID, err);
                err = 0;
+       }
 out:
        put_net(peer);
        return err;
@@ -588,7 +601,7 @@ static int rtnl_net_getid(struct sk_buff *skb, struct nlmsghdr *nlh)
                goto out;
        }
 
-       id = __peernet2id(net, peer, false);
+       id = __peernet2id(net, peer);
        err = rtnl_net_fill(msg, NETLINK_CB(skb).portid, nlh->nlmsg_seq, 0,
                            RTM_GETNSID, net, id);
        if (err < 0)