The following commit has been merged in the batman-adv/next branch: commit 9c7dafbfab1554705f85523fead578aa1a3d338c Author: Pavel Emelyanov xemul@parallels.com Date: Wed Aug 8 21:52:46 2012 +0000

net: Allow to create links with given ifindex

Currently the RTM_NEWLINK results in -EOPNOTSUPP if the ifinfomsg->ifi_index is not zero. I propose to allow requesting ifindices on link creation. This is required by the checkpoint-restore to correctly restore a net namespace (i.e. -- a container).

Signed-off-by: Pavel Emelyanov xemul@parallels.com Acked-by: Eric Dumazet edumazet@google.com Signed-off-by: David S. Miller davem@davemloft.net

diff --git a/net/core/dev.c b/net/core/dev.c index f91abf8..3ca300d 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -5579,7 +5579,12 @@ int register_netdevice(struct net_device *dev) } }

- dev->ifindex = dev_new_index(net); + ret = -EBUSY; + if (!dev->ifindex) + dev->ifindex = dev_new_index(net); + else if (__dev_get_by_index(net, dev->ifindex)) + goto err_uninit; + if (dev->iflink == -1) dev->iflink = dev->ifindex;

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index db037c9..34d975b 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -1812,8 +1812,6 @@ replay: return -ENODEV; }

- if (ifm->ifi_index) - return -EOPNOTSUPP; if (tb[IFLA_MAP] || tb[IFLA_MASTER] || tb[IFLA_PROTINFO]) return -EOPNOTSUPP;

@@ -1839,10 +1837,14 @@ replay: return PTR_ERR(dest_net);

dev = rtnl_create_link(net, dest_net, ifname, ops, tb); - - if (IS_ERR(dev)) + if (IS_ERR(dev)) { err = PTR_ERR(dev); - else if (ops->newlink) + goto out; + } + + dev->ifindex = ifm->ifi_index; + + if (ops->newlink) err = ops->newlink(net, dev, tb, data); else err = register_netdevice(dev);