From: Pavel Emelyanov <xemul@parallels•com>
To: Linux Netdev List <netdev@vger•kernel.org>,
David Miller <davem@davemloft•net>
Subject: [PATCH 1/2] net: Allow to create links with given ifindex
Date: Mon, 30 Jul 2012 08:34:55 +0400 [thread overview]
Message-ID: <50160EEF.6050406@parallels.com> (raw)
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). The question what to do with pre-created devices such
as lo or sit fbdev is open, but for manually created devices this can be
solved by this patch.
Signed-off-by: Pavel Emelyanov <xemul@parallels•com>
---
diff --git a/net/core/dev.c b/net/core/dev.c
index 0ebaea1..5966e2f 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -5533,7 +5533,12 @@ 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 334b930..76e19aa 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -1801,8 +1801,6 @@ replay:
return -ENODEV;
}
- if (ifm->ifi_index)
- return -EOPNOTSUPP;
if (tb[IFLA_MAP] || tb[IFLA_MASTER] || tb[IFLA_PROTINFO])
return -EOPNOTSUPP;
@@ -1828,10 +1826,14 @@ 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);
next reply other threads:[~2012-07-30 4:35 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-07-30 4:34 Pavel Emelyanov [this message]
2012-07-30 4:36 ` [PATCH 2/2] veth: Allow to create peer link with given ifindex Pavel Emelyanov
2012-07-30 10:49 ` [PATCH 1/2] net: Allow to create links " Eric W. Biederman
2012-07-30 10:56 ` Eric W. Biederman
2012-07-31 9:03 ` Pavel Emelyanov
2012-07-31 11:58 ` Eric W. Biederman
2012-07-31 13:30 ` Pavel Emelyanov
2012-08-02 10:28 ` Eric Dumazet
2012-08-02 11:09 ` Eric W. Biederman
2012-08-02 23:37 ` David Miller
2012-08-02 23:26 ` David Miller
2012-08-03 5:45 ` Eric Dumazet
2012-08-03 5:51 ` Eric Dumazet
2012-08-03 23:56 ` David Miller
2012-08-04 7:10 ` Eric Dumazet
2012-08-04 8:25 ` David Miller
2012-07-30 11:51 ` Eric Dumazet
2012-07-30 12:33 ` Eric W. Biederman
2012-07-31 9:06 ` Pavel Emelyanov
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