[PATCH net-next v4 0/4] netns: allow to identify peer netns

[David Miller]

From: ebiederm at xmission.com (Eric W. Biederman)
Date: Thu, 30 Oct 2014 11:41:03 -0700

> Nicolas Dichtel <nicolas.dichtel at 6wind.com> writes:
> 
>> The goal of this serie is to be able to multicast netlink messages with an
>> attribute that identify a peer netns.
>> This is needed by the userland to interpret some informations contained in
>> netlink messages (like IFLA_LINK value, but also some other attributes in case
>> of x-netns netdevice (see also
>> http://thread.gmane.org/gmane.linux.network/315933/focus=316064 and
>> http://thread.gmane.org/gmane.linux.kernel.containers/28301/focus=4239)).
>>
>> Ids of peer netns are set by userland via a new genl messages. These ids are
>> stored per netns and are local (ie only valid in the netns where they are set).
>> To avoid allocating an int for each peer netns, I use idr_for_each() to retrieve
>> the id of a peer netns. Note that it will be possible to add a table (struct net
>> -> id) later to optimize this lookup if needed.
>>
>> Patch 1/4 introduces the netlink API mechanism to set and get these ids.
>> Patch 2/4 and 3/4 implements an example of how to use these ids in rtnetlink
>> messages. And patch 4/4 shows that the netlink messages can be symetric between
>> a GET and a SET.
>>
>> iproute2 patches are available, I can send them on demand.
> 
> A quick reply.  I think this patchset is in the right general direction.
> There are some oddball details that seem odd/awkward to me such as using
> genetlink instead of rtnetlink to get and set the ids, and not having
> ids if they are not set (that feels like a maintenance/usability challenge).
> 
> I would like to give your patches a deep review, but I won't be able to
> do that for a couple of weeks.  I am deep in the process of moving,
> and will be mostly offline until about the Nov 11th.

I'm going to mark this patch set 'deferred' in patchwork until things
move forward.

Thanks.