Re: [PATCH v2 net-next 2/7] rtnetlink: Add peer_type in struct rtnl_link_ops.

[Nikolay Aleksandrov <razor@blackwall.org>]

On Tue, Nov 05, 2024 at 06:24:27PM -0800, Kuniyuki Iwashima wrote:
> In ops->newlink(), veth, vxcan, and netkit call rtnl_link_get_net() with
> a net pointer, which is the first argument of ->newlink().
> 
> rtnl_link_get_net() could return another netns based on IFLA_NET_NS_PID
> and IFLA_NET_NS_FD in the peer device's attributes.
> 
> We want to get it and fill rtnl_nets->nets[] in advance in rtnl_newlink()
> for per-netns RTNL.
> 
> All of the three get the peer netns in the same way:
> 
>   1. Call rtnl_nla_parse_ifinfomsg()
>   2. Call ops->validate() (vxcan doesn't have)
>   3. Call rtnl_link_get_net()
> 
> Let's add a new field peer_type to struct rtnl_link_ops and prefetch
> netns in the peer ifla to add it to rtnl_nets in rtnl_newlink().
> 
> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
> Reviewed-by: Eric Dumazet <edumazet@google.com>
> ---
> v2:
>   * Rename the helper to rtnl_link_get_net_ifla()
>   * Unexport rtnl_link_get_net_ifla() and made it static
>   * Change peer_type to u16
>   * squash patch 2 & 3 (due to static requires a user)
> ---
>  include/net/rtnetlink.h |  2 ++
>  net/core/rtnetlink.c    | 55 ++++++++++++++++++++++++++++++++++++++---
>  2 files changed, 53 insertions(+), 4 deletions(-)
> 
 
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>