• Nicolas Dichtel's avatar
    netlink: allow to listen "all" netns · 59324cf3
    Nicolas Dichtel authored
    More accurately, listen all netns that have a nsid assigned into the netns
    where the netlink socket is opened.
    For this purpose, a netlink socket option is added:
    NETLINK_LISTEN_ALL_NSID. When this option is set on a netlink socket, this
    socket will receive netlink notifications from all netns that have a nsid
    assigned into the netns where the socket has been opened. The nsid is sent
    to userland via an anscillary data.
    
    With this patch, a daemon needs only one socket to listen many netns. This
    is useful when the number of netns is high.
    
    Because 0 is a valid value for a nsid, the field nsid_is_set indicates if
    the field nsid is valid or not. skb->cb is initialized to 0 on skb
    allocation, thus we are sure that we will never send a nsid 0 by error to
    the userland.
    Signed-off-by: default avatarNicolas Dichtel <nicolas.dichtel@6wind.com>
    Acked-by: default avatarThomas Graf <tgraf@suug.ch>
    Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
    59324cf3
net_namespace.c 22.6 KB