On Mon, 10 Sep 2018 13:16:01 +0300
Nikolay Aleksandrov <nikolay@xxxxxxxxxxxxxxxxxxx> wrote:
> Add support for entries which are "sticky", i.e. will not change their port
> if they show up from a different one. A new ndm flag is introduced for that
> purpose - NTF_STICKY. We allow to set it only to non-local entries.
Is there a name for this in other network switch API's?
>
> Signed-off-by: Nikolay Aleksandrov <nikolay@xxxxxxxxxxxxxxxxxxx>
> ---
> I'll send the selftest for sticky with the iproute2 patch if this one is
> accepted. We've had multiple requests to support such flag and now it's
> also needed for some eVPN and clag setups.
>
> include/uapi/linux/neighbour.h | 1 +
> net/bridge/br_fdb.c | 19 ++++++++++++++++---
> net/bridge/br_private.h | 1 +
> 3 files changed, 18 insertions(+), 3 deletions(-)
>
> diff --git a/include/uapi/linux/neighbour.h b/include/uapi/linux/neighbour.h
> index 904db6148476..998155444e0d 100644
> --- a/include/uapi/linux/neighbour.h
> +++ b/include/uapi/linux/neighbour.h
> @@ -43,6 +43,7 @@ enum {
> #define NTF_PROXY 0x08 /* == ATF_PUBL */
> #define NTF_EXT_LEARNED 0x10
> #define NTF_OFFLOADED 0x20
> +#define NTF_STICKY 0x40
> #define NTF_ROUTER 0x80
>
> /*
> diff --git a/net/bridge/br_fdb.c b/net/bridge/br_fdb.c
> index 502f66349530..26569ed06a4d 100644
> --- a/net/bridge/br_fdb.c
> +++ b/net/bridge/br_fdb.c
> @@ -584,7 +584,7 @@ void br_fdb_update(struct net_bridge *br, struct net_bridge_port *source,
> unsigned long now = jiffies;
>
> /* fastpath: update of existing entry */
> - if (unlikely(source != fdb->dst)) {
> + if (unlikely(source != fdb->dst && !fdb->is_sticky)) {
> fdb->dst = source;
> fdb_modified = true;
> /* Take over HW learned entry */
> @@ -656,6 +656,8 @@ static int fdb_fill_info(struct sk_buff *skb, const struct net_bridge *br,
> ndm->ndm_flags |= NTF_OFFLOADED;
> if (fdb->added_by_external_learn)
> ndm->ndm_flags |= NTF_EXT_LEARNED;
> + if (fdb->is_sticky)
> + ndm->ndm_flags |= NTF_STICKY;
>
> if (nla_put(skb, NDA_LLADDR, ETH_ALEN, &fdb->key.addr))
> goto nla_put_failure;
> @@ -772,7 +774,8 @@ int br_fdb_dump(struct sk_buff *skb,
>
> /* Update (create or replace) forwarding database entry */
> static int fdb_add_entry(struct net_bridge *br, struct net_bridge_port *source,
> - const __u8 *addr, __u16 state, __u16 flags, __u16 vid)
> + const u8 *addr, u16 state, u16 flags, u16 vid,
> + u8 is_sticky)
Why not change the API to take a full ndm flags, someone is sure to add more later.
