Re: [PATCH net-next v2 2/7] net: switchdev: support static FDB addresses

[Vivien Didelot <vivien.didelot@savoirfairelinux.com>]

On 15-08-05 23:28:15, Scott Feldman wrote:
> On Wed, Aug 5, 2015 at 10:44 PM, Vivien Didelot
> <vivien.didelot@savoirfairelinux.com> wrote:
> > This patch adds a is_static boolean to the switchdev_obj_fdb structure,
> > in order to set the ndm_state to either NUD_NOARP or NUD_REACHABLE.
> >
> > Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
> > ---
> >  include/net/switchdev.h   | 1 +
> >  net/switchdev/switchdev.c | 2 +-
> >  2 files changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/include/net/switchdev.h b/include/net/switchdev.h
> > index e90e1a0..0e296b8 100644
> > --- a/include/net/switchdev.h
> > +++ b/include/net/switchdev.h
> > @@ -72,6 +72,7 @@ struct switchdev_obj {
> >                 struct switchdev_obj_fdb {              /* PORT_FDB */
> >                         u8 addr[ETH_ALEN];
> >                         u16 vid;
> > +                       bool is_static;
> 
> What do you think about changing this to u16 ndm_state?  That way, it
> can be used on input (fdb add) and output (fdb dump), and the driver
> can privately track the state, kind of like how the bridge keeps
> is_static, is_local, etc.

I'm OK with the change. Should we consider NUD_NONE (0) a valid value?

> >                 } fdb;
> >         } u;
> >  };
> > diff --git a/net/switchdev/switchdev.c b/net/switchdev/switchdev.c
> > index 9db87a3..e9d1cac 100644
> > --- a/net/switchdev/switchdev.c
> > +++ b/net/switchdev/switchdev.c
> > @@ -811,7 +811,7 @@ static int switchdev_port_fdb_dump_cb(struct net_device *dev,
> >         ndm->ndm_flags   = NTF_SELF;
> >         ndm->ndm_type    = 0;
> >         ndm->ndm_ifindex = dev->ifindex;
> > -       ndm->ndm_state   = NUD_REACHABLE;
> > +       ndm->ndm_state   = obj->u.fdb.is_static ? NUD_NOARP : NUD_REACHABLE;

In other word, do we prefer this:

    ndm->ndm_state = obj->u.fdb.ndm_state == NUD_NONE ?
                     NUD_REACHABLE : obj->u.fdb.ndm_state;

Or this (meaning switchdev users cannot leave it blank and must at least
set NUD_REACHABLE themselves):

    ndm->ndm_state = obj->u.fdb.ndm_state;

Thanks,
-v