Re: [PATCH v2 net-next 2/4] net: switchdev: add support for offloading of fdb locked flag

[Vladimir Oltean <olteanv@gmail.com>]

On Wed, Mar 23, 2022 at 01:29:52PM +0100, Hans Schultz wrote:
> On tor, mar 17, 2022 at 10:39, Hans Schultz <schultz.hans@gmail.com> wrote:
> > Used for Mac-auth/MAB feature in the offloaded case.
> >
> > Signed-off-by: Hans Schultz <schultz.hans+netdev@gmail.com>
> > ---
> >  include/net/switchdev.h | 3 ++-
> >  net/bridge/br.c         | 3 ++-
> >  net/bridge/br_fdb.c     | 7 +++++--
> >  net/bridge/br_private.h | 2 +-
> >  4 files changed, 10 insertions(+), 5 deletions(-)
> >
> > diff --git a/include/net/switchdev.h b/include/net/switchdev.h
> > index 3e424d40fae3..d5d923411f5e 100644
> > --- a/include/net/switchdev.h
> > +++ b/include/net/switchdev.h
> > @@ -229,7 +229,8 @@ struct switchdev_notifier_fdb_info {
> >  	u16 vid;
> >  	u8 added_by_user:1,
> >  	   is_local:1,
> > -	   offloaded:1;
> > +	   offloaded:1,
> > +	   locked:1;
> >  };
> >  
> >  struct switchdev_notifier_port_obj_info {
> > diff --git a/net/bridge/br.c b/net/bridge/br.c
> > index b1dea3febeea..adcdbecbc218 100644
> > --- a/net/bridge/br.c
> > +++ b/net/bridge/br.c
> > @@ -166,7 +166,8 @@ static int br_switchdev_event(struct notifier_block *unused,
> >  	case SWITCHDEV_FDB_ADD_TO_BRIDGE:
> >  		fdb_info = ptr;
> >  		err = br_fdb_external_learn_add(br, p, fdb_info->addr,
> > -						fdb_info->vid, false);
> > +						fdb_info->vid, false,
> > +						fdb_info->locked);
> >  		if (err) {
> >  			err = notifier_from_errno(err);
> >  			break;
> > diff --git a/net/bridge/br_fdb.c b/net/bridge/br_fdb.c
> > index 57ec559a85a7..57aa1955d34d 100644
> > --- a/net/bridge/br_fdb.c
> > +++ b/net/bridge/br_fdb.c
> > @@ -987,7 +987,7 @@ static int __br_fdb_add(struct ndmsg *ndm, struct net_bridge *br,
> >  					   "FDB entry towards bridge must be permanent");
> >  			return -EINVAL;
> >  		}
> > -		err = br_fdb_external_learn_add(br, p, addr, vid, true);
> > +		err = br_fdb_external_learn_add(br, p, addr, vid, true,
> >  false);
> 
> Does someone have an idea why there at this point is no option to add a
> dynamic fdb entry?
> 
> The fdb added entries here do not age out, while the ATU entries do
> (after 5 min), resulting in unsynced ATU vs fdb.

I think the expectation is to use br_fdb_external_learn_del() if the
externally learned entry expires. The bridge should not age by itself
FDB entries learned externally.

> >  	} else {
> >  		spin_lock_bh(&br->hash_lock);
> >  		err = fdb_add_entry(br, p, addr, ndm, nlh_flags, vid, nfea_tb);
> > @@ -1216,7 +1216,7 @@ void br_fdb_unsync_static(struct net_bridge *br, struct net_bridge_port *p)
> >  
> >  int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p,
> >  			      const unsigned char *addr, u16 vid,
> > -			      bool swdev_notify)
> > +			      bool swdev_notify, bool locked)
> >  {
> >  	struct net_bridge_fdb_entry *fdb;
> >  	bool modified = false;
> > @@ -1236,6 +1236,9 @@ int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p,
> >  		if (!p)
> >  			flags |= BIT(BR_FDB_LOCAL);
> >  
> > +		if (locked)
> > +			flags |= BIT(BR_FDB_ENTRY_LOCKED);
> > +
> >  		fdb = fdb_create(br, p, addr, vid, flags);
> >  		if (!fdb) {
> >  			err = -ENOMEM;
> > diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
> > index f5a0b68c4857..3275e33b112f 100644
> > --- a/net/bridge/br_private.h
> > +++ b/net/bridge/br_private.h
> > @@ -790,7 +790,7 @@ int br_fdb_sync_static(struct net_bridge *br, struct net_bridge_port *p);
> >  void br_fdb_unsync_static(struct net_bridge *br, struct net_bridge_port *p);
> >  int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p,
> >  			      const unsigned char *addr, u16 vid,
> > -			      bool swdev_notify);
> > +			      bool swdev_notify, bool locked);
> >  int br_fdb_external_learn_del(struct net_bridge *br, struct net_bridge_port *p,
> >  			      const unsigned char *addr, u16 vid,
> >  			      bool swdev_notify);
> > -- 
> > 2.30.2