net: dsa: add port fast ageing

Today the DSA drivers are in charge of flushing the MAC addresses
associated to a port when its STP state changes from Learning or
Forwarding, to Disabled or Blocking or Listening.

This makes the drivers more complex and hides the generic switch logic.
Introduce a new optional port_fast_age operation to dsa_switch_ops, to
move this logic to the DSA layer and keep drivers simple.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 18 insertions, 0 deletions

diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index fd78d4c9b197..6b1282c006b1 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -71,8 +71,26 @@ static inline bool dsa_port_is_bridged(struct dsa_slave_priv *p)
 
 static void dsa_port_set_stp_state(struct dsa_switch *ds, int port, u8 state)
 {
+        struct dsa_port *dp = &ds->ports[port];
+
         if (ds->ops->port_stp_state_set)
                 ds->ops->port_stp_state_set(ds, port, state);
+
+        if (ds->ops->port_fast_age) {
+                /* Fast age FDB entries or flush appropriate forwarding database
+                 * for the given port, if we are moving it from Learning or
+                 * Forwarding state, to Disabled or Blocking or Listening state.
+                 */
+
+                if ((dp->stp_state == BR_STATE_LEARNING ||
+                     dp->stp_state == BR_STATE_FORWARDING) &&
+                    (state == BR_STATE_DISABLED ||
+                     state == BR_STATE_BLOCKING ||
+                     state == BR_STATE_LISTENING))
+                        ds->ops->port_fast_age(ds, port);
+        }
+
+        dp->stp_state = state;
 }
 
 static int dsa_slave_open(struct net_device *dev)