[PATCH v3 net-next 06/12] net: dsa: sync multicast router state when joining the bridge

[Vladimir Oltean]

From: Vladimir Oltean <vladimir.oltean@xxxxxxx>

Make sure that the multicast router setting of the bridge is picked up
correctly by DSA when joining, regardless of whether there are
sandwiched interfaces or not. The SWITCHDEV_ATTR_ID_BRIDGE_MROUTER port
attribute is only emitted from br_mc_router_state_change.

Signed-off-by: Vladimir Oltean <vladimir.oltean@xxxxxxx>
Reviewed-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
---
Changes in v3:
None.

 net/dsa/port.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/net/dsa/port.c b/net/dsa/port.c
index 3f938c253c99..124f8bb21204 100644
--- a/net/dsa/port.c
+++ b/net/dsa/port.c
@@ -189,6 +189,10 @@ static int dsa_port_switchdev_sync(struct dsa_port *dp,
 	if (err && err != -EOPNOTSUPP)
 		return err;
 
+	err = dsa_port_mrouter(dp->cpu_dp, br_multicast_router(br), extack);
+	if (err && err != -EOPNOTSUPP)
+		return err;
+
 	return 0;
 }
 
@@ -212,6 +216,12 @@ static void dsa_port_switchdev_unsync(struct dsa_port *dp)
 	dsa_port_set_state_now(dp, BR_STATE_FORWARDING);
 
 	/* VLAN filtering is handled by dsa_switch_bridge_leave */
+
+	/* Some drivers treat the notification for having a local multicast
+	 * router by allowing multicast to be flooded to the CPU, so we should
+	 * allow this in standalone mode too.
+	 */
+	dsa_port_mrouter(dp->cpu_dp, true, NULL);
 }
 
 int dsa_port_bridge_join(struct dsa_port *dp, struct net_device *br,
-- 
2.25.1