net: bridge: ignore switchdev events for LAG ports which didn't request replay

There is a slight inconvenience in the switchdev replay helpers added
recently, and this is when:

ip link add br0 type bridge
ip link add bond0 type bond
ip link set bond0 master br0
bridge vlan add dev bond0 vid 100
ip link set swp0 master bond0
ip link set swp1 master bond0

Since the underlying driver (currently only DSA) asks for a replay of
VLANs when swp0 and swp1 join the LAG because it is bridged, what will
happen is that DSA will try to react twice on the VLAN event for swp0.
This is not really a huge problem right now, because most drivers accept
duplicates since the bridge itself does, but it will become a problem
when we add support for replaying switchdev object deletions.

Let's fix this by adding a blank void *ctx in the replay helpers, which
will be passed on by the bridge in the switchdev notifications. If the
context is NULL, everything is the same as before. But if the context is
populated with a valid pointer, the underlying switchdev driver
(currently DSA) can use the pointer to 'see through' the bridge port
(which in the example above is bond0) and 'know' that the event is only
for a particular physical port offloading that bridge port, and not for
all of them.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 17 insertions, 2 deletions

diff --git a/drivers/net/ethernet/mscc/ocelot_net.c b/drivers/net/ethernet/mscc/ocelot_net.c
index 456541640feb..166d851962d2 100644
--- a/drivers/net/ethernet/mscc/ocelot_net.c
+++ b/drivers/net/ethernet/mscc/ocelot_net.c
@@ -948,6 +948,9 @@ static int ocelot_port_attr_set(struct net_device *dev, const void *ctx,
 	int port = priv->chip_port;
 	int err = 0;
 
+	if (ctx && ctx != priv)
+		return 0;
+
 	switch (attr->id) {
 	case SWITCHDEV_ATTR_ID_PORT_STP_STATE:
 		ocelot_port_attr_stp_state_set(ocelot, port, attr->u.stp_state);
@@ -1062,8 +1065,12 @@ static int ocelot_port_obj_add(struct net_device *dev, const void *ctx,
 			       const struct switchdev_obj *obj,
 			       struct netlink_ext_ack *extack)
 {
+	struct ocelot_port_private *priv = netdev_priv(dev);
 	int ret = 0;
 
+	if (ctx && ctx != priv)
+		return 0;
+
 	switch (obj->id) {
 	case SWITCHDEV_OBJ_ID_PORT_VLAN:
 		ret = ocelot_port_obj_add_vlan(dev,
@@ -1089,8 +1096,12 @@ static int ocelot_port_obj_add(struct net_device *dev, const void *ctx,
 static int ocelot_port_obj_del(struct net_device *dev, const void *ctx,
 			       const struct switchdev_obj *obj)
 {
+	struct ocelot_port_private *priv = netdev_priv(dev);
 	int ret = 0;
 
+	if (ctx && ctx != priv)
+		return 0;
+
 	switch (obj->id) {
 	case SWITCHDEV_OBJ_ID_PORT_VLAN:
 		ret = ocelot_vlan_vid_del(dev,
@@ -1143,10 +1154,14 @@ static int ocelot_switchdev_sync(struct ocelot *ocelot, int port,
 				 struct net_device *bridge_dev,
 				 struct netlink_ext_ack *extack)
 {
+	struct ocelot_port *ocelot_port = ocelot->ports[port];
+	struct ocelot_port_private *priv;
 	clock_t ageing_time;
 	u8 stp_state;
 	int err;
 
+	priv = container_of(ocelot_port, struct ocelot_port_private, port);
+
 	ocelot_inherit_brport_flags(ocelot, port, brport_dev);
 
 	stp_state = br_port_get_stp_state(brport_dev);
@@ -1160,12 +1175,12 @@ static int ocelot_switchdev_sync(struct ocelot *ocelot, int port,
 	ageing_time = br_get_ageing_time(bridge_dev);
 	ocelot_port_attr_ageing_set(ocelot, port, ageing_time);
 
-	err = br_mdb_replay(bridge_dev, brport_dev,
+	err = br_mdb_replay(bridge_dev, brport_dev, priv,
 			    &ocelot_switchdev_blocking_nb, extack);
 	if (err && err != -EOPNOTSUPP)
 		return err;
 
-	err = br_vlan_replay(bridge_dev, brport_dev,
+	err = br_vlan_replay(bridge_dev, brport_dev, priv,
 			     &ocelot_switchdev_blocking_nb, extack);
 	if (err && err != -EOPNOTSUPP)
 		return err;