mlxsw: spectrum: Allow event handlers to check unowned bridges

Currently the bridge-related handlers bail out when the event is related to
a netdevice that is not an upper of one of the front-panel ports. In order
to allow enslavement of front-panel ports to bridges that already have
uppers, it will be necessary to replay CHANGEUPPER events to validate that
the configuration is offloadable. In order for the replay to be effective,
it must be possible to ignore unsupported configuration in the context of
an actual notifier event, but to still "veto" these configurations when the
validation is performed.

To that end, introduce two parameters to a number of handlers: mlxsw_sp,
because it will not be possible to deduce that from the netdevice lowers;
and process_foreign to indicate whether netdevices that are not front panel
uppers should be validated.
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Danielle Ratson <danieller@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/spectrum.c

@@ -4936,17 +4936,17 @@ static int mlxsw_sp_netdevice_lag_port_vlan_event(struct net_device *vlan_dev,
 	return 0;
 }
 
-static int mlxsw_sp_netdevice_bridge_vlan_event(struct net_device *vlan_dev,
+static int mlxsw_sp_netdevice_bridge_vlan_event(struct mlxsw_sp *mlxsw_sp,
+						struct net_device *vlan_dev,
 						struct net_device *br_dev,
 						unsigned long event, void *ptr,
-						u16 vid)
+						u16 vid, bool process_foreign)
 {
-	struct mlxsw_sp *mlxsw_sp = mlxsw_sp_lower_get(vlan_dev);
 	struct netdev_notifier_changeupper_info *info = ptr;
 	struct netlink_ext_ack *extack;
 	struct net_device *upper_dev;
 
-	if (!mlxsw_sp)
+	if (!process_foreign && !mlxsw_sp_lower_get(vlan_dev))
 		return 0;
 
 	extack = netdev_notifier_info_to_extack(&info->info);
@@ -4979,8 +4979,10 @@ static int mlxsw_sp_netdevice_bridge_vlan_event(struct net_device *vlan_dev,
 	return 0;
 }
 
-static int mlxsw_sp_netdevice_vlan_event(struct net_device *vlan_dev,
-					 unsigned long event, void *ptr)
+static int mlxsw_sp_netdevice_vlan_event(struct mlxsw_sp *mlxsw_sp,
+					 struct net_device *vlan_dev,
+					 unsigned long event, void *ptr,
+					 bool process_foreign)
 {
 	struct net_device *real_dev = vlan_dev_real_dev(vlan_dev);
 	u16 vid = vlan_dev_vlan_id(vlan_dev);
@@ -4993,22 +4995,25 @@ static int mlxsw_sp_netdevice_vlan_event(struct net_device *vlan_dev,
 							      real_dev, event,
 							      ptr, vid);
 	else if (netif_is_bridge_master(real_dev))
-		return mlxsw_sp_netdevice_bridge_vlan_event(vlan_dev, real_dev,
-							    event, ptr, vid);
+		return mlxsw_sp_netdevice_bridge_vlan_event(mlxsw_sp, vlan_dev,
+							    real_dev, event,
+							    ptr, vid,
+							    process_foreign);
 
 	return 0;
 }
 
-static int mlxsw_sp_netdevice_bridge_event(struct net_device *br_dev,
-					   unsigned long event, void *ptr)
+static int mlxsw_sp_netdevice_bridge_event(struct mlxsw_sp *mlxsw_sp,
+					   struct net_device *br_dev,
+					   unsigned long event, void *ptr,
+					   bool process_foreign)
 {
-	struct mlxsw_sp *mlxsw_sp = mlxsw_sp_lower_get(br_dev);
 	struct netdev_notifier_changeupper_info *info = ptr;
 	struct netlink_ext_ack *extack;
 	struct net_device *upper_dev;
 	u16 proto;
 
-	if (!mlxsw_sp)
+	if (!process_foreign && !mlxsw_sp_lower_get(br_dev))
 		return 0;
 
 	extack = netdev_notifier_info_to_extack(&info->info);
@@ -5147,7 +5152,8 @@ static int mlxsw_sp_netdevice_vxlan_event(struct mlxsw_sp *mlxsw_sp,
 }
 
 static int __mlxsw_sp_netdevice_event(struct mlxsw_sp *mlxsw_sp,
-				      unsigned long event, void *ptr)
+				      unsigned long event, void *ptr,
+				      bool process_foreign)
 {
 	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
 	struct mlxsw_sp_span_entry *span_entry;
@@ -5166,9 +5172,11 @@ static int __mlxsw_sp_netdevice_event(struct mlxsw_sp *mlxsw_sp,
 	else if (netif_is_lag_master(dev))
 		err = mlxsw_sp_netdevice_lag_event(dev, event, ptr);
 	else if (is_vlan_dev(dev))
-		err = mlxsw_sp_netdevice_vlan_event(dev, event, ptr);
+		err = mlxsw_sp_netdevice_vlan_event(mlxsw_sp, dev, event, ptr,
+						    process_foreign);
 	else if (netif_is_bridge_master(dev))
-		err = mlxsw_sp_netdevice_bridge_event(dev, event, ptr);
+		err = mlxsw_sp_netdevice_bridge_event(mlxsw_sp, dev, event, ptr,
+						      process_foreign);
 	else if (netif_is_macvlan(dev))
 		err = mlxsw_sp_netdevice_macvlan_event(dev, event, ptr);
 
@@ -5183,7 +5191,7 @@ static int mlxsw_sp_netdevice_event(struct notifier_block *nb,
 
 	mlxsw_sp = container_of(nb, struct mlxsw_sp, netdevice_nb);
 	mlxsw_sp_span_respin(mlxsw_sp);
-	err = __mlxsw_sp_netdevice_event(mlxsw_sp, event, ptr);
+	err = __mlxsw_sp_netdevice_event(mlxsw_sp, event, ptr, false);
 
 	return notifier_from_errno(err);
 }