mlxsw: spectrum: Handle port leaving LAG while bridged

It is possible for a user to remove a port from a LAG device, while the
LAG device or VLAN devices on top of it are bridged. In these cases,
bridge's teardown sequence is never issued, so we need to take care of
it ourselves.

When LAG's unlinking event is received by port netdev:

1) Traverse its vPorts list and make those member in a bridge leave it.
   They will be deleted later by LAG code.

2) Make the port netdev itself leave its bridge if member in one.

Fixes: 0d65fc13042f ("mlxsw: spectrum: Implement LAG port join/leave")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
index ce6845d..637a9d7 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum.c
@@ -2200,10 +2200,14 @@
 	return err;
 }
 
+static int mlxsw_sp_vport_bridge_leave(struct mlxsw_sp_port *mlxsw_sp_vport,
+				       struct net_device *br_dev);
+
 static int mlxsw_sp_port_lag_leave(struct mlxsw_sp_port *mlxsw_sp_port,
 				   struct net_device *lag_dev)
 {
 	struct mlxsw_sp *mlxsw_sp = mlxsw_sp_port->mlxsw_sp;
+	struct mlxsw_sp_port *mlxsw_sp_vport;
 	struct mlxsw_sp_upper *lag;
 	u16 lag_id = mlxsw_sp_port->lag_id;
 	int err;
@@ -2220,6 +2224,29 @@
 	if (err)
 		return err;
 
+	/* In case we leave a LAG device that has bridges built on top,
+	 * then their teardown sequence is never issued and we need to
+	 * invoke the necessary cleanup routines ourselves.
+	 */
+	list_for_each_entry(mlxsw_sp_vport, &mlxsw_sp_port->vports_list,
+			    vport.list) {
+		struct net_device *br_dev;
+
+		if (!mlxsw_sp_vport->bridged)
+			continue;
+
+		br_dev = mlxsw_sp_vport_br_get(mlxsw_sp_vport);
+		mlxsw_sp_vport_bridge_leave(mlxsw_sp_vport, br_dev);
+	}
+
+	if (mlxsw_sp_port->bridged) {
+		mlxsw_sp_port_active_vlans_del(mlxsw_sp_port);
+		mlxsw_sp_port_bridge_leave(mlxsw_sp_port);
+
+		if (lag->ref_count == 1)
+			mlxsw_sp_master_bridge_dec(mlxsw_sp, NULL);
+	}
+
 	if (lag->ref_count == 1) {
 		err = mlxsw_sp_lag_destroy(mlxsw_sp, lag_id);
 		if (err)
@@ -2272,9 +2299,6 @@
 	return mlxsw_sp_port_lag_tx_en_set(mlxsw_sp_port, info->tx_enabled);
 }
 
-static int mlxsw_sp_vport_bridge_leave(struct mlxsw_sp_port *mlxsw_sp_vport,
-				       struct net_device *br_dev);
-
 static int mlxsw_sp_port_vlan_link(struct mlxsw_sp_port *mlxsw_sp_port,
 				   struct net_device *vlan_dev)
 {