[RFC net-next 5/9] net: dsa: Pass VLAN MST migration notifications to driver

[Tobias Waldekranz]

Add the usual trampoline functionality from the generic DSA layer down
to the drivers for VLAN MST migrations.

Signed-off-by: Tobias Waldekranz <tobias@xxxxxxxxxxxxxx>
---
 include/net/dsa.h    |  3 +++
 net/bridge/br_vlan.c |  2 +-
 net/dsa/dsa_priv.h   |  1 +
 net/dsa/port.c       | 10 ++++++++++
 net/dsa/slave.c      |  6 ++++++
 5 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/include/net/dsa.h b/include/net/dsa.h
index fd1f62a6e0a8..2aabe7f0b176 100644
--- a/include/net/dsa.h
+++ b/include/net/dsa.h
@@ -901,6 +901,9 @@ struct dsa_switch_ops {
 				 struct netlink_ext_ack *extack);
 	int	(*port_vlan_del)(struct dsa_switch *ds, int port,
 				 const struct switchdev_obj_port_vlan *vlan);
+	int	(*vlan_mstid_set)(struct dsa_switch *ds,
+				  const struct switchdev_attr *attr);
+
 	/*
 	 * Forwarding database
 	 */
diff --git a/net/bridge/br_vlan.c b/net/bridge/br_vlan.c
index c45a34c14e10..48b2f5dd277c 100644
--- a/net/bridge/br_vlan.c
+++ b/net/bridge/br_vlan.c
@@ -173,7 +173,7 @@ static int br_vlan_mst_migrate(struct net_bridge_vlan *v, u16 mstid)
 	old_mst = rtnl_dereference(v->mst);
 	rcu_assign_pointer(v->mst, mst);
 
-	if (br_vlan_is_master(v)) {
+	if (!old_mst || br_vlan_is_master(v)) {
 		struct switchdev_attr attr = {
 			.id = SWITCHDEV_ATTR_ID_VLAN_MSTID,
 			.flags = SWITCHDEV_F_DEFER,
diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h
index 2bbfa9efe9f8..43709c005461 100644
--- a/net/dsa/dsa_priv.h
+++ b/net/dsa/dsa_priv.h
@@ -204,6 +204,7 @@ int dsa_port_vlan_filtering(struct dsa_port *dp, bool vlan_filtering,
 			    struct netlink_ext_ack *extack);
 bool dsa_port_skip_vlan_configuration(struct dsa_port *dp);
 int dsa_port_ageing_time(struct dsa_port *dp, clock_t ageing_clock);
+int dsa_port_vlan_mstid(struct dsa_port *dp, const struct switchdev_attr *attr);
 int dsa_port_mtu_change(struct dsa_port *dp, int new_mtu,
 			bool targeted_match);
 int dsa_port_fdb_add(struct dsa_port *dp, const unsigned char *addr,
diff --git a/net/dsa/port.c b/net/dsa/port.c
index bd78192e0e47..4fb2bf2383d9 100644
--- a/net/dsa/port.c
+++ b/net/dsa/port.c
@@ -729,6 +729,16 @@ int dsa_port_bridge_flags(struct dsa_port *dp,
 	return 0;
 }
 
+int dsa_port_vlan_mstid(struct dsa_port *dp, const struct switchdev_attr *attr)
+{
+	struct dsa_switch *ds = dp->ds;
+
+	if (!ds->ops->vlan_mstid_set)
+		return -EOPNOTSUPP;
+
+	return ds->ops->vlan_mstid_set(ds, attr);
+}
+
 int dsa_port_mtu_change(struct dsa_port *dp, int new_mtu,
 			bool targeted_match)
 {
diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index 2f6caf5d037e..0a5e44105add 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -314,6 +314,12 @@ static int dsa_slave_port_attr_set(struct net_device *dev, const void *ctx,
 
 		ret = dsa_port_bridge_flags(dp, attr->u.brport_flags, extack);
 		break;
+	case SWITCHDEV_ATTR_ID_VLAN_MSTID:
+		if (!dsa_port_offloads_bridge_dev(dp, attr->orig_dev))
+			return -EOPNOTSUPP;
+
+		ret = dsa_port_vlan_mstid(dp, attr);
+		break;
 	default:
 		ret = -EOPNOTSUPP;
 		break;
-- 
2.25.1