[PATCH v4 net-next 09/11] net: dsa: sync up switchdev objects and port attributes when joining the bridge

[Vladimir Oltean <olteanv@xxxxxxxxx>]

From: Vladimir Oltean <vladimir.oltean@xxxxxxx>

If we join an already-created bridge port, such as a bond master
interface, then we can miss the initial switchdev notifications emitted
by the bridge for this port, while it wasn't offloaded by anybody.

Signed-off-by: Vladimir Oltean <vladimir.oltean@xxxxxxx>
---
 net/dsa/dsa_priv.h |  3 +++
 net/dsa/port.c     | 46 ++++++++++++++++++++++++++++++++++++++++++++++
 net/dsa/slave.c    |  4 ++--
 3 files changed, 51 insertions(+), 2 deletions(-)

diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h
index b8778c5d8529..92282de54230 100644
--- a/net/dsa/dsa_priv.h
+++ b/net/dsa/dsa_priv.h
@@ -262,6 +262,9 @@ static inline bool dsa_tree_offloads_bridge_port(struct dsa_switch_tree *dst,
 
 /* slave.c */
 extern const struct dsa_device_ops notag_netdev_ops;
+extern struct notifier_block dsa_slave_switchdev_notifier;
+extern struct notifier_block dsa_slave_switchdev_blocking_notifier;
+
 void dsa_slave_mii_bus_init(struct dsa_switch *ds);
 int dsa_slave_create(struct dsa_port *dp);
 void dsa_slave_destroy(struct net_device *slave_dev);
diff --git a/net/dsa/port.c b/net/dsa/port.c
index c712bf3da0a0..01e30264b25b 100644
--- a/net/dsa/port.c
+++ b/net/dsa/port.c
@@ -170,12 +170,46 @@ static void dsa_port_clear_brport_flags(struct dsa_port *dp)
 static int dsa_port_switchdev_sync(struct dsa_port *dp,
 				   struct netlink_ext_ack *extack)
 {
+	struct net_device *brport_dev = dsa_port_to_bridge_port(dp);
+	struct net_device *br = dp->bridge_dev;
 	int err;
 
 	err = dsa_port_inherit_brport_flags(dp, extack);
 	if (err)
 		return err;
 
+	err = dsa_port_set_state(dp, br_port_get_stp_state(brport_dev));
+	if (err && err != -EOPNOTSUPP)
+		return err;
+
+	err = dsa_port_vlan_filtering(dp, br_vlan_enabled(br), extack);
+	if (err && err != -EOPNOTSUPP)
+		return err;
+
+	err = dsa_port_mrouter(dp->cpu_dp, br_multicast_router(br), extack);
+	if (err && err != -EOPNOTSUPP)
+		return err;
+
+	err = dsa_port_ageing_time(dp, br_get_ageing_time(br));
+	if (err && err != -EOPNOTSUPP)
+		return err;
+
+	err = br_mdb_replay(br, brport_dev,
+			    &dsa_slave_switchdev_blocking_notifier,
+			    extack);
+	if (err && err != -EOPNOTSUPP)
+		return err;
+
+	err = br_fdb_replay(br, brport_dev, &dsa_slave_switchdev_notifier);
+	if (err && err != -EOPNOTSUPP)
+		return err;
+
+	err = br_vlan_replay(br, brport_dev,
+			     &dsa_slave_switchdev_blocking_notifier,
+			     extack);
+	if (err && err != -EOPNOTSUPP)
+		return err;
+
 	return 0;
 }
 
@@ -198,6 +232,18 @@ static void dsa_port_switchdev_unsync(struct dsa_port *dp)
 	 * so allow it to be in BR_STATE_FORWARDING to be kept functional
 	 */
 	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);
+
+	/* Ageing time may be global to the switch chip, so don't change it
+	 * here because we have no good reason (or value) to change it to.
+	 */
 }
 
 int dsa_port_bridge_join(struct dsa_port *dp, struct net_device *br,
diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index 1ff48be476bb..c51e52418a62 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -2392,11 +2392,11 @@ static struct notifier_block dsa_slave_nb __read_mostly = {
 	.notifier_call  = dsa_slave_netdevice_event,
 };
 
-static struct notifier_block dsa_slave_switchdev_notifier = {
+struct notifier_block dsa_slave_switchdev_notifier = {
 	.notifier_call = dsa_slave_switchdev_event,
 };
 
-static struct notifier_block dsa_slave_switchdev_blocking_notifier = {
+struct notifier_block dsa_slave_switchdev_blocking_notifier = {
 	.notifier_call = dsa_slave_switchdev_blocking_event,
 };
 
-- 
2.25.1