[PATCH net] net: dsa: apply MTU normalization for ports that join a LAG under a bridge too

[Vladimir Oltean <vladimir.oltean@nxp.com>]

We want the MTU normalization logic to apply each time
dsa_port_bridge_join is called, so instead of chasing all callers of
that function, we should move the call within the bridge_join function
itself.

Fixes: 185c9a760a61 ("net: dsa: call dsa_port_bridge_join when joining a LAG that is already in a bridge")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
---
 net/dsa/dsa_priv.h | 1 +
 net/dsa/port.c     | 2 ++
 net/dsa/slave.c    | 4 +---
 3 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/net/dsa/dsa_priv.h b/net/dsa/dsa_priv.h
index 6988066d937f..6e01e796920f 100644
--- a/net/dsa/dsa_priv.h
+++ b/net/dsa/dsa_priv.h
@@ -325,6 +325,7 @@ int dsa_slave_register_notifier(void);
 void dsa_slave_unregister_notifier(void);
 void dsa_slave_setup_tagger(struct net_device *slave);
 int dsa_slave_change_mtu(struct net_device *dev, int new_mtu);
+void dsa_bridge_mtu_normalization(struct dsa_port *dp);
 
 static inline struct dsa_port *dsa_slave_to_port(const struct net_device *dev)
 {
diff --git a/net/dsa/port.c b/net/dsa/port.c
index b6208eecdf4b..eedd9881e1ba 100644
--- a/net/dsa/port.c
+++ b/net/dsa/port.c
@@ -386,6 +386,8 @@ int dsa_port_bridge_join(struct dsa_port *dp, struct net_device *br,
 	if (err)
 		goto out_rollback_unoffload;
 
+	dsa_bridge_mtu_normalization(dp);
+
 	return 0;
 
 out_rollback_unoffload:
diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index b08b2c70702d..124e01ca3312 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -1456,7 +1456,7 @@ static void dsa_hw_port_list_free(struct list_head *hw_port_list)
 }
 
 /* Make the hardware datapath to/from @dev limited to a common MTU */
-static void dsa_bridge_mtu_normalization(struct dsa_port *dp)
+void dsa_bridge_mtu_normalization(struct dsa_port *dp)
 {
 	struct list_head hw_port_list;
 	struct dsa_switch_tree *dst;
@@ -2013,8 +2013,6 @@ static int dsa_slave_changeupper(struct net_device *dev,
 	if (netif_is_bridge_master(info->upper_dev)) {
 		if (info->linking) {
 			err = dsa_port_bridge_join(dp, info->upper_dev, extack);
-			if (!err)
-				dsa_bridge_mtu_normalization(dp);
 			err = notifier_from_errno(err);
 		} else {
 			dsa_port_bridge_leave(dp, info->upper_dev);
-- 
2.25.1