net: dsa: refine netdev event notifier

Rework the netdev event handler, similar to what the Mellanox Spectrum
driver does, to easily welcome more events later (for example
NETDEV_PRECHANGEUPPER) and use netdev helpers (such as
netif_is_bridge_master).

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 30 insertions, 24 deletions

diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index 8e00f1d83eb8..a575f0350d5a 100644
--- a/net/dsa/slave.c
+++ b/net/dsa/slave.c
@@ -451,7 +451,7 @@ static int dsa_slave_bridge_port_join(struct net_device *dev,
         if (ds->drv->port_bridge_join)
                 ret = ds->drv->port_bridge_join(ds, p->port, br);
 
-        return ret;
+        return ret == -EOPNOTSUPP ? 0 : ret;
 }
 
 static void dsa_slave_bridge_port_leave(struct net_device *dev)
@@ -1143,40 +1143,46 @@ static bool dsa_slave_dev_check(struct net_device *dev)
         return dev->netdev_ops == &dsa_slave_netdev_ops;
 }
 
-static int dsa_slave_master_changed(struct net_device *dev)
+static int dsa_slave_port_upper_event(struct net_device *dev,
+                                      unsigned long event, void *ptr)
 {
-        struct net_device *master = netdev_master_upper_dev_get(dev);
-        struct dsa_slave_priv *p = netdev_priv(dev);
+        struct netdev_notifier_changeupper_info *info = ptr;
+        struct net_device *upper = info->upper_dev;
         int err = 0;
 
-        if (master && master->rtnl_link_ops &&
-            !strcmp(master->rtnl_link_ops->kind, "bridge"))
-                err = dsa_slave_bridge_port_join(dev, master);
-        else if (dsa_port_is_bridged(p))
-                dsa_slave_bridge_port_leave(dev);
+        switch (event) {
+        case NETDEV_CHANGEUPPER:
+                if (netif_is_bridge_master(upper)) {
+                        if (info->linking)
+                                err = dsa_slave_bridge_port_join(dev, upper);
+                        else
+                                dsa_slave_bridge_port_leave(dev);
+                }
 
-        return err;
+                break;
+        }
+
+        return notifier_from_errno(err);
 }
 
-int dsa_slave_netdevice_event(struct notifier_block *unused,
-                              unsigned long event, void *ptr)
+static int dsa_slave_port_event(struct net_device *dev, unsigned long event,
+                                void *ptr)
 {
-        struct net_device *dev;
-        int err = 0;
-
         switch (event) {
         case NETDEV_CHANGEUPPER:
-                dev = netdev_notifier_info_to_dev(ptr);
-                if (!dsa_slave_dev_check(dev))
-                        goto out;
+                return dsa_slave_port_upper_event(dev, event, ptr);
+        }
 
-                err = dsa_slave_master_changed(dev);
-                if (err && err != -EOPNOTSUPP)
-                        netdev_warn(dev, "failed to reflect master change\n");
+        return NOTIFY_DONE;
+}
 
-                break;
-        }
+int dsa_slave_netdevice_event(struct notifier_block *unused,
+                              unsigned long event, void *ptr)
+{
+        struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+
+        if (dsa_slave_dev_check(dev))
+                return dsa_slave_port_event(dev, event, ptr);
 
-out:
         return NOTIFY_DONE;
 }