[RFC PATCH net-next 3/3] net: dsa: refine netdev event notifier

From: Vivien Didelot
Date: Sun Mar 13 2016 - 01:43:40 EST


Rework the netdev event handler, similar to what the Mellanox Spectrum
driver does, to eventually welcome NETDEV_PRECHANGEUPPER actions and use
netdev helpers, such as netif_is_bridge_master.

Signed-off-by: Vivien Didelot <vivien.didelot@xxxxxxxxxxxxxxxxxxxx>
---
net/dsa/slave.c | 55 +++++++++++++++++++++++++++++++------------------------
1 file changed, 31 insertions(+), 24 deletions(-)

diff --git a/net/dsa/slave.c b/net/dsa/slave.c
index 54976c4..27f7886 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)
@@ -1139,40 +1139,47 @@ 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_PRECHANGEUPPER:
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;
}
--
2.7.2