switchdev: fix stp update API to work with layered netdevices

make it same as the netdev_switch_port_bridge_setlink/dellink
api (ie traverse lowerdevs to get to the switch port).

removes "WARN_ON(!ops->ndo_switch_parent_id_get)" because
direct bridge ports can be stacked netdevices (like bonds
and team of switch ports) which may not implement this ndo.

v2 to v3:
	- remove changes to bond and team. Bring back the
	transparently following lowerdevs like i initially
	had for setlink/getlink
	(http://www.spinics.net/lists/netdev/msg313436.html)
	dave and scott feldman also seem to prefer it be that
	way and move to non-transparent way of doing things
	if we see a problem down the lane.

v3 to v4:
	- fix ret initialization

v4 to v5:
	- return err on first failure (scott feldman)

v5 to v6:
	- change variable name (err) and initialize to
	-EOPNOTSUPP (scott feldman).

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Acked-by: Scott Feldman <sfeldma@gmail.com>
Acked-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/switchdev/switchdev.c b/net/switchdev/switchdev.c
index c9bfa004abed1b7d5a47b9bf509eabce32ad956c..46568b85c3339f57a0d6835e82eff4b67c3ba326 100644 (file)
--- a/net/switchdev/switchdev.c
+++ b/net/switchdev/switchdev.c
@@ -47,11 +47,20 @@ EXPORT_SYMBOL_GPL(netdev_switch_parent_id_get);
 int netdev_switch_port_stp_update(struct net_device *dev, u8 state)
 {
        const struct swdev_ops *ops = dev->swdev_ops;
+       struct net_device *lower_dev;
+       struct list_head *iter;
+       int err = -EOPNOTSUPP;
 
-       if (!ops || !ops->swdev_port_stp_update)
-               return -EOPNOTSUPP;
-       WARN_ON(!ops->swdev_parent_id_get);
-       return ops->swdev_port_stp_update(dev, state);
+       if (ops && ops->swdev_port_stp_update)
+               return ops->swdev_port_stp_update(dev, state);
+
+       netdev_for_each_lower_dev(dev, lower_dev, iter) {
+               err = netdev_switch_port_stp_update(lower_dev, state);
+               if (err && err != -EOPNOTSUPP)
+                       return err;
+       }
+
+       return err;
 }
 EXPORT_SYMBOL_GPL(netdev_switch_port_stp_update);