[PATCH net-next v3] switchdev: fix stp update API to work with layered netdevices

[PATCH net-next v3] switchdev: fix stp update API to work with layered netdevices

[roopa]

From: Roopa Prabhu <roopa@cumulusnetworks.com>

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 imeplement 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.

Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
---
 net/switchdev/switchdev.c |   20 ++++++++++++++++----
 1 file changed, 16 insertions(+), 4 deletions(-)

diff --git a/net/switchdev/switchdev.c b/net/switchdev/switchdev.c
index c9bfa00..5c53951 100644
--- a/net/switchdev/switchdev.c
+++ b/net/switchdev/switchdev.c
@@ -47,11 +47,23 @@ 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 ret = 0, 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 (!(dev->features & NETIF_F_HW_SWITCH_OFFLOAD))
+		return ret;
+
+	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)
+			ret = err;
+	}
+
+	return ret;
 }
 EXPORT_SYMBOL_GPL(netdev_switch_port_stp_update);
 
-- 
1.7.10.4

Re: [PATCH net-next v3] switchdev: fix stp update API to work with layered netdevices

[Jiri Pirko]

Mon, Mar 16, 2015 at 04:01:39PM CET, roopa@cumulusnetworks.com wrote:
>From: Roopa Prabhu <roopa@cumulusnetworks.com>
>
>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 imeplement 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.
>
>Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
>---
> net/switchdev/switchdev.c |   20 ++++++++++++++++----
> 1 file changed, 16 insertions(+), 4 deletions(-)
>
>diff --git a/net/switchdev/switchdev.c b/net/switchdev/switchdev.c
>index c9bfa00..5c53951 100644
>--- a/net/switchdev/switchdev.c
>+++ b/net/switchdev/switchdev.c
>@@ -47,11 +47,23 @@ 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 ret = 0, err = -EOPNOTSUPP;

	No need to initialize err.

> 
>-	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 (!(dev->features & NETIF_F_HW_SWITCH_OFFLOAD))
>+		return ret;
		Just flat "0" might be nicer here.

>+
>+	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)
>+			ret = err;
>+	}
>+
>+	return ret;


Do we want to return 0 in case no lower dev is there? -EOPNOTSUPP seems
to make more sense to me in that case.



> }
> EXPORT_SYMBOL_GPL(netdev_switch_port_stp_update);
> 
>-- 
>1.7.10.4
>

Re: [PATCH net-next v3] switchdev: fix stp update API to work with layered netdevices

[roopa]

On 3/16/15, 8:42 AM, Jiri Pirko wrote:
> Mon, Mar 16, 2015 at 04:01:39PM CET, roopa@cumulusnetworks.com wrote:
>> From: Roopa Prabhu <roopa@cumulusnetworks.com>
>>
>> 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 imeplement 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.
>>
>> Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
>> ---
>> net/switchdev/switchdev.c |   20 ++++++++++++++++----
>> 1 file changed, 16 insertions(+), 4 deletions(-)
>>
>> diff --git a/net/switchdev/switchdev.c b/net/switchdev/switchdev.c
>> index c9bfa00..5c53951 100644
>> --- a/net/switchdev/switchdev.c
>> +++ b/net/switchdev/switchdev.c
>> @@ -47,11 +47,23 @@ 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 ret = 0, err = -EOPNOTSUPP;
> 	No need to initialize err.

ack, i wanted to initialize ret there actually.
>
>> -	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 (!(dev->features & NETIF_F_HW_SWITCH_OFFLOAD))
>> +		return ret;
> 		Just flat "0" might be nicer here.
>
>> +
>> +	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)
>> +			ret = err;
>> +	}
>> +
>> +	return ret;
>
> Do we want to return 0 in case no lower dev is there? -EOPNOTSUPP seems
> to make more sense to me in that case.

yes, that was not intentional. I will fix the ret initialization like i 
intended and that
should take care of it.

thanks for the review.