[PATCH net-next v4] switchdev: fix stp update API to work with layered netdevices

[PATCH net-next v4] 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.

v3 to v4:
	- fix ret initialization

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..e593b59 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 = -EOPNOTSUPP, 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;
+
+	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 v4] switchdev: fix stp update API to work with layered netdevices

[Jiri Pirko]

Mon, Mar 16, 2015 at 06:32:39PM 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.
>
>v3 to v4:
>	- fix ret initialization
>
>Signed-off-by: Roopa Prabhu <roopa@cumulusnetworks.com>
Acked-by: Jiri Pirko <jiri@resnulli.us>

Thanks Roopa!

Re: [PATCH net-next v4] switchdev: fix stp update API to work with layered netdevices

[Florian Fainelli]

On 16/03/15 10:32, 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.
> 
> v3 to v4:
> 	- fix ret initialization

The changelog should be after "---" otherwise it will get included in
the final git commit, we don't want that as this changelog only makes
sense during the submission process.

> 
> 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..e593b59 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 = -EOPNOTSUPP, 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;
> +
> +	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);
>  
> 


-- 
Florian

Re: [PATCH net-next v4] switchdev: fix stp update API to work with layered netdevices

[Scott Feldman]

On Mon, Mar 16, 2015 at 10:32 AM,  <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.
>
> v3 to v4:
>         - fix ret initialization
>
> 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..e593b59 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 = -EOPNOTSUPP, 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;

I would drop the NETIF_F_HW_SWITCH_OFFLOAD check.  It's not telling
you anything more than the next test for ops->swdev_port_stp_update.

> +
> +       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;

Just return err here, on first failure.  Otherwise you're overwriting
previous err value; doesn't make sense.

> +       }
> +
> +       return ret;
>  }
>  EXPORT_SYMBOL_GPL(netdev_switch_port_stp_update);
>
> --
> 1.7.10.4
>

Re: [PATCH net-next v4] switchdev: fix stp update API to work with layered netdevices

[roopa]

On 3/16/15, 11:10 PM, Scott Feldman wrote:
> On Mon, Mar 16, 2015 at 10:32 AM,  <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.
>>
>> v3 to v4:
>>          - fix ret initialization
>>
>> 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..e593b59 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 = -EOPNOTSUPP, 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;
> I would drop the NETIF_F_HW_SWITCH_OFFLOAD check.  It's not telling
> you anything more than the next test for ops->swdev_port_stp_update.

This was mainly to avoid lowerdev walk where you know that the dev does 
not have the feature.
example: the bond carries this feature flag  if any of its slaves have it.
The lowerdev walk can be stopped at the bond.

I don't mind removing the check, if you prefer that.

thanks,
Roopa

Re: [PATCH net-next v4] switchdev: fix stp update API to work with layered netdevices

[roopa]

On 3/16/15, 2:26 PM, Florian Fainelli wrote:
> On 16/03/15 10:32, 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.
>>
>> v3 to v4:
>> 	- fix ret initialization
> The changelog should be after "---" otherwise it will get included in
> the final git commit, we don't want that as this changelog only makes
> sense during the submission process.
>
ack, thanks..will fix it when i respin the patch.