Re: [Bonding-devel] [net-next-2.6 PATCH 2/3] bonding: check return value of nofitier when changing type

[Jiri Pirko <jpirko@redhat.com>]

Thu, Mar 11, 2010 at 08:59:09AM CET, jpirko@redhat.com wrote:
>Wed, Mar 10, 2010 at 11:47:10PM CET, shemminger@linux-foundation.org wrote:
>>On Wed, 10 Mar 2010 21:29:35 +0100
>>Jiri Pirko <jpirko@redhat.com> wrote:
>>
>>> diff --git a/net/core/dev.c b/net/core/dev.c
>>> index bcc490c..5de4a15 100644
>>> --- a/net/core/dev.c
>>> +++ b/net/core/dev.c
>>> @@ -1084,9 +1084,9 @@ void netdev_state_change(struct net_device *dev)
>>>  }
>>>  EXPORT_SYMBOL(netdev_state_change);
>>>  
>>> -void netdev_bonding_change(struct net_device *dev, unsigned long event)
>>> +int netdev_bonding_change(struct net_device *dev, unsigned long event)
>>>  {
>>> -	call_netdevice_notifiers(event, dev);
>>> +	return call_netdevice_notifiers(event, dev);
>>>  }
>>>  EXPORT_SYMBOL(netdev_bonding_change);
>>>  
>>
>>I don't think all this pre-post stuff needed.
>>Since this is general (not just bonding) how about
>
>Well actually I reused NETDEV_BONDING_OLDTYPE. This and NETDEV_BONDING_NEWTYPE
>is used in inetdev_event() and addrconf_notify(). These functions apparently
>need to be notified before and after the change.
>
>>
>>int netdev_change_type(struct net_device *dev, int newtype)
>>{
>>	int ret, oldtype;
>>
>>	if (dev->flags & IFF_UP)
>>		return -EBUSY;
>>
>>	oldtype = dev->type;
>>	dev->type = newtype;

Also, the type change is not only about dev->type. See for example
ether_setup(). This function and it's puprose might be misleading...

>>	ret = call_netdevice_notifier(NETDEV_CHANGETYPE, dev);
>>	ret = notifier_to_errno(ret);
>>	if (ret)
>>	     dev->type = oldtype;
>>
>>	return ret;
>>}
>
>I see you point here, but that would be another notifier event. Do you suggest
>to have 3 of them finally? NETDEV_BONDING_OLDTYPE, NETDEV_BONDING_NEWTYPE and
>NETDEV_CHANGETYPE. Looks a bit redundant to me...
>
>Thanks.
>
>Jirka
>