Re: [PATCH v4 3/5] net: use ndo_fix_features for ethtool_ops->set_flags

[David Miller <davem@davemloft.net>]

From: Ben Hutchings <bhutchings@solarflare.com>
Date: Mon, 07 Feb 2011 19:46:12 +0000

> On Thu, 2011-02-03 at 15:21 +0100, Michał Mirosław wrote:
>> Signed-off-by: Michał Mirosław <mirq-linux@rere.qmqm.pl>
>> ---
>>  net/core/ethtool.c |   31 +++++++++++++++++++++++++++++--
>>  1 files changed, 29 insertions(+), 2 deletions(-)
>> 
>> diff --git a/net/core/ethtool.c b/net/core/ethtool.c
>> index 555accf..6e7c6f2 100644
>> --- a/net/core/ethtool.c
>> +++ b/net/core/ethtool.c
>> @@ -240,6 +240,34 @@ static int ethtool_set_features(struct net_device *dev, void __user *useraddr)
>>  	return ret;
>>  }
>>  
>> +static int __ethtool_set_flags(struct net_device *dev, u32 data)
>> +{
>> +	u32 changed;
>> +
>> +	if (data & ~flags_dup_features)
>> +		return -EINVAL;
>> +
>> +	/* legacy set_flags() op */
>> +	if (dev->ethtool_ops->set_flags) {
>> +		if (unlikely(dev->hw_features & flags_dup_features))
>> +			netdev_warn(dev,
>> +				"driver BUG: mixed hw_features and set_flags()\n");
>> +		return dev->ethtool_ops->set_flags(dev, data);
>> +	}
>> +
>> +	/* allow changing only bits set in hw_features */
>> +	changed = (data ^ dev->wanted_features) & flags_dup_features;
>> +	if (changed & ~dev->hw_features)
>> +		return -EOPNOTSUPP;
> [...]
> 
> The error code should only be EOPNOTSUPP if (dev->hw_features &
> flags_dup_features) == 0.  Otherwise it should be EINVAL.

I'll fix this up when I apply his patch, thanks Ben.