Re: [RFC v2 2/2] e100: Support RXFCS feature flag.

["Michał Mirosław" <mirqus@gmail.com>]

W dniu 29 czerwca 2011 16:35 użytkownik Ben Greear
<greearb@candelatech.com> napisał:
> On 06/29/2011 07:33 AM, Michał Mirosław wrote:
>> W dniu 29 czerwca 2011 16:22 użytkownik Ben Greear
>> <greearb@candelatech.com>  napisał:
>>> On 06/29/2011 04:37 AM, Michał Mirosław wrote:
>>>> 2011/6/24<greearb@candelatech.com>:
>>>>> From: Ben Greear<greearb@candelatech.com>
>>>>>
>>>>> This allows e100 to be configured to append the
>>>>> Ethernet FCS to the skb.
>>>>>
>>>>> Useful for sniffing networks.
>>>>>
>>>>> Signed-off-by: Ben Greear<greearb@candelatech.com>
>>>>> ---
>>>>> :100644 100644 c1352c6... 761f6f5... M  drivers/net/e100.c
>>>>>  drivers/net/e100.c |   15 ++++++++++++---
>>>>>  1 files changed, 12 insertions(+), 3 deletions(-)
>>>>>
>>>>> diff --git a/drivers/net/e100.c b/drivers/net/e100.c
>>>>> index c1352c6..761f6f5 100644
>>>>> --- a/drivers/net/e100.c
>>>>> +++ b/drivers/net/e100.c
>>>>> @@ -1089,6 +1089,7 @@ static void e100_configure(struct nic *nic,
>>>>> struct
>>>>> cb *cb, struct sk_buff *skb)
>>>>>  {
>>>>>        struct config *config =&cb->u.config;
>>>>>        u8 *c = (u8 *)config;
>>>>> +       struct net_device *netdev = nic->netdev;
>>>>>
>>>>>        cb->command = cpu_to_le16(cb_config);
>>>>>
>>>>> @@ -1132,6 +1133,9 @@ static void e100_configure(struct nic *nic,
>>>>> struct
>>>>> cb *cb, struct sk_buff *skb)
>>>>>                config->promiscuous_mode = 0x1;         /* 1=on, 0=off
>>>>> */
>>>>>        }
>>>>>
>>>>> +       if (netdev->wanted_features&    NETIF_F_RXFCS)
>>>>> +               config->rx_crc_transfer = 0x1;  /* 1=save, 0=discard */
>>>>> +
>>>>
>>>> You should check netdev->features here.
>>>
>>> I thought 'features' was what the NIC could support, and wanted_features
>>> was what the NIC was currently configured to support?  I don't want
>>> to rx the CRC all the time, just when users enable it...
>>
>> hw_features is what device could support, and features is what device
>> has currently turned on.
> Ok, thanks for that correction.
> What does wanted_features mean, then?

What user wants to be active. It should be more clear to you if you
read the implemetation: netdev_update_features() and friends.

Best Regards,
Michał Mirosław