Re: [dpdk-dev] [PATCH] kni: implement header_ops parse method

[Igor Ryzhov <iryzhov@nfware.com>]

Hi Ferruh,

What about this patch?
Can you merge it as-is, or should I change it to use relevant
eth_header_ops functions? Or maybe completely use eth_header_ops?

Best regards,
Igor

On Fri, Nov 30, 2018 at 10:07 PM Igor Ryzhov <iryzhov@nfware.com> wrote:

> Hi Ferruh,
>
> header_ops.parse method is used by raw-sockets to fill sockaddr_ll
> structure.
> It is used, for example, in isisd for frrouting.
>
> Regarding your question about eth_header_ops – I, unfortunately, don't
> know why .cache and .cache_update are disabled for KNI.
> I also think that it will be better to use default eth_header_ops.
>
> Best regards,
> Igor
>
> On Tue, Oct 2, 2018 at 7:58 PM Ferruh Yigit <ferruh.yigit@intel.com>
> wrote:
>
>> On 9/27/2018 1:02 AM, Igor Ryzhov wrote:
>> > Signed-off-by: Igor Ryzhov <iryzhov@nfware.com>
>>
>> Hi Igor,
>>
>> What is the motivation to add this support? What is enabled by this?
>>
>>
>> Meanwhile, why we are not using eth_header_ops, which is already set by
>> ether_setup().
>> To disable .cache & .cache_update?
>>
>> If so why not using relevant eth_header_ops (eth_header, eth_header_parse
>> ..)
>> instead of implementing ours?
>>
>> > ---
>> >  kernel/linux/kni/kni_net.c | 14 ++++++++++++++
>> >  1 file changed, 14 insertions(+)
>> >
>> > diff --git a/kernel/linux/kni/kni_net.c b/kernel/linux/kni/kni_net.c
>> > index 7fcfa106c..128a5477c 100644
>> > --- a/kernel/linux/kni/kni_net.c
>> > +++ b/kernel/linux/kni/kni_net.c
>> > @@ -678,6 +678,19 @@ kni_net_header(struct sk_buff *skb, struct
>> net_device *dev,
>> >       return dev->hard_header_len;
>> >  }
>> >
>> > +/*
>> > + *  Extract hardware address from packet
>> > + */
>> > +static int
>> > +kni_net_header_parse(const struct sk_buff *skb, unsigned char *haddr)
>> > +{
>> > +     const struct ethhdr *eth = eth_hdr(skb);
>> > +
>> > +     memcpy(haddr, eth->h_source, ETH_ALEN);
>> > +
>> > +     return ETH_ALEN;
>> > +}
>> > +
>> >  /*
>> >   * Re-fill the eth header
>> >   */
>> > @@ -739,6 +752,7 @@ kni_net_change_carrier(struct net_device *dev, bool
>> new_carrier)
>> >
>> >  static const struct header_ops kni_net_header_ops = {
>> >       .create  = kni_net_header,
>> > +     .parse   = kni_net_header_parse,
>> >  #ifdef HAVE_REBUILD_HEADER
>> >       .rebuild = kni_net_rebuild_header,
>> >  #endif /* < 4.1.0  */
>> >
>>
>>