Subject: Re: [PATCH v4 net-next 1/4] bpf: xdp: Allow head adjustment in XDP prog

From: John Fastabend <[email-masked]>
Date: Thu, 8 Dec 2016 09:00:44 -0800

On 16-12-08 08:55 AM, Alexei Starovoitov wrote:
> On Thu, Dec 08, 2016 at 10:02:37AM +0100, Daniel Borkmann wrote:
>> On 12/08/2016 12:53 AM, Martin KaFai Lau wrote:
>>> This patch allows XDP prog to extend/remove the packet
>>> data at the head (like adding or removing header).  It is
>>> done by adding a new XDP helper bpf_xdp_adjust_head().
>>>
>>> It also renames bpf_helper_changes_skb_data() to
>>> bpf_helper_changes_pkt_data() to better reflect
>>> that XDP prog does not work on skb.
>>>
>>> This patch adds one "xdp_adjust_head" bit to bpf_prog for the
>>> XDP-capable driver to check if the XDP prog requires
>>> bpf_xdp_adjust_head() support.  The driver can then decide
>>> to error out during XDP_SETUP_PROG.
>>>
>>> Signed-off-by: Martin KaFai Lau <[email-masked]>
>>
>> Acked-by: Daniel Borkmann <[email-masked]>
> 
> Acked-by: Alexei Starovoitov <[email-masked]>
> 

Thanks for fixing up the xdp_buff struct. And for good measure,

Acked-by: John Fastabend <[email-masked]>