Re: [PATCH net-next v3] xdp: Add helpers for head length, headroom, and metadata length

[Jesper Dangaard Brouer <hawk@kernel.org>]

On 07/05/2025 19.02, Zvi Effron wrote:
> On Wed, May 7, 2025 at 9:37 AM Jesper Dangaard Brouer <hawk@kernel.org> wrote:
>>
>>
>>
>> On 07/05/2025 15.29, Willem de Bruijn wrote:
>>> Stanislav Fomichev wrote:
>>>> On 05/06, Jon Kohler wrote:
>>>>> Introduce new XDP helpers:
>>>>> - xdp_headlen: Similar to skb_headlen
>>
>> I really dislike xdp_headlen(). This "headlen" originates from an SKB
>> implementation detail, that I don't think we should carry over into XDP
>> land.
>> We need to come up with something that isn't easily mis-read as the
>> header-length.
> 
> ... snip ...
> 
>>>> + * xdp_headlen - Calculate the length of the data in an XDP buffer
> 
> How about xdp_datalen()?

Yes, I like xdp_datalen() :-)
--Jesper

> On Wed, May 7, 2025 at 9:37 AM Jesper Dangaard Brouer <hawk@kernel.org> wrote:
>>
>>
>>
>> On 07/05/2025 15.29, Willem de Bruijn wrote:
>>> Stanislav Fomichev wrote:
>>>> On 05/06, Jon Kohler wrote:
>>>>> Introduce new XDP helpers:
>>>>> - xdp_headlen: Similar to skb_headlen
>>
>> I really dislike xdp_headlen().  This "headlen" originates from an SKB
>> implementation detail, that I don't think we should carry over into XDP
>> land.
>> We need to come up with something that isn't easily mis-read as the
>> header-length.
>>
>>>>> - xdp_headroom: Similar to skb_headroom
>>>>> - xdp_metadata_len: Similar to skb_metadata_len
>>>>>
>>
>> I like naming of these.
>>
>>>>> Integrate these helpers into tap, tun, and XDP implementation to start.
>>>>>
>>>>> No functional changes introduced.
>>>>>
>>>>> Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
>>>>> Signed-off-by: Jon Kohler <jon@nutanix.com>
>>>>> ---
>>>>> v2->v3: Integrate feedback from Stanislav
>>>>> https://patchwork.kernel.org/project/netdevbpf/patch/20250430201120.1794658-1-jon@nutanix.com/
>>>>
>>>> Acked-by: Stanislav Fomichev <sdf@fomichev.me>
>>>
>>> Reviewed-by: Willem de Bruijn <willemb@google.com>
>>>
>>
>> Nacked-by: Jesper Dangaard Brouer <hawk@kernel.org>
>>
>> pw: cr
>>