Re: [PATCH v8 bpf-next 08/14] bpf: add multi-buff support to the bpf_xdp_adjust_tail() API

On Thu, Apr 08, 2021 at 10:15:47PM +0300, Vladimir Oltean wrote:

quoted

+		if (unlikely(offset > ((int)(xdp->data_end - xdp->data) +
+				       xdp_sinfo->data_length -
+				       ETH_HLEN)))

Also: should we have some sort of helper for calculating the total
length of an xdp_frame (head + frags)? Maybe it's just me, but I find it
slightly confusing that xdp_sinfo->data_length does not account for
everything.

I see now that xdp_buff :: frame_length is added in patch 10. It is a
bit strange to not use it wherever you can? Could patch 10 be moved
before patch 8?