Subject: Re: [PATCH v3 bpf-next 13/22] xsk: report zero-copy multi-buffer capability via xdp_features

From: Jakub Kicinski <[email-masked]>
Date: Mon, 5 Jun 2023 14:43:10 -0700

On Mon,  5 Jun 2023 16:44:24 +0200 Maciej Fijalkowski wrote:
> diff --git a/include/uapi/linux/netdev.h b/include/uapi/linux/netdev.h
> index 639524b59930..c293014a4197 100644
> --- a/include/uapi/linux/netdev.h
> +++ b/include/uapi/linux/netdev.h
> @@ -24,6 +24,8 @@
>   *   XDP buffer support in the driver napi callback.
>   * @NETDEV_XDP_ACT_NDO_XMIT_SG: This feature informs if netdev implements
>   *   non-linear XDP buffer support in ndo_xdp_xmit callback.
> + * @NETDEV_XDP_ACT_ZC_SG: This feature informs if netdev implements
> + *   non-linear XDP buffer support in AF_XDP zero copy mode.
>   */
>  enum netdev_xdp_act {
>  	NETDEV_XDP_ACT_BASIC = 1,
> @@ -33,8 +35,8 @@ enum netdev_xdp_act {
>  	NETDEV_XDP_ACT_HW_OFFLOAD = 16,
>  	NETDEV_XDP_ACT_RX_SG = 32,
>  	NETDEV_XDP_ACT_NDO_XMIT_SG = 64,
> -
> -	NETDEV_XDP_ACT_MASK = 127,
> +	NETDEV_XDP_ACT_ZC_SG = 128,
> +	NETDEV_XDP_ACT_MASK = 255,

This is auto-generated, you need to make a change to 
  Documentation/netlink/specs/netdev.yaml
then run ./tools/net/ynl/ynl-regen.sh to regenerate the code
(you may need to install python-yaml or some such package).