Re: [PATCH v4] public/io/netif.h: add a new extra type for XDP

[Denis Kirjanov <kda@xxxxxxxxxxxxxxxxx>]

On 5/18/20, Denis Kirjanov <kda@xxxxxxxxxxxxxxxxx> wrote:
> The patch adds a new extra type to be able to diffirentiate
> between RX responses on xen-netfront side with the adjusted offset
> required for XDP processing.
>
> The offset value from a guest is passed via xenstore.

I'm going to send a new version for Linux with the above changes applied.

>
> Signed-off-by: Denis Kirjanov <denis.kirjanov@xxxxxxxx>
> ---
> v4:
> - updated the commit and documenation
>
> v3:
> - updated the commit message
>
> v2:
> - added documentation
> - fixed padding for netif_extra_info
> ---
> ---
>  xen/include/public/io/netif.h | 18 +++++++++++++++++-
>  1 file changed, 17 insertions(+), 1 deletion(-)
>
> diff --git a/xen/include/public/io/netif.h b/xen/include/public/io/netif.h
> index 9fcf91a..a92bf04 100644
> --- a/xen/include/public/io/netif.h
> +++ b/xen/include/public/io/netif.h
> @@ -161,6 +161,17 @@
>   */
>
>  /*
> + * "xdp-headroom" is used to request that extra space is added
> + * for XDP processing.  The value is measured in bytes and passed by
> + * the frontend to be consistent between both ends.
> + * If the value is greater than zero that means that
> + * an RX response is going to be passed to an XDP program for processing.
> + *
> + * "feature-xdp-headroom" is set to "1" by the netback side like other
> features
> + * so a guest can check if an XDP program can be processed.
> + */
> +
> +/*
>   * Control ring
>   * ============
>   *
> @@ -985,7 +996,8 @@ typedef struct netif_tx_request netif_tx_request_t;
>  #define XEN_NETIF_EXTRA_TYPE_MCAST_ADD (2)  /* u.mcast */
>  #define XEN_NETIF_EXTRA_TYPE_MCAST_DEL (3)  /* u.mcast */
>  #define XEN_NETIF_EXTRA_TYPE_HASH      (4)  /* u.hash */
> -#define XEN_NETIF_EXTRA_TYPE_MAX       (5)
> +#define XEN_NETIF_EXTRA_TYPE_XDP       (5)  /* u.xdp */
> +#define XEN_NETIF_EXTRA_TYPE_MAX       (6)
>
>  /* netif_extra_info_t flags. */
>  #define _XEN_NETIF_EXTRA_FLAG_MORE (0)
> @@ -1018,6 +1030,10 @@ struct netif_extra_info {
>              uint8_t algorithm;
>              uint8_t value[4];
>          } hash;
> +        struct {
> +            uint16_t headroom;
> +            uint16_t pad[2]
> +        } xdp;
>          uint16_t pad[3];
>      } u;
>  };
> --
> 1.8.3.1
>
>