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

[Jürgen Groß <jgross@xxxxxxxx>]

On 18.05.20 10:24, Denis Kirjanov 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.
>
> For Linux the offset value is going to be passed via xenstore.
Why? I can only see disadvantages by using a different communication
mechanism.

> Signed-off-by: Denis Kirjanov <denis.kirjanov@xxxxxxxx>
> ---
>   xen/include/public/io/netif.h | 7 ++++++-
>   1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/xen/include/public/io/netif.h b/xen/include/public/io/netif.h
> index 9fcf91a..759c88a 100644
> --- a/xen/include/public/io/netif.h
> +++ b/xen/include/public/io/netif.h
> @@ -985,7 +985,8 @@ 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 +1019,10 @@ struct netif_extra_info {
>               uint8_t algorithm;
>               uint8_t value[4];
>           } hash;
> +        struct {
> +            uint16_t headroom;
> +            uint32_t pad;
Please use uint16_t pad[2] in order to avoid padding holes.

Additionally you are missing the addition of the related feature
Xenstore nodes in the comment area further up in the same file.


Juergen