Re: [RFC net-next] udp: add a GSO type for UDPv6

[tanhuazhong]

On 2020/9/2 22:33, Willem de Bruijn wrote:
> On Wed, Sep 2, 2020 at 2:18 PM Huazhong Tan <tanhuazhong@xxxxxxxxxx> wrote:
> > In some cases, for UDP GSO, UDPv4 and UDPv6 need to be handled
> > separately, for example, checksum offload, so add new GSO type
> > SKB_GSO_UDPV6_L4 for UDPv6, and the old SKB_GSO_UDP_L4 stands
> > for UDPv4.
>
> This is in preparation for hardware you have that actually cares about
> this distinction, I guess?

it is mainly for separating checksum offload of IPv4 and IPv6 right now.
with this patch, the user can switch checksum offload of IPv4 and not
affect IPv6's, vice versa.

> > diff --git a/include/linux/netdev_features.h b/include/linux/netdev_features.h
> > index 2cc3cf8..b7c1a76 100644
> > --- a/include/linux/netdev_features.h
> > +++ b/include/linux/netdev_features.h
> > @@ -54,6 +54,7 @@ enum {
> >          NETIF_F_GSO_UDP_BIT,            /* ... UFO, deprecated except tuntap */
> >          NETIF_F_GSO_UDP_L4_BIT,         /* ... UDP payload GSO (not UFO) */
> >          NETIF_F_GSO_FRAGLIST_BIT,               /* ... Fraglist GSO */
> > +       NETIF_F_GSO_UDPV6_L4_BIT,       /* ... UDPv6 payload GSO (not UFO) */
> >          /**/NETIF_F_GSO_LAST =          /* last bit, see GSO_MASK */
> >                  NETIF_F_GSO_FRAGLIST_BIT,
>
> Need to update NETIF_F_GSO_LAST then, too.

ok, thanks.

>