On Mon, Feb 17, 2020 at 1:41 PM Heiner Kallweit <hkallweit1@xxxxxxxxx> wrote:
>
> Several network drivers for chips that support TSO6 share the same code
> for preparing the TCP header. A difference is that some reset the
> payload_len whilst others don't do this. Let's factor out this common
> code to a new helper.
>
> Signed-off-by: Heiner Kallweit <hkallweit1@xxxxxxxxx>
> ---
> include/net/ip6_checksum.h | 12 ++++++++++++
> 1 file changed, 12 insertions(+)
>
> diff --git a/include/net/ip6_checksum.h b/include/net/ip6_checksum.h
> index 7bec95df4..ef0130023 100644
> --- a/include/net/ip6_checksum.h
> +++ b/include/net/ip6_checksum.h
> @@ -76,6 +76,18 @@ static inline void __tcp_v6_send_check(struct sk_buff *skb,
> }
> }
>
> +static inline void tcp_v6_gso_csum_prep(struct sk_buff *skb,
> + bool clear_payload_len)
> +{
> + struct ipv6hdr *ipv6h = ipv6_hdr(skb);
> + struct tcphdr *th = tcp_hdr(skb);
> +
> + if (clear_payload_len)
> + ipv6h->payload_len = 0;
> +
> + th->check = ~tcp_v6_check(0, &ipv6h->saddr, &ipv6h->daddr, 0);
> +}
> +
> #if IS_ENABLED(CONFIG_IPV6)
> static inline void tcp_v6_send_check(struct sock *sk, struct sk_buff *skb)
> {
So functionally I believe this is correct. The only piece I have a
question about is if we should just force the clear_payload_len as
always being the case since the value should either be
ignored/overwritten in any GSO case anyway.
Reviewed-by: Alexander Duyck <alexander.h.duyck@xxxxxxxxxxxxxxx>
