On Sun, May 6, 2018 at 2:50 PM, Willem de Bruijn <willemdebruijn.ker...@gmail.com> wrote: > On Sat, May 5, 2018 at 3:31 AM, Alexander Duyck > <alexander.du...@gmail.com> wrote: >> From: Alexander Duyck <alexander.h.du...@intel.com> >> >> This patch adds support for a software provided checksum and GSO_PARTIAL >> segmentation support. With this we can offload UDP segmentation on devices >> that only have partial support for tunnels. >> >> Since we are no longer needing the hardware checksum we can drop the checks >> in the segmentation code that were verifying if it was present. >> >> Signed-off-by: Alexander Duyck <alexander.h.du...@intel.com> >> --- >> net/ipv4/udp_offload.c | 28 ++++++++++++++++++---------- >> net/ipv6/udp_offload.c | 11 +---------- >> 2 files changed, 19 insertions(+), 20 deletions(-) >> >> diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c >> index 946d06d2aa0c..fd94bbb369b2 100644 >> --- a/net/ipv4/udp_offload.c >> +++ b/net/ipv4/udp_offload.c >> @@ -217,6 +217,13 @@ struct sk_buff *__udp_gso_segment(struct sk_buff >> *gso_skb, >> return segs; >> } >> >> + /* GSO partial and frag_list segmentation only requires splitting >> + * the frame into an MSS multiple and possibly a remainder, both >> + * cases return a GSO skb. So update the mss now. >> + */ >> + if (skb_is_gso(segs)) >> + mss *= skb_shinfo(segs)->gso_segs; >> + >> seg = segs; >> uh = udp_hdr(seg); >> >> @@ -237,6 +244,11 @@ struct sk_buff *__udp_gso_segment(struct sk_buff >> *gso_skb, >> uh->len = newlen; >> uh->check = check; >> >> + if (seg->ip_summed == CHECKSUM_PARTIAL) >> + gso_reset_checksum(seg, ~check); >> + else >> + uh->check = gso_make_checksum(seg, ~check); > > Here and below, this needs > > if (uh->check == 0) > uh->check = CSUM_MANGLED_0; > > similar to __skb_udp_tunnel_segment?
Good call, though I think I might change this up a bit and do something like: uh->check = gso_make_checksum(seg, ~check) ? : CSUM_MANGLED_0; That way I can avoid the extra read. Thanks. - Alex
