On Wed, Jan 12, 2022 at 05:36:01PM +0100, Mark Kettenis wrote:
> > Date: Wed, 12 Jan 2022 17:02:03 +0100
> > From: Jan Klemkow <[email protected]>
> >
> > Hi,
> >
> > This diff enables TCP and UDP checksum offloading in ix(4) for IPv6.
> >
> > IPv6 extension headers aren't a problem in this case.
> > in6_proto_cksum_out() in netinet6/ip6_output.c disables checksum
> > offloading if ip6_nxt is not TCP or UDP. Thus, we can just use this
> > field.
> >
> > Tested with:
> > ix0 at pci5 dev 0 function 0 "Intel 82599" rev 0x01, msix, 8 queues,
> > address 00:1b:21:94:4c:48
> >
> > OK?
>
> Isn't this the same disaster as the ixl(4) diff you sent earlier? We
> have sparc64 machines with onboard ix(4)...
No, it is another case. The disaster was with TCP bit fields, here
we are talking about IPv6 header.
- A few lines above ip->ip_p is used the same way, and that works.
- I have checked sparc64 assembler, it uses byte instruction.
1bd0: c4 08 60 06 ldub [ %g1 + 6 ], %g2
- struct ip6_hdr uses __packed. I think this is wrong, but that
is a different story.
- Even if I remove this __packed, gcc uses a byte instruction for
reading ip6_nxt.
- m_getptr() returns the correct mbuf and offset to the header. I
think we can assume that a single IPv6 header, that our stack has
created, is in contiguous memory. The IPv4 case just above makes
the same assumption.
OK bluhm@
> > Index: dev/pci/if_ix.c
> > ===================================================================
> > RCS file: /mount/openbsd/cvs/src/sys/dev/pci/if_ix.c,v
> > retrieving revision 1.180
> > diff -u -p -r1.180 if_ix.c
> > --- dev/pci/if_ix.c 27 Jul 2021 01:44:55 -0000 1.180
> > +++ dev/pci/if_ix.c 12 Jan 2022 14:53:14 -0000
> > @@ -1879,7 +1879,8 @@ ixgbe_setup_interface(struct ix_softc *s
> > ifp->if_capabilities |= IFCAP_VLAN_HWTAGGING;
> > #endif
> >
> > - ifp->if_capabilities |= IFCAP_CSUM_TCPv4 | IFCAP_CSUM_UDPv4;
> > + ifp->if_capabilities |= IFCAP_CSUM_TCPv4 | IFCAP_CSUM_UDPv4
> > + | IFCAP_CSUM_TCPv6 | IFCAP_CSUM_UDPv6;
> >
> > /*
> > * Specify the media types supported by this sc and register
> > @@ -2438,9 +2439,7 @@ ixgbe_tx_ctx_setup(struct tx_ring *txr,
> > struct ether_header *eh;
> > #endif
> > struct ip *ip;
> > -#ifdef notyet
> > struct ip6_hdr *ip6;
> > -#endif
> > struct mbuf *m;
> > int ipoff;
> > uint32_t vlan_macip_lens = 0, type_tucmd_mlhl = 0;
> > @@ -2521,19 +2520,16 @@ ixgbe_tx_ctx_setup(struct tx_ring *txr,
> > ipproto = ip->ip_p;
> > type_tucmd_mlhl |= IXGBE_ADVTXD_TUCMD_IPV4;
> > break;
> > -#ifdef notyet
> > case ETHERTYPE_IPV6:
> > if (mp->m_pkthdr.len < ehdrlen + sizeof(*ip6))
> > return (-1);
> > m = m_getptr(mp, ehdrlen, &ipoff);
> > KASSERT(m != NULL && m->m_len - ipoff >= sizeof(*ip6));
> > - ip6 = (struct ip6 *)(m->m_data + ipoff);
> > + ip6 = (struct ip6_hdr *)(m->m_data + ipoff);
> > ip_hlen = sizeof(*ip6);
> > - /* XXX-BZ this will go badly in case of ext hdrs. */
> > ipproto = ip6->ip6_nxt;
> > type_tucmd_mlhl |= IXGBE_ADVTXD_TUCMD_IPV6;
> > break;
> > -#endif
> > default:
> > offload = FALSE;
> > break;
> > Index: dev/pci/ixgbe.h
> > ===================================================================
> > RCS file: /mount/openbsd/cvs/src/sys/dev/pci/ixgbe.h,v
> > retrieving revision 1.32
> > diff -u -p -r1.32 ixgbe.h
> > --- dev/pci/ixgbe.h 18 Jul 2020 07:18:22 -0000 1.32
> > +++ dev/pci/ixgbe.h 12 Jan 2022 14:57:13 -0000
> > @@ -65,6 +65,7 @@
> > #include <netinet/in.h>
> > #include <netinet/if_ether.h>
> > #include <netinet/ip.h>
> > +#include <netinet/ip6.h>
> >
> > #if NBPFILTER > 0
> > #include <net/bpf.h>
> >
> >
