Date: Sat, 13 Jun 2009 17:01:36 +0900 From: Pyun YongHyeon <pyunyh@gmail.com> To: Michael Tuexen <tuexen@freebsd.org> Cc: FreeBSD net mailing list <freebsd-net@freebsd.org>, Andrew Gallatin <gallatin@cs.duke.edu> Subject: Re: Ethernet NIC drivers depending unconditionally on INET Message-ID: <20090613080136.GB76872@michelle.cdnetworks.co.kr> In-Reply-To: <EB178368-A869-4190-BDBC-F88F77C56F6A@freebsd.org> References: <20090611184555.J22887@maildrop.int.zabbadoz.net> <20090612013406.GB72855@michelle.cdnetworks.co.kr> <20090612100900.M22887@maildrop.int.zabbadoz.net> <71535CB2-2784-4253-B67E-017FEAD57637@freebsd.org> <4A32F752.90003@cs.duke.edu> <EB178368-A869-4190-BDBC-F88F77C56F6A@freebsd.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Sat, Jun 13, 2009 at 09:15:06AM +0200, Michael Tuexen wrote:
> On Jun 13, 2009, at 2:48 AM, Andrew Gallatin wrote:
>
> >Michael Tuexen wrote:
> >
> >> I'm not sure if we need additional IFCAP_RXCSUM6 IFCAP_TXCSUM6
> >> capabilities... Why would we want to enable IPv4 offloading and
> >> not IPv6 or vice versa?
> >
> >I'd assume that some older hardware supports IPv4 offloads, but
> >might not have support for IPv6 offloads.
> Sure. But then the driver only provides the CSUM_ flags which
> are appropriate. For example, a similar thing is already in the
> igb driver:
>
> 1167 if (ifp->if_capenable & IFCAP_TXCSUM) {
> 1168 ifp->if_hwassist |= (CSUM_TCP | CSUM_UDP);
> 1169 #if __FreeBSD_version >= 800000
> 1170 if (adapter->hw.mac.type == e1000_82576)
> 1171 ifp->if_hwassist |= CSUM_SCTP;
> 1172 #endif
> 1173 }
That would disable all IPv4/IPv6 checksum offloading if
administrator disable IFCAP_TXCSUM. If we have IFCAP_TXCSUM6/
IFCAP_RXCSUM6 users could choose best working one even if some part
of driver/controller had checksum offload bugs.
>
> For FreeBSD 8 and a particular chip, SCTP checksum offloading
> is supported. No need for a special IFCAP_TXCSUM.
>
> Best regards
> Michael
>
> >
> >Drew
>
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20090613080136.GB76872>