Re: Updated zerocopy patch up on kernel.org

[Ingo Molnar <mingo@xxxxxxx>]

On Tue, 9 Jan 2001, David S. Miller wrote:

>    Is there any value to supporting fragments in a driver which
>    doesn't do hardware checksumming?  IIRC Alexey had a patch to do
>    such for Tulip, but I don't see it in the above patchset.
>
> I'm actually considering making the SG w/o hwcsum situation illegal.

i believe it might still make some limited sense for normal sendmsg()
and higher MTUs (or 8k NFS) - we could copy & checksum stuff into the
->tcp_page if SG is possible and thus the SG capability improves the VM.
(because we can allocate at PAGE_SIZE granularity.)

        Ingo