Re: [PATCH v4 0/6] TUN/VirtioNet USO features support.

From: Andrew Melnichenko
Date: Thu Dec 01 2022 - 17:51:52 EST


Sorry, got issues with the internet during sending it. Now, all should be done.

On Fri, Dec 2, 2022 at 12:33 AM Michael S. Tsirkin <mst@xxxxxxxxxx> wrote:
>
> On Thu, Dec 01, 2022 at 11:56:38PM +0200, Andrew Melnychenko wrote:
> > Added new offloads for TUN devices TUN_F_USO4 and TUN_F_USO6.
> > Technically they enable NETIF_F_GSO_UDP_L4
> > (and only if USO4 & USO6 are set simultaneously).
> > It allows the transmission of large UDP packets.
> >
> > UDP Segmentation Offload (USO/GSO_UDP_L4) - ability to split UDP packets
> > into several segments. It's similar to UFO, except it doesn't use IP
> > fragmentation. The drivers may push big packets and the NIC will split
> > them(or assemble them in case of receive), but in the case of VirtioNet
> > we just pass big UDP to the host. So we are freeing the driver from doing
> > the unnecessary job of splitting. The same thing for several guests
> > on one host, we can pass big packets between guests.
> >
> > Different features USO4 and USO6 are required for qemu where Windows
> > guests can enable disable USO receives for IPv4 and IPv6 separately.
> > On the other side, Linux can't really differentiate USO4 and USO6, for now.
> > For now, to enable USO for TUN it requires enabling USO4 and USO6 together.
> > In the future, there would be a mechanism to control UDP_L4 GSO separately.
> >
> > New types for virtio-net already in virtio-net specification:
> > https://github.com/oasis-tcs/virtio-spec/issues/120
> >
> > Test it WIP Qemu https://github.com/daynix/qemu/tree/USOv3
> >
> > Andrew (5):
> > uapi/linux/if_tun.h: Added new offload types for USO4/6.
> > driver/net/tun: Added features for USO.
> > uapi/linux/virtio_net.h: Added USO types.
> > linux/virtio_net.h: Support USO offload in vnet header.
> > drivers/net/virtio_net.c: Added USO support.
> >
> > Andrew Melnychenko (1):
> > udp: allow header check for dodgy GSO_UDP_L4 packets.
>
> I don't see patches except 0 on list.
>
> > drivers/net/tap.c | 10 ++++++++--
> > drivers/net/tun.c | 8 +++++++-
> > drivers/net/virtio_net.c | 24 +++++++++++++++++++++---
> > include/linux/virtio_net.h | 9 +++++++++
> > include/uapi/linux/if_tun.h | 2 ++
> > include/uapi/linux/virtio_net.h | 5 +++++
> > net/ipv4/udp_offload.c | 3 ++-
> > net/ipv6/udp_offload.c | 3 ++-
> > 8 files changed, 56 insertions(+), 8 deletions(-)
> >
> > --
> > 2.38.1
> >
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> >
>