[PATCH v3 0/6] TUN/VirtioNet USO features support.

[Andrew Melnychenko <andrew@daynix.com>]

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. 

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.

 drivers/net/tap.c               | 10 ++++++++--
 drivers/net/tun.c               |  8 +++++++-
 drivers/net/virtio_net.c        | 19 +++++++++++++++----
 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          |  2 +-
 7 files changed, 47 insertions(+), 8 deletions(-)

-- 
2.37.2