[PATCH net-next v4 0/3] Add support for sockmap to vsock.

[Bobby Eshleman <bobby.eshleman@bytedance.com>]

We're testing usage of vsock as a way to redirect guest-local UDS
requests to the host and this patch series greatly improves the
performance of such a setup.

Compared to copying packets via userspace, this improves throughput by
121% in basic testing.

Tested as follows.

Setup: guest unix dgram sender -> guest vsock redirector -> host vsock
       server
Threads: 1
Payload: 64k
No sockmap:
- 76.3 MB/s
- The guest vsock redirector was
  "socat VSOCK-CONNECT:2:1234 UNIX-RECV:/path/to/sock"
Using sockmap (this patch):
- 168.8 MB/s (+121%)
- The guest redirector was a simple sockmap echo server,
  redirecting unix ingress to vsock 2:1234 egress.
- Same sender and server programs

*Note: these numbers are from RFC v1

Only the virtio transport has been tested. The loopback transport was
used in writing bpf/selftests, but not thoroughly tested otherwise.

This series requires the skb patch.

Changes in v4:
- af_vsock: fix parameter alignment in vsock_dgram_recvmsg()
- af_vsock: add TCP_ESTABLISHED comment in vsock_dgram_connect()
- vsock/bpf: change ret type to bool

Changes in v3:
- vsock/bpf: Refactor wait logic in vsock_bpf_recvmsg() to avoid
  backwards goto
- vsock/bpf: Check psock before acquiring slock
- vsock/bpf: Return bool instead of int of 0 or 1
- vsock/bpf: Wrap macro args __sk/__psock in parens
- vsock/bpf: Place comment trailer */ on separate line

Changes in v2:
- vsock/bpf: rename vsock_dgram_* -> vsock_*
- vsock/bpf: change sk_psock_{get,put} and {lock,release}_sock() order
  to minimize slock hold time
- vsock/bpf: use "new style" wait
- vsock/bpf: fix bug in wait log
- vsock/bpf: add check that recvmsg sk_type is one dgram, seqpacket, or
  stream.  Return error if not one of the three.
- virtio/vsock: comment __skb_recv_datagram() usage
- virtio/vsock: do not init copied in read_skb()
- vsock/bpf: add ifdef guard around struct proto in dgram_recvmsg()
- selftests/bpf: add vsock loopback config for aarch64
- selftests/bpf: add vsock loopback config for s390x
- selftests/bpf: remove vsock device from vmtest.sh qemu machine
- selftests/bpf: remove CONFIG_VIRTIO_VSOCKETS=y from config.x86_64
- vsock/bpf: move transport-related (e.g., if (!vsk->transport)) checks
  out of fast path

Signed-off-by: Bobby Eshleman <bobby.eshleman@bytedance.com>
---
Bobby Eshleman (3):
      vsock: support sockmap
      selftests/bpf: add vsock to vmtest.sh
      selftests/bpf: add a test case for vsock sockmap

 drivers/vhost/vsock.c                              |   1 +
 include/linux/virtio_vsock.h                       |   1 +
 include/net/af_vsock.h                             |  17 ++
 net/vmw_vsock/Makefile                             |   1 +
 net/vmw_vsock/af_vsock.c                           |  64 +++++++-
 net/vmw_vsock/virtio_transport.c                   |   2 +
 net/vmw_vsock/virtio_transport_common.c            |  25 +++
 net/vmw_vsock/vsock_bpf.c                          | 174 +++++++++++++++++++++
 net/vmw_vsock/vsock_loopback.c                     |   2 +
 tools/testing/selftests/bpf/config.aarch64         |   2 +
 tools/testing/selftests/bpf/config.s390x           |   3 +
 tools/testing/selftests/bpf/config.x86_64          |   3 +
 .../selftests/bpf/prog_tests/sockmap_listen.c      | 163 +++++++++++++++++++
 13 files changed, 452 insertions(+), 6 deletions(-)
---
base-commit: e5b42483ccce50d5b957f474fd332afd4ef0c27b
change-id: 20230327-vsock-sockmap-30b090c70cd1

Best regards,
-- 
Bobby Eshleman <bobby.eshleman@bytedance.com>