passt, branch vhost-user

tcp: Move tcp_l2_buf_fill_headers() to tcp_buf.c

2024-11-15T09:55:53+00:00

This function only has callers in tcp_buf.c.  More importantly, it's
inherently tied to the "buf" path, because it uses internal knowledge of
how we lay out the various headers across our locally allocated buffers.

Therefore, move it to tcp_buf.c.

Slightly reformat the prototypes while we're at it.

Signed-off-by: David Gibson 
Signed-off-by: Laurent Vivier

tcp_vu: Share more header construction between IPv4 and IPv6 paths

2024-11-15T09:55:53+00:00

tcp_vu_send_flag() and tcp_vu_prepare() both needs to do some different
things for IPv4 vs. IPv6.  However the two paths have a number of lines of
duplicated code.  We can share those at the expense of an additional
conditional (which we might be able to simplify again later).

Signed-off-by: David Gibson 
Signed-off-by: Laurent Vivier

test: Add tests for passt in vhost-user mode

2024-11-15T09:55:53+00:00

Run functional and performance tests for vhost-user mode as well. For
functional tests, we add passt_vu and passt_vu_in_ns as symbolic links
to their non-vhost-user counterparts, as no differences are intended
but we want to distinguish them in test logs.

For performance tests, instead, we add separate perf/passt_vu_tcp and
perf/passt_vu_udp files, as we need longer test duration, as well as
higher UDP sending bandwidths and larger TCP windows, to actually get
the highest throughput vhost-user mode offers.

For valgrind tests, vhost-user mode needs two extra system calls:
statx and readlink. Add them as EXTRA_SYSCALLS for the valgrind
target.

Signed-off-by: Laurent Vivier 
Reviewed-by: David Gibson 
Signed-off-by: Stefano Brivio

vhost-user: add vhost-user

2024-11-15T09:55:53+00:00

add virtio and vhost-user functions to connect with QEMU.

  $ ./passt --vhost-user

and

  # qemu-system-x86_64 ... -m 4G \
        -object memory-backend-memfd,id=memfd0,share=on,size=4G \
        -numa node,memdev=memfd0 \
        -chardev socket,id=chr0,path=/tmp/passt_1.socket \
        -netdev vhost-user,id=netdev0,chardev=chr0 \
        -device virtio-net,mac=9a:2b:2c:2d:2e:2f,netdev=netdev0 \
        ...

Signed-off-by: Laurent Vivier

passt: rename tap_sock_init() to tap_backend_init()

2024-11-15T09:54:01+00:00

Extract pool storage initialization loop to tap_sock_update_pool(),
extract QEMU hints to tap_backend_show_hints().

Signed-off-by: Laurent Vivier 
Reviewed-by: David Gibson

tcp: Export headers functions

2024-11-15T09:53:40+00:00

Export tcp_fill_headers[4|6]() and tcp_update_check_tcp[4|6]().

They'll be needed by vhost-user.

Signed-off-by: Laurent Vivier 
Reviewed-by: David Gibson

udp: Prepare udp.c to be shared with vhost-user

2024-11-15T09:53:40+00:00

Export udp_payload_t, udp_update_hdr4(), udp_update_hdr6() and
udp_sock_errs().

Rename udp_listen_sock_handler() to udp_buf_listen_sock_handler() and
udp_reply_sock_handler to udp_buf_reply_sock_handler().

Signed-off-by: Laurent Vivier 
Reviewed-by: David Gibson

vhost-user: introduce vhost-user API

2024-11-15T09:53:40+00:00

Add vhost_user.c and vhost_user.h that define the functions needed
to implement vhost-user backend.

Signed-off-by: Laurent Vivier

vhost-user: introduce virtio API

2024-11-15T09:53:40+00:00

Add virtio.c and virtio.h that define the functions needed
to manage virtqueues.

Signed-off-by: Laurent Vivier

packet: replace struct desc by struct iovec

2024-11-15T09:53:40+00:00

To be able to manage buffers inside a shared memory provided
by a VM via a vhost-user interface, we cannot rely on the fact
that buffers are located in a pre-defined memory area and use
a base address and a 32bit offset to address them.

We need a 64bit address, so replace struct desc by struct iovec
and update range checking.

Signed-off-by: Laurent Vivier 
Reviewed-by: David Gibson