[v2,00/44] net/virtio: Virtio PMD rework

  Thanks Chenbo, David & Adrian for your review contribution to
the V1. This V2 should implement all the changes you requested,
and fix a few regressions caught while testing.

This series significantly rework Virtio PMD to improve
the Virtio-user PMD and its backends integration.

First part of the series removes the dependency of
Virtio-user ethdev on Virtio PCI, by creating generic
files, adding per-bus meta data, ...

Main (if not single) functionnal change of this first
part is to remove the hack for Virtio-user to work in
IOVA as PA mode, this hack being very fragile.

Second part of the series reworks Virtio-user internal,
by reworking the requests handling so that vDPA and Kernel
backends no more hack into being Vhost-user backend. It
implies implementing new ops for all the request types.
Also, all the backend specific actions are moved from the
virtio_user_dev.c and virtio_user_ethdev.c to their
backend files.

Only functionnal change in this second part is making the
Vhost-user server mode blocking at init time, as long as
a client is not connected. The goal of this change is to
make the Vhost-user support much more robust, as without
blocking, the driver has to assume features that are going
to be supported by the client, which is very fragile and
error prone. As a side-effect, it also simplifies the
logic nin several place of the virtio-user PMD.

Main changes in v2:
===================
- Introduce vdev driver flag for drivers to require IOVA VA mode
- Rebase on top of -rc1 changes
- Fix regressions introduced in V1 (vhost-kernel broken, vhost-user reconnect...)
- Various minor issues & typos fixed
- Fix status feature issue introduced in v20.11, only reproduceable now that server
  mode is made blocking
- Improve failure handling in Virtio-user
- Improve logging

Testing coverage (All passed)
=============================
- Virtio-pci PMD
 * Virtio PMD in guest with Vhost-user backend in host
 * Virtio PMD in guest with Vhost-kernel backend in host
- Virtio-user PMD with Vhost-user backend
 * Vhost-user PMD server <-> Virtio-user client PMD IO loopback
 * Vhost-user PMD client <-> Virtio-user server PMD IO loopback
 * Vhost-user PMD client <-> Virtio-user server PMD reconnect
- Virtio-user PMD with Vhost-kernel backend
 * iperf test case
 * Txonly testpmd
- Virtio-user PMD with Vhost-vDPA backend
 * vdpa-sim (IO loopback)
 * CX-6 DX Kernel vDPA (Tx only)

Maxime Coquelin (44):
  bus/vdev: add helper to get vdev from eth dev
  bus/vdev: add driver IOVA VA mode requirement
  net/virtio: fix getting old status on reconnect
  net/virtio: introduce Virtio bus type
  net/virtio: refactor virtio-user device
  net/virtio: introduce PCI device metadata
  net/virtio: move PCI device init in dedicated file
  net/virtio: move PCI specific dev init to PCI ethdev init
  net/virtio: move MSIX detection to PCI ethdev
  net/virtio: force IOVA as VA mode for Virtio-user
  net/virtio: store PCI type in Virtio device metadata
  net/virtio: add callback for device closing
  net/virtio: validate features at bus level
  net/virtio: remove bus type enum
  net/virtio: move PCI-specific fields to PCI device
  net/virtio: pack virtio HW struct
  net/virtio: move legacy IO to Virtio PCI
  net/virtio: introduce generic virtio header
  net/virtio: move features definition to generic header
  net/virtio: move virtqueue defines in generic header
  net/virtio: move config definitions to generic header
  net/virtio: make interrupt handling more generic
  net/virtio: move vring alignment to generic header
  net/virtio: remove last PCI refs in non-PCI code
  net/virtio: make Vhost-user req sender consistent
  net/virtio: add Virtio-user ops to set owner
  net/virtio: add Virtio-user features ops
  net/virtio: add Virtio-user protocol features ops
  net/virtio: add Virtio-user memory tables ops
  net/virtio: add Virtio-user vring setting ops
  net/virtio: add Virtio-user vring file ops
  net/virtio: add Virtio-user vring address ops
  net/virtio: add Virtio-user status ops
  net/virtio: remove useless request ops
  net/virtio: improve Virtio-user errors handling
  net/virtio: move Vhost-user reqs to Vhost-user backend
  net/virtio: make server mode blocking
  net/virtio: move protocol features to Vhost-user
  net/virtio: introduce backend data
  net/virtio: move Vhost-user specifics to its backend
  net/virtio: move Vhost-kernel data to its backend
  net/virtio: move Vhost-vDPA data to its backend
  net/virtio: improve Vhost-user error logging
  net/virtio: handle Virtio-user setup failure properly

 drivers/bus/vdev/rte_bus_vdev.h               |   6 +
 drivers/bus/vdev/vdev.c                       |  31 +
 drivers/net/virtio/meson.build                |   6 +-
 drivers/net/virtio/virtio.c                   |  71 ++
 drivers/net/virtio/virtio.h                   | 246 +++++
 drivers/net/virtio/virtio_ethdev.c            | 457 +++------
 drivers/net/virtio/virtio_ethdev.h            |   6 +-
 drivers/net/virtio/virtio_pci.c               | 449 +++++----
 drivers/net/virtio/virtio_pci.h               | 286 +-----
 drivers/net/virtio/virtio_pci_ethdev.c        | 226 +++++
 drivers/net/virtio/virtio_ring.h              |   2 +-
 drivers/net/virtio/virtio_rxtx.c              |  90 +-
 drivers/net/virtio/virtio_rxtx_packed.h       |  10 +-
 drivers/net/virtio/virtio_rxtx_packed_avx.h   |  10 +-
 drivers/net/virtio/virtio_rxtx_packed_neon.h  |  10 +-
 drivers/net/virtio/virtio_rxtx_simple.h       |   3 +-
 drivers/net/virtio/virtio_user/vhost.h        |  79 +-
 drivers/net/virtio/virtio_user/vhost_kernel.c | 461 ++++++---
 .../net/virtio/virtio_user/vhost_kernel_tap.c |  25 +-
 .../net/virtio/virtio_user/vhost_kernel_tap.h |   1 +
 drivers/net/virtio/virtio_user/vhost_user.c   | 896 ++++++++++++++----
 drivers/net/virtio/virtio_user/vhost_vdpa.c   | 323 +++++--
 .../net/virtio/virtio_user/virtio_user_dev.c  | 514 +++++-----
 .../net/virtio/virtio_user/virtio_user_dev.h  |  20 +-
 drivers/net/virtio/virtio_user_ethdev.c       | 301 +-----
 drivers/net/virtio/virtqueue.c                |   6 +-
 drivers/net/virtio/virtqueue.h                |  45 +-
 27 files changed, 2704 insertions(+), 1876 deletions(-)
 create mode 100644 drivers/net/virtio/virtio.c
 create mode 100644 drivers/net/virtio/virtio.h
 create mode 100644 drivers/net/virtio/virtio_pci_ethdev.c