[PATCH 00/16] Support VIRTIO_F_RING_RESET for virtio-net and vhost-user in virtio pci

[Kangjie Xu <kangjie.xu@linux.alibaba.com>]

The virtio queue reset function has already been defined in the virtio spec 1.2.
The relevant virtio spec information is here:

    https://github.com/oasis-tcs/virtio-spec/issues/124
    https://github.com/oasis-tcs/virtio-spec/issues/139

This patch set is to support this function in QEMU. It consists of two parts: virtio-net
and vhost-user. The patches 1-7 are the implementation for virtio-net and the patches
8-16 are for vhost-user. 

The process of virt queue reset can be concluded as:
1. The virtqueue is disabled when VIRTIO_PCI_COMMON_Q_RESET is written.
2. Then the virtqueue is restarted after the information of vrings is passed to QEMU and
VIRTIO_PCI_COMMON_Q_ENABLE is written.

Test environment:
    Host: 5.4.189
    Qemu: QEMU emulator version 7.0.50
    Guest: 5.19.0-rc3 (With vq reset support)
    DPDK: 22.07-rc1 (With vq reset support)
    Test Cmd: ethtool -g eth1; ethtool -G eth1 rx $1 tx $2; ethtool -g eth1;

    The frontend can resize the virtio queue, then virtio queue reset function should
    be triggered.

    The default is split mode, modify Qemu virtio-net to add PACKED feature to 
    test packed mode.

Guest Kernel Patch:
    https://lore.kernel.org/bpf/20220629065656.54420-1-xuanzhuo@linux.alibaba.com/

DPDK Code:
    https://github.com/middaywords/dpdk/commit/098c8e1dfae10b747da8dd8950a82890efca7bee

Please review. Thanks.

Kangjie Xu (9):
  vhost: add op to enable or disable a single vring
  vhost-user: enable/disable a single vring
  vhost: extract the logic of unmapping the vrings and desc
  vhost: introduce restart and release for vhost_dev's vqs
  vhost-net: introduce restart and stop for vhost_net's vqs
  virtio: introduce queue_enable in virtio
  virtio-net: support queue_enable for vhost-user
  virtio-net: support queue_reset for vhost-user
  vhost-net: vq reset feature bit support

Xuan Zhuo (7):
  virtio-pci: virtio_pci_common_cfg add queue_notify_data
  virtio: add VIRTIO_F_RING_RESET
  virtio: pci: virtio_pci_common_cfg add queue_reset
  virtio: introduce __virtio_queue_reset()
  virtio: introduce virtio_queue_reset()
  virtio-pci: support queue reset
  virtio-net: support queue reset

 hw/net/vhost_net.c                            | 56 ++++++++++++++++++
 hw/net/virtio-net.c                           | 40 +++++++++++++
 hw/virtio/vhost-user.c                        | 55 +++++++++++++++---
 hw/virtio/vhost.c                             | 49 ++++++++++++++--
 hw/virtio/virtio-pci.c                        | 17 ++++++
 hw/virtio/virtio.c                            | 57 +++++++++++++------
 include/hw/virtio/vhost-backend.h             |  4 ++
 include/hw/virtio/vhost.h                     |  6 ++
 include/hw/virtio/virtio-pci.h                |  1 +
 include/hw/virtio/virtio.h                    |  4 ++
 include/net/vhost_net.h                       |  5 ++
 .../standard-headers/linux/virtio_config.h    |  5 ++
 include/standard-headers/linux/virtio_pci.h   |  4 ++
 13 files changed, 274 insertions(+), 29 deletions(-)

-- 
2.32.0