Re: [PATCH v7 00/26] virtio pci support VIRTIO_F_RING_RESET

[Jason Wang <jasowang@redhat.com>]

在 2022/3/8 下午8:34, Xuan Zhuo 写道:
> The virtio spec already supports the virtio queue reset function. This patch set
> is to add this function to the kernel. The relevant virtio spec information is
> here:
>
>      https://github.com/oasis-tcs/virtio-spec/issues/124
>
> Also regarding MMIO support for queue reset, I plan to support it after this
> patch is passed.
>
> Performing reset on a queue is divided into four steps:
>       1. virtio_reset_vq()              - notify the device to reset the queue
>       2. virtqueue_detach_unused_buf()  - recycle the buffer submitted
>       3. virtqueue_reset_vring()        - reset the vring (may re-alloc)
>       4. virtio_enable_resetq()         - mmap vring to device, and enable the queue
>
> The first part 1-17 of this patch set implements virtio pci's support and API
> for queue reset. The latter part is to make virtio-net support set_ringparam. Do
> these things for this feature:
>
>        1. virtio-net support rx,tx reset
>        2. find_vqs() support to special the max size of each vq
>        3. virtio-net support set_ringparam
>
> #1 -#3 :       prepare
> #4 -#12:       virtio ring support reset vring of the vq
> #13-#14:       add helper
> #15-#17:       virtio pci support reset queue and re-enable
> #18-#21:       find_vqs() support sizes to special the max size of each vq
> #23-#24:       virtio-net support rx, tx reset
> #22, #25, #26: virtio-net support set ringparam
>
> Test environment:
>      Host: 4.19.91
>      Qemu: QEMU emulator version 6.2.50 (with vq reset support)
>      Test Cmd:  ethtool -G eth1 rx $1 tx $2; ethtool -g eth1
>
>      The default is split mode, modify Qemu virtio-net to add PACKED feature to test
>      packed mode.
>
>
> Please review. Thanks.
>
> v7:
>    1. fix #6 subject typo
>    2. fix #6 ring_size_in_bytes is uninitialized
>    3. check by: make W=12
>
> v6:
>    1. virtio_pci: use synchronize_irq(irq) to sync the irq callbacks
>    2. Introduce virtqueue_reset_vring() to implement the reset of vring during
>       the reset process. May use the old vring if num of the vq not change.
>    3. find_vqs() support sizes to special the max size of each vq
>
> v5:
>    1. add virtio-net support set_ringparam
>
> v4:
>    1. just the code of virtio, without virtio-net
>    2. Performing reset on a queue is divided into these steps:
>      1. reset_vq: reset one vq
>      2. recycle the buffer from vq by virtqueue_detach_unused_buf()
>      3. release the ring of the vq by vring_release_virtqueue()
>      4. enable_reset_vq: re-enable the reset queue
>    3. Simplify the parameters of enable_reset_vq()
>    4. add container structures for virtio_pci_common_cfg
>
> v3:
>    1. keep vq, irq unreleased


The series became kind of huge.

I'd suggest to split it into two series.

1) refactoring of the virtio_ring to prepare for the resize
2) the reset support + virtio-net support

Thanks


>
> *** BLURB HERE ***
>
> Xuan Zhuo (26):
>    virtio_pci: struct virtio_pci_common_cfg add queue_notify_data
>    virtio: queue_reset: add VIRTIO_F_RING_RESET
>    virtio: add helper virtqueue_get_vring_max_size()
>    virtio_ring: split: extract the logic of creating vring
>    virtio_ring: split: extract the logic of init vq and attach vring
>    virtio_ring: packed: extract the logic of creating vring
>    virtio_ring: packed: extract the logic of init vq and attach vring
>    virtio_ring: extract the logic of freeing vring
>    virtio_ring: split: implement virtqueue_reset_vring_split()
>    virtio_ring: packed: implement virtqueue_reset_vring_packed()
>    virtio_ring: introduce virtqueue_reset_vring()
>    virtio_ring: update the document of the virtqueue_detach_unused_buf
>      for queue reset
>    virtio: queue_reset: struct virtio_config_ops add callbacks for
>      queue_reset
>    virtio: add helper for queue reset
>    virtio_pci: queue_reset: update struct virtio_pci_common_cfg and
>      option functions
>    virtio_pci: queue_reset: extract the logic of active vq for modern pci
>    virtio_pci: queue_reset: support VIRTIO_F_RING_RESET
>    virtio: find_vqs() add arg sizes
>    virtio_pci: support the arg sizes of find_vqs()
>    virtio_mmio: support the arg sizes of find_vqs()
>    virtio: add helper virtio_find_vqs_ctx_size()
>    virtio_net: get ringparam by virtqueue_get_vring_max_size()
>    virtio_net: split free_unused_bufs()
>    virtio_net: support rx/tx queue reset
>    virtio_net: set the default max ring size by find_vqs()
>    virtio_net: support set_ringparam
>
>   arch/um/drivers/virtio_uml.c             |   2 +-
>   drivers/net/virtio_net.c                 | 257 ++++++++--
>   drivers/platform/mellanox/mlxbf-tmfifo.c |   3 +-
>   drivers/remoteproc/remoteproc_virtio.c   |   2 +-
>   drivers/s390/virtio/virtio_ccw.c         |   2 +-
>   drivers/virtio/virtio_mmio.c             |  12 +-
>   drivers/virtio/virtio_pci_common.c       |  28 +-
>   drivers/virtio/virtio_pci_common.h       |   3 +-
>   drivers/virtio/virtio_pci_legacy.c       |   8 +-
>   drivers/virtio/virtio_pci_modern.c       | 146 +++++-
>   drivers/virtio/virtio_pci_modern_dev.c   |  36 ++
>   drivers/virtio/virtio_ring.c             | 584 +++++++++++++++++------
>   drivers/virtio/virtio_vdpa.c             |   2 +-
>   include/linux/virtio.h                   |  12 +
>   include/linux/virtio_config.h            |  74 ++-
>   include/linux/virtio_pci_modern.h        |   2 +
>   include/uapi/linux/virtio_config.h       |   7 +-
>   include/uapi/linux/virtio_pci.h          |  14 +
>   18 files changed, 979 insertions(+), 215 deletions(-)
>
> --
> 2.31.0
>