Re: [PATCH v2 1/3] qapi/vfio: Add VFIO migration QAPI event

["Cédric Le Goater" <clg@redhat.com>]

On 5/9/24 11:09, Avihai Horon wrote:
> Add a new QAPI event for VFIO migration. This event will be emitted when
> a VFIO device changes its migration state, for example, during migration
> or when stopping/starting the guest.
> 
> This event can be used by management applications to get updates on the
> current state of the VFIO device for their own purposes.
> 
> Note that this new event is introduced since VFIO devices have a unique
> set of migration states which cannot be described as accurately by other
> existing events such as run state or migration status.
> 
> Signed-off-by: Avihai Horon <avihaih@nvidia.com>

LGTM,

Reviewed-by: Cédric Le Goater <clg@redhat.com>

Thanks,

C.


> ---
>   MAINTAINERS           |  1 +
>   qapi/qapi-schema.json |  1 +
>   qapi/vfio.json        | 67 +++++++++++++++++++++++++++++++++++++++++++
>   qapi/meson.build      |  1 +
>   4 files changed, 70 insertions(+)
>   create mode 100644 qapi/vfio.json
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 84391777db..b5f1de459e 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -2160,6 +2160,7 @@ F: hw/vfio/*
>   F: include/hw/vfio/
>   F: docs/igd-assign.txt
>   F: docs/devel/migration/vfio.rst
> +F: qapi/vfio.json
>   
>   vfio-ccw
>   M: Eric Farman <farman@linux.ibm.com>
> diff --git a/qapi/qapi-schema.json b/qapi/qapi-schema.json
> index 5e33da7228..b1581988e4 100644
> --- a/qapi/qapi-schema.json
> +++ b/qapi/qapi-schema.json
> @@ -78,5 +78,6 @@
>   { 'include': 'pci.json' }
>   { 'include': 'stats.json' }
>   { 'include': 'virtio.json' }
> +{ 'include': 'vfio.json' }
>   { 'include': 'cryptodev.json' }
>   { 'include': 'cxl.json' }
> diff --git a/qapi/vfio.json b/qapi/vfio.json
> new file mode 100644
> index 0000000000..a0e5013188
> --- /dev/null
> +++ b/qapi/vfio.json
> @@ -0,0 +1,67 @@
> +# -*- Mode: Python -*-
> +# vim: filetype=python
> +#
> +
> +##
> +# = VFIO devices
> +##
> +
> +##
> +# @VfioMigrationState:
> +#
> +# An enumeration of the VFIO device migration states.
> +#
> +# @stop: The device is stopped.
> +#
> +# @running: The device is running.
> +#
> +# @stop-copy: The device is stopped and its internal state is available
> +#     for reading.
> +#
> +# @resuming: The device is stopped and its internal state is available
> +#     for writing.
> +#
> +# @running-p2p: The device is running in the P2P quiescent state.
> +#
> +# @pre-copy: The device is running, tracking its internal state and its
> +#     internal state is available for reading.
> +#
> +# @pre-copy-p2p: The device is running in the P2P quiescent state,
> +#     tracking its internal state and its internal state is available
> +#     for reading.
> +#
> +# Since: 9.1
> +##
> +{ 'enum': 'VfioMigrationState',
> +  'data': [ 'stop', 'running', 'stop-copy', 'resuming', 'running-p2p',
> +            'pre-copy', 'pre-copy-p2p' ],
> +  'prefix': 'QAPI_VFIO_MIGRATION_STATE' }
> +
> +##
> +# @VFIO_MIGRATION:
> +#
> +# This event is emitted when a VFIO device migration state is changed.
> +#
> +# @device-id: The device's id, if it has one.
> +#
> +# @qom-path: The device's QOM path.
> +#
> +# @device-state: The new changed device migration state.
> +#
> +# Since: 9.1
> +#
> +# Example:
> +#
> +#     <- { "timestamp": { "seconds": 1713771323, "microseconds": 212268 },
> +#          "event": "VFIO_MIGRATION",
> +#          "data": {
> +#              "device-id": "vfio_dev1",
> +#              "qom-path": "/machine/peripheral/vfio_dev1",
> +#              "device-state": "stop" } }
> +##
> +{ 'event': 'VFIO_MIGRATION',
> +  'data': {
> +      'device-id': 'str',
> +      'qom-path': 'str',
> +      'device-state': 'VfioMigrationState'
> +  } }
> diff --git a/qapi/meson.build b/qapi/meson.build
> index c92af6e063..e7bc54e5d0 100644
> --- a/qapi/meson.build
> +++ b/qapi/meson.build
> @@ -52,6 +52,7 @@ qapi_all_modules = [
>     'stats',
>     'trace',
>     'transaction',
> +  'vfio',
>     'virtio',
>     'yank',
>   ]