On 30/04/2024 06:16, Avihai Horon wrote:
> Emit VFIO device migration state change QAPI event when a VFIO device
> changes its migration state. This can be used by management applications
> to get updates on the current state of the VFIO device for their own
> purposes.
>
> A new per VFIO device capability, "migration-events", is added so events
> can be enabled only for the required devices. It is disabled by default.
>
> Signed-off-by: Avihai Horon <avih...@nvidia.com>
> ---
> include/hw/vfio/vfio-common.h | 1 +
> hw/vfio/migration.c | 44 +++++++++++++++++++++++++++++++++++
> hw/vfio/pci.c | 2 ++
> 3 files changed, 47 insertions(+)
>
> diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
> index b9da6c08ef..3ec5f2425e 100644
> --- a/include/hw/vfio/vfio-common.h
> +++ b/include/hw/vfio/vfio-common.h
> @@ -115,6 +115,7 @@ typedef struct VFIODevice {
> bool no_mmap;
> bool ram_block_discard_allowed;
> OnOffAuto enable_migration;
> + bool migration_events;
> VFIODeviceOps *ops;
> unsigned int num_irqs;
> unsigned int num_regions;
> diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c
> index 06ae40969b..6bbccf6545 100644
> --- a/hw/vfio/migration.c
> +++ b/hw/vfio/migration.c
> @@ -24,6 +24,7 @@
> #include "migration/register.h"
> #include "migration/blocker.h"
> #include "qapi/error.h"
> +#include "qapi/qapi-events-vfio.h"
> #include "exec/ramlist.h"
> #include "exec/ram_addr.h"
> #include "pci.h"
> @@ -80,6 +81,46 @@ static const char *mig_state_to_str(enum
> vfio_device_mig_state state)
> }
> }
>
> +static VFIODeviceMigState
> +mig_state_to_qapi_state(enum vfio_device_mig_state state)
> +{
> + switch (state) {
> + case VFIO_DEVICE_STATE_STOP:
> + return QAPI_VFIO_DEVICE_MIG_STATE_STOP;
> + case VFIO_DEVICE_STATE_RUNNING:
> + return QAPI_VFIO_DEVICE_MIG_STATE_RUNNING;
> + case VFIO_DEVICE_STATE_STOP_COPY:
> + return QAPI_VFIO_DEVICE_MIG_STATE_STOP_COPY;
> + case VFIO_DEVICE_STATE_RESUMING:
> + return QAPI_VFIO_DEVICE_MIG_STATE_RESUMING;
> + case VFIO_DEVICE_STATE_RUNNING_P2P:
> + return QAPI_VFIO_DEVICE_MIG_STATE_RUNNING_P2P;
> + case VFIO_DEVICE_STATE_PRE_COPY:
> + return QAPI_VFIO_DEVICE_MIG_STATE_PRE_COPY;
> + case VFIO_DEVICE_STATE_PRE_COPY_P2P:
> + return QAPI_VFIO_DEVICE_MIG_STATE_PRE_COPY_P2P;
> + default:
> + g_assert_not_reached();
> + }
> +}
> +
> +static void vfio_migration_send_state_change_event(VFIODevice *vbasedev)
> +{
> + VFIOMigration *migration = vbasedev->migration;
> + const char *id;
> + Object *obj;
> +
> + if (!vbasedev->migration_events) {
> + return;
> + }
> +
Shouldn't this leap frog migrate_events() capability instead of introducing its
vfio equivalent i.e.
if (!migrate_events()) {
return;
}
?
Applications that don't understand the event string (migration related or not)
will just discard it (AIUI)
> + obj = vbasedev->ops->vfio_get_object(vbasedev);
> + id = object_get_canonical_path_component(obj);
> +
> + qapi_event_send_vfio_device_mig_state_changed(
> + id, mig_state_to_qapi_state(migration->device_state));
> +}
> +
> static int vfio_migration_set_state(VFIODevice *vbasedev,
> enum vfio_device_mig_state new_state,
> enum vfio_device_mig_state recover_state)
> @@ -126,11 +167,13 @@ static int vfio_migration_set_state(VFIODevice
> *vbasedev,
> }
>
> migration->device_state = recover_state;
> + vfio_migration_send_state_change_event(vbasedev);
>
> return ret;
> }
>
> migration->device_state = new_state;
> + vfio_migration_send_state_change_event(vbasedev);
> if (mig_state->data_fd != -1) {
> if (migration->data_fd != -1) {
> /*
> @@ -157,6 +200,7 @@ reset_device:
> }
>
> migration->device_state = VFIO_DEVICE_STATE_RUNNING;
> + vfio_migration_send_state_change_event(vbasedev);
>
> return ret;
> }
> diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
> index 64780d1b79..8840602c50 100644
> --- a/hw/vfio/pci.c
> +++ b/hw/vfio/pci.c
> @@ -3362,6 +3362,8 @@ static Property vfio_pci_dev_properties[] = {
> VFIO_FEATURE_ENABLE_IGD_OPREGION_BIT, false),
> DEFINE_PROP_ON_OFF_AUTO("enable-migration", VFIOPCIDevice,
> vbasedev.enable_migration, ON_OFF_AUTO_AUTO),
> + DEFINE_PROP_BOOL("migration-events", VFIOPCIDevice,
> + vbasedev.migration_events, false),
> DEFINE_PROP_BOOL("x-no-mmap", VFIOPCIDevice, vbasedev.no_mmap, false),
> DEFINE_PROP_BOOL("x-balloon-allowed", VFIOPCIDevice,
> vbasedev.ram_block_discard_allowed, false),
