Method new

virtio-devices/src/vdpa.rs:120–201

(
        id: String,
        device_path: &str,
        mem: GuestMemoryAtomic<GuestMemoryMmap>,
        num_queues: u16,
        state: Option<VdpaState>,
    )

impl Vdpa {
    pub fn new(
        id: String,
        device_path: &str,
        mem: GuestMemoryAtomic<GuestMemoryMmap>,
        num_queues: u16,
        state: Option<VdpaState>,
    ) -> Result<Self> {
        let mut vhost = VhostKernVdpa::new(device_path, mem).map_err(Error::CreateVhostVdpa)?;
        vhost.set_owner().map_err(Error::SetOwner)?;

        let (
            device_type,
            avail_features,
            acked_features,
            queue_sizes,
            iova_range,
            backend_features,
            paused,
        ) = if let Some(state) = state {
            info!("Restoring vDPA {id}");

            vhost.set_backend_features_acked(state.backend_features);
            vhost
                .set_config(0, state.config.as_slice())
                .map_err(Error::SetConfig)?;

            (
                state.device_type,
                state.avail_features,
                state.acked_features,
                state.queue_sizes,
                VhostVdpaIovaRange {
                    first: state.iova_range_first,
                    last: state.iova_range_last,
                },
                state.backend_features,
                false,
            )
        } else {
            let device_type = vhost.get_device_id().map_err(Error::GetDeviceId)?;
            let queue_size = vhost.get_vring_num().map_err(Error::GetVringNum)?;
            let avail_features = vhost.get_features().map_err(Error::GetFeatures)?;
            let backend_features = vhost
                .get_backend_features()
                .map_err(Error::GetBackendFeatures)?;
            vhost.set_backend_features_acked(backend_features);

            let iova_range = vhost.get_iova_range().map_err(Error::GetIovaRange)?;

            if avail_features & (1u64 << VIRTIO_F_ACCESS_PLATFORM) == 0 {
                return Err(Error::MissingAccessPlatformVirtioFeature);
            }

            (
                device_type,
                avail_features,
                0,
                vec![queue_size; num_queues as usize],