Function probe_host_nvidia_vfio_readiness

crates/openshell-vfio/src/gpu.rs:27–77

Scan sysfs for NVIDIA GPUs eligible for VFIO passthrough.

(sysfs: &SysfsRoot)

/// Scan sysfs for NVIDIA GPUs eligible for VFIO passthrough.
pub fn probe_host_nvidia_vfio_readiness(sysfs: &SysfsRoot) -> Vec<PciInfo> {
    let devices_dir = sysfs.pci_devices_dir();
    let entries = match fs::read_dir(&devices_dir) {
        Ok(e) => e,
        Err(err) => {
            tracing::warn!(path = %devices_dir.display(), %err, "cannot read PCI devices directory");
            return Vec::new();
        }
    };

    let mut gpus = Vec::new();

    for entry in entries.filter_map(Result::ok) {
        let bdf = entry.file_name().to_string_lossy().into_owned();
        let device = sysfs.pci_device_ref(&bdf);

        let Ok(vendor) = device.vendor() else {
            continue;
        };
        if vendor != NVIDIA_VENDOR_ID {
            continue;
        }

        let Ok(class) = device.class() else {
            continue;
        };
        if !is_gpu_class(&class) {
            continue;
        }

        let device_id = device.device_id().unwrap_or_default();

        let name = device
            .read_trimmed("label")
            .unwrap_or_else(|_| format!("NVIDIA {device_id}"));

        let Ok(iommu_group) = sysfs.iommu_group(&bdf) else {
            continue;
        };

        gpus.push(PciInfo {
            bdf,
            name,
            vendor,
            device: device_id,
            iommu_group,
        });
    }

    gpus
}

/// Bind a GPU to `vfio-pci`, returning an RAII guard that restores it on drop.
///