iommu_host_domain
void *iommu_host_domain(void);
error = iommu_remove_device(iommu_host_domain(), dev, pci_get_rid(dev));
if (iommu_host_domain() != NULL) {
error = iommu_add_device(iommu_host_domain(), dev,
error = iommu_invalidate_tlb(iommu_host_domain());