If devices are to be skipped anyway (which is the case in particular for host bridges), there's no point complaining about a missing DRHD (and hence a missing association with an IOMMU).
While there convert assignments to initializers and constify "drhd" local variables. Signed-off-by: Jan Beulich <[email protected]> --- a/xen/drivers/passthrough/vtd/iommu.c +++ b/xen/drivers/passthrough/vtd/iommu.c @@ -1460,14 +1460,10 @@ static int domain_context_unmap(struct d static int domain_context_mapping(struct domain *domain, u8 devfn, struct pci_dev *pdev) { - struct acpi_drhd_unit *drhd; + const struct acpi_drhd_unit *drhd = acpi_find_matched_drhd_unit(pdev); int ret = 0; u8 seg = pdev->seg, bus = pdev->bus, secbus; - drhd = acpi_find_matched_drhd_unit(pdev); - if ( !drhd ) - return -ENODEV; - /* * Generally we assume only devices from one node to get assigned to a * given guest. But even if not, by replacing the prior value here we @@ -1476,7 +1472,7 @@ static int domain_context_mapping(struct * this or other devices may be penalized then, but some would also be * if we left other than NUMA_NO_NODE untouched here. */ - if ( drhd->iommu->node != NUMA_NO_NODE ) + if ( drhd && drhd->iommu->node != NUMA_NO_NODE ) dom_iommu(domain)->node = drhd->iommu->node; ASSERT(pcidevs_locked()); @@ -1497,6 +1493,9 @@ static int domain_context_mapping(struct break; case DEV_TYPE_PCIe_ENDPOINT: + if ( !drhd ) + return -ENODEV; + if ( iommu_debug ) printk(VTDPREFIX "%pd:PCIe: map %pp\n", domain, &PCI_SBDF3(seg, bus, devfn)); @@ -1508,6 +1507,9 @@ static int domain_context_mapping(struct break; case DEV_TYPE_PCI: + if ( !drhd ) + return -ENODEV; + if ( iommu_debug ) printk(VTDPREFIX "%pd:PCI: map %pp\n", domain, &PCI_SBDF3(seg, bus, devfn)); @@ -1651,17 +1653,12 @@ int domain_context_unmap_one( static int domain_context_unmap(struct domain *domain, u8 devfn, struct pci_dev *pdev) { - struct acpi_drhd_unit *drhd; - struct vtd_iommu *iommu; + const struct acpi_drhd_unit *drhd = acpi_find_matched_drhd_unit(pdev); + struct vtd_iommu *iommu = drhd ? drhd->iommu : NULL; int ret; u8 seg = pdev->seg, bus = pdev->bus, tmp_bus, tmp_devfn, secbus; int found = 0; - drhd = acpi_find_matched_drhd_unit(pdev); - if ( !drhd ) - return -ENODEV; - iommu = drhd->iommu; - switch ( pdev->type ) { case DEV_TYPE_PCI_HOST_BRIDGE: @@ -1676,6 +1673,9 @@ static int domain_context_unmap(struct d return 0; case DEV_TYPE_PCIe_ENDPOINT: + if ( !iommu ) + return -ENODEV; + if ( iommu_debug ) printk(VTDPREFIX "%pd:PCIe: unmap %pp\n", domain, &PCI_SBDF3(seg, bus, devfn)); @@ -1686,6 +1686,9 @@ static int domain_context_unmap(struct d break; case DEV_TYPE_PCI: + if ( !iommu ) + return -ENODEV; + if ( iommu_debug ) printk(VTDPREFIX "%pd:PCI: unmap %pp\n", domain, &PCI_SBDF3(seg, bus, devfn));
