[PATCH v7 4/5] virtio-iommu-pci: Add array of Interval properties

[Eric Auger <eric.auger@redhat.com>]

The machine may need to pass reserved regions to the
virtio-iommu-pci device (such as the MSI window on x86
or the MSI doorbells on ARM).

So let's add an array of Interval properties.

Note: if some reserved regions are already set by the
machine code - which should be the case in general -,
the length of the property array is already set and
prevents the end-user from modifying them. For example,
attempting to use:

-device virtio-iommu-pci,\
 len-reserved-regions=1,reserved-regions[0]=0xfee00000:0xfeefffff:1

would result in the following error message:

qemu-system-aarch64: -device virtio-iommu-pci,addr=0xa,
len-reserved-regions=1,reserved-regions[0]=0xfee00000:0xfeefffff:1:
array size property len-reserved-regions may not be set more than once

Otherwise, for example, adding two reserved regions is achieved
using the following options:

-device virtio-iommu-pci,addr=0xa,len-reserved-regions=2,\
 reserved-regions[0]=0xfee00000:0xfeefffff:1,\
 reserved-regions[1]=0x1000000:100ffff:1

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>

---
v6 -> v7:
- fix hint message with correct valid values, ie. 0 and 1
- added Markus' R-b

v5 -> v6:
- check the type value
- removed Jean's R-b

v3 -> v4:
- added examples in the commit message as suggested by Markus
- added Jean's R-b
---
 hw/virtio/virtio-iommu-pci.c | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/hw/virtio/virtio-iommu-pci.c b/hw/virtio/virtio-iommu-pci.c
index 632533abaf..33f3f5b03e 100644
--- a/hw/virtio/virtio-iommu-pci.c
+++ b/hw/virtio/virtio-iommu-pci.c
@@ -33,6 +33,9 @@ struct VirtIOIOMMUPCI {
 
 static Property virtio_iommu_pci_properties[] = {
     DEFINE_PROP_UINT32("class", VirtIOPCIProxy, class_code, 0),
+    DEFINE_PROP_ARRAY("reserved-regions", VirtIOIOMMUPCI,
+                      vdev.nb_reserved_regions, vdev.reserved_regions,
+                      qdev_prop_reserved_region, ReservedRegion),
     DEFINE_PROP_END_OF_LIST(),
 };
 
@@ -40,6 +43,7 @@ static void virtio_iommu_pci_realize(VirtIOPCIProxy *vpci_dev, Error **errp)
 {
     VirtIOIOMMUPCI *dev = VIRTIO_IOMMU_PCI(vpci_dev);
     DeviceState *vdev = DEVICE(&dev->vdev);
+    VirtIOIOMMU *s = VIRTIO_IOMMU(vdev);
 
     if (!qdev_get_machine_hotplug_handler(DEVICE(vpci_dev))) {
         MachineClass *mc = MACHINE_GET_CLASS(qdev_get_machine());
@@ -54,6 +58,13 @@ static void virtio_iommu_pci_realize(VirtIOPCIProxy *vpci_dev, Error **errp)
                           "-no-acpi\n");
         return;
     }
+    for (int i = 0; i < s->nb_reserved_regions; i++) {
+        if (s->reserved_regions[i].type != VIRTIO_IOMMU_RESV_MEM_T_RESERVED &&
+            s->reserved_regions[i].type != VIRTIO_IOMMU_RESV_MEM_T_MSI) {
+            error_setg(errp, "reserved region %d has an invalid type", i);
+            error_append_hint(errp, "Valid values are 0 and 1\n");
+        }
+    }
     object_property_set_link(OBJECT(dev),
                              OBJECT(pci_get_bus(&vpci_dev->pci_dev)),
                              "primary-bus", errp);
-- 
2.20.1