[PATCH 3/3] virtio-iommu: Support PCI device aliases

[Zhenzhong Duan]

Currently virtio-iommu doesn't work well if there are multiple devices
in same iommu group. In below example config, guest virtio-iommu driver
can successfully probe first device but fail on others. Only one device
under the bridge can work normally.

-device virtio-iommu \
-device pcie-pci-bridge,id=root0 \
-device vfio-pci,host=81:11.0,bus=root0 \
-device vfio-pci,host=6f:01.0,bus=root0 \

The reason is virtio-iommu stores AS(address space) in hash table with
aliased BDF and corelates endpoint which is indexed by device's real
BDF, i.e., virtio_iommu_mr() is passed a real BDF to lookup AS hash
table, we either get wrong AS or NULL.

Fix it by storing AS indexed by real BDF. This way also make iova_ranges
from vfio device stored in IOMMUDevice of real BDF successfully.

Signed-off-by: Zhenzhong Duan <zhenzhong.d...@intel.com>
---
 hw/virtio/virtio-iommu.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/hw/virtio/virtio-iommu.c b/hw/virtio/virtio-iommu.c
index d99c1f0d64..6880d92a44 100644
--- a/hw/virtio/virtio-iommu.c
+++ b/hw/virtio/virtio-iommu.c
@@ -399,27 +399,27 @@ static AddressSpace *virtio_iommu_find_add_as(PCIBus 
*bus, void *opaque,
                                               int real_devfn)
 {
     VirtIOIOMMU *s = opaque;
-    IOMMUPciBus *sbus = g_hash_table_lookup(s->as_by_busptr, bus);
+    IOMMUPciBus *sbus = g_hash_table_lookup(s->as_by_busptr, real_bus);
     static uint32_t mr_index;
     IOMMUDevice *sdev;
 
     if (!sbus) {
         sbus = g_malloc0(sizeof(IOMMUPciBus) +
                          sizeof(IOMMUDevice *) * PCI_DEVFN_MAX);
-        sbus->bus = bus;
-        g_hash_table_insert(s->as_by_busptr, bus, sbus);
+        sbus->bus = real_bus;
+        g_hash_table_insert(s->as_by_busptr, real_bus, sbus);
     }
 
-    sdev = sbus->pbdev[devfn];
+    sdev = sbus->pbdev[real_devfn];
     if (!sdev) {
         char *name = g_strdup_printf("%s-%d-%d",
                                      TYPE_VIRTIO_IOMMU_MEMORY_REGION,
-                                     mr_index++, devfn);
-        sdev = sbus->pbdev[devfn] = g_new0(IOMMUDevice, 1);
+                                     mr_index++, real_devfn);
+        sdev = sbus->pbdev[real_devfn] = g_new0(IOMMUDevice, 1);
 
         sdev->viommu = s;
-        sdev->bus = bus;
-        sdev->devfn = devfn;
+        sdev->bus = real_bus;
+        sdev->devfn = real_devfn;
 
         trace_virtio_iommu_init_iommu_mr(name);
 
-- 
2.34.1