vfio/container: Introduce a VFIOIOMMU legacy QOM interface

Convert the legacy VFIOIOMMUOps struct to the new VFIOIOMMU QOM
interface. The set of of operations for this backend can be referenced
with a literal typename instead of a C struct. This will simplify
support of multiple backends.

Reviewed-by: Zhenzhong Duan <zhenzhong.duan@intel.com>
Tested-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Cédric Le Goater <clg@redhat.com>

2 files changed, 54 insertions, 10 deletions

diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index 49dab41..2329d0e 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -1503,13 +1503,17 @@ retry:
 int vfio_attach_device(char *name, VFIODevice *vbasedev,
                        AddressSpace *as, Error **errp)
 {
-    const VFIOIOMMUClass *ops = &vfio_legacy_ops;
+    const VFIOIOMMUClass *ops =
+        VFIO_IOMMU_CLASS(object_class_by_name(TYPE_VFIO_IOMMU_LEGACY));
 
 #ifdef CONFIG_IOMMUFD
     if (vbasedev->iommufd) {
         ops = &vfio_iommufd_ops;
     }
 #endif
+
+    assert(ops);
+
     return ops->attach_device(name, vbasedev, as, errp);
 }
 
diff --git a/hw/vfio/container.c b/hw/vfio/container.c
index f4a0434..220e838 100644
--- a/hw/vfio/container.c
+++ b/hw/vfio/container.c
@@ -369,10 +369,30 @@ static int vfio_get_iommu_type(VFIOContainer *container,
     return -EINVAL;
 }
 
+/*
+ * vfio_get_iommu_ops - get a VFIOIOMMUClass associated with a type
+ */
+static const VFIOIOMMUClass *vfio_get_iommu_class(int iommu_type, Error **errp)
+{
+    ObjectClass *klass = NULL;
+
+    switch (iommu_type) {
+    case VFIO_TYPE1v2_IOMMU:
+    case VFIO_TYPE1_IOMMU:
+        klass = object_class_by_name(TYPE_VFIO_IOMMU_LEGACY);
+        break;
+    default:
+        g_assert_not_reached();
+    };
+
+    return VFIO_IOMMU_CLASS(klass);
+}
+
 static int vfio_init_container(VFIOContainer *container, int group_fd,
                                VFIOAddressSpace *space, Error **errp)
 {
     int iommu_type, ret;
+    const VFIOIOMMUClass *vioc;
 
     iommu_type = vfio_get_iommu_type(container, errp);
     if (iommu_type < 0) {
@@ -401,7 +421,14 @@ static int vfio_init_container(VFIOContainer *container, int group_fd,
     }
 
     container->iommu_type = iommu_type;
-    vfio_container_init(&container->bcontainer, space, &vfio_legacy_ops);
+
+    vioc = vfio_get_iommu_class(iommu_type, errp);
+    if (!vioc) {
+        error_setg(errp, "No available IOMMU models");
+        return -EINVAL;
+    }
+
+    vfio_container_init(&container->bcontainer, space, vioc);
     return 0;
 }
 
@@ -1098,12 +1125,25 @@ out_single:
     return ret;
 }
 
-const VFIOIOMMUOps vfio_legacy_ops = {
-    .dma_map = vfio_legacy_dma_map,
-    .dma_unmap = vfio_legacy_dma_unmap,
-    .attach_device = vfio_legacy_attach_device,
-    .detach_device = vfio_legacy_detach_device,
-    .set_dirty_page_tracking = vfio_legacy_set_dirty_page_tracking,
-    .query_dirty_bitmap = vfio_legacy_query_dirty_bitmap,
-    .pci_hot_reset = vfio_legacy_pci_hot_reset,
+static void vfio_iommu_legacy_class_init(ObjectClass *klass, void *data)
+{
+    VFIOIOMMUClass *vioc = VFIO_IOMMU_CLASS(klass);
+
+    vioc->dma_map = vfio_legacy_dma_map;
+    vioc->dma_unmap = vfio_legacy_dma_unmap;
+    vioc->attach_device = vfio_legacy_attach_device;
+    vioc->detach_device = vfio_legacy_detach_device;
+    vioc->set_dirty_page_tracking = vfio_legacy_set_dirty_page_tracking;
+    vioc->query_dirty_bitmap = vfio_legacy_query_dirty_bitmap;
+    vioc->pci_hot_reset = vfio_legacy_pci_hot_reset;
 };
+
+static const TypeInfo types[] = {
+    {
+        .name = TYPE_VFIO_IOMMU_LEGACY,
+        .parent = TYPE_VFIO_IOMMU,
+        .class_init = vfio_iommu_legacy_class_init,
+    },
+};
+
+DEFINE_TYPES(types)