memory/iommu: QOM'fy IOMMU MemoryRegion

This defines new QOM object - IOMMUMemoryRegion - with MemoryRegion
as a parent.

This moves IOMMU-related fields from MR to IOMMU MR. However to avoid
dymanic QOM casting in fast path (address_space_translate, etc),
this adds an @is_iommu boolean flag to MR and provides new helper to
do simple cast to IOMMU MR - memory_region_get_iommu. The flag
is set in the instance init callback. This defines
memory_region_is_iommu as memory_region_get_iommu()!=NULL.

This switches MemoryRegion to IOMMUMemoryRegion in most places except
the ones where MemoryRegion may be an alias.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Message-Id: <20170711035620.4232-2-aik@ozlabs.ru>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 7 insertions, 5 deletions

diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index 29923e4..c1bb6d4 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -479,6 +479,7 @@ static void vfio_listener_region_add(MemoryListener *listener,
 
     if (memory_region_is_iommu(section->mr)) {
         VFIOGuestIOMMU *giommu;
+        IOMMUMemoryRegion *iommu_mr = IOMMU_MEMORY_REGION(section->mr);
 
         trace_vfio_listener_region_add_iommu(iova, end);
         /*
@@ -488,7 +489,7 @@ static void vfio_listener_region_add(MemoryListener *listener,
          * device emulation the VFIO iommu handles to use).
          */
         giommu = g_malloc0(sizeof(*giommu));
-        giommu->iommu = section->mr;
+        giommu->iommu = iommu_mr;
         giommu->iommu_offset = section->offset_within_address_space -
                                section->offset_within_region;
         giommu->container = container;
@@ -501,7 +502,7 @@ static void vfio_listener_region_add(MemoryListener *listener,
                             int128_get64(llend));
         QLIST_INSERT_HEAD(&container->giommu_list, giommu, giommu_next);
 
-        memory_region_register_iommu_notifier(giommu->iommu, &giommu->n);
+        memory_region_register_iommu_notifier(section->mr, &giommu->n);
         memory_region_iommu_replay(giommu->iommu, &giommu->n);
 
         return;
@@ -569,9 +570,9 @@ static void vfio_listener_region_del(MemoryListener *listener,
         VFIOGuestIOMMU *giommu;
 
         QLIST_FOREACH(giommu, &container->giommu_list, giommu_next) {
-            if (giommu->iommu == section->mr &&
+            if (MEMORY_REGION(giommu->iommu) == section->mr &&
                 giommu->n.start == section->offset_within_region) {
-                memory_region_unregister_iommu_notifier(giommu->iommu,
+                memory_region_unregister_iommu_notifier(section->mr,
                                                         &giommu->n);
                 QLIST_REMOVE(giommu, giommu_next);
                 g_free(giommu);
@@ -1163,7 +1164,8 @@ static void vfio_disconnect_container(VFIOGroup *group)
         QLIST_REMOVE(container, next);
 
         QLIST_FOREACH_SAFE(giommu, &container->giommu_list, giommu_next, tmp) {
-            memory_region_unregister_iommu_notifier(giommu->iommu, &giommu->n);
+            memory_region_unregister_iommu_notifier(
+                    MEMORY_REGION(giommu->iommu), &giommu->n);
             QLIST_REMOVE(giommu, giommu_next);
             g_free(giommu);
         }