[Qemu-devel] [PATCH qemu v16 01/19] vfio: Delay DMA address space listener release

[Alexey Kardashevskiy]

This postpones VFIO container deinitialization to let region_del()
callbacks (called via vfio_listener_release) do proper clean up
while the group is still attached to the container.

Signed-off-by: Alexey Kardashevskiy <a...@ozlabs.ru>
---
 hw/vfio/common.c | 22 +++++++++++++++-------
 1 file changed, 15 insertions(+), 7 deletions(-)

diff --git a/hw/vfio/common.c b/hw/vfio/common.c
index fe5ec6a..0b40262 100644
--- a/hw/vfio/common.c
+++ b/hw/vfio/common.c
@@ -921,23 +921,31 @@ static void vfio_disconnect_container(VFIOGroup *group)
 {
     VFIOContainer *container = group->container;
 
-    if (ioctl(group->fd, VFIO_GROUP_UNSET_CONTAINER, &container->fd)) {
-        error_report("vfio: error disconnecting group %d from container",
-                     group->groupid);
-    }
-
     QLIST_REMOVE(group, container_next);
+
+    if (QLIST_EMPTY(&container->group_list)) {
+        VFIOGuestIOMMU *giommu;
+
+        vfio_listener_release(container);
+
+        QLIST_FOREACH(giommu, &container->giommu_list, giommu_next) {
+            memory_region_unregister_iommu_notifier(&giommu->n);
+        }
+    }
+
     group->container = NULL;
+    if (ioctl(group->fd, VFIO_GROUP_UNSET_CONTAINER, &container->fd)) {
+        error_report("vfio: error disconnecting group %d from container",
+                     group->groupid);
+    }
 
     if (QLIST_EMPTY(&container->group_list)) {
         VFIOAddressSpace *space = container->space;
         VFIOGuestIOMMU *giommu, *tmp;
 
-        vfio_listener_release(container);
         QLIST_REMOVE(container, next);
 
         QLIST_FOREACH_SAFE(giommu, &container->giommu_list, giommu_next, tmp) {
-            memory_region_unregister_iommu_notifier(&giommu->n);
             QLIST_REMOVE(giommu, giommu_next);
             g_free(giommu);
         }
-- 
2.5.0.rc3