hw/misc/macio: Use object_initialize_child for correct ref. counting
authorPhilippe Mathieu-Daudé <philmd@redhat.com>
Tue, 7 May 2019 16:34:02 +0000 (18:34 +0200)
committerEduardo Habkost <ehabkost@redhat.com>
Fri, 24 May 2019 18:29:02 +0000 (15:29 -0300)
As explained in commit aff39be0ed97:

  Both functions, object_initialize() and object_property_add_child()
  increase the reference counter of the new object, so one of the
  references has to be dropped afterwards to get the reference
  counting right. Otherwise the child object will not be properly
  cleaned up when the parent gets destroyed.
  Thus let's use now object_initialize_child() instead to get the
  reference counting here right.

This patch was generated using the following Coccinelle script
(with a bit of manual fix-up for overly long lines):

 @use_object_initialize_child@
 expression parent_obj;
 expression child_ptr;
 expression child_name;
 expression child_type;
 expression child_size;
 expression errp;
 @@
 (
 -   object_initialize(child_ptr, child_size, child_type);
 +   object_initialize_child(parent_obj, child_name,  child_ptr, child_size,
 +                           child_type, &error_abort, NULL);
     ... when != parent_obj
 -   object_property_add_child(parent_obj, child_name, OBJECT(child_ptr), NULL);
     ...
 ?-  object_unref(OBJECT(child_ptr));
 |
 -   object_initialize(child_ptr, child_size, child_type);
 +   object_initialize_child(parent_obj, child_name,  child_ptr, child_size,
 +                            child_type, errp, NULL);
     ... when != parent_obj
 -   object_property_add_child(parent_obj, child_name, OBJECT(child_ptr), errp);
     ...
 ?-  object_unref(OBJECT(child_ptr));
 )

While the object_initialize() function doesn't take an
'Error *errp' argument, the object_initialize_child() does.
Since this code is used when a machine is created (and is not
yet running), we deliberately choose to use the &error_abort
argument instead of ignoring errors if an object creation failed.

Suggested-by: Eduardo Habkost <ehabkost@redhat.com>
Inspired-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20190507163416.24647-3-philmd@redhat.com>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
hw/misc/macio/macio.c

index 94da85c8d7d7a7674bfb25a9adbd45a18e1ca1e5..b726c73022cd8d63f0a70d6d3befc9ff5119bce9 100644 (file)
@@ -346,12 +346,12 @@ static void macio_newworld_realize(PCIDevice *d, Error **errp)
         object_property_set_bool(OBJECT(&ns->gpio), true, "realized", &err);
 
         /* PMU */
-        object_initialize(&s->pmu, sizeof(s->pmu), TYPE_VIA_PMU);
+        object_initialize_child(OBJECT(s), "pmu", &s->pmu, sizeof(s->pmu),
+                                TYPE_VIA_PMU, &error_abort, NULL);
         object_property_set_link(OBJECT(&s->pmu), OBJECT(sysbus_dev), "gpio",
                                  &error_abort);
         qdev_prop_set_bit(DEVICE(&s->pmu), "has-adb", ns->has_adb);
         qdev_set_parent_bus(DEVICE(&s->pmu), BUS(&s->macio_bus));
-        object_property_add_child(OBJECT(s), "pmu", OBJECT(&s->pmu), NULL);
 
         object_property_set_bool(OBJECT(&s->pmu), true, "realized", &err);
         if (err) {
@@ -365,9 +365,9 @@ static void macio_newworld_realize(PCIDevice *d, Error **errp)
                                     sysbus_mmio_get_region(sysbus_dev, 0));
     } else {
         /* CUDA */
-        object_initialize(&s->cuda, sizeof(s->cuda), TYPE_CUDA);
+        object_initialize_child(OBJECT(s), "cuda", &s->cuda, sizeof(s->cuda),
+                                TYPE_CUDA, &error_abort, NULL);
         qdev_set_parent_bus(DEVICE(&s->cuda), BUS(&s->macio_bus));
-        object_property_add_child(OBJECT(s), "cuda", OBJECT(&s->cuda), NULL);
         qdev_prop_set_uint64(DEVICE(&s->cuda), "timebase-frequency",
                              s->frequency);