ivshmem: Convert to DEFINE_PROP_LINK

Unlike the usual object_property_add_link() invocations in other
devices, ivshmem checks the "is mapped" state of the backend in addition
to qdev_prop_allow_set_link_before_realize. To convert it without
specializing DEFINE_PROP_LINK which always uses the qdev callback, move
the extra check to device realize time.

Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <20170714021509.23681-12-famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

1 files changed, 7 insertions, 17 deletions

diff --git a/hw/misc/ivshmem.c b/hw/misc/ivshmem.c
index 731f3c1d4f..a58f9ee579 100644
--- a/hw/misc/ivshmem.c
+++ b/hw/misc/ivshmem.c
@@ -1009,18 +1009,6 @@ static const TypeInfo ivshmem_common_info = {
     .class_init    = ivshmem_common_class_init,
 };
 
-static void ivshmem_check_memdev_is_busy(const Object *obj, const char *name,
-                                         Object *val, Error **errp)
-{
-    if (host_memory_backend_is_mapped(MEMORY_BACKEND(val))) {
-        char *path = object_get_canonical_path_component(val);
-        error_setg(errp, "can't use already busy memdev: %s", path);
-        g_free(path);
-    } else {
-        qdev_prop_allow_set_link_before_realize(obj, name, val, errp);
-    }
-}
-
 static const VMStateDescription ivshmem_plain_vmsd = {
     .name = TYPE_IVSHMEM_PLAIN,
     .version_id = 0,
@@ -1037,6 +1025,8 @@ static const VMStateDescription ivshmem_plain_vmsd = {
 
 static Property ivshmem_plain_properties[] = {
     DEFINE_PROP_ON_OFF_AUTO("master", IVShmemState, master, ON_OFF_AUTO_OFF),
+    DEFINE_PROP_LINK("memdev", IVShmemState, hostmem, TYPE_MEMORY_BACKEND,
+                     HostMemoryBackend *),
     DEFINE_PROP_END_OF_LIST(),
 };
 
@@ -1044,11 +1034,6 @@ static void ivshmem_plain_init(Object *obj)
 {
     IVShmemState *s = IVSHMEM_PLAIN(obj);
 
-    object_property_add_link(obj, "memdev", TYPE_MEMORY_BACKEND,
-                             (Object **)&s->hostmem,
-                             ivshmem_check_memdev_is_busy,
-                             OBJ_PROP_LINK_UNREF_ON_RELEASE,
-                             &error_abort);
     s->not_legacy_32bit = 1;
 }
 
@@ -1059,6 +1044,11 @@ static void ivshmem_plain_realize(PCIDevice *dev, Error **errp)
     if (!s->hostmem) {
         error_setg(errp, "You must specify a 'memdev'");
         return;
+    } else if (host_memory_backend_is_mapped(s->hostmem)) {
+        char *path = object_get_canonical_path_component(OBJECT(s->hostmem));
+        error_setg(errp, "can't use already busy memdev: %s", path);
+        g_free(path);
+        return;
     }
 
     ivshmem_common_realize(dev, errp);