3 files changed, 25 insertions, 4 deletions
diff --git a/backends/hostmem-ram.c b/backends/hostmem-ram.c
index bba2ebcce8..d9a8290dc9 100644
--- a/backends/hostmem-ram.c
+++ b/backends/hostmem-ram.c
@@ -16,9 +16,8 @@
 
 
 static void
-ram_backend_memory_init(UserCreatable *uc, Error **errp)
+ram_backend_memory_alloc(HostMemoryBackend *backend, Error **errp)
 {
-    HostMemoryBackend *backend = MEMORY_BACKEND(uc);
     char *path;
 
     if (!backend->size) {
@@ -35,9 +34,9 @@ ram_backend_memory_init(UserCreatable *uc, Error **errp)
 static void
 ram_backend_class_init(ObjectClass *oc, void *data)
 {
-    UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
+    HostMemoryBackendClass *bc = MEMORY_BACKEND_CLASS(oc);
 
-    ucc->complete = ram_backend_memory_init;
+    bc->alloc = ram_backend_memory_alloc;
 }
 
 static const TypeInfo ram_backend_info = {
diff --git a/backends/hostmem.c b/backends/hostmem.c
index 2d9fd00cb3..1738774895 100644
--- a/backends/hostmem.c
+++ b/backends/hostmem.c
@@ -75,11 +75,31 @@ host_memory_backend_get_memory(HostMemoryBackend *backend, Error **errp)
     return memory_region_size(&backend->mr) ? &backend->mr : NULL;
 }
 
+static void
+host_memory_backend_memory_complete(UserCreatable *uc, Error **errp)
+{
+    HostMemoryBackend *backend = MEMORY_BACKEND(uc);
+    HostMemoryBackendClass *bc = MEMORY_BACKEND_GET_CLASS(uc);
+
+    if (bc->alloc) {
+        bc->alloc(backend, errp);
+    }
+}
+
+static void
+host_memory_backend_class_init(ObjectClass *oc, void *data)
+{
+    UserCreatableClass *ucc = USER_CREATABLE_CLASS(oc);
+
+    ucc->complete = host_memory_backend_memory_complete;
+}
+
 static const TypeInfo host_memory_backend_info = {
     .name = TYPE_MEMORY_BACKEND,
     .parent = TYPE_OBJECT,
     .abstract = true,
     .class_size = sizeof(HostMemoryBackendClass),
+    .class_init = host_memory_backend_class_init,
     .instance_size = sizeof(HostMemoryBackend),
     .instance_init = host_memory_backend_init,
     .instance_finalize = host_memory_backend_finalize,
diff --git a/include/sysemu/hostmem.h b/include/sysemu/hostmem.h
index 4fc081eb17..923f6721d2 100644
--- a/include/sysemu/hostmem.h
+++ b/include/sysemu/hostmem.h
@@ -34,6 +34,8 @@ typedef struct HostMemoryBackendClass HostMemoryBackendClass;
  */
 struct HostMemoryBackendClass {
     ObjectClass parent_class;
+
+    void (*alloc)(HostMemoryBackend *backend, Error **errp);
 };
 
 /**