[8/8] qom: Use qlit to represent property defaults

diff --git a/include/hw/qdev-properties-system.h b/include/hw/qdev-properties-system.h
index 0ac327ae60..a586424a33 100644
--- a/include/hw/qdev-properties-system.h
+++ b/include/hw/qdev-properties-system.h
@@ -65,7 +65,7 @@  extern const PropertyInfo qdev_prop_pcie_link_width;
 
 #define DEFINE_PROP_UUID(_name, _state, _field) \
     DEFINE_PROP(_name, _state, _field, qdev_prop_uuid, QemuUUID, \
-                .set_default = true)
+                .defval = QLIT_QSTR("auto"))
 
 #define DEFINE_PROP_AUDIODEV(_n, _s, _f) \
     DEFINE_PROP(_n, _s, _f, qdev_prop_audiodev, QEMUSoundCard)
diff --git a/include/qom/field-property-internal.h b/include/qom/field-property-internal.h
index 7aa27ce836..09877d9d6f 100644
--- a/include/qom/field-property-internal.h
+++ b/include/qom/field-property-internal.h
@@ -15,10 +15,6 @@  void field_prop_set_enum(Object *obj, Visitor *v, const char *name,
 
 void field_prop_set_default_value_enum(ObjectProperty *op,
                                        const Property *prop);
-void field_prop_set_default_value_int(ObjectProperty *op,
-                                      const Property *prop);
-void field_prop_set_default_value_uint(ObjectProperty *op,
-                                       const Property *prop);
 
 void field_prop_get_int32(Object *obj, Visitor *v, const char *name,
                           void *opaque, Error **errp);
diff --git a/include/qom/field-property.h b/include/qom/field-property.h
index bc866e1c93..b83b424a5e 100644
--- a/include/qom/field-property.h
+++ b/include/qom/field-property.h
@@ -6,6 +6,7 @@ 
 
 #include "qom/object.h"
 #include "qapi/util.h"
+#include "qapi/qmp/qlit.h"
 
 /**
  * struct Property: definition of a field property
@@ -29,21 +30,8 @@  struct Property {
     const PropertyInfo *info;
     ptrdiff_t    offset;
     uint8_t      bitnr;
-    /**
-     * @set_default: true if the default value should be set from @defval,
-     *    in which case @info->set_default_value must not be NULL
-     *    (if false then no default value is set by the property system
-     *     and the field retains whatever value it was given by instance_init).
-     */
-    bool         set_default;
-    /**
-     * @defval: default value for the property. This is used only if @set_default
-     *     is true.
-     */
-    union {
-        int64_t i;
-        uint64_t u;
-    } defval;
+    /** @defval: If not QNull, the default value for the property */
+    QLitObject defval;
     /* private: */
     int          arrayoffset;
     const PropertyInfo *arrayinfo;
@@ -63,7 +51,13 @@  struct PropertyInfo {
     const QEnumLookup *enum_table;
     /** @print: String formatting function, for the human monitor */
     int (*print)(Object *obj, Property *prop, char *dest, size_t len);
-    /** @set_default_value: Callback for initializing the default value */
+    /**
+     * @set_default_value: Optional callback for initializing the default value
+     *
+     * Most property types don't need to set this, as by default
+     * object_property_set_default() is called with the value at
+     * Property.defval.
+     */
     void (*set_default_value)(ObjectProperty *op, const Property *prop);
     /** @create: Optional callback for creation of property */
     ObjectProperty *(*create)(ObjectClass *oc, const char *name,
diff --git a/include/qom/property-types.h b/include/qom/property-types.h
index 3a36e1fec5..36ca6f9e55 100644
--- a/include/qom/property-types.h
+++ b/include/qom/property-types.h
@@ -5,6 +5,7 @@ 
 #define QOM_PROPERTY_TYPES_H
 
 #include "qom/field-property.h"
+#include "qapi/qmp/qlit.h"
 
 extern const PropertyInfo prop_info_bit;
 extern const PropertyInfo prop_info_bit64;
@@ -28,13 +29,14 @@  extern const PropertyInfo prop_info_link;
         .info      = &(_prop),                                   \
         .offset    = offsetof(_state, _field)                    \
             + type_check(_type, typeof_field(_state, _field)),   \
+        .defval = QLIT_QNULL,                                    \
+        /* Note that __VA_ARGS__ can still override .defval */   \
         __VA_ARGS__                                              \
         }
 
 #define DEFINE_PROP_SIGNED(_name, _state, _field, _defval, _prop, _type) \
     DEFINE_PROP(_name, _state, _field, _prop, _type,                     \
-                .set_default = true,                                     \
-                .defval.i    = (_type)_defval)
+                .defval = QLIT_QNUM_INT(_defval))
 
 #define DEFINE_PROP_SIGNED_NODEFAULT(_name, _state, _field, _prop, _type) \
     DEFINE_PROP(_name, _state, _field, _prop, _type)
@@ -50,13 +52,11 @@  extern const PropertyInfo prop_info_link;
 #define DEFINE_PROP_BIT(_name, _state, _field, _bit, _defval)   \
     DEFINE_PROP(_name, _state, _field, prop_info_bit, uint32_t, \
                 .bitnr       = (_bit),                          \
-                .set_default = true,                            \
-                .defval.u    = (bool)_defval)
+                .defval = QLIT_QBOOL(_defval))
 
 #define DEFINE_PROP_UNSIGNED(_name, _state, _field, _defval, _prop, _type) \
     DEFINE_PROP(_name, _state, _field, _prop, _type,                       \
-                .set_default = true,                                       \
-                .defval.u  = (_type)_defval)
+                .defval = QLIT_QNUM_UINT(_defval))
 
 #define DEFINE_PROP_UNSIGNED_NODEFAULT(_name, _state, _field, _prop, _type) \
     DEFINE_PROP(_name, _state, _field, _prop, _type)
@@ -72,8 +72,7 @@  extern const PropertyInfo prop_info_link;
 #define DEFINE_PROP_BIT64(_name, _state, _field, _bit, _defval)   \
     DEFINE_PROP(_name, _state, _field, prop_info_bit64, uint64_t, \
                 .bitnr    = (_bit),                               \
-                .set_default = true,                              \
-                .defval.u  = (bool)_defval)
+                .defval = QLIT_QBOOL(_defval))
 
 /**
  * DEFINE_PROP_BOOL:
@@ -84,8 +83,7 @@  extern const PropertyInfo prop_info_link;
  */
 #define DEFINE_PROP_BOOL(_name, _state, _field, _defval)     \
     DEFINE_PROP(_name, _state, _field, prop_info_bool, bool, \
-                .set_default = true,                         \
-                .defval.u    = (bool)_defval)
+                .defval = QLIT_QBOOL(_defval))
 
 #define PROP_ARRAY_LEN_PREFIX "len-"
 
@@ -118,8 +116,7 @@  extern const PropertyInfo prop_info_link;
                           _arrayfield, _arrayprop, _arraytype) \
     DEFINE_PROP((PROP_ARRAY_LEN_PREFIX _name),                 \
                 _state, _field, prop_info_arraylen, uint32_t,  \
-                .set_default = true,                           \
-                .defval.u = 0,                                 \
+                .defval = QLIT_QNUM_UINT(0),                   \
                 .arrayinfo = &(_arrayprop),                    \
                 .arrayfieldsize = sizeof(_arraytype),          \
                 .arrayoffset = offsetof(_state, _arrayfield))
diff --git a/hw/core/qdev-properties-system.c b/hw/core/qdev-properties-system.c
index 8da68f076c..d9be5372f6 100644
--- a/hw/core/qdev-properties-system.c
+++ b/hw/core/qdev-properties-system.c
@@ -570,7 +570,6 @@  const PropertyInfo qdev_prop_blocksize = {
                    " and " MAX_BLOCK_SIZE_STR,
     .get   = field_prop_get_size32,
     .set   = set_blocksize,
-    .set_default_value = field_prop_set_default_value_uint,
 };
 
 /* --- Block device error handling policy --- */
@@ -768,7 +767,6 @@  const PropertyInfo qdev_prop_pci_devfn = {
     .print = print_pci_devfn,
     .get   = field_prop_get_int32,
     .set   = set_pci_devfn,
-    .set_default_value = field_prop_set_default_value_int,
 };
 
 /* --- pci host address --- */
@@ -1080,16 +1078,10 @@  static void set_uuid(Object *obj, Visitor *v, const char *name, void *opaque,
     g_free(str);
 }
 
-static void set_default_uuid_auto(ObjectProperty *op, const Property *prop)
-{
-    object_property_set_default_str(op, UUID_VALUE_AUTO);
-}
-
 const PropertyInfo qdev_prop_uuid = {
     .name  = "str",
     .description = "UUID (aka GUID) or \"" UUID_VALUE_AUTO
         "\" for random value (default)",
     .get   = get_uuid,
     .set   = set_uuid,
-    .set_default_value = set_default_uuid_auto,
 };
diff --git a/qom/field-property.c b/qom/field-property.c
index 25a818bb69..727d7199ae 100644
--- a/qom/field-property.c
+++ b/qom/field-property.c
@@ -47,6 +47,20 @@  static ObjectPropertyAccessor *field_prop_setter(const PropertyInfo *info)
     return info->set ? field_prop_set : NULL;
 }
 
+static void field_prop_set_default_value(ObjectProperty *op,
+                                         Property *prop)
+{
+    if (qlit_type(&prop->defval) == QTYPE_QNULL) {
+        return;
+    }
+
+    if (prop->info->set_default_value) {
+        prop->info->set_default_value(op, prop);
+    } else {
+        object_property_set_default(op, qobject_from_qlit(&prop->defval));
+    }
+}
+
 ObjectProperty *
 object_property_add_field(Object *obj, const char *name, Property *prop,
                           ObjectPropertyAllowSet allow_set)
@@ -65,11 +79,9 @@  object_property_add_field(Object *obj, const char *name, Property *prop,
     object_property_set_description(obj, name,
                                     prop->info->description);
 
-    if (prop->set_default) {
-        prop->info->set_default_value(op, prop);
-        if (op->init) {
-            op->init(obj, op);
-        }
+    field_prop_set_default_value(op, prop);
+    if (op->init) {
+        op->init(obj, op);
     }
 
     op->allow_set = allow_set;
@@ -95,9 +107,8 @@  object_class_property_add_field(ObjectClass *oc, const char *name,
                                        prop->info->release,
                                        prop);
     }
-    if (prop->set_default) {
-        prop->info->set_default_value(op, prop);
-    }
+
+    field_prop_set_default_value(op, prop);
     if (prop->info->description) {
         object_class_property_set_description(oc, name,
                                               prop->info->description);
diff --git a/qom/property-types.c b/qom/property-types.c
index f566c05ec2..8bed83c712 100644
--- a/qom/property-types.c
+++ b/qom/property-types.c
@@ -28,8 +28,11 @@  void field_prop_set_enum(Object *obj, Visitor *v, const char *name,
 void field_prop_set_default_value_enum(ObjectProperty *op,
                                        const Property *prop)
 {
-    object_property_set_default_str(op,
-        qapi_enum_lookup(prop->info->enum_table, prop->defval.i));
+    QObject *defval = qobject_from_qlit(&prop->defval);
+    const char *str = qapi_enum_lookup(prop->info->enum_table,
+                                       qnum_get_int(qobject_to(QNum, defval)));
+    object_property_set_default_str(op, str);
+    qobject_unref(defval);
 }
 
 const PropertyInfo prop_info_enum = {
@@ -80,17 +83,11 @@  static void prop_set_bit(Object *obj, Visitor *v, const char *name,
     bit_prop_set(obj, prop, value);
 }
 
-static void set_default_value_bool(ObjectProperty *op, const Property *prop)
-{
-    object_property_set_default_bool(op, prop->defval.u);
-}
-
 const PropertyInfo prop_info_bit = {
     .name  = "bool",
     .description = "on/off",
     .get   = prop_get_bit,
     .set   = prop_set_bit,
-    .set_default_value = set_default_value_bool,
 };
 
 /* Bit64 */
@@ -139,7 +136,6 @@  const PropertyInfo prop_info_bit64 = {
     .description = "on/off",
     .get   = prop_get_bit64,
     .set   = prop_set_bit64,
-    .set_default_value = set_default_value_bool,
 };
 
 /* --- bool --- */
@@ -166,7 +162,6 @@  const PropertyInfo prop_info_bool = {
     .name  = "bool",
     .get   = get_bool,
     .set   = set_bool,
-    .set_default_value = set_default_value_bool,
 };
 
 /* --- 8bit integer --- */
@@ -189,23 +184,10 @@  static void set_uint8(Object *obj, Visitor *v, const char *name, void *opaque,
     visit_type_uint8(v, name, ptr, errp);
 }
 
-void field_prop_set_default_value_int(ObjectProperty *op,
-                                      const Property *prop)
-{
-    object_property_set_default_int(op, prop->defval.i);
-}
-
-void field_prop_set_default_value_uint(ObjectProperty *op,
-                                       const Property *prop)
-{
-    object_property_set_default_uint(op, prop->defval.u);
-}
-
 const PropertyInfo prop_info_uint8 = {
     .name  = "uint8",
     .get   = get_uint8,
     .set   = set_uint8,
-    .set_default_value = field_prop_set_default_value_uint,
 };
 
 /* --- 16bit integer --- */
@@ -232,7 +214,6 @@  const PropertyInfo prop_info_uint16 = {
     .name  = "uint16",
     .get   = get_uint16,
     .set   = set_uint16,
-    .set_default_value = field_prop_set_default_value_uint,
 };
 
 /* --- 32bit integer --- */
@@ -277,14 +258,12 @@  const PropertyInfo prop_info_uint32 = {
     .name  = "uint32",
     .get   = get_uint32,
     .set   = set_uint32,
-    .set_default_value = field_prop_set_default_value_uint,
 };
 
 const PropertyInfo prop_info_int32 = {
     .name  = "int32",
     .get   = field_prop_get_int32,
     .set   = set_int32,
-    .set_default_value = field_prop_set_default_value_int,
 };
 
 /* --- 64bit integer --- */
@@ -329,14 +308,12 @@  const PropertyInfo prop_info_uint64 = {
     .name  = "uint64",
     .get   = get_uint64,
     .set   = set_uint64,
-    .set_default_value = field_prop_set_default_value_uint,
 };
 
 const PropertyInfo prop_info_int64 = {
     .name  = "int64",
     .get   = get_int64,
     .set   = set_int64,
-    .set_default_value = field_prop_set_default_value_int,
 };
 
 /* --- string --- */
@@ -431,7 +408,6 @@  const PropertyInfo prop_info_size32 = {
     .name  = "size",
     .get = field_prop_get_size32,
     .set = set_size32,
-    .set_default_value = field_prop_set_default_value_uint,
 };
 
 /* --- support for array properties --- */
@@ -494,7 +470,6 @@  const PropertyInfo prop_info_arraylen = {
     .name = "uint32",
     .get = get_uint32,
     .set = set_prop_arraylen,
-    .set_default_value = field_prop_set_default_value_uint,
 };
 
 /* --- 64bit unsigned int 'size' type --- */
@@ -521,7 +496,6 @@  const PropertyInfo prop_info_size = {
     .name  = "size",
     .get = get_size,
     .set = set_size,
-    .set_default_value = field_prop_set_default_value_uint,
 };
 
 /* --- object link property --- */