rust: qom: convert type_info! macro to an associated const

type_info! is only used in the definition of ObjectImpl::TYPE_INFO, and
in fact in all of them.  Pull type_info!'s definition into the ObjectImpl
trait, thus simplifying the external interface of qemu_api::definitions.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

rust/hw/char/pl011/src/device.rs

@@ -106,7 +106,6 @@ pub struct PL011State {
 
 impl ObjectImpl for PL011State {
     type Class = PL011Class;
-    const TYPE_INFO: qemu_api::bindings::TypeInfo = qemu_api::type_info! { Self };
     const TYPE_NAME: &'static CStr = crate::TYPE_PL011;
     const PARENT_TYPE_NAME: Option<&'static CStr> = Some(TYPE_SYS_BUS_DEVICE);
     const INSTANCE_INIT: Option<unsafe extern "C" fn(obj: *mut Object)> = Some(pl011_init);
@@ -149,7 +148,7 @@ impl PL011State {
                 addr_of_mut!(*self).cast::<Object>(),
                 &PL011_OPS,
                 addr_of_mut!(*self).cast::<c_void>(),
-                Self::TYPE_INFO.name,
+                Self::TYPE_NAME.as_ptr(),
                 0x1000,
             );
             sysbus_init_mmio(sbd, addr_of_mut!(self.iomem));
@@ -598,7 +597,7 @@ pub unsafe extern "C" fn pl011_create(
     chr: *mut Chardev,
 ) -> *mut DeviceState {
     unsafe {
-        let dev: *mut DeviceState = qdev_new(PL011State::TYPE_INFO.name);
+        let dev: *mut DeviceState = qdev_new(PL011State::TYPE_NAME.as_ptr());
         let sysbus: *mut SysBusDevice = dev.cast::<SysBusDevice>();
 
         qdev_prop_set_chr(dev, c_str!("chardev").as_ptr(), chr);
@@ -660,7 +659,6 @@ impl qemu_api::definitions::ClassInitImpl for PL011LuminaryClass {
 
 impl ObjectImpl for PL011Luminary {
     type Class = PL011LuminaryClass;
-    const TYPE_INFO: qemu_api::bindings::TypeInfo = qemu_api::type_info! { Self };
     const TYPE_NAME: &'static CStr = crate::TYPE_PL011_LUMINARY;
     const PARENT_TYPE_NAME: Option<&'static CStr> = Some(crate::TYPE_PL011);
     const INSTANCE_INIT: Option<unsafe extern "C" fn(obj: *mut Object)> = Some(pl011_luminary_init);

rust/qemu-api/src/definitions.rs

@@ -9,15 +9,34 @@ use std::{ffi::CStr, os::raw::c_void};
 use crate::bindings::{Object, ObjectClass, TypeInfo};
 
 /// Trait a type must implement to be registered with QEMU.
-pub trait ObjectImpl {
+pub trait ObjectImpl: Sized {
-    type Class;
+    type Class: ClassInitImpl;
-    const TYPE_INFO: TypeInfo;
     const TYPE_NAME: &'static CStr;
     const PARENT_TYPE_NAME: Option<&'static CStr>;
     const ABSTRACT: bool = false;
     const INSTANCE_INIT: Option<unsafe extern "C" fn(obj: *mut Object)> = None;
     const INSTANCE_POST_INIT: Option<unsafe extern "C" fn(obj: *mut Object)> = None;
     const INSTANCE_FINALIZE: Option<unsafe extern "C" fn(obj: *mut Object)> = None;
+
+    const TYPE_INFO: TypeInfo = TypeInfo {
+        name: Self::TYPE_NAME.as_ptr(),
+        parent: if let Some(pname) = Self::PARENT_TYPE_NAME {
+            pname.as_ptr()
+        } else {
+            core::ptr::null_mut()
+        },
+        instance_size: core::mem::size_of::<Self>(),
+        instance_align: core::mem::align_of::<Self>(),
+        instance_init: Self::INSTANCE_INIT,
+        instance_post_init: Self::INSTANCE_POST_INIT,
+        instance_finalize: Self::INSTANCE_FINALIZE,
+        abstract_: Self::ABSTRACT,
+        class_size: core::mem::size_of::<Self::Class>(),
+        class_init: <Self::Class as ClassInitImpl>::CLASS_INIT,
+        class_base_init: <Self::Class as ClassInitImpl>::CLASS_BASE_INIT,
+        class_data: core::ptr::null_mut(),
+        interfaces: core::ptr::null_mut(),
+    };
 }
 
 /// Trait used to fill in a class struct.
@@ -83,28 +102,3 @@ macro_rules! module_init {
         }
     };
 }
-
-#[macro_export]
-macro_rules! type_info {
-    ($t:ty) => {
-        $crate::bindings::TypeInfo {
-            name: <$t as $crate::definitions::ObjectImpl>::TYPE_NAME.as_ptr(),
-            parent: if let Some(pname) = <$t as $crate::definitions::ObjectImpl>::PARENT_TYPE_NAME {
-                pname.as_ptr()
-            } else {
-                ::core::ptr::null_mut()
-            },
-            instance_size: ::core::mem::size_of::<$t>(),
-            instance_align: ::core::mem::align_of::<$t>(),
-            instance_init: <$t as $crate::definitions::ObjectImpl>::INSTANCE_INIT,
-            instance_post_init: <$t as $crate::definitions::ObjectImpl>::INSTANCE_POST_INIT,
-            instance_finalize: <$t as $crate::definitions::ObjectImpl>::INSTANCE_FINALIZE,
-            abstract_: <$t as $crate::definitions::ObjectImpl>::ABSTRACT,
-            class_size:  ::core::mem::size_of::<<$t as $crate::definitions::ObjectImpl>::Class>(),
-            class_init: <<$t as $crate::definitions::ObjectImpl>::Class as $crate::definitions::ClassInitImpl>::CLASS_INIT,
-            class_base_init: <<$t as $crate::definitions::ObjectImpl>::Class as $crate::definitions::ClassInitImpl>::CLASS_BASE_INIT,
-            class_data: ::core::ptr::null_mut(),
-            interfaces: ::core::ptr::null_mut(),
-        };
-    }
-}

rust/qemu-api/tests/tests.rs

@@ -55,7 +55,6 @@ fn test_device_decl_macros() {
 
     impl ObjectImpl for DummyState {
         type Class = DummyClass;
-        const TYPE_INFO: qemu_api::bindings::TypeInfo = qemu_api::type_info! { Self };
         const TYPE_NAME: &'static CStr = c_str!("dummy");
         const PARENT_TYPE_NAME: Option<&'static CStr> = Some(device_class::TYPE_DEVICE);
     }