@@ -125,9 +125,8 @@ fn properties() -> &'static [Property] {
fn vmsd() -> Option<&'static VMStateDescription> {
Some(&device_class::VMSTATE_PL011)
}
- const REALIZE: Option<unsafe extern "C" fn(*mut DeviceState, *mut *mut Error)> =
- Some(device_class::pl011_realize);
- const RESET: Option<unsafe extern "C" fn(*mut DeviceState)> = Some(device_class::pl011_reset);
+ const REALIZE: Option<fn(&mut Self)> = Some(Self::realize);
+ const RESET: Option<fn(&mut Self)> = Some(Self::reset);
}
impl_device_class!(PL011State);
@@ -92,29 +92,3 @@ extern "C" fn pl011_post_load(opaque: *mut c_void, version_id: c_int) -> c_int {
default = true
),
}
-
-/// # Safety
-///
-/// We expect the FFI user of this function to pass a valid pointer, that has
-/// the same size as [`PL011State`]. We also expect the device is
-/// readable/writeable from one thread at any time.
-pub unsafe extern "C" fn pl011_realize(dev: *mut DeviceState, _errp: *mut *mut Error) {
- unsafe {
- assert!(!dev.is_null());
- let mut state = NonNull::new_unchecked(dev.cast::<PL011State>());
- state.as_mut().realize();
- }
-}
-
-/// # Safety
-///
-/// We expect the FFI user of this function to pass a valid pointer, that has
-/// the same size as [`PL011State`]. We also expect the device is
-/// readable/writeable from one thread at any time.
-pub unsafe extern "C" fn pl011_reset(dev: *mut DeviceState) {
- unsafe {
- assert!(!dev.is_null());
- let mut state = NonNull::new_unchecked(dev.cast::<PL011State>());
- state.as_mut().reset();
- }
-}
@@ -47,7 +47,7 @@ pub trait ObjectImpl: ClassInitImpl + Sized {
/// Each QOM type has one such class struct.
///
/// The Rust implementation of methods will usually come from a trait
-/// like [`ObjectImpl`].
+/// like [`ObjectImpl`] or [`DeviceImpl`](crate::device_class::DeviceImpl).
pub trait ClassInitImpl {
/// Function that is called after all parent class initialization
/// has occurred. On entry, the virtual method pointers are set to
@@ -8,6 +8,7 @@
self, DeviceClass, DeviceState, Error, ObjectClass, Property, VMStateDescription,
};
+/// Trait providing the contents of [`DeviceClass`].
pub trait DeviceImpl {
/// _Realization_ is the second stage of device creation. It contains
/// all operations that depend on device properties and can fail (note:
@@ -15,14 +16,14 @@ pub trait DeviceImpl {
///
/// If not `None`, the parent class's `realize` method is overridden
/// with the function pointed to by `REALIZE`.
- const REALIZE: Option<unsafe extern "C" fn(*mut DeviceState, *mut *mut Error)> = None;
+ const REALIZE: Option<fn(&mut Self)> = None;
/// If not `None`, the parent class's `reset` method is overridden
/// with the function pointed to by `RESET`.
///
/// Rust does not yet support the three-phase reset protocol; this is
/// usually okay for leaf classes.
- const RESET: Option<unsafe extern "C" fn(dev: *mut DeviceState)> = None;
+ const RESET: Option<fn(&mut Self)> = None;
/// An array providing the properties that the user can set on the
/// device. Not a `const` because referencing statics in constants
@@ -39,6 +40,30 @@ fn vmsd() -> Option<&'static VMStateDescription> {
}
}
+/// # Safety
+///
+/// This function is only called through the QOM machinery and
+/// the `impl_device_class!` macro.
+/// We expect the FFI user of this function to pass a valid pointer that
+/// can be downcasted to type `T`. We also expect the device is
+/// readable/writeable from one thread at any time.
+unsafe extern "C" fn rust_realize_fn<T: DeviceImpl>(dev: *mut DeviceState, _errp: *mut *mut Error) {
+ assert!(!dev.is_null());
+ let state = dev.cast::<T>();
+ T::REALIZE.unwrap()(unsafe { &mut *state });
+}
+
+/// # Safety
+///
+/// We expect the FFI user of this function to pass a valid pointer that
+/// can be downcasted to type `T`. We also expect the device is
+/// readable/writeable from one thread at any time.
+unsafe extern "C" fn rust_reset_fn<T: DeviceImpl>(dev: *mut DeviceState) {
+ assert!(!dev.is_null());
+ let state = dev.cast::<T>();
+ T::RESET.unwrap()(unsafe { &mut *state });
+}
+
/// # Safety
///
/// We expect the FFI user of this function to pass a valid pointer that
@@ -51,11 +80,11 @@ fn vmsd() -> Option<&'static VMStateDescription> {
let mut dc = ::core::ptr::NonNull::new(klass.cast::<DeviceClass>()).unwrap();
unsafe {
let dc = dc.as_mut();
- if let Some(realize_fn) = <T as DeviceImpl>::REALIZE {
- dc.realize = Some(realize_fn);
+ if <T as DeviceImpl>::REALIZE.is_some() {
+ dc.realize = Some(rust_realize_fn::<T>);
}
- if let Some(reset_fn) = <T as DeviceImpl>::RESET {
- bindings::device_class_set_legacy_reset(dc, Some(reset_fn));
+ if <T as DeviceImpl>::RESET.is_some() {
+ bindings::device_class_set_legacy_reset(dc, Some(rust_reset_fn::<T>));
}
if let Some(vmsd) = <T as DeviceImpl>::vmsd() {
dc.vmsd = vmsd;
Allow the DeviceImpl trait to expose safe Rust functions. rust_device_class_init<> adds thunks around the functions in DeviceImpl. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> --- rust/hw/char/pl011/src/device.rs | 5 ++-- rust/hw/char/pl011/src/device_class.rs | 26 ---------------- rust/qemu-api/src/definitions.rs | 2 +- rust/qemu-api/src/device_class.rs | 41 ++++++++++++++++++++++---- 4 files changed, 38 insertions(+), 36 deletions(-)