On Mon, Dec 09, 2024 at 01:37:05PM +0100, Paolo Bonzini wrote:
> Date: Mon, 9 Dec 2024 13:37:05 +0100
> From: Paolo Bonzini <pbonz...@redhat.com>
> Subject: [PATCH 14/26] rust: qom: move bridge for TypeInfo functions out of
> pl011
> X-Mailer: git-send-email 2.47.1
>
> Allow the ObjectImpl trait to expose Rust functions that avoid raw
> pointers (though INSTANCE_INIT for example is still unsafe).
> ObjectImpl::TYPE_INFO adds thunks around the functions in
> ObjectImpl.
>
> While at it, document `TypeInfo`.
>
> Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
> ---
> rust/hw/char/pl011/src/device.rs | 40 +++++++--------------
> rust/qemu-api/src/definitions.rs | 61 +++++++++++++++++++++++++++++---
> 2 files changed, 69 insertions(+), 32 deletions(-)
>
> diff --git a/rust/hw/char/pl011/src/device.rs
> b/rust/hw/char/pl011/src/device.rs
> index 56403c36609..b9f8fb134b5 100644
> --- a/rust/hw/char/pl011/src/device.rs
> +++ b/rust/hw/char/pl011/src/device.rs
> @@ -110,7 +110,7 @@ impl ObjectImpl for PL011State {
> type Class = PL011Class;
> 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);
> + const INSTANCE_INIT: Option<unsafe fn(&mut Self)> = Some(Self::init);
No need to keep `unsafe` here?
> +///
> +/// - the struct must be `#[repr(C)]`
> +///
> +/// - `Class` and `TYPE` must match the data in the `TypeInfo` (this is
> +/// automatic if the class is defined via `ObjectImpl`).
> +///
> +/// - the first field of the struct must be of the instance struct
> corresponding
> +/// to the superclass declared as `PARENT_TYPE_NAME`
> pub trait ObjectImpl: ClassInitImpl + Sized {
> + /// The QOM class object corresponding to this struct. Not used yet.
> type Class;
> +
> + /// The name of the type, which can be passed to `object_new()` to
> + /// generate an instance of this type.
> const TYPE_NAME: &'static CStr;
> +
> + /// The parent of the type. This should match the first field of
> + /// the struct that implements `ObjectImpl`:
> const PARENT_TYPE_NAME: Option<&'static CStr>;
> +
> + /// Whether the object can be instantiated
> 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;
> +
> + /// Function that is called to initialize an object. The parent class
> will
> + /// have already been initialized so the type is only responsible for
> + /// initializing its own members.
> + ///
> + /// FIXME: The argument is not really a valid reference. `&mut
> + /// MaybeUninit<Self>` would be a better description.
> + const INSTANCE_INIT: Option<unsafe fn(&mut Self)> = None;
And here.
> + /// Function that is called to finish initialization of an object, once
> + /// `INSTANCE_INIT` functions have been called.
> + const INSTANCE_POST_INIT: Option<fn(&mut Self)> = None;
>
Otherwise,
Reviewed-by: Zhao Liu <zhao1....@intel.com>
