From: Paolo Bonzini Date: Fri, 17 Jan 2025 10:26:48 +0000 (+0100) Subject: rust: qdev: switch from legacy reset to Resettable X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=5472a38cb9e10bda897fc29d4841c00476f22585;p=qemu.git rust: qdev: switch from legacy reset to Resettable Reviewed-by: Zhao Liu Signed-off-by: Paolo Bonzini --- diff --git a/meson.build b/meson.build index 18cf9e2913..16c76c493f 100644 --- a/meson.build +++ b/meson.build @@ -4073,6 +4073,7 @@ if have_rust 'MigrationPriority', 'QEMUChrEvent', 'QEMUClockType', + 'ResetType', 'device_endian', 'module_init_type', ] diff --git a/rust/hw/char/pl011/src/device.rs b/rust/hw/char/pl011/src/device.rs index 37936a328b..1d0390b4fb 100644 --- a/rust/hw/char/pl011/src/device.rs +++ b/rust/hw/char/pl011/src/device.rs @@ -18,7 +18,7 @@ use qemu_api::{ c_str, impl_vmstate_forward, irq::InterruptSource, prelude::*, - qdev::{Clock, ClockEvent, DeviceImpl, DeviceState, Property}, + qdev::{Clock, ClockEvent, DeviceImpl, DeviceState, Property, ResetType, ResettablePhasesImpl}, qom::{ClassInitImpl, ObjectImpl, Owned, ParentField}, sysbus::{SysBusDevice, SysBusDeviceClass}, vmstate::VMStateDescription, @@ -171,7 +171,10 @@ impl DeviceImpl for PL011State { Some(&device_class::VMSTATE_PL011) } const REALIZE: Option = Some(Self::realize); - const RESET: Option = Some(Self::reset); +} + +impl ResettablePhasesImpl for PL011State { + const HOLD: Option = Some(Self::reset_hold); } impl PL011Registers { @@ -622,7 +625,7 @@ impl PL011State { } } - pub fn reset(&self) { + pub fn reset_hold(&self, _type: ResetType) { self.regs.borrow_mut().reset(); } @@ -737,3 +740,4 @@ impl ObjectImpl for PL011Luminary { } impl DeviceImpl for PL011Luminary {} +impl ResettablePhasesImpl for PL011Luminary {} diff --git a/rust/qemu-api/src/qdev.rs b/rust/qemu-api/src/qdev.rs index 34d24da4b6..64ba3d9098 100644 --- a/rust/qemu-api/src/qdev.rs +++ b/rust/qemu-api/src/qdev.rs @@ -10,10 +10,10 @@ use std::{ ptr::NonNull, }; -pub use bindings::{Clock, ClockEvent, DeviceClass, DeviceState, Property}; +pub use bindings::{Clock, ClockEvent, DeviceClass, DeviceState, Property, ResetType}; use crate::{ - bindings::{self, Error}, + bindings::{self, Error, ResettableClass}, callbacks::FnCall, cell::bql_locked, prelude::*, @@ -21,8 +21,70 @@ use crate::{ vmstate::VMStateDescription, }; +/// Trait providing the contents of the `ResettablePhases` struct, +/// which is part of the QOM `Resettable` interface. +pub trait ResettablePhasesImpl { + /// If not None, this is called when the object enters reset. It + /// can reset local state of the object, but it must not do anything that + /// has a side-effect on other objects, such as raising or lowering an + /// [`InterruptSource`](crate::irq::InterruptSource), or reading or + /// writing guest memory. It takes the reset's type as argument. + const ENTER: Option = None; + + /// If not None, this is called when the object for entry into reset, once + /// every object in the system which is being reset has had its + /// `ResettablePhasesImpl::ENTER` method called. At this point devices + /// can do actions that affect other objects. + /// + /// If in doubt, implement this method. + const HOLD: Option = None; + + /// If not None, this phase is called when the object leaves the reset + /// state. Actions affecting other objects are permitted. + const EXIT: Option = None; +} + +/// # 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_resettable_enter_fn( + obj: *mut Object, + typ: ResetType, +) { + let state = NonNull::new(obj).unwrap().cast::(); + T::ENTER.unwrap()(unsafe { state.as_ref() }, typ); +} + +/// # 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_resettable_hold_fn( + obj: *mut Object, + typ: ResetType, +) { + let state = NonNull::new(obj).unwrap().cast::(); + T::HOLD.unwrap()(unsafe { state.as_ref() }, typ); +} + +/// # 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_resettable_exit_fn( + obj: *mut Object, + typ: ResetType, +) { + let state = NonNull::new(obj).unwrap().cast::(); + T::EXIT.unwrap()(unsafe { state.as_ref() }, typ); +} + /// Trait providing the contents of [`DeviceClass`]. -pub trait DeviceImpl: ObjectImpl { +pub trait DeviceImpl: ObjectImpl + ResettablePhasesImpl { /// _Realization_ is the second stage of device creation. It contains /// all operations that depend on device properties and can fail (note: /// this is not yet supported for Rust devices). @@ -31,13 +93,6 @@ pub trait DeviceImpl: ObjectImpl { /// with the function pointed to by `REALIZE`. const REALIZE: Option = 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 = None; - /// An array providing the properties that the user can set on the /// device. Not a `const` because referencing statics in constants /// is unstable until Rust 1.83.0. @@ -65,29 +120,36 @@ unsafe extern "C" fn rust_realize_fn(dev: *mut DeviceState, _errp T::REALIZE.unwrap()(unsafe { state.as_ref() }); } -/// # 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(dev: *mut DeviceState) { - let mut state = NonNull::new(dev).unwrap().cast::(); - T::RESET.unwrap()(unsafe { state.as_mut() }); +unsafe impl InterfaceType for ResettableClass { + const TYPE_NAME: &'static CStr = + unsafe { CStr::from_bytes_with_nul_unchecked(bindings::TYPE_RESETTABLE_INTERFACE) }; +} + +impl ClassInitImpl for T +where + T: ResettablePhasesImpl, +{ + fn class_init(rc: &mut ResettableClass) { + if ::ENTER.is_some() { + rc.phases.enter = Some(rust_resettable_enter_fn::); + } + if ::HOLD.is_some() { + rc.phases.hold = Some(rust_resettable_hold_fn::); + } + if ::EXIT.is_some() { + rc.phases.exit = Some(rust_resettable_exit_fn::); + } + } } impl ClassInitImpl for T where - T: ClassInitImpl + DeviceImpl, + T: ClassInitImpl + ClassInitImpl + DeviceImpl, { fn class_init(dc: &mut DeviceClass) { if ::REALIZE.is_some() { dc.realize = Some(rust_realize_fn::); } - if ::RESET.is_some() { - unsafe { - bindings::device_class_set_legacy_reset(dc, Some(rust_reset_fn::)); - } - } if let Some(vmsd) = ::vmsd() { dc.vmsd = vmsd; } @@ -98,6 +160,7 @@ where } } + ResettableClass::interface_init::(dc); >::class_init(&mut dc.parent_class); } } diff --git a/rust/qemu-api/tests/tests.rs b/rust/qemu-api/tests/tests.rs index 10748fba19..92dbfb8a0c 100644 --- a/rust/qemu-api/tests/tests.rs +++ b/rust/qemu-api/tests/tests.rs @@ -13,7 +13,7 @@ use qemu_api::{ cell::{self, BqlCell}, declare_properties, define_property, prelude::*, - qdev::{DeviceClass, DeviceImpl, DeviceState, Property}, + qdev::{DeviceClass, DeviceImpl, DeviceState, Property, ResettablePhasesImpl}, qom::{ClassInitImpl, ObjectImpl, ParentField}, vmstate::VMStateDescription, zeroable::Zeroable, @@ -61,6 +61,8 @@ impl ObjectImpl for DummyState { const ABSTRACT: bool = false; } +impl ResettablePhasesImpl for DummyState {} + impl DeviceImpl for DummyState { fn properties() -> &'static [Property] { &DUMMY_PROPERTIES @@ -101,6 +103,7 @@ impl ObjectImpl for DummyChildState { const ABSTRACT: bool = false; } +impl ResettablePhasesImpl for DummyChildState {} impl DeviceImpl for DummyChildState {} impl ClassInitImpl for DummyChildState {