From: Zhao Liu <zhao1....@intel.com> Add timer bindings to help handle idiomatic Rust callbacks.
Additionally, wrap QEMUClockType in ClockType binding to avoid unsafe calls in device code. Signed-off-by: Zhao Liu <zhao1....@intel.com> Link: https://lore.kernel.org/r/20250210030051.2562726-7-zhao1....@intel.com Signed-off-by: Paolo Bonzini <pbonz...@redhat.com> --- docs/devel/rust.rst | 1 + meson.build | 7 +++ rust/wrapper.h | 1 + rust/qemu-api/meson.build | 1 + rust/qemu-api/src/lib.rs | 1 + rust/qemu-api/src/timer.rs | 98 ++++++++++++++++++++++++++++++++++++++ 6 files changed, 109 insertions(+) create mode 100644 rust/qemu-api/src/timer.rs diff --git a/docs/devel/rust.rst b/docs/devel/rust.rst index a5399db50b5..90958e5a306 100644 --- a/docs/devel/rust.rst +++ b/docs/devel/rust.rst @@ -186,6 +186,7 @@ module status ``qdev`` stable ``qom`` stable ``sysbus`` stable +``timer`` stable ``vmstate`` proof of concept ``zeroable`` stable ================ ====================== diff --git a/meson.build b/meson.build index 16c76c493f3..8ed10b6624e 100644 --- a/meson.build +++ b/meson.build @@ -4087,6 +4087,13 @@ if have_rust foreach enum : c_bitfields bindgen_args += ['--bitfield-enum', enum] endforeach + c_nocopy = [ + 'QEMUTimer', + ] + # Used to customize Drop trait + foreach struct : c_nocopy + bindgen_args += ['--no-copy', struct] + endforeach # TODO: Remove this comment when the clang/libclang mismatch issue is solved. # diff --git a/rust/wrapper.h b/rust/wrapper.h index 54839ce0f51..a35bfbd1760 100644 --- a/rust/wrapper.h +++ b/rust/wrapper.h @@ -63,3 +63,4 @@ typedef enum memory_order { #include "migration/vmstate.h" #include "chardev/char-serial.h" #include "exec/memattrs.h" +#include "qemu/timer.h" diff --git a/rust/qemu-api/meson.build b/rust/qemu-api/meson.build index 45e30324b29..2e9c1078b9b 100644 --- a/rust/qemu-api/meson.build +++ b/rust/qemu-api/meson.build @@ -30,6 +30,7 @@ _qemu_api_rs = static_library( 'src/qdev.rs', 'src/qom.rs', 'src/sysbus.rs', + 'src/timer.rs', 'src/vmstate.rs', 'src/zeroable.rs', ], diff --git a/rust/qemu-api/src/lib.rs b/rust/qemu-api/src/lib.rs index 2a338a888a0..ed1a8f9a2b4 100644 --- a/rust/qemu-api/src/lib.rs +++ b/rust/qemu-api/src/lib.rs @@ -26,6 +26,7 @@ pub mod qdev; pub mod qom; pub mod sysbus; +pub mod timer; pub mod vmstate; pub mod zeroable; diff --git a/rust/qemu-api/src/timer.rs b/rust/qemu-api/src/timer.rs new file mode 100644 index 00000000000..a593538917a --- /dev/null +++ b/rust/qemu-api/src/timer.rs @@ -0,0 +1,98 @@ +// Copyright (C) 2024 Intel Corporation. +// Author(s): Zhao Liu <zhai1....@intel.com> +// SPDX-License-Identifier: GPL-2.0-or-later + +use std::os::raw::{c_int, c_void}; + +use crate::{ + bindings::{self, qemu_clock_get_ns, timer_del, timer_init_full, timer_mod, QEMUClockType}, + callbacks::FnCall, +}; + +pub type Timer = bindings::QEMUTimer; +pub type TimerListGroup = bindings::QEMUTimerListGroup; + +impl Timer { + pub const MS: u32 = bindings::SCALE_MS; + pub const US: u32 = bindings::SCALE_US; + pub const NS: u32 = bindings::SCALE_NS; + + pub fn new() -> Self { + Default::default() + } + + const fn as_mut_ptr(&self) -> *mut Self { + self as *const Timer as *mut _ + } + + pub fn init_full<'timer, 'opaque: 'timer, T, F>( + &'timer mut self, + timer_list_group: Option<&TimerListGroup>, + clk_type: ClockType, + scale: u32, + attributes: u32, + _cb: F, + opaque: &'opaque T, + ) where + F: for<'a> FnCall<(&'a T,)>, + { + let _: () = F::ASSERT_IS_SOME; + + /// timer expiration callback + unsafe extern "C" fn rust_timer_handler<T, F: for<'a> FnCall<(&'a T,)>>( + opaque: *mut c_void, + ) { + // SAFETY: the opaque was passed as a reference to `T`. + F::call((unsafe { &*(opaque.cast::<T>()) },)) + } + + let timer_cb: unsafe extern "C" fn(*mut c_void) = rust_timer_handler::<T, F>; + + // SAFETY: the opaque outlives the timer + unsafe { + timer_init_full( + self, + if let Some(g) = timer_list_group { + g as *const TimerListGroup as *mut _ + } else { + ::core::ptr::null_mut() + }, + clk_type.id, + scale as c_int, + attributes as c_int, + Some(timer_cb), + (opaque as *const T).cast::<c_void>() as *mut c_void, + ) + } + } + + pub fn modify(&self, expire_time: u64) { + unsafe { timer_mod(self.as_mut_ptr(), expire_time as i64) } + } + + pub fn delete(&self) { + unsafe { timer_del(self.as_mut_ptr()) } + } +} + +impl Drop for Timer { + fn drop(&mut self) { + self.delete() + } +} + +pub struct ClockType { + id: QEMUClockType, +} + +impl ClockType { + pub fn get_ns(&self) -> u64 { + // SAFETY: cannot be created outside this module, therefore id + // is valid + (unsafe { qemu_clock_get_ns(self.id) }) as u64 + } +} + +pub const CLOCK_VIRTUAL: ClockType = ClockType { + id: QEMUClockType::QEMU_CLOCK_VIRTUAL, +}; -- 2.48.1
