From: Marc-André Lureau Date: Mon, 8 Sep 2025 10:49:48 +0000 (+0200) Subject: rust: split Rust-only "common" crate X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=593c408a6a8cd8b0af9bf60c7c3625da7910a737;p=thirdparty%2Fqemu.git rust: split Rust-only "common" crate Signed-off-by: Marc-André Lureau Link: https://lore.kernel.org/r/20250827104147.717203-6-marcandre.lureau@redhat.com Reviewed-by: Zhao Liu Signed-off-by: Paolo Bonzini --- diff --git a/MAINTAINERS b/MAINTAINERS index fb045388b92..cee5a342062 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -3515,6 +3515,7 @@ F: include/hw/registerfields.h Rust M: Manos Pitsidianakis S: Maintained +F: rust/common/ F: rust/qemu-api F: rust/qemu-api-macros F: rust/rustfmt.toml diff --git a/rust/Cargo.lock b/rust/Cargo.lock index 4baf6ba663c..71e8c7ed62a 100644 --- a/rust/Cargo.lock +++ b/rust/Cargo.lock @@ -44,6 +44,13 @@ dependencies = [ "qemu_api_macros", ] +[[package]] +name = "common" +version = "0.1.0" +dependencies = [ + "libc", +] + [[package]] name = "either" version = "1.12.0" @@ -63,6 +70,7 @@ dependencies = [ name = "hpet" version = "0.1.0" dependencies = [ + "common", "qemu_api", "qemu_api_macros", ] @@ -89,6 +97,7 @@ dependencies = [ "bilge", "bilge-impl", "bits", + "common", "qemu_api", "qemu_api_macros", ] @@ -130,6 +139,7 @@ name = "qemu_api" version = "0.1.0" dependencies = [ "anyhow", + "common", "foreign", "libc", "qemu_api_macros", diff --git a/rust/Cargo.toml b/rust/Cargo.toml index cd4bf8ef8e1..c0426d42430 100644 --- a/rust/Cargo.toml +++ b/rust/Cargo.toml @@ -2,6 +2,7 @@ resolver = "2" members = [ "bits", + "common", "qemu-api-macros", "qemu-api", "hw/char/pl011", diff --git a/rust/common/Cargo.toml b/rust/common/Cargo.toml new file mode 100644 index 00000000000..5e106427e80 --- /dev/null +++ b/rust/common/Cargo.toml @@ -0,0 +1,19 @@ +[package] +name = "common" +version = "0.1.0" +description = "Rust common code for QEMU" +resolver = "2" +publish = false + +authors.workspace = true +edition.workspace = true +homepage.workspace = true +license.workspace = true +repository.workspace = true +rust-version.workspace = true + +[dependencies] +libc.workspace = true + +[lints] +workspace = true diff --git a/rust/common/meson.build b/rust/common/meson.build new file mode 100644 index 00000000000..230a967760d --- /dev/null +++ b/rust/common/meson.build @@ -0,0 +1,34 @@ +_common_cfg = run_command(rustc_args, + '--config-headers', config_host_h, '--features', files('Cargo.toml'), + capture: true, check: true).stdout().strip().splitlines() + +_common_rs = static_library( + 'common', + structured_sources( + [ + 'src/lib.rs', + 'src/assertions.rs', + 'src/bitops.rs', + 'src/callbacks.rs', + 'src/errno.rs', + 'src/opaque.rs', + 'src/uninit.rs', + 'src/zeroable.rs', + ], + ), + override_options: ['rust_std=2021', 'build.rust_std=2021'], + rust_abi: 'rust', + rust_args: _common_cfg, + dependencies: [libc_rs], +) + +common_rs = declare_dependency(link_with: [_common_rs]) + +# Doctests are essentially integration tests, so they need the same dependencies. +# Note that running them requires the object files for C code, so place them +# in a separate suite that is run by the "build" CI jobs rather than "check". +rust.doctest('rust-common-doctests', + _common_rs, + protocol: 'rust', + dependencies: common_rs, + suite: ['doc', 'rust']) diff --git a/rust/qemu-api/src/assertions.rs b/rust/common/src/assertions.rs similarity index 92% rename from rust/qemu-api/src/assertions.rs rename to rust/common/src/assertions.rs index e4fe23b674e..91f83a5d3d4 100644 --- a/rust/qemu-api/src/assertions.rs +++ b/rust/common/src/assertions.rs @@ -8,7 +8,7 @@ //! types match the expectations of C code. //! //! Documentation is hidden because it only exposes macros, which -//! are exported directly from `qemu_api`. +//! are exported directly from `common`. // Based on https://stackoverflow.com/questions/64251852/x/70978292#70978292 // (stackoverflow answers are released under MIT license). @@ -27,7 +27,7 @@ impl EqType for T { /// # Examples /// /// ``` -/// # use qemu_api::assert_same_type; +/// # use common::assert_same_type; /// # use std::ops::Deref; /// assert_same_type!(u32, u32); /// assert_same_type!( as Deref>::Target, u32); @@ -36,7 +36,7 @@ impl EqType for T { /// Different types will cause a compile failure /// /// ```compile_fail -/// # use qemu_api::assert_same_type; +/// # use common::assert_same_type; /// assert_same_type!(&Box, &u32); /// ``` #[macro_export] @@ -61,7 +61,7 @@ macro_rules! assert_same_type { /// # Examples /// /// ``` -/// # use qemu_api::assert_field_type; +/// # use common::assert_field_type; /// pub struct A { /// field1: u32, /// } @@ -72,7 +72,7 @@ macro_rules! assert_same_type { /// Different types will cause a compile failure /// /// ```compile_fail -/// # use qemu_api::assert_field_type; +/// # use common::assert_field_type; /// # pub struct A { field1: u32 } /// assert_field_type!(A, field1, i32); /// ``` @@ -103,7 +103,7 @@ macro_rules! assert_field_type { /// # Examples /// /// ``` -/// # use qemu_api::assert_match; +/// # use common::assert_match; /// // JoinHandle does not implement `Eq`, therefore the result /// // does not either. /// let result: Result, u32> = Err(42); @@ -132,12 +132,12 @@ macro_rules! assert_match { /// # Examples /// /// ``` -/// # use qemu_api::static_assert; +/// # use common::static_assert; /// static_assert!("abc".len() == 3); /// ``` /// /// ```compile_fail -/// # use qemu_api::static_assert; +/// # use common::static_assert; /// static_assert!("abc".len() == 2); // does not compile /// ``` #[macro_export] diff --git a/rust/qemu-api/src/bitops.rs b/rust/common/src/bitops.rs similarity index 98% rename from rust/qemu-api/src/bitops.rs rename to rust/common/src/bitops.rs index b1e3a530ab5..06c78c3b8a7 100644 --- a/rust/qemu-api/src/bitops.rs +++ b/rust/common/src/bitops.rs @@ -3,7 +3,6 @@ // SPDX-License-Identifier: GPL-2.0-or-later //! This module provides bit operation extensions to integer types. -//! It is usually included via the `qemu_api` prelude. use std::ops::{ Add, AddAssign, BitAnd, BitAndAssign, BitOr, BitOrAssign, BitXor, BitXorAssign, Div, DivAssign, diff --git a/rust/qemu-api/src/callbacks.rs b/rust/common/src/callbacks.rs similarity index 97% rename from rust/qemu-api/src/callbacks.rs rename to rust/common/src/callbacks.rs index dbe2305f509..b8898fe96f7 100644 --- a/rust/qemu-api/src/callbacks.rs +++ b/rust/common/src/callbacks.rs @@ -55,7 +55,7 @@ use std::{mem, ptr::NonNull}; /// # Examples /// /// ``` -/// # use qemu_api::callbacks::FnCall; +/// # use common::callbacks::FnCall; /// fn call_it FnCall<(&'a str,), String>>(_f: &F, s: &str) -> String { /// F::call((s,)) /// } @@ -71,7 +71,7 @@ use std::{mem, ptr::NonNull}; /// Attempting to pass a non-zero-sized closure causes a compile-time failure: /// /// ```compile_fail -/// # use qemu_api::callbacks::FnCall; +/// # use common::callbacks::FnCall; /// # fn call_it<'a, F: FnCall<(&'a str,), String>>(_f: &F, s: &'a str) -> String { /// # F::call((s,)) /// # } @@ -82,7 +82,7 @@ use std::{mem, ptr::NonNull}; /// `()` can be used to indicate "no function": /// /// ``` -/// # use qemu_api::callbacks::FnCall; +/// # use common::callbacks::FnCall; /// fn optional FnCall<(&'a str,), String>>(_f: &F, s: &str) -> Option { /// if F::IS_SOME { /// Some(F::call((s,))) @@ -97,7 +97,7 @@ use std::{mem, ptr::NonNull}; /// Invoking `F::call` will then be a run-time error. /// /// ```should_panic -/// # use qemu_api::callbacks::FnCall; +/// # use common::callbacks::FnCall; /// # fn call_it FnCall<(&'a str,), String>>(_f: &F, s: &str) -> String { /// # F::call((s,)) /// # } @@ -120,7 +120,7 @@ pub unsafe trait FnCall: 'static + Sync + Sized { /// You can use `IS_SOME` to catch this at compile time: /// /// ```compile_fail - /// # use qemu_api::callbacks::FnCall; + /// # use common::callbacks::FnCall; /// fn call_it FnCall<(&'a str,), String>>(_f: &F, s: &str) -> String { /// const { assert!(F::IS_SOME) } /// F::call((s,)) diff --git a/rust/qemu-api/src/errno.rs b/rust/common/src/errno.rs similarity index 98% rename from rust/qemu-api/src/errno.rs rename to rust/common/src/errno.rs index 507850fe33c..64b2933b078 100644 --- a/rust/qemu-api/src/errno.rs +++ b/rust/common/src/errno.rs @@ -185,7 +185,7 @@ use traits::{GetErrno, MergeErrno}; /// are interpreted as negated `errno` and turned into an `Err`. /// /// ``` -/// # use qemu_api::errno::into_io_result; +/// # use common::errno::into_io_result; /// # use std::io::ErrorKind; /// let ok = into_io_result(1i32).unwrap(); /// assert_eq!(ok, 1u32); @@ -201,7 +201,7 @@ use traits::{GetErrno, MergeErrno}; /// likely overflows and will panic: /// /// ```should_panic -/// # use qemu_api::errno::into_io_result; +/// # use common::errno::into_io_result; /// # #[allow(dead_code)] /// let err = into_io_result(-0x1234_5678i32); // panic /// ``` @@ -213,7 +213,7 @@ pub fn into_io_result(value: T) -> io::Result { /// values to report errors. /// /// ``` -/// # use qemu_api::errno::into_neg_errno; +/// # use common::errno::into_neg_errno; /// # use std::io::{self, ErrorKind}; /// let ok: io::Result<()> = Ok(()); /// assert_eq!(into_neg_errno(ok), 0); @@ -232,7 +232,7 @@ pub fn into_io_result(value: T) -> io::Result { /// positive: /// /// ```should_panic -/// # use qemu_api::errno::into_neg_errno; +/// # use common::errno::into_neg_errno; /// # use std::io; /// let err: io::Result = Ok(0x8899_AABB); /// into_neg_errno(err) // panic diff --git a/rust/common/src/lib.rs b/rust/common/src/lib.rs new file mode 100644 index 00000000000..25216503aab --- /dev/null +++ b/rust/common/src/lib.rs @@ -0,0 +1,20 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +pub mod assertions; + +pub mod bitops; + +pub mod callbacks; +pub use callbacks::FnCall; + +pub mod errno; +pub use errno::Errno; + +pub mod opaque; +pub use opaque::{Opaque, Wrapper}; + +pub mod uninit; +pub use uninit::MaybeUninitField; + +pub mod zeroable; +pub use zeroable::Zeroable; diff --git a/rust/common/src/opaque.rs b/rust/common/src/opaque.rs new file mode 100644 index 00000000000..d25a5f3ae1a --- /dev/null +++ b/rust/common/src/opaque.rs @@ -0,0 +1,238 @@ +// SPDX-License-Identifier: MIT + +//! ## Opaque wrappers +//! +//! The cell types from the previous section are useful at the boundaries +//! of code that requires interior mutability. When writing glue code that +//! interacts directly with C structs, however, it is useful to operate +//! at a lower level. +//! +//! C functions often violate Rust's fundamental assumptions about memory +//! safety by modifying memory even if it is shared. Furthermore, C structs +//! often start their life uninitialized and may be populated lazily. +//! +//! For this reason, this module provides the [`Opaque`] type to opt out +//! of Rust's usual guarantees about the wrapped type. Access to the wrapped +//! value is always through raw pointers, obtained via methods like +//! [`as_mut_ptr()`](Opaque::as_mut_ptr) and [`as_ptr()`](Opaque::as_ptr). These +//! pointers can then be passed to C functions or dereferenced; both actions +//! require `unsafe` blocks, making it clear where safety guarantees must be +//! manually verified. For example +//! +//! ```ignore +//! unsafe { +//! let state = Opaque::::uninit(); +//! qemu_struct_init(state.as_mut_ptr()); +//! } +//! ``` +//! +//! [`Opaque`] will usually be wrapped one level further, so that +//! bridge methods can be added to the wrapper: +//! +//! ```ignore +//! pub struct MyStruct(Opaque); +//! +//! impl MyStruct { +//! fn new() -> Pin> { +//! let result = Box::pin(unsafe { Opaque::uninit() }); +//! unsafe { qemu_struct_init(result.as_mut_ptr()) }; +//! result +//! } +//! } +//! ``` +//! +//! This pattern of wrapping bindgen-generated types in [`Opaque`] provides +//! several advantages: +//! +//! * The choice of traits to be implemented is not limited by the +//! bindgen-generated code. For example, [`Drop`] can be added without +//! disabling [`Copy`] on the underlying bindgen type +//! +//! * [`Send`] and [`Sync`] implementations can be controlled by the wrapper +//! type rather than being automatically derived from the C struct's layout +//! +//! * Methods can be implemented in a separate crate from the bindgen-generated +//! bindings +//! +//! * [`Debug`](std::fmt::Debug) and [`Display`](std::fmt::Display) +//! implementations can be customized to be more readable than the raw C +//! struct representation +//! +//! The [`Opaque`] type does not include BQL validation; it is possible to +//! assert in the code that the right lock is taken, to use it together +//! with a custom lock guard type, or to let C code take the lock, as +//! appropriate. It is also possible to use it with non-thread-safe +//! types, since by default (unlike [`BqlCell`] and [`BqlRefCell`] +//! it is neither `Sync` nor `Send`. +//! +//! While [`Opaque`] is necessary for C interop, it should be used sparingly +//! and only at FFI boundaries. For QEMU-specific types that need interior +//! mutability, prefer [`BqlCell`] or [`BqlRefCell`]. +//! +//! [`BqlCell`]: ../../qemu_api/cell/struct.BqlCell.html +//! [`BqlRefCell`]: ../../qemu_api/cell/struct.BqlRefCell.html +use std::{cell::UnsafeCell, fmt, marker::PhantomPinned, mem::MaybeUninit, ptr::NonNull}; + +/// Stores an opaque value that is shared with C code. +/// +/// Often, C structs can changed when calling a C function even if they are +/// behind a shared Rust reference, or they can be initialized lazily and have +/// invalid bit patterns (e.g. `3` for a [`bool`]). This goes against Rust's +/// strict aliasing rules, which normally prevent mutation through shared +/// references. +/// +/// Wrapping the struct with `Opaque` ensures that the Rust compiler does not +/// assume the usual constraints that Rust structs require, and allows using +/// shared references on the Rust side. +/// +/// `Opaque` is `#[repr(transparent)]`, so that it matches the memory layout +/// of `T`. +#[repr(transparent)] +pub struct Opaque { + value: UnsafeCell>, + // PhantomPinned also allows multiple references to the `Opaque`, i.e. + // one `&mut Opaque` can coexist with a `&mut T` or any number of `&T`; + // see https://docs.rs/pinned-aliasable/latest/pinned_aliasable/. + _pin: PhantomPinned, +} + +impl Opaque { + /// Creates a new shared reference from a C pointer + /// + /// # Safety + /// + /// The pointer must be valid, though it need not point to a valid value. + pub unsafe fn from_raw<'a>(ptr: *mut T) -> &'a Self { + let ptr = NonNull::new(ptr).unwrap().cast::(); + // SAFETY: Self is a transparent wrapper over T + unsafe { ptr.as_ref() } + } + + /// Creates a new opaque object with uninitialized contents. + /// + /// # Safety + /// + /// Ultimately the pointer to the returned value will be dereferenced + /// in another `unsafe` block, for example when passing it to a C function, + /// but the functions containing the dereference are usually safe. The + /// value returned from `uninit()` must be initialized and pinned before + /// calling them. + pub const unsafe fn uninit() -> Self { + Self { + value: UnsafeCell::new(MaybeUninit::uninit()), + _pin: PhantomPinned, + } + } + + /// Creates a new opaque object with zeroed contents. + /// + /// # Safety + /// + /// Ultimately the pointer to the returned value will be dereferenced + /// in another `unsafe` block, for example when passing it to a C function, + /// but the functions containing the dereference are usually safe. The + /// value returned from `uninit()` must be pinned (and possibly initialized) + /// before calling them. + pub const unsafe fn zeroed() -> Self { + Self { + value: UnsafeCell::new(MaybeUninit::zeroed()), + _pin: PhantomPinned, + } + } + + /// Returns a raw mutable pointer to the opaque data. + pub const fn as_mut_ptr(&self) -> *mut T { + UnsafeCell::get(&self.value).cast() + } + + /// Returns a raw pointer to the opaque data. + pub const fn as_ptr(&self) -> *const T { + self.as_mut_ptr().cast_const() + } + + /// Returns a raw pointer to the opaque data that can be passed to a + /// C function as `void *`. + pub const fn as_void_ptr(&self) -> *mut std::ffi::c_void { + UnsafeCell::get(&self.value).cast() + } + + /// Converts a raw pointer to the wrapped type. + pub const fn raw_get(slot: *mut Self) -> *mut T { + // Compare with Linux's raw_get method, which goes through an UnsafeCell + // because it takes a *const Self instead. + slot.cast() + } +} + +impl fmt::Debug for Opaque { + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + let mut name: String = "Opaque<".to_string(); + name += std::any::type_name::(); + name += ">"; + f.debug_tuple(&name).field(&self.as_ptr()).finish() + } +} + +impl Opaque { + /// Creates a new opaque object with default contents. + /// + /// # Safety + /// + /// Ultimately the pointer to the returned value will be dereferenced + /// in another `unsafe` block, for example when passing it to a C function, + /// but the functions containing the dereference are usually safe. The + /// value returned from `uninit()` must be pinned before calling them. + pub unsafe fn new() -> Self { + Self { + value: UnsafeCell::new(MaybeUninit::new(T::default())), + _pin: PhantomPinned, + } + } +} + +/// Annotates [`Self`] as a transparent wrapper for another type. +/// +/// Usually defined via the [`qemu_api_macros::Wrapper`] derive macro. +/// +/// # Examples +/// +/// ``` +/// # use std::mem::ManuallyDrop; +/// # use common::opaque::Wrapper; +/// #[repr(transparent)] +/// pub struct Example { +/// inner: ManuallyDrop, +/// } +/// +/// unsafe impl Wrapper for Example { +/// type Wrapped = String; +/// } +/// ``` +/// +/// # Safety +/// +/// `Self` must be a `#[repr(transparent)]` wrapper for the `Wrapped` type, +/// whether directly or indirectly. +/// +/// # Methods +/// +/// By convention, types that implement Wrapper also implement the following +/// methods: +/// +/// ```ignore +/// pub const unsafe fn from_raw<'a>(value: *mut Self::Wrapped) -> &'a Self; +/// pub const unsafe fn as_mut_ptr(&self) -> *mut Self::Wrapped; +/// pub const unsafe fn as_ptr(&self) -> *const Self::Wrapped; +/// pub const unsafe fn raw_get(slot: *mut Self) -> *const Self::Wrapped; +/// ``` +/// +/// They are not defined here to allow them to be `const`. +/// +/// [`qemu_api_macros::Wrapper`]: ../../qemu_api_macros/derive.Wrapper.html +pub unsafe trait Wrapper { + type Wrapped; +} + +unsafe impl Wrapper for Opaque { + type Wrapped = T; +} diff --git a/rust/qemu-api/src/uninit.rs b/rust/common/src/uninit.rs similarity index 98% rename from rust/qemu-api/src/uninit.rs rename to rust/common/src/uninit.rs index b0a829729dd..e7f9fcd2e3f 100644 --- a/rust/qemu-api/src/uninit.rs +++ b/rust/common/src/uninit.rs @@ -63,7 +63,7 @@ impl<'a, T, U> DerefMut for MaybeUninitField<'a, T, U> { /// } /// /// # use std::mem::MaybeUninit; -/// # use qemu_api::{assert_match, uninit_field_mut}; +/// # use common::{assert_match, uninit_field_mut}; /// /// let mut s: MaybeUninit = MaybeUninit::zeroed(); /// uninit_field_mut!(s, x).write(5); diff --git a/rust/common/src/zeroable.rs b/rust/common/src/zeroable.rs new file mode 100644 index 00000000000..fd056deb1f6 --- /dev/null +++ b/rust/common/src/zeroable.rs @@ -0,0 +1,18 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +//! Defines a trait for structs that can be safely initialized with zero bytes. + +/// Encapsulates the requirement that +/// `MaybeUninit::::zeroed().assume_init()` does not cause undefined +/// behavior. +/// +/// # Safety +/// +/// Do not add this trait to a type unless all-zeroes is a valid value for the +/// type. In particular, raw pointers can be zero, but references and +/// `NonNull` cannot. +pub unsafe trait Zeroable: Default { + /// Return a value of Self whose memory representation consists of all + /// zeroes, with the possible exclusion of padding bytes. + const ZERO: Self = unsafe { ::core::mem::MaybeUninit::::zeroed().assume_init() }; +} diff --git a/rust/hw/char/pl011/Cargo.toml b/rust/hw/char/pl011/Cargo.toml index 88ef110507d..6d15f107dfa 100644 --- a/rust/hw/char/pl011/Cargo.toml +++ b/rust/hw/char/pl011/Cargo.toml @@ -16,6 +16,7 @@ rust-version.workspace = true bilge = { version = "0.2.0" } bilge-impl = { version = "0.2.0" } bits = { path = "../../../bits" } +common = { path = "../../../common" } qemu_api = { path = "../../../qemu-api" } qemu_api_macros = { path = "../../../qemu-api-macros" } diff --git a/rust/hw/char/pl011/meson.build b/rust/hw/char/pl011/meson.build index 2a1be329abc..c4a9f531f7d 100644 --- a/rust/hw/char/pl011/meson.build +++ b/rust/hw/char/pl011/meson.build @@ -7,7 +7,8 @@ _libpl011_rs = static_library( bilge_rs, bilge_impl_rs, bits_rs, - qemu_api, + common_rs, + qemu_api_rs, qemu_api_macros, ], ) diff --git a/rust/hw/char/pl011/src/device.rs b/rust/hw/char/pl011/src/device.rs index 8411db8d00c..b4aa6c45f87 100644 --- a/rust/hw/char/pl011/src/device.rs +++ b/rust/hw/char/pl011/src/device.rs @@ -4,6 +4,7 @@ use std::{ffi::CStr, mem::size_of}; +use common::{static_assert, uninit_field_mut}; use qemu_api::{ chardev::{CharBackend, Chardev, Event}, impl_vmstate_forward, impl_vmstate_struct, @@ -14,9 +15,7 @@ use qemu_api::{ prelude::*, qdev::{Clock, ClockEvent, DeviceImpl, DeviceState, ResetType, ResettablePhasesImpl}, qom::{ObjectImpl, Owned, ParentField, ParentInit}, - static_assert, sysbus::{SysBusDevice, SysBusDeviceImpl}, - uninit_field_mut, vmstate::{self, VMStateDescription, VMStateDescriptionBuilder}, vmstate_fields, vmstate_of, vmstate_subsections, vmstate_unused, }; diff --git a/rust/hw/timer/hpet/Cargo.toml b/rust/hw/timer/hpet/Cargo.toml index ac5df23c1d0..ba7354f07e0 100644 --- a/rust/hw/timer/hpet/Cargo.toml +++ b/rust/hw/timer/hpet/Cargo.toml @@ -11,6 +11,7 @@ repository.workspace = true rust-version.workspace = true [dependencies] +common = { path = "../../../common" } qemu_api = { path = "../../../qemu-api" } qemu_api_macros = { path = "../../../qemu-api-macros" } diff --git a/rust/hw/timer/hpet/meson.build b/rust/hw/timer/hpet/meson.build index c2d7c0532ca..c91d330439a 100644 --- a/rust/hw/timer/hpet/meson.build +++ b/rust/hw/timer/hpet/meson.build @@ -4,7 +4,8 @@ _libhpet_rs = static_library( override_options: ['rust_std=2021', 'build.rust_std=2021'], rust_abi: 'rust', dependencies: [ - qemu_api, + common_rs, + qemu_api_rs, qemu_api_macros, ], ) diff --git a/rust/hw/timer/hpet/src/device.rs b/rust/hw/timer/hpet/src/device.rs index dd5326a40d4..72375d31550 100644 --- a/rust/hw/timer/hpet/src/device.rs +++ b/rust/hw/timer/hpet/src/device.rs @@ -10,6 +10,7 @@ use std::{ slice::from_ref, }; +use common::{bitops::IntegerExt, uninit_field_mut}; use qemu_api::{ bindings::{ address_space_memory, address_space_stl_le, qdev_prop_bit, qdev_prop_bool, @@ -27,7 +28,6 @@ use qemu_api::{ qom_isa, sysbus::{SysBusDevice, SysBusDeviceImpl}, timer::{Timer, CLOCK_VIRTUAL, NANOSECONDS_PER_SECOND}, - uninit_field_mut, vmstate::{self, VMStateDescription, VMStateDescriptionBuilder}, vmstate_fields, vmstate_of, vmstate_subsections, vmstate_validate, }; diff --git a/rust/hw/timer/hpet/src/fw_cfg.rs b/rust/hw/timer/hpet/src/fw_cfg.rs index 619d662ee1e..0605225fbb1 100644 --- a/rust/hw/timer/hpet/src/fw_cfg.rs +++ b/rust/hw/timer/hpet/src/fw_cfg.rs @@ -4,7 +4,8 @@ use std::ptr::addr_of_mut; -use qemu_api::{cell::bql_locked, zeroable::Zeroable}; +use common::Zeroable; +use qemu_api::cell::bql_locked; /// Each `HPETState` represents a Event Timer Block. The v1 spec supports /// up to 8 blocks. QEMU only uses 1 block (in PC machine). diff --git a/rust/meson.build b/rust/meson.build index 331f11b7e72..402f8d66007 100644 --- a/rust/meson.build +++ b/rust/meson.build @@ -22,6 +22,7 @@ qemuutil_rs = qemuutil.partial_dependency(link_args: true, links: true) genrs = [] +subdir('common') subdir('qemu-api-macros') subdir('bits') subdir('qemu-api') diff --git a/rust/qemu-api-macros/src/lib.rs b/rust/qemu-api-macros/src/lib.rs index a65a7ce2fe9..49003a47801 100644 --- a/rust/qemu-api-macros/src/lib.rs +++ b/rust/qemu-api-macros/src/lib.rs @@ -97,7 +97,7 @@ fn derive_object_or_error(input: DeriveInput) -> Result::ParentType>); ::qemu_api::module_init! { @@ -125,20 +125,20 @@ fn derive_opaque_or_error(input: DeriveInput) -> Result::Wrapped; + unsafe impl ::common::opaque::Wrapper for #name { + type Wrapped = <#typ as ::common::opaque::Wrapper>::Wrapped; } impl #name { - pub unsafe fn from_raw<'a>(ptr: *mut ::Wrapped) -> &'a Self { + pub unsafe fn from_raw<'a>(ptr: *mut ::Wrapped) -> &'a Self { let ptr = ::std::ptr::NonNull::new(ptr).unwrap().cast::(); unsafe { ptr.as_ref() } } - pub const fn as_mut_ptr(&self) -> *mut ::Wrapped { + pub const fn as_mut_ptr(&self) -> *mut ::Wrapped { self.0.as_mut_ptr() } - pub const fn as_ptr(&self) -> *const ::Wrapped { + pub const fn as_ptr(&self) -> *const ::Wrapped { self.0.as_ptr() } @@ -146,7 +146,7 @@ fn derive_opaque_or_error(input: DeriveInput) -> Result *mut ::Wrapped { + pub const fn raw_get(slot: *mut Self) -> *mut ::Wrapped { slot.cast() } } @@ -282,7 +282,7 @@ fn derive_device_or_error(input: DeriveInput) -> Result::ParentType> diff --git a/rust/qemu-api/Cargo.toml b/rust/qemu-api/Cargo.toml index c5ed78035b6..2e0e2044912 100644 --- a/rust/qemu-api/Cargo.toml +++ b/rust/qemu-api/Cargo.toml @@ -14,6 +14,7 @@ repository.workspace = true rust-version.workspace = true [dependencies] +common = { path = "../common" } qemu_api_macros = { path = "../qemu-api-macros" } anyhow = { workspace = true } foreign = { workspace = true } diff --git a/rust/qemu-api/meson.build b/rust/qemu-api/meson.build index 062009f1618..64af3caef58 100644 --- a/rust/qemu-api/meson.build +++ b/rust/qemu-api/meson.build @@ -52,13 +52,9 @@ _qemu_api_rs = static_library( structured_sources( [ 'src/lib.rs', - 'src/assertions.rs', 'src/bindings.rs', - 'src/bitops.rs', - 'src/callbacks.rs', 'src/cell.rs', 'src/chardev.rs', - 'src/errno.rs', 'src/error.rs', 'src/irq.rs', 'src/log.rs', @@ -69,23 +65,21 @@ _qemu_api_rs = static_library( 'src/qom.rs', 'src/sysbus.rs', 'src/timer.rs', - 'src/uninit.rs', 'src/vmstate.rs', - 'src/zeroable.rs', ], {'.' : _qemu_api_bindings_inc_rs}, ), override_options: ['rust_std=2021', 'build.rust_std=2021'], rust_abi: 'rust', rust_args: _qemu_api_cfg, - dependencies: [anyhow_rs, foreign_rs, libc_rs, qemu_api_macros, qemuutil_rs, + dependencies: [anyhow_rs, common_rs, foreign_rs, libc_rs, qemu_api_macros, qemuutil_rs, qom, hwcore, chardev, migration], ) rust.test('rust-qemu-api-tests', _qemu_api_rs, suite: ['unit', 'rust']) -qemu_api = declare_dependency(link_with: [_qemu_api_rs], +qemu_api_rs = declare_dependency(link_with: [_qemu_api_rs], dependencies: [qemu_api_macros, qom, hwcore, chardev, migration]) # Doctests are essentially integration tests, so they need the same dependencies. @@ -94,7 +88,7 @@ qemu_api = declare_dependency(link_with: [_qemu_api_rs], rust.doctest('rust-qemu-api-doctests', _qemu_api_rs, protocol: 'rust', - dependencies: qemu_api, + dependencies: [qemu_api_rs], suite: ['doc', 'rust']) test('rust-qemu-api-integration', @@ -104,7 +98,7 @@ test('rust-qemu-api-integration', override_options: ['rust_std=2021', 'build.rust_std=2021'], rust_args: ['--test'], install: false, - dependencies: [qemu_api]), + dependencies: [common_rs, qemu_api_rs]), args: [ '--test', '--test-threads', '1', '--format', 'pretty', diff --git a/rust/qemu-api/src/bindings.rs b/rust/qemu-api/src/bindings.rs index b8104dea8be..3acdd903b52 100644 --- a/rust/qemu-api/src/bindings.rs +++ b/rust/qemu-api/src/bindings.rs @@ -20,6 +20,8 @@ //! `bindgen`-generated declarations. +use common::Zeroable; + #[cfg(MESON)] include!("bindings.inc.rs"); @@ -56,3 +58,22 @@ unsafe impl Sync for VMStateField {} unsafe impl Send for VMStateInfo {} unsafe impl Sync for VMStateInfo {} + +// bindgen does not derive Default here +#[allow(clippy::derivable_impls)] +impl Default for crate::bindings::VMStateFlags { + fn default() -> Self { + Self(0) + } +} + +unsafe impl Zeroable for crate::bindings::Property__bindgen_ty_1 {} +unsafe impl Zeroable for crate::bindings::Property {} +unsafe impl Zeroable for crate::bindings::VMStateFlags {} +unsafe impl Zeroable for crate::bindings::VMStateField {} +unsafe impl Zeroable for crate::bindings::VMStateDescription {} +unsafe impl Zeroable for crate::bindings::MemoryRegionOps__bindgen_ty_1 {} +unsafe impl Zeroable for crate::bindings::MemoryRegionOps__bindgen_ty_2 {} +unsafe impl Zeroable for crate::bindings::MemoryRegionOps {} +unsafe impl Zeroable for crate::bindings::MemTxAttrs {} +unsafe impl Zeroable for crate::bindings::CharBackend {} diff --git a/rust/qemu-api/src/cell.rs b/rust/qemu-api/src/cell.rs index 9943d7286b6..d13848df200 100644 --- a/rust/qemu-api/src/cell.rs +++ b/rust/qemu-api/src/cell.rs @@ -141,82 +141,13 @@ //! Multiple immutable borrows are allowed via [`borrow`](BqlRefCell::borrow), //! or a single mutable borrow via [`borrow_mut`](BqlRefCell::borrow_mut). The //! thread will panic if these rules are violated or if the BQL is not held. -//! -//! ## Opaque wrappers -//! -//! The cell types from the previous section are useful at the boundaries -//! of code that requires interior mutability. When writing glue code that -//! interacts directly with C structs, however, it is useful to operate -//! at a lower level. -//! -//! C functions often violate Rust's fundamental assumptions about memory -//! safety by modifying memory even if it is shared. Furthermore, C structs -//! often start their life uninitialized and may be populated lazily. -//! -//! For this reason, this module provides the [`Opaque`] type to opt out -//! of Rust's usual guarantees about the wrapped type. Access to the wrapped -//! value is always through raw pointers, obtained via methods like -//! [`as_mut_ptr()`](Opaque::as_mut_ptr) and [`as_ptr()`](Opaque::as_ptr). These -//! pointers can then be passed to C functions or dereferenced; both actions -//! require `unsafe` blocks, making it clear where safety guarantees must be -//! manually verified. For example -//! -//! ```ignore -//! unsafe { -//! let state = Opaque::::uninit(); -//! qemu_struct_init(state.as_mut_ptr()); -//! } -//! ``` -//! -//! [`Opaque`] will usually be wrapped one level further, so that -//! bridge methods can be added to the wrapper: -//! -//! ```ignore -//! pub struct MyStruct(Opaque); -//! -//! impl MyStruct { -//! fn new() -> Pin> { -//! let result = Box::pin(unsafe { Opaque::uninit() }); -//! unsafe { qemu_struct_init(result.as_mut_ptr()) }; -//! result -//! } -//! } -//! ``` -//! -//! This pattern of wrapping bindgen-generated types in [`Opaque`] provides -//! several advantages: -//! -//! * The choice of traits to be implemented is not limited by the -//! bindgen-generated code. For example, [`Drop`] can be added without -//! disabling [`Copy`] on the underlying bindgen type -//! -//! * [`Send`] and [`Sync`] implementations can be controlled by the wrapper -//! type rather than being automatically derived from the C struct's layout -//! -//! * Methods can be implemented in a separate crate from the bindgen-generated -//! bindings -//! -//! * [`Debug`](std::fmt::Debug) and [`Display`](std::fmt::Display) -//! implementations can be customized to be more readable than the raw C -//! struct representation -//! -//! The [`Opaque`] type does not include BQL validation; it is possible to -//! assert in the code that the right lock is taken, to use it together -//! with a custom lock guard type, or to let C code take the lock, as -//! appropriate. It is also possible to use it with non-thread-safe -//! types, since by default (unlike [`BqlCell`] and [`BqlRefCell`] -//! it is neither `Sync` nor `Send`. -//! -//! While [`Opaque`] is necessary for C interop, it should be used sparingly -//! and only at FFI boundaries. For QEMU-specific types that need interior -//! mutability, prefer [`BqlCell`] or [`BqlRefCell`]. use std::{ cell::{Cell, UnsafeCell}, cmp::Ordering, fmt, - marker::{PhantomData, PhantomPinned}, - mem::{self, MaybeUninit}, + marker::PhantomData, + mem, ops::{Deref, DerefMut}, ptr::NonNull, }; @@ -939,165 +870,3 @@ impl fmt::Display for BqlRefMut<'_, T> { (**self).fmt(f) } } - -/// Stores an opaque value that is shared with C code. -/// -/// Often, C structs can changed when calling a C function even if they are -/// behind a shared Rust reference, or they can be initialized lazily and have -/// invalid bit patterns (e.g. `3` for a [`bool`]). This goes against Rust's -/// strict aliasing rules, which normally prevent mutation through shared -/// references. -/// -/// Wrapping the struct with `Opaque` ensures that the Rust compiler does not -/// assume the usual constraints that Rust structs require, and allows using -/// shared references on the Rust side. -/// -/// `Opaque` is `#[repr(transparent)]`, so that it matches the memory layout -/// of `T`. -#[repr(transparent)] -pub struct Opaque { - value: UnsafeCell>, - // PhantomPinned also allows multiple references to the `Opaque`, i.e. - // one `&mut Opaque` can coexist with a `&mut T` or any number of `&T`; - // see https://docs.rs/pinned-aliasable/latest/pinned_aliasable/. - _pin: PhantomPinned, -} - -impl Opaque { - /// Creates a new shared reference from a C pointer - /// - /// # Safety - /// - /// The pointer must be valid, though it need not point to a valid value. - pub unsafe fn from_raw<'a>(ptr: *mut T) -> &'a Self { - let ptr = NonNull::new(ptr).unwrap().cast::(); - // SAFETY: Self is a transparent wrapper over T - unsafe { ptr.as_ref() } - } - - /// Creates a new opaque object with uninitialized contents. - /// - /// # Safety - /// - /// Ultimately the pointer to the returned value will be dereferenced - /// in another `unsafe` block, for example when passing it to a C function, - /// but the functions containing the dereference are usually safe. The - /// value returned from `uninit()` must be initialized and pinned before - /// calling them. - pub const unsafe fn uninit() -> Self { - Self { - value: UnsafeCell::new(MaybeUninit::uninit()), - _pin: PhantomPinned, - } - } - - /// Creates a new opaque object with zeroed contents. - /// - /// # Safety - /// - /// Ultimately the pointer to the returned value will be dereferenced - /// in another `unsafe` block, for example when passing it to a C function, - /// but the functions containing the dereference are usually safe. The - /// value returned from `uninit()` must be pinned (and possibly initialized) - /// before calling them. - pub const unsafe fn zeroed() -> Self { - Self { - value: UnsafeCell::new(MaybeUninit::zeroed()), - _pin: PhantomPinned, - } - } - - /// Returns a raw mutable pointer to the opaque data. - pub const fn as_mut_ptr(&self) -> *mut T { - UnsafeCell::get(&self.value).cast() - } - - /// Returns a raw pointer to the opaque data. - pub const fn as_ptr(&self) -> *const T { - self.as_mut_ptr().cast_const() - } - - /// Returns a raw pointer to the opaque data that can be passed to a - /// C function as `void *`. - pub const fn as_void_ptr(&self) -> *mut std::ffi::c_void { - UnsafeCell::get(&self.value).cast() - } - - /// Converts a raw pointer to the wrapped type. - pub const fn raw_get(slot: *mut Self) -> *mut T { - // Compare with Linux's raw_get method, which goes through an UnsafeCell - // because it takes a *const Self instead. - slot.cast() - } -} - -impl fmt::Debug for Opaque { - fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { - let mut name: String = "Opaque<".to_string(); - name += std::any::type_name::(); - name += ">"; - f.debug_tuple(&name).field(&self.as_ptr()).finish() - } -} - -impl Opaque { - /// Creates a new opaque object with default contents. - /// - /// # Safety - /// - /// Ultimately the pointer to the returned value will be dereferenced - /// in another `unsafe` block, for example when passing it to a C function, - /// but the functions containing the dereference are usually safe. The - /// value returned from `uninit()` must be pinned before calling them. - pub unsafe fn new() -> Self { - Self { - value: UnsafeCell::new(MaybeUninit::new(T::default())), - _pin: PhantomPinned, - } - } -} - -/// Annotates [`Self`] as a transparent wrapper for another type. -/// -/// Usually defined via the [`qemu_api_macros::Wrapper`] derive macro. -/// -/// # Examples -/// -/// ``` -/// # use std::mem::ManuallyDrop; -/// # use qemu_api::cell::Wrapper; -/// #[repr(transparent)] -/// pub struct Example { -/// inner: ManuallyDrop, -/// } -/// -/// unsafe impl Wrapper for Example { -/// type Wrapped = String; -/// } -/// ``` -/// -/// # Safety -/// -/// `Self` must be a `#[repr(transparent)]` wrapper for the `Wrapped` type, -/// whether directly or indirectly. -/// -/// # Methods -/// -/// By convention, types that implement Wrapper also implement the following -/// methods: -/// -/// ```ignore -/// pub const unsafe fn from_raw<'a>(value: *mut Self::Wrapped) -> &'a Self; -/// pub const unsafe fn as_mut_ptr(&self) -> *mut Self::Wrapped; -/// pub const unsafe fn as_ptr(&self) -> *const Self::Wrapped; -/// pub const unsafe fn raw_get(slot: *mut Self) -> *const Self::Wrapped; -/// ``` -/// -/// They are not defined here to allow them to be `const`. -pub unsafe trait Wrapper { - type Wrapped; -} - -unsafe impl Wrapper for Opaque { - type Wrapped = T; -} diff --git a/rust/qemu-api/src/chardev.rs b/rust/qemu-api/src/chardev.rs index cb27be52569..5a351dcecb0 100644 --- a/rust/qemu-api/src/chardev.rs +++ b/rust/qemu-api/src/chardev.rs @@ -18,10 +18,11 @@ use std::{ slice, }; +use common::{callbacks::FnCall, errno, Opaque}; + use crate::{ bindings, - callbacks::FnCall, - cell::{BqlRefMut, Opaque}, + cell::{BqlRefCell, BqlRefMut}, prelude::*, }; diff --git a/rust/qemu-api/src/error.rs b/rust/qemu-api/src/error.rs index e114fc4178b..8bac3cbec81 100644 --- a/rust/qemu-api/src/error.rs +++ b/rust/qemu-api/src/error.rs @@ -316,10 +316,11 @@ mod tests { use std::ffi::CStr; use anyhow::anyhow; + use common::assert_match; use foreign::OwnedPointer; use super::*; - use crate::{assert_match, bindings}; + use crate::bindings; #[track_caller] fn error_for_test(msg: &CStr) -> OwnedPointer { diff --git a/rust/qemu-api/src/irq.rs b/rust/qemu-api/src/irq.rs index 1526e6f63a1..ea6b32848c5 100644 --- a/rust/qemu-api/src/irq.rs +++ b/rust/qemu-api/src/irq.rs @@ -10,9 +10,10 @@ use std::{ ptr, }; +use common::Opaque; + use crate::{ bindings::{self, qemu_set_irq}, - cell::Opaque, prelude::*, qom::ObjectClass, }; diff --git a/rust/qemu-api/src/lib.rs b/rust/qemu-api/src/lib.rs index daa2493bb69..6232e39e711 100644 --- a/rust/qemu-api/src/lib.rs +++ b/rust/qemu-api/src/lib.rs @@ -13,12 +13,8 @@ pub mod bindings; #[rustfmt::skip] pub mod prelude; -pub mod assertions; -pub mod bitops; -pub mod callbacks; pub mod cell; pub mod chardev; -pub mod errno; pub mod error; pub mod irq; pub mod log; @@ -28,9 +24,7 @@ pub mod qdev; pub mod qom; pub mod sysbus; pub mod timer; -pub mod uninit; pub mod vmstate; -pub mod zeroable; // Allow proc-macros to refer to `::qemu_api` inside the `qemu_api` crate (this // crate). diff --git a/rust/qemu-api/src/log.rs b/rust/qemu-api/src/log.rs index a441b8c1f2e..d07f6272dc1 100644 --- a/rust/qemu-api/src/log.rs +++ b/rust/qemu-api/src/log.rs @@ -8,7 +8,9 @@ use std::{ ptr::NonNull, }; -use crate::{bindings, errno}; +use common::errno; + +use crate::bindings; #[repr(u32)] /// Represents specific error categories within QEMU's logging system. diff --git a/rust/qemu-api/src/memory.rs b/rust/qemu-api/src/memory.rs index e40fad6cf19..f790cb5fd2d 100644 --- a/rust/qemu-api/src/memory.rs +++ b/rust/qemu-api/src/memory.rs @@ -10,14 +10,11 @@ use std::{ }; pub use bindings::{hwaddr, MemTxAttrs}; +use common::{callbacks::FnCall, uninit::MaybeUninitField, zeroable::Zeroable, Opaque}; use crate::{ bindings::{self, device_endian, memory_region_init_io}, - callbacks::FnCall, - cell::Opaque, prelude::*, - uninit::MaybeUninitField, - zeroable::Zeroable, }; pub struct MemoryRegionOps( diff --git a/rust/qemu-api/src/prelude.rs b/rust/qemu-api/src/prelude.rs index 8f9e23ee2c5..dcfe71497f0 100644 --- a/rust/qemu-api/src/prelude.rs +++ b/rust/qemu-api/src/prelude.rs @@ -4,13 +4,9 @@ //! Commonly used traits and types for QEMU. -pub use crate::bitops::IntegerExt; - pub use crate::cell::BqlCell; pub use crate::cell::BqlRefCell; -pub use crate::errno; - pub use crate::log_mask_ln; pub use crate::qdev::DeviceMethods; @@ -19,8 +15,8 @@ pub use crate::qom::InterfaceType; pub use crate::qom::IsA; pub use crate::qom::Object; pub use crate::qom::ObjectCast; -pub use crate::qom::ObjectDeref; pub use crate::qom::ObjectClassMethods; +pub use crate::qom::ObjectDeref; pub use crate::qom::ObjectMethods; pub use crate::qom::ObjectType; diff --git a/rust/qemu-api/src/qdev.rs b/rust/qemu-api/src/qdev.rs index e2b4121cac5..8be125fae47 100644 --- a/rust/qemu-api/src/qdev.rs +++ b/rust/qemu-api/src/qdev.rs @@ -10,11 +10,11 @@ use std::{ }; pub use bindings::{ClockEvent, DeviceClass, Property, ResetType}; +use common::{callbacks::FnCall, Opaque}; use crate::{ bindings::{self, qdev_init_gpio_in, qdev_init_gpio_out, ResettableClass}, - callbacks::FnCall, - cell::{bql_locked, Opaque}, + cell::bql_locked, chardev::Chardev, error::{Error, Result}, impl_vmstate_c_struct, @@ -246,7 +246,7 @@ macro_rules! define_property { bitnr: $bitnr, set_default: true, defval: $crate::bindings::Property__bindgen_ty_1 { u: $defval as u64 }, - ..$crate::zeroable::Zeroable::ZERO + ..::common::zeroable::Zeroable::ZERO } }; ($name:expr, $state:ty, $field:ident, $prop:expr, $type:ty, default = $defval:expr$(,)*) => { @@ -257,7 +257,7 @@ macro_rules! define_property { offset: ::std::mem::offset_of!($state, $field) as isize, set_default: true, defval: $crate::bindings::Property__bindgen_ty_1 { u: $defval as u64 }, - ..$crate::zeroable::Zeroable::ZERO + ..::common::zeroable::Zeroable::ZERO } }; ($name:expr, $state:ty, $field:ident, $prop:expr, $type:ty$(,)*) => { @@ -267,7 +267,7 @@ macro_rules! define_property { info: $prop, offset: ::std::mem::offset_of!($state, $field) as isize, set_default: false, - ..$crate::zeroable::Zeroable::ZERO + ..::common::zeroable::Zeroable::ZERO } }; } diff --git a/rust/qemu-api/src/qom.rs b/rust/qemu-api/src/qom.rs index 12c6fc6752c..49b4f03ccfc 100644 --- a/rust/qemu-api/src/qom.rs +++ b/rust/qemu-api/src/qom.rs @@ -102,13 +102,14 @@ use std::{ }; pub use bindings::ObjectClass; +use common::Opaque; use crate::{ bindings::{ self, object_class_dynamic_cast, object_dynamic_cast, object_get_class, object_get_typename, object_new, object_ref, object_unref, TypeInfo, }, - cell::{bql_locked, Opaque}, + cell::bql_locked, impl_vmstate_pointer, }; diff --git a/rust/qemu-api/src/sysbus.rs b/rust/qemu-api/src/sysbus.rs index e92502a8fe6..4a5b4cbbf67 100644 --- a/rust/qemu-api/src/sysbus.rs +++ b/rust/qemu-api/src/sysbus.rs @@ -7,10 +7,11 @@ use std::{ffi::CStr, ptr::addr_of_mut}; pub use bindings::SysBusDeviceClass; +use common::Opaque; use crate::{ bindings, - cell::{bql_locked, Opaque}, + cell::bql_locked, irq::{IRQState, InterruptSource}, memory::MemoryRegion, prelude::*, diff --git a/rust/qemu-api/src/timer.rs b/rust/qemu-api/src/timer.rs index 1e639eaf221..383e1a6e774 100644 --- a/rust/qemu-api/src/timer.rs +++ b/rust/qemu-api/src/timer.rs @@ -7,10 +7,10 @@ use std::{ pin::Pin, }; -use crate::{ - bindings::{self, qemu_clock_get_ns, timer_del, timer_init_full, timer_mod, QEMUClockType}, - callbacks::FnCall, - cell::Opaque, +use common::{callbacks::FnCall, Opaque}; + +use crate::bindings::{ + self, qemu_clock_get_ns, timer_del, timer_init_full, timer_mod, QEMUClockType, }; /// A safe wrapper around [`bindings::QEMUTimer`]. diff --git a/rust/qemu-api/src/vmstate.rs b/rust/qemu-api/src/vmstate.rs index ce42b031bc1..06aac3a73f4 100644 --- a/rust/qemu-api/src/vmstate.rs +++ b/rust/qemu-api/src/vmstate.rs @@ -35,14 +35,15 @@ use std::{ ptr::{addr_of, NonNull}, }; -pub use crate::bindings::{MigrationPriority, VMStateField}; -use crate::{ - bindings::{self, VMStateFlags}, +use common::{ callbacks::FnCall, errno::{into_neg_errno, Errno}, - zeroable::Zeroable, + Zeroable, }; +use crate::bindings::{self, VMStateFlags}; +pub use crate::bindings::{MigrationPriority, VMStateField}; + /// This macro is used to call a function with a generic argument bound /// to the type of a field. The function must take a /// [`PhantomData`]`` argument; `T` is the type of @@ -271,7 +272,7 @@ macro_rules! impl_vmstate_transparent { impl_vmstate_transparent!(std::cell::Cell where T: VMState); impl_vmstate_transparent!(std::cell::UnsafeCell where T: VMState); impl_vmstate_transparent!(std::pin::Pin where T: VMState); -impl_vmstate_transparent!(crate::cell::Opaque where T: VMState); +impl_vmstate_transparent!(::common::Opaque where T: VMState); #[macro_export] macro_rules! impl_vmstate_bitsized { @@ -324,7 +325,7 @@ macro_rules! impl_vmstate_c_struct { vmsd: ::std::ptr::addr_of!($vmsd), size: ::std::mem::size_of::<$type>(), flags: $crate::bindings::VMStateFlags::VMS_STRUCT, - ..$crate::zeroable::Zeroable::ZERO + ..common::zeroable::Zeroable::ZERO }; } }; @@ -367,7 +368,7 @@ macro_rules! vmstate_unused { size: $size, info: unsafe { ::core::ptr::addr_of!($crate::bindings::vmstate_info_unused_buffer) }, flags: $crate::bindings::VMStateFlags::VMS_BUFFER, - ..$crate::zeroable::Zeroable::ZERO + ..::common::Zeroable::ZERO } }}; } @@ -390,7 +391,7 @@ pub type VMSFieldExistCb = unsafe extern "C" fn( #[macro_export] macro_rules! vmstate_exist_fn { ($struct_name:ty, $test_fn:expr) => {{ - const fn test_cb_builder__ $crate::callbacks::FnCall<(&'a T, u8), bool>>( + const fn test_cb_builder__ ::common::callbacks::FnCall<(&'a T, u8), bool>>( _phantom: ::core::marker::PhantomData, ) -> $crate::vmstate::VMSFieldExistCb { const { assert!(F::IS_SOME) }; @@ -414,7 +415,7 @@ macro_rules! vmstate_fields { $($field),*, $crate::bindings::VMStateField { flags: $crate::bindings::VMStateFlags::VMS_END, - ..$crate::zeroable::Zeroable::ZERO + ..::common::zeroable::Zeroable::ZERO } ]; _FIELDS.as_ptr() @@ -433,7 +434,7 @@ macro_rules! vmstate_validate { | $crate::bindings::VMStateFlags::VMS_ARRAY.0, ), num: 0, // 0 elements: no data, only run test_fn callback - ..$crate::zeroable::Zeroable::ZERO + ..::common::zeroable::Zeroable::ZERO } }; } @@ -455,7 +456,7 @@ macro_rules! impl_vmstate_struct { vmsd: ::core::ptr::addr_of!(*VMSD), size: ::core::mem::size_of::<$type>(), flags: $crate::bindings::VMStateFlags::VMS_STRUCT, - ..$crate::zeroable::Zeroable::ZERO + ..common::Zeroable::ZERO } }; } diff --git a/rust/qemu-api/src/zeroable.rs b/rust/qemu-api/src/zeroable.rs deleted file mode 100644 index d8239d08563..00000000000 --- a/rust/qemu-api/src/zeroable.rs +++ /dev/null @@ -1,37 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0-or-later - -//! Defines a trait for structs that can be safely initialized with zero bytes. - -/// Encapsulates the requirement that -/// `MaybeUninit::::zeroed().assume_init()` does not cause undefined -/// behavior. -/// -/// # Safety -/// -/// Do not add this trait to a type unless all-zeroes is a valid value for the -/// type. In particular, raw pointers can be zero, but references and -/// `NonNull` cannot. -pub unsafe trait Zeroable: Default { - /// Return a value of Self whose memory representation consists of all - /// zeroes, with the possible exclusion of padding bytes. - const ZERO: Self = unsafe { ::core::mem::MaybeUninit::::zeroed().assume_init() }; -} - -// bindgen does not derive Default here -#[allow(clippy::derivable_impls)] -impl Default for crate::bindings::VMStateFlags { - fn default() -> Self { - Self(0) - } -} - -unsafe impl Zeroable for crate::bindings::Property__bindgen_ty_1 {} -unsafe impl Zeroable for crate::bindings::Property {} -unsafe impl Zeroable for crate::bindings::VMStateFlags {} -unsafe impl Zeroable for crate::bindings::VMStateField {} -unsafe impl Zeroable for crate::bindings::VMStateDescription {} -unsafe impl Zeroable for crate::bindings::MemoryRegionOps__bindgen_ty_1 {} -unsafe impl Zeroable for crate::bindings::MemoryRegionOps__bindgen_ty_2 {} -unsafe impl Zeroable for crate::bindings::MemoryRegionOps {} -unsafe impl Zeroable for crate::bindings::MemTxAttrs {} -unsafe impl Zeroable for crate::bindings::CharBackend {} diff --git a/rust/qemu-api/tests/vmstate_tests.rs b/rust/qemu-api/tests/vmstate_tests.rs index 2c0670ba0ee..d9e5bcc4987 100644 --- a/rust/qemu-api/tests/vmstate_tests.rs +++ b/rust/qemu-api/tests/vmstate_tests.rs @@ -9,12 +9,13 @@ use std::{ slice, }; +use common::Opaque; use qemu_api::{ bindings::{ vmstate_info_bool, vmstate_info_int32, vmstate_info_int64, vmstate_info_int8, vmstate_info_uint64, vmstate_info_uint8, vmstate_info_unused_buffer, VMStateFlags, }, - cell::{BqlCell, Opaque}, + cell::BqlCell, impl_vmstate_forward, impl_vmstate_struct, vmstate::{VMStateDescription, VMStateDescriptionBuilder, VMStateField}, vmstate_fields, vmstate_of, vmstate_unused, vmstate_validate,