diff options
Diffstat (limited to 'rust/util')
| -rw-r--r-- | rust/util/Cargo.toml | 23 | ||||
| -rw-r--r-- | rust/util/build.rs | 49 | ||||
| -rw-r--r-- | rust/util/meson.build | 55 | ||||
| -rw-r--r-- | rust/util/src/bindings.rs | 25 | ||||
| -rw-r--r-- | rust/util/src/error.rs | 416 | ||||
| -rw-r--r-- | rust/util/src/lib.rs | 9 | ||||
| -rw-r--r-- | rust/util/src/log.rs | 151 | ||||
| -rw-r--r-- | rust/util/src/module.rs | 43 | ||||
| -rw-r--r-- | rust/util/src/timer.rs | 125 | ||||
| -rw-r--r-- | rust/util/wrapper.h | 32 |
10 files changed, 928 insertions, 0 deletions
diff --git a/rust/util/Cargo.toml b/rust/util/Cargo.toml new file mode 100644 index 0000000000..637df61060 --- /dev/null +++ b/rust/util/Cargo.toml @@ -0,0 +1,23 @@ +[package] +name = "util" +version = "0.1.0" +description = "Rust bindings for QEMU/util" +resolver = "2" +publish = false + +authors.workspace = true +edition.workspace = true +homepage.workspace = true +license.workspace = true +repository.workspace = true +rust-version.workspace = true + +[dependencies] +anyhow = { workspace = true } +foreign = { workspace = true } +libc = { workspace = true } +common = { path = "../common" } +qemu_api_macros = { path = "../qemu-api-macros" } + +[lints] +workspace = true diff --git a/rust/util/build.rs b/rust/util/build.rs new file mode 100644 index 0000000000..5654d1d562 --- /dev/null +++ b/rust/util/build.rs @@ -0,0 +1,49 @@ +// Copyright 2024, Linaro Limited +// Author(s): Manos Pitsidianakis <manos.pitsidianakis@linaro.org> +// SPDX-License-Identifier: GPL-2.0-or-later + +#[cfg(unix)] +use std::os::unix::fs::symlink as symlink_file; +#[cfg(windows)] +use std::os::windows::fs::symlink_file; +use std::{env, fs::remove_file, io::Result, path::Path}; + +fn main() -> Result<()> { + let manifest_dir = env!("CARGO_MANIFEST_DIR"); + let file = if let Ok(root) = env::var("MESON_BUILD_ROOT") { + let sub = get_rust_subdir(manifest_dir).unwrap(); + format!("{root}/{sub}/bindings.inc.rs") + } else { + // Placing bindings.inc.rs in the source directory is supported + // but not documented or encouraged. + format!("{manifest_dir}/src/bindings.inc.rs") + }; + + let file = Path::new(&file); + if !Path::new(&file).exists() { + panic!(concat!( + "\n", + " No generated C bindings found! Maybe you wanted one of\n", + " `make clippy`, `make rustfmt`, `make rustdoc`?\n", + "\n", + " For other uses of `cargo`, start a subshell with\n", + " `pyvenv/bin/meson devenv`, or point MESON_BUILD_ROOT to\n", + " the top of the build tree." + )); + } + + let out_dir = env::var("OUT_DIR").unwrap(); + let dest_path = format!("{out_dir}/bindings.inc.rs"); + let dest_path = Path::new(&dest_path); + if dest_path.symlink_metadata().is_ok() { + remove_file(dest_path)?; + } + symlink_file(file, dest_path)?; + + println!("cargo:rerun-if-changed=build.rs"); + Ok(()) +} + +fn get_rust_subdir(path: &str) -> Option<&str> { + path.find("/rust").map(|index| &path[index + 1..]) +} diff --git a/rust/util/meson.build b/rust/util/meson.build new file mode 100644 index 0000000000..56e929349b --- /dev/null +++ b/rust/util/meson.build @@ -0,0 +1,55 @@ +_util_bindgen_args = [] +c_enums = [ + 'module_init_type', + 'QEMUClockType', +] +foreach enum : c_enums + _util_bindgen_args += ['--rustified-enum', enum] +endforeach + +# +# TODO: Remove this comment when the clang/libclang mismatch issue is solved. +# +# Rust bindings generation with `bindgen` might fail in some cases where the +# detected `libclang` does not match the expected `clang` version/target. In +# this case you must pass the path to `clang` and `libclang` to your build +# command invocation using the environment variables CLANG_PATH and +# LIBCLANG_PATH +_util_bindings_inc_rs = rust.bindgen( + input: 'wrapper.h', + dependencies: common_ss.all_dependencies(), + output: 'bindings.inc.rs', + include_directories: bindings_incdir, + bindgen_version: ['>=0.60.0'], + args: bindgen_args_common + _util_bindgen_args, +) + +_util_rs = static_library( + 'util', + structured_sources( + [ + 'src/lib.rs', + 'src/bindings.rs', + 'src/error.rs', + 'src/log.rs', + 'src/module.rs', + 'src/timer.rs', + ], + {'.': _util_bindings_inc_rs} + ), + override_options: ['rust_std=2021', 'build.rust_std=2021'], + rust_abi: 'rust', + dependencies: [anyhow_rs, libc_rs, foreign_rs, common_rs, qemu_api_macros, qom, qemuutil], +) + +util_rs = declare_dependency(link_with: [_util_rs], dependencies: [qemuutil, qom]) + +# 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-util-rs-doctests', + _util_rs, + protocol: 'rust', + dependencies: util_rs, + suite: ['doc', 'rust'] +) diff --git a/rust/util/src/bindings.rs b/rust/util/src/bindings.rs new file mode 100644 index 0000000000..9ffff12cde --- /dev/null +++ b/rust/util/src/bindings.rs @@ -0,0 +1,25 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +#![allow( + dead_code, + improper_ctypes_definitions, + improper_ctypes, + non_camel_case_types, + non_snake_case, + non_upper_case_globals, + unnecessary_transmutes, + unsafe_op_in_unsafe_fn, + clippy::pedantic, + clippy::restriction, + clippy::style, + clippy::missing_const_for_fn, + clippy::ptr_offset_with_cast, + clippy::useless_transmute, + clippy::missing_safety_doc, + clippy::too_many_arguments +)] + +#[cfg(MESON)] +include!("bindings.inc.rs"); + +#[cfg(not(MESON))] +include!(concat!(env!("OUT_DIR"), "/bindings.inc.rs")); diff --git a/rust/util/src/error.rs b/rust/util/src/error.rs new file mode 100644 index 0000000000..bfa5a8685b --- /dev/null +++ b/rust/util/src/error.rs @@ -0,0 +1,416 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +//! Error propagation for QEMU Rust code +//! +//! This module contains [`Error`], the bridge between Rust errors and +//! [`Result`](std::result::Result)s and QEMU's C [`Error`](bindings::Error) +//! struct. +//! +//! For FFI code, [`Error`] provides functions to simplify conversion between +//! the Rust ([`Result<>`](std::result::Result)) and C (`Error**`) conventions: +//! +//! * [`ok_or_propagate`](crate::Error::ok_or_propagate), +//! [`bool_or_propagate`](crate::Error::bool_or_propagate), +//! [`ptr_or_propagate`](crate::Error::ptr_or_propagate) can be used to build +//! a C return value while also propagating an error condition +//! +//! * [`err_or_else`](crate::Error::err_or_else) and +//! [`err_or_unit`](crate::Error::err_or_unit) can be used to build a `Result` +//! +//! This module is most commonly used at the boundary between C and Rust code; +//! other code will usually access it through the +//! [`utils::Result`](crate::Result) type alias, and will use the +//! [`std::error::Error`] interface to let C errors participate in Rust's error +//! handling functionality. +//! +//! Rust code can also create use this module to create an error object that +//! will be passed up to C code, though in most cases this will be done +//! transparently through the `?` operator. Errors can be constructed from a +//! simple error string, from an [`anyhow::Error`] to pass any other Rust error +//! type up to C code, or from a combination of the two. +//! +//! The third case, corresponding to [`Error::with_error`], is the only one that +//! requires mentioning [`utils::Error`](crate::Error) explicitly. Similar +//! to how QEMU's C code handles errno values, the string and the +//! `anyhow::Error` object will be concatenated with `:` as the separator. + +use std::{ + borrow::Cow, + ffi::{c_char, c_int, c_void, CStr}, + fmt::{self, Display}, + panic, ptr, +}; + +use foreign::{prelude::*, OwnedPointer}; + +use crate::bindings; + +pub type Result<T> = std::result::Result<T, Error>; + +#[derive(Debug)] +pub struct Error { + msg: Option<Cow<'static, str>>, + /// Appends the print string of the error to the msg if not None + cause: Option<anyhow::Error>, + file: &'static str, + line: u32, +} + +impl std::error::Error for Error { + fn source(&self) -> Option<&(dyn std::error::Error + 'static)> { + self.cause.as_ref().map(AsRef::as_ref) + } + + #[allow(deprecated)] + fn description(&self) -> &str { + self.msg + .as_deref() + .or_else(|| self.cause.as_deref().map(std::error::Error::description)) + .expect("no message nor cause?") + } +} + +impl Display for Error { + fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { + let mut prefix = ""; + if let Some(ref msg) = self.msg { + write!(f, "{msg}")?; + prefix = ": "; + } + if let Some(ref cause) = self.cause { + write!(f, "{prefix}{cause}")?; + } else if prefix.is_empty() { + panic!("no message nor cause?"); + } + Ok(()) + } +} + +impl From<String> for Error { + #[track_caller] + fn from(msg: String) -> Self { + let location = panic::Location::caller(); + Error { + msg: Some(Cow::Owned(msg)), + cause: None, + file: location.file(), + line: location.line(), + } + } +} + +impl From<&'static str> for Error { + #[track_caller] + fn from(msg: &'static str) -> Self { + let location = panic::Location::caller(); + Error { + msg: Some(Cow::Borrowed(msg)), + cause: None, + file: location.file(), + line: location.line(), + } + } +} + +impl From<anyhow::Error> for Error { + #[track_caller] + fn from(error: anyhow::Error) -> Self { + let location = panic::Location::caller(); + Error { + msg: None, + cause: Some(error), + file: location.file(), + line: location.line(), + } + } +} + +impl Error { + /// Create a new error, prepending `msg` to the + /// description of `cause` + #[track_caller] + pub fn with_error(msg: impl Into<Cow<'static, str>>, cause: impl Into<anyhow::Error>) -> Self { + let location = panic::Location::caller(); + Error { + msg: Some(msg.into()), + cause: Some(cause.into()), + file: location.file(), + line: location.line(), + } + } + + /// Consume a result, returning `false` if it is an error and + /// `true` if it is successful. The error is propagated into + /// `errp` like the C API `error_propagate` would do. + /// + /// # Safety + /// + /// `errp` must be a valid argument to `error_propagate`; + /// typically it is received from C code and need not be + /// checked further at the Rust↔C boundary. + pub unsafe fn bool_or_propagate(result: Result<()>, errp: *mut *mut bindings::Error) -> bool { + // SAFETY: caller guarantees errp is valid + unsafe { Self::ok_or_propagate(result, errp) }.is_some() + } + + /// Consume a result, returning a `NULL` pointer if it is an error and + /// a C representation of the contents if it is successful. This is + /// similar to the C API `error_propagate`, but it panics if `*errp` + /// is not `NULL`. + /// + /// # Safety + /// + /// `errp` must be a valid argument to `error_propagate`; + /// typically it is received from C code and need not be + /// checked further at the Rust↔C boundary. + /// + /// See [`propagate`](Error::propagate) for more information. + #[must_use] + pub unsafe fn ptr_or_propagate<T: CloneToForeign>( + result: Result<T>, + errp: *mut *mut bindings::Error, + ) -> *mut T::Foreign { + // SAFETY: caller guarantees errp is valid + unsafe { Self::ok_or_propagate(result, errp) }.clone_to_foreign_ptr() + } + + /// Consume a result in the same way as `self.ok()`, but also propagate + /// a possible error into `errp`. This is similar to the C API + /// `error_propagate`, but it panics if `*errp` is not `NULL`. + /// + /// # Safety + /// + /// `errp` must be a valid argument to `error_propagate`; + /// typically it is received from C code and need not be + /// checked further at the Rust↔C boundary. + /// + /// See [`propagate`](Error::propagate) for more information. + pub unsafe fn ok_or_propagate<T>( + result: Result<T>, + errp: *mut *mut bindings::Error, + ) -> Option<T> { + result.map_err(|err| unsafe { err.propagate(errp) }).ok() + } + + /// Equivalent of the C function `error_propagate`. Fill `*errp` + /// with the information container in `self` if `errp` is not NULL; + /// then consume it. + /// + /// This is similar to the C API `error_propagate`, but it panics if + /// `*errp` is not `NULL`. + /// + /// # Safety + /// + /// `errp` must be a valid argument to `error_propagate`; it can be + /// `NULL` or it can point to any of: + /// * `error_abort` + /// * `error_fatal` + /// * a local variable of (C) type `Error *` + /// + /// Typically `errp` is received from C code and need not be + /// checked further at the Rust↔C boundary. + pub unsafe fn propagate(self, errp: *mut *mut bindings::Error) { + if errp.is_null() { + return; + } + + // SAFETY: caller guarantees that errp and *errp are valid + unsafe { + assert_eq!(*errp, ptr::null_mut()); + bindings::error_propagate(errp, self.clone_to_foreign_ptr()); + } + } + + /// Convert a C `Error*` into a Rust `Result`, using + /// `Ok(())` if `c_error` is NULL. Free the `Error*`. + /// + /// # Safety + /// + /// `c_error` must be `NULL` or valid; typically it was initialized + /// with `ptr::null_mut()` and passed by reference to a C function. + pub unsafe fn err_or_unit(c_error: *mut bindings::Error) -> Result<()> { + // SAFETY: caller guarantees c_error is valid + unsafe { Self::err_or_else(c_error, || ()) } + } + + /// Convert a C `Error*` into a Rust `Result`, calling `f()` to + /// obtain an `Ok` value if `c_error` is NULL. Free the `Error*`. + /// + /// # Safety + /// + /// `c_error` must be `NULL` or point to a valid C [`struct + /// Error`](bindings::Error); typically it was initialized with + /// `ptr::null_mut()` and passed by reference to a C function. + pub unsafe fn err_or_else<T, F: FnOnce() -> T>( + c_error: *mut bindings::Error, + f: F, + ) -> Result<T> { + // SAFETY: caller guarantees c_error is valid + let err = unsafe { Option::<Self>::from_foreign(c_error) }; + match err { + None => Ok(f()), + Some(err) => Err(err), + } + } +} + +impl FreeForeign for Error { + type Foreign = bindings::Error; + + unsafe fn free_foreign(p: *mut bindings::Error) { + // SAFETY: caller guarantees p is valid + unsafe { + bindings::error_free(p); + } + } +} + +impl CloneToForeign for Error { + fn clone_to_foreign(&self) -> OwnedPointer<Self> { + // SAFETY: all arguments are controlled by this function + unsafe { + let err: *mut c_void = libc::malloc(std::mem::size_of::<bindings::Error>()); + let err: &mut bindings::Error = &mut *err.cast(); + *err = bindings::Error { + msg: format!("{self}").clone_to_foreign_ptr(), + err_class: bindings::ERROR_CLASS_GENERIC_ERROR, + src_len: self.file.len() as c_int, + src: self.file.as_ptr().cast::<c_char>(), + line: self.line as c_int, + func: ptr::null_mut(), + hint: ptr::null_mut(), + }; + OwnedPointer::new(err) + } + } +} + +impl FromForeign for Error { + unsafe fn cloned_from_foreign(c_error: *const bindings::Error) -> Self { + // SAFETY: caller guarantees c_error is valid + unsafe { + let error = &*c_error; + let file = if error.src_len < 0 { + // NUL-terminated + CStr::from_ptr(error.src).to_str() + } else { + // Can become str::from_utf8 with Rust 1.87.0 + std::str::from_utf8(std::slice::from_raw_parts( + &*error.src.cast::<u8>(), + error.src_len as usize, + )) + }; + + Error { + msg: FromForeign::cloned_from_foreign(error.msg), + cause: None, + file: file.unwrap(), + line: error.line as u32, + } + } + } +} + +#[cfg(test)] +mod tests { + use std::ffi::CStr; + + use anyhow::anyhow; + use common::assert_match; + use foreign::OwnedPointer; + + use super::*; + + #[track_caller] + fn error_for_test(msg: &CStr) -> OwnedPointer<Error> { + // SAFETY: all arguments are controlled by this function + let location = panic::Location::caller(); + unsafe { + let err: *mut c_void = libc::malloc(std::mem::size_of::<bindings::Error>()); + let err: &mut bindings::Error = &mut *err.cast(); + *err = bindings::Error { + msg: msg.clone_to_foreign_ptr(), + err_class: bindings::ERROR_CLASS_GENERIC_ERROR, + src_len: location.file().len() as c_int, + src: location.file().as_ptr().cast::<c_char>(), + line: location.line() as c_int, + func: ptr::null_mut(), + hint: ptr::null_mut(), + }; + OwnedPointer::new(err) + } + } + + unsafe fn error_get_pretty<'a>(local_err: *mut bindings::Error) -> &'a CStr { + unsafe { CStr::from_ptr(bindings::error_get_pretty(local_err)) } + } + + #[test] + #[allow(deprecated)] + fn test_description() { + use std::error::Error; + + assert_eq!(super::Error::from("msg").description(), "msg"); + assert_eq!(super::Error::from("msg".to_owned()).description(), "msg"); + } + + #[test] + fn test_display() { + assert_eq!(&*format!("{}", Error::from("msg")), "msg"); + assert_eq!(&*format!("{}", Error::from("msg".to_owned())), "msg"); + assert_eq!(&*format!("{}", Error::from(anyhow!("msg"))), "msg"); + + assert_eq!( + &*format!("{}", Error::with_error("msg", anyhow!("cause"))), + "msg: cause" + ); + } + + #[test] + fn test_bool_or_propagate() { + unsafe { + let mut local_err: *mut bindings::Error = ptr::null_mut(); + + assert!(Error::bool_or_propagate(Ok(()), &mut local_err)); + assert_eq!(local_err, ptr::null_mut()); + + let my_err = Error::from("msg"); + assert!(!Error::bool_or_propagate(Err(my_err), &mut local_err)); + assert_ne!(local_err, ptr::null_mut()); + assert_eq!(error_get_pretty(local_err), c"msg"); + bindings::error_free(local_err); + } + } + + #[test] + fn test_ptr_or_propagate() { + unsafe { + let mut local_err: *mut bindings::Error = ptr::null_mut(); + + let ret = Error::ptr_or_propagate(Ok("abc".to_owned()), &mut local_err); + assert_eq!(String::from_foreign(ret), "abc"); + assert_eq!(local_err, ptr::null_mut()); + + let my_err = Error::from("msg"); + assert_eq!( + Error::ptr_or_propagate(Err::<String, _>(my_err), &mut local_err), + ptr::null_mut() + ); + assert_ne!(local_err, ptr::null_mut()); + assert_eq!(error_get_pretty(local_err), c"msg"); + bindings::error_free(local_err); + } + } + + #[test] + fn test_err_or_unit() { + unsafe { + let result = Error::err_or_unit(ptr::null_mut()); + assert_match!(result, Ok(())); + + let err = error_for_test(c"msg"); + let err = Error::err_or_unit(err.into_inner()).unwrap_err(); + assert_eq!(&*format!("{err}"), "msg"); + } + } +} diff --git a/rust/util/src/lib.rs b/rust/util/src/lib.rs new file mode 100644 index 0000000000..16c89b9517 --- /dev/null +++ b/rust/util/src/lib.rs @@ -0,0 +1,9 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +pub mod bindings; +pub mod error; +pub mod log; +pub mod module; +pub mod timer; + +pub use error::{Error, Result}; diff --git a/rust/util/src/log.rs b/rust/util/src/log.rs new file mode 100644 index 0000000000..af9a3e9123 --- /dev/null +++ b/rust/util/src/log.rs @@ -0,0 +1,151 @@ +// Copyright 2025 Bernhard Beschow <shentey@gmail.com> +// SPDX-License-Identifier: GPL-2.0-or-later + +//! Bindings for QEMU's logging infrastructure + +use std::{ + io::{self, Write}, + ptr::NonNull, +}; + +use common::errno; + +use crate::bindings; + +#[repr(u32)] +/// Represents specific error categories within QEMU's logging system. +/// +/// The `Log` enum provides a Rust abstraction for logging errors, corresponding +/// to a subset of the error categories defined in the C implementation. +pub enum Log { + /// Log invalid access caused by the guest. + /// Corresponds to `LOG_GUEST_ERROR` in the C implementation. + GuestError = bindings::LOG_GUEST_ERROR, + + /// Log guest access of unimplemented functionality. + /// Corresponds to `LOG_UNIMP` in the C implementation. + Unimp = bindings::LOG_UNIMP, +} + +/// A RAII guard for QEMU's logging infrastructure. Creating the guard +/// locks the log file, and dropping it (letting it go out of scope) unlocks +/// the file. +/// +/// As long as the guard lives, it can be written to using [`std::io::Write`]. +/// +/// The locking is recursive, therefore owning a guard does not prevent +/// using [`log_mask_ln!()`](crate::log_mask_ln). +pub struct LogGuard(NonNull<bindings::FILE>); + +impl LogGuard { + /// Return a RAII guard that writes to QEMU's logging infrastructure. + /// The log file is locked while the guard exists, ensuring that there + /// is no tearing of the messages. + /// + /// Return `None` if the log file is closed and could not be opened. + /// Do *not* use `unwrap()` on the result; failure can be handled simply + /// by not logging anything. + /// + /// # Examples + /// + /// ``` + /// # use util::log::LogGuard; + /// # use std::io::Write; + /// if let Some(mut log) = LogGuard::new() { + /// writeln!(log, "test"); + /// } + /// ``` + pub fn new() -> Option<Self> { + let f = unsafe { bindings::qemu_log_trylock() }.cast(); + NonNull::new(f).map(Self) + } + + /// Writes a formatted string into the log, returning any error encountered. + /// + /// This method is primarily used by the + /// [`log_mask_ln!()`](crate::log_mask_ln) macro, and it is rare for it + /// to be called explicitly. It is public because it is the only way to + /// examine the error, which `log_mask_ln!()` ignores + /// + /// Unlike `log_mask_ln!()`, it does *not* append a newline at the end. + pub fn log_fmt(args: std::fmt::Arguments) -> io::Result<()> { + if let Some(mut log) = Self::new() { + log.write_fmt(args)?; + } + Ok(()) + } +} + +impl Write for LogGuard { + fn write(&mut self, bytes: &[u8]) -> io::Result<usize> { + let ret = unsafe { + bindings::rust_fwrite(bytes.as_ptr().cast(), 1, bytes.len(), self.0.as_ptr()) + }; + errno::into_io_result(ret) + } + + fn flush(&mut self) -> io::Result<()> { + // Do nothing, dropping the guard takes care of flushing + Ok(()) + } +} + +impl Drop for LogGuard { + fn drop(&mut self) { + unsafe { + bindings::qemu_log_unlock(self.0.as_ptr()); + } + } +} + +/// A macro to log messages conditionally based on a provided mask. +/// +/// The `log_mask_ln` macro checks whether the given mask matches the current +/// log level and, if so, formats and logs the message. It is the Rust +/// counterpart of the `qemu_log_mask()` macro in the C implementation. +/// +/// Errors from writing to the log are ignored. +/// +/// # Parameters +/// +/// - `$mask`: A log level mask. This should be a variant of the `Log` enum. +/// - `$fmt`: A format string following the syntax and rules of the `format!` +/// macro. It specifies the structure of the log message. +/// - `$args`: Optional arguments to be interpolated into the format string. +/// +/// # Example +/// +/// ``` +/// use util::{log::Log, log_mask_ln}; +/// +/// let error_address = 0xbad; +/// log_mask_ln!(Log::GuestError, "Address 0x{error_address:x} out of range"); +/// ``` +/// +/// It is also possible to use printf-style formatting, as well as having a +/// trailing `,`: +/// +/// ``` +/// use util::{log::Log, log_mask_ln}; +/// +/// let error_address = 0xbad; +/// log_mask_ln!( +/// Log::GuestError, +/// "Address 0x{:x} out of range", +/// error_address, +/// ); +/// ``` +#[macro_export] +macro_rules! log_mask_ln { + ($mask:expr, $fmt:tt $($args:tt)*) => {{ + // Type assertion to enforce type `Log` for $mask + let _: $crate::log::Log = $mask; + + if unsafe { + ($crate::bindings::qemu_loglevel & ($mask as std::os::raw::c_int)) != 0 + } { + _ = $crate::log::LogGuard::log_fmt( + format_args!("{}\n", format_args!($fmt $($args)*))); + } + }}; +} diff --git a/rust/util/src/module.rs b/rust/util/src/module.rs new file mode 100644 index 0000000000..06c45fc142 --- /dev/null +++ b/rust/util/src/module.rs @@ -0,0 +1,43 @@ +// Copyright 2024, Linaro Limited +// Author(s): Manos Pitsidianakis <manos.pitsidianakis@linaro.org> +// SPDX-License-Identifier: GPL-2.0-or-later + +//! Macro to register blocks of code that run as QEMU starts up. + +#[macro_export] +macro_rules! module_init { + ($type:ident => $body:block) => { + const _: () = { + #[used] + #[cfg_attr( + not(any(target_vendor = "apple", target_os = "windows")), + link_section = ".init_array" + )] + #[cfg_attr(target_vendor = "apple", link_section = "__DATA,__mod_init_func")] + #[cfg_attr(target_os = "windows", link_section = ".CRT$XCU")] + pub static LOAD_MODULE: extern "C" fn() = { + extern "C" fn init_fn() { + $body + } + + extern "C" fn ctor_fn() { + unsafe { + $crate::bindings::register_module_init( + Some(init_fn), + $crate::bindings::module_init_type::$type, + ); + } + } + + ctor_fn + }; + }; + }; + + // shortcut because it's quite common that $body needs unsafe {} + ($type:ident => unsafe $body:block) => { + ::util::module_init! { + $type => { unsafe { $body } } + } + }; +} diff --git a/rust/util/src/timer.rs b/rust/util/src/timer.rs new file mode 100644 index 0000000000..383e1a6e77 --- /dev/null +++ b/rust/util/src/timer.rs @@ -0,0 +1,125 @@ +// Copyright (C) 2024 Intel Corporation. +// Author(s): Zhao Liu <zhao1.liu@intel.com> +// SPDX-License-Identifier: GPL-2.0-or-later + +use std::{ + ffi::{c_int, c_void}, + pin::Pin, +}; + +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`]. +#[repr(transparent)] +#[derive(Debug, qemu_api_macros::Wrapper)] +pub struct Timer(Opaque<bindings::QEMUTimer>); + +unsafe impl Send for Timer {} +unsafe impl Sync for Timer {} + +#[repr(transparent)] +#[derive(qemu_api_macros::Wrapper)] +pub struct TimerListGroup(Opaque<bindings::QEMUTimerListGroup>); + +unsafe impl Send for TimerListGroup {} +unsafe impl Sync for TimerListGroup {} + +impl Timer { + pub const MS: u32 = bindings::SCALE_MS; + pub const US: u32 = bindings::SCALE_US; + pub const NS: u32 = bindings::SCALE_NS; + + /// Create a `Timer` struct without initializing it. + /// + /// # Safety + /// + /// The timer must be initialized before it is armed with + /// [`modify`](Self::modify). + pub const unsafe fn new() -> Self { + // SAFETY: requirements relayed to callers of Timer::new + Self(unsafe { Opaque::zeroed() }) + } + + /// Create a new timer with the given attributes. + pub fn init_full<'timer, 'opaque: 'timer, T, F>( + self: Pin<&'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,)>, + { + const { assert!(F::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.as_mut_ptr(), + 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>().cast_mut(), + ) + } + } + + pub fn modify(&self, expire_time: u64) { + // SAFETY: the only way to obtain a Timer safely is via methods that + // take a Pin<&mut Self>, therefore the timer is pinned + unsafe { timer_mod(self.as_mut_ptr(), expire_time as i64) } + } + + pub fn delete(&self) { + // SAFETY: the only way to obtain a Timer safely is via methods that + // take a Pin<&mut Self>, therefore the timer is pinned + unsafe { timer_del(self.as_mut_ptr()) } + } +} + +// FIXME: use something like PinnedDrop from the pinned_init crate +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, +}; + +pub const NANOSECONDS_PER_SECOND: u64 = 1000000000; diff --git a/rust/util/wrapper.h b/rust/util/wrapper.h new file mode 100644 index 0000000000..b9ed68a01d --- /dev/null +++ b/rust/util/wrapper.h @@ -0,0 +1,32 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ + +/* + * This header file is meant to be used as input to the `bindgen` application + * in order to generate C FFI compatible Rust bindings. + */ + +#ifndef __CLANG_STDATOMIC_H +#define __CLANG_STDATOMIC_H +/* + * Fix potential missing stdatomic.h error in case bindgen does not insert the + * correct libclang header paths on its own. We do not use stdatomic.h symbols + * in QEMU code, so it's fine to declare dummy types instead. + */ +typedef enum memory_order { + memory_order_relaxed, + memory_order_consume, + memory_order_acquire, + memory_order_release, + memory_order_acq_rel, + memory_order_seq_cst, +} memory_order; +#endif /* __CLANG_STDATOMIC_H */ + +#include "qemu/osdep.h" + +#include "qapi/error.h" +#include "qapi/error-internal.h" +#include "qemu/log-for-trace.h" +#include "qemu/log.h" +#include "qemu/module.h" +#include "qemu/timer.h" |