// SPDX-License-Identifier: GPL-2.0 //! The `kernel` crate.//!//! This crate contains the kernel APIs that have been ported or wrapped for//! usage by Rust code in the kernel and is shared by all of them.//!//! In other words, all the rest of the Rust code in the kernel (e.g. kernel//! modules written in Rust) depends on [`core`] and this crate.//!//! If you need a kernel C API that is not ported or wrapped yet here, then//! do so first instead of bypassing this crate. #![no_std]//// Please see https://github.com/Rust-for-Linux/linux/issues/2 for details on// the unstable features in use.//// Stable since Rust 1.79.0.#![feature(generic_nonzero)]#![feature(inline_const)]#![feature(pointer_is_aligned)]//// Stable since Rust 1.81.0.#![feature(lint_reasons)]//// Stable since Rust 1.82.0.#![feature(raw_ref_op)]//// Stable since Rust 1.83.0.#![feature(const_maybe_uninit_as_mut_ptr)]#![feature(const_mut_refs)]#![feature(const_option)]#![feature(const_ptr_write)]#![feature(const_refs_to_cell)]//// Expected to become stable.#![feature(arbitrary_self_types)]//// To be determined.#![feature(used_with_arg)]//// `feature(derive_coerce_pointee)` is expected to become stable. Before Rust// 1.84.0, it did not exist, so enable the predecessor features.#![cfg_attr(CONFIG_RUSTC_HAS_COERCE_POINTEE, feature(derive_coerce_pointee))]#![cfg_attr(not(CONFIG_RUSTC_HAS_COERCE_POINTEE), feature(coerce_unsized))]#![cfg_attr(not(CONFIG_RUSTC_HAS_COERCE_POINTEE), feature(dispatch_from_dyn))]#![cfg_attr(not(CONFIG_RUSTC_HAS_COERCE_POINTEE), feature(unsize))]//// `feature(file_with_nul)` is expected to become stable. Before Rust 1.89.0, it did not exist, so// enable it conditionally.#![cfg_attr(CONFIG_RUSTC_HAS_FILE_WITH_NUL, feature(file_with_nul))] // Ensure conditional compilation based on the kernel configuration works;// otherwise we may silently break things like initcall handling.#[cfg(not(CONFIG_RUST))]compile_error!("Missing kernel configuration for conditional compilation"); // Allow proc-macros to refer to `::kernel` inside the `kernel` crate (this crate).extern crate self as kernel; pub use ffi; pub mod acpi;pub mod alloc;#[cfg(CONFIG_AUXILIARY_BUS)]pub mod auxiliary;pub mod bitmap;pub mod bits;#[cfg(CONFIG_BLOCK)]pub mod block;pub mod bug;#[doc(hidden)]pub mod build_assert;pub mod clk;#[cfg(CONFIG_CONFIGFS_FS)]pub mod configfs;pub mod cpu;#[cfg(CONFIG_CPU_FREQ)]pub mod cpufreq;pub mod cpumask;pub mod cred;pub mod debugfs;pub mod device;pub mod device_id;pub mod devres;pub mod dma;pub mod driver;#[cfg(CONFIG_DRM = "y")]pub mod drm;pub mod error;pub mod faux;#[cfg(CONFIG_RUST_FW_LOADER_ABSTRACTIONS)]pub mod firmware;pub mod fmt;pub mod fs;pub mod id_pool;pub mod init;pub mod io;pub mod ioctl;pub mod iov;pub mod irq;pub mod jump_label;#[cfg(CONFIG_KUNIT)]pub mod kunit;pub mod list;pub mod maple_tree;pub mod miscdevice;pub mod mm;#[cfg(CONFIG_NET)]pub mod net;pub mod of;#[cfg(CONFIG_PM_OPP)]pub mod opp;pub mod page;#[cfg(CONFIG_PCI)]pub mod pci;pub mod pid_namespace;pub mod platform;pub mod prelude;pub mod print;pub mod processor;pub mod ptr;pub mod rbtree;pub mod regulator;pub mod revocable;pub mod scatterlist;pub mod security;pub mod seq_file;pub mod sizes;mod static_assert;#[doc(hidden)]pub mod std_vendor;pub mod str;pub mod sync;pub mod task;pub mod time;pub mod tracepoint;pub mod transmute;pub mod types;pub mod uaccess;pub mod workqueue;pub mod xarray; #[doc(hidden)]pub use bindings;pub use macros;pub use uapi; /// Prefix to appear before log messages printed from within the `kernel` crate.const __LOG_PREFIX: &[u8] = b"rust_kernel\0"; /// The top level entrypoint to implementing a kernel module.////// For any teardown or cleanup operations, your type may implement [`Drop`].pub trait Module: Sized + Sync + Send {    /// Called at module initialization time.    ///    /// Use this method to perform whatever setup or registration your module    /// should do.    ///    /// Equivalent to the `module_init` macro in the C API.    fn init(module: &'static ThisModule) -> error::Result<Self>;} /// A module that is pinned and initialised in-place.pub trait InPlaceModule: Sync + Send {    /// Creates an initialiser for the module.    ///    /// It is called when the module is loaded.    fn init(module: &'static ThisModule) -> impl pin_init::PinInit<Self, error::Error>;} impl<T: Module> InPlaceModule for T {    fn init(module: &'static ThisModule) -> impl pin_init::PinInit<Self, error::Error> {        let initer = move |slot: *mut Self| {            let m = <Self as Module>::init(module)?;             // SAFETY: `slot` is valid for write per the contract with `pin_init_from_closure`.            unsafe { slot.write(m) };            Ok(())        };         // SAFETY: On success, `initer` always fully initialises an instance of `Self`.        unsafe { pin_init::pin_init_from_closure(initer) }    }} /// Metadata attached to a [`Module`] or [`InPlaceModule`].pub trait ModuleMetadata {    /// The name of the module as specified in the `module!` macro.    const NAME: &'static crate::str::CStr;} /// Equivalent to `THIS_MODULE` in the C API.////// C header: [`include/linux/init.h`](srctree/include/linux/init.h)pub struct ThisModule(*mut bindings::module); // SAFETY: `THIS_MODULE` may be used from all threads within a module.unsafe impl Sync for ThisModule {} impl ThisModule {    /// Creates a [`ThisModule`] given the `THIS_MODULE` pointer.    ///    /// # Safety    ///    /// The pointer must be equal to the right `THIS_MODULE`.    pub const unsafe fn from_ptr(ptr: *mut bindings::module) -> ThisModule {        ThisModule(ptr)    }     /// Access the raw pointer for this module.    ///    /// It is up to the user to use it correctly.    pub const fn as_ptr(&self) -> *mut bindings::module {        self.0    }} #[cfg(not(testlib))]#[panic_handler]fn panic(info: &core::panic::PanicInfo<'_>) -> ! {    pr_emerg!("{}\n", info);    // SAFETY: FFI call.    unsafe { bindings::BUG() };} /// Produces a pointer to an object from a pointer to one of its fields.////// If you encounter a type mismatch due to the [`Opaque`] type, then use [`Opaque::cast_into`] or/// [`Opaque::cast_from`] to resolve the mismatch.////// [`Opaque`]: crate::types::Opaque/// [`Opaque::cast_into`]: crate::types::Opaque::cast_into/// [`Opaque::cast_from`]: crate::types::Opaque::cast_from////// # Safety////// The pointer passed to this macro, and the pointer returned by this macro, must both be in/// bounds of the same allocation.////// # Examples////// ```/// # use kernel::container_of;/// struct Test {///     a: u64,///     b: u32,/// }////// let test = Test { a: 10, b: 20 };/// let b_ptr: *const _ = &test.b;/// // SAFETY: The pointer points at the `b` field of a `Test`, so the resulting pointer will be/// // in-bounds of the same allocation as `b_ptr`./// let test_alias = unsafe { container_of!(b_ptr, Test, b) };/// assert!(core::ptr::eq(&test, test_alias));/// ```#[macro_export]macro_rules! container_of {    ($field_ptr:expr, $Container:ty, $($fields:tt)*) => {{        let offset: usize = ::core::mem::offset_of!($Container, $($fields)*);        let field_ptr = $field_ptr;        let container_ptr = field_ptr.byte_sub(offset).cast::<$Container>();        $crate::assert_same_type(field_ptr, (&raw const (*container_ptr).$($fields)*).cast_mut());        container_ptr    }}} /// Helper for [`container_of!`].#[doc(hidden)]pub fn assert_same_type<T>(_: T, _: T) {} /// Helper for `.rs.S` files.#[doc(hidden)]#[macro_export]macro_rules! concat_literals {    ($( $asm:literal )* ) => {        ::core::concat!($($asm),*)    };} /// Wrapper around `asm!` configured for use in the kernel.////// Uses a semicolon to avoid parsing ambiguities, even though this does not match native `asm!`/// syntax.// For x86, `asm!` uses intel syntax by default, but we want to use at&t syntax in the kernel.#[cfg(any(target_arch = "x86", target_arch = "x86_64"))]#[macro_export]macro_rules! asm {    ($($asm:expr),* ; $($rest:tt)*) => {        ::core::arch::asm!( $($asm)*, options(att_syntax), $($rest)* )    };} /// Wrapper around `asm!` configured for use in the kernel.////// Uses a semicolon to avoid parsing ambiguities, even though this does not match native `asm!`/// syntax.// For non-x86 arches we just pass through to `asm!`.#[cfg(not(any(target_arch = "x86", target_arch = "x86_64")))]#[macro_export]macro_rules! asm {    ($($asm:expr),* ; $($rest:tt)*) => {        ::core::arch::asm!( $($asm)*, $($rest)* )    };} /// Gets the C string file name of a [`Location`].////// If `Location::file_as_c_str()` is not available, returns a string that warns about it.////// [`Location`]: core::panic::Location////// # Examples////// ```/// # use kernel::file_from_location;////// #[track_caller]/// fn foo() {///     let caller = core::panic::Location::caller();//////     // Output:///     // - A path like "rust/kernel/example.rs" if `file_as_c_str()` is available.///     // - "<Location::file_as_c_str() not supported>" otherwise.///     let caller_file = file_from_location(caller);//////     // Prints out the message with caller's file name.///     pr_info!("foo() called in file {caller_file:?}\n");//////     # if cfg!(CONFIG_RUSTC_HAS_FILE_WITH_NUL) {///     #     assert_eq!(Ok(caller.file()), caller_file.to_str());///     # }/// }////// # foo();/// ```#[inline]pub fn file_from_location<'a>(loc: &'a core::panic::Location<'a>) -> &'a core::ffi::CStr {    #[cfg(CONFIG_RUSTC_HAS_FILE_AS_C_STR)]    {        loc.file_as_c_str()    }     #[cfg(all(CONFIG_RUSTC_HAS_FILE_WITH_NUL, not(CONFIG_RUSTC_HAS_FILE_AS_C_STR)))]    {        loc.file_with_nul()    }     #[cfg(not(CONFIG_RUSTC_HAS_FILE_WITH_NUL))]    {        let _ = loc;        c"<Location::file_as_c_str() not supported>"    }}