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+// 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 1.80.0.
+#![feature(slice_flatten)]
+//
+// 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;
+#[cfg(CONFIG_I2C = "y")]
+pub mod i2c;
+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;
+pub mod module_param;
+#[cfg(CONFIG_NET)]
+pub mod net;
+pub mod num;
+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;
+#[cfg(CONFIG_RUST_PWM_ABSTRACTIONS)]
+pub mod pwm;
+pub mod rbtree;
+pub mod regulator;
+pub mod revocable;
+pub mod scatterlist;
+pub mod security;
+pub mod seq_file;
+pub mod sizes;
+pub mod slice;
+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;
+#[cfg(CONFIG_USB = "y")]
+pub mod usb;
+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>"
+ }
+}