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// SPDX-License-Identifier: GPL-2.0 //! Crate for all kernel procedural macros. // When fixdep scans this, it will find this string `CONFIG_RUSTC_VERSION_TEXT`// and thus add a dependency on `include/config/RUSTC_VERSION_TEXT`, which is// touched by Kconfig when the version string from the compiler changes. #[macro_use]mod quote;mod concat_idents;mod helpers;mod module;mod paste;mod pin_data;mod pinned_drop;mod vtable;mod zeroable; use proc_macro::TokenStream; /// Declares a kernel module.////// The `type` argument should be a type which implements the [`Module`]/// trait. Also accepts various forms of kernel metadata.////// C header: [`include/linux/moduleparam.h`](srctree/include/linux/moduleparam.h)////// [`Module`]: ../kernel/trait.Module.html////// # Examples////// ```/// use kernel::prelude::*;////// module!{///     type: MyModule,///     name: "my_kernel_module",///     author: "Rust for Linux Contributors",///     description: "My very own kernel module!",///     license: "GPL",///     alias: ["alternate_module_name"],/// }////// struct MyModule(i32);////// impl kernel::Module for MyModule {///     fn init(_module: &'static ThisModule) -> Result<Self> {///         let foo: i32 = 42;///         pr_info!("I contain:  {}\n", foo);///         Ok(Self(foo))///     }/// }/// # fn main() {}/// ```////// ## Firmware////// The following example shows how to declare a kernel module that needs/// to load binary firmware files. You need to specify the file names of/// the firmware in the `firmware` field. The information is embedded/// in the `modinfo` section of the kernel module. For example, a tool to/// build an initramfs uses this information to put the firmware files into/// the initramfs image.////// ```/// use kernel::prelude::*;////// module!{///     type: MyDeviceDriverModule,///     name: "my_device_driver_module",///     author: "Rust for Linux Contributors",///     description: "My device driver requires firmware",///     license: "GPL",///     firmware: ["my_device_firmware1.bin", "my_device_firmware2.bin"],/// }////// struct MyDeviceDriverModule;////// impl kernel::Module for MyDeviceDriverModule {///     fn init(_module: &'static ThisModule) -> Result<Self> {///         Ok(Self)///     }/// }/// # fn main() {}/// ```////// # Supported argument types///   - `type`: type which implements the [`Module`] trait (required).///   - `name`: ASCII string literal of the name of the kernel module (required).///   - `author`: string literal of the author of the kernel module.///   - `description`: string literal of the description of the kernel module.///   - `license`: ASCII string literal of the license of the kernel module (required).///   - `alias`: array of ASCII string literals of the alias names of the kernel module.///   - `firmware`: array of ASCII string literals of the firmware files of///     the kernel module.#[proc_macro]pub fn module(ts: TokenStream) -> TokenStream {    module::module(ts)} /// Declares or implements a vtable trait.////// Linux's use of pure vtables is very close to Rust traits, but they differ/// in how unimplemented functions are represented. In Rust, traits can provide/// default implementation for all non-required methods (and the default/// implementation could just return `Error::EINVAL`); Linux typically use C/// `NULL` pointers to represent these functions.////// This attribute closes that gap. A trait can be annotated with the/// `#[vtable]` attribute. Implementers of the trait will then also have to/// annotate the trait with `#[vtable]`. This attribute generates a `HAS_*`/// associated constant bool for each method in the trait that is set to true if/// the implementer has overridden the associated method.////// For a trait method to be optional, it must have a default implementation./// This is also the case for traits annotated with `#[vtable]`, but in this/// case the default implementation will never be executed. The reason for this/// is that the functions will be called through function pointers installed in/// C side vtables. When an optional method is not implemented on a `#[vtable]`/// trait, a NULL entry is installed in the vtable. Thus the default/// implementation is never called. Since these traits are not designed to be/// used on the Rust side, it should not be possible to call the default/// implementation. This is done to ensure that we call the vtable methods/// through the C vtable, and not through the Rust vtable. Therefore, the/// default implementation should call `kernel::build_error`, which prevents/// calls to this function at compile time:////// ```compile_fail/// # // Intentionally missing `use`s to simplify `rusttest`./// kernel::build_error(VTABLE_DEFAULT_ERROR)/// ```////// Note that you might need to import [`kernel::error::VTABLE_DEFAULT_ERROR`].////// This macro should not be used when all functions are required.////// # Examples////// ```/// use kernel::error::VTABLE_DEFAULT_ERROR;/// use kernel::prelude::*;////// // Declares a `#[vtable]` trait/// #[vtable]/// pub trait Operations: Send + Sync + Sized {///     fn foo(&self) -> Result<()> {///         kernel::build_error(VTABLE_DEFAULT_ERROR)///     }//////     fn bar(&self) -> Result<()> {///         kernel::build_error(VTABLE_DEFAULT_ERROR)///     }/// }////// struct Foo;////// // Implements the `#[vtable]` trait/// #[vtable]/// impl Operations for Foo {///     fn foo(&self) -> Result<()> {/// #        Err(EINVAL)///         // ...///     }/// }////// assert_eq!(<Foo as Operations>::HAS_FOO, true);/// assert_eq!(<Foo as Operations>::HAS_BAR, false);/// ```////// [`kernel::error::VTABLE_DEFAULT_ERROR`]: ../kernel/error/constant.VTABLE_DEFAULT_ERROR.html#[proc_macro_attribute]pub fn vtable(attr: TokenStream, ts: TokenStream) -> TokenStream {    vtable::vtable(attr, ts)} /// Concatenate two identifiers.////// This is useful in macros that need to declare or reference items with names/// starting with a fixed prefix and ending in a user specified name. The resulting/// identifier has the span of the second argument.////// # Examples////// ```/// # const binder_driver_return_protocol_BR_OK: u32 = 0;/// # const binder_driver_return_protocol_BR_ERROR: u32 = 1;/// # const binder_driver_return_protocol_BR_TRANSACTION: u32 = 2;/// # const binder_driver_return_protocol_BR_REPLY: u32 = 3;/// # const binder_driver_return_protocol_BR_DEAD_REPLY: u32 = 4;/// # const binder_driver_return_protocol_BR_TRANSACTION_COMPLETE: u32 = 5;/// # const binder_driver_return_protocol_BR_INCREFS: u32 = 6;/// # const binder_driver_return_protocol_BR_ACQUIRE: u32 = 7;/// # const binder_driver_return_protocol_BR_RELEASE: u32 = 8;/// # const binder_driver_return_protocol_BR_DECREFS: u32 = 9;/// # const binder_driver_return_protocol_BR_NOOP: u32 = 10;/// # const binder_driver_return_protocol_BR_SPAWN_LOOPER: u32 = 11;/// # const binder_driver_return_protocol_BR_DEAD_BINDER: u32 = 12;/// # const binder_driver_return_protocol_BR_CLEAR_DEATH_NOTIFICATION_DONE: u32 = 13;/// # const binder_driver_return_protocol_BR_FAILED_REPLY: u32 = 14;/// use kernel::macros::concat_idents;////// macro_rules! pub_no_prefix {///     ($prefix:ident, $($newname:ident),+) => {///         $(pub(crate) const $newname: u32 = concat_idents!($prefix, $newname);)+///     };/// }////// pub_no_prefix!(///     binder_driver_return_protocol_,///     BR_OK,///     BR_ERROR,///     BR_TRANSACTION,///     BR_REPLY,///     BR_DEAD_REPLY,///     BR_TRANSACTION_COMPLETE,///     BR_INCREFS,///     BR_ACQUIRE,///     BR_RELEASE,///     BR_DECREFS,///     BR_NOOP,///     BR_SPAWN_LOOPER,///     BR_DEAD_BINDER,///     BR_CLEAR_DEATH_NOTIFICATION_DONE,///     BR_FAILED_REPLY/// );////// assert_eq!(BR_OK, binder_driver_return_protocol_BR_OK);/// ```#[proc_macro]pub fn concat_idents(ts: TokenStream) -> TokenStream {    concat_idents::concat_idents(ts)} /// Used to specify the pinning information of the fields of a struct.////// This is somewhat similar in purpose as/// [pin-project-lite](https://crates.io/crates/pin-project-lite)./// Place this macro on a struct definition and then `#[pin]` in front of the attributes of each/// field you want to structurally pin.////// This macro enables the use of the [`pin_init!`] macro. When pin-initializing a `struct`,/// then `#[pin]` directs the type of initializer that is required.////// If your `struct` implements `Drop`, then you need to add `PinnedDrop` as arguments to this/// macro, and change your `Drop` implementation to `PinnedDrop` annotated with/// `#[`[`macro@pinned_drop`]`]`, since dropping pinned values requires extra care.////// # Examples////// ```/// # #![feature(lint_reasons)]/// # use kernel::prelude::*;/// # use std::{sync::Mutex, process::Command};/// # use kernel::macros::pin_data;/// #[pin_data]/// struct DriverData {///     #[pin]///     queue: Mutex<KVec<Command>>,///     buf: KBox<[u8; 1024 * 1024]>,/// }/// ```////// ```/// # #![feature(lint_reasons)]/// # use kernel::prelude::*;/// # use std::{sync::Mutex, process::Command};/// # use core::pin::Pin;/// # pub struct Info;/// # mod bindings {/// #     pub unsafe fn destroy_info(_ptr: *mut super::Info) {}/// # }/// use kernel::macros::{pin_data, pinned_drop};////// #[pin_data(PinnedDrop)]/// struct DriverData {///     #[pin]///     queue: Mutex<KVec<Command>>,///     buf: KBox<[u8; 1024 * 1024]>,///     raw_info: *mut Info,/// }////// #[pinned_drop]/// impl PinnedDrop for DriverData {///     fn drop(self: Pin<&mut Self>) {///         unsafe { bindings::destroy_info(self.raw_info) };///     }/// }/// # fn main() {}/// ```////// [`pin_init!`]: ../kernel/macro.pin_init.html//  ^ cannot use direct link, since `kernel` is not a dependency of `macros`.#[proc_macro_attribute]pub fn pin_data(inner: TokenStream, item: TokenStream) -> TokenStream {    pin_data::pin_data(inner, item)} /// Used to implement `PinnedDrop` safely.////// Only works on structs that are annotated via `#[`[`macro@pin_data`]`]`.////// # Examples////// ```/// # #![feature(lint_reasons)]/// # use kernel::prelude::*;/// # use macros::{pin_data, pinned_drop};/// # use std::{sync::Mutex, process::Command};/// # use core::pin::Pin;/// # mod bindings {/// #     pub struct Info;/// #     pub unsafe fn destroy_info(_ptr: *mut Info) {}/// # }/// #[pin_data(PinnedDrop)]/// struct DriverData {///     #[pin]///     queue: Mutex<KVec<Command>>,///     buf: KBox<[u8; 1024 * 1024]>,///     raw_info: *mut bindings::Info,/// }////// #[pinned_drop]/// impl PinnedDrop for DriverData {///     fn drop(self: Pin<&mut Self>) {///         unsafe { bindings::destroy_info(self.raw_info) };///     }/// }/// ```#[proc_macro_attribute]pub fn pinned_drop(args: TokenStream, input: TokenStream) -> TokenStream {    pinned_drop::pinned_drop(args, input)} /// Paste identifiers together.////// Within the `paste!` macro, identifiers inside `[<` and `>]` are concatenated together to form a/// single identifier.////// This is similar to the [`paste`] crate, but with pasting feature limited to identifiers and/// literals (lifetimes and documentation strings are not supported). There is a difference in/// supported modifiers as well.////// # Example////// ```/// # const binder_driver_return_protocol_BR_OK: u32 = 0;/// # const binder_driver_return_protocol_BR_ERROR: u32 = 1;/// # const binder_driver_return_protocol_BR_TRANSACTION: u32 = 2;/// # const binder_driver_return_protocol_BR_REPLY: u32 = 3;/// # const binder_driver_return_protocol_BR_DEAD_REPLY: u32 = 4;/// # const binder_driver_return_protocol_BR_TRANSACTION_COMPLETE: u32 = 5;/// # const binder_driver_return_protocol_BR_INCREFS: u32 = 6;/// # const binder_driver_return_protocol_BR_ACQUIRE: u32 = 7;/// # const binder_driver_return_protocol_BR_RELEASE: u32 = 8;/// # const binder_driver_return_protocol_BR_DECREFS: u32 = 9;/// # const binder_driver_return_protocol_BR_NOOP: u32 = 10;/// # const binder_driver_return_protocol_BR_SPAWN_LOOPER: u32 = 11;/// # const binder_driver_return_protocol_BR_DEAD_BINDER: u32 = 12;/// # const binder_driver_return_protocol_BR_CLEAR_DEATH_NOTIFICATION_DONE: u32 = 13;/// # const binder_driver_return_protocol_BR_FAILED_REPLY: u32 = 14;/// macro_rules! pub_no_prefix {///     ($prefix:ident, $($newname:ident),+) => {///         kernel::macros::paste! {///             $(pub(crate) const $newname: u32 = [<$prefix $newname>];)+///         }///     };/// }////// pub_no_prefix!(///     binder_driver_return_protocol_,///     BR_OK,///     BR_ERROR,///     BR_TRANSACTION,///     BR_REPLY,///     BR_DEAD_REPLY,///     BR_TRANSACTION_COMPLETE,///     BR_INCREFS,///     BR_ACQUIRE,///     BR_RELEASE,///     BR_DECREFS,///     BR_NOOP,///     BR_SPAWN_LOOPER,///     BR_DEAD_BINDER,///     BR_CLEAR_DEATH_NOTIFICATION_DONE,///     BR_FAILED_REPLY/// );////// assert_eq!(BR_OK, binder_driver_return_protocol_BR_OK);/// ```////// # Modifiers////// For each identifier, it is possible to attach one or multiple modifiers to/// it.////// Currently supported modifiers are:/// * `span`: change the span of concatenated identifier to the span of the specified token. By///   default the span of the `[< >]` group is used./// * `lower`: change the identifier to lower case./// * `upper`: change the identifier to upper case.////// ```/// # const binder_driver_return_protocol_BR_OK: u32 = 0;/// # const binder_driver_return_protocol_BR_ERROR: u32 = 1;/// # const binder_driver_return_protocol_BR_TRANSACTION: u32 = 2;/// # const binder_driver_return_protocol_BR_REPLY: u32 = 3;/// # const binder_driver_return_protocol_BR_DEAD_REPLY: u32 = 4;/// # const binder_driver_return_protocol_BR_TRANSACTION_COMPLETE: u32 = 5;/// # const binder_driver_return_protocol_BR_INCREFS: u32 = 6;/// # const binder_driver_return_protocol_BR_ACQUIRE: u32 = 7;/// # const binder_driver_return_protocol_BR_RELEASE: u32 = 8;/// # const binder_driver_return_protocol_BR_DECREFS: u32 = 9;/// # const binder_driver_return_protocol_BR_NOOP: u32 = 10;/// # const binder_driver_return_protocol_BR_SPAWN_LOOPER: u32 = 11;/// # const binder_driver_return_protocol_BR_DEAD_BINDER: u32 = 12;/// # const binder_driver_return_protocol_BR_CLEAR_DEATH_NOTIFICATION_DONE: u32 = 13;/// # const binder_driver_return_protocol_BR_FAILED_REPLY: u32 = 14;/// macro_rules! pub_no_prefix {///     ($prefix:ident, $($newname:ident),+) => {///         kernel::macros::paste! {///             $(pub(crate) const fn [<$newname:lower:span>]() -> u32 { [<$prefix $newname:span>] })+///         }///     };/// }////// pub_no_prefix!(///     binder_driver_return_protocol_,///     BR_OK,///     BR_ERROR,///     BR_TRANSACTION,///     BR_REPLY,///     BR_DEAD_REPLY,///     BR_TRANSACTION_COMPLETE,///     BR_INCREFS,///     BR_ACQUIRE,///     BR_RELEASE,///     BR_DECREFS,///     BR_NOOP,///     BR_SPAWN_LOOPER,///     BR_DEAD_BINDER,///     BR_CLEAR_DEATH_NOTIFICATION_DONE,///     BR_FAILED_REPLY/// );////// assert_eq!(br_ok(), binder_driver_return_protocol_BR_OK);/// ```////// # Literals////// Literals can also be concatenated with other identifiers:////// ```/// macro_rules! create_numbered_fn {///     ($name:literal, $val:literal) => {///         kernel::macros::paste! {///             fn [<some_ $name _fn $val>]() -> u32 { $val }///         }///     };/// }////// create_numbered_fn!("foo", 100);////// assert_eq!(some_foo_fn100(), 100)/// ```////// [`paste`]: https://docs.rs/paste/#[proc_macro]pub fn paste(input: TokenStream) -> TokenStream {    let mut tokens = input.into_iter().collect();    paste::expand(&mut tokens);    tokens.into_iter().collect()} /// Derives the [`Zeroable`] trait for the given struct.////// This can only be used for structs where every field implements the [`Zeroable`] trait.////// # Examples////// ```/// use kernel::macros::Zeroable;////// #[derive(Zeroable)]/// pub struct DriverData {///     id: i64,///     buf_ptr: *mut u8,///     len: usize,/// }/// ```#[proc_macro_derive(Zeroable)]pub fn derive_zeroable(input: TokenStream) -> TokenStream {    zeroable::derive(input)}