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authorLinus Torvalds <torvalds@linux-foundation.org>2026-08-30 09:22:00 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2026-08-30 09:22:00 -0700
commit034dd340b08be1f2f0477ad16131d609f9dbd53c (patch)
tree2536f4b2d7893ccd916b5abdf3c454ad6edc03c2 /rust/macros/lib.rs
downloadlinux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.tar.gz
linux-stable-034dd340b08be1f2f0477ad16131d609f9dbd53c.zip
Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted
Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure
Diffstat (limited to 'rust/macros/lib.rs')
-rw-r--r--rust/macros/lib.rs539
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diff --git a/rust/macros/lib.rs b/rust/macros/lib.rs
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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.
+
+// Stable since Rust 1.87.0.
+#![feature(extract_if)]
+//
+// Stable since Rust 1.88.0 under a different name, `proc_macro_span_file`,
+// which was added in Rust 1.88.0. This is why `cfg_attr` is used here, i.e.
+// to avoid depending on the full `proc_macro_span` on Rust >= 1.88.0.
+#![cfg_attr(not(CONFIG_RUSTC_HAS_SPAN_FILE), feature(proc_macro_span))]
+
+mod concat_idents;
+mod export;
+mod fmt;
+mod for_lt;
+mod helpers;
+mod kunit;
+mod module;
+mod paste;
+mod vtable;
+
+use proc_macro::TokenStream;
+
+use syn::parse_macro_input;
+
+/// Declares a kernel module.
+///
+/// The `type` argument should be a type which implements the [`Module`]
+/// trait. Also accepts various forms of kernel metadata.
+///
+/// The `params` field describe module parameters. Each entry has the form
+///
+/// ```ignore
+/// parameter_name: type {
+/// default: default_value,
+/// description: "Description",
+/// }
+/// ```
+///
+/// `type` may be one of
+///
+/// - [`i8`]
+/// - [`u8`]
+/// - [`i8`]
+/// - [`u8`]
+/// - [`i16`]
+/// - [`u16`]
+/// - [`i32`]
+/// - [`u32`]
+/// - [`i64`]
+/// - [`u64`]
+/// - [`isize`]
+/// - [`usize`]
+/// - [`bool`]
+///
+/// C header: [`include/linux/moduleparam.h`](srctree/include/linux/moduleparam.h)
+///
+/// [`Module`]: ../kernel/trait.Module.html
+///
+/// # Examples
+///
+/// ```ignore
+/// use kernel::prelude::*;
+///
+/// module!{
+/// type: MyModule,
+/// name: "my_kernel_module",
+/// authors: ["Rust for Linux Contributors"],
+/// description: "My very own kernel module!",
+/// license: "GPL",
+/// alias: ["alternate_module_name"],
+/// params: {
+/// my_parameter: i64 {
+/// default: 1,
+/// description: "This parameter has a default of 1",
+/// },
+/// },
+/// }
+///
+/// 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);
+/// pr_info!("i32 param is: {}\n", module_parameters::my_parameter.read());
+/// 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",
+/// authors: ["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).
+/// - `authors`: array of ASCII string literals of the authors 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(input: TokenStream) -> TokenStream {
+ module::module(parse_macro_input!(input))
+ .unwrap_or_else(|e| e.into_compile_error())
+ .into()
+}
+
+/// 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 `build_error!`, which prevents
+/// calls to this function at compile time:
+///
+/// ```compile_fail
+/// # // Intentionally missing `use`s to simplify `rusttest`.
+/// 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.
+///
+/// Additionally, this macro automatically handles the `OwnerModule`
+/// associated type: on the trait side, `type OwnerModule: ModuleMetadata;`
+/// is added as a required associated type if not already defined; on the
+/// impl side, `type OwnerModule = LocalModule;` is automatically inserted
+/// if not explicitly defined.
+///
+/// # Examples
+///
+/// ```
+/// use kernel::error::VTABLE_DEFAULT_ERROR;
+/// use kernel::prelude::*;
+///
+/// # struct LocalModule;
+/// # impl kernel::ModuleMetadata for LocalModule {
+/// # const NAME: &'static kernel::str::CStr = c"vtable_doctest";
+/// #
+/// # // SAFETY: This doctest runs on the host: there is no `THIS_MODULE`.
+/// # const THIS_MODULE: kernel::ThisModule = unsafe {
+/// # kernel::ThisModule::from_ptr(core::ptr::null_mut())
+/// # };
+/// # }
+/// #
+/// # fn main() {
+/// // Declares a `#[vtable]` trait
+/// #[vtable]
+/// pub trait Operations: Send + Sync + Sized {
+/// fn foo(&self) -> Result<()> {
+/// build_error!(VTABLE_DEFAULT_ERROR)
+/// }
+///
+/// fn bar(&self) -> Result<()> {
+/// 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, input: TokenStream) -> TokenStream {
+ parse_macro_input!(attr as syn::parse::Nothing);
+ vtable::vtable(parse_macro_input!(input))
+ .unwrap_or_else(|e| e.into_compile_error())
+ .into()
+}
+
+/// Export a function so that C code can call it via a header file.
+///
+/// Functions exported using this macro can be called from C code using the declaration in the
+/// appropriate header file. It should only be used in cases where C calls the function through a
+/// header file; cases where C calls into Rust via a function pointer in a vtable (such as
+/// `file_operations`) should not use this macro.
+///
+/// This macro has the following effect:
+///
+/// * Disables name mangling for this function.
+/// * Verifies at compile-time that the function signature matches the declaration in the header
+/// file.
+///
+/// You must declare the signature of the Rust function in a header file that is included by
+/// `rust/bindings/bindings_helper.h`.
+///
+/// This macro is *not* the same as the C macros `EXPORT_SYMBOL_*`. All Rust symbols are currently
+/// automatically exported with `EXPORT_SYMBOL_GPL`.
+#[proc_macro_attribute]
+pub fn export(attr: TokenStream, input: TokenStream) -> TokenStream {
+ parse_macro_input!(attr as syn::parse::Nothing);
+ export::export(parse_macro_input!(input)).into()
+}
+
+/// Like [`core::format_args!`], but automatically wraps arguments in [`kernel::fmt::Adapter`].
+///
+/// This macro allows generating `fmt::Arguments` while ensuring that each argument is wrapped with
+/// `::kernel::fmt::Adapter`, which customizes formatting behavior for kernel logging.
+///
+/// Named arguments used in the format string (e.g. `{foo}`) are detected and resolved from local
+/// bindings. All positional and named arguments are automatically wrapped.
+///
+/// This macro is an implementation detail of other kernel logging macros like [`pr_info!`] and
+/// should not typically be used directly.
+///
+/// [`kernel::fmt::Adapter`]: ../kernel/fmt/struct.Adapter.html
+/// [`pr_info!`]: ../kernel/macro.pr_info.html
+#[proc_macro]
+pub fn fmt(input: TokenStream) -> TokenStream {
+ fmt::fmt(input.into()).into()
+}
+
+/// 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(input: TokenStream) -> TokenStream {
+ concat_idents::concat_idents(parse_macro_input!(input)).into()
+}
+
+/// 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.
+///
+/// # 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;
+/// 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 = proc_macro2::TokenStream::from(input).into_iter().collect();
+ paste::expand(&mut tokens);
+ tokens
+ .into_iter()
+ .collect::<proc_macro2::TokenStream>()
+ .into()
+}
+
+/// Registers a KUnit test suite and its test cases using a user-space like syntax.
+///
+/// This macro should be used on modules. If `CONFIG_KUNIT` (in `.config`) is `n`, the target module
+/// is ignored.
+///
+/// # Examples
+///
+/// ```ignore
+/// # use kernel::prelude::*;
+/// #[kunit_tests(kunit_test_suit_name)]
+/// mod tests {
+/// #[test]
+/// fn foo() {
+/// assert_eq!(1, 1);
+/// }
+///
+/// #[test]
+/// fn bar() {
+/// assert_eq!(2, 2);
+/// }
+/// }
+/// ```
+#[proc_macro_attribute]
+pub fn kunit_tests(attr: TokenStream, input: TokenStream) -> TokenStream {
+ kunit::kunit_tests(parse_macro_input!(attr), parse_macro_input!(input))
+ .unwrap_or_else(|e| e.into_compile_error())
+ .into()
+}
+
+/// Obtain a type that implements [`ForLt`] for the given higher-ranked type.
+///
+/// Please refer to the documentation of the [`ForLt`] trait.
+///
+/// [`ForLt`]: trait.ForLt.html
+#[proc_macro]
+#[allow(non_snake_case)]
+pub fn ForLt(input: TokenStream) -> TokenStream {
+ for_lt::for_lt(parse_macro_input!(input)).into()
+}
+
+/// Obtain a type that implements [`CovariantForLt`] (and [`ForLt`]) for the given higher-ranked
+/// type.
+///
+/// Unlike [`ForLt!`], this macro additionally proves that the type is covariant over the lifetime,
+/// providing a safe [`CovariantForLt::cast_ref`] method.
+///
+/// Please refer to the documentation of the [`CovariantForLt`] trait.
+///
+/// [`CovariantForLt`]: trait.CovariantForLt.html
+/// [`CovariantForLt::cast_ref`]: trait.CovariantForLt.html#method.cast_ref
+/// [`ForLt`]: trait.ForLt.html
+#[proc_macro]
+#[allow(non_snake_case)]
+pub fn CovariantForLt(input: TokenStream) -> TokenStream {
+ for_lt::covariant_for_lt(parse_macro_input!(input)).into()
+}