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2023-08-29Merge tag 'rust-6.6' of https://github.com/Rust-for-Linux/linuxLinus Torvalds
Pull rust updates from Miguel Ojeda: "In terms of lines, most changes this time are on the pinned-init API and infrastructure. While we have a Rust version upgrade, and thus a bunch of changes from the vendored 'alloc' crate as usual, this time those do not account for many lines. Toolchain and infrastructure: - Upgrade to Rust 1.71.1. This is the second such upgrade, which is a smaller jump compared to the last time. This version allows us to remove the '__rust_*' allocator functions -- the compiler now generates them as expected, thus now our 'KernelAllocator' is used. It also introduces the 'offset_of!' macro in the standard library (as an unstable feature) which we will need soon. So far, we were using a declarative macro as a prerequisite in some not-yet-landed patch series, which did not support sub-fields (i.e. nested structs): #[repr(C)] struct S { a: u16, b: (u8, u8), } assert_eq!(offset_of!(S, b.1), 3); - Upgrade to bindgen 0.65.1. This is the first time we upgrade its version. Given it is a fairly big jump, it comes with a fair number of improvements/changes that affect us, such as a fix needed to support LLVM 16 as well as proper support for '__noreturn' C functions, which are now mapped to return the '!' type in Rust: void __noreturn f(void); // C pub fn f() -> !; // Rust - 'scripts/rust_is_available.sh' improvements and fixes. This series takes care of all the issues known so far and adds a few new checks to cover for even more cases, plus adds some more help texts. All this together will hopefully make problematic setups easier to identify and to be solved by users building the kernel. In addition, it adds a test suite which covers all branches of the shell script, as well as tests for the issues found so far. - Support rust-analyzer for out-of-tree modules too. - Give 'cfg's to rust-analyzer for the 'core' and 'alloc' crates. - Drop 'scripts/is_rust_module.sh' since it is not needed anymore. Macros crate: - New 'paste!' proc macro. This macro is a more flexible version of 'concat_idents!': it allows the resulting identifier to be used to declare new items and it allows to transform the identifiers before concatenating them, e.g. let x_1 = 42; paste!(let [<x _2>] = [<x _1>];); assert!(x_1 == x_2); The macro is then used for several of the pinned-init API changes in this pull. Pinned-init API: - Make '#[pin_data]' compatible with conditional compilation of fields, allowing to write code like: #[pin_data] pub struct Foo { #[cfg(CONFIG_BAR)] a: Bar, #[cfg(not(CONFIG_BAR))] a: Baz, } - New '#[derive(Zeroable)]' proc macro for the 'Zeroable' trait, which allows 'unsafe' implementations for structs where every field implements the 'Zeroable' trait, e.g.: #[derive(Zeroable)] pub struct DriverData { id: i64, buf_ptr: *mut u8, len: usize, } - Add '..Zeroable::zeroed()' syntax to the 'pin_init!' macro for zeroing all other fields, e.g.: pin_init!(Buf { buf: [1; 64], ..Zeroable::zeroed() }); - New '{,pin_}init_array_from_fn()' functions to create array initializers given a generator function, e.g.: let b: Box<[usize; 1_000]> = Box::init::<Error>( init_array_from_fn(|i| i) ).unwrap(); assert_eq!(b.len(), 1_000); assert_eq!(b[123], 123); - New '{,pin_}chain' methods for '{,Pin}Init<T, E>' that allow to execute a closure on the value directly after initialization, e.g.: let foo = init!(Foo { buf <- init::zeroed() }).chain(|foo| { foo.setup(); Ok(()) }); - Support arbitrary paths in init macros, instead of just identifiers and generic types. - Implement the 'Zeroable' trait for the 'UnsafeCell<T>' and 'Opaque<T>' types. - Make initializer values inaccessible after initialization. - Make guards in the init macros hygienic. 'allocator' module: - Use 'krealloc_aligned()' in 'KernelAllocator::alloc' preventing misaligned allocations when the Rust 1.71.1 upgrade is applied later in this pull. The equivalent fix for the previous compiler version (where 'KernelAllocator' is not yet used) was merged into 6.5 already, which added the 'krealloc_aligned()' function used here. - Implement 'KernelAllocator::{realloc, alloc_zeroed}' for performance, using 'krealloc_aligned()' too, which forwards the call to the C API. 'types' module: - Make 'Opaque' be '!Unpin', removing the need to add a 'PhantomPinned' field to Rust structs that contain C structs which must not be moved. - Make 'Opaque' use 'UnsafeCell' as the outer type, rather than inner. Documentation: - Suggest obtaining the source code of the Rust's 'core' library using the tarball instead of the repository. MAINTAINERS: - Andreas and Alice, from Samsung and Google respectively, are joining as reviewers of the "RUST" entry. As well as a few other minor changes and cleanups" * tag 'rust-6.6' of https://github.com/Rust-for-Linux/linux: (42 commits) rust: init: update expanded macro explanation rust: init: add `{pin_}chain` functions to `{Pin}Init<T, E>` rust: init: make `PinInit<T, E>` a supertrait of `Init<T, E>` rust: init: implement `Zeroable` for `UnsafeCell<T>` and `Opaque<T>` rust: init: add support for arbitrary paths in init macros rust: init: add functions to create array initializers rust: init: add `..Zeroable::zeroed()` syntax for zeroing all missing fields rust: init: make initializer values inaccessible after initializing rust: init: wrap type checking struct initializers in a closure rust: init: make guards in the init macros hygienic rust: add derive macro for `Zeroable` rust: init: make `#[pin_data]` compatible with conditional compilation of fields rust: init: consolidate init macros docs: rust: clarify what 'rustup override' does docs: rust: update instructions for obtaining 'core' source docs: rust: add command line to rust-analyzer section scripts: generate_rust_analyzer: provide `cfg`s for `core` and `alloc` rust: bindgen: upgrade to 0.65.1 rust: enable `no_mangle_with_rust_abi` Clippy lint rust: upgrade to Rust 1.71.1 ...
2023-08-21rust: add derive macro for `Zeroable`Benno Lossin
Add a derive proc-macro for the `Zeroable` trait. The macro supports structs where every field implements the `Zeroable` trait. This way `unsafe` implementations can be avoided. The macro is split into two parts: - a proc-macro to parse generics into impl and ty generics, - a declarative macro that expands to the impl block. Suggested-by: Asahi Lina <lina@asahilina.net> Signed-off-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Gary Guo <gary@garyguo.net> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Link: https://lore.kernel.org/r/20230814084602.25699-4-benno.lossin@proton.me [ Added `ignore` to the `lib.rs` example and cleaned trivial nit. ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-08-10btf, scripts: rust: drop is_rust_module.shAndrea Righi
With commit c1177979af9c ("btf, scripts: Exclude Rust CUs with pahole") we are now able to use pahole directly to identify Rust compilation units (CUs) and exclude them from generating BTF debugging information (when DEBUG_INFO_BTF is enabled). And if pahole doesn't support the --lang-exclude flag, we can't enable both RUST and DEBUG_INFO_BTF at the same time. So, in any case, the script is_rust_module.sh is just redundant and we can drop it. NOTE: we may also be able to drop the "Rust loadable module" mark inside Rust modules, but it seems safer to keep it for now to make sure we are not breaking any external tool that may potentially rely on it. Signed-off-by: Andrea Righi <andrea.righi@canonical.com> Reviewed-by: Nathan Chancellor <nathan@kernel.org> Tested-by: Eric Curtin <ecurtin@redhat.com> Reviewed-by: Eric Curtin <ecurtin@redhat.com> Reviewed-by: Neal Gompa <neal@gompa.dev> Reviewed-by: Masahiro Yamada <masahiroy@kernel.org> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Acked-by: Daniel Xu <dxu@dxuuu.xyz> Link: https://lore.kernel.org/r/20230704052136.155445-1-andrea.righi@canonical.com [ Picked the `Reviewed-by`s from the old patch too. ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-08-10rust: macros: add `paste!` proc macroGary Guo
This macro provides a flexible way to concatenated identifiers together and it allows the resulting identifier to be used to declare new items, which `concat_idents!` does not allow. It also allows identifiers to be transformed before concatenated. The `concat_idents!` example let x_1 = 42; let x_2 = concat_idents!(x, _1); assert!(x_1 == x_2); can be written with `paste!` macro like this: let x_1 = 42; let x_2 = paste!([<x _1>]); assert!(x_1 == x_2); However `paste!` macro is more flexible because it can be used to create a new variable: let x_1 = 42; paste!(let [<x _2>] = [<x _1>];); assert!(x_1 == x_2); While this is not possible with `concat_idents!`. This macro is similar to the `paste!` crate [1], but this is a fresh implementation to avoid vendoring large amount of code directly. Also, I have augmented it to provide a way to specify span of the resulting token, allowing precise control. For example, this code is broken because the variable is declared inside the macro, so Rust macro hygiene rules prevents access from the outside: macro_rules! m { ($id: ident) => { // The resulting token has hygiene of the macro. paste!(let [<$id>] = 1;) } } m!(a); let _ = a; In this version of `paste!` macro I added a `span` modifier to allow this: macro_rules! m { ($id: ident) => { // The resulting token has hygiene of `$id`. paste!(let [<$id:span>] = 1;) } } m!(a); let _ = a; Link: http://docs.rs/paste/ [1] Signed-off-by: Gary Guo <gary@garyguo.net> Reviewed-by: Björn Roy Baron <bjorn3_gh@protonmail.com> Reviewed-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Link: https://lore.kernel.org/r/20230628171108.1150742-1-gary@garyguo.net [ Added SPDX license identifier as discussed in the list and fixed typo. ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-08-09rust: macros: vtable: fix `HAS_*` redefinition (`gen_const_name`)Qingsong Chen
If we define the same function name twice in a trait (using `#[cfg]`), the `vtable` macro will redefine its `gen_const_name`, e.g. this will define `HAS_BAR` twice: #[vtable] pub trait Foo { #[cfg(CONFIG_X)] fn bar(); #[cfg(not(CONFIG_X))] fn bar(x: usize); } Fixes: b44becc5ee80 ("rust: macros: add `#[vtable]` proc macro") Signed-off-by: Qingsong Chen <changxian.cqs@antgroup.com> Reviewed-by: Andreas Hindborg <a.hindborg@samsung.com> Reviewed-by: Gary Guo <gary@garyguo.net> Reviewed-by: Sergio González Collado <sergio.collado@gmail.com> Link: https://lore.kernel.org/r/20230808025404.2053471-1-changxian.cqs@antgroup.com Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-05-31rust: macros: replace Self with the concrete type in #[pin_data]Benno Lossin
When using `#[pin_data]` on a struct that used `Self` in the field types, a type error would be emitted when trying to use `pin_init!`. Since an internal type would be referenced by `Self` instead of the defined struct. This patch fixes this issue by replacing all occurrences of `Self` in the `#[pin_data]` macro with the concrete type circumventing the issue. Since rust allows type definitions inside of blocks, which are expressions, the macro also checks for these and emits a compile error when it finds `trait`, `enum`, `union`, `struct` or `impl`. These keywords allow creating new `Self` contexts, which conflicts with the current implementation of replacing every `Self` ident. If these were allowed, some `Self` idents would be replaced incorrectly. Signed-off-by: Benno Lossin <benno.lossin@proton.me> Reported-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Reviewed-by: Gary Guo <gary@garyguo.net> Link: https://lore.kernel.org/r/20230424081112.99890-3-benno.lossin@proton.me [ Added newline in commit message ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-05-31rust: macros: refactor generics parsing of `#[pin_data]` into its own functionBenno Lossin
Other macros might also want to parse generics. Additionally this makes the code easier to read, as the next commit will introduce more code in `#[pin_data]`. Also add more comments to explain how parsing generics work. Signed-off-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Gary Guo <gary@garyguo.net> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Link: https://lore.kernel.org/r/20230424081112.99890-2-benno.lossin@proton.me Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-05-31rust: macros: fix usage of `#[allow]` in `quote!`Benno Lossin
When using `quote!` as part of an expression that was not the last one in a function, the `#[allow(clippy::vec_init_then_push)]` attribute would be present on an expression, which is not allowed. This patch refactors that part of the macro to use a statement instead. Signed-off-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Reviewed-by: Gary Guo <gary@garyguo.net> Link: https://lore.kernel.org/r/20230424081112.99890-1-benno.lossin@proton.me Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-04-12rust: init: add `PinnedDrop` trait and macrosBenno Lossin
The `PinnedDrop` trait that facilitates destruction of pinned types. It has to be implemented via the `#[pinned_drop]` macro, since the `drop` function should not be called by normal code, only by other destructors. It also only works on structs that are annotated with `#[pin_data(PinnedDrop)]`. Co-developed-by: Gary Guo <gary@garyguo.net> Signed-off-by: Gary Guo <gary@garyguo.net> Signed-off-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Andreas Hindborg <a.hindborg@samsung.com> Link: https://lore.kernel.org/r/20230408122429.1103522-10-y86-dev@protonmail.com Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-04-12rust: init: add initialization macrosBenno Lossin
Add the following initializer macros: - `#[pin_data]` to annotate structurally pinned fields of structs, needed for `pin_init!` and `try_pin_init!` to select the correct initializer of fields. - `pin_init!` create a pin-initializer for a struct with the `Infallible` error type. - `try_pin_init!` create a pin-initializer for a struct with a custom error type (`kernel::error::Error` is the default). - `init!` create an in-place-initializer for a struct with the `Infallible` error type. - `try_init!` create an in-place-initializer for a struct with a custom error type (`kernel::error::Error` is the default). Also add their needed internal helper traits and structs. Co-developed-by: Gary Guo <gary@garyguo.net> Signed-off-by: Gary Guo <gary@garyguo.net> Signed-off-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Reviewed-by: Andreas Hindborg <a.hindborg@samsung.com> Link: https://lore.kernel.org/r/20230408122429.1103522-8-y86-dev@protonmail.com [ Fixed three typos. ] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-04-12rust: macros: add `quote!` macroGary Guo
Add the `quote!` macro for creating `TokenStream`s directly via the given Rust tokens. It also supports repetitions using iterators. It will be used by the pin-init API proc-macros to generate code. Signed-off-by: Gary Guo <gary@garyguo.net> Signed-off-by: Benno Lossin <benno.lossin@proton.me> Reviewed-by: Andreas Hindborg <a.hindborg@samsung.com> Reviewed-by: Alice Ryhl <aliceryhl@google.com> Link: https://lore.kernel.org/r/20230408122429.1103522-3-y86-dev@protonmail.com Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-04-12rust: error: Rename to_kernel_errno() -> to_errno()Asahi Lina
This is kernel code, so specifying "kernel" is redundant. Let's simplify things and just call it to_errno(). Reviewed-by: Gary Guo <gary@garyguo.net> Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com> Signed-off-by: Asahi Lina <lina@asahilina.net> Link: https://lore.kernel.org/r/20230224-rust-error-v3-1-03779bddc02b@asahilina.net Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2023-04-10rust: macros: Allow specifying multiple module aliasesAsahi Lina
Modules can (and usually do) have multiple alias tags, in order to specify multiple possible device matches for autoloading. Allow this by changing the alias ModuleInfo field to an Option<Vec<String>>. Note: For normal device IDs this is autogenerated by modpost (which is not properly integrated with Rust support yet), so it is useful to be able to manually add device match aliases for now, and should still be useful in the future for corner cases that modpost does not handle. This pulls in the expect_group() helper from the rfl/rust branch (with credit to authors). Co-developed-by: Miguel Ojeda <ojeda@kernel.org> Signed-off-by: Miguel Ojeda <ojeda@kernel.org> Co-developed-by: Finn Behrens <me@kloenk.dev> Signed-off-by: Finn Behrens <me@kloenk.dev> Co-developed-by: Sumera Priyadarsini <sylphrenadin@gmail.com> Signed-off-by: Sumera Priyadarsini <sylphrenadin@gmail.com> Reviewed-by: Vincenzo Palazzo <vincenzopalazzodev@gmail.com> Signed-off-by: Asahi Lina <lina@asahilina.net> Link: https://lore.kernel.org/r/20230224-rust-macros-v2-1-7396e8b7018d@asahilina.net Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2022-12-04rust: macros: take string literals in `module!`Gary Guo
Instead of taking binary string literals, take string ones instead, making it easier for users to define a module, i.e. instead of calling `module!` like: module! { ... name: b"rust_minimal", ... } now it is called as: module! { ... name: "rust_minimal", ... } Module names, aliases and license strings are restricted to ASCII only. However, the author and the description allows UTF-8. For simplicity (avoid parsing), escape sequences and raw string literals are not yet handled. Link: https://github.com/Rust-for-Linux/linux/issues/252 Link: https://lore.kernel.org/lkml/YukvvPOOu8uZl7+n@yadro.com/ Signed-off-by: Gary Guo <gary@garyguo.net> [Reworded, adapted for upstream and applied latest changes] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2022-12-04rust: macros: add `#[vtable]` proc macroGary Guo
This procedural macro attribute provides a simple way to declare a trait with a set of operations that later users can partially implement, providing compile-time `HAS_*` boolean associated constants that indicate whether a particular operation was overridden. This is useful as the Rust counterpart to structs like `file_operations` where some pointers may be `NULL`, indicating an operation is not provided. For instance: #[vtable] trait Operations { fn read(...) -> Result<usize> { Err(EINVAL) } fn write(...) -> Result<usize> { Err(EINVAL) } } #[vtable] impl Operations for S { fn read(...) -> Result<usize> { ... } } assert_eq!(<S as Operations>::HAS_READ, true); assert_eq!(<S as Operations>::HAS_WRITE, false); Signed-off-by: Gary Guo <gary@garyguo.net> Reviewed-by: Sergio González Collado <sergio.collado@gmail.com> [Reworded, adapted for upstream and applied latest changes] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2022-12-04rust: macros: add `concat_idents!` proc macroBjörn Roy Baron
This macro provides similar functionality to the unstable feature `concat_idents` without having to rely on it. For instance: let x_1 = 42; let x_2 = concat_idents!(x, _1); assert!(x_1 == x_2); It has different behavior with respect to macro hygiene. Unlike the unstable `concat_idents!` macro, it allows, for example, referring to local variables by taking the span of the second macro as span for the output identifier. Signed-off-by: Björn Roy Baron <bjorn3_gh@protonmail.com> Reviewed-by: Finn Behrens <me@kloenk.dev> Reviewed-by: Gary Guo <gary@garyguo.net> [Reworded, adapted for upstream and applied latest changes] Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
2022-09-28rust: add `macros` crateMiguel Ojeda
This crate contains all the procedural macros ("proc macros") shared by all the kernel. Procedural macros allow to create syntax extensions. They run at compile-time and can consume as well as produce Rust syntax. For instance, the `module!` macro that is used by Rust modules is implemented here. It allows to easily declare the equivalent information to the `MODULE_*` macros in C modules, e.g.: module! { type: RustMinimal, name: b"rust_minimal", author: b"Rust for Linux Contributors", description: b"Rust minimal sample", license: b"GPL", } Co-developed-by: Alex Gaynor <alex.gaynor@gmail.com> Signed-off-by: Alex Gaynor <alex.gaynor@gmail.com> Co-developed-by: Finn Behrens <me@kloenk.de> Signed-off-by: Finn Behrens <me@kloenk.de> Co-developed-by: Adam Bratschi-Kaye <ark.email@gmail.com> Signed-off-by: Adam Bratschi-Kaye <ark.email@gmail.com> Co-developed-by: Wedson Almeida Filho <wedsonaf@google.com> Signed-off-by: Wedson Almeida Filho <wedsonaf@google.com> Co-developed-by: Sumera Priyadarsini <sylphrenadin@gmail.com> Signed-off-by: Sumera Priyadarsini <sylphrenadin@gmail.com> Co-developed-by: Gary Guo <gary@garyguo.net> Signed-off-by: Gary Guo <gary@garyguo.net> Co-developed-by: Matthew Bakhtiari <dev@mtbk.me> Signed-off-by: Matthew Bakhtiari <dev@mtbk.me> Co-developed-by: Björn Roy Baron <bjorn3_gh@protonmail.com> Signed-off-by: Björn Roy Baron <bjorn3_gh@protonmail.com> Signed-off-by: Miguel Ojeda <ojeda@kernel.org>