user/sven/linux.git/rust, branch v6.2.4

rust: print: avoid evaluating arguments in `pr_*` macros in `unsafe` blocks

2023-01-15T23:54:35Z

At the moment it is possible to perform unsafe operations in the arguments of `pr_*` macros since they are evaluated inside an `unsafe` block: let x = &10u32 as *const u32; pr_info!("{}", *x); In other words, this is a soundness issue. Fix it so that it requires an explicit `unsafe` block. Reported-by: Wedson Almeida Filho Reported-by: Domen Puncer Kugler Link: https://github.com/Rust-for-Linux/linux/issues/479 Signed-off-by: Miguel Ojeda Reviewed-by: Boqun Feng Reviewed-by: Gary Guo Reviewed-by: Björn Roy Baron Reviewed-by: Vincenzo Palazzo

rust: types: add `Opaque` type

2022-12-04T00:59:16Z

Add the `Opaque` type, which is meant to be used with FFI objects that are never interpreted by Rust code, e.g.: struct Waiter { completion: Opaque, next: *mut Waiter, } It has the advantage that the objects don't have to be zero-initialised before calling their init functions, making the code performance closer to C. Signed-off-by: Wedson Almeida Filho [Reworded, adapted for upstream and applied latest changes] Signed-off-by: Miguel Ojeda

rust: types: add `Either` type

2022-12-04T00:59:16Z

Introduce the new `types` module of the `kernel` crate with `Either` as its first type. `Either` is a sum type that always holds either a value of type `L` (`Left` variant) or `R` (`Right` variant). For instance: struct Executor { queue: Either, } Signed-off-by: Wedson Almeida Filho Reviewed-by: Wei Liu [Reworded, adapted for upstream and applied latest changes] Signed-off-by: Miguel Ojeda

rust: build_assert: add `build_{error,assert}!` macros

2022-12-04T00:59:16Z

Add the `build_error!` and `build_assert!` macros which leverage the previously introduced `build_error` crate. Do so in a new module, called `build_assert`. The former fails the build if the code path calling it can possibly be executed. The latter asserts that a boolean expression is `true` at compile time. In particular, `build_assert!` can be used in some contexts where `static_assert!` cannot: fn f1() { static_assert!(N > 1);` // Error. build_assert!(N > 1); // Build-time check. assert!(N > 1); // Run-time check. } #[inline] fn f2(n: usize) { static_assert!(n > 1); // Error. build_assert!(n > 1); // Build-time check. assert!(n > 1); // Run-time check. } Signed-off-by: Gary Guo Reviewed-by: Wei Liu [Reworded, adapted for upstream and applied latest changes] Signed-off-by: Miguel Ojeda

rust: add `build_error` crate

2022-12-04T00:59:16Z

The `build_error` crate provides a function `build_error` which will panic at compile-time if executed in const context and, by default, will cause a build error if not executed at compile time and the optimizer does not optimise away the call. The `CONFIG_RUST_BUILD_ASSERT_ALLOW` kernel option allows to relax the default build failure and convert it to a runtime check. If the runtime check fails, `panic!` will be called. Its functionality will be exposed to users as a couple macros in the `kernel` crate in the following patch, thus some documentation here refers to them for simplicity. Signed-off-by: Gary Guo Reviewed-by: Wei Liu [Reworded, adapted for upstream and applied latest changes] Signed-off-by: Miguel Ojeda

rust: static_assert: add `static_assert!` macro

2022-12-04T00:59:16Z

Add the `static_assert!` macro, which is a compile-time assert, similar to the C11 `_Static_assert` and C++11 `static_assert` declarations [1,2]. Do so in a new module, called `static_assert`. For instance: static_assert!(42 > 24); static_assert!(core::mem::size_of::() == 1); const X: &[u8] = b"bar"; static_assert!(X[1] == b'a'); const fn f(x: i32) -> i32 { x + 2 } static_assert!(f(40) == 42); Link: https://en.cppreference.com/w/c/language/_Static_assert [1] Link: https://en.cppreference.com/w/cpp/language/static_assert [2] Co-developed-by: Alex Gaynor Signed-off-by: Alex Gaynor Signed-off-by: Miguel Ojeda

rust: std_vendor: add `dbg!` macro based on `std`'s one

2022-12-04T00:59:16Z

The Rust standard library has a really handy macro, `dbg!` [1,2]. It prints the source location (filename and line) along with the raw source code that is invoked with and the `Debug` representation of the given expression, e.g.: let a = 2; let b = dbg!(a * 2) + 1; // ^-- prints: [src/main.rs:2] a * 2 = 4 assert_eq!(b, 5); Port the macro over to the `kernel` crate inside a new module called `std_vendor`, using `pr_info!` instead of `eprintln!` and make the rules about committing uses of `dbg!` into version control more concrete (i.e. tailored for the kernel). Since the source code for the macro is taken from the standard library source (with only minor adjustments), the new file is licensed under `Apache 2.0 OR MIT`, just like the original [3,4]. Link: https://doc.rust-lang.org/std/macro.dbg.html [1] Link: https://github.com/rust-lang/rust/blob/master/library/std/src/macros.rs#L212 [2] Link: https://github.com/rust-lang/rust/blob/master/library/std/Cargo.toml [3] Link: https://github.com/rust-lang/rust/blob/master/COPYRIGHT [4] Signed-off-by: Niklas Mohrin [Reworded, adapted for upstream and applied latest changes] Signed-off-by: Miguel Ojeda

rust: str: add `fmt!` macro

2022-12-04T00:59:16Z

Add the `fmt!` macro, which is a convenience alias for the Rust `core::format_args!` macro. For instance, it may be used to create a `CString`: CString::try_from_fmt(fmt!("{}{}", "abc", 42))? Signed-off-by: Wedson Almeida Filho Reviewed-by: Gary Guo [Reworded, adapted for upstream and applied latest changes] Signed-off-by: Miguel Ojeda

rust: str: add `CString` type

2022-12-04T00:59:15Z

Add the `CString` type, which is an owned string that is guaranteed to have exactly one `NUL` byte at the end, i.e. the owned equivalent to `CStr` introduced earlier. It is used for interoperability with kernel APIs that take C strings. In order to do so, implement the `RawFormatter::new()` constructor and the `RawFormatter::bytes_written()` method as well. Signed-off-by: Wedson Almeida Filho [Reworded, adapted for upstream and applied latest changes] Signed-off-by: Miguel Ojeda

rust: str: add `Formatter` type

2022-12-04T00:59:15Z

Add the `Formatter` type, which leverages `RawFormatter`, but fails if callers attempt to write more than will fit in the buffer. In order to so, implement the `RawFormatter::from_buffer()` constructor as well. Co-developed-by: Adam Bratschi-Kaye Signed-off-by: Adam Bratschi-Kaye Signed-off-by: Wedson Almeida Filho Reviewed-by: Gary Guo [Reworded, adapted for upstream and applied latest changes] Signed-off-by: Miguel Ojeda