[PATCH v2 00/28] Rust core additions

ojeda
2022-12-02T16:15:28Z

From: Miguel Ojeda <ojeda@kernel.org>

This is v2 of the first batch of changes to upstream the rest of
the Rust support. v1 is at:

https://lore.kernel.org/rust-for-linux/20221110164152.26136-1-ojeda@kernel.org/

I collected the tags and applied the agreed changes. The full diff
follows (with respect to v1), since they are minor enough.

I will be applying the patches tomorrow, since v1 has had more than
three weeks of review time.

diff --git a/rust/build_error.rs b/rust/build_error.rs
index 0ff6b33059aa..fa24eeef9929 100644
--- a/rust/build_error.rs
+++ b/rust/build_error.rs
@@ -2,19 +2,26 @@

//! Build-time error.
//!
-//! This crate provides a function `build_error`, which will panic in
-//! compile-time if executed in const context, and will cause a build error
-//! if not executed at compile time and the optimizer does not optimise away the
-//! call.
+//! This crate provides a [const function][const-functions] `build_error`, which will panic in
+//! compile-time if executed in [const context][const-context], and will cause a build error
+//! if not executed at compile time and the optimizer does not optimise away the call.
//!
//! It is used by `build_assert!` in the kernel crate, allowing checking of
//! conditions that could be checked statically, but could not be enforced in
-//! Rust yet (e.g. perform some checks in const functions, but those
+//! Rust yet (e.g. perform some checks in [const functions][const-functions], but those
//! functions could still be called in the runtime).
+//!
+//! For details on constant evaluation in Rust, please see the [Reference][const-eval].
+//!
+//! [const-eval]: https://doc.rust-lang.org/reference/const_eval.html
+//! [const-functions]: https://doc.rust-lang.org/reference/const_eval.html#const-functions
+//! [const-context]: https://doc.rust-lang.org/reference/const_eval.html#const-context

#![no_std]

-/// Panics if executed in const context, or triggers a build error if not.
+/// Panics if executed in [const context][const-context], or triggers a build error if not.
+///
+/// [const-context]: https://doc.rust-lang.org/reference/const_eval.html#const-context
#[inline(never)]
#[cold]
#[export_name = "rust_build_error"]
diff --git a/rust/kernel/std_vendor.rs b/rust/kernel/std_vendor.rs
index da57b4e521f4..b3e68b24a8c6 100644
--- a/rust/kernel/std_vendor.rs
+++ b/rust/kernel/std_vendor.rs
@@ -35,9 +35,12 @@
/// This is useful when debugging issues that only occur in release
/// builds or when debugging in release mode is significantly faster.
///
-/// Note that the macro is intended as a debugging tool and therefore you
-/// should avoid having uses of it in version control for long periods
-/// (other than in tests and similar).
+/// Note that the macro is intended as a temporary debugging tool to be
+/// used during development. Therefore, avoid committing `dbg!` macro
+/// invocations into the kernel tree.
+///
+/// For debug output that is intended to be kept in the kernel tree,
+/// use [`pr_debug`] and similar facilities instead.
///
/// # Stability
///
diff --git a/rust/kernel/str.rs b/rust/kernel/str.rs
index ffac633423db..b771310fa4a4 100644
--- a/rust/kernel/str.rs
+++ b/rust/kernel/str.rs
@@ -129,18 +129,6 @@ impl CStr {
Ok(unsafe { Self::from_bytes_with_nul_unchecked(bytes) })
}

- /// Creates a [`CStr`] from a `[u8]`, panic if input is not valid.
- ///
- /// This function is only meant to be used by `c_str!` macro, so
- /// crates using `c_str!` macro don't have to enable `const_panic` feature.
- #[doc(hidden)]
- pub const fn from_bytes_with_nul_unwrap(bytes: &[u8]) -> &Self {
- match Self::from_bytes_with_nul(bytes) {
- Ok(v) => v,
- Err(_) => panic!("string contains interior NUL"),
- }
- }
-
/// Creates a [`CStr`] from a `[u8]` without performing any additional
/// checks.
///
@@ -349,7 +337,10 @@ where
macro_rules! c_str {
($str:expr) => {{
const S: &str = concat!($str, "\0");
- const C: &$crate::str::CStr = $crate::str::CStr::from_bytes_with_nul_unwrap(S.as_bytes());
+ const C: &$crate::str::CStr = match $crate::str::CStr::from_bytes_with_nul(S.as_bytes()) {
+ Ok(v) => v,
+ Err(_) => panic!("string contains interior NUL"),
+ };
C
}};
}
diff --git a/rust/macros/concat_idents.rs b/rust/macros/concat_idents.rs
index 3b5a9dd70e8a..7e4b450f3a50 100644
--- a/rust/macros/concat_idents.rs
+++ b/rust/macros/concat_idents.rs
@@ -18,6 +18,6 @@ pub(crate) fn concat_idents(ts: TokenStream) -> TokenStream {
assert_eq!(expect_punct(&mut it), ',');
let b = expect_ident(&mut it);
assert!(it.next().is_none(), "only two idents can be concatenated");
- let res = Ident::new(&(a.to_string() + &b.to_string()), b.span());
+ let res = Ident::new(&format!("{a}{b}"), b.span());
TokenStream::from_iter([TokenTree::Ident(res)])
}

Björn Roy Baron (1):
rust: macros: add `concat_idents!` proc macro

Finn Behrens (1):
rust: error: declare errors using macro

Gary Guo (9):
rust: macros: add `#[vtable]` proc macro
rust: macros: take string literals in `module!`
rust: str: add `BStr` type
rust: str: add `b_str!` macro
rust: str: add `CStr` type
rust: str: implement several traits for `CStr`
rust: str: add `c_str!` macro
rust: add `build_error` crate
rust: build_assert: add `build_{error,assert}!` macros

Miguel Ojeda (7):
rust: prelude: split re-exports into groups
rust: print: add more `pr_*!` levels
rust: print: add `pr_cont!` macro
rust: samples: add `rust_print` example
rust: alloc: add `RawVec::try_with_capacity_in()` constructor
rust: alloc: add `Vec::try_with_capacity{,_in}()` constructors
rust: static_assert: add `static_assert!` macro

Milan Landaverde (1):
rust: str: add `CStr` unit tests

Niklas Mohrin (1):
rust: std_vendor: add `dbg!` macro based on `std`'s one

Viktor Garske (1):
rust: error: add codes from `errno-base.h`

Wedson Almeida Filho (7):
rust: error: add `From` implementations for `Error`
rust: prelude: add `error::code::*` constant items
rust: str: add `Formatter` type
rust: str: add `CString` type
rust: str: add `fmt!` macro
rust: types: add `Either` type
rust: types: add `Opaque` type

lib/Kconfig.debug | 16 +
rust/Makefile | 22 +-
rust/alloc/raw_vec.rs | 33 +-
rust/alloc/vec/mod.rs | 89 +++++
rust/build_error.rs | 31 ++
rust/exports.c | 5 +
rust/kernel/build_assert.rs | 82 +++++
rust/kernel/error.rs | 90 ++++-
rust/kernel/lib.rs | 9 +
rust/kernel/prelude.rs | 20 +-
rust/kernel/print.rs | 214 +++++++++++-
rust/kernel/static_assert.rs | 34 ++
rust/kernel/std_vendor.rs | 163 ++++++++++
rust/kernel/str.rs | 523 +++++++++++++++++++++++++++++-
rust/kernel/types.rs | 37 +++
rust/macros/concat_idents.rs | 23 ++
rust/macros/helpers.rs | 24 +-
rust/macros/lib.rs | 108 +++++-
rust/macros/module.rs | 10 +-
rust/macros/vtable.rs | 95 ++++++
samples/rust/Kconfig | 10 +
samples/rust/Makefile | 1 +
samples/rust/rust_minimal.rs | 8 +-
samples/rust/rust_print.rs | 54 +++
scripts/generate_rust_analyzer.py | 8 +-
25 files changed, 1667 insertions(+), 42 deletions(-)
create mode 100644 rust/build_error.rs
create mode 100644 rust/kernel/build_assert.rs
create mode 100644 rust/kernel/static_assert.rs
create mode 100644 rust/kernel/std_vendor.rs
create mode 100644 rust/kernel/types.rs
create mode 100644 rust/macros/concat_idents.rs
create mode 100644 rust/macros/vtable.rs
create mode 100644 samples/rust/rust_print.rs

base-commit: f0c4d9fc9cc9462659728d168387191387e903cc
--
2.38.1