| 798bb342 | 26-Nov-2024 |
Linus Torvalds <torvalds@linux-foundation.org> |
Merge tag 'rust-6.13' of https://github.com/Rust-for-Linux/linux
Pull rust updates from Miguel Ojeda:
"Toolchain and infrastructure:
- Enable a series of lints, including safety-related ones, e
Merge tag 'rust-6.13' of https://github.com/Rust-for-Linux/linux
Pull rust updates from Miguel Ojeda:
"Toolchain and infrastructure:
- Enable a series of lints, including safety-related ones, e.g. the
compiler will now warn about missing safety comments, as well as
unnecessary ones. How safety documentation is organized is a
frequent source of review comments, thus having the compiler guide
new developers on where they are expected (and where not) is very
nice.
- Start using '#[expect]': an interesting feature in Rust (stabilized
in 1.81.0) that makes the compiler warn if an expected warning was
_not_ emitted. This is useful to avoid forgetting cleaning up
locally ignored diagnostics ('#[allow]'s).
- Introduce '.clippy.toml' configuration file for Clippy, the Rust
linter, which will allow us to tweak its behaviour. For instance,
our first use cases are declaring a disallowed macro and, more
importantly, enabling the checking of private items.
- Lints-related fixes and cleanups related to the items above.
- Migrate from 'receiver_trait' to 'arbitrary_self_types': to get the
kernel into stable Rust, one of the major pieces of the puzzle is
the support to write custom types that can be used as 'self', i.e.
as receivers, since the kernel needs to write types such as 'Arc'
that common userspace Rust would not. 'arbitrary_self_types' has
been accepted to become stable, and this is one of the steps
required to get there.
- Remove usage of the 'new_uninit' unstable feature.
- Use custom C FFI types. Includes a new 'ffi' crate to contain our
custom mapping, instead of using the standard library 'core::ffi'
one. The actual remapping will be introduced in a later cycle.
- Map '__kernel_{size_t,ssize_t,ptrdiff_t}' to 'usize'/'isize'
instead of 32/64-bit integers.
- Fix 'size_t' in bindgen generated prototypes of C builtins.
- Warn on bindgen < 0.69.5 and libclang >= 19.1 due to a double issue
in the projects, which we managed to trigger with the upcoming
tracepoint support. It includes a build test since some
distributions backported the fix (e.g. Debian -- thanks!). All
major distributions we list should be now OK except Ubuntu non-LTS.
'macros' crate:
- Adapt the build system to be able run the doctests there too; and
clean up and enable the corresponding doctests.
'kernel' crate:
- Add 'alloc' module with generic kernel allocator support and remove
the dependency on the Rust standard library 'alloc' and the
extension traits we used to provide fallible methods with flags.
Add the 'Allocator' trait and its implementations '{K,V,KV}malloc'.
Add the 'Box' type (a heap allocation for a single value of type
'T' that is also generic over an allocator and considers the
kernel's GFP flags) and its shorthand aliases '{K,V,KV}Box'. Add
'ArrayLayout' type. Add 'Vec' (a contiguous growable array type)
and its shorthand aliases '{K,V,KV}Vec', including iterator
support.
For instance, now we may write code such as:
let mut v = KVec::new();
v.push(1, GFP_KERNEL)?;
assert_eq!(&v, &[1]);
Treewide, move as well old users to these new types.
- 'sync' module: add global lock support, including the
'GlobalLockBackend' trait; the 'Global{Lock,Guard,LockedBy}' types
and the 'global_lock!' macro. Add the 'Lock::try_lock' method.
- 'error' module: optimize 'Error' type to use 'NonZeroI32' and make
conversion functions public.
- 'page' module: add 'page_align' function.
- Add 'transmute' module with the existing 'FromBytes' and 'AsBytes'
traits.
- 'block::mq::request' module: improve rendered documentation.
- 'types' module: extend 'Opaque' type documentation and add simple
examples for the 'Either' types.
drm/panic:
- Clean up a series of Clippy warnings.
Documentation:
- Add coding guidelines for lints and the '#[expect]' feature.
- Add Ubuntu to the list of distributions in the Quick Start guide.
MAINTAINERS:
- Add Danilo Krummrich as maintainer of the new 'alloc' module.
And a few other small cleanups and fixes"
* tag 'rust-6.13' of https://github.com/Rust-for-Linux/linux: (82 commits)
rust: alloc: Fix `ArrayLayout` allocations
docs: rust: remove spurious item in `expect` list
rust: allow `clippy::needless_lifetimes`
rust: warn on bindgen < 0.69.5 and libclang >= 19.1
rust: use custom FFI integer types
rust: map `__kernel_size_t` and friends also to usize/isize
rust: fix size_t in bindgen prototypes of C builtins
rust: sync: add global lock support
rust: macros: enable the rest of the tests
rust: macros: enable paste! use from macro_rules!
rust: enable macros::module! tests
rust: kbuild: expand rusttest target for macros
rust: types: extend `Opaque` documentation
rust: block: fix formatting of `kernel::block::mq::request` module
rust: macros: fix documentation of the paste! macro
rust: kernel: fix THIS_MODULE header path in ThisModule doc comment
rust: page: add Rust version of PAGE_ALIGN
rust: helpers: remove unnecessary header includes
rust: exports: improve grammar in commentary
drm/panic: allow verbose version check
...
show more ...
|
| 8af7a501 | 20-Nov-2024 |
Miguel Ojeda <ojeda@kernel.org> |
rust: jump_label: skip formatting generated file
After a source tree build of the kernel, and having used the `RSCPP`
rule, running `rustfmt` fails with:
error: macros that expand to items must
rust: jump_label: skip formatting generated file
After a source tree build of the kernel, and having used the `RSCPP`
rule, running `rustfmt` fails with:
error: macros that expand to items must be delimited with braces or followed by a semicolon
--> rust/kernel/arch_static_branch_asm.rs:1:27
|
1 | ...ls!("1: jmp " ... ".popsection \n\t")
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
help: change the delimiters to curly braces
|
1 | ::kernel::concat_literals!{"1: jmp " ... ".popsection \n\t"}
| ~ ~
help: add a semicolon
|
1 | ::kernel::concat_literals!("1: jmp " ... ".popsection \n\t");
| +
This file is not meant to be formatted nor works on its own since it is
meant to be textually included.
Thus skip formatting it by prefixing its name with `generated_`.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alex Gaynor <alex.gaynor@gmail.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Gary Guo <gary@garyguo.net>
Cc: Björn Roy Baron <bjorn3_gh@protonmail.com>
Cc: Benno Lossin <benno.lossin@proton.me>
Cc: Andreas Hindborg <a.hindborg@kernel.org>
Cc: Alice Ryhl <aliceryhl@google.com>
Cc: Trevor Gross <tmgross@umich.edu>
Link: https://lore.kernel.org/20241120175916.58860-1-ojeda@kernel.org
Fixes: 169484ab6677 ("rust: add arch_static_branch")
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
show more ...
|
| 7643155d | 18-Nov-2024 |
Alice Ryhl <aliceryhl@google.com> |
jump_label: rust: pass a mut ptr to `static_key_count`
When building the rust_print sample with CONFIG_JUMP_LABEL=n, the Rust
static key support falls back to using static_key_count. This function
a
jump_label: rust: pass a mut ptr to `static_key_count`
When building the rust_print sample with CONFIG_JUMP_LABEL=n, the Rust
static key support falls back to using static_key_count. This function
accepts a mutable pointer to the `struct static_key`, but the Rust
abstractions are incorrectly passing a const pointer.
This means that builds using CONFIG_JUMP_LABEL=n and SAMPLE_RUST_PRINT=y
fail with the following error message:
error[E0308]: mismatched types
--> <root>/samples/rust/rust_print_main.rs:87:5
|
87 | / kernel::declare_trace! {
88 | | /// # Safety
89 | | ///
90 | | /// Always safe to call.
91 | | unsafe fn rust_sample_loaded(magic: c_int);
92 | | }
| | ^
| | |
| |_____types differ in mutability
| arguments to this function are incorrect
|
= note: expected raw pointer `*mut kernel::bindings::static_key`
found raw pointer `*const kernel::bindings::static_key`
note: function defined here
--> <root>/rust/bindings/bindings_helpers_generated.rs:33:12
|
33 | pub fn static_key_count(key: *mut static_key) -> c_int;
| ^^^^^^^^^^^^^^^^
To fix this, insert a pointer cast so that the pointer is mutable.
Link: https://lore.kernel.org/20241118202727.73646-1-aliceryhl@google.com
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202411181440.qEdcuyh6-lkp@intel.com/
Fixes: 169484ab6677 ("rust: add arch_static_branch")
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
show more ...
|
| 2fd6f55c | 13-Sep-2024 |
Gary Guo <gary@garyguo.net> |
rust: map `__kernel_size_t` and friends also to usize/isize
Currently bindgen has special logic to recognise `size_t` and `ssize_t`
and map them to Rust `usize` and `isize`. Similarly, `ptrdiff_t` i
rust: map `__kernel_size_t` and friends also to usize/isize
Currently bindgen has special logic to recognise `size_t` and `ssize_t`
and map them to Rust `usize` and `isize`. Similarly, `ptrdiff_t` is
mapped to `isize`.
However this falls short for `__kernel_size_t`, `__kernel_ssize_t` and
`__kernel_ptrdiff_t`. To ensure that they are mapped to usize/isize
rather than 32/64 integers depending on platform, blocklist them in
bindgen parameters and manually provide their definition.
Signed-off-by: Gary Guo <gary@garyguo.net>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Trevor Gross <tmgross@umich.edu>
Link: https://lore.kernel.org/r/20240913213041.395655-3-gary@garyguo.net
[ Formatted comment. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
show more ...
|
| 75c1fd41 | 13-Sep-2024 |
Gary Guo <gary@garyguo.net> |
rust: fix size_t in bindgen prototypes of C builtins
Without `-fno-builtin`, for functions like memcpy/memmove (and many
others), bindgen seems to be using the clang-provided prototype. This
prototy
rust: fix size_t in bindgen prototypes of C builtins
Without `-fno-builtin`, for functions like memcpy/memmove (and many
others), bindgen seems to be using the clang-provided prototype. This
prototype is ABI-wise compatible, but the issue is that it does not have
the same information as the source code w.r.t. typedefs.
For example, bindgen generates the following:
extern "C" {
pub fn strlen(s: *const core::ffi::c_char) -> core::ffi::c_ulong;
}
note that the return type is `c_ulong` (i.e. unsigned long), despite the
size_t-is-usize behavior (this is default, and we have not opted out
from it using --no-size_t-is-usize).
Similarly, memchr's size argument should be of type `__kernel_size_t`,
but bindgen generates `c_ulong` directly.
We want to ensure any `size_t` is translated to Rust `usize` so that we
can avoid having them be different type on 32-bit and 64-bit
architectures, and hence would require a lot of excessive type casts
when calling FFI functions.
I found that this bindgen behavior (which probably is caused by
libclang) can be disabled by `-fno-builtin`. Using the flag for compiled
code can result in less optimisation because compiler cannot assume
about their properties anymore, but this should not affect bindgen.
[ Trevor asked: "I wonder how reliable this behavior is. Maybe bindgen
could do a better job controlling this, is there an open issue?".
Gary replied: ..."apparently this is indeed the suggested approach in
https://github.com/rust-lang/rust-bindgen/issues/1770". - Miguel ]
Signed-off-by: Gary Guo <gary@garyguo.net>
Link: https://lore.kernel.org/r/20240913213041.395655-2-gary@garyguo.net
[ Formatted comment. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
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|
| 8eea62ff | 23-Oct-2024 |
Alice Ryhl <aliceryhl@google.com> |
rust: sync: add global lock support
Add support for creating global variables that are wrapped in a mutex or
spinlock.
The implementation here is intended to replace the global mutex
workaround fou
rust: sync: add global lock support
Add support for creating global variables that are wrapped in a mutex or
spinlock.
The implementation here is intended to replace the global mutex
workaround found in the Rust Binder RFC [1]. In both cases, the global
lock must be initialized before first use. The macro is unsafe to use
for the same reason.
The separate initialization step is required because it is tricky to
access the value of __ARCH_SPIN_LOCK_UNLOCKED from Rust. Doing so will
require changes to the C side. That change will happen as a follow-up to
this patch.
Link: https://lore.kernel.org/rust-for-linux/20231101-rust-binder-v1-2-08ba9197f637@google.com/#Z31drivers:android:context.rs [1]
Signed-off-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Link: https://lore.kernel.org/r/20241023-static-mutex-v6-1-d7efdadcc84f@google.com
[ Simplified a few intra-doc links. Formatted a few comments. Reworded
title. - Miguel ]
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
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|