linux-toradex.git/rust/kernel/error.rs, branch v6.12-rc4

rust: error: allow `useless_conversion` for 32-bit builds

2024-08-18T21:10:53+00:00

For the new Rust support for 32-bit arm [1], Clippy warns:

    error: useless conversion to the same type: `i32`
       --> rust/kernel/error.rs:139:36
        |
    139 |         unsafe { bindings::ERR_PTR(self.0.into()) as *mut _ }
        |                                    ^^^^^^^^^^^^^ help: consider removing `.into()`: `self.0`
        |
        = help: for further information visit https://rust-lang.github.io/rust-clippy/master/index.html#useless_conversion
        = note: `-D clippy::useless-conversion` implied by `-D warnings`
        = help: to override `-D warnings` add `#[allow(clippy::useless_conversion)]`

The `self.0.into()` converts an `c_int` into `ERR_PTR`'s parameter
which is a `c_long`. Thus, both types are `i32` in 32-bit. Therefore,
allow it for those architectures.

Link: https://lore.kernel.org/rust-for-linux/2dbd1491-149d-443c-9802-75786a6a3b73@gmail.com/ [1]
Reviewed-by: Alice Ryhl 
Reviewed-by: Christian Schrefl 
Link: https://lore.kernel.org/r/20240730155702.1110144-1-ojeda@kernel.org
[ Fixed typo in tag. - Miguel ]
Signed-off-by: Miguel Ojeda

rust: block: introduce `kernel::block::mq` module

2024-06-14T13:45:04+00:00

Add initial abstractions for working with blk-mq.

This patch is a maintained, refactored subset of code originally published
by Wedson Almeida Filho  [1].

[1] https://github.com/wedsonaf/linux/tree/f2cfd2fe0e2ca4e90994f96afe268bbd4382a891/rust/kernel/blk/mq.rs

Cc: Wedson Almeida Filho 
Signed-off-by: Andreas Hindborg 
Reviewed-by: Benno Lossin 
Link: https://lore.kernel.org/r/20240611114551.228679-2-nmi@metaspace.dk
Signed-off-by: Jens Axboe

rust: kernel: remove redundant imports

2024-05-05T17:22:25+00:00

Rust's `unused_imports` lint covers both unused and redundant imports.
In the upcoming 1.78.0, the lint detects more cases of redundant imports
[1], e.g.:

    error: the item `bindings` is imported redundantly
      --> rust/kernel/print.rs:38:9
       |
    38 |     use crate::bindings;
       |         ^^^^^^^^^^^^^^^ the item `bindings` is already defined by prelude

Most cases are `use crate::bindings`, plus a few other items like `Box`.
Thus clean them up.

Note that, in the `bindings` case, the message "defined by prelude"
above means the extern prelude, i.e. the `--extern` flags we pass.

Link: https://github.com/rust-lang/rust/pull/117772 [1]
Reviewed-by: Alice Ryhl 
Link: https://lore.kernel.org/r/20240401212303.537355-3-ojeda@kernel.org
Signed-off-by: Miguel Ojeda

rust: kernel: remove usage of `allocator_api` unstable feature

2024-04-16T20:50:04+00:00

With the adoption of `BoxExt` and `VecExt`, we don't need the functions
provided by this feature (namely the methods prefixed with `try_` and
different allocator per collection instance).

We do need `AllocError`, but we define our own as it is a trivial empty
struct.

Reviewed-by: Benno Lossin 
Signed-off-by: Wedson Almeida Filho 
Link: https://lore.kernel.org/r/20240328013603.206764-11-wedsonaf@gmail.com
Signed-off-by: Miguel Ojeda

rust: alloc: update `VecExt` to take allocation flags

2024-04-16T20:50:04+00:00

We also rename the methods by removing the `try_` prefix since the names
are available due to our usage of the `no_global_oom_handling` config
when building the `alloc` crate.

Reviewed-by: Boqun Feng 
Signed-off-by: Wedson Almeida Filho 
Reviewed-by: Benno Lossin 
Link: https://lore.kernel.org/r/20240328013603.206764-8-wedsonaf@gmail.com
Signed-off-by: Miguel Ojeda

rust: error: improve unsafe code in example

2024-02-18T20:22:27+00:00

The `from_err_ptr` function is safe. There is no need for the call to it
to be inside the unsafe block.

Reword the SAFETY comment to provide a better justification of why the
FFI call is safe.

Signed-off-by: Valentin Obst 
Reviewed-by: Martin Rodriguez Reboredo 
Reviewed-by: Alice Ryhl 
Reviewed-by: Trevor Gross 
Link: https://lore.kernel.org/r/20240131-doc-fixes-v3-v3-2-0c8af94ed7de@valentinobst.de
Signed-off-by: Miguel Ojeda

rust: support `srctree`-relative links

2023-12-21T19:54:17+00:00

Some of our links use relative paths in order to point to files in the
source tree, e.g.:

    //! C header: [`include/linux/printk.h`](../../../../include/linux/printk.h)
    /// [`struct mutex`]: ../../../../include/linux/mutex.h

These are problematic because they are hard to maintain and do not support
`O=` builds.

Instead, provide support for `srctree`-relative links, e.g.:

    //! C header: [`include/linux/printk.h`](srctree/include/linux/printk.h)
    /// [`struct mutex`]: srctree/include/linux/mutex.h

The links are fixed after `rustdoc` generation to be based on the absolute
path to the source tree.

Essentially, this is the automatic version of Tomonori's fix [1],
suggested by Gary [2].

Suggested-by: Gary Guo 
Reported-by: FUJITA Tomonori 
Closes: https://lore.kernel.org/r/20231026.204058.2167744626131849993.fujita.tomonori@gmail.com [1]
Fixes: 48fadf440075 ("docs: Move rustdoc output, cross-reference it")
Link: https://lore.kernel.org/rust-for-linux/20231026154525.6d14b495@eugeo/ [2]
Reviewed-by: Martin Rodriguez Reboredo 
Reviewed-by: Benno Lossin 
Link: https://lore.kernel.org/r/20231215235428.243211-1-ojeda@kernel.org
Signed-off-by: Miguel Ojeda

rust: macros: improve `#[vtable]` documentation

2023-12-14T19:14:01+00:00

Traits marked with `#[vtable]` need to provide default implementations
for optional functions. The C side represents these with `NULL` in the
vtable, so the default functions are never actually called. We do not
want to replicate the default behavior from C in Rust, because that is
not maintainable. Therefore we should use `build_error` in those default
implementations. The error message for that is provided at
`kernel::error::VTABLE_DEFAULT_ERROR`.

Signed-off-by: Benno Lossin 
Reviewed-by: Martin Rodriguez Reboredo 
Reviewed-by: Andreas Hindborg 
Reviewed-by: Alice Ryhl 
Reviewed-by: Finn Behrens 
Link: https://lore.kernel.org/r/20231026201855.1497680-1-benno.lossin@proton.me
[ Wrapped paragraph to 80 as requested and capitalized sentence. ]
Signed-off-by: Miguel Ojeda

rust: error: Markdown style nit

2023-10-12T20:58:52+00:00

This patch fixes a trivial markdown style nit in the `SAFETY` comment.

Signed-off-by: Manmohan Shukla 
Reviewed-by: Alice Ryhl 
Reviewed-by: Jianguo Bao 
Reviewed-by: Vincenzo Palazzo 
Reviewed-by: Finn Behrens 
Reviewed-by: Benno Lossin 
Reviewed-by: Andreas Hindborg 
Fixes: c7e20faa5fca ("rust: error: Add Error::to_ptr()")
Link: https://lore.kernel.org/r/20230906204857.85619-1-manmshuk@gmail.com
Signed-off-by: Miguel Ojeda

rust: error: fix the description for `ECHILD`

2023-10-12T20:58:28+00:00

A mistake was made and the description of `ECHILD` is wrong (it reuses
the description of `ENOEXEC`). This fixes it to reflect what's in
`errno-base.h`.

Signed-off-by: Wedson Almeida Filho 
Reviewed-by: Martin Rodriguez Reboredo 
Reviewed-by: Trevor Gross 
Reviewed-by: Finn Behrens 
Reviewed-by: Alice Ryhl 
Fixes: 266def2a0f5b ("rust: error: add codes from `errno-base.h`")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20230930144958.46051-1-wedsonaf@gmail.com
[ Use the plural, as noticed by Benno. ]
Signed-off-by: Miguel Ojeda