linux.git/rust/kernel/error.rs, branch v6.6.132

rust: error: add missing newline to pr_warn! calls

2025-03-22T19:50:48+00:00

[ Upstream commit 6f5c36f56d475732981dcf624e0ac0cc7c8984c8 ]

Added missing newline at the end of pr_warn! usage
so the log is not missed.

Fixes: 6551a7fe0acb ("rust: error: Add Error::from_errno{_unchecked}()")
Reported-by: Miguel Ojeda 
Link: https://github.com/Rust-for-Linux/linux/issues/1139
Signed-off-by: Alban Kurti 
Link: https://lore.kernel.org/r/20250206-printing_fix-v3-2-a85273b501ae@invicto.ai
[ Replaced Closes with Link since it fixes part of the issue. - Miguel ]
Signed-off-by: Miguel Ojeda 
Signed-off-by: Sasha Levin

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

rust: error: `impl Debug` for `Error` with `errname()` integration

2023-06-12T23:24:42+00:00

Integrate the `Error` type with `errname()` by providing a new
`name()` method.

Then, implement `Debug` for the type using the new method.

[ Miguel: under `CONFIG_SYMBOLIC_ERRNAME=n`, `errname()` is a
  `static inline`, so added a helper to support that case,
  like we had in the `rust` branch. Also moved `#include` up
  and reworded commit message for clarity. ]

Co-developed-by: Wedson Almeida Filho 
Signed-off-by: Wedson Almeida Filho 
Co-developed-by: Sven Van Asbroeck 
Signed-off-by: Sven Van Asbroeck 
Signed-off-by: Gary Guo 
Signed-off-by: Alice Ryhl 
Reviewed-by: Martin Rodriguez Reboredo 
Link: https://lore.kernel.org/r/20230531174450.3733220-1-aliceryhl@google.com
Signed-off-by: Miguel Ojeda

rust: error: add missing error codes

2023-05-31T16:53:10+00:00

This adds the error codes from `include/linux/errno.h` to the list of
Rust error constants. These errors were not included originally, because
they are not supposed to be visible from userspace. However, they are
still a perfectly valid error to use when writing a kernel driver. For
example, you might want to return ERESTARTSYS if you receive a signal
during a call to `schedule`.

This patch inserts an annotation to skip rustfmt on the list of error
codes. Without it, three of the error codes are split over several
lines, which looks terribly inconsistent.

Signed-off-by: Alice Ryhl 
Reviewed-by: Martin Rodriguez Reboredo 
Link: https://lore.kernel.org/r/20230504064854.774820-1-aliceryhl@google.com
Signed-off-by: Miguel Ojeda

rust: error: allow specifying error type on `Result`

2023-05-31T16:53:10+00:00

Currently, if the `kernel::error::Result` type is in scope (which is
often is, since it's in the kernel's prelude), you cannot write
`Result` when you want to use a different error
type than `kernel::error::Error`.

To solve this we change the error type from being hard-coded to just
being a default generic parameter. This still lets you write `Result`
when you just want to use the `Error` error type, but also lets you
write `Result` when necessary.

Signed-off-by: Alice Ryhl 
Reviewed-by: Benno Lossin 
Reviewed-by: Asahi Lina 
Reviewed-by: Andreas Hindborg 
Reviewed-by: Gary Guo 
Link: https://lore.kernel.org/r/20230502124015.356001-1-aliceryhl@google.com
Signed-off-by: Miguel Ojeda

rust: error: Add from_result() helper

2023-04-12T16:41:04+00:00

Add a helper function to easily return C result codes from a Rust function
that calls functions which return a Result.

Lina: Imported from rust-for-linux/rust, originally developed by Wedson
as part of file_operations.rs. Added the allow() flags since there is no
user in the kernel crate yet and fixed a typo in a comment. Replaced the
macro with a function taking a closure, per discussion on the ML.

Co-developed-by: Fox Chen 
Signed-off-by: Fox Chen 
Co-developed-by: Miguel Ojeda 
Signed-off-by: Miguel Ojeda 
Signed-off-by: Wedson Almeida Filho 
Reviewed-by: Martin Rodriguez Reboredo 
Signed-off-by: Asahi Lina 
Link: https://lore.kernel.org/r/20230224-rust-error-v3-6-03779bddc02b@asahilina.net
Signed-off-by: Miguel Ojeda

rust: error: Add a helper to convert a C ERR_PTR to a `Result`

2023-04-12T16:41:04+00:00

Some kernel C API functions return a pointer which embeds an optional
`errno`. Callers are supposed to check the returned pointer with
`IS_ERR()` and if this returns `true`, retrieve the `errno` using
`PTR_ERR()`.

Create a Rust helper function to implement the Rust equivalent:
transform a `*mut T` to `Result<*mut T>`.

Lina: Imported from rust-for-linux/linux, with subsequent refactoring
and contributions squashed in and attributed below. Renamed the function
to from_err_ptr().

Co-developed-by: Boqun Feng 
Signed-off-by: Boqun Feng 
Co-developed-by: Miguel Ojeda 
Signed-off-by: Miguel Ojeda 
Co-developed-by: Fox Chen 
Signed-off-by: Fox Chen 
Co-developed-by: Gary Guo 
Signed-off-by: Gary Guo 
Signed-off-by: Sven Van Asbroeck 
Reviewed-by: Martin Rodriguez Reboredo 
Signed-off-by: Asahi Lina 
Link: https://lore.kernel.org/r/20230224-rust-error-v3-5-03779bddc02b@asahilina.net
[ Add a removal of `#[allow(dead_code)]`. ]
Signed-off-by: Miguel Ojeda

rust: error: Add to_result() helper

2023-04-12T16:41:04+00:00

Add a to_result() helper to convert kernel C return values to a Rust
Result, mapping >=0 values to Ok(()) and negative values to Err(...),
with Error::from_errno() ensuring that the errno is within range.

Lina: Imported from rust-for-linux/rust, originally developed by Wedson
as part of the AMBA device driver support.

Signed-off-by: Wedson Almeida Filho 
Reviewed-by: Andreas Hindborg 
Reviewed-by: Gary Guo 
Reviewed-by: Martin Rodriguez Reboredo 
Signed-off-by: Asahi Lina 
Link: https://lore.kernel.org/r/20230224-rust-error-v3-4-03779bddc02b@asahilina.net
[ Add a removal of `#[allow(dead_code)]`. ]
Signed-off-by: Miguel Ojeda

rust: error: Add Error::from_errno{_unchecked}()

2023-04-12T16:41:04+00:00

Add a function to create `Error` values out of a kernel error return,
which safely upholds the invariant that the error code is well-formed
(negative and greater than -MAX_ERRNO). If a malformed code is passed
in, it will be converted to EINVAL.

Lina: Imported from rust-for-linux/rust as authored by Miguel and Fox
with refactoring from Wedson, renamed from_kernel_errno() to
from_errno().

Co-developed-by: Fox Chen 
Signed-off-by: Fox Chen 
Co-developed-by: Wedson Almeida Filho 
Signed-off-by: Wedson Almeida Filho 
Signed-off-by: Miguel Ojeda 
Reviewed-by: Andreas Hindborg 
Reviewed-by: Gary Guo 
Reviewed-by: Martin Rodriguez Reboredo 
Signed-off-by: Asahi Lina 
Link: https://lore.kernel.org/r/20230224-rust-error-v3-3-03779bddc02b@asahilina.net
[ Mark the new associated functions as `#[allow(dead_code)]`. ]
Signed-off-by: Miguel Ojeda