Commit 9a02cbc5 authored Dec 07, 2024 by Daniel Sedlak Committed by Miguel Ojeda Dec 17, 2024

rust: error: modify `from_errno` to use `try_from_errno`

Modify the from_errno function to use try_from_errno to
reduce code duplication while still maintaining all existing
behavior and error handling and also reduces unsafe code.

Link: https://github.com/Rust-for-Linux/linux/issues/1125


Suggested-by: Miguel Ojeda <ojeda@kernel.org>
Co-developed-by: Guilherme Augusto Martins da Silva <guilhermev2huehue@gmail.com>
Signed-off-by: Guilherme Augusto Martins da Silva <guilhermev2huehue@gmail.com>
Signed-off-by: Daniel Sedlak <daniel@sedlak.dev>
Reviewed-by: Fiona Behrens <me@kloenk.dev>
Link: https://lore.kernel.org/r/20241207112445.55502-1-daniel@sedlak.dev


Signed-off-by: Miguel Ojeda <ojeda@kernel.org>

parent 9b98be76

rust/kernel/error.rs

+4 −7

Original line number	Diff line number	Diff line
		@@ -101,19 +101,16 @@ impl Error {
		/// It is a bug to pass an out-of-range `errno`. `EINVAL` would
		/// be returned in such a case.
		pub fn from_errno(errno: crate::ffi::c_int) -> Error {
		if errno < -(bindings::MAX_ERRNO as i32) \|\| errno >= 0 {
		if let Some(error) = Self::try_from_errno(errno) {
		error
		} else {
		// TODO: Make it a `WARN_ONCE` once available.
		crate::pr_warn!(
		"attempted to create `Error` with out of range `errno`: {}",
		errno
		);
		return code::EINVAL;
		code::EINVAL
		}

		// INVARIANT: The check above ensures the type invariant
		// will hold.
		// SAFETY: `errno` is checked above to be in a valid range.
		unsafe { Error::from_errno_unchecked(errno) }
		}

		/// Creates an [`Error`] from a kernel error code.