rust: error: improve unsafe code in example

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 <kernel@valentinobst.de>
Reviewed-by: Martin Rodriguez Reboredo <yakoyoku@gmail.com>
Reviewed-by: Alice Ryhl <aliceryhl@google.com>
Reviewed-by: Trevor Gross <tmgross@umich.edu>
Link: https://lore.kernel.org/r/20240131-doc-fixes-v3-v3-2-0c8af94ed7de@valentinobst.de
Signed-off-by: Miguel Ojeda <ojeda@kernel.org>
This commit is contained in:
Valentin Obst 2024-01-31 21:23:24 +01:00 committed by Miguel Ojeda
parent b6cda913bb
commit 69d5fbb015

View file

@ -264,13 +264,9 @@ pub fn to_result(err: core::ffi::c_int) -> Result {
/// pdev: &mut PlatformDevice,
/// index: u32,
/// ) -> Result<*mut core::ffi::c_void> {
/// // SAFETY: FFI call.
/// unsafe {
/// from_err_ptr(bindings::devm_platform_ioremap_resource(
/// pdev.to_ptr(),
/// index,
/// ))
/// }
/// // SAFETY: `pdev` points to a valid platform device. There are no safety requirements
/// // on `index`.
/// from_err_ptr(unsafe { bindings::devm_platform_ioremap_resource(pdev.to_ptr(), index) })
/// }
/// ```
// TODO: Remove `dead_code` marker once an in-kernel client is available.