From 086fbfa3b328901fa8b369093ba468864e20544e Mon Sep 17 00:00:00 2001 From: Wedson Almeida Filho Date: Mon, 3 Apr 2023 18:48:13 +0900 Subject: rust: error: Add to_result() helper 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/kernel/error.rs | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) (limited to 'rust/kernel') diff --git a/rust/kernel/error.rs b/rust/kernel/error.rs index 0223d48ab43d..7e25871063df 100644 --- a/rust/kernel/error.rs +++ b/rust/kernel/error.rs @@ -76,7 +76,6 @@ impl Error { /// /// It is a bug to pass an out-of-range `errno`. `EINVAL` would /// be returned in such a case. - #[allow(dead_code)] pub(crate) fn from_errno(errno: core::ffi::c_int) -> Error { if errno < -(bindings::MAX_ERRNO as i32) || errno >= 0 { // TODO: Make it a `WARN_ONCE` once available. @@ -180,3 +179,13 @@ impl From for Error { /// it should still be modeled as returning a `Result` rather than /// just an [`Error`]. pub type Result = core::result::Result; + +/// Converts an integer as returned by a C kernel function to an error if it's negative, and +/// `Ok(())` otherwise. +pub fn to_result(err: core::ffi::c_int) -> Result { + if err < 0 { + Err(Error::from_errno(err)) + } else { + Ok(()) + } +} -- cgit v1.2.3