From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5E841C74A5B for ; Wed, 29 Mar 2023 12:05:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229991AbjC2MFF (ORCPT ); Wed, 29 Mar 2023 08:05:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43470 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229477AbjC2MFD (ORCPT ); Wed, 29 Mar 2023 08:05:03 -0400 Received: from mail.marcansoft.com (marcansoft.com [212.63.210.85]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 03166468B; Wed, 29 Mar 2023 05:04:59 -0700 (PDT) Received: from [127.0.0.1] (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: linasend@asahilina.net) by mail.marcansoft.com (Postfix) with ESMTPSA id 1B3A4424A5; Wed, 29 Mar 2023 12:04:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=asahilina.net; s=default; t=1680091498; bh=D4/twBr+bzIjY4ZGn+sbXBAJvi8KroM1AK8OX54iYyI=; h=From:Date:Subject:References:In-Reply-To:To:Cc; b=O9YVbyPosEDBz1Y3e376jGTJdPZ56RObMPGEQKs2kbZDSMJLGz0iqM48RP9Bgg4jP 9j92qyyx8XYyVdP9cHvMvyyaXSRb9OtgPm1wKg/eiWnptEAI6XELAMSSY5aNs1Ar58 X9N0AK2DO4ogwJQwYo2KRRQAeLgzB9Wip9ZJ8n6/0XSPCiOka5Xs06nUzf1sWZ5JgZ LkPFlZMXMaX7E8pZ70aWPsUFsyoarZEJnCR6uF1GjvRmWt+nOWCFN/dmINb2qEsQUW svC9yWrzKhMMRJH07fzM0S9pvF5tlqwpfp2DDeaywrYCtFsFwugn3rLElXy4x5NthK px9nunpoJGpJg== From: Asahi Lina Date: Wed, 29 Mar 2023 21:04:36 +0900 Subject: [PATCH v2 4/6] rust: error: Add to_result() helper MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20230224-rust-error-v2-4-3900319812da@asahilina.net> References: <20230224-rust-error-v2-0-3900319812da@asahilina.net> In-Reply-To: <20230224-rust-error-v2-0-3900319812da@asahilina.net> To: Miguel Ojeda , Alex Gaynor , Wedson Almeida Filho , Boqun Feng , Gary Guo , =?utf-8?q?Bj=C3=B6rn_Roy_Baron?= , Sven Van Asbroeck Cc: Fox Chen , Martin Rodriguez Reboredo , Andreas Hindborg , rust-for-linux@vger.kernel.org, linux-kernel@vger.kernel.org, asahi@lists.linux.dev, Asahi Lina X-Mailer: b4 0.12.0 X-Developer-Signature: v=1; a=ed25519-sha256; t=1680091478; l=1246; i=lina@asahilina.net; s=20230221; h=from:subject:message-id; bh=Pyrepc31fu1j2hIHl+GlAJgfJXkFKrgb4Ue04icQgQk=; b=Qi1Fy6I/4bHQHbB9VuqBIwCJsY+ax2RlS2ro/Kyr4QO8xcgJz+/zdD8IOdnkYaufWCDB//8ot kA5XhtU7hJlADXksO7SehAh9Q98rL6Ptixy/XzzymQEtuAjJBKlp5vR X-Developer-Key: i=lina@asahilina.net; a=ed25519; pk=Qn8jZuOtR1m5GaiDfTrAoQ4NE1XoYVZ/wmt5YtXWFC4= Precedence: bulk List-ID: X-Mailing-List: rust-for-linux@vger.kernel.org From: Wedson Almeida Filho 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 Signed-off-by: Asahi Lina --- rust/kernel/error.rs | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/rust/kernel/error.rs b/rust/kernel/error.rs index 659468bd1735..4f599c4d1752 100644 --- a/rust/kernel/error.rs +++ b/rust/kernel/error.rs @@ -167,3 +167,13 @@ 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(()) + } +} -- 2.40.0