From patchwork Tue Jun 4 23:16:16 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Gustavo A. R. Silva" X-Patchwork-Id: 10976223 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id F0AB82D49 for ; Tue, 4 Jun 2019 23:43:23 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D9B02287FB for ; Tue, 4 Jun 2019 23:43:23 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id CB08428898; Tue, 4 Jun 2019 23:43:23 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 5452F287FB for ; Tue, 4 Jun 2019 23:43:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726399AbfFDXnX (ORCPT ); Tue, 4 Jun 2019 19:43:23 -0400 Received: from gateway23.websitewelcome.com ([192.185.50.129]:29007 "EHLO gateway23.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726269AbfFDXnW (ORCPT ); Tue, 4 Jun 2019 19:43:22 -0400 X-Greylist: delayed 1452 seconds by postgrey-1.27 at vger.kernel.org; Tue, 04 Jun 2019 19:43:22 EDT Received: from cm10.websitewelcome.com (cm10.websitewelcome.com [100.42.49.4]) by gateway23.websitewelcome.com (Postfix) with ESMTP id 62BAB5A245 for ; Tue, 4 Jun 2019 18:16:18 -0500 (CDT) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id YIfChQkE72PzOYIfChlJVJ; Tue, 04 Jun 2019 18:16:18 -0500 X-Authority-Reason: nr=8 Received: from [189.250.127.120] (port=45750 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.91) (envelope-from ) id 1hYIfB-000fBA-4A; Tue, 04 Jun 2019 18:16:17 -0500 Date: Tue, 4 Jun 2019 18:16:16 -0500 From: "Gustavo A. R. Silva" To: Andy Gross , David Brown , Thomas Gleixner , Jason Cooper , Marc Zyngier Cc: linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH] irqchip/qcom: Use struct_size() in devm_kzalloc() Message-ID: <20190604231616.GA31969@embeddedor> MIME-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.9.4 (2018-02-28) X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - gator4166.hostgator.com X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - embeddedor.com X-BWhitelist: no X-Source-IP: 189.250.127.120 X-Source-L: No X-Exim-ID: 1hYIfB-000fBA-4A X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [189.250.127.120]:45750 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 7 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP One of the more common cases of allocation size calculations is finding the size of a structure that has a zero-sized array at the end, along with memory for some number of elements for that array. For example: struct foo { int stuff; struct boo entry[]; }; size = sizeof(struct foo) + count * sizeof(struct boo); instance = devm_kzalloc(dev, size, GFP_KERNEL); Instead of leaving these open-coded and prone to type mistakes, we can now use the new struct_size() helper: instance = devm_kzalloc(dev, struct_size(instance, entry, count), GFP_KERNEL); Notice that, in this case, variable alloc_sz is not necessary, hence it is removed. This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva --- drivers/irqchip/qcom-irq-combiner.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/irqchip/qcom-irq-combiner.c b/drivers/irqchip/qcom-irq-combiner.c index 7f0c0be322e0..d269a7722032 100644 --- a/drivers/irqchip/qcom-irq-combiner.c +++ b/drivers/irqchip/qcom-irq-combiner.c @@ -237,7 +237,6 @@ static int get_registers(struct platform_device *pdev, struct combiner *comb) static int __init combiner_probe(struct platform_device *pdev) { struct combiner *combiner; - size_t alloc_sz; int nregs; int err; @@ -247,8 +246,8 @@ static int __init combiner_probe(struct platform_device *pdev) return -EINVAL; } - alloc_sz = sizeof(*combiner) + sizeof(struct combiner_reg) * nregs; - combiner = devm_kzalloc(&pdev->dev, alloc_sz, GFP_KERNEL); + combiner = devm_kzalloc(&pdev->dev, struct_size(combiner, regs, nregs), + GFP_KERNEL); if (!combiner) return -ENOMEM;