From patchwork Fri Jan 4 21:16:12 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: 10748847 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 0430591E for ; Fri, 4 Jan 2019 21:37:39 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id DE2D7287C3 for ; Fri, 4 Jan 2019 21:37:38 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id D239A287C9; Fri, 4 Jan 2019 21:37:38 +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 C80FB287C3 for ; Fri, 4 Jan 2019 21:37:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726094AbfADVhh (ORCPT ); Fri, 4 Jan 2019 16:37:37 -0500 Received: from gateway22.websitewelcome.com ([192.185.47.79]:17677 "EHLO gateway22.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726075AbfADVhh (ORCPT ); Fri, 4 Jan 2019 16:37:37 -0500 Received: from cm10.websitewelcome.com (cm10.websitewelcome.com [100.42.49.4]) by gateway22.websitewelcome.com (Postfix) with ESMTP id CF239156BA for ; Fri, 4 Jan 2019 15:16:16 -0600 (CST) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id fWpEgtJ5m2PzOfWpEgZ2o6; Fri, 04 Jan 2019 15:16:16 -0600 X-Authority-Reason: nr=8 Received: from [189.250.130.205] (port=41026 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.91) (envelope-from ) id 1gfWpC-002snh-Q7; Fri, 04 Jan 2019 15:16:16 -0600 Date: Fri, 4 Jan 2019 15:16:12 -0600 From: "Gustavo A. R. Silva" To: Laxman Dewangan , Jon Hunter , Dan Williams , Vinod Koul , Thierry Reding Cc: dmaengine@vger.kernel.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH] dmaengine: tegra-apb: Use struct_size() in devm_kzalloc() Message-ID: <20190104211612.GA14300@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: 189.250.130.205 X-Source-L: No X-Exim-ID: 1gfWpC-002snh-Q7 X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [189.250.130.205]:41026 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 9 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes Sender: dmaengine-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: dmaengine@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; void *entry[]; }; instance = devm_kzalloc(dev, sizeof(struct foo) + sizeof(void *) * count, 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); This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva --- drivers/dma/tegra20-apb-dma.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/dma/tegra20-apb-dma.c b/drivers/dma/tegra20-apb-dma.c index 9a558e30c461..697f316055cf 100644 --- a/drivers/dma/tegra20-apb-dma.c +++ b/drivers/dma/tegra20-apb-dma.c @@ -1319,8 +1319,9 @@ static int tegra_dma_probe(struct platform_device *pdev) return -ENODEV; } - tdma = devm_kzalloc(&pdev->dev, sizeof(*tdma) + cdata->nr_channels * - sizeof(struct tegra_dma_channel), GFP_KERNEL); + tdma = devm_kzalloc(&pdev->dev, + struct_size(tdma, channels, cdata->nr_channels), + GFP_KERNEL); if (!tdma) return -ENOMEM;