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 X-Spam-Level: X-Spam-Status: No, score=-8.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4B297C282CE for ; Tue, 4 Jun 2019 23:32:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2E033206B8 for ; Tue, 4 Jun 2019 23:32:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727872AbfFDXcJ (ORCPT ); Tue, 4 Jun 2019 19:32:09 -0400 Received: from gateway34.websitewelcome.com ([192.185.148.164]:23764 "EHLO gateway34.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727372AbfFDXcI (ORCPT ); Tue, 4 Jun 2019 19:32:08 -0400 Received: from cm11.websitewelcome.com (cm11.websitewelcome.com [100.42.49.5]) by gateway34.websitewelcome.com (Postfix) with ESMTP id B28F5615C8 for ; Tue, 4 Jun 2019 18:32:07 -0500 (CDT) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id YIuVh73g2dnCeYIuVhkf6E; Tue, 04 Jun 2019 18:32:07 -0500 X-Authority-Reason: nr=8 Received: from [189.250.127.120] (port=46282 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.91) (envelope-from ) id 1hYIuU-000mO4-N5; Tue, 04 Jun 2019 18:32:06 -0500 Date: Tue, 4 Jun 2019 18:32:05 -0500 From: "Gustavo A. R. Silva" To: Bartlomiej Zolnierkiewicz Cc: dri-devel@lists.freedesktop.org, linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH] video: fbdev-MMP: Use struct_size() in devm_kzalloc() Message-ID: <20190604233205.GA5377@embeddedor> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii 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: 1hYIuU-000mO4-N5 X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [189.250.127.120]:46282 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 14 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 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 size is not necessary, hence it is removed. This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva --- drivers/video/fbdev/mmp/hw/mmp_ctrl.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/video/fbdev/mmp/hw/mmp_ctrl.c b/drivers/video/fbdev/mmp/hw/mmp_ctrl.c index 87d943f15a12..17174cd7a5bb 100644 --- a/drivers/video/fbdev/mmp/hw/mmp_ctrl.c +++ b/drivers/video/fbdev/mmp/hw/mmp_ctrl.c @@ -433,7 +433,7 @@ static int mmphw_probe(struct platform_device *pdev) { struct mmp_mach_plat_info *mi; struct resource *res; - int ret, i, size, irq; + int ret, i, irq; struct mmphw_path_plat *path_plat; struct mmphw_ctrl *ctrl = NULL; @@ -461,9 +461,9 @@ static int mmphw_probe(struct platform_device *pdev) } /* allocate */ - size = sizeof(struct mmphw_ctrl) + sizeof(struct mmphw_path_plat) * - mi->path_num; - ctrl = devm_kzalloc(&pdev->dev, size, GFP_KERNEL); + ctrl = devm_kzalloc(&pdev->dev, + struct_size(ctrl, path_plats, mi->path_num), + GFP_KERNEL); if (!ctrl) { ret = -ENOMEM; goto failed; -- 2.21.0