From patchwork Tue Jun 4 23:32:05 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: 10976229 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 A056B92A for ; Tue, 4 Jun 2019 23:54:48 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8BCF02859F for ; Tue, 4 Jun 2019 23:54:48 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 7D1EF28882; Tue, 4 Jun 2019 23:54:48 +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 274832859F for ; Tue, 4 Jun 2019 23:54:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726427AbfFDXyr (ORCPT ); Tue, 4 Jun 2019 19:54:47 -0400 Received: from gateway34.websitewelcome.com ([192.185.148.164]:44495 "EHLO gateway34.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726317AbfFDXyr (ORCPT ); Tue, 4 Jun 2019 19:54:47 -0400 X-Greylist: delayed 1359 seconds by postgrey-1.27 at vger.kernel.org; Tue, 04 Jun 2019 19:54:47 EDT Received: from cm10.websitewelcome.com (cm10.websitewelcome.com [100.42.49.4]) by gateway34.websitewelcome.com (Postfix) with ESMTP id B0855615C7 for ; Tue, 4 Jun 2019 18:32:07 -0500 (CDT) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id YIuVhQtVZ2PzOYIuVhlSca; 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-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: 13 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes Sender: linux-fbdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fbdev@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 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;