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_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 C775FC43387 for ; Mon, 24 Dec 2018 06:52:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8FA1221736 for ; Mon, 24 Dec 2018 06:52:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726720AbeLXGwV (ORCPT ); Mon, 24 Dec 2018 01:52:21 -0500 Received: from gateway21.websitewelcome.com ([192.185.45.38]:22937 "EHLO gateway21.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725922AbeLXGwV (ORCPT ); Mon, 24 Dec 2018 01:52:21 -0500 Received: from cm13.websitewelcome.com (cm13.websitewelcome.com [100.42.49.6]) by gateway21.websitewelcome.com (Postfix) with ESMTP id 0194B400CD7BC for ; Mon, 24 Dec 2018 00:52:20 -0600 (CST) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id bK67gtXyhYTGMbK67gi1OL; Mon, 24 Dec 2018 00:52:19 -0600 X-Authority-Reason: nr=8 Received: from [189.250.106.44] (port=50146 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.91) (envelope-from ) id 1gbK67-000NqL-1s; Mon, 24 Dec 2018 00:52:19 -0600 Date: Mon, 24 Dec 2018 00:52:17 -0600 From: "Gustavo A. R. Silva" To: Zubair Lutfullah Kakakhel , Dan Williams , Vinod Koul Cc: dmaengine@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH] dmaengine: dma-jz4780: Use struct_size() in devm_kzalloc() Message-ID: <20181224065217.GA10629@embeddedor.com> 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: 189.250.106.44 X-Source-L: No X-Exim-ID: 1gbK67-000NqL-1s X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [189.250.106.44]:50146 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 19 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; 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 issue was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva --- drivers/dma/dma-jz4780.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/dma/dma-jz4780.c b/drivers/dma/dma-jz4780.c index a8b6225faa12..9ce0a386225b 100644 --- a/drivers/dma/dma-jz4780.c +++ b/drivers/dma/dma-jz4780.c @@ -838,9 +838,8 @@ static int jz4780_dma_probe(struct platform_device *pdev) if (!soc_data) return -EINVAL; - jzdma = devm_kzalloc(dev, sizeof(*jzdma) - + sizeof(*jzdma->chan) * soc_data->nb_channels, - GFP_KERNEL); + jzdma = devm_kzalloc(dev, struct_size(jzdma, chan, + soc_data->nb_channels), GFP_KERNEL); if (!jzdma) return -ENOMEM; -- 2.20.1