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, 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 DEB22C28CC5 for ; Wed, 5 Jun 2019 20:21:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BE00E2070B for ; Wed, 5 Jun 2019 20:21:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726671AbfFEUVl (ORCPT ); Wed, 5 Jun 2019 16:21:41 -0400 Received: from gateway34.websitewelcome.com ([192.185.148.164]:20754 "EHLO gateway34.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726501AbfFEUVk (ORCPT ); Wed, 5 Jun 2019 16:21:40 -0400 Received: from cm17.websitewelcome.com (cm17.websitewelcome.com [100.42.49.20]) by gateway34.websitewelcome.com (Postfix) with ESMTP id ABDD9C7B01 for ; Wed, 5 Jun 2019 15:00:08 -0500 (CDT) Received: from gator4166.hostgator.com ([108.167.133.22]) by cmsmtp with SMTP id Yc4uh2vtu90onYc4uh4cOL; Wed, 05 Jun 2019 15:00:08 -0500 X-Authority-Reason: nr=8 Received: from [189.250.127.120] (port=32980 helo=embeddedor) by gator4166.hostgator.com with esmtpa (Exim 4.91) (envelope-from ) id 1hYc4t-003gcA-Jz; Wed, 05 Jun 2019 15:00:07 -0500 Date: Wed, 5 Jun 2019 15:00:02 -0500 From: "Gustavo A. R. Silva" To: Kamil Debski , Sylwester Nawrocki , Kishon Vijay Abraham I Cc: linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH] phy: samsung: Use struct_size() in devm_kzalloc() Message-ID: <20190605200002.GA18640@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: 1hYc4t-003gcA-Jz X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedor) [189.250.127.120]:32980 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 4 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 samsung_usb2_phy_driver { ... struct samsung_usb2_phy_instance instances[0]; }; instance = devm_kzalloc(dev, sizeof(struct samsung_usb2_phy_driver) + count * sizeof(struct samsung_usb2_phy_instance), 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, instances, count), GFP_KERNEL); This code was detected with the help of Coccinelle. Signed-off-by: Gustavo A. R. Silva --- drivers/phy/samsung/phy-samsung-usb2.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/phy/samsung/phy-samsung-usb2.c b/drivers/phy/samsung/phy-samsung-usb2.c index ea818866985a..4616ec829900 100644 --- a/drivers/phy/samsung/phy-samsung-usb2.c +++ b/drivers/phy/samsung/phy-samsung-usb2.c @@ -159,9 +159,8 @@ static int samsung_usb2_phy_probe(struct platform_device *pdev) if (!cfg) return -EINVAL; - drv = devm_kzalloc(dev, sizeof(struct samsung_usb2_phy_driver) + - cfg->num_phys * sizeof(struct samsung_usb2_phy_instance), - GFP_KERNEL); + drv = devm_kzalloc(dev, struct_size(drv, instances, cfg->num_phys), + GFP_KERNEL); if (!drv) return -ENOMEM; -- 2.21.0