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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 773BBC6778C for ; Sun, 1 Jul 2018 19:29:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F0C73256AB for ; Sun, 1 Jul 2018 19:29:43 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F0C73256AB Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=ZenIV.linux.org.uk Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752582AbeGAT3m (ORCPT ); Sun, 1 Jul 2018 15:29:42 -0400 Received: from zeniv.linux.org.uk ([195.92.253.2]:60940 "EHLO ZenIV.linux.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752433AbeGAT3j (ORCPT ); Sun, 1 Jul 2018 15:29:39 -0400 Received: from viro by ZenIV.linux.org.uk with local (Exim 4.87 #1 (Red Hat Linux)) id 1fZhyy-0008PD-Vj; Sun, 01 Jul 2018 19:26:01 +0000 Date: Sun, 1 Jul 2018 20:26:00 +0100 From: Al Viro To: Huaisheng Ye Cc: dan.j.williams@intel.com, dave.jiang@intel.com, willy@infradead.org, ross.zwisler@linux.intel.com, vishal.l.verma@intel.com, jack@suse.com, chengnt@lenovo.com, linux-nvdimm@lists.01.org, linux-kernel@vger.kernel.org, linux-ext4@vger.kernel.org, Huaisheng Ye Subject: Re: [PATCH 2/3] fs/ext2/inode: Fix a type cast error for fsdax Message-ID: <20180701192600.GT30522@ZenIV.linux.org.uk> References: <20180701061848.7036-1-yehs2007@zoho.com> <20180701061848.7036-2-yehs2007@zoho.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180701061848.7036-2-yehs2007@zoho.com> User-Agent: Mutt/1.9.1 (2017-09-22) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Jul 01, 2018 at 02:18:47PM +0800, Huaisheng Ye wrote: > From: Huaisheng Ye > > The type of offset within struct iomap is loff_t, which represents > file offset of mapping. > > In ext2_iomap_begin, iomap->offset shall be given a type cast as > loff_t instead of u64. Why is it an error? loff_t is uniformly typedefed to long long. In which case the second variant is different from the first one *and* does not step into nasal demon territory? > - iomap->offset = (u64)first_block << blkbits; > + iomap->offset = (loff_t)first_block << blkbits;