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=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 0D7AFC433DB for ; Thu, 25 Feb 2021 07:47:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B85D464E20 for ; Thu, 25 Feb 2021 07:47:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235037AbhBYHrk (ORCPT ); Thu, 25 Feb 2021 02:47:40 -0500 Received: from verein.lst.de ([213.95.11.211]:40562 "EHLO verein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233137AbhBYHrg (ORCPT ); Thu, 25 Feb 2021 02:47:36 -0500 Received: by verein.lst.de (Postfix, from userid 2407) id D893868B05; Thu, 25 Feb 2021 08:35:25 +0100 (CET) Date: Thu, 25 Feb 2021 08:35:25 +0100 From: Christoph Hellwig To: "Darrick J. Wong" Cc: Ruan Shiyang , Christoph Hellwig , linux-kernel@vger.kernel.org, linux-xfs@vger.kernel.org, linux-nvdimm@lists.01.org, linux-fsdevel@vger.kernel.org, darrick.wong@oracle.com, dan.j.williams@intel.com, willy@infradead.org, jack@suse.cz, viro@zeniv.linux.org.uk, linux-btrfs@vger.kernel.org, ocfs2-devel@oss.oracle.com, david@fromorbit.com, rgoldwyn@suse.de, Goldwyn Rodrigues Subject: Re: [PATCH 5/7] fsdax: Dedup file range to use a compare function Message-ID: <20210225073525.GA3448@lst.de> References: <20210207170924.2933035-1-ruansy.fnst@cn.fujitsu.com> <20210207170924.2933035-6-ruansy.fnst@cn.fujitsu.com> <20210208151920.GE12872@lst.de> <9193e305-22a1-3928-0675-af1cecd28942@cn.fujitsu.com> <20210209093438.GA630@lst.de> <79b0d65c-95dd-4821-e412-ab27c8cb6942@cn.fujitsu.com> <20210210131928.GA30109@lst.de> <20210218162018.GT7193@magnolia> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210218162018.GT7193@magnolia> User-Agent: Mutt/1.5.17 (2007-11-01) Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Thu, Feb 18, 2021 at 08:20:18AM -0800, Darrick J. Wong wrote: > > I think a nested call like this is necessary. That's why I use the open > > code way. > > This might be a good place to implement an iomap_apply2() loop that > actually /does/ walk all the extents of file1 and file2. There's now > two users of this idiom. Why do we need a special helper for that? > (Possibly structured as a "get next mappings from both" generator > function like Matthew Wilcox keeps asking for. :)) OTOH this might be a good first use for that.