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=-8.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,UNPARSEABLE_RELAY 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 95D15C07E9D for ; Mon, 19 Jul 2021 15:29:46 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0A61060FED for ; Mon, 19 Jul 2021 15:29:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0A61060FED Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linux-erofs-bounces+linux-erofs=archiver.kernel.org@lists.ozlabs.org Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4GT5PN5Hm5z30HK for ; Tue, 20 Jul 2021 01:29:44 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=linux.alibaba.com (client-ip=115.124.30.133; helo=out30-133.freemail.mail.aliyun.com; envelope-from=hsiangkao@linux.alibaba.com; receiver=) Received: from out30-133.freemail.mail.aliyun.com (out30-133.freemail.mail.aliyun.com [115.124.30.133]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4GT5PH4P90z302g for ; Tue, 20 Jul 2021 01:29:37 +1000 (AEST) X-Alimail-AntiSpam: AC=PASS; BC=-1|-1; BR=01201311R121e4; CH=green; DM=||false|; DS=||; FP=0|-1|-1|-1|0|-1|-1|-1; HT=e01e04394; MF=hsiangkao@linux.alibaba.com; NM=1; PH=DS; RN=7; SR=0; TI=SMTPD_---0UgI5qI7_1626708560; Received: from B-P7TQMD6M-0146.local(mailfrom:hsiangkao@linux.alibaba.com fp:SMTPD_---0UgI5qI7_1626708560) by smtp.aliyun-inc.com(127.0.0.1); Mon, 19 Jul 2021 23:29:22 +0800 Date: Mon, 19 Jul 2021 23:29:20 +0800 From: Gao Xiang To: Matthew Wilcox Subject: Re: [PATCH v3] iomap: support tail packing inline read Message-ID: Mail-Followup-To: Matthew Wilcox , linux-erofs@lists.ozlabs.org, linux-fsdevel@vger.kernel.org, LKML , Christoph Hellwig , "Darrick J . Wong" , Andreas Gruenbacher References: <20210719144747.189634-1-hsiangkao@linux.alibaba.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: X-BeenThere: linux-erofs@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Development of Linux EROFS file system List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "Darrick J . Wong" , Andreas Gruenbacher , LKML , linux-fsdevel@vger.kernel.org, linux-erofs@lists.ozlabs.org, Christoph Hellwig Errors-To: linux-erofs-bounces+linux-erofs=archiver.kernel.org@lists.ozlabs.org Sender: "Linux-erofs" On Mon, Jul 19, 2021 at 04:02:30PM +0100, Matthew Wilcox wrote: > On Mon, Jul 19, 2021 at 10:47:47PM +0800, Gao Xiang wrote: > > @@ -246,18 +245,19 @@ iomap_readpage_actor(struct inode *inode, loff_t pos, loff_t length, void *data, > > unsigned poff, plen; > > sector_t sector; > > > > - if (iomap->type == IOMAP_INLINE) { > > - WARN_ON_ONCE(pos); > > - iomap_read_inline_data(inode, page, iomap); > > - return PAGE_SIZE; > > - } > > - > > - /* zero post-eof blocks as the page may be mapped */ > > iop = iomap_page_create(inode, page); > > + /* needs to skip some leading uptodated blocks */ > > iomap_adjust_read_range(inode, iop, &pos, length, &poff, &plen); > > if (plen == 0) > > goto done; > > > > + if (iomap->type == IOMAP_INLINE) { > > + iomap_read_inline_data(inode, page, iomap, pos); > > + plen = PAGE_SIZE - poff; > > + goto done; > > + } > > This is going to break Andreas' case that he just patched to work. > GFS2 needs for there to _not_ be an iop for inline data. That's > why I said we need to sort out when to create an iop before moving > the IOMAP_INLINE case below the creation of the iop. I have no idea how it breaks Andreas' case from the previous commit message: " iomap: Don't create iomap_page objects for inline files In iomap_readpage_actor, don't create iop objects for inline inodes. Otherwise, iomap_read_inline_data will set PageUptodate without setting iop->uptodate, and iomap_page_release will eventually complain. To prevent this kind of bug from occurring in the future, make sure the page doesn't have private data attached in iomap_read_inline_data. " After this patch, iomap_read_inline_data() will set iop->uptodate with iomap_set_range_uptodate() rather than set PageUptodate() directly, so iomap_page_release won't complain. Am I missing something? Thanks, Gao Xiang > > If we're not going to do that first, then I recommend leaving the > IOMAP_INLINE case where it is and changing it to ... > > if (iomap->type == IOMAP_INLINE) > return iomap_read_inline_data(inode, page, iomap, pos); > > ... and have iomap_read_inline_data() return the number of bytes that > it copied + zeroed (ie PAGE_SIZE - poff).