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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 14F6CC10F29 for ; Wed, 11 Mar 2020 12:58:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E9D532146E for ; Wed, 11 Mar 2020 12:58:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729383AbgCKM6D (ORCPT ); Wed, 11 Mar 2020 08:58:03 -0400 Received: from outgoing-auth-1.mit.edu ([18.9.28.11]:40659 "EHLO outgoing.mit.edu" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1729331AbgCKM6C (ORCPT ); Wed, 11 Mar 2020 08:58:02 -0400 Received: from callcc.thunk.org (pool-72-93-95-157.bstnma.fios.verizon.net [72.93.95.157]) (authenticated bits=0) (User authenticated as tytso@ATHENA.MIT.EDU) by outgoing.mit.edu (8.14.7/8.12.4) with ESMTP id 02BCvnk4017660 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 11 Mar 2020 08:57:49 -0400 Received: by callcc.thunk.org (Postfix, from userid 15806) id 3D70A42045B; Wed, 11 Mar 2020 08:57:49 -0400 (EDT) Date: Wed, 11 Mar 2020 08:57:49 -0400 From: "Theodore Y. Ts'o" To: Eric Biggers Cc: Linux Filesystem Development List , Ext4 Developers List , linux-f2fs-devel@lists.sourceforge.net Subject: Re: [PATCH] writeback: avoid double-writing the inode on a lazytime expiration Message-ID: <20200311125749.GA7159@mit.edu> References: <20200306004555.GB225345@gmail.com> <20200307020043.60118-1-tytso@mit.edu> <20200311032009.GC46757@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200311032009.GC46757@gmail.com> Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Tue, Mar 10, 2020 at 08:20:09PM -0700, Eric Biggers wrote: > Thanks Ted! This fixes the fscrypt test failure. > > However, are you sure this works correctly on all filesystems? I'm not sure > about XFS. XFS only implements ->dirty_inode(), not ->write_inode(), and in its > ->dirty_inode() it does: ... > if (flag != I_DIRTY_SYNC || !(inode->i_state & I_DIRTY_TIME)) > return; That's true, but when the timestamps were originally modified, dirty_inode() will be called with flag == I_DIRTY_TIME, which will *not* be a no-op; which is to say, XFS will force the timestamps to be updated on disk when the timestamps are first dirtied, because it doesn't support I_DIRTY_TIME. So I think we're fine. - Ted 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=-0.6 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 ECE82C10F27 for ; Wed, 11 Mar 2020 12:58:02 +0000 (UTC) Received: from lists.sourceforge.net (lists.sourceforge.net [216.105.38.7]) (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 AED842146E; Wed, 11 Mar 2020 12:58:02 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=sourceforge.net header.i=@sourceforge.net header.b="UNrIRVOb"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=sf.net header.i=@sf.net header.b="SAspNr9z" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org AED842146E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=mit.edu Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linux-f2fs-devel-bounces@lists.sourceforge.net Received: from [127.0.0.1] (helo=sfs-ml-4.v29.lw.sourceforge.com) by sfs-ml-4.v29.lw.sourceforge.com with esmtp (Exim 4.90_1) (envelope-from ) id 1jC0vy-0002vC-4O; Wed, 11 Mar 2020 12:58:02 +0000 Received: from [172.30.20.202] (helo=mx.sourceforge.net) by sfs-ml-4.v29.lw.sourceforge.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jC0vw-0002ut-El for linux-f2fs-devel@lists.sourceforge.net; Wed, 11 Mar 2020 12:58:00 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sourceforge.net; s=x; h=In-Reply-To:Content-Type:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=IaROnpcjebfXREevgmU63GBuXUtavi+CZTDQYlg8YYM=; b=UNrIRVObXgl7JILp+PIyn/Sfrj 1soacRJMQtAXxBTL9d9r/FGzxgJCR2SKSrLijJ+MXFvd3nU7SfvKgbATznLc05dzuMSBDbzZ02Avq TegIobvc1TV+2ew/YA8QiZAiCA91QCE/3QX18xAdFDu3LOuChtz8Gz/qFhYBQmXUsxIg=; DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sf.net; s=x ; h=In-Reply-To:Content-Type:MIME-Version:References:Message-ID:Subject:Cc:To :From:Date:Sender:Reply-To:Content-Transfer-Encoding:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=IaROnpcjebfXREevgmU63GBuXUtavi+CZTDQYlg8YYM=; b=SAspNr9z49qHPU+EfsE39pXwhe L25Ex5foITvdAENvSXyiZh6/z4b2a+j6yJvfGb31H1SWr5/QNsithwOTiiQyoCiAmWMvjXWaPHn85 3afEkFjSZWEbcRJsQYpTHr6sz3/U5MC5BTGpKLXRRSVaor0es7mdOpEapH6yL/49mMTo=; Received: from outgoing-auth-1.mit.edu ([18.9.28.11] helo=outgoing.mit.edu) by sfi-mx-4.v28.lw.sourceforge.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.92.2) id 1jC0vu-008PnU-Ck for linux-f2fs-devel@lists.sourceforge.net; Wed, 11 Mar 2020 12:58:00 +0000 Received: from callcc.thunk.org (pool-72-93-95-157.bstnma.fios.verizon.net [72.93.95.157]) (authenticated bits=0) (User authenticated as tytso@ATHENA.MIT.EDU) by outgoing.mit.edu (8.14.7/8.12.4) with ESMTP id 02BCvnk4017660 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 11 Mar 2020 08:57:49 -0400 Received: by callcc.thunk.org (Postfix, from userid 15806) id 3D70A42045B; Wed, 11 Mar 2020 08:57:49 -0400 (EDT) Date: Wed, 11 Mar 2020 08:57:49 -0400 From: "Theodore Y. Ts'o" To: Eric Biggers Message-ID: <20200311125749.GA7159@mit.edu> References: <20200306004555.GB225345@gmail.com> <20200307020043.60118-1-tytso@mit.edu> <20200311032009.GC46757@gmail.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200311032009.GC46757@gmail.com> X-Headers-End: 1jC0vu-008PnU-Ck Subject: Re: [f2fs-dev] [PATCH] writeback: avoid double-writing the inode on a lazytime expiration X-BeenThere: linux-f2fs-devel@lists.sourceforge.net X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Linux Filesystem Development List , Ext4 Developers List , linux-f2fs-devel@lists.sourceforge.net Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net On Tue, Mar 10, 2020 at 08:20:09PM -0700, Eric Biggers wrote: > Thanks Ted! This fixes the fscrypt test failure. > > However, are you sure this works correctly on all filesystems? I'm not sure > about XFS. XFS only implements ->dirty_inode(), not ->write_inode(), and in its > ->dirty_inode() it does: ... > if (flag != I_DIRTY_SYNC || !(inode->i_state & I_DIRTY_TIME)) > return; That's true, but when the timestamps were originally modified, dirty_inode() will be called with flag == I_DIRTY_TIME, which will *not* be a no-op; which is to say, XFS will force the timestamps to be updated on disk when the timestamps are first dirtied, because it doesn't support I_DIRTY_TIME. So I think we're fine. - Ted _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel