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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT 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 B5A41C10DCE for ; Sat, 7 Mar 2020 02:01:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8907A206CC for ; Sat, 7 Mar 2020 02:01:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726307AbgCGCBN (ORCPT ); Fri, 6 Mar 2020 21:01:13 -0500 Received: from outgoing-auth-1.mit.edu ([18.9.28.11]:52494 "EHLO outgoing.mit.edu" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726231AbgCGCBN (ORCPT ); Fri, 6 Mar 2020 21:01:13 -0500 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 02720trO015135 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Fri, 6 Mar 2020 21:00:55 -0500 Received: by callcc.thunk.org (Postfix, from userid 15806) id 4FE0242045B; Fri, 6 Mar 2020 21:00:54 -0500 (EST) From: "Theodore Ts'o" To: Linux Filesystem Development List Cc: Ext4 Developers List , linux-f2fs-devel@lists.sourceforge.net, "Theodore Ts'o" , Eric Biggers Subject: [PATCH] writeback: avoid double-writing the inode on a lazytime expiration Date: Fri, 6 Mar 2020 21:00:43 -0500 Message-Id: <20200307020043.60118-1-tytso@mit.edu> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200306004555.GB225345@gmail.com> References: <20200306004555.GB225345@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org In the case that an inode has dirty timestamp for longer than the lazytime expiration timeout (or if all such inodes are being flushed out due to a sync or syncfs system call), we need to inform the file system that the inode is dirty so that the inode's timestamps can be copied out to the on-disk data structures. That's because if the file system supports lazytime, it will have ignored the dirty_inode(inode, I_DIRTY_TIME) notification when the timestamp was modified in memory.q Previously, this was accomplished by calling mark_inode_dirty_sync(), but that has the unfortunate side effect of also putting the inode the writeback list, and that's not necessary in this case, since we will immediately call write_inode() afterwards. Eric Biggers noticed that this was causing problems for fscrypt after the key was removed[1]. [1] https://lore.kernel.org/r/20200306004555.GB225345@gmail.com Reported-by: Eric Biggers Signed-off-by: Theodore Ts'o --- fs/fs-writeback.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 76ac9c7d32ec..32101349ba97 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -1504,8 +1504,9 @@ __writeback_single_inode(struct inode *inode, struct writeback_control *wbc) spin_unlock(&inode->i_lock); - if (dirty & I_DIRTY_TIME) - mark_inode_dirty_sync(inode); + /* This was a lazytime expiration; we need to tell the file system */ + if (dirty & I_DIRTY_TIME_EXPIRED && inode->i_sb->s_op->dirty_inode) + inode->i_sb->s_op->dirty_inode(inode, I_DIRTY_TIME_EXPIRED); /* Don't write the inode if only I_DIRTY_PAGES was set */ if (dirty & ~I_DIRTY_PAGES) { int err = write_inode(inode, wbc); -- 2.24.1