From patchwork Wed Aug 24 16:03:48 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lukas Czerner X-Patchwork-Id: 12953778 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0D6BAC32792 for ; Wed, 24 Aug 2022 16:04:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239190AbiHXQEC (ORCPT ); Wed, 24 Aug 2022 12:04:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49262 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239169AbiHXQD7 (ORCPT ); Wed, 24 Aug 2022 12:03:59 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 846607D1E4 for ; Wed, 24 Aug 2022 09:03:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1661357037; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=crooFDsd/t/C+VmO2GlK18gRr5taZHHgJKYwO/+fySQ=; b=YY8RFXXmsJUPQWXWEheLO097OdZEGJzV8ZRIxNkxW/aw2ZHcOYGsjhOoKDo1SRJl0ZjHIf MDrU+ipX0oU/PQjr+LDa+X06Ndye2hpXvqDQGIiYvpJjAQVWWihLcC/o/f3q8LsvrIjP0R 2sxsCSTBTieW4W/Apv1H6f8BxUTZmp4= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-151-DDeSvD2YOU2VdvFj000x-w-1; Wed, 24 Aug 2022 12:03:54 -0400 X-MC-Unique: DDeSvD2YOU2VdvFj000x-w-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 98D1F805B9A; Wed, 24 Aug 2022 16:03:53 +0000 (UTC) Received: from fedora.redhat.com (unknown [10.40.193.195]) by smtp.corp.redhat.com (Postfix) with ESMTP id 3408B492C3B; Wed, 24 Aug 2022 16:03:52 +0000 (UTC) From: Lukas Czerner To: linux-ext4@vger.kernel.org Cc: tytso@mit.edu, jlayton@kernel.org, jack@suse.cz, linux-fsdevel@vger.kernel.org, ebiggers@kernel.org, david@fromorbit.com, Christoph Hellwig Subject: [PATCH v4 2/3] fs: record I_DIRTY_TIME even if inode already has I_DIRTY_INODE Date: Wed, 24 Aug 2022 18:03:48 +0200 Message-Id: <20220824160349.39664-2-lczerner@redhat.com> In-Reply-To: <20220824160349.39664-1-lczerner@redhat.com> References: <20220824160349.39664-1-lczerner@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.85 on 10.11.54.9 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org Currently the I_DIRTY_TIME will never get set if the inode already has I_DIRTY_INODE with assumption that it supersedes I_DIRTY_TIME. That's true, however ext4 will only update the on-disk inode in ->dirty_inode(), not on actual writeback. As a result if the inode already has I_DIRTY_INODE state by the time we get to __mark_inode_dirty() only with I_DIRTY_TIME, the time was already filled into on-disk inode and will not get updated until the next I_DIRTY_INODE update, which might never come if we crash or get a power failure. The problem can be reproduced on ext4 by running xfstest generic/622 with -o iversion mount option. Fix it by allowing I_DIRTY_TIME to be set even if the inode already has I_DIRTY_INODE. Also make sure that the case is properly handled in writeback_single_inode() as well. Additionally changes in xfs_fs_dirty_inode() was made to accommodate for I_DIRTY_TIME in flag. Thanks Jan Kara for suggestions on how to make this work properly. Cc: Dave Chinner Cc: Christoph Hellwig Signed-off-by: Lukas Czerner Suggested-by: Jan Kara Reviewed-by: Jan Kara --- v2: Reworked according to suggestions from Jan v3: Update documentation, add comments, change flag to flags in xfs_fs_dirty_inode() v4: Update documentation, simplify condition in xfs_fs_dirty_inode() Documentation/filesystems/vfs.rst | 3 +++ fs/fs-writeback.c | 34 ++++++++++++++++++++----------- fs/xfs/xfs_super.c | 10 +++++++-- include/linux/fs.h | 9 ++++---- 4 files changed, 38 insertions(+), 18 deletions(-) diff --git a/Documentation/filesystems/vfs.rst b/Documentation/filesystems/vfs.rst index 6cd6953e175b..b2ef2449aed9 100644 --- a/Documentation/filesystems/vfs.rst +++ b/Documentation/filesystems/vfs.rst @@ -274,6 +274,9 @@ or bottom half). This is specifically for the inode itself being marked dirty, not its data. If the update needs to be persisted by fdatasync(), then I_DIRTY_DATASYNC will be set in the flags argument. + I_DIRTY_TIME will be set in the flags in case lazytime is enabled + and struct inode has times updated since the last ->dirty_inode + call. ``write_inode`` this method is called when the VFS needs to write an inode to diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c index 05221366a16d..638dbf143727 100644 --- a/fs/fs-writeback.c +++ b/fs/fs-writeback.c @@ -1718,9 +1718,14 @@ static int writeback_single_inode(struct inode *inode, */ if (!(inode->i_state & I_DIRTY_ALL)) inode_cgwb_move_to_attached(inode, wb); - else if (!(inode->i_state & I_SYNC_QUEUED) && - (inode->i_state & I_DIRTY)) - redirty_tail_locked(inode, wb); + else if (!(inode->i_state & I_SYNC_QUEUED)) { + if ((inode->i_state & I_DIRTY)) + redirty_tail_locked(inode, wb); + else if (inode->i_state & I_DIRTY_TIME) { + inode->dirtied_when = jiffies; + inode_io_list_move_locked(inode, wb, &wb->b_dirty_time); + } + } spin_unlock(&wb->list_lock); inode_sync_complete(inode); @@ -2369,6 +2374,17 @@ void __mark_inode_dirty(struct inode *inode, int flags) trace_writeback_mark_inode_dirty(inode, flags); if (flags & I_DIRTY_INODE) { + + /* Inode timestamp update will piggback on this dirtying */ + if (inode->i_state & I_DIRTY_TIME) { + spin_lock(&inode->i_lock); + if (inode->i_state & I_DIRTY_TIME) { + inode->i_state &= ~I_DIRTY_TIME; + flags |= I_DIRTY_TIME; + } + spin_unlock(&inode->i_lock); + } + /* * Notify the filesystem about the inode being dirtied, so that * (if needed) it can update on-disk fields and journal the @@ -2378,7 +2394,8 @@ void __mark_inode_dirty(struct inode *inode, int flags) */ trace_writeback_dirty_inode_start(inode, flags); if (sb->s_op->dirty_inode) - sb->s_op->dirty_inode(inode, flags & I_DIRTY_INODE); + sb->s_op->dirty_inode(inode, + flags & (I_DIRTY_INODE | I_DIRTY_TIME)); trace_writeback_dirty_inode(inode, flags); /* I_DIRTY_INODE supersedes I_DIRTY_TIME. */ @@ -2399,21 +2416,15 @@ void __mark_inode_dirty(struct inode *inode, int flags) */ smp_mb(); - if (((inode->i_state & flags) == flags) || - (dirtytime && (inode->i_state & I_DIRTY_INODE))) + if ((inode->i_state & flags) == flags) return; spin_lock(&inode->i_lock); - if (dirtytime && (inode->i_state & I_DIRTY_INODE)) - goto out_unlock_inode; if ((inode->i_state & flags) != flags) { const int was_dirty = inode->i_state & I_DIRTY; inode_attach_wb(inode, NULL); - /* I_DIRTY_INODE supersedes I_DIRTY_TIME. */ - if (flags & I_DIRTY_INODE) - inode->i_state &= ~I_DIRTY_TIME; inode->i_state |= flags; /* @@ -2486,7 +2497,6 @@ void __mark_inode_dirty(struct inode *inode, int flags) out_unlock: if (wb) spin_unlock(&wb->list_lock); -out_unlock_inode: spin_unlock(&inode->i_lock); } EXPORT_SYMBOL(__mark_inode_dirty); diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c index 9ac59814bbb6..f029c6702dda 100644 --- a/fs/xfs/xfs_super.c +++ b/fs/xfs/xfs_super.c @@ -653,7 +653,7 @@ xfs_fs_destroy_inode( static void xfs_fs_dirty_inode( struct inode *inode, - int flag) + int flags) { struct xfs_inode *ip = XFS_I(inode); struct xfs_mount *mp = ip->i_mount; @@ -661,7 +661,13 @@ xfs_fs_dirty_inode( if (!(inode->i_sb->s_flags & SB_LAZYTIME)) return; - if (flag != I_DIRTY_SYNC || !(inode->i_state & I_DIRTY_TIME)) + + /* + * Only do the timestamp update if the inode is dirty (I_DIRTY_SYNC) + * and has dirty timestamp (I_DIRTY_TIME). I_DIRTY_TIME can be passed + * in flags possibly together with I_DIRTY_SYNC. + */ + if ((flags & ~I_DIRTY_TIME) != I_DIRTY_SYNC || !(flags & I_DIRTY_TIME)) return; if (xfs_trans_alloc(mp, &M_RES(mp)->tr_fsyncts, 0, 0, 0, &tp)) diff --git a/include/linux/fs.h b/include/linux/fs.h index 9eced4cc286e..56a4b4b02477 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2371,13 +2371,14 @@ static inline void kiocb_clone(struct kiocb *kiocb, struct kiocb *kiocb_src, * don't have to write inode on fdatasync() when only * e.g. the timestamps have changed. * I_DIRTY_PAGES Inode has dirty pages. Inode itself may be clean. - * I_DIRTY_TIME The inode itself only has dirty timestamps, and the + * I_DIRTY_TIME The inode itself has dirty timestamps, and the * lazytime mount option is enabled. We keep track of this * separately from I_DIRTY_SYNC in order to implement * lazytime. This gets cleared if I_DIRTY_INODE - * (I_DIRTY_SYNC and/or I_DIRTY_DATASYNC) gets set. I.e. - * either I_DIRTY_TIME *or* I_DIRTY_INODE can be set in - * i_state, but not both. I_DIRTY_PAGES may still be set. + * (I_DIRTY_SYNC and/or I_DIRTY_DATASYNC) gets set. But + * I_DIRTY_TIME can still be set if I_DIRTY_SYNC is already + * in place because writeback might already be in progress + * and we don't want to lose the time update * I_NEW Serves as both a mutex and completion notification. * New inodes set I_NEW. If two processes both create * the same inode, one of them will release its inode and