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=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 9779AC433B4 for ; Fri, 9 Apr 2021 13:45:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 691ED6113A for ; Fri, 9 Apr 2021 13:45:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233137AbhDINpz (ORCPT ); Fri, 9 Apr 2021 09:45:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47092 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232642AbhDINpy (ORCPT ); Fri, 9 Apr 2021 09:45:54 -0400 Received: from mail-vs1-xe2c.google.com (mail-vs1-xe2c.google.com [IPv6:2607:f8b0:4864:20::e2c]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 899FEC061760 for ; Fri, 9 Apr 2021 06:45:40 -0700 (PDT) Received: by mail-vs1-xe2c.google.com with SMTP id r12so2945126vsj.5 for ; Fri, 09 Apr 2021 06:45:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=szeredi.hu; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=mjbwxZLTfyMvTIAAB3KJizD/ANM3CPP2Lc59q5rRawA=; b=aK3LXwbfJM2K86PfIVmS+h8V2lnVkHYNWItFNMT69Df3a2+Wrr989fA0r9IDHxK8Ln q0w74EW69gHu5m1XJh8+vT9qu2ewcGlYx1qG9YtAbscQVVooitjjmbifJOMXqgQtb0t7 BtdTCTF/UOynKIH9zqRXbL/1kU7pdWTFwT/8g= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=mjbwxZLTfyMvTIAAB3KJizD/ANM3CPP2Lc59q5rRawA=; b=LFv3WU0a896Ai2hkr658rbu0LReW+fqzONkCVJ5KukjFXZwkts6AmW7bXPCRxWAhpI J4t5VpHRJmIJ2VPXtuP0GStql8SQKpdwp9R4W/e+OXlmSBAfiAQvmgOtITI3B8C2sK3h KpfI4LUN7tuWIuiOHjwHGDyHLkxOr7PM5JrFlXkAXGqGw6pIQK4VcF8hLfty0UsiUybz MQBj+2pLy3uAH3ILAEJnL55ykt3gx88XV4YCXP2uwYHsXTt7qsxseik3vuftc+872Zrb pitwMhf7hbQyzbbCY4KBrBIhTeuu3jX9QVwzMZEesFCE4gKRLORkvkQa10tJg03ZpPlg x4mw== X-Gm-Message-State: AOAM530k9XSkpo7xSzOoA5eooIXHSS7v7WSramrg67tnq++Tfgv1To5S OySc1Y5mi4/tW9bg6XCZ11KBh9Gz/VbTIGeJtXQ0/g== X-Google-Smtp-Source: ABdhPJziNwqoXOHIqKtY2+xBsszR+39euUQGGGVXqZL9/ApN4CYJ8ffPcQYBBU+BpCpC6VPiwz3yQim8PQNBJmy/hWA= X-Received: by 2002:a67:f487:: with SMTP id o7mr11175315vsn.7.1617975939801; Fri, 09 Apr 2021 06:45:39 -0700 (PDT) MIME-Version: 1.0 References: <20201113065555.147276-1-cgxu519@mykernel.net> <20201113065555.147276-5-cgxu519@mykernel.net> In-Reply-To: <20201113065555.147276-5-cgxu519@mykernel.net> From: Miklos Szeredi Date: Fri, 9 Apr 2021 15:45:28 +0200 Message-ID: Subject: Re: [RFC PATCH v4 4/9] ovl: mark overlayfs' inode dirty on modification To: Chengguang Xu Cc: Jan Kara , Amir Goldstein , overlayfs , linux-fsdevel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Fri, Nov 13, 2020 at 7:57 AM Chengguang Xu wrote: > > Mark overlayfs' inode dirty on modification so that > we can recognize target inodes during syncfs. > > Signed-off-by: Chengguang Xu > --- > fs/overlayfs/inode.c | 1 + > fs/overlayfs/overlayfs.h | 4 ++++ > fs/overlayfs/util.c | 14 ++++++++++++++ > 3 files changed, 19 insertions(+) > > diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c > index 8cfa75e86f56..342693657ab0 100644 > --- a/fs/overlayfs/inode.c > +++ b/fs/overlayfs/inode.c > @@ -468,6 +468,7 @@ int ovl_update_time(struct inode *inode, struct timespec64 *ts, int flags) > if (upperpath.dentry) { > touch_atime(&upperpath); > inode->i_atime = d_inode(upperpath.dentry)->i_atime; > + ovl_mark_inode_dirty(inode); > } > } > return 0; > diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h > index f8880aa2ba0e..eaf1d5b05d8e 100644 > --- a/fs/overlayfs/overlayfs.h > +++ b/fs/overlayfs/overlayfs.h > @@ -247,6 +247,7 @@ static inline bool ovl_open_flags_need_copy_up(int flags) > } > > /* util.c */ > +void ovl_mark_inode_dirty(struct inode *inode); > int ovl_want_write(struct dentry *dentry); > void ovl_drop_write(struct dentry *dentry); > struct dentry *ovl_workdir(struct dentry *dentry); > @@ -472,6 +473,9 @@ static inline void ovl_copyattr(struct inode *from, struct inode *to) > to->i_mtime = from->i_mtime; > to->i_ctime = from->i_ctime; > i_size_write(to, i_size_read(from)); > + > + if (ovl_inode_upper(to) && from->i_state & I_DIRTY_ALL) > + ovl_mark_inode_dirty(to); > } Okay, ovl_copyattr() certainly seems a good place to copy dirtyness as well. What I'm fearing is that it does not cover all the places where underlying inode can be dirtied. This really needs an audit of all filesystem modifying operations. > > static inline void ovl_copyflags(struct inode *from, struct inode *to) > diff --git a/fs/overlayfs/util.c b/fs/overlayfs/util.c > index 23f475627d07..a6f59df744ae 100644 > --- a/fs/overlayfs/util.c > +++ b/fs/overlayfs/util.c > @@ -950,3 +950,17 @@ char *ovl_get_redirect_xattr(struct ovl_fs *ofs, struct dentry *dentry, > kfree(buf); > return ERR_PTR(res); > } > + > +/* > + * We intentionally add I_DIRTY_SYNC flag regardless dirty flag > + * of upper inode so that we have chance to invoke ->write_inode > + * to re-dirty overlayfs' inode during writeback process. > + */ > +void ovl_mark_inode_dirty(struct inode *inode) > +{ > + struct inode *upper = ovl_inode_upper(inode); > + unsigned long iflag = I_DIRTY_SYNC; > + > + iflag |= upper->i_state & I_DIRTY_ALL; > + __mark_inode_dirty(inode, iflag); > +} > -- > 2.26.2 > >