Received-SPF: pass (google.com: domain of linux-nfs-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
To:     Jeff Layton <jlayton@kernel.org>
Cc:     Frank Sorenson <sorenson@redhat.com>, Jan Kara <jack@suse.cz>,
        Alexander Viro <viro@zeniv.linux.org.uk>,
        Christian Brauner <brauner@kernel.org>,
        Eric Van Hensbergen <ericvh@kernel.org>,
        Latchesar Ionkov <lucho@ionkov.net>,
        Dominique Martinet <asmadeus@codewreck.org>,
        Christian Schoenebeck <linux_oss@crudebyte.com>,
        David Howells <dhowells@redhat.com>,
        Marc Dionne <marc.dionne@auristor.com>,
        Chris Mason <clm@fb.com>, Josef Bacik <josef@toxicpanda.com>,
        David Sterba <dsterba@suse.com>, Xiubo Li <xiubli@redhat.com>,
        Ilya Dryomov <idryomov@gmail.com>,
        Jan Harkes <jaharkes@cs.cmu.edu>, coda@cs.cmu.edu,
        Tyler Hicks <code@tyhicks.com>, Gao Xiang <xiang@kernel.org>,
        Chao Yu <chao@kernel.org>,
        Yue Hu <huyue2@gl0jj8bn.sched.sma.tdnsstic1.cn>,
        Jeffle Xu <jefflexu@linux.alibaba.com>,
        Namjae Jeon <linkinjeon@kernel.org>,
        Sungjong Seo <sj1557.seo@samsung.com>,
        Jan Kara <jack@suse.com>, "Theodore Ts'o" <tytso@mit.edu>,
        Andreas Dilger <adilger.kernel@dilger.ca>,
        Jaegeuk Kim <jaegeuk@kernel.org>,
        Miklos Szeredi <miklos@szeredi.hu>,
        Bob Peterson <rpeterso@redhat.com>,
        Andreas Gruenbacher <agruenba@redhat.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Tejun Heo <tj@kernel.org>,
        Trond Myklebust <trond.myklebust@hammerspace.com>,
        Anna Schumaker <anna@kernel.org>,
        Konstantin Komarov <almaz.alexandrovich@paragon-software.com>,
        Mark Fasheh <mark@fasheh.com>,
        Joel Becker <jlbec@evilplan.org>,
        Joseph Qi <joseph.qi@linux.alibaba.com>,
        Mike Marshall <hubcap@omnibond.com>,
        Martin Brandenburg <martin@omnibond.com>,
        Luis Chamberlain <mcgrof@kernel.org>,
        Kees Cook <keescook@chromium.org>,
        Iurii Zaikin <yzaikin@google.com>,
        Steve French <sfrench@samba.org>,
        Paulo Alcantara <pc@manguebit.com>,
        Ronnie Sahlberg <ronniesahlberg@gmail.com>,
        Shyam Prasad N <sprasad@microsoft.com>,
        Tom Talpey <tom@talpey.com>,
        Sergey Senozhatsky <senozhatsky@chromium.org>,
        Richard Weinberger <richard@nod.at>,
        Hans de Goede <hdegoede@redhat.com>,
        Hugh Dickins <hughd@google.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Amir Goldstein <amir73il@gmail.com>,
        "Darrick J. Wong" <djwong@kernel.org>,
        Benjamin Coddington <bcodding@redhat.com>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        v9fs@lists.linux.dev, linux-afs@lists.infradead.org,
        linux-btrfs@vger.kernel.org, ceph-devel@vger.kernel.org,
        codalist@telemann.coda.cs.cmu.edu, ecryptfs@vger.kernel.org,
        linux-erofs@lists.ozlabs.org, linux-ext4@vger.kernel.org,
        linux-f2fs-devel@lists.sourceforge.net, cluster-devel@redhat.com,
        linux-nfs@vger.kernel.org, ntfs3@lists.linux.dev,
        ocfs2-devel@lists.linux.dev, devel@lists.orangefs.org,
        linux-cifs@vger.kernel.org, samba-technical@lists.samba.org,
        linux-mtd@lists.infradead.org, linux-mm@kvack.org,
        linux-unionfs@vger.kernel.org, linux-xfs@vger.kernel.org
Subject: Re: [PATCH v7 05/13] fat: make fat_update_time get its own timestamp
In-Reply-To: <e4cee2590f5cb9a13a8d4445e550e155d551670d.camel@kernel.org> (Jeff
        Layton's message of "Wed, 09 Aug 2023 18:07:29 -0400")
References: <20230807-mgctime-v7-0-d1dec143a704@kernel.org>
        <20230807-mgctime-v7-5-d1dec143a704@kernel.org>
        <87msz08vc7.fsf@mail.parknet.co.jp>
        <52bead1d6a33fec89944b96e2ec20d1ea8747a9a.camel@kernel.org>
        <878rak8hia.fsf@mail.parknet.co.jp>
        <20230809150041.452w7gucjmvjnvbg@quack3>
        <87v8do6y8q.fsf@mail.parknet.co.jp>
        <2cb998ff14ace352a9dd553e82cfa0aa92ec09ce.camel@kernel.org>
        <87leek6rh1.fsf@mail.parknet.co.jp>
        <ccffe6ca3397c8374352b002fe01d55b09d84ef4.camel@kernel.org>
        <87h6p86p9z.fsf@mail.parknet.co.jp>
        <edf8e8ca3b38e56f30e0d24ac7293f848ffee371.camel@kernel.org>
        <87a5v06kij.fsf@mail.parknet.co.jp>
        <e4cee2590f5cb9a13a8d4445e550e155d551670d.camel@kernel.org>
Date:   Thu, 10 Aug 2023 07:37:52 +0900
Message-ID: <87zg2z3kqn.fsf@mail.parknet.co.jp>
User-Agent: Gnus/5.13 (Gnus v5.13)
MIME-Version: 1.0
Content-Type: text/plain
Precedence: bulk

Jeff Layton <jlayton@kernel.org> writes:

> If you do that then the i_version counter would never be incremented.
> But...I think I see what you're getting at.
>
> Most filesystems that support the i_version counter have an on-disk
> field for it. FAT obviously has no such thing. I suspect the i_version
> bits in fat_update_time were added by mistake. FAT doesn't set
> SB_I_VERSION so there's no need to do anything to the i_version field at
> all.
>
> Also, given that the mtime and ctime are always kept in sync on FAT,
> we're probably fine to have it look something like this:

Yes.

IIRC, when I wrote, I decided to make it keep similar with generic
function, instead of heavily customize for FAT (for maintenance
reason). It is why. There would be other places with same reason.

E.g. LAZYTIME check is same reason too. (current FAT doesn't support it)

So I personally I would prefer to leave it. But if you want to remove
it, it would be ok too.

Thanks.

> --------------------8<------------------
> int fat_update_time(struct inode *inode, int flags) 
> { 
>         int dirty_flags = 0;
>
>         if (inode->i_ino == MSDOS_ROOT_INO) 
>                 return 0;
>
>         fat_truncate_time(inode, NULL, flags);
>         if (inode->i_sb->s_flags & SB_LAZYTIME)
>                 dirty_flags |= I_DIRTY_TIME;
>         else
>                 dirty_flags |= I_DIRTY_SYNC;
>
>         __mark_inode_dirty(inode, dirty_flags);
>         return 0;
> } 
> --------------------8<------------------
>
> ...and we should probably do that in a separate patch in advance of the
> update_time rework, since it's really a different change.
>
> If you're in agreement, then I'll plan to respin the series with this
> fixed and resend.
>
> Thanks for being patient!
-- 
OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>