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 Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 918F5C001B0 for ; Wed, 9 Aug 2023 22:07:48 +0000 (UTC) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=jLUEcluJ; dkim-atps=neutral Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4RLkh26hHMz3cHP for ; Thu, 10 Aug 2023 08:07:46 +1000 (AEST) Authentication-Results: lists.ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=jLUEcluJ; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=kernel.org (client-ip=139.178.84.217; helo=dfw.source.kernel.org; envelope-from=jlayton@kernel.org; receiver=lists.ozlabs.org) Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4RLkgw2sn8z2yGg for ; Thu, 10 Aug 2023 08:07:40 +1000 (AEST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id C164F6142A; Wed, 9 Aug 2023 22:07:37 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B8A1FC433C8; Wed, 9 Aug 2023 22:07:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1691618857; bh=Sbngo3UIZo2TJfFo7ktsW7U9FXdWGIk5Lt7H9K5XFM8=; h=Subject:From:To:Cc:Date:In-Reply-To:References:From; b=jLUEcluJ8QWu44nwg8FvEto5mxdSD6jhT4hkYGZFSvOuTab/uQF0xUgz8zLDtJscq f+HBUBgdFJj3+Y2ejcBWfM2DahqOuHFBxu+LY+Hv0Ofoq0ohoPPQ6mfudIqZwl+oWN pLNza58hUz5pcfryyZpEKO+0VcHneBut5CYMVVo+IlIVXRYDByI99w4/3LNaQTR8ZH 5Tcm+fOwhAMw+LBYRd9XcCm1AD2BTsoO11JuCHNeGAZ3X/S7nnQe6dSMtz75w2+y5t 1AyLcsRC7pto0A+XhqMGGaQoyj7sZyZ0q03rK2TphlgLtVEfD926pjyggGNcgTjePk OQw0IGY/USDEA== Message-ID: Subject: Re: [PATCH v7 05/13] fat: make fat_update_time get its own timestamp From: Jeff Layton To: OGAWA Hirofumi , Frank Sorenson Date: Wed, 09 Aug 2023 18:07:29 -0400 In-Reply-To: <87a5v06kij.fsf@mail.parknet.co.jp> 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> <87h6p86p9z.fsf@mail.parknet.co.jp> <87a5v06kij.fsf@mail.parknet.co.jp> Content-Type: text/plain; charset="ISO-8859-15" Content-Transfer-Encoding: quoted-printable User-Agent: Evolution 3.48.4 (3.48.4-1.fc38) MIME-Version: 1.0 X-BeenThere: linux-erofs@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Development of Linux EROFS file system List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Latchesar Ionkov , Martin Brandenburg , Konstantin Komarov , Jan Kara , "Darrick J. Wong" , Dominique Martinet , Christian Schoenebeck , ecryptfs@vger.kernel.org, Yue Hu , David Howells , Chris Mason , Andreas Dilger , Hans de Goede , Marc Dionne , linux-xfs@vger.kernel.org, linux-afs@lists.infradead.org, linux-mtd@lists.infradead.org, Mike Marshall , Paulo Alcantara , linux-cifs@vger.kernel.org, Eric Van Hensbergen , Andreas Gruenbacher , Miklos Szeredi , Richard Weinberger , Mark Fasheh , linux-unionfs@vger.kernel.org, Hugh Dickins , Benjamin Coddington , Tyler Hicks , cluster-devel@redhat.com, coda@cs.cmu.edu, linux-mm@kvack.org, Ilya Dryomov , Iurii Zaikin , Namjae Jeon , Trond Myklebust , codalist@telemann.coda.cs.cmu.edu, Shyam Prasad N , Amir Goldstein , Kees Cook , ocfs2-devel@lists.linux.dev, Josef Bacik , Tom Talpey , Tejun Heo , Alexander Viro , Ronnie Sahlberg , David Sterba , Jaegeuk Kim , ceph-devel@vger.kernel.org, Xiubo Li , Jan Harkes , Christian Brauner , linux-ext4@vger.kernel.org, Theodore Ts'o , Joseph Qi , Greg Kroah-Hartman , v9fs@lists.linux.dev, ntfs3@lists.linux.dev, samba-technical@lists.samba.org, linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, Steve French , Sergey Senozhatsky , Luis Chamberlain , devel@lists.orangefs.org, Anna Schumaker , Jan Kara , Bob Peterson , linux-fsdevel@vger.kernel.org, Andrew Morton , Sungjong Seo , linux-erofs@lists.ozlabs.org, linux-nfs@vger.kernel.org, linux-btrfs@vger.kernel.org, Joel Becker Errors-To: linux-erofs-bounces+linux-erofs=archiver.kernel.org@lists.ozlabs.org Sender: "Linux-erofs" On Thu, 2023-08-10 at 05:14 +0900, OGAWA Hirofumi wrote: > Jeff Layton writes: >=20 > > When you say it "doesn't work the same", what do you mean, specifically= ? > > I had to make some allowances for the fact that FAT is substantially > > different in its timestamp handling, and I tried to preserve existing > > behavior as best I could. >=20 > Ah, ok. I was misreading some. >=20 > inode_update_timestamps() checks IS_I_VERSION() now, not S_VERSION. So, > if adding the check of IS_I_VERSION() and (S_MTIME|S_CTIME|S_VERSION) to > FAT? >=20 > With it, IS_I_VERSION() would be false on FAT, and I'm fine. >=20 > I.e. something like >=20 > if ((flags & (S_VERSION|S_CTIME|S_MTIME)) && IS_I_VERSION(inode) > && inode_maybe_inc_iversion(inode, false)) > dirty_flags |=3D I_DIRTY_SYNC; >=20 > Thanks. 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: --------------------8<------------------ int fat_update_time(struct inode *inode, int flags)=20 {=20 int dirty_flags =3D 0; if (inode->i_ino =3D=3D MSDOS_ROOT_INO)=20 return 0; fat_truncate_time(inode, NULL, flags); if (inode->i_sb->s_flags & SB_LAZYTIME) dirty_flags |=3D I_DIRTY_TIME; else dirty_flags |=3D I_DIRTY_SYNC; __mark_inode_dirty(inode, dirty_flags); return 0; }=20 --------------------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! --=20 Jeff Layton