From: Theodore Ts'o Subject: Re: [PATCH 1/4] fs: split update_time() into update_time() and write_time() Date: Mon, 24 Nov 2014 12:22:16 -0500 Message-ID: <20141124172216.GC31339@thunk.org> References: <1416599964-21892-1-git-send-email-tytso@mit.edu> <1416599964-21892-2-git-send-email-tytso@mit.edu> <1416600528.24312.10@mail.thefacebook.com> <20141121214245.GG7112@thunk.org> <20141124163830.GA26471@twin.jikos.cz> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii To: dsterba@suse.cz, Chris Mason , linux-fsdevel@vger.kernel.org, Ext4 Developers List , xfs@oss.sgi.com, linux-btrfs@vger.kernel.org Return-path: Received: from imap.thunk.org ([74.207.234.97]:47980 "EHLO imap.thunk.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751680AbaKXRWT (ORCPT ); Mon, 24 Nov 2014 12:22:19 -0500 Content-Disposition: inline In-Reply-To: <20141124163830.GA26471@twin.jikos.cz> Sender: linux-ext4-owner@vger.kernel.org List-ID: On Mon, Nov 24, 2014 at 05:38:30PM +0100, David Sterba wrote: > > It is necessary and the whole .update_time callback was added > intentionally, see commits > > c3b2da314834499f34cba94f7053e55f6d6f92d8 > fs: introduce inode operation ->update_time > > e41f941a23115e84a8550b3d901a13a14b2edc2f > Btrfs: move over to use ->update_time Being able to signal an error if the time update fails is still possible even if we drop update_time(), because the new write_time() function will return an error. > 2bc5565286121d2a77ccd728eb3484dff2035b58 > Btrfs: don't update atime on RO subvolumes Yes, but this doesn't answer my question about other places where the VFS is only checking MS_RDONLY and MNT_READONLY besides just update_atime(). Maybe we should be exposing an "is_readonly(inode)" inode operations function to address this? - Ted