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=-8.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 03679C47404 for ; Wed, 9 Oct 2019 12:51:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D6A8D20B7C for ; Wed, 9 Oct 2019 12:51:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729686AbfJIMvQ (ORCPT ); Wed, 9 Oct 2019 08:51:16 -0400 Received: from mx1.redhat.com ([209.132.183.28]:50064 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728200AbfJIMvQ (ORCPT ); Wed, 9 Oct 2019 08:51:16 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 60429883856; Wed, 9 Oct 2019 12:51:15 +0000 (UTC) Received: from bfoster (dhcp-41-2.bos.redhat.com [10.18.41.2]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 976395D9E2; Wed, 9 Oct 2019 12:51:14 +0000 (UTC) Date: Wed, 9 Oct 2019 08:51:12 -0400 From: Brian Foster To: Ian Kent Cc: linux-xfs , Eric Sandeen , David Howells , Dave Chinner , Al Viro Subject: Re: [PATCH v5 13/17] xfs: mount api - add xfs_reconfigure() Message-ID: <20191009125112.GA29646@bfoster> References: <157062043952.32346.977737248061083292.stgit@fedora-28> <157062067944.32346.8228418435930532076.stgit@fedora-28> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <157062067944.32346.8228418435930532076.stgit@fedora-28> User-Agent: Mutt/1.12.1 (2019-06-15) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.6.2 (mx1.redhat.com [10.5.110.69]); Wed, 09 Oct 2019 12:51:15 +0000 (UTC) Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On Wed, Oct 09, 2019 at 07:31:19PM +0800, Ian Kent wrote: > Add the fs_context_operations method .reconfigure that performs > remount validation as previously done by the super_operations > .remount_fs method. > > Signed-off-by: Ian Kent > --- Reviewed-by: Brian Foster > fs/xfs/xfs_super.c | 62 ++++++++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 62 insertions(+) > > diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c > index 7e634706626b..230b0e2a184c 100644 > --- a/fs/xfs/xfs_super.c > +++ b/fs/xfs/xfs_super.c > @@ -1544,6 +1544,67 @@ xfs_fs_remount( > return 0; > } > > +/* > + * Logically we would return an error here to prevent users > + * from believing they might have changed mount options using > + * remount which can't be changed. > + * > + * But unfortunately mount(8) adds all options from mtab and > + * fstab to the mount arguments in some cases so we can't > + * blindly reject options, but have to check for each specified > + * option if it actually differs from the currently set option > + * and only reject it if that's the case. > + * > + * Until that is implemented we return success for every remount > + * request, and silently ignore all options that we can't actually > + * change. > + */ > +STATIC int > +xfs_reconfigure( > + struct fs_context *fc) > +{ > + struct xfs_fs_context *ctx = fc->fs_private; > + struct xfs_mount *mp = XFS_M(fc->root->d_sb); > + struct xfs_mount *new_mp = fc->s_fs_info; > + xfs_sb_t *sbp = &mp->m_sb; > + int flags = fc->sb_flags; > + int error; > + > + error = xfs_validate_params(new_mp, ctx, false); > + if (error) > + return error; > + > + /* inode32 -> inode64 */ > + if ((mp->m_flags & XFS_MOUNT_SMALL_INUMS) && > + !(new_mp->m_flags & XFS_MOUNT_SMALL_INUMS)) { > + mp->m_flags &= ~XFS_MOUNT_SMALL_INUMS; > + mp->m_maxagi = xfs_set_inode_alloc(mp, sbp->sb_agcount); > + } > + > + /* inode64 -> inode32 */ > + if (!(mp->m_flags & XFS_MOUNT_SMALL_INUMS) && > + (new_mp->m_flags & XFS_MOUNT_SMALL_INUMS)) { > + mp->m_flags |= XFS_MOUNT_SMALL_INUMS; > + mp->m_maxagi = xfs_set_inode_alloc(mp, sbp->sb_agcount); > + } > + > + /* ro -> rw */ > + if ((mp->m_flags & XFS_MOUNT_RDONLY) && !(flags & SB_RDONLY)) { > + error = xfs_remount_rw(mp); > + if (error) > + return error; > + } > + > + /* rw -> ro */ > + if (!(mp->m_flags & XFS_MOUNT_RDONLY) && (flags & SB_RDONLY)) { > + error = xfs_remount_ro(mp); > + if (error) > + return error; > + } > + > + return 0; > +} > + > /* > * Second stage of a freeze. The data is already frozen so we only > * need to take care of the metadata. Once that's done sync the superblock > @@ -2069,6 +2130,7 @@ static const struct super_operations xfs_super_operations = { > static const struct fs_context_operations xfs_context_ops = { > .parse_param = xfs_parse_param, > .get_tree = xfs_get_tree, > + .reconfigure = xfs_reconfigure, > }; > > static struct file_system_type xfs_fs_type = { >