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=-12.9 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,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 0CA85C433E2 for ; Tue, 8 Sep 2020 07:49:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CD32521D46 for ; Tue, 8 Sep 2020 07:49:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729342AbgIHHty (ORCPT ); Tue, 8 Sep 2020 03:49:54 -0400 Received: from mail.cn.fujitsu.com ([183.91.158.132]:25220 "EHLO heian.cn.fujitsu.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1729319AbgIHHtt (ORCPT ); Tue, 8 Sep 2020 03:49:49 -0400 X-IronPort-AV: E=Sophos;i="5.76,404,1592841600"; d="scan'208";a="98998490" Received: from unknown (HELO cn.fujitsu.com) ([10.167.33.5]) by heian.cn.fujitsu.com with ESMTP; 08 Sep 2020 15:49:45 +0800 Received: from G08CNEXMBPEKD06.g08.fujitsu.local (unknown [10.167.33.206]) by cn.fujitsu.com (Postfix) with ESMTP id CFFD448990D9; Tue, 8 Sep 2020 15:49:42 +0800 (CST) Received: from [10.167.220.69] (10.167.220.69) by G08CNEXMBPEKD06.g08.fujitsu.local (10.167.33.206) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Tue, 8 Sep 2020 15:49:41 +0800 Message-ID: <5F573794.2040700@cn.fujitsu.com> Date: Tue, 8 Sep 2020 15:49:40 +0800 From: Xiao Yang User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.2; zh-CN; rv:1.9.2.18) Gecko/20110616 Thunderbird/3.1.11 MIME-Version: 1.0 To: Dave Chinner , CC: , Subject: Re: [PATCH v3] xfs: Add check for unsupported xflags References: <20200903035713.60962-1-yangx.jy@cn.fujitsu.com> <20200903074632.GD12131@dread.disaster.area> <5F5194F1.8010607@cn.fujitsu.com> <20200906230105.GO12131@dread.disaster.area> In-Reply-To: <20200906230105.GO12131@dread.disaster.area> Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit X-Originating-IP: [10.167.220.69] X-ClientProxiedBy: G08CNEXCHPEKD06.g08.fujitsu.local (10.167.33.205) To G08CNEXMBPEKD06.g08.fujitsu.local (10.167.33.206) X-yoursite-MailScanner-ID: CFFD448990D9.AE2BD X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: yangx.jy@cn.fujitsu.com Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org On 2020/9/7 7:01, Dave Chinner wrote: > On Fri, Sep 04, 2020 at 09:14:25AM +0800, Xiao Yang wrote: >> On 2020/9/3 15:46, Dave Chinner wrote: >>> On Thu, Sep 03, 2020 at 11:57:13AM +0800, Xiao Yang wrote: >>>> Current ioctl(FSSETXATTR) ignores unsupported xflags silently >>>> so it is not clear for user to know unsupported xflags. >>>> For example, use ioctl(FSSETXATTR) to set dax flag on kernel >>>> v4.4 which doesn't support dax flag: >>>> -------------------------------- >>>> # xfs_io -f -c "chattr +x" testfile;echo $? >>>> 0 >>>> # xfs_io -c "lsattr" testfile >>>> ----------------X testfile >>>> -------------------------------- >>>> >>>> Add check to return -EOPNOTSUPP as ext4/f2fs/btrfs does. >>>> >>>> Signed-off-by: Xiao Yang >>>> Reviewed-by: Darrick J. Wong >>>> --- >>>> fs/xfs/xfs_ioctl.c | 12 ++++++++++++ >>>> 1 file changed, 12 insertions(+) >>>> >>>> diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c >>>> index 6f22a66777cd..59f9a86f29f7 100644 >>>> --- a/fs/xfs/xfs_ioctl.c >>>> +++ b/fs/xfs/xfs_ioctl.c >>>> @@ -1425,6 +1425,14 @@ xfs_ioctl_setattr_check_projid( >>>> return 0; >>>> } >>>> >>>> +#define XFS_SUPPORTED_FS_XFLAGS \ >>>> + (FS_XFLAG_REALTIME | FS_XFLAG_PREALLOC | FS_XFLAG_IMMUTABLE | \ >>>> + FS_XFLAG_APPEND | FS_XFLAG_SYNC | FS_XFLAG_NOATIME | FS_XFLAG_NODUMP | \ >>>> + FS_XFLAG_RTINHERIT | FS_XFLAG_PROJINHERIT | FS_XFLAG_NOSYMLINKS | \ >>>> + FS_XFLAG_EXTSIZE | FS_XFLAG_EXTSZINHERIT | FS_XFLAG_NODEFRAG | \ >>>> + FS_XFLAG_FILESTREAM | FS_XFLAG_DAX | FS_XFLAG_COWEXTSIZE | \ >>>> + FS_XFLAG_HASATTR) >>>> + >>>> STATIC int >>>> xfs_ioctl_setattr( >>>> xfs_inode_t *ip, >>>> @@ -1439,6 +1447,10 @@ xfs_ioctl_setattr( >>>> >>>> trace_xfs_ioctl_setattr(ip); >>>> >>>> + /* Check if fsx_xflags has unsupported xflags */ >>>> + if (fa->fsx_xflags& ~XFS_SUPPORTED_FS_XFLAGS) >>>> + return -EOPNOTSUPP; >>> I don't think we can do this as it may break existing applications >>> that have been working on XFS for many, many years that don't >>> correctly initialise fsx_xflags.... >> Hi Dave, >> >> It seems that the only way is to keep the current behavior. :-( > Yes, unfortunately that is the case, but it does follow precedence > set by other syscalls with unchecked flags such as open() - they > mask off unknown flags so they don't do anything, but they do not > return an error if any unknown flag is set. > >> By the way, _require_xfs_io_command "chattr" in xfstests cannot check XFS's >> unsupported xflags directly because of the behavior, so we may need to check >> them by extra xfs_io -c "lsattr". > *nod* Hi Darrick, Dave I had another confusion when trying to add extra xfs_io -c "lsattr" in xfstests: -------------------------------------------------- # xfs_io -f -c "chattr +tPn" file # xfs_io -f -c "lsattr" file ----------------X file # xfs_io -f -c "chattr +E" file xfs_io: cannot set flags on file: Invalid argument -------------------------------------------------- These four flags are invalid for a regular file , but kernel maskes off three flags and returns EINVAL for 'E' flag. kernel can mask off all four flags for a regular file, so is it necessary for 'E' flag to return EINVAL? fs/xfs/xfs_ioctl.c: ------------------------------------------------- 1160 if (S_ISDIR(VFS_I(ip)->i_mode)) { 1161 if (xflags & FS_XFLAG_RTINHERIT) 1162 di_flags |= XFS_DIFLAG_RTINHERIT; 1163 if (xflags & FS_XFLAG_NOSYMLINKS) 1164 di_flags |= XFS_DIFLAG_NOSYMLINKS; 1165 if (xflags & FS_XFLAG_EXTSZINHERIT) 1166 di_flags |= XFS_DIFLAG_EXTSZINHERIT; 1167 if (xflags & FS_XFLAG_PROJINHERIT) 1168 di_flags |= XFS_DIFLAG_PROJINHERIT; ------------------------------------------------- fs/inode.c: ------------------------------------------------- 2356 if ((fa->fsx_xflags & FS_XFLAG_EXTSZINHERIT) && 2357 !S_ISDIR(inode->i_mode)) 2358 return -EINVAL; ------------------------------------------------- I think the behavior of chattr command seems inconsistent/messy. Best Regards, Xiao Yang > Cheers, > > Dave.