From: Dave Jiang Subject: [PATCH v3 3/3] xfs: reject removal of realtime flag when datadev doesn't support DAX Date: Thu, 08 Feb 2018 17:38:24 -0700 Message-ID: <151813670468.15926.3966047346830424677.stgit@djiang5-desk3.ch.intel.com> References: <151813659955.15926.8922476613392258086.stgit@djiang5-desk3.ch.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Cc: linux-nvdimm-hn68Rpc1hR1g9hUCZPvPmw@public.gmane.org, david-FqsqvQoI3Ljby3iVrkZq2A@public.gmane.org, linux-xfs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-ext4-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: darrick.wong-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org Return-path: In-Reply-To: <151813659955.15926.8922476613392258086.stgit-Cxk7aZI4ujnJARH06PadV2t3HXsI98Cx0E9HWUfgJXw@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linux-nvdimm-bounces-hn68Rpc1hR1g9hUCZPvPmw@public.gmane.org Sender: "Linux-nvdimm" List-Id: linux-ext4.vger.kernel.org In a situation where the rt_dev is DAX and data_dev is not DAX, if the user requests to remove the realtime flag via ioctl we can no longer support DAX for that file. Dynamic changing of S_DAX on the inode is not supported due to various complications in the existing implementation. Therefore until we address the dynamic S_DAX change issues, we must disallow realtime flag being removed. Signed-off-by: Dave Jiang --- fs/xfs/xfs_ioctl.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c index e440d789ed1b..cd5a5c61da39 100644 --- a/fs/xfs/xfs_ioctl.c +++ b/fs/xfs/xfs_ioctl.c @@ -1029,6 +1029,21 @@ xfs_ioctl_setattr_xflags( { struct xfs_mount *mp = ip->i_mount; uint64_t di_flags2; + struct inode *inode = VFS_I(ip); + struct super_block *sb = inode->i_sb; + + /* + * In the case that the inode is realtime, and we are trying to remove + * the realtime flag, and the rtdev supports DAX but the datadev does + * not support DAX, we can't allow the realtime flag to be removed + * since we do not support dynamic S_DAX flag removal yet. + */ + if ((XFS_IS_REALTIME_INODE(ip)) && + !(fa->fsx_xflags & FS_XFLAG_REALTIME) && + bdev_dax_supported(sb, mp->m_rtdev_targp->bt_bdev, + sb->s_blocksize) && + !bdev_dax_supported(sb, mp->m_ddev_targp->bt_bdev, sb->s_blocksize)) + return -ENOTSUPP; /* Can't change realtime flag if any extents are allocated. */ if ((ip->i_d.di_nextents || ip->i_delayed_blks) &&