On Thu, Jan 07, 2021 at 03:36:34PM -0600, Eric Sandeen wrote: > Today, xfs_reflink_remap_prep() will reject inodes which are in the CPU > direct access state, i.e. IS_DAX() is true. However, it is possible to > have inodes with the XFS_DIFLAG2_DAX set, but which are not activated as > dax, due to the flag being set after the inode was loaded. > > To avoid confusion and make the lack of dax+reflink crystal clear for the > user, reject reflink requests for both IS_DAX and XFS_DIFLAG2_DAX inodes > unless DAX mode is impossible due to mounting with -o dax=never. I thought we were allowing arbitrary combinations of DAX & REFLINK inode flags now, since we're now officially ok with "you set the inode flag but you don't get cpu direct access because $reasons"? --D > Signed-off-by: Eric Sandeen <sandeen@xxxxxxxxxx> > --- > V2: Allow reflinking dax-flagged inodes in "mount -o dax=never" mode > > diff --git a/fs/xfs/xfs_reflink.c b/fs/xfs/xfs_reflink.c > index 6fa05fb78189..e238a5b7b722 100644 > --- a/fs/xfs/xfs_reflink.c > +++ b/fs/xfs/xfs_reflink.c > @@ -1308,6 +1308,15 @@ xfs_reflink_remap_prep( > if (IS_DAX(inode_in) || IS_DAX(inode_out)) > goto out_unlock; > > + /* > + * Until we have dax+reflink, don't allow reflinking dax-flagged > + * inodes unless we are in dax=never mode. > + */ > + if (!(mp->m_flags & XFS_MOUNT_DAX_NEVER) && > + (src->i_d.di_flags2 & XFS_DIFLAG2_DAX || > + dest->i_d.di_flags2 & XFS_DIFLAG2_DAX)) > + goto out_unlock; > + > ret = generic_remap_file_range_prep(file_in, pos_in, file_out, pos_out, > len, remap_flags); > if (ret || *len == 0) >
