On Thu, Aug 26, 2021 at 01:16:22PM -0500, Eric Sandeen wrote:
>
> On 8/26/21 1:09 PM, Darrick J. Wong wrote:
> > On Thu, Aug 26, 2021 at 12:30:12PM -0500, Bill O'Donnell wrote:
>
> > > @@ -1584,7 +1586,7 @@ xfs_fs_fill_super(
> > > if (xfs_has_crc(mp))
> > > sb->s_flags |= SB_I_VERSION;
> > > - if (xfs_has_dax_always(mp)) {
> > > + if (xfs_has_dax_always(mp) || xfs_has_dax_inode(mp)) {
> >
> > Er... can't this be done without burning another feature bit by:
> >
> > if (xfs_has_dax_always(mp) || (!xfs_has_dax_always(mp) &&
> > !xfs_has_dax_never(mp))) {
> > ...
> > xfs_warn(mp, "DAX IS EXPERIMENTAL");
> > }
>
> changing this conditional in this way will also fail dax=inode mounts on
> reflink-capable (i.e. default) filesystems, no?
Correct. My original patch tests fine, and still handles the reflink and dax
incompatibility. The new suggested logic is problematic.
-Bill
>
> - if (xfs_has_dax_always(mp)) {
> + if (xfs_has_dax_always(mp) || $NEW_DAX_INODE_TEST) {
>
> ...
> if (xfs_has_reflink(mp)) {
> xfs_alert(mp,
> "DAX and reflink cannot be used together!");
> error = -EINVAL;
> goto out_filestream_unmount;
> }
> }
>
> -Eric
>
