Re: [RFE] xfs_growfs: option to clamp growth to an AG boundary

["Darrick J. Wong" <djwong@kernel.org>]

On Tue, Feb 24, 2026 at 07:01:11AM -0800, Christoph Hellwig wrote:
> On Mon, Feb 23, 2026 at 03:08:40PM -0800, Darrick J. Wong wrote:
> > On Tue, Feb 24, 2026 at 12:29:49AM +0500, Марк Коренберг wrote:
> > > ```
> > > cp: failed to clone
> > > '/run/ideco-overlay-dir/ideco-trash-o4ut52ue/upperdir/var/lib/clickhouse/store/e2b/e2bdef56-6be8-40bf-8fab-d8fb2e9fdd94/90-20250905_11925_11925_0/primary.cidx'
> > > from '/run/ideco-overlay-dir/storage/ideco-ngfw-19-7-19/upperdir/var/lib/clickhouse/store/e2b/e2bdef56-6be8-40bf-8fab-d8fb2e9fdd94/90-20250905_11925_11925_0/primary.cidx':
> > > No space left on device
> > 
> > Ah, that.  coreutils seems to think that FICLONE returning ENOSPC is a
> > fatal error.  I wonder if we need to amend the ficlone manpage to state
> > that ENOSPC can happen if there's not enough space in an AG to clone and
> > that the caller might try a regular copy; or just change xfs to return a
> > different errno?
> 
> I think the problem is that we report ENOSPC for this.  The historic
> error code coming from the old btrfs days is EINVAL for "can't support
> this for random unlisted reason", which btrfs does for example for
> inline extents.  We really should turn ENOSPC into that.

Yeah, I'll give that a spin.

--D