Re: [RFC PATCH v3 1/3] common/xfs: add a _require_xfs_shrink helper

[Gao Xiang <hsiangkao@redhat.com>]

On Mon, Mar 29, 2021 at 12:18:25AM +0800, Eryu Guan wrote:
> On Mon, Mar 15, 2021 at 07:19:24PM +0800, Gao Xiang wrote:
> > In order to detect whether the current kernel supports XFS shrinking.
> > 
> > Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
> > ---
> >  common/xfs | 11 +++++++++++
> >  1 file changed, 11 insertions(+)
> > 
> > diff --git a/common/xfs b/common/xfs
> > index 2156749d..ea3b6cab 100644
> > --- a/common/xfs
> > +++ b/common/xfs
> > @@ -432,6 +432,17 @@ _supports_xfs_scrub()
> >  	return 0
> >  }
> >  
> > +_require_xfs_shrink()
> > +{
> > +	_require_scratch
> 
> _require_command "$XFS_GROWFS_PROG" xfs_growfs

will update.

> 
> > +
> > +	_scratch_mkfs_xfs > /dev/null
> > +	_scratch_mount
> > +	$XFS_GROWFS_PROG -D1 "$SCRATCH_MNT" 2>&1 | grep -q 'Invalid argument' || \
> > +		_notrun "kernel does not support shrinking"
> 
> Better to describe the behavior here to explain why EINVAL means kernel
> supports shrink.

hmmm.. I also don't think this check is correct now. Maybe try to shrink
one fs-block would be better. Will update later.

Thanks,
Gao Xiang

> 
> Thanks,
> Eryu
> 
> > +	_scratch_unmount
> > +}
> > +
> >  # run xfs_check and friends on a FS.
> >  _check_xfs_filesystem()
> >  {
> > -- 
> > 2.27.0
>