Re: [PATCH V2 10/20] nvdimm/region_label: Preserve cxl region information from region label

[Neeraj Kumar]

On 13/08/25 04:11PM, Jonathan Cameron wrote:
> On Wed, 30 Jul 2025 17:41:59 +0530
> Neeraj Kumar <s.neeraj@xxxxxxxxxxx> wrote:
>
> > Preserve region information from region label during nvdimm_probe. This
> > preserved region information is used for creating cxl region to achieve
> > region persistency across reboot.
> >
> > Signed-off-by: Neeraj Kumar <s.neeraj@xxxxxxxxxxx>
>
> See below.
>
> > diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
> > index 064a945dcdd1..bcac05371f87 100644
> > --- a/drivers/nvdimm/label.c
> > +++ b/drivers/nvdimm/label.c
> > @@ -473,6 +473,47 @@ int nd_label_reserve_dpa(struct nvdimm_drvdata *ndd)
> >  	return 0;
> >  }
> >
> > +int nvdimm_cxl_region_preserve(struct nvdimm_drvdata *ndd)
> > +{
> > +	struct nvdimm *nvdimm = to_nvdimm(ndd->dev);
> > +	struct cxl_pmem_region_params *params = &nvdimm->cxl_region_params;
> > +	struct nd_namespace_index *nsindex;
> > +	unsigned long *free;
> > +	u32 nslot, slot;
> > +
> > +	if (!preamble_current(ndd, &nsindex, &free, &nslot))
> > +		return 0; /* no label, nothing to preserve */
> > +
> > +	for_each_clear_bit_le(slot, free, nslot) {
> > +		struct nd_lsa_label *nd_label;
> > +		struct cxl_region_label *rg_label;
> > +		uuid_t rg_type, region_type;
> > +
> > +		nd_label = to_label(ndd, slot);
> > +		rg_label = &nd_label->rg_label;
> > +		uuid_parse(CXL_REGION_UUID, &region_type);
> > +		import_uuid(&rg_type, nd_label->rg_label.type);
> > +
> > +		/* REVISIT: Currently preserving only one region */
>
> In practice, is this a significant issue or not?  I.e. should we not
> merge this series until this has been revisited?

As currently we have support of Interleave way == 1, thats why this
REVISIST. I will remove this, as its not significant issue for merging this series


Regards,
Neeraj