Re: [PATCH V3 07/20] nvdimm/region_label: Add region label delete support

[Neeraj Kumar]

On 22/09/25 02:37PM, Dave Jiang wrote:
> > +int nd_pmem_region_label_delete(struct nd_region *nd_region)
> > +{
> > +	struct nd_interleave_set *nd_set = nd_region->nd_set;
> > +	struct nd_label_ent *label_ent;
> > +	int ns_region_cnt = 0;
> > +	int i, rc;
> > +
> > +	for (i = 0; i < nd_region->ndr_mappings; i++) {
> > +		struct nd_mapping *nd_mapping = &nd_region->mapping[i];
> > +		struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
> > +
> > +		/* Find non cxl format supported ndr_mappings */
> > +		if (!ndd->cxl) {
> > +			dev_info(&nd_region->dev, "Unsupported region label\n");
> > +			return -EINVAL;
> > +		}
> > +
> > +		/* Find if any NS label using this region */
> > +		guard(mutex)(&nd_mapping->lock);
> > +		list_for_each_entry(label_ent, &nd_mapping->labels, list) {
> > +			if (!label_ent->label)
> > +				continue;
> > +
> > +			/*
> > +			 * Check if any available NS labels has same
> > +			 * region_uuid in LSA
> > +			 */
> > +			if (nsl_region_uuid_equal(label_ent->label,
> > +						  &nd_set->uuid))
> > +				ns_region_cnt++;
>
> Why not just return -EBUSY here immediately? It seems the code returns -EBUSY as long as there's 1 or more below.
>
> > +		}
> > +	}
> > +
> > +	if (ns_region_cnt) {
> > +		dev_dbg(&nd_region->dev, "Region/Namespace label in use\n");
> > +		return -EBUSY;
> > +	}
> > +
> > +	for (i = 0; i < nd_region->ndr_mappings; i++) {
> > +		struct nd_mapping *nd_mapping = &nd_region->mapping[i];
> > +
> > +		rc = del_labels(nd_mapping, &nd_set->uuid, RG_LABEL_TYPE);
> > +		if (rc)
> > +			return rc;
> > +	}
>
> Can this be folded into the for loop above or does it a full pass to check before starting the label deletion process?
>
> DJ

Yes, if we use "return -EBUSY" in first loop itself then we can call del_labels()
I will fix this in next patch-set

Regards,
Neeraj