Re: [RFC PATCH 06/20] nvdimm/region_label: Add region label deletion routine

[Neeraj Kumar]

On 23/06/25 10:09AM, Jonathan Cameron wrote:
> On Tue, 17 Jun 2025 18:09:30 +0530
> Neeraj Kumar <s.neeraj@xxxxxxxxxxx> wrote:
>
> > Added cxl v2.1 format region label deletion routine. This function is
> > used to delete region label from LSA
> >
> > Signed-off-by: Neeraj Kumar <s.neeraj@xxxxxxxxxxx>
> > ---
> >  drivers/nvdimm/label.c          | 75 ++++++++++++++++++++++++++++++---
> >  drivers/nvdimm/label.h          |  6 +++
> >  drivers/nvdimm/namespace_devs.c | 12 ++++++
> >  drivers/nvdimm/nd.h             |  9 ++++
> >  include/linux/libnvdimm.h       |  1 +
> >  5 files changed, 98 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
> > index 7f33d14ce0ef..9381c50086fc 100644
> > --- a/drivers/nvdimm/label.c
> > +++ b/drivers/nvdimm/label.c
> > @@ -1034,7 +1034,8 @@ static int init_labels(struct nd_mapping *nd_mapping, int num_labels)
> >  	return max(num_labels, old_num_labels);
> >  }
> >
> > -static int del_labels(struct nd_mapping *nd_mapping, uuid_t *uuid)
> > +static int del_labels(struct nd_mapping *nd_mapping, uuid_t *uuid,
> > +		enum label_type ltype)
> >  {
> >  	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
> >  	struct nd_label_ent *label_ent, *e;
> > @@ -1058,8 +1059,18 @@ static int del_labels(struct nd_mapping *nd_mapping, uuid_t *uuid)
> >  		if (!nd_label)
> >  			continue;
> >  		active++;
> > -		if (!nsl_uuid_equal(ndd, &nd_label->ns_label, uuid))
> > -			continue;
> > +
> > +		if (ltype == NS_LABEL_TYPE) {
>
> Perhaps a switch is more appropriate here.

Sure will update it in V1

> > +			if (!nsl_uuid_equal(ndd, &nd_label->ns_label, uuid))
> > +				continue;
> > +		} else if (ltype == RG_LABEL_TYPE) {
> > +			if (!nsl_uuid_equal(ndd, &nd_label->ns_label, uuid))
> > +				continue;
> > +		} else {
> > +			dev_err(ndd->dev, "Invalid label type\n");
> > +			return 0;
> > +		}
> > +
> >  		active--;
> >  		slot = to_slot(ndd, nd_label);
> >  		nd_label_free_slot(ndd, slot);
>
> > @@ -1259,6 +1271,59 @@ int nd_pmem_region_label_update(struct nd_region *nd_region)
> >  	return 0;
> >  }
> >
> > +int nd_pmem_region_label_delete(struct nd_region *nd_region)
> > +{
> > +	int i, rc;
> > +	struct nd_interleave_set *nd_set = nd_region->nd_set;
> > +	struct nd_label_ent *label_ent;
> > +	bool is_non_rgl = false;
> > +	int ns_region_cnt = 0;
> > +
> > +	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)
> > +			is_non_rgl = true;
> > +
> > +		/* Find if any NS label using this region */
> > +		mutex_lock(&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
>
> Looks like wrong style for multiline comments in this file.
>
> 			/*
> 			 * Check ...

Thanks, Will update it accordingly in V1

> > +			 * region_uuid in LSA
> > +			 */
> > +			if (nsl_region_uuid_equal(&label_ent->label->ns_label,
> > +						  &nd_set->uuid))
> > +				ns_region_cnt++;
> > +		}
> > +		mutex_unlock(&nd_mapping->lock);
> > +	}
> > +
> > +	if (is_non_rgl) {
> > +		dev_dbg(&nd_region->dev, "Region label deletion unsupported\n");
> > +		return -EINVAL;
>
> Why not bail out where you originally detect that above?

Thanks, Will fix it in V1

> > +	}
> > +
> > +	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;
> > +	}
> > +
> > +	return 0;
> > +}