Re: [PATCH V4 07/17] nvdimm/label: Add region label delete support

[Neeraj Kumar]

On 17/12/25 03:05PM, Jonathan Cameron wrote:

On Wed, 19 Nov 2025 13:22:45 +0530
Neeraj Kumar <s.nee...@samsung.com> wrote:

Create export routine nd_region_label_delete() used for deleting
region label from LSA. It will be used later from CXL subsystem

Signed-off-by: Neeraj Kumar <s.nee...@samsung.com>

A few minor things inline.

Reviewed-by: Jonathan Cameron <jonathan.came...@huawei.com>

---
 drivers/nvdimm/label.c          | 76 ++++++++++++++++++++++++++++++---
 drivers/nvdimm/label.h          |  1 +
 drivers/nvdimm/namespace_devs.c | 12 ++++++
 drivers/nvdimm/nd.h             |  6 +++
 include/linux/libnvdimm.h       |  1 +
 5 files changed, 90 insertions(+), 6 deletions(-)

diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
index e90e48672da3..da55ecd95e2f 100644
--- a/drivers/nvdimm/label.c
+++ b/drivers/nvdimm/label.c
@@ -1225,7 +1225,8 @@ 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;
@@ -1244,11 +1245,25 @@ static int del_labels(struct nd_mapping *nd_mapping, 
uuid_t *uuid)

        mutex_lock(&nd_mapping->lock);
        list_for_each_entry_safe(label_ent, e, &nd_mapping->labels, list) {
-               if (label_ent->label)
+               if ((ltype == NS_LABEL_TYPE && !label_ent->label) ||
+                   (ltype == RG_LABEL_TYPE && !label_ent->region_label))
                        continue;
                active++;
-               if (!nsl_uuid_equal(ndd, label_ent->label, uuid))
-                       continue;
+
+               switch (ltype) {
+               case NS_LABEL_TYPE:
+                       if (!nsl_uuid_equal(ndd, label_ent->label, uuid))
+                               continue;
+
+                       break;
+               case RG_LABEL_TYPE:
+                       if (!region_label_uuid_equal(label_ent->region_label,
+                           uuid))

Align after equal( or just go a bit long on this line to improve readability.

Fixed it in V5

+                               continue;
+
+                       break;
+               }
+

@@ -1381,6 +1399,52 @@ int nd_pmem_region_label_update(struct nd_region 
*nd_region)
        return 0;
 }

+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 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)) {
+                               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];

Unless this gets more complex later, I'd not bother with this local variable.

Thanks Jonathan for review, i have fixed it in V5.


Regards,
Neeraj