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.nee...@samsung.com> 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.nee...@samsung.com>
---
 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;
+}