[PATCH V5 07/17] nvdimm/label: Add region label delete support

Neeraj Kumar
2026-01-09T12:45:23Z

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

Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
---
drivers/nvdimm/label.c | 74 ++++++++++++++++++++++++++++++---
drivers/nvdimm/label.h | 1 +
drivers/nvdimm/namespace_devs.c | 7 ++++
drivers/nvdimm/nd.h | 6 +++
include/linux/libnvdimm.h | 1 +
5 files changed, 83 insertions(+), 6 deletions(-)

diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
index 169692dfa12c..2ad148bfe40b 100644
--- a/drivers/nvdimm/label.c
+++ b/drivers/nvdimm/label.c
@@ -1229,7 +1229,8 @@ 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;
@@ -1248,11 +1249,24 @@ 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))
+ continue;
+
+ break;
+ }
+
active--;
slot = to_slot(ndd, label_ent);
nd_label_free_slot(ndd, slot);
@@ -1261,10 +1275,12 @@ static int del_labels(struct nd_mapping *nd_mapping, uuid_t *uuid)

if (uuid_equal(&cxl_namespace_uuid, &label_ent->label_uuid))
label_ent->label = NULL;
+ else
+ label_ent->region_label = NULL;
}
list_splice_tail_init(&list, &nd_mapping->labels);

- if (active == 0) {
+ if ((ltype == NS_LABEL_TYPE) && (active == 0)) {
nd_mapping_free_labels(nd_mapping);
dev_dbg(ndd->dev, "no more active labels\n");
}
@@ -1300,7 +1316,8 @@ int nd_pmem_namespace_label_update(struct nd_region *nd_region,
int count = 0;

if (size == 0) {
- rc = del_labels(nd_mapping, nspm->uuid);
+ rc = del_labels(nd_mapping, nspm->uuid,
+ NS_LABEL_TYPE);
if (rc)
return rc;
continue;
@@ -1385,6 +1402,51 @@ 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++) {
+ rc = del_labels(&nd_region->mapping[i], &nd_set->uuid,
+ RG_LABEL_TYPE);
+ if (rc)
+ return rc;
+ }
+
+ return 0;
+}
+
int __init nd_label_init(void)
{
WARN_ON(guid_parse(NVDIMM_BTT_GUID, &nvdimm_btt_guid));
diff --git a/drivers/nvdimm/label.h b/drivers/nvdimm/label.h
index f11f54056353..80a7f7dd8ba7 100644
--- a/drivers/nvdimm/label.h
+++ b/drivers/nvdimm/label.h
@@ -238,4 +238,5 @@ struct nd_namespace_pmem;
int nd_pmem_namespace_label_update(struct nd_region *nd_region,
struct nd_namespace_pmem *nspm, resource_size_t size);
int nd_pmem_region_label_update(struct nd_region *nd_region);
+int nd_pmem_region_label_delete(struct nd_region *nd_region);
#endif /* __LABEL_H__ */
diff --git a/drivers/nvdimm/namespace_devs.c b/drivers/nvdimm/namespace_devs.c
index 8411f4152319..9047826138be 100644
--- a/drivers/nvdimm/namespace_devs.c
+++ b/drivers/nvdimm/namespace_devs.c
@@ -239,6 +239,13 @@ int nd_region_label_update(struct nd_region *nd_region)
}
EXPORT_SYMBOL_GPL(nd_region_label_update);

+int nd_region_label_delete(struct nd_region *nd_region)
+{
+ guard(nvdimm_bus)(&nd_region->dev);
+ return nd_pmem_region_label_delete(nd_region);
+}
+EXPORT_SYMBOL_GPL(nd_region_label_delete);
+
static int nd_namespace_label_update(struct nd_region *nd_region,
struct device *dev)
{
diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h
index 1b31eee3028e..92a8eabe0792 100644
--- a/drivers/nvdimm/nd.h
+++ b/drivers/nvdimm/nd.h
@@ -337,6 +337,12 @@ static inline bool is_region_label(struct nvdimm_drvdata *ndd,
(uuid_t *)lsa_label->region_label.type);
}

+static inline bool nsl_region_uuid_equal(struct nd_namespace_label *ns_label,
+ const uuid_t *uuid)
+{
+ return uuid_equal((uuid_t *)ns_label->cxl.region_uuid, uuid);
+}
+
static inline bool
region_label_uuid_equal(struct cxl_region_label *region_label,
const uuid_t *uuid)
diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h
index 2c213b9dac66..bbf14a260c93 100644
--- a/include/linux/libnvdimm.h
+++ b/include/linux/libnvdimm.h
@@ -315,6 +315,7 @@ int nvdimm_has_cache(struct nd_region *nd_region);
int nvdimm_in_overwrite(struct nvdimm *nvdimm);
bool is_nvdimm_sync(struct nd_region *nd_region);
int nd_region_label_update(struct nd_region *nd_region);
+int nd_region_label_delete(struct nd_region *nd_region);

static inline int nvdimm_ctl(struct nvdimm *nvdimm, unsigned int cmd, void *buf,
unsigned int buf_len, int *cmd_rc)
--
2.34.1