Re: [PATCH V3 05/20] nvdimm/namespace_label: Add namespace label changes as per CXL LSA v2.1

Dave Jiang
2025-09-23T21:49:02Z

On 9/17/25 6:41 AM, Neeraj Kumar wrote:
> CXL 3.2 Spec mentions CXL LSA 2.1 Namespace Labels at section 9.13.2.5
> Modified __pmem_label_update function using setter functions to update
> namespace label as per CXL LSA 2.1
>
> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
> ---
> drivers/nvdimm/label.c | 3 +++
> drivers/nvdimm/nd.h | 23 +++++++++++++++++++++++
> 2 files changed, 26 insertions(+)
>
> diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
> index 3235562d0e1c..182f8c9a01bf 100644
> --- a/drivers/nvdimm/label.c
> +++ b/drivers/nvdimm/label.c
> @@ -924,6 +924,7 @@ static int __pmem_label_update(struct nd_region *nd_region,
>
> nd_label = to_label(ndd, slot);
> memset(nd_label, 0, sizeof_namespace_label(ndd));
> + nsl_set_type(ndd, nd_label);
> nsl_set_uuid(ndd, nd_label, nspm->uuid);
> nsl_set_name(ndd, nd_label, nspm->alt_name);
> nsl_set_flags(ndd, nd_label, flags);
> @@ -935,7 +936,9 @@ static int __pmem_label_update(struct nd_region *nd_region,
> nsl_set_lbasize(ndd, nd_label, nspm->lbasize);
> nsl_set_dpa(ndd, nd_label, res->start);
> nsl_set_slot(ndd, nd_label, slot);
> + nsl_set_alignment(ndd, nd_label, 0);
> nsl_set_type_guid(ndd, nd_label, &nd_set->type_guid);
> + nsl_set_region_uuid(ndd, nd_label, NULL);
> nsl_set_claim_class(ndd, nd_label, ndns->claim_class);
> nsl_calculate_checksum(ndd, nd_label);
> nd_dbg_dpa(nd_region, ndd, res, "\n");
> diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h
> index 158809c2be9e..e362611d82cc 100644
> --- a/drivers/nvdimm/nd.h
> +++ b/drivers/nvdimm/nd.h
> @@ -295,6 +295,29 @@ static inline const u8 *nsl_uuid_raw(struct nvdimm_drvdata *ndd,
> return nd_label->efi.uuid;
> }
>
> +static inline void nsl_set_type(struct nvdimm_drvdata *ndd,
> + struct nd_namespace_label *ns_label)
> +{
> + if (ndd->cxl && ns_label)
> + uuid_parse(CXL_NAMESPACE_UUID, (uuid_t *) ns_label->cxl.type);

You can do:
uuid_copy(ns_label->cxl.type, cxl_namespace_uuid);

All the constant UUIDs are preparsed by nd_label_init(). For the entire series you can use those pre-parsed uuid_t and just use uuid_copy() instead of having to do string to uuid_t conversions.

DJ

> +}
> +
> +static inline void nsl_set_alignment(struct nvdimm_drvdata *ndd,
> + struct nd_namespace_label *ns_label,
> + u32 align)
> +{
> + if (ndd->cxl)
> + ns_label->cxl.align = __cpu_to_le32(align);
> +}
> +
> +static inline void nsl_set_region_uuid(struct nvdimm_drvdata *ndd,
> + struct nd_namespace_label *ns_label,
> + const uuid_t *uuid)
> +{
> + if (ndd->cxl && uuid)
> + export_uuid(ns_label->cxl.region_uuid, uuid);
> +}
> +
> bool nsl_validate_type_guid(struct nvdimm_drvdata *ndd,
> struct nd_namespace_label *nd_label, guid_t *guid);
> enum nvdimm_claim_class nsl_get_claim_class(struct nvdimm_drvdata *ndd,