Re: [PATCH V4 08/17] nvdimm/label: Preserve cxl region information from region label
On 19/11/25 01:13PM, Dave Jiang wrote: On 11/19/25 12:52 AM, Neeraj Kumar wrote: Preserve region information from region label during nvdimm_probe. This preserved region information is used for creating cxl region to achieve region persistency across reboot. Signed-off-by: Neeraj Kumar Reviewed-by: Dave Jiang Assume there's a plan to add >1 region labels preservation in the next step? Thanks Dave for RB tag. Yes, I will prepare in next patch series. Regards, Neeraj
Re: [PATCH V4 08/17] nvdimm/label: Preserve cxl region information from region label
On 17/12/25 03:09PM, Jonathan Cameron wrote:
On Wed, 19 Nov 2025 13:22:46 +0530
Neeraj Kumar wrote:
Preserve region information from region label during nvdimm_probe. This
preserved region information is used for creating cxl region to achieve
region persistency across reboot.
Signed-off-by: Neeraj Kumar
Trivial comments inline. As Dave asked, what's the plan for multiple?
Multi-interleave support will require some more efforts on top of this change
So will take it in another series.
Yes, I will prepare in next patch series
Add some brief notes to the patch description on this.
Yes, I have updated it in commit description
Thanks,
Jonathan
---
drivers/nvdimm/dimm.c | 4
drivers/nvdimm/label.c| 40 +++
drivers/nvdimm/nd-core.h | 2 ++
drivers/nvdimm/nd.h | 1 +
include/linux/libnvdimm.h | 14 ++
5 files changed, 61 insertions(+)
+int nvdimm_cxl_region_preserve(struct nvdimm_drvdata *ndd)
+{
+ struct nvdimm *nvdimm = to_nvdimm(ndd->dev);
+ struct cxl_pmem_region_params *p = &nvdimm->cxl_region_params;
+ struct nd_namespace_index *nsindex;
+ unsigned long *free;
+ u32 nslot, slot;
+
+ if (!preamble_current(ndd, &nsindex, &free, &nslot))
+ return 0; /* no label, nothing to preserve */
+
+ for_each_clear_bit_le(slot, free, nslot) {
+ union nd_lsa_label *lsa_label;
+ struct cxl_region_label *region_label;
+ uuid_t *region_uuid;
+
+ lsa_label = to_lsa_label(ndd, slot);
+ region_label = &lsa_label->region_label;
+ region_uuid = (uuid_t *) ®ion_label->type;
+
union nd_lsa_label *lsa_label = to_lsa_label(ndd, slot);
struct cxl_region_label *region_label =
&lsa_label->region_label;
//I'd go long on thi sone as only just over 80 and helps readability.
uuid_t *region_uuid = (uuid_t *)®ion_label->type;
Saves a fine lines and there doesn't seem to be an obvious reason
not to do so.
I have fixed in V5, Will be sending it soon.
Regards,
Neeraj
Re: [PATCH V4 08/17] nvdimm/label: Preserve cxl region information from region label
On Wed, 19 Nov 2025 13:22:46 +0530
Neeraj Kumar wrote:
> Preserve region information from region label during nvdimm_probe. This
> preserved region information is used for creating cxl region to achieve
> region persistency across reboot.
>
> Signed-off-by: Neeraj Kumar
Trivial comments inline. As Dave asked, what's the plan for multiple?
Add some brief notes to the patch description on this.
Thanks,
Jonathan
> ---
> drivers/nvdimm/dimm.c | 4
> drivers/nvdimm/label.c| 40 +++
> drivers/nvdimm/nd-core.h | 2 ++
> drivers/nvdimm/nd.h | 1 +
> include/linux/libnvdimm.h | 14 ++
> 5 files changed, 61 insertions(+)
>
> diff --git a/drivers/nvdimm/dimm.c b/drivers/nvdimm/dimm.c
> index 07f5c5d5e537..590ec883903d 100644
> --- a/drivers/nvdimm/dimm.c
> +++ b/drivers/nvdimm/dimm.c
> @@ -107,6 +107,10 @@ static int nvdimm_probe(struct device *dev)
> if (rc)
> goto err;
>
> + /* Preserve cxl region info if available */
> + if (ndd->cxl)
> + nvdimm_cxl_region_preserve(ndd);
> +
> return 0;
>
> err:
> diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
> index da55ecd95e2f..0f8aea61b504 100644
> --- a/drivers/nvdimm/label.c
> +++ b/drivers/nvdimm/label.c
> @@ -490,6 +490,46 @@ int nd_label_reserve_dpa(struct nvdimm_drvdata *ndd)
> return 0;
> }
>
> +int nvdimm_cxl_region_preserve(struct nvdimm_drvdata *ndd)
> +{
> + struct nvdimm *nvdimm = to_nvdimm(ndd->dev);
> + struct cxl_pmem_region_params *p = &nvdimm->cxl_region_params;
> + struct nd_namespace_index *nsindex;
> + unsigned long *free;
> + u32 nslot, slot;
> +
> + if (!preamble_current(ndd, &nsindex, &free, &nslot))
> + return 0; /* no label, nothing to preserve */
> +
> + for_each_clear_bit_le(slot, free, nslot) {
> + union nd_lsa_label *lsa_label;
> + struct cxl_region_label *region_label;
> + uuid_t *region_uuid;
> +
> + lsa_label = to_lsa_label(ndd, slot);
> + region_label = &lsa_label->region_label;
> + region_uuid = (uuid_t *) ®ion_label->type;
> +
union nd_lsa_label *lsa_label = to_lsa_label(ndd, slot);
struct cxl_region_label *region_label =
&lsa_label->region_label;
//I'd go long on thi sone as only just over 80 and helps readability.
uuid_t *region_uuid = (uuid_t *)®ion_label->type;
Saves a fine lines and there doesn't seem to be an obvious reason
not to do so.
> + /* TODO: Currently preserving only one region */
> + if (uuid_equal(&cxl_region_uuid, region_uuid)) {
> + nvdimm->is_region_label = true;
> + import_uuid(&p->uuid, region_label->uuid);
> + p->flags = __le32_to_cpu(region_label->flags);
> + p->nlabel = __le16_to_cpu(region_label->nlabel);
> + p->position = __le16_to_cpu(region_label->position);
> + p->dpa = __le64_to_cpu(region_label->dpa);
> + p->rawsize = __le64_to_cpu(region_label->rawsize);
> + p->hpa = __le64_to_cpu(region_label->hpa);
> + p->slot = __le32_to_cpu(region_label->slot);
> + p->ig = __le32_to_cpu(region_label->ig);
> + p->align = __le32_to_cpu(region_label->align);
> + break;
> + }
> + }
> +
> + return 0;
> +}
Re: [PATCH V4 08/17] nvdimm/label: Preserve cxl region information from region label
On 11/19/25 12:52 AM, Neeraj Kumar wrote:
> Preserve region information from region label during nvdimm_probe. This
> preserved region information is used for creating cxl region to achieve
> region persistency across reboot.
>
> Signed-off-by: Neeraj Kumar
Reviewed-by: Dave Jiang
Assume there's a plan to add >1 region labels preservation in the next step?
> ---
> drivers/nvdimm/dimm.c | 4
> drivers/nvdimm/label.c| 40 +++
> drivers/nvdimm/nd-core.h | 2 ++
> drivers/nvdimm/nd.h | 1 +
> include/linux/libnvdimm.h | 14 ++
> 5 files changed, 61 insertions(+)
>
> diff --git a/drivers/nvdimm/dimm.c b/drivers/nvdimm/dimm.c
> index 07f5c5d5e537..590ec883903d 100644
> --- a/drivers/nvdimm/dimm.c
> +++ b/drivers/nvdimm/dimm.c
> @@ -107,6 +107,10 @@ static int nvdimm_probe(struct device *dev)
> if (rc)
> goto err;
>
> + /* Preserve cxl region info if available */
> + if (ndd->cxl)
> + nvdimm_cxl_region_preserve(ndd);
> +
> return 0;
>
> err:
> diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
> index da55ecd95e2f..0f8aea61b504 100644
> --- a/drivers/nvdimm/label.c
> +++ b/drivers/nvdimm/label.c
> @@ -490,6 +490,46 @@ int nd_label_reserve_dpa(struct nvdimm_drvdata *ndd)
> return 0;
> }
>
> +int nvdimm_cxl_region_preserve(struct nvdimm_drvdata *ndd)
> +{
> + struct nvdimm *nvdimm = to_nvdimm(ndd->dev);
> + struct cxl_pmem_region_params *p = &nvdimm->cxl_region_params;
> + struct nd_namespace_index *nsindex;
> + unsigned long *free;
> + u32 nslot, slot;
> +
> + if (!preamble_current(ndd, &nsindex, &free, &nslot))
> + return 0; /* no label, nothing to preserve */
> +
> + for_each_clear_bit_le(slot, free, nslot) {
> + union nd_lsa_label *lsa_label;
> + struct cxl_region_label *region_label;
> + uuid_t *region_uuid;
> +
> + lsa_label = to_lsa_label(ndd, slot);
> + region_label = &lsa_label->region_label;
> + region_uuid = (uuid_t *) ®ion_label->type;
> +
> + /* TODO: Currently preserving only one region */
> + if (uuid_equal(&cxl_region_uuid, region_uuid)) {
> + nvdimm->is_region_label = true;
> + import_uuid(&p->uuid, region_label->uuid);
> + p->flags = __le32_to_cpu(region_label->flags);
> + p->nlabel = __le16_to_cpu(region_label->nlabel);
> + p->position = __le16_to_cpu(region_label->position);
> + p->dpa = __le64_to_cpu(region_label->dpa);
> + p->rawsize = __le64_to_cpu(region_label->rawsize);
> + p->hpa = __le64_to_cpu(region_label->hpa);
> + p->slot = __le32_to_cpu(region_label->slot);
> + p->ig = __le32_to_cpu(region_label->ig);
> + p->align = __le32_to_cpu(region_label->align);
> + break;
> + }
> + }
> +
> + return 0;
> +}
> +
> int nd_label_data_init(struct nvdimm_drvdata *ndd)
> {
> size_t config_size, read_size, max_xfer, offset;
> diff --git a/drivers/nvdimm/nd-core.h b/drivers/nvdimm/nd-core.h
> index bfc6bfeb6e24..a73fac81531e 100644
> --- a/drivers/nvdimm/nd-core.h
> +++ b/drivers/nvdimm/nd-core.h
> @@ -46,6 +46,8 @@ struct nvdimm {
> } sec;
> struct delayed_work dwork;
> const struct nvdimm_fw_ops *fw_ops;
> + bool is_region_label;
> + struct cxl_pmem_region_params cxl_region_params;
> };
>
> static inline unsigned long nvdimm_security_flags(
> diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h
> index b241a0b2e314..281d30dd9ba0 100644
> --- a/drivers/nvdimm/nd.h
> +++ b/drivers/nvdimm/nd.h
> @@ -600,6 +600,7 @@ void nvdimm_set_locked(struct device *dev);
> void nvdimm_clear_locked(struct device *dev);
> int nvdimm_security_setup_events(struct device *dev);
> bool nvdimm_region_label_supported(struct device *dev);
> +int nvdimm_cxl_region_preserve(struct nvdimm_drvdata *ndd);
> #if IS_ENABLED(CONFIG_NVDIMM_KEYS)
> int nvdimm_security_unlock(struct device *dev);
> #else
> diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h
> index bbf14a260c93..07ea2e3f821a 100644
> --- a/include/linux/libnvdimm.h
> +++ b/include/linux/libnvdimm.h
> @@ -108,6 +108,20 @@ struct nd_cmd_desc {
> int out_sizes[ND_CMD_MAX_ELEM];
> };
>
> +struct cxl_pmem_region_params {
> + uuid_t uuid;
> + u32 flags;
> + u16 nlabel;
> + u16 position;
> + u64 dpa;
> + u64 rawsize;
> + u64 hpa;
> + u32 slot;
> + u32 ig;
> + u32 align;
> + int nr_targets;
> +};
> +
> struct nd_interleave_set {
> /* v1.1 definition of the interleave-set-cookie algorithm */
> u64 cookie1;
