[v2] Add CXL LSA 2.1 format support in nvdimm and cxl pmem

[PATCH V2 09/20] nvdimm/namespace_label: Skip region label during ns label DPA reservation

Posted by Neeraj Kumar 2 months, 1 week ago

If Namespace label is present in LSA during nvdimm_probe then DPA
reservation is required. But this reservation is not required by region
label. Therefore if LSA scanning finds any region label, skip it.

Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
---
 drivers/nvdimm/label.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
index c4748e30f2b6..064a945dcdd1 100644
--- a/drivers/nvdimm/label.c
+++ b/drivers/nvdimm/label.c
@@ -452,6 +452,10 @@ int nd_label_reserve_dpa(struct nvdimm_drvdata *ndd)
 		lsa_label = to_label(ndd, slot);
 		nd_label = &lsa_label->ns_label;
 
+		/* skip region label, dpa reservation for ns label only */
+		if (is_region_label(ndd, lsa_label))
+			continue;
+
 		if (!slot_valid(ndd, lsa_label, slot))
 			continue;
 
-- 
2.34.1

Re: [PATCH V2 09/20] nvdimm/namespace_label: Skip region label during ns label DPA reservation

Posted by Jonathan Cameron 1 month, 3 weeks ago

On Wed, 30 Jul 2025 17:41:58 +0530
Neeraj Kumar <s.neeraj@samsung.com> wrote:

> If Namespace label is present in LSA during nvdimm_probe then DPA
> reservation is required. But this reservation is not required by region
> label. Therefore if LSA scanning finds any region label, skip it.
> 
> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
> ---
>  drivers/nvdimm/label.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
> index c4748e30f2b6..064a945dcdd1 100644
> --- a/drivers/nvdimm/label.c
> +++ b/drivers/nvdimm/label.c
> @@ -452,6 +452,10 @@ int nd_label_reserve_dpa(struct nvdimm_drvdata *ndd)
>  		lsa_label = to_label(ndd, slot);
>  		nd_label = &lsa_label->ns_label;
>  
> +		/* skip region label, dpa reservation for ns label only */
Confusing comment and not clear if skip applies just to region label or
to dpa reservation as well.

		/* Skip region label.  DPA reservation is for NS label only. */

or something along those lines (assuming I have understood this right!)
> +		if (is_region_label(ndd, lsa_label))
> +			continue;
> +
>  		if (!slot_valid(ndd, lsa_label, slot))
>  			continue;
>

Re: [PATCH V2 09/20] nvdimm/namespace_label: Skip region label during ns label DPA reservation

Posted by Neeraj Kumar 1 month ago

On 13/08/25 04:09PM, Jonathan Cameron wrote:
>On Wed, 30 Jul 2025 17:41:58 +0530
>Neeraj Kumar <s.neeraj@samsung.com> wrote:
>
>> If Namespace label is present in LSA during nvdimm_probe then DPA
>> reservation is required. But this reservation is not required by region
>> label. Therefore if LSA scanning finds any region label, skip it.
>>
>> Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
>> ---
>>  drivers/nvdimm/label.c | 4 ++++
>>  1 file changed, 4 insertions(+)
>>
>> diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
>> index c4748e30f2b6..064a945dcdd1 100644
>> --- a/drivers/nvdimm/label.c
>> +++ b/drivers/nvdimm/label.c
>> @@ -452,6 +452,10 @@ int nd_label_reserve_dpa(struct nvdimm_drvdata *ndd)
>>  		lsa_label = to_label(ndd, slot);
>>  		nd_label = &lsa_label->ns_label;
>>
>> +		/* skip region label, dpa reservation for ns label only */
>Confusing comment and not clear if skip applies just to region label or
>to dpa reservation as well.
>
>		/* Skip region label.  DPA reservation is for NS label only. */
>
>or something along those lines (assuming I have understood this right!)

Sure Jonathan, I will fix it in next patch-set


Regards,
Neeraj