On 13/08/25 02:12PM, Jonathan Cameron wrote:
On Wed, 30 Jul 2025 17:41:50 +0530
Neeraj Kumar <s.nee...@samsung.com> wrote:
Prior to LSA 2.1 version, LSA contain only namespace labels. LSA 2.1
introduced in CXL 2.0 Spec, which contain region label along with
namespace label.
NDD_LABELING flag is used for namespace. Introduced NDD_CXL_LABEL
flag for region label. Based on these flags nvdimm driver performs
operation on namespace label or region label.
NDD_CXL_LABEL will be utilized by cxl driver to enable LSA2.1 region
label support
Accordingly updated label index version
Signed-off-by: Neeraj Kumar <s.nee...@samsung.com>
Hi Neeraj,
A few comments inline.
diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
index 04f4a049599a..7a011ee02d79 100644
--- a/drivers/nvdimm/label.c
+++ b/drivers/nvdimm/label.c
@@ -688,11 +688,25 @@ static int nd_label_write_index(struct nvdimm_drvdata
*ndd, int index, u32 seq,
- (unsigned long) to_namespace_index(ndd, 0);
nsindex->labeloff = __cpu_to_le64(offset);
nsindex->nslot = __cpu_to_le32(nslot);
- nsindex->major = __cpu_to_le16(1);
- if (sizeof_namespace_label(ndd) < 256)
+
+ /* Set LSA Label Index Version */
+ if (ndd->cxl) {
+ /* CXL r3.2 Spec: Table 9-9 Label Index Block Layout */
+ nsindex->major = __cpu_to_le16(2);
nsindex->minor = __cpu_to_le16(1);
- else
- nsindex->minor = __cpu_to_le16(2);
+ } else {
+ nsindex->major = __cpu_to_le16(1);
+ /*
+ * NVDIMM Namespace Specification
+ * Table 2: Namespace Label Index Block Fields
+ */
+ if (sizeof_namespace_label(ndd) < 256)
+ nsindex->minor = __cpu_to_le16(1);
+ else
+ /* UEFI Specification 2.7: Label Index Block Definitions */
Odd comment alignment. Either put it on the else so
else /* UEFI 2.7: Label Index Block Defintions */
or indent it an extra tab
else
/* UEFI 2.7: Label Index Block Definitions */
Thanks Jonathan, I will fix it in next patch-set
+ nsindex->minor = __cpu_to_le16(2);
+ }
+
nsindex->checksum = __cpu_to_le64(0);
if (flags & ND_NSINDEX_INIT) {
unsigned long *free = (unsigned long *) nsindex->free;
diff --git a/include/linux/libnvdimm.h b/include/linux/libnvdimm.h
index e772aae71843..0a55900842c8 100644
--- a/include/linux/libnvdimm.h
+++ b/include/linux/libnvdimm.h
@@ -44,6 +44,9 @@ enum {
/* dimm provider wants synchronous registration by __nvdimm_create() */
NDD_REGISTER_SYNC = 8,
+ /* dimm supports region labels (LSA Format 2.1) */
+ NDD_CXL_LABEL = 9,
This enum is 'curious'. It combined flags from a bunch of different
flags fields and some stuff that are nothing to do with flags.
Anyhow, putting that aside I'd either rename it to something like
NDD_REGION_LABELING (similar to NDD_LABELING that is there for namespace labels
or just have it a meaning it is LSA Format 2.1 and drop the fact htat
also means region labels are supported.
Combination of a comment that talks about one thing and a definition name
that doesn't associate with it seems confusing to me.
Jonathan
Sure, I will rename it in next patch-set
Regards,
Neeraj
+
/* need to set a limit somewhere, but yes, this is likely overkill */
ND_IOCTL_MAX_BUFLEN = SZ_4M,
ND_CMD_MAX_ELEM = 5,
