On 20/06/25 05:40PM, Jonathan Cameron wrote:
On Tue, 17 Jun 2025 18:09:25 +0530
Neeraj Kumar <s.nee...@samsung.com> wrote:
NDD_CXL_LABEL is introduced to set cxl LSA 2.1 label format
Accordingly updated label index version
Signed-off-by: Neeraj Kumar <s.nee...@samsung.com>
A few local comments. I'll need to read on to figure out how this
fits in generally.
---
drivers/nvdimm/dimm.c | 1 +
drivers/nvdimm/dimm_devs.c | 10 ++++++++++
drivers/nvdimm/label.c | 16 ++++++++++++----
drivers/nvdimm/nd.h | 1 +
include/linux/libnvdimm.h | 3 +++
5 files changed, 27 insertions(+), 4 deletions(-)
diff --git a/drivers/nvdimm/dimm.c b/drivers/nvdimm/dimm.c
index 91d9163ee303..8753b5cd91cc 100644
--- a/drivers/nvdimm/dimm.c
+++ b/drivers/nvdimm/dimm.c
@@ -62,6 +62,7 @@ static int nvdimm_probe(struct device *dev)
if (rc < 0)
dev_dbg(dev, "failed to unlock dimm: %d\n", rc);
+ ndd->cxl = nvdimm_check_cxl_label_format(ndd->dev);
/*
* EACCES failures reading the namespace label-area-properties
diff --git a/drivers/nvdimm/dimm_devs.c b/drivers/nvdimm/dimm_devs.c
index 21498d461fde..e8f545f889fd 100644
--- a/drivers/nvdimm/dimm_devs.c
+++ b/drivers/nvdimm/dimm_devs.c
@@ -18,6 +18,16 @@
static DEFINE_IDA(dimm_ida);
+bool nvdimm_check_cxl_label_format(struct device *dev)
+{
+ struct nvdimm *nvdimm = to_nvdimm(dev);
+
+ if (test_bit(NDD_CXL_LABEL, &nvdimm->flags))
+ return true;
+
+ return false;
return test_bit(NDD_CXL_LABEL, &nvdimm->flags);
Unless this is going to get more complex in later patches, in which case
may be fine to ignore this comment.
Okay. I will fix in V1 patch.
+}
+
/*
* Retrieve bus and dimm handle and return if this bus supports
* get_config_data commands
diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
index 082253a3a956..48b5ba90216d 100644
--- a/drivers/nvdimm/label.c
+++ b/drivers/nvdimm/label.c
@@ -687,11 +687,19 @@ 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)
+
+ /* Support CXL LSA 2.1 label format */
Might be good to sprinkle some extra details in the references.
E.g. CXL r3.2 Table 9-9 Label Index Block Layout
Sure, I will update it in V1
+ if (ndd->cxl) {
+ 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);
Same for these. Case of making reviewers jobs easier by
giving them breadcrumb trails to follow.
Sure, I will update it in V1
+ if (sizeof_namespace_label(ndd) < 256)
+ nsindex->minor = __cpu_to_le16(1);
+ else
+ 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/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h
index 5ca06e9a2d29..304f0e9904f1 100644
--- a/drivers/nvdimm/nd.h
+++ b/drivers/nvdimm/nd.h
@@ -522,6 +522,7 @@ void nvdimm_set_labeling(struct device *dev);
void nvdimm_set_locked(struct device *dev);
void nvdimm_clear_locked(struct device *dev);
int nvdimm_security_setup_events(struct device *dev);
+bool nvdimm_check_cxl_label_format(struct device *dev);
#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 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,
+
/* need to set a limit somewhere, but yes, this is likely overkill */
ND_IOCTL_MAX_BUFLEN = SZ_4M,
ND_CMD_MAX_ELEM = 5,
