[PATCH V4 01/17] nvdimm/label: Introduce NDD_REGION_LABELING flag to set region label

[Neeraj Kumar <s.neeraj@samsung.com>]

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_REGION_LABELING
flag for region label. Based on these flags nvdimm driver performs
operation on namespace label or region label.

NDD_REGION_LABELING will be utilized by cxl driver to enable LSA 2.1
region label support

Accordingly updated label index version

Reviewed-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Neeraj Kumar <s.neeraj@samsung.com>
---
 drivers/nvdimm/dimm.c      |  1 +
 drivers/nvdimm/dimm_devs.c |  7 +++++++
 drivers/nvdimm/label.c     | 21 +++++++++++++++++----
 drivers/nvdimm/nd.h        |  1 +
 include/linux/libnvdimm.h  |  3 +++
 5 files changed, 29 insertions(+), 4 deletions(-)

diff --git a/drivers/nvdimm/dimm.c b/drivers/nvdimm/dimm.c
index 2f6c26cc6a3e..07f5c5d5e537 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_region_label_supported(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 e1349ef5f8fd..3363a97cc5b5 100644
--- a/drivers/nvdimm/dimm_devs.c
+++ b/drivers/nvdimm/dimm_devs.c
@@ -18,6 +18,13 @@
 
 static DEFINE_IDA(dimm_ida);
 
+bool nvdimm_region_label_supported(struct device *dev)
+{
+	struct nvdimm *nvdimm = to_nvdimm(dev);
+
+	return test_bit(NDD_REGION_LABELING, &nvdimm->flags);
+}
+
 /*
  * 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 04f4a049599a..0a9b6c5cb2c3 100644
--- a/drivers/nvdimm/label.c
+++ b/drivers/nvdimm/label.c
@@ -688,11 +688,24 @@ 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: 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 2.7: Label Index Block Definitions */
+			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 b199eea3260e..f631bd84d6f0 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_region_label_supported(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 28f086c4a187..5696715c33bb 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_REGION_LABELING = 9,
+
 	/* need to set a limit somewhere, but yes, this is likely overkill */
 	ND_IOCTL_MAX_BUFLEN = SZ_4M,
 	ND_CMD_MAX_ELEM = 5,
-- 
2.34.1