Merge tag 'cxl-for-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl

Pull cxl updates from Dan Williams:
 "More preparation and plumbing work in the CXL subsystem.

  From an end user perspective the highlight here is lighting up the CXL
  Persistent Memory related commands (label read / write) with the
  generic ioctl() front-end in LIBNVDIMM.

  Otherwise, the ability to instantiate new persistent and volatile
  memory regions is still on track for v5.17.

  Summary:

   - Fix support for platforms that do not enumerate every ACPI0016 (CXL
     Host Bridge) in the CHBS (ACPI Host Bridge Structure).

   - Introduce a common pci_find_dvsec_capability() helper, clean up
     open coded implementations in various drivers.

   - Add 'cxl_test' for regression testing CXL subsystem ABIs.
     'cxl_test' is a module built from tools/testing/cxl/ that mocks up
     a CXL topology to augment the nascent support for emulation of CXL
     devices in QEMU.

   - Convert libnvdimm to use the uuid API.

   - Complete the definition of CXL namespace labels in libnvdimm.

   - Tunnel libnvdimm label operations from nd_ioctl() back to the CXL
     mailbox driver. Enable 'ndctl {read,write}-labels' for CXL.

   - Continue to sort and refactor functionality into distinct driver
     and core-infrastructure buckets. For example, mailbox handling is
     now a generic core capability consumed by the PCI and cxl_test
     drivers"

* tag 'cxl-for-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl: (34 commits)
  ocxl: Use pci core's DVSEC functionality
  cxl/pci: Use pci core's DVSEC functionality
  PCI: Add pci_find_dvsec_capability to find designated VSEC
  cxl/pci: Split cxl_pci_setup_regs()
  cxl/pci: Add @base to cxl_register_map
  cxl/pci: Make more use of cxl_register_map
  cxl/pci: Remove pci request/release regions
  cxl/pci: Fix NULL vs ERR_PTR confusion
  cxl/pci: Remove dev_dbg for unknown register blocks
  cxl/pci: Convert register block identifiers to an enum
  cxl/acpi: Do not fail cxl_acpi_probe() based on a missing CHBS
  cxl/pci: Disambiguate cxl_pci further from cxl_mem
  Documentation/cxl: Add bus internal docs
  cxl/core: Split decoder setup into alloc + add
  tools/testing/cxl: Introduce a mock memory device + driver
  cxl/mbox: Move command definitions to common location
  cxl/bus: Populate the target list at decoder create
  tools/testing/cxl: Introduce a mocked-up CXL port hierarchy
  cxl/pmem: Add support for multiple nvdimm-bridge objects
  cxl/pmem: Translate NVDIMM label commands to CXL label commands
  ...

9 files changed, 421 insertions, 164 deletions

diff --git a/drivers/nvdimm/btt.c b/drivers/nvdimm/btt.c
index 4295fa809420..f10a50ffa047 100644
--- a/drivers/nvdimm/btt.c
+++ b/drivers/nvdimm/btt.c
@@ -973,7 +973,7 @@ static int btt_arena_write_layout(struct arena_info *arena)
 	u64 sum;
 	struct btt_sb *super;
 	struct nd_btt *nd_btt = arena->nd_btt;
-	const u8 *parent_uuid = nd_dev_to_uuid(&nd_btt->ndns->dev);
+	const uuid_t *parent_uuid = nd_dev_to_uuid(&nd_btt->ndns->dev);
 
 	ret = btt_map_init(arena);
 	if (ret)
@@ -988,8 +988,8 @@ static int btt_arena_write_layout(struct arena_info *arena)
 		return -ENOMEM;
 
 	strncpy(super->signature, BTT_SIG, BTT_SIG_LEN);
-	memcpy(super->uuid, nd_btt->uuid, 16);
-	memcpy(super->parent_uuid, parent_uuid, 16);
+	export_uuid(super->uuid, nd_btt->uuid);
+	export_uuid(super->parent_uuid, parent_uuid);
 	super->flags = cpu_to_le32(arena->flags);
 	super->version_major = cpu_to_le16(arena->version_major);
 	super->version_minor = cpu_to_le16(arena->version_minor);
@@ -1574,7 +1574,8 @@ static void btt_blk_cleanup(struct btt *btt)
  * Pointer to a new struct btt on success, NULL on failure.
  */
 static struct btt *btt_init(struct nd_btt *nd_btt, unsigned long long rawsize,
-		u32 lbasize, u8 *uuid, struct nd_region *nd_region)
+			    u32 lbasize, uuid_t *uuid,
+			    struct nd_region *nd_region)
 {
 	int ret;
 	struct btt *btt;
@@ -1693,7 +1694,7 @@ int nvdimm_namespace_attach_btt(struct nd_namespace_common *ndns)
 	}
 	nd_region = to_nd_region(nd_btt->dev.parent);
 	btt = btt_init(nd_btt, rawsize, nd_btt->lbasize, nd_btt->uuid,
-			nd_region);
+		       nd_region);
 	if (!btt)
 		return -ENOMEM;
 	nd_btt->btt = btt;
diff --git a/drivers/nvdimm/btt_devs.c b/drivers/nvdimm/btt_devs.c
index 05feb97e11ce..8b52e5144f08 100644
--- a/drivers/nvdimm/btt_devs.c
+++ b/drivers/nvdimm/btt_devs.c
@@ -180,8 +180,8 @@ bool is_nd_btt(struct device *dev)
 EXPORT_SYMBOL(is_nd_btt);
 
 static struct device *__nd_btt_create(struct nd_region *nd_region,
-		unsigned long lbasize, u8 *uuid,
-		struct nd_namespace_common *ndns)
+				      unsigned long lbasize, uuid_t *uuid,
+				      struct nd_namespace_common *ndns)
 {
 	struct nd_btt *nd_btt;
 	struct device *dev;
@@ -244,14 +244,16 @@ struct device *nd_btt_create(struct nd_region *nd_region)
  */
 bool nd_btt_arena_is_valid(struct nd_btt *nd_btt, struct btt_sb *super)
 {
-	const u8 *parent_uuid = nd_dev_to_uuid(&nd_btt->ndns->dev);
+	const uuid_t *ns_uuid = nd_dev_to_uuid(&nd_btt->ndns->dev);
+	uuid_t parent_uuid;
 	u64 checksum;
 
 	if (memcmp(super->signature, BTT_SIG, BTT_SIG_LEN) != 0)
 		return false;
 
-	if (!guid_is_null((guid_t *)&super->parent_uuid))
-		if (memcmp(super->parent_uuid, parent_uuid, 16) != 0)
+	import_uuid(&parent_uuid, super->parent_uuid);
+	if (!uuid_is_null(&parent_uuid))
+		if (!uuid_equal(&parent_uuid, ns_uuid))
 			return false;
 
 	checksum = le64_to_cpu(super->checksum);
@@ -319,7 +321,7 @@ static int __nd_btt_probe(struct nd_btt *nd_btt,
 		return rc;
 
 	nd_btt->lbasize = le32_to_cpu(btt_sb->external_lbasize);
-	nd_btt->uuid = kmemdup(btt_sb->uuid, 16, GFP_KERNEL);
+	nd_btt->uuid = kmemdup(&btt_sb->uuid, sizeof(uuid_t), GFP_KERNEL);
 	if (!nd_btt->uuid)
 		return -ENOMEM;
 
diff --git a/drivers/nvdimm/core.c b/drivers/nvdimm/core.c
index 6a45fa91e8a3..69a03358817f 100644
--- a/drivers/nvdimm/core.c
+++ b/drivers/nvdimm/core.c
@@ -207,38 +207,6 @@ struct device *to_nvdimm_bus_dev(struct nvdimm_bus *nvdimm_bus)
 }
 EXPORT_SYMBOL_GPL(to_nvdimm_bus_dev);
 
-static bool is_uuid_sep(char sep)
-{
-	if (sep == '\n' || sep == '-' || sep == ':' || sep == '\0')
-		return true;
-	return false;
-}
-
-static int nd_uuid_parse(struct device *dev, u8 *uuid_out, const char *buf,
-		size_t len)
-{
-	const char *str = buf;
-	u8 uuid[16];
-	int i;
-
-	for (i = 0; i < 16; i++) {
-		if (!isxdigit(str[0]) || !isxdigit(str[1])) {
-			dev_dbg(dev, "pos: %d buf[%zd]: %c buf[%zd]: %c\n",
-					i, str - buf, str[0],
-					str + 1 - buf, str[1]);
-			return -EINVAL;
-		}
-
-		uuid[i] = (hex_to_bin(str[0]) << 4) | hex_to_bin(str[1]);
-		str += 2;
-		if (is_uuid_sep(*str))
-			str++;
-	}
-
-	memcpy(uuid_out, uuid, sizeof(uuid));
-	return 0;
-}
-
 /**
  * nd_uuid_store: common implementation for writing 'uuid' sysfs attributes
  * @dev: container device for the uuid property
@@ -249,21 +217,21 @@ static int nd_uuid_parse(struct device *dev, u8 *uuid_out, const char *buf,
  * (driver detached)
  * LOCKING: expects nd_device_lock() is held on entry
  */
-int nd_uuid_store(struct device *dev, u8 **uuid_out, const char *buf,
+int nd_uuid_store(struct device *dev, uuid_t **uuid_out, const char *buf,
 		size_t len)
 {
-	u8 uuid[16];
+	uuid_t uuid;
 	int rc;
 
 	if (dev->driver)
 		return -EBUSY;
 
-	rc = nd_uuid_parse(dev, uuid, buf, len);
+	rc = uuid_parse(buf, &uuid);
 	if (rc)
 		return rc;
 
 	kfree(*uuid_out);
-	*uuid_out = kmemdup(uuid, sizeof(uuid), GFP_KERNEL);
+	*uuid_out = kmemdup(&uuid, sizeof(uuid), GFP_KERNEL);
 	if (!(*uuid_out))
 		return -ENOMEM;
 
diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
index 7f473f9db300..5ec9a4023df9 100644
--- a/drivers/nvdimm/label.c
+++ b/drivers/nvdimm/label.c
@@ -17,6 +17,14 @@ static guid_t nvdimm_btt2_guid;
 static guid_t nvdimm_pfn_guid;
 static guid_t nvdimm_dax_guid;
 
+static uuid_t nvdimm_btt_uuid;
+static uuid_t nvdimm_btt2_uuid;
+static uuid_t nvdimm_pfn_uuid;
+static uuid_t nvdimm_dax_uuid;
+
+static uuid_t cxl_region_uuid;
+static uuid_t cxl_namespace_uuid;
+
 static const char NSINDEX_SIGNATURE[] = "NAMESPACE_INDEX\0";
 
 static u32 best_seq(u32 a, u32 b)
@@ -321,7 +329,8 @@ static bool preamble_index(struct nvdimm_drvdata *ndd, int idx,
 	return true;
 }
 
-char *nd_label_gen_id(struct nd_label_id *label_id, u8 *uuid, u32 flags)
+char *nd_label_gen_id(struct nd_label_id *label_id, const uuid_t *uuid,
+		      u32 flags)
 {
 	if (!label_id || !uuid)
 		return NULL;
@@ -351,7 +360,7 @@ static bool nsl_validate_checksum(struct nvdimm_drvdata *ndd,
 {
 	u64 sum, sum_save;
 
-	if (!namespace_label_has(ndd, checksum))
+	if (!ndd->cxl && !efi_namespace_label_has(ndd, checksum))
 		return true;
 
 	sum_save = nsl_get_checksum(ndd, nd_label);
@@ -366,7 +375,7 @@ static void nsl_calculate_checksum(struct nvdimm_drvdata *ndd,
 {
 	u64 sum;
 
-	if (!namespace_label_has(ndd, checksum))
+	if (!ndd->cxl && !efi_namespace_label_has(ndd, checksum))
 		return;
 	nsl_set_checksum(ndd, nd_label, 0);
 	sum = nd_fletcher64(nd_label, sizeof_namespace_label(ndd), 1);
@@ -400,9 +409,9 @@ int nd_label_reserve_dpa(struct nvdimm_drvdata *ndd)
 		struct nvdimm *nvdimm = to_nvdimm(ndd->dev);
 		struct nd_namespace_label *nd_label;
 		struct nd_region *nd_region = NULL;
-		u8 label_uuid[NSLABEL_UUID_LEN];
 		struct nd_label_id label_id;
 		struct resource *res;
+		uuid_t label_uuid;
 		u32 flags;
 
 		nd_label = to_label(ndd, slot);
@@ -410,11 +419,11 @@ int nd_label_reserve_dpa(struct nvdimm_drvdata *ndd)
 		if (!slot_valid(ndd, nd_label, slot))
 			continue;
 
-		memcpy(label_uuid, nd_label->uuid, NSLABEL_UUID_LEN);
+		nsl_get_uuid(ndd, nd_label, &label_uuid);
 		flags = nsl_get_flags(ndd, nd_label);
 		if (test_bit(NDD_NOBLK, &nvdimm->flags))
 			flags &= ~NSLABEL_FLAG_LOCAL;
-		nd_label_gen_id(&label_id, label_uuid, flags);
+		nd_label_gen_id(&label_id, &label_uuid, flags);
 		res = nvdimm_allocate_dpa(ndd, &label_id,
 					  nsl_get_dpa(ndd, nd_label),
 					  nsl_get_rawsize(ndd, nd_label));
@@ -724,7 +733,7 @@ static unsigned long nd_label_offset(struct nvdimm_drvdata *ndd,
 		- (unsigned long) to_namespace_index(ndd, 0);
 }
 
-static enum nvdimm_claim_class to_nvdimm_cclass(guid_t *guid)
+static enum nvdimm_claim_class guid_to_nvdimm_cclass(guid_t *guid)
 {
 	if (guid_equal(guid, &nvdimm_btt_guid))
 		return NVDIMM_CCLASS_BTT;
@@ -740,6 +749,23 @@ static enum nvdimm_claim_class to_nvdimm_cclass(guid_t *guid)
 	return NVDIMM_CCLASS_UNKNOWN;
 }
 
+/* CXL labels store UUIDs instead of GUIDs for the same data */
+static enum nvdimm_claim_class uuid_to_nvdimm_cclass(uuid_t *uuid)
+{
+	if (uuid_equal(uuid, &nvdimm_btt_uuid))
+		return NVDIMM_CCLASS_BTT;
+	else if (uuid_equal(uuid, &nvdimm_btt2_uuid))
+		return NVDIMM_CCLASS_BTT2;
+	else if (uuid_equal(uuid, &nvdimm_pfn_uuid))
+		return NVDIMM_CCLASS_PFN;
+	else if (uuid_equal(uuid, &nvdimm_dax_uuid))
+		return NVDIMM_CCLASS_DAX;
+	else if (uuid_equal(uuid, &uuid_null))
+		return NVDIMM_CCLASS_NONE;
+
+	return NVDIMM_CCLASS_UNKNOWN;
+}
+
 static const guid_t *to_abstraction_guid(enum nvdimm_claim_class claim_class,
 	guid_t *target)
 {
@@ -761,6 +787,28 @@ static const guid_t *to_abstraction_guid(enum nvdimm_claim_class claim_class,
 		return &guid_null;
 }
 
+/* CXL labels store UUIDs instead of GUIDs for the same data */
+static const uuid_t *to_abstraction_uuid(enum nvdimm_claim_class claim_class,
+					 uuid_t *target)
+{
+	if (claim_class == NVDIMM_CCLASS_BTT)
+		return &nvdimm_btt_uuid;
+	else if (claim_class == NVDIMM_CCLASS_BTT2)
+		return &nvdimm_btt2_uuid;
+	else if (claim_class == NVDIMM_CCLASS_PFN)
+		return &nvdimm_pfn_uuid;
+	else if (claim_class == NVDIMM_CCLASS_DAX)
+		return &nvdimm_dax_uuid;
+	else if (claim_class == NVDIMM_CCLASS_UNKNOWN) {
+		/*
+		 * If we're modifying a namespace for which we don't
+		 * know the claim_class, don't touch the existing uuid.
+		 */
+		return target;
+	} else
+		return &uuid_null;
+}
+
 static void reap_victim(struct nd_mapping *nd_mapping,
 		struct nd_label_ent *victim)
 {
@@ -775,18 +823,18 @@ static void reap_victim(struct nd_mapping *nd_mapping,
 static void nsl_set_type_guid(struct nvdimm_drvdata *ndd,
 			      struct nd_namespace_label *nd_label, guid_t *guid)
 {
-	if (namespace_label_has(ndd, type_guid))
-		guid_copy(&nd_label->type_guid, guid);
+	if (efi_namespace_label_has(ndd, type_guid))
+		guid_copy(&nd_label->efi.type_guid, guid);
 }
 
 bool nsl_validate_type_guid(struct nvdimm_drvdata *ndd,
 			    struct nd_namespace_label *nd_label, guid_t *guid)
 {
-	if (!namespace_label_has(ndd, type_guid))
+	if (ndd->cxl || !efi_namespace_label_has(ndd, type_guid))
 		return true;
-	if (!guid_equal(&nd_label->type_guid, guid)) {
+	if (!guid_equal(&nd_label->efi.type_guid, guid)) {
 		dev_dbg(ndd->dev, "expect type_guid %pUb got %pUb\n", guid,
-			&nd_label->type_guid);
+			&nd_label->efi.type_guid);
 		return false;
 	}
 	return true;
@@ -796,19 +844,34 @@ static void nsl_set_claim_class(struct nvdimm_drvdata *ndd,
 				struct nd_namespace_label *nd_label,
 				enum nvdimm_claim_class claim_class)
 {
-	if (!namespace_label_has(ndd, abstraction_guid))
+	if (ndd->cxl) {
+		uuid_t uuid;
+
+		import_uuid(&uuid, nd_label->cxl.abstraction_uuid);
+		export_uuid(nd_label->cxl.abstraction_uuid,
+			    to_abstraction_uuid(claim_class, &uuid));
+		return;
+	}
+
+	if (!efi_namespace_label_has(ndd, abstraction_guid))
 		return;
-	guid_copy(&nd_label->abstraction_guid,
+	guid_copy(&nd_label->efi.abstraction_guid,
 		  to_abstraction_guid(claim_class,
-				      &nd_label->abstraction_guid));
+				      &nd_label->efi.abstraction_guid));
 }
 
 enum nvdimm_claim_class nsl_get_claim_class(struct nvdimm_drvdata *ndd,
 					    struct nd_namespace_label *nd_label)
 {
-	if (!namespace_label_has(ndd, abstraction_guid))
+	if (ndd->cxl) {
+		uuid_t uuid;
+
+		import_uuid(&uuid, nd_label->cxl.abstraction_uuid);
+		return uuid_to_nvdimm_cclass(&uuid);
+	}
+	if (!efi_namespace_label_has(ndd, abstraction_guid))
 		return NVDIMM_CCLASS_NONE;
-	return to_nvdimm_cclass(&nd_label->abstraction_guid);
+	return guid_to_nvdimm_cclass(&nd_label->efi.abstraction_guid);
 }
 
 static int __pmem_label_update(struct nd_region *nd_region,
@@ -851,10 +914,11 @@ static int __pmem_label_update(struct nd_region *nd_region,
 
 	nd_label = to_label(ndd, slot);
 	memset(nd_label, 0, sizeof_namespace_label(ndd));
-	memcpy(nd_label->uuid, nspm->uuid, NSLABEL_UUID_LEN);
+	nsl_set_uuid(ndd, nd_label, nspm->uuid);
 	nsl_set_name(ndd, nd_label, nspm->alt_name);
 	nsl_set_flags(ndd, nd_label, flags);
 	nsl_set_nlabel(ndd, nd_label, nd_region->ndr_mappings);
+	nsl_set_nrange(ndd, nd_label, 1);
 	nsl_set_position(ndd, nd_label, pos);
 	nsl_set_isetcookie(ndd, nd_label, cookie);
 	nsl_set_rawsize(ndd, nd_label, resource_size(res));
@@ -878,9 +942,8 @@ static int __pmem_label_update(struct nd_region *nd_region,
 	list_for_each_entry(label_ent, &nd_mapping->labels, list) {
 		if (!label_ent->label)
 			continue;
-		if (test_and_clear_bit(ND_LABEL_REAP, &label_ent->flags)
-				|| memcmp(nspm->uuid, label_ent->label->uuid,
-					NSLABEL_UUID_LEN) == 0)
+		if (test_and_clear_bit(ND_LABEL_REAP, &label_ent->flags) ||
+		    nsl_uuid_equal(ndd, label_ent->label, nspm->uuid))
 			reap_victim(nd_mapping, label_ent);
 	}
 
@@ -941,7 +1004,7 @@ static void nsl_set_blk_isetcookie(struct nvdimm_drvdata *ndd,
 				   struct nd_namespace_label *nd_label,
 				   u64 isetcookie)
 {
-	if (namespace_label_has(ndd, type_guid)) {
+	if (efi_namespace_label_has(ndd, type_guid)) {
 		nsl_set_isetcookie(ndd, nd_label, isetcookie);
 		return;
 	}
@@ -952,7 +1015,7 @@ bool nsl_validate_blk_isetcookie(struct nvdimm_drvdata *ndd,
 				 struct nd_namespace_label *nd_label,
 				 u64 isetcookie)
 {
-	if (!namespace_label_has(ndd, type_guid))
+	if (!efi_namespace_label_has(ndd, type_guid))
 		return true;
 
 	if (nsl_get_isetcookie(ndd, nd_label) != isetcookie) {
@@ -968,7 +1031,7 @@ static void nsl_set_blk_nlabel(struct nvdimm_drvdata *ndd,
 			       struct nd_namespace_label *nd_label, int nlabel,
 			       bool first)
 {
-	if (!namespace_label_has(ndd, type_guid)) {
+	if (!efi_namespace_label_has(ndd, type_guid)) {
 		nsl_set_nlabel(ndd, nd_label, 0); /* N/A */
 		return;
 	}
@@ -979,7 +1042,7 @@ static void nsl_set_blk_position(struct nvdimm_drvdata *ndd,
 				 struct nd_namespace_label *nd_label,
 				 bool first)
 {
-	if (!namespace_label_has(ndd, type_guid)) {
+	if (!efi_namespace_label_has(ndd, type_guid)) {
 		nsl_set_position(ndd, nd_label, 0);
 		return;
 	}
@@ -1005,7 +1068,6 @@ static int __blk_label_update(struct nd_region *nd_region,
 	unsigned long *free, *victim_map = NULL;
 	struct resource *res, **old_res_list;
 	struct nd_label_id label_id;
-	u8 uuid[NSLABEL_UUID_LEN];
 	int min_dpa_idx = 0;
 	LIST_HEAD(list);
 	u32 nslot, slot;
@@ -1043,8 +1105,7 @@ static int __blk_label_update(struct nd_region *nd_region,
 		/* mark unused labels for garbage collection */
 		for_each_clear_bit_le(slot, free, nslot) {
 			nd_label = to_label(ndd, slot);
-			memcpy(uuid, nd_label->uuid, NSLABEL_UUID_LEN);
-			if (memcmp(uuid, nsblk->uuid, NSLABEL_UUID_LEN) != 0)
+			if (!nsl_uuid_equal(ndd, nd_label, nsblk->uuid))
 				continue;
 			res = to_resource(ndd, nd_label);
 			if (res && is_old_resource(res, old_res_list,
@@ -1113,7 +1174,7 @@ static int __blk_label_update(struct nd_region *nd_region,
 
 		nd_label = to_label(ndd, slot);
 		memset(nd_label, 0, sizeof_namespace_label(ndd));
-		memcpy(nd_label->uuid, nsblk->uuid, NSLABEL_UUID_LEN);
+		nsl_set_uuid(ndd, nd_label, nsblk->uuid);
 		nsl_set_name(ndd, nd_label, nsblk->alt_name);
 		nsl_set_flags(ndd, nd_label, NSLABEL_FLAG_LOCAL);
 
@@ -1161,8 +1222,7 @@ static int __blk_label_update(struct nd_region *nd_region,
 		if (!nd_label)
 			continue;
 		nlabel++;
-		memcpy(uuid, nd_label->uuid, NSLABEL_UUID_LEN);
-		if (memcmp(uuid, nsblk->uuid, NSLABEL_UUID_LEN) != 0)
+		if (!nsl_uuid_equal(ndd, nd_label, nsblk->uuid))
 			continue;
 		nlabel--;
 		list_move(&label_ent->list, &list);
@@ -1192,8 +1252,7 @@ static int __blk_label_update(struct nd_region *nd_region,
 	}
 	for_each_clear_bit_le(slot, free, nslot) {
 		nd_label = to_label(ndd, slot);
-		memcpy(uuid, nd_label->uuid, NSLABEL_UUID_LEN);
-		if (memcmp(uuid, nsblk->uuid, NSLABEL_UUID_LEN) != 0)
+		if (!nsl_uuid_equal(ndd, nd_label, nsblk->uuid))
 			continue;
 		res = to_resource(ndd, nd_label);
 		res->flags &= ~DPA_RESOURCE_ADJUSTED;
@@ -1273,12 +1332,11 @@ static int init_labels(struct nd_mapping *nd_mapping, int num_labels)
 	return max(num_labels, old_num_labels);
 }
 
-static int del_labels(struct nd_mapping *nd_mapping, u8 *uuid)
+static int del_labels(struct nd_mapping *nd_mapping, uuid_t *uuid)
 {
 	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
 	struct nd_label_ent *label_ent, *e;
 	struct nd_namespace_index *nsindex;
-	u8 label_uuid[NSLABEL_UUID_LEN];
 	unsigned long *free;
 	LIST_HEAD(list);
 	u32 nslot, slot;
@@ -1298,8 +1356,7 @@ static int del_labels(struct nd_mapping *nd_mapping, u8 *uuid)
 		if (!nd_label)
 			continue;
 		active++;
-		memcpy(label_uuid, nd_label->uuid, NSLABEL_UUID_LEN);
-		if (memcmp(label_uuid, uuid, NSLABEL_UUID_LEN) != 0)
+		if (!nsl_uuid_equal(ndd, nd_label, uuid))
 			continue;
 		active--;
 		slot = to_slot(ndd, nd_label);
@@ -1395,5 +1452,13 @@ int __init nd_label_init(void)
 	WARN_ON(guid_parse(NVDIMM_PFN_GUID, &nvdimm_pfn_guid));
 	WARN_ON(guid_parse(NVDIMM_DAX_GUID, &nvdimm_dax_guid));
 
+	WARN_ON(uuid_parse(NVDIMM_BTT_GUID, &nvdimm_btt_uuid));
+	WARN_ON(uuid_parse(NVDIMM_BTT2_GUID, &nvdimm_btt2_uuid));
+	WARN_ON(uuid_parse(NVDIMM_PFN_GUID, &nvdimm_pfn_uuid));
+	WARN_ON(uuid_parse(NVDIMM_DAX_GUID, &nvdimm_dax_uuid));
+
+	WARN_ON(uuid_parse(CXL_REGION_UUID, &cxl_region_uuid));
+	WARN_ON(uuid_parse(CXL_NAMESPACE_UUID, &cxl_namespace_uuid));
+
 	return 0;
 }
diff --git a/drivers/nvdimm/label.h b/drivers/nvdimm/label.h
index 31f94fad7b92..8ee248fc214f 100644
--- a/drivers/nvdimm/label.h
+++ b/drivers/nvdimm/label.h
@@ -34,6 +34,7 @@ enum {
  * struct nd_namespace_index - label set superblock
  * @sig: NAMESPACE_INDEX\0
  * @flags: placeholder
+ * @labelsize: log2 size (v1 labels 128 bytes v2 labels 256 bytes)
  * @seq: sequence number for this index
  * @myoff: offset of this index in label area
  * @mysize: size of this index struct
@@ -43,7 +44,7 @@ enum {
  * @major: label area major version
  * @minor: label area minor version
  * @checksum: fletcher64 of all fields
- * @free[0]: bitmap, nlabel bits
+ * @free: bitmap, nlabel bits
  *
  * The size of free[] is rounded up so the total struct size is a
  * multiple of NSINDEX_ALIGN bytes.  Any bits this allocates beyond
@@ -66,7 +67,39 @@ struct nd_namespace_index {
 };
 
 /**
- * struct nd_namespace_label - namespace superblock
+ * struct cxl_region_label - CXL 2.0 Table 211
+ * @type: uuid identifying this label format (region)
+ * @uuid: uuid for the region this label describes
+ * @flags: NSLABEL_FLAG_UPDATING (all other flags reserved)
+ * @nlabel: 1 per interleave-way in the region
+ * @position: this label's position in the set
+ * @dpa: start address in device-local capacity for this label
+ * @rawsize: size of this label's contribution to region
+ * @hpa: mandatory system physical address to map this region
+ * @slot: slot id of this label in label area
+ * @ig: interleave granularity (1 << @ig) * 256 bytes
+ * @align: alignment in SZ_256M blocks
+ * @reserved: reserved
+ * @checksum: fletcher64 sum of this label
+ */
+struct cxl_region_label {
+	u8 type[NSLABEL_UUID_LEN];
+	u8 uuid[NSLABEL_UUID_LEN];
+	__le32 flags;
+	__le16 nlabel;
+	__le16 position;
+	__le64 dpa;
+	__le64 rawsize;
+	__le64 hpa;
+	__le32 slot;
+	__le32 ig;
+	__le32 align;
+	u8 reserved[0xac];
+	__le64 checksum;
+};
+
+/**
+ * struct nvdimm_efi_label - namespace superblock
  * @uuid: UUID per RFC 4122
  * @name: optional name (NULL-terminated)
  * @flags: see NSLABEL_FLAG_*
@@ -77,9 +110,14 @@ struct nd_namespace_index {
  * @dpa: DPA of NVM range on this DIMM
  * @rawsize: size of namespace
  * @slot: slot of this label in label area
- * @unused: must be zero
+ * @align: physical address alignment of the namespace
+ * @reserved: reserved
+ * @type_guid: copy of struct acpi_nfit_system_address.range_guid
+ * @abstraction_guid: personality id (btt, btt2, fsdax, devdax....)
+ * @reserved2: reserved
+ * @checksum: fletcher64 sum of this object
  */
-struct nd_namespace_label {
+struct nvdimm_efi_label {
 	u8 uuid[NSLABEL_UUID_LEN];
 	u8 name[NSLABEL_NAME_LEN];
 	__le32 flags;
@@ -92,7 +130,7 @@ struct nd_namespace_label {
 	__le32 slot;
 	/*
 	 * Accessing fields past this point should be gated by a
-	 * namespace_label_has() check.
+	 * efi_namespace_label_has() check.
 	 */
 	u8 align;
 	u8 reserved[3];
@@ -102,11 +140,57 @@ struct nd_namespace_label {
 	__le64 checksum;
 };
 
+/**
+ * struct nvdimm_cxl_label - CXL 2.0 Table 212
+ * @type: uuid identifying this label format (namespace)
+ * @uuid: uuid for the namespace this label describes
+ * @name: friendly name for the namespace
+ * @flags: NSLABEL_FLAG_UPDATING (all other flags reserved)
+ * @nrange: discontiguous namespace support
+ * @position: this label's position in the set
+ * @dpa: start address in device-local capacity for this label
+ * @rawsize: size of this label's contribution to namespace
+ * @slot: slot id of this label in label area
+ * @align: alignment in SZ_256M blocks
+ * @region_uuid: host interleave set identifier
+ * @abstraction_uuid: personality driver for this namespace
+ * @lbasize: address geometry for disk-like personalities
+ * @reserved: reserved
+ * @checksum: fletcher64 sum of this label
+ */
+struct nvdimm_cxl_label {
+	u8 type[NSLABEL_UUID_LEN];
+	u8 uuid[NSLABEL_UUID_LEN];
+	u8 name[NSLABEL_NAME_LEN];
+	__le32 flags;
+	__le16 nrange;
+	__le16 position;
+	__le64 dpa;
+	__le64 rawsize;
+	__le32 slot;
+	__le32 align;
+	u8 region_uuid[16];
+	u8 abstraction_uuid[16];
+	__le16 lbasize;
+	u8 reserved[0x56];
+	__le64 checksum;
+};
+
+struct nd_namespace_label {
+	union {
+		struct nvdimm_cxl_label cxl;
+		struct nvdimm_efi_label efi;
+	};
+};
+
 #define NVDIMM_BTT_GUID "8aed63a2-29a2-4c66-8b12-f05d15d3922a"
 #define NVDIMM_BTT2_GUID "18633bfc-1735-4217-8ac9-17239282d3f8"
 #define NVDIMM_PFN_GUID "266400ba-fb9f-4677-bcb0-968f11d0d225"
 #define NVDIMM_DAX_GUID "97a86d9c-3cdd-4eda-986f-5068b4f80088"
 
+#define CXL_REGION_UUID "529d7c61-da07-47c4-a93f-ecdf2c06f444"
+#define CXL_NAMESPACE_UUID "68bb2c0a-5a77-4937-9f85-3caf41a0f93c"
+
 /**
  * struct nd_label_id - identifier string for dpa allocation
  * @id: "{blk|pmem}-<namespace uuid>"
diff --git a/drivers/nvdimm/namespace_devs.c b/drivers/nvdimm/namespace_devs.c
index 4cec171c934d..b57a2d36c517 100644
--- a/drivers/nvdimm/namespace_devs.c
+++ b/drivers/nvdimm/namespace_devs.c
@@ -51,7 +51,7 @@ static bool is_namespace_io(const struct device *dev);
 
 static int is_uuid_busy(struct device *dev, void *data)
 {
-	u8 *uuid1 = data, *uuid2 = NULL;
+	uuid_t *uuid1 = data, *uuid2 = NULL;
 
 	if (is_namespace_pmem(dev)) {
 		struct nd_namespace_pmem *nspm = to_nd_namespace_pmem(dev);
@@ -71,7 +71,7 @@ static int is_uuid_busy(struct device *dev, void *data)
 		uuid2 = nd_pfn->uuid;
 	}
 
-	if (uuid2 && memcmp(uuid1, uuid2, NSLABEL_UUID_LEN) == 0)
+	if (uuid2 && uuid_equal(uuid1, uuid2))
 		return -EBUSY;
 
 	return 0;
@@ -89,7 +89,7 @@ static int is_namespace_uuid_busy(struct device *dev, void *data)
  * @dev: any device on a nvdimm_bus
  * @uuid: uuid to check
  */
-bool nd_is_uuid_unique(struct device *dev, u8 *uuid)
+bool nd_is_uuid_unique(struct device *dev, uuid_t *uuid)
 {
 	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
 
@@ -192,12 +192,10 @@ const char *nvdimm_namespace_disk_name(struct nd_namespace_common *ndns,
 }
 EXPORT_SYMBOL(nvdimm_namespace_disk_name);
 
-const u8 *nd_dev_to_uuid(struct device *dev)
+const uuid_t *nd_dev_to_uuid(struct device *dev)
 {
-	static const u8 null_uuid[16];
-
 	if (!dev)
-		return null_uuid;
+		return &uuid_null;
 
 	if (is_namespace_pmem(dev)) {
 		struct nd_namespace_pmem *nspm = to_nd_namespace_pmem(dev);
@@ -208,7 +206,7 @@ const u8 *nd_dev_to_uuid(struct device *dev)
 
 		return nsblk->uuid;
 	} else
-		return null_uuid;
+		return &uuid_null;
 }
 EXPORT_SYMBOL(nd_dev_to_uuid);
 
@@ -938,7 +936,8 @@ static void nd_namespace_pmem_set_resource(struct nd_region *nd_region,
 	res->end = res->start + size - 1;
 }
 
-static bool uuid_not_set(const u8 *uuid, struct device *dev, const char *where)
+static bool uuid_not_set(const uuid_t *uuid, struct device *dev,
+			 const char *where)
 {
 	if (!uuid) {
 		dev_dbg(dev, "%s: uuid not set\n", where);
@@ -957,7 +956,7 @@ static ssize_t __size_store(struct device *dev, unsigned long long val)
 	struct nd_label_id label_id;
 	u32 flags = 0, remainder;
 	int rc, i, id = -1;
-	u8 *uuid = NULL;
+	uuid_t *uuid = NULL;
 
 	if (dev->driver || ndns->claim)
 		return -EBUSY;
@@ -1050,7 +1049,7 @@ static ssize_t size_store(struct device *dev,
 {
 	struct nd_region *nd_region = to_nd_region(dev->parent);
 	unsigned long long val;
-	u8 **uuid = NULL;
+	uuid_t **uuid = NULL;
 	int rc;
 
 	rc = kstrtoull(buf, 0, &val);
@@ -1147,7 +1146,7 @@ static ssize_t size_show(struct device *dev,
 }
 static DEVICE_ATTR(size, 0444, size_show, size_store);
 
-static u8 *namespace_to_uuid(struct device *dev)
+static uuid_t *namespace_to_uuid(struct device *dev)
 {
 	if (is_namespace_pmem(dev)) {
 		struct nd_namespace_pmem *nspm = to_nd_namespace_pmem(dev);
@@ -1161,10 +1160,10 @@ static u8 *namespace_to_uuid(struct device *dev)
 		return ERR_PTR(-ENXIO);
 }
 
-static ssize_t uuid_show(struct device *dev,
-		struct device_attribute *attr, char *buf)
+static ssize_t uuid_show(struct device *dev, struct device_attribute *attr,
+			 char *buf)
 {
-	u8 *uuid = namespace_to_uuid(dev);
+	uuid_t *uuid = namespace_to_uuid(dev);
 
 	if (IS_ERR(uuid))
 		return PTR_ERR(uuid);
@@ -1181,7 +1180,8 @@ static ssize_t uuid_show(struct device *dev,
  * @old_uuid: reference to the uuid storage location in the namespace object
  */
 static int namespace_update_uuid(struct nd_region *nd_region,
-		struct device *dev, u8 *new_uuid, u8 **old_uuid)
+				 struct device *dev, uuid_t *new_uuid,
+				 uuid_t **old_uuid)
 {
 	u32 flags = is_namespace_blk(dev) ? NSLABEL_FLAG_LOCAL : 0;
 	struct nd_label_id old_label_id;
@@ -1231,10 +1231,12 @@ static int namespace_update_uuid(struct nd_region *nd_region,
 		list_for_each_entry(label_ent, &nd_mapping->labels, list) {
 			struct nd_namespace_label *nd_label = label_ent->label;
 			struct nd_label_id label_id;
+			uuid_t uuid;
 
 			if (!nd_label)
 				continue;
-			nd_label_gen_id(&label_id, nd_label->uuid,
+			nsl_get_uuid(ndd, nd_label, &uuid);
+			nd_label_gen_id(&label_id, &uuid,
 					nsl_get_flags(ndd, nd_label));
 			if (strcmp(old_label_id.id, label_id.id) == 0)
 				set_bit(ND_LABEL_REAP, &label_ent->flags);
@@ -1251,9 +1253,9 @@ static ssize_t uuid_store(struct device *dev,
 		struct device_attribute *attr, const char *buf, size_t len)
 {
 	struct nd_region *nd_region = to_nd_region(dev->parent);
-	u8 *uuid = NULL;
+	uuid_t *uuid = NULL;
+	uuid_t **ns_uuid;
 	ssize_t rc = 0;
-	u8 **ns_uuid;
 
 	if (is_namespace_pmem(dev)) {
 		struct nd_namespace_pmem *nspm = to_nd_namespace_pmem(dev);
@@ -1378,8 +1380,8 @@ static ssize_t dpa_extents_show(struct device *dev,
 {
 	struct nd_region *nd_region = to_nd_region(dev->parent);
 	struct nd_label_id label_id;
+	uuid_t *uuid = NULL;
 	int count = 0, i;
-	u8 *uuid = NULL;
 	u32 flags = 0;
 
 	nvdimm_bus_lock(dev);
@@ -1831,8 +1833,8 @@ static struct device **create_namespace_io(struct nd_region *nd_region)
 	return devs;
 }
 
-static bool has_uuid_at_pos(struct nd_region *nd_region, u8 *uuid,
-		u64 cookie, u16 pos)
+static bool has_uuid_at_pos(struct nd_region *nd_region, const uuid_t *uuid,
+			    u64 cookie, u16 pos)
 {
 	struct nd_namespace_label *found = NULL;
 	int i;
@@ -1846,17 +1848,16 @@ static bool has_uuid_at_pos(struct nd_region *nd_region, u8 *uuid,
 
 		list_for_each_entry(label_ent, &nd_mapping->labels, list) {
 			struct nd_namespace_label *nd_label = label_ent->label;
-			u16 position, nlabel;
+			u16 position;
 
 			if (!nd_label)
 				continue;
 			position = nsl_get_position(ndd, nd_label);
-			nlabel = nsl_get_nlabel(ndd, nd_label);
 
 			if (!nsl_validate_isetcookie(ndd, nd_label, cookie))
 				continue;
 
-			if (memcmp(nd_label->uuid, uuid, NSLABEL_UUID_LEN) != 0)
+			if (!nsl_uuid_equal(ndd, nd_label, uuid))
 				continue;
 
 			if (!nsl_validate_type_guid(ndd, nd_label,
@@ -1868,7 +1869,7 @@ static bool has_uuid_at_pos(struct nd_region *nd_region, u8 *uuid,
 				return false;
 			}
 			found_uuid = true;
-			if (nlabel != nd_region->ndr_mappings)
+			if (!nsl_validate_nlabel(nd_region, ndd, nd_label))
 				continue;
 			if (position != pos)
 				continue;
@@ -1881,7 +1882,7 @@ static bool has_uuid_at_pos(struct nd_region *nd_region, u8 *uuid,
 	return found != NULL;
 }
 
-static int select_pmem_id(struct nd_region *nd_region, u8 *pmem_id)
+static int select_pmem_id(struct nd_region *nd_region, const uuid_t *pmem_id)
 {
 	int i;
 
@@ -1900,7 +1901,7 @@ static int select_pmem_id(struct nd_region *nd_region, u8 *pmem_id)
 			nd_label = label_ent->label;
 			if (!nd_label)
 				continue;
-			if (memcmp(nd_label->uuid, pmem_id, NSLABEL_UUID_LEN) == 0)
+			if (nsl_uuid_equal(ndd, nd_label, pmem_id))
 				break;
 			nd_label = NULL;
 		}
@@ -1923,7 +1924,8 @@ static int select_pmem_id(struct nd_region *nd_region, u8 *pmem_id)
 			/* pass */;
 		else {
 			dev_dbg(&nd_region->dev, "%s invalid label for %pUb\n",
-					dev_name(ndd->dev), nd_label->uuid);
+				dev_name(ndd->dev),
+				nsl_uuid_raw(ndd, nd_label));
 			return -EINVAL;
 		}
 
@@ -1953,6 +1955,7 @@ static struct device *create_namespace_pmem(struct nd_region *nd_region,
 	resource_size_t size = 0;
 	struct resource *res;
 	struct device *dev;
+	uuid_t uuid;
 	int rc = 0;
 	u16 i;
 
@@ -1963,12 +1966,12 @@ static struct device *create_namespace_pmem(struct nd_region *nd_region,
 
 	if (!nsl_validate_isetcookie(ndd, nd_label, cookie)) {
 		dev_dbg(&nd_region->dev, "invalid cookie in label: %pUb\n",
-				nd_label->uuid);
+			nsl_uuid_raw(ndd, nd_label));
 		if (!nsl_validate_isetcookie(ndd, nd_label, altcookie))
 			return ERR_PTR(-EAGAIN);
 
 		dev_dbg(&nd_region->dev, "valid altcookie in label: %pUb\n",
-				nd_label->uuid);
+			nsl_uuid_raw(ndd, nd_label));
 	}
 
 	nspm = kzalloc(sizeof(*nspm), GFP_KERNEL);
@@ -1984,9 +1987,12 @@ static struct device *create_namespace_pmem(struct nd_region *nd_region,
 	res->flags = IORESOURCE_MEM;
 
 	for (i = 0; i < nd_region->ndr_mappings; i++) {
-		if (has_uuid_at_pos(nd_region, nd_label->uuid, cookie, i))
+		uuid_t uuid;
+
+		nsl_get_uuid(ndd, nd_label, &uuid);
+		if (has_uuid_at_pos(nd_region, &uuid, cookie, i))
 			continue;
-		if (has_uuid_at_pos(nd_region, nd_label->uuid, altcookie, i))
+		if (has_uuid_at_pos(nd_region, &uuid, altcookie, i))
 			continue;
 		break;
 	}
@@ -2000,7 +2006,7 @@ static struct device *create_namespace_pmem(struct nd_region *nd_region,
 		 * find a dimm with two instances of the same uuid.
 		 */
 		dev_err(&nd_region->dev, "%s missing label for %pUb\n",
-				nvdimm_name(nvdimm), nd_label->uuid);
+			nvdimm_name(nvdimm), nsl_uuid_raw(ndd, nd_label));
 		rc = -EINVAL;
 		goto err;
 	}
@@ -2013,7 +2019,8 @@ static struct device *create_namespace_pmem(struct nd_region *nd_region,
 	 * the dimm being enabled (i.e. nd_label_reserve_dpa()
 	 * succeeded).
 	 */
-	rc = select_pmem_id(nd_region, nd_label->uuid);
+	nsl_get_uuid(ndd, nd_label, &uuid);
+	rc = select_pmem_id(nd_region, &uuid);
 	if (rc)
 		goto err;
 
@@ -2039,8 +2046,8 @@ static struct device *create_namespace_pmem(struct nd_region *nd_region,
 		WARN_ON(nspm->alt_name || nspm->uuid);
 		nspm->alt_name = kmemdup(nsl_ref_name(ndd, label0),
 					 NSLABEL_NAME_LEN, GFP_KERNEL);
-		nspm->uuid = kmemdup((void __force *) label0->uuid,
-				NSLABEL_UUID_LEN, GFP_KERNEL);
+		nsl_get_uuid(ndd, label0, &uuid);
+		nspm->uuid = kmemdup(&uuid, sizeof(uuid_t), GFP_KERNEL);
 		nspm->lbasize = nsl_get_lbasize(ndd, label0);
 		nspm->nsio.common.claim_class =
 			nsl_get_claim_class(ndd, label0);
@@ -2217,15 +2224,15 @@ static int add_namespace_resource(struct nd_region *nd_region,
 	int i;
 
 	for (i = 0; i < count; i++) {
-		u8 *uuid = namespace_to_uuid(devs[i]);
+		uuid_t *uuid = namespace_to_uuid(devs[i]);
 		struct resource *res;
 
-		if (IS_ERR_OR_NULL(uuid)) {
+		if (IS_ERR(uuid)) {
 			WARN_ON(1);
 			continue;
 		}
 
-		if (memcmp(uuid, nd_label->uuid, NSLABEL_UUID_LEN) != 0)
+		if (!nsl_uuid_equal(ndd, nd_label, uuid))
 			continue;
 		if (is_namespace_blk(devs[i])) {
 			res = nsblk_add_resource(nd_region, ndd,
@@ -2236,8 +2243,8 @@ static int add_namespace_resource(struct nd_region *nd_region,
 			nd_dbg_dpa(nd_region, ndd, res, "%d assign\n", count);
 		} else {
 			dev_err(&nd_region->dev,
-					"error: conflicting extents for uuid: %pUb\n",
-					nd_label->uuid);
+				"error: conflicting extents for uuid: %pUb\n",
+				uuid);
 			return -ENXIO;
 		}
 		break;
@@ -2257,6 +2264,7 @@ static struct device *create_namespace_blk(struct nd_region *nd_region,
 	char name[NSLABEL_NAME_LEN];
 	struct device *dev = NULL;
 	struct resource *res;
+	uuid_t uuid;
 
 	if (!nsl_validate_type_guid(ndd, nd_label, &nd_set->type_guid))
 		return ERR_PTR(-EAGAIN);
@@ -2271,7 +2279,8 @@ static struct device *create_namespace_blk(struct nd_region *nd_region,
 	dev->parent = &nd_region->dev;
 	nsblk->id = -1;
 	nsblk->lbasize = nsl_get_lbasize(ndd, nd_label);
-	nsblk->uuid = kmemdup(nd_label->uuid, NSLABEL_UUID_LEN, GFP_KERNEL);
+	nsl_get_uuid(ndd, nd_label, &uuid);
+	nsblk->uuid = kmemdup(&uuid, sizeof(uuid_t), GFP_KERNEL);
 	nsblk->common.claim_class = nsl_get_claim_class(ndd, nd_label);
 	if (!nsblk->uuid)
 		goto blk_err;
diff --git a/drivers/nvdimm/nd-core.h b/drivers/nvdimm/nd-core.h
index 564faa36a3ca..a11850dd475d 100644
--- a/drivers/nvdimm/nd-core.h
+++ b/drivers/nvdimm/nd-core.h
@@ -126,8 +126,9 @@ void nvdimm_bus_destroy_ndctl(struct nvdimm_bus *nvdimm_bus);
 void nd_synchronize(void);
 void __nd_device_register(struct device *dev);
 struct nd_label_id;
-char *nd_label_gen_id(struct nd_label_id *label_id, u8 *uuid, u32 flags);
-bool nd_is_uuid_unique(struct device *dev, u8 *uuid);
+char *nd_label_gen_id(struct nd_label_id *label_id, const uuid_t *uuid,
+		      u32 flags);
+bool nd_is_uuid_unique(struct device *dev, uuid_t *uuid);
 struct nd_region;
 struct nvdimm_drvdata;
 struct nd_mapping;
diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h
index 5467ebbb4a6b..6f8ce114032d 100644
--- a/drivers/nvdimm/nd.h
+++ b/drivers/nvdimm/nd.h
@@ -30,6 +30,7 @@ struct nvdimm_drvdata {
 	int nslabel_size;
 	struct nd_cmd_get_config_size nsarea;
 	void *data;
+	bool cxl;
 	int ns_current, ns_next;
 	struct resource dpa;
 	struct kref kref;
@@ -38,13 +39,17 @@ struct nvdimm_drvdata {
 static inline const u8 *nsl_ref_name(struct nvdimm_drvdata *ndd,
 				     struct nd_namespace_label *nd_label)
 {
-	return nd_label->name;
+	if (ndd->cxl)
+		return nd_label->cxl.name;
+	return nd_label->efi.name;
 }
 
 static inline u8 *nsl_get_name(struct nvdimm_drvdata *ndd,
 			       struct nd_namespace_label *nd_label, u8 *name)
 {
-	return memcpy(name, nd_label->name, NSLABEL_NAME_LEN);
+	if (ndd->cxl)
+		return memcpy(name, nd_label->cxl.name, NSLABEL_NAME_LEN);
+	return memcpy(name, nd_label->efi.name, NSLABEL_NAME_LEN);
 }
 
 static inline u8 *nsl_set_name(struct nvdimm_drvdata *ndd,
@@ -52,129 +57,242 @@ static inline u8 *nsl_set_name(struct nvdimm_drvdata *ndd,
 {
 	if (!name)
 		return NULL;
-	return memcpy(nd_label->name, name, NSLABEL_NAME_LEN);
+	if (ndd->cxl)
+		return memcpy(nd_label->cxl.name, name, NSLABEL_NAME_LEN);
+	return memcpy(nd_label->efi.name, name, NSLABEL_NAME_LEN);
 }
 
 static inline u32 nsl_get_slot(struct nvdimm_drvdata *ndd,
 			       struct nd_namespace_label *nd_label)
 {
-	return __le32_to_cpu(nd_label->slot);
+	if (ndd->cxl)
+		return __le32_to_cpu(nd_label->cxl.slot);
+	return __le32_to_cpu(nd_label->efi.slot);
 }
 
 static inline void nsl_set_slot(struct nvdimm_drvdata *ndd,
 				struct nd_namespace_label *nd_label, u32 slot)
 {
-	nd_label->slot = __cpu_to_le32(slot);
+	if (ndd->cxl)
+		nd_label->cxl.slot = __cpu_to_le32(slot);
+	else
+		nd_label->efi.slot = __cpu_to_le32(slot);
 }
 
 static inline u64 nsl_get_checksum(struct nvdimm_drvdata *ndd,
 				   struct nd_namespace_label *nd_label)
 {
-	return __le64_to_cpu(nd_label->checksum);
+	if (ndd->cxl)
+		return __le64_to_cpu(nd_label->cxl.checksum);
+	return __le64_to_cpu(nd_label->efi.checksum);
 }
 
 static inline void nsl_set_checksum(struct nvdimm_drvdata *ndd,
 				    struct nd_namespace_label *nd_label,
 				    u64 checksum)
 {
-	nd_label->checksum = __cpu_to_le64(checksum);
+	if (ndd->cxl)
+		nd_label->cxl.checksum = __cpu_to_le64(checksum);
+	else
+		nd_label->efi.checksum = __cpu_to_le64(checksum);
 }
 
 static inline u32 nsl_get_flags(struct nvdimm_drvdata *ndd,
 				struct nd_namespace_label *nd_label)
 {
-	return __le32_to_cpu(nd_label->flags);
+	if (ndd->cxl)
+		return __le32_to_cpu(nd_label->cxl.flags);
+	return __le32_to_cpu(nd_label->efi.flags);
 }
 
 static inline void nsl_set_flags(struct nvdimm_drvdata *ndd,
 				 struct nd_namespace_label *nd_label, u32 flags)
 {
-	nd_label->flags = __cpu_to_le32(flags);
+	if (ndd->cxl)
+		nd_label->cxl.flags = __cpu_to_le32(flags);
+	else
+		nd_label->efi.flags = __cpu_to_le32(flags);
 }
 
 static inline u64 nsl_get_dpa(struct nvdimm_drvdata *ndd,
 			      struct nd_namespace_label *nd_label)
 {
-	return __le64_to_cpu(nd_label->dpa);
+	if (ndd->cxl)
+		return __le64_to_cpu(nd_label->cxl.dpa);
+	return __le64_to_cpu(nd_label->efi.dpa);
 }
 
 static inline void nsl_set_dpa(struct nvdimm_drvdata *ndd,
 			       struct nd_namespace_label *nd_label, u64 dpa)
 {
-	nd_label->dpa = __cpu_to_le64(dpa);
+	if (ndd->cxl)
+		nd_label->cxl.dpa = __cpu_to_le64(dpa);
+	else
+		nd_label->efi.dpa = __cpu_to_le64(dpa);
 }
 
 static inline u64 nsl_get_rawsize(struct nvdimm_drvdata *ndd,
 				  struct nd_namespace_label *nd_label)
 {
-	return __le64_to_cpu(nd_label->rawsize);
+	if (ndd->cxl)
+		return __le64_to_cpu(nd_label->cxl.rawsize);
+	return __le64_to_cpu(nd_label->efi.rawsize);
 }
 
 static inline void nsl_set_rawsize(struct nvdimm_drvdata *ndd,
 				   struct nd_namespace_label *nd_label,
 				   u64 rawsize)
 {
-	nd_label->rawsize = __cpu_to_le64(rawsize);
+	if (ndd->cxl)
+		nd_label->cxl.rawsize = __cpu_to_le64(rawsize);
+	else
+		nd_label->efi.rawsize = __cpu_to_le64(rawsize);
 }
 
 static inline u64 nsl_get_isetcookie(struct nvdimm_drvdata *ndd,
 				     struct nd_namespace_label *nd_label)
 {
-	return __le64_to_cpu(nd_label->isetcookie);
+	/* WARN future refactor attempts that break this assumption */
+	if (dev_WARN_ONCE(ndd->dev, ndd->cxl,
+			  "CXL labels do not use the isetcookie concept\n"))
+		return 0;
+	return __le64_to_cpu(nd_label->efi.isetcookie);
 }
 
 static inline void nsl_set_isetcookie(struct nvdimm_drvdata *ndd,
 				      struct nd_namespace_label *nd_label,
 				      u64 isetcookie)
 {
-	nd_label->isetcookie = __cpu_to_le64(isetcookie);
+	if (!ndd->cxl)
+		nd_label->efi.isetcookie = __cpu_to_le64(isetcookie);
 }
 
 static inline bool nsl_validate_isetcookie(struct nvdimm_drvdata *ndd,
 					   struct nd_namespace_label *nd_label,
 					   u64 cookie)
 {
-	return cookie == __le64_to_cpu(nd_label->isetcookie);
+	/*
+	 * Let the EFI and CXL validation comingle, where fields that
+	 * don't matter to CXL always validate.
+	 */
+	if (ndd->cxl)
+		return true;
+	return cookie == __le64_to_cpu(nd_label->efi.isetcookie);
 }
 
 static inline u16 nsl_get_position(struct nvdimm_drvdata *ndd,
 				   struct nd_namespace_label *nd_label)
 {
-	return __le16_to_cpu(nd_label->position);
+	if (ndd->cxl)
+		return __le16_to_cpu(nd_label->cxl.position);
+	return __le16_to_cpu(nd_label->efi.position);
 }
 
 static inline void nsl_set_position(struct nvdimm_drvdata *ndd,
 				    struct nd_namespace_label *nd_label,
 				    u16 position)
 {
-	nd_label->position = __cpu_to_le16(position);
+	if (ndd->cxl)
+		nd_label->cxl.position = __cpu_to_le16(position);
+	else
+		nd_label->efi.position = __cpu_to_le16(position);
 }
 
-
 static inline u16 nsl_get_nlabel(struct nvdimm_drvdata *ndd,
 				 struct nd_namespace_label *nd_label)
 {
-	return __le16_to_cpu(nd_label->nlabel);
+	if (ndd->cxl)
+		return 0;
+	return __le16_to_cpu(nd_label->efi.nlabel);
 }
 
 static inline void nsl_set_nlabel(struct nvdimm_drvdata *ndd,
 				  struct nd_namespace_label *nd_label,
 				  u16 nlabel)
 {
-	nd_label->nlabel = __cpu_to_le16(nlabel);
+	if (!ndd->cxl)
+		nd_label->efi.nlabel = __cpu_to_le16(nlabel);
+}
+
+static inline u16 nsl_get_nrange(struct nvdimm_drvdata *ndd,
+				 struct nd_namespace_label *nd_label)
+{
+	if (ndd->cxl)
+		return __le16_to_cpu(nd_label->cxl.nrange);
+	return 1;
+}
+
+static inline void nsl_set_nrange(struct nvdimm_drvdata *ndd,
+				  struct nd_namespace_label *nd_label,
+				  u16 nrange)
+{
+	if (ndd->cxl)
+		nd_label->cxl.nrange = __cpu_to_le16(nrange);
 }
 
 static inline u64 nsl_get_lbasize(struct nvdimm_drvdata *ndd,
 				  struct nd_namespace_label *nd_label)
 {
-	return __le64_to_cpu(nd_label->lbasize);
+	/*
+	 * Yes, for some reason the EFI labels convey a massive 64-bit
+	 * lbasize, that got fixed for CXL.
+	 */
+	if (ndd->cxl)
+		return __le16_to_cpu(nd_label->cxl.lbasize);
+	return __le64_to_cpu(nd_label->efi.lbasize);
 }
 
 static inline void nsl_set_lbasize(struct nvdimm_drvdata *ndd,
 				   struct nd_namespace_label *nd_label,
 				   u64 lbasize)
 {
-	nd_label->lbasize = __cpu_to_le64(lbasize);
+	if (ndd->cxl)
+		nd_label->cxl.lbasize = __cpu_to_le16(lbasize);
+	else
+		nd_label->efi.lbasize = __cpu_to_le64(lbasize);
+}
+
+static inline const uuid_t *nsl_get_uuid(struct nvdimm_drvdata *ndd,
+					 struct nd_namespace_label *nd_label,
+					 uuid_t *uuid)
+{
+	if (ndd->cxl)
+		import_uuid(uuid, nd_label->cxl.uuid);
+	else
+		import_uuid(uuid, nd_label->efi.uuid);
+	return uuid;
+}
+
+static inline const uuid_t *nsl_set_uuid(struct nvdimm_drvdata *ndd,
+					 struct nd_namespace_label *nd_label,
+					 const uuid_t *uuid)
+{
+	if (ndd->cxl)
+		export_uuid(nd_label->cxl.uuid, uuid);
+	else
+		export_uuid(nd_label->efi.uuid, uuid);
+	return uuid;
+}
+
+static inline bool nsl_uuid_equal(struct nvdimm_drvdata *ndd,
+				  struct nd_namespace_label *nd_label,
+				  const uuid_t *uuid)
+{
+	uuid_t tmp;
+
+	if (ndd->cxl)
+		import_uuid(&tmp, nd_label->cxl.uuid);
+	else
+		import_uuid(&tmp, nd_label->efi.uuid);
+	return uuid_equal(&tmp, uuid);
+}
+
+static inline const u8 *nsl_uuid_raw(struct nvdimm_drvdata *ndd,
+				     struct nd_namespace_label *nd_label)
+{
+	if (ndd->cxl)
+		return nd_label->cxl.uuid;
+	return nd_label->efi.uuid;
 }
 
 bool nsl_validate_blk_isetcookie(struct nvdimm_drvdata *ndd,
@@ -233,8 +351,8 @@ static inline struct nd_namespace_index *to_next_namespace_index(
 
 unsigned sizeof_namespace_label(struct nvdimm_drvdata *ndd);
 
-#define namespace_label_has(ndd, field) \
-	(offsetof(struct nd_namespace_label, field) \
+#define efi_namespace_label_has(ndd, field) \
+	(!ndd->cxl && offsetof(struct nvdimm_efi_label, field) \
 		< sizeof_namespace_label(ndd))
 
 #define nd_dbg_dpa(r, d, res, fmt, arg...) \
@@ -310,6 +428,15 @@ struct nd_region {
 	struct nd_mapping mapping[];
 };
 
+static inline bool nsl_validate_nlabel(struct nd_region *nd_region,
+				       struct nvdimm_drvdata *ndd,
+				       struct nd_namespace_label *nd_label)
+{
+	if (ndd->cxl)
+		return true;
+	return nsl_get_nlabel(ndd, nd_label) == nd_region->ndr_mappings;
+}
+
 struct nd_blk_region {
 	int (*enable)(struct nvdimm_bus *nvdimm_bus, struct device *dev);
 	int (*do_io)(struct nd_blk_region *ndbr, resource_size_t dpa,
@@ -335,7 +462,7 @@ struct nd_btt {
 	struct btt *btt;
 	unsigned long lbasize;
 	u64 size;
-	u8 *uuid;
+	uuid_t *uuid;
 	int id;
 	int initial_offset;
 	u16 version_major;
@@ -350,7 +477,7 @@ enum nd_pfn_mode {
 
 struct nd_pfn {
 	int id;
-	u8 *uuid;
+	uuid_t *uuid;
 	struct device dev;
 	unsigned long align;
 	unsigned long npfns;
@@ -378,7 +505,7 @@ void wait_nvdimm_bus_probe_idle(struct device *dev);
 void nd_device_register(struct device *dev);
 void nd_device_unregister(struct device *dev, enum nd_async_mode mode);
 void nd_device_notify(struct device *dev, enum nvdimm_event event);
-int nd_uuid_store(struct device *dev, u8 **uuid_out, const char *buf,
+int nd_uuid_store(struct device *dev, uuid_t **uuid_out, const char *buf,
 		size_t len);
 ssize_t nd_size_select_show(unsigned long current_size,
 		const unsigned long *supported, char *buf);
@@ -561,6 +688,6 @@ static inline bool is_bad_pmem(struct badblocks *bb, sector_t sector,
 	return false;
 }
 resource_size_t nd_namespace_blk_validate(struct nd_namespace_blk *nsblk);
-const u8 *nd_dev_to_uuid(struct device *dev);
+const uuid_t *nd_dev_to_uuid(struct device *dev);
 bool pmem_should_map_pages(struct device *dev);
 #endif /* __ND_H__ */
diff --git a/drivers/nvdimm/pfn_devs.c b/drivers/nvdimm/pfn_devs.c
index b499df630d4d..58eda16f5c53 100644
--- a/drivers/nvdimm/pfn_devs.c
+++ b/drivers/nvdimm/pfn_devs.c
@@ -452,7 +452,7 @@ int nd_pfn_validate(struct nd_pfn *nd_pfn, const char *sig)
 	unsigned long align, start_pad;
 	struct nd_pfn_sb *pfn_sb = nd_pfn->pfn_sb;
 	struct nd_namespace_common *ndns = nd_pfn->ndns;
-	const u8 *parent_uuid = nd_dev_to_uuid(&ndns->dev);
+	const uuid_t *parent_uuid = nd_dev_to_uuid(&ndns->dev);
 
 	if (!pfn_sb || !ndns)
 		return -ENODEV;