libnvdimm/labels: Introduce CXL labels

Now that all of use sites of label data have been converted to nsl_*
helpers, introduce the CXL label format. The ->cxl flag in
nvdimm_drvdata indicates the label format the device expects. A
follow-on patch allows a bus provider to select the label style.

Note that the EFI definition of the labels represents the Linux "claim
class" with a GUID. The CXL definition of the labels stores the same
identifier in UUID byte order.

Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/163116432405.2460985.5547867384570123403.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

1 files changed, 105 insertions, 30 deletions

diff --git a/drivers/nvdimm/nd.h b/drivers/nvdimm/nd.h
index d57f95a48fe1..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,
@@ -52,122 +57,168 @@ 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)
 {
-	/* EFI labels do not have an nrange field */
+	if (ndd->cxl)
+		return __le16_to_cpu(nd_label->cxl.nrange);
 	return 1;
 }
 
@@ -175,26 +226,40 @@ 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)
 {
-	import_uuid(uuid, nd_label->uuid);
+	if (ndd->cxl)
+		import_uuid(uuid, nd_label->cxl.uuid);
+	else
+		import_uuid(uuid, nd_label->efi.uuid);
 	return uuid;
 }
 
@@ -202,7 +267,10 @@ static inline const uuid_t *nsl_set_uuid(struct nvdimm_drvdata *ndd,
 					 struct nd_namespace_label *nd_label,
 					 const uuid_t *uuid)
 {
-	export_uuid(nd_label->uuid, uuid);
+	if (ndd->cxl)
+		export_uuid(nd_label->cxl.uuid, uuid);
+	else
+		export_uuid(nd_label->efi.uuid, uuid);
 	return uuid;
 }
 
@@ -212,14 +280,19 @@ static inline bool nsl_uuid_equal(struct nvdimm_drvdata *ndd,
 {
 	uuid_t tmp;
 
-	import_uuid(&tmp, nd_label->uuid);
+	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)
 {
-	return nd_label->uuid;
+	if (ndd->cxl)
+		return nd_label->cxl.uuid;
+	return nd_label->efi.uuid;
 }
 
 bool nsl_validate_blk_isetcookie(struct nvdimm_drvdata *ndd,
@@ -278,8 +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...) \
@@ -359,6 +432,8 @@ 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;
 }