libnvdimm, region: move region-mapping input-paramters to nd_mapping_desc

Before we add more libnvdimm-private fields to nd_mapping make it clear
which parameters are input vs libnvdimm internals. Use struct
nd_mapping_desc instead of struct nd_mapping in nd_region_desc and make
struct nd_mapping private to libnvdimm.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

drivers/nvdimm/nd.h

@@ -98,6 +98,20 @@ struct nd_percpu_lane {
 	spinlock_t lock;
 };
 
+struct nd_mapping {
+	struct nvdimm *nvdimm;
+	struct nd_namespace_label **labels;
+	u64 start;
+	u64 size;
+	/*
+	 * @ndd is for private use at region enable / disable time for
+	 * get_ndd() + put_ndd(), all other nd_mapping to ndd
+	 * conversions use to_ndd() which respects enabled state of the
+	 * nvdimm.
+	 */
+	struct nvdimm_drvdata *ndd;
+};
+
 struct nd_region {
 	struct device dev;
 	struct ida ns_ida;

drivers/nvdimm/region_devs.c

@@ -755,10 +755,10 @@ static struct nd_region *nd_region_create(struct nvdimm_bus *nvdimm_bus,
 	int ro = 0;
 
 	for (i = 0; i < ndr_desc->num_mappings; i++) {
-		struct nd_mapping *nd_mapping = &ndr_desc->nd_mapping[i];
-		struct nvdimm *nvdimm = nd_mapping->nvdimm;
+		struct nd_mapping_desc *mapping = &ndr_desc->mapping[i];
+		struct nvdimm *nvdimm = mapping->nvdimm;
 
-		if ((nd_mapping->start | nd_mapping->size) % SZ_4K) {
+		if ((mapping->start | mapping->size) % SZ_4K) {
 			dev_err(&nvdimm_bus->dev, "%s: %s mapping%d is not 4K aligned\n",
 					caller, dev_name(&nvdimm->dev), i);
 
@@ -809,11 +809,13 @@ static struct nd_region *nd_region_create(struct nvdimm_bus *nvdimm_bus,
 		ndl->count = 0;
 	}
 
-	memcpy(nd_region->mapping, ndr_desc->nd_mapping,
-			sizeof(struct nd_mapping) * ndr_desc->num_mappings);
 	for (i = 0; i < ndr_desc->num_mappings; i++) {
-		struct nd_mapping *nd_mapping = &ndr_desc->nd_mapping[i];
-		struct nvdimm *nvdimm = nd_mapping->nvdimm;
+		struct nd_mapping_desc *mapping = &ndr_desc->mapping[i];
+		struct nvdimm *nvdimm = mapping->nvdimm;
+
+		nd_region->mapping[i].nvdimm = nvdimm;
+		nd_region->mapping[i].start = mapping->start;
+		nd_region->mapping[i].size = mapping->size;
 
 		get_device(&nvdimm->dev);
 	}