v4.19.13 snapshot.
diff --git a/drivers/nvdimm/label.c b/drivers/nvdimm/label.c
new file mode 100644
index 0000000..1d28cd6
--- /dev/null
+++ b/drivers/nvdimm/label.c
@@ -0,0 +1,1183 @@
+/*
+ * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ */
+#include <linux/device.h>
+#include <linux/ndctl.h>
+#include <linux/uuid.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include <linux/nd.h>
+#include "nd-core.h"
+#include "label.h"
+#include "nd.h"
+
+static guid_t nvdimm_btt_guid;
+static guid_t nvdimm_btt2_guid;
+static guid_t nvdimm_pfn_guid;
+static guid_t nvdimm_dax_guid;
+
+static u32 best_seq(u32 a, u32 b)
+{
+	a &= NSINDEX_SEQ_MASK;
+	b &= NSINDEX_SEQ_MASK;
+
+	if (a == 0 || a == b)
+		return b;
+	else if (b == 0)
+		return a;
+	else if (nd_inc_seq(a) == b)
+		return b;
+	else
+		return a;
+}
+
+unsigned sizeof_namespace_label(struct nvdimm_drvdata *ndd)
+{
+	return ndd->nslabel_size;
+}
+
+static size_t __sizeof_namespace_index(u32 nslot)
+{
+	return ALIGN(sizeof(struct nd_namespace_index) + DIV_ROUND_UP(nslot, 8),
+			NSINDEX_ALIGN);
+}
+
+static int __nvdimm_num_label_slots(struct nvdimm_drvdata *ndd,
+		size_t index_size)
+{
+	return (ndd->nsarea.config_size - index_size * 2) /
+			sizeof_namespace_label(ndd);
+}
+
+int nvdimm_num_label_slots(struct nvdimm_drvdata *ndd)
+{
+	u32 tmp_nslot, n;
+
+	tmp_nslot = ndd->nsarea.config_size / sizeof_namespace_label(ndd);
+	n = __sizeof_namespace_index(tmp_nslot) / NSINDEX_ALIGN;
+
+	return __nvdimm_num_label_slots(ndd, NSINDEX_ALIGN * n);
+}
+
+size_t sizeof_namespace_index(struct nvdimm_drvdata *ndd)
+{
+	u32 nslot, space, size;
+
+	/*
+	 * Per UEFI 2.7, the minimum size of the Label Storage Area is large
+	 * enough to hold 2 index blocks and 2 labels.  The minimum index
+	 * block size is 256 bytes, and the minimum label size is 256 bytes.
+	 */
+	nslot = nvdimm_num_label_slots(ndd);
+	space = ndd->nsarea.config_size - nslot * sizeof_namespace_label(ndd);
+	size = __sizeof_namespace_index(nslot) * 2;
+	if (size <= space && nslot >= 2)
+		return size / 2;
+
+	dev_err(ndd->dev, "label area (%d) too small to host (%d byte) labels\n",
+			ndd->nsarea.config_size, sizeof_namespace_label(ndd));
+	return 0;
+}
+
+static int __nd_label_validate(struct nvdimm_drvdata *ndd)
+{
+	/*
+	 * On media label format consists of two index blocks followed
+	 * by an array of labels.  None of these structures are ever
+	 * updated in place.  A sequence number tracks the current
+	 * active index and the next one to write, while labels are
+	 * written to free slots.
+	 *
+	 *     +------------+
+	 *     |            |
+	 *     |  nsindex0  |
+	 *     |            |
+	 *     +------------+
+	 *     |            |
+	 *     |  nsindex1  |
+	 *     |            |
+	 *     +------------+
+	 *     |   label0   |
+	 *     +------------+
+	 *     |   label1   |
+	 *     +------------+
+	 *     |            |
+	 *      ....nslot...
+	 *     |            |
+	 *     +------------+
+	 *     |   labelN   |
+	 *     +------------+
+	 */
+	struct nd_namespace_index *nsindex[] = {
+		to_namespace_index(ndd, 0),
+		to_namespace_index(ndd, 1),
+	};
+	const int num_index = ARRAY_SIZE(nsindex);
+	struct device *dev = ndd->dev;
+	bool valid[2] = { 0 };
+	int i, num_valid = 0;
+	u32 seq;
+
+	for (i = 0; i < num_index; i++) {
+		u32 nslot;
+		u8 sig[NSINDEX_SIG_LEN];
+		u64 sum_save, sum, size;
+		unsigned int version, labelsize;
+
+		memcpy(sig, nsindex[i]->sig, NSINDEX_SIG_LEN);
+		if (memcmp(sig, NSINDEX_SIGNATURE, NSINDEX_SIG_LEN) != 0) {
+			dev_dbg(dev, "nsindex%d signature invalid\n", i);
+			continue;
+		}
+
+		/* label sizes larger than 128 arrived with v1.2 */
+		version = __le16_to_cpu(nsindex[i]->major) * 100
+			+ __le16_to_cpu(nsindex[i]->minor);
+		if (version >= 102)
+			labelsize = 1 << (7 + nsindex[i]->labelsize);
+		else
+			labelsize = 128;
+
+		if (labelsize != sizeof_namespace_label(ndd)) {
+			dev_dbg(dev, "nsindex%d labelsize %d invalid\n",
+					i, nsindex[i]->labelsize);
+			continue;
+		}
+
+		sum_save = __le64_to_cpu(nsindex[i]->checksum);
+		nsindex[i]->checksum = __cpu_to_le64(0);
+		sum = nd_fletcher64(nsindex[i], sizeof_namespace_index(ndd), 1);
+		nsindex[i]->checksum = __cpu_to_le64(sum_save);
+		if (sum != sum_save) {
+			dev_dbg(dev, "nsindex%d checksum invalid\n", i);
+			continue;
+		}
+
+		seq = __le32_to_cpu(nsindex[i]->seq);
+		if ((seq & NSINDEX_SEQ_MASK) == 0) {
+			dev_dbg(dev, "nsindex%d sequence: %#x invalid\n", i, seq);
+			continue;
+		}
+
+		/* sanity check the index against expected values */
+		if (__le64_to_cpu(nsindex[i]->myoff)
+				!= i * sizeof_namespace_index(ndd)) {
+			dev_dbg(dev, "nsindex%d myoff: %#llx invalid\n",
+					i, (unsigned long long)
+					__le64_to_cpu(nsindex[i]->myoff));
+			continue;
+		}
+		if (__le64_to_cpu(nsindex[i]->otheroff)
+				!= (!i) * sizeof_namespace_index(ndd)) {
+			dev_dbg(dev, "nsindex%d otheroff: %#llx invalid\n",
+					i, (unsigned long long)
+					__le64_to_cpu(nsindex[i]->otheroff));
+			continue;
+		}
+
+		size = __le64_to_cpu(nsindex[i]->mysize);
+		if (size > sizeof_namespace_index(ndd)
+				|| size < sizeof(struct nd_namespace_index)) {
+			dev_dbg(dev, "nsindex%d mysize: %#llx invalid\n", i, size);
+			continue;
+		}
+
+		nslot = __le32_to_cpu(nsindex[i]->nslot);
+		if (nslot * sizeof_namespace_label(ndd)
+				+ 2 * sizeof_namespace_index(ndd)
+				> ndd->nsarea.config_size) {
+			dev_dbg(dev, "nsindex%d nslot: %u invalid, config_size: %#x\n",
+					i, nslot, ndd->nsarea.config_size);
+			continue;
+		}
+		valid[i] = true;
+		num_valid++;
+	}
+
+	switch (num_valid) {
+	case 0:
+		break;
+	case 1:
+		for (i = 0; i < num_index; i++)
+			if (valid[i])
+				return i;
+		/* can't have num_valid > 0 but valid[] = { false, false } */
+		WARN_ON(1);
+		break;
+	default:
+		/* pick the best index... */
+		seq = best_seq(__le32_to_cpu(nsindex[0]->seq),
+				__le32_to_cpu(nsindex[1]->seq));
+		if (seq == (__le32_to_cpu(nsindex[1]->seq) & NSINDEX_SEQ_MASK))
+			return 1;
+		else
+			return 0;
+		break;
+	}
+
+	return -1;
+}
+
+int nd_label_validate(struct nvdimm_drvdata *ndd)
+{
+	/*
+	 * In order to probe for and validate namespace index blocks we
+	 * need to know the size of the labels, and we can't trust the
+	 * size of the labels until we validate the index blocks.
+	 * Resolve this dependency loop by probing for known label
+	 * sizes, but default to v1.2 256-byte namespace labels if
+	 * discovery fails.
+	 */
+	int label_size[] = { 128, 256 };
+	int i, rc;
+
+	for (i = 0; i < ARRAY_SIZE(label_size); i++) {
+		ndd->nslabel_size = label_size[i];
+		rc = __nd_label_validate(ndd);
+		if (rc >= 0)
+			return rc;
+	}
+
+	return -1;
+}
+
+void nd_label_copy(struct nvdimm_drvdata *ndd, struct nd_namespace_index *dst,
+		struct nd_namespace_index *src)
+{
+	if (dst && src)
+		/* pass */;
+	else
+		return;
+
+	memcpy(dst, src, sizeof_namespace_index(ndd));
+}
+
+static struct nd_namespace_label *nd_label_base(struct nvdimm_drvdata *ndd)
+{
+	void *base = to_namespace_index(ndd, 0);
+
+	return base + 2 * sizeof_namespace_index(ndd);
+}
+
+static int to_slot(struct nvdimm_drvdata *ndd,
+		struct nd_namespace_label *nd_label)
+{
+	unsigned long label, base;
+
+	label = (unsigned long) nd_label;
+	base = (unsigned long) nd_label_base(ndd);
+
+	return (label - base) / sizeof_namespace_label(ndd);
+}
+
+static struct nd_namespace_label *to_label(struct nvdimm_drvdata *ndd, int slot)
+{
+	unsigned long label, base;
+
+	base = (unsigned long) nd_label_base(ndd);
+	label = base + sizeof_namespace_label(ndd) * slot;
+
+	return (struct nd_namespace_label *) label;
+}
+
+#define for_each_clear_bit_le(bit, addr, size) \
+	for ((bit) = find_next_zero_bit_le((addr), (size), 0);  \
+	     (bit) < (size);                                    \
+	     (bit) = find_next_zero_bit_le((addr), (size), (bit) + 1))
+
+/**
+ * preamble_index - common variable initialization for nd_label_* routines
+ * @ndd: dimm container for the relevant label set
+ * @idx: namespace_index index
+ * @nsindex_out: on return set to the currently active namespace index
+ * @free: on return set to the free label bitmap in the index
+ * @nslot: on return set to the number of slots in the label space
+ */
+static bool preamble_index(struct nvdimm_drvdata *ndd, int idx,
+		struct nd_namespace_index **nsindex_out,
+		unsigned long **free, u32 *nslot)
+{
+	struct nd_namespace_index *nsindex;
+
+	nsindex = to_namespace_index(ndd, idx);
+	if (nsindex == NULL)
+		return false;
+
+	*free = (unsigned long *) nsindex->free;
+	*nslot = __le32_to_cpu(nsindex->nslot);
+	*nsindex_out = nsindex;
+
+	return true;
+}
+
+char *nd_label_gen_id(struct nd_label_id *label_id, u8 *uuid, u32 flags)
+{
+	if (!label_id || !uuid)
+		return NULL;
+	snprintf(label_id->id, ND_LABEL_ID_SIZE, "%s-%pUb",
+			flags & NSLABEL_FLAG_LOCAL ? "blk" : "pmem", uuid);
+	return label_id->id;
+}
+
+static bool preamble_current(struct nvdimm_drvdata *ndd,
+		struct nd_namespace_index **nsindex,
+		unsigned long **free, u32 *nslot)
+{
+	return preamble_index(ndd, ndd->ns_current, nsindex,
+			free, nslot);
+}
+
+static bool preamble_next(struct nvdimm_drvdata *ndd,
+		struct nd_namespace_index **nsindex,
+		unsigned long **free, u32 *nslot)
+{
+	return preamble_index(ndd, ndd->ns_next, nsindex,
+			free, nslot);
+}
+
+static bool slot_valid(struct nvdimm_drvdata *ndd,
+		struct nd_namespace_label *nd_label, u32 slot)
+{
+	/* check that we are written where we expect to be written */
+	if (slot != __le32_to_cpu(nd_label->slot))
+		return false;
+
+	/* check that DPA allocations are page aligned */
+	if ((__le64_to_cpu(nd_label->dpa)
+				| __le64_to_cpu(nd_label->rawsize)) % SZ_4K)
+		return false;
+
+	/* check checksum */
+	if (namespace_label_has(ndd, checksum)) {
+		u64 sum, sum_save;
+
+		sum_save = __le64_to_cpu(nd_label->checksum);
+		nd_label->checksum = __cpu_to_le64(0);
+		sum = nd_fletcher64(nd_label, sizeof_namespace_label(ndd), 1);
+		nd_label->checksum = __cpu_to_le64(sum_save);
+		if (sum != sum_save) {
+			dev_dbg(ndd->dev, "fail checksum. slot: %d expect: %#llx\n",
+				slot, sum);
+			return false;
+		}
+	}
+
+	return true;
+}
+
+int nd_label_reserve_dpa(struct nvdimm_drvdata *ndd)
+{
+	struct nd_namespace_index *nsindex;
+	unsigned long *free;
+	u32 nslot, slot;
+
+	if (!preamble_current(ndd, &nsindex, &free, &nslot))
+		return 0; /* no label, nothing to reserve */
+
+	for_each_clear_bit_le(slot, free, nslot) {
+		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;
+		u32 flags;
+
+		nd_label = to_label(ndd, slot);
+
+		if (!slot_valid(ndd, nd_label, slot))
+			continue;
+
+		memcpy(label_uuid, nd_label->uuid, NSLABEL_UUID_LEN);
+		flags = __le32_to_cpu(nd_label->flags);
+		nd_label_gen_id(&label_id, label_uuid, flags);
+		res = nvdimm_allocate_dpa(ndd, &label_id,
+				__le64_to_cpu(nd_label->dpa),
+				__le64_to_cpu(nd_label->rawsize));
+		nd_dbg_dpa(nd_region, ndd, res, "reserve\n");
+		if (!res)
+			return -EBUSY;
+	}
+
+	return 0;
+}
+
+int nd_label_active_count(struct nvdimm_drvdata *ndd)
+{
+	struct nd_namespace_index *nsindex;
+	unsigned long *free;
+	u32 nslot, slot;
+	int count = 0;
+
+	if (!preamble_current(ndd, &nsindex, &free, &nslot))
+		return 0;
+
+	for_each_clear_bit_le(slot, free, nslot) {
+		struct nd_namespace_label *nd_label;
+
+		nd_label = to_label(ndd, slot);
+
+		if (!slot_valid(ndd, nd_label, slot)) {
+			u32 label_slot = __le32_to_cpu(nd_label->slot);
+			u64 size = __le64_to_cpu(nd_label->rawsize);
+			u64 dpa = __le64_to_cpu(nd_label->dpa);
+
+			dev_dbg(ndd->dev,
+				"slot%d invalid slot: %d dpa: %llx size: %llx\n",
+					slot, label_slot, dpa, size);
+			continue;
+		}
+		count++;
+	}
+	return count;
+}
+
+struct nd_namespace_label *nd_label_active(struct nvdimm_drvdata *ndd, int n)
+{
+	struct nd_namespace_index *nsindex;
+	unsigned long *free;
+	u32 nslot, slot;
+
+	if (!preamble_current(ndd, &nsindex, &free, &nslot))
+		return NULL;
+
+	for_each_clear_bit_le(slot, free, nslot) {
+		struct nd_namespace_label *nd_label;
+
+		nd_label = to_label(ndd, slot);
+		if (!slot_valid(ndd, nd_label, slot))
+			continue;
+
+		if (n-- == 0)
+			return to_label(ndd, slot);
+	}
+
+	return NULL;
+}
+
+u32 nd_label_alloc_slot(struct nvdimm_drvdata *ndd)
+{
+	struct nd_namespace_index *nsindex;
+	unsigned long *free;
+	u32 nslot, slot;
+
+	if (!preamble_next(ndd, &nsindex, &free, &nslot))
+		return UINT_MAX;
+
+	WARN_ON(!is_nvdimm_bus_locked(ndd->dev));
+
+	slot = find_next_bit_le(free, nslot, 0);
+	if (slot == nslot)
+		return UINT_MAX;
+
+	clear_bit_le(slot, free);
+
+	return slot;
+}
+
+bool nd_label_free_slot(struct nvdimm_drvdata *ndd, u32 slot)
+{
+	struct nd_namespace_index *nsindex;
+	unsigned long *free;
+	u32 nslot;
+
+	if (!preamble_next(ndd, &nsindex, &free, &nslot))
+		return false;
+
+	WARN_ON(!is_nvdimm_bus_locked(ndd->dev));
+
+	if (slot < nslot)
+		return !test_and_set_bit_le(slot, free);
+	return false;
+}
+
+u32 nd_label_nfree(struct nvdimm_drvdata *ndd)
+{
+	struct nd_namespace_index *nsindex;
+	unsigned long *free;
+	u32 nslot;
+
+	WARN_ON(!is_nvdimm_bus_locked(ndd->dev));
+
+	if (!preamble_next(ndd, &nsindex, &free, &nslot))
+		return nvdimm_num_label_slots(ndd);
+
+	return bitmap_weight(free, nslot);
+}
+
+static int nd_label_write_index(struct nvdimm_drvdata *ndd, int index, u32 seq,
+		unsigned long flags)
+{
+	struct nd_namespace_index *nsindex;
+	unsigned long offset;
+	u64 checksum;
+	u32 nslot;
+	int rc;
+
+	nsindex = to_namespace_index(ndd, index);
+	if (flags & ND_NSINDEX_INIT)
+		nslot = nvdimm_num_label_slots(ndd);
+	else
+		nslot = __le32_to_cpu(nsindex->nslot);
+
+	memcpy(nsindex->sig, NSINDEX_SIGNATURE, NSINDEX_SIG_LEN);
+	memset(&nsindex->flags, 0, 3);
+	nsindex->labelsize = sizeof_namespace_label(ndd) >> 8;
+	nsindex->seq = __cpu_to_le32(seq);
+	offset = (unsigned long) nsindex
+		- (unsigned long) to_namespace_index(ndd, 0);
+	nsindex->myoff = __cpu_to_le64(offset);
+	nsindex->mysize = __cpu_to_le64(sizeof_namespace_index(ndd));
+	offset = (unsigned long) to_namespace_index(ndd,
+			nd_label_next_nsindex(index))
+		- (unsigned long) to_namespace_index(ndd, 0);
+	nsindex->otheroff = __cpu_to_le64(offset);
+	offset = (unsigned long) nd_label_base(ndd)
+		- (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)
+		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;
+		u32 nfree = ALIGN(nslot, BITS_PER_LONG);
+		int last_bits, i;
+
+		memset(nsindex->free, 0xff, nfree / 8);
+		for (i = 0, last_bits = nfree - nslot; i < last_bits; i++)
+			clear_bit_le(nslot + i, free);
+	}
+	checksum = nd_fletcher64(nsindex, sizeof_namespace_index(ndd), 1);
+	nsindex->checksum = __cpu_to_le64(checksum);
+	rc = nvdimm_set_config_data(ndd, __le64_to_cpu(nsindex->myoff),
+			nsindex, sizeof_namespace_index(ndd));
+	if (rc < 0)
+		return rc;
+
+	if (flags & ND_NSINDEX_INIT)
+		return 0;
+
+	/* copy the index we just wrote to the new 'next' */
+	WARN_ON(index != ndd->ns_next);
+	nd_label_copy(ndd, to_current_namespace_index(ndd), nsindex);
+	ndd->ns_current = nd_label_next_nsindex(ndd->ns_current);
+	ndd->ns_next = nd_label_next_nsindex(ndd->ns_next);
+	WARN_ON(ndd->ns_current == ndd->ns_next);
+
+	return 0;
+}
+
+static unsigned long nd_label_offset(struct nvdimm_drvdata *ndd,
+		struct nd_namespace_label *nd_label)
+{
+	return (unsigned long) nd_label
+		- (unsigned long) to_namespace_index(ndd, 0);
+}
+
+enum nvdimm_claim_class to_nvdimm_cclass(guid_t *guid)
+{
+	if (guid_equal(guid, &nvdimm_btt_guid))
+		return NVDIMM_CCLASS_BTT;
+	else if (guid_equal(guid, &nvdimm_btt2_guid))
+		return NVDIMM_CCLASS_BTT2;
+	else if (guid_equal(guid, &nvdimm_pfn_guid))
+		return NVDIMM_CCLASS_PFN;
+	else if (guid_equal(guid, &nvdimm_dax_guid))
+		return NVDIMM_CCLASS_DAX;
+	else if (guid_equal(guid, &guid_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)
+{
+	if (claim_class == NVDIMM_CCLASS_BTT)
+		return &nvdimm_btt_guid;
+	else if (claim_class == NVDIMM_CCLASS_BTT2)
+		return &nvdimm_btt2_guid;
+	else if (claim_class == NVDIMM_CCLASS_PFN)
+		return &nvdimm_pfn_guid;
+	else if (claim_class == NVDIMM_CCLASS_DAX)
+		return &nvdimm_dax_guid;
+	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 guid.
+		 */
+		return target;
+	} else
+		return &guid_null;
+}
+
+static int __pmem_label_update(struct nd_region *nd_region,
+		struct nd_mapping *nd_mapping, struct nd_namespace_pmem *nspm,
+		int pos)
+{
+	struct nd_namespace_common *ndns = &nspm->nsio.common;
+	struct nd_interleave_set *nd_set = nd_region->nd_set;
+	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
+	struct nd_label_ent *label_ent, *victim = NULL;
+	struct nd_namespace_label *nd_label;
+	struct nd_namespace_index *nsindex;
+	struct nd_label_id label_id;
+	struct resource *res;
+	unsigned long *free;
+	u32 nslot, slot;
+	size_t offset;
+	u64 cookie;
+	int rc;
+
+	if (!preamble_next(ndd, &nsindex, &free, &nslot))
+		return -ENXIO;
+
+	cookie = nd_region_interleave_set_cookie(nd_region, nsindex);
+	nd_label_gen_id(&label_id, nspm->uuid, 0);
+	for_each_dpa_resource(ndd, res)
+		if (strcmp(res->name, label_id.id) == 0)
+			break;
+
+	if (!res) {
+		WARN_ON_ONCE(1);
+		return -ENXIO;
+	}
+
+	/* allocate and write the label to the staging (next) index */
+	slot = nd_label_alloc_slot(ndd);
+	if (slot == UINT_MAX)
+		return -ENXIO;
+	dev_dbg(ndd->dev, "allocated: %d\n", slot);
+
+	nd_label = to_label(ndd, slot);
+	memset(nd_label, 0, sizeof_namespace_label(ndd));
+	memcpy(nd_label->uuid, nspm->uuid, NSLABEL_UUID_LEN);
+	if (nspm->alt_name)
+		memcpy(nd_label->name, nspm->alt_name, NSLABEL_NAME_LEN);
+	nd_label->flags = __cpu_to_le32(NSLABEL_FLAG_UPDATING);
+	nd_label->nlabel = __cpu_to_le16(nd_region->ndr_mappings);
+	nd_label->position = __cpu_to_le16(pos);
+	nd_label->isetcookie = __cpu_to_le64(cookie);
+	nd_label->rawsize = __cpu_to_le64(resource_size(res));
+	nd_label->lbasize = __cpu_to_le64(nspm->lbasize);
+	nd_label->dpa = __cpu_to_le64(res->start);
+	nd_label->slot = __cpu_to_le32(slot);
+	if (namespace_label_has(ndd, type_guid))
+		guid_copy(&nd_label->type_guid, &nd_set->type_guid);
+	if (namespace_label_has(ndd, abstraction_guid))
+		guid_copy(&nd_label->abstraction_guid,
+				to_abstraction_guid(ndns->claim_class,
+					&nd_label->abstraction_guid));
+	if (namespace_label_has(ndd, checksum)) {
+		u64 sum;
+
+		nd_label->checksum = __cpu_to_le64(0);
+		sum = nd_fletcher64(nd_label, sizeof_namespace_label(ndd), 1);
+		nd_label->checksum = __cpu_to_le64(sum);
+	}
+	nd_dbg_dpa(nd_region, ndd, res, "\n");
+
+	/* update label */
+	offset = nd_label_offset(ndd, nd_label);
+	rc = nvdimm_set_config_data(ndd, offset, nd_label,
+			sizeof_namespace_label(ndd));
+	if (rc < 0)
+		return rc;
+
+	/* Garbage collect the previous label */
+	mutex_lock(&nd_mapping->lock);
+	list_for_each_entry(label_ent, &nd_mapping->labels, list) {
+		if (!label_ent->label)
+			continue;
+		if (memcmp(nspm->uuid, label_ent->label->uuid,
+					NSLABEL_UUID_LEN) != 0)
+			continue;
+		victim = label_ent;
+		list_move_tail(&victim->list, &nd_mapping->labels);
+		break;
+	}
+	if (victim) {
+		dev_dbg(ndd->dev, "free: %d\n", slot);
+		slot = to_slot(ndd, victim->label);
+		nd_label_free_slot(ndd, slot);
+		victim->label = NULL;
+	}
+
+	/* update index */
+	rc = nd_label_write_index(ndd, ndd->ns_next,
+			nd_inc_seq(__le32_to_cpu(nsindex->seq)), 0);
+	if (rc == 0) {
+		list_for_each_entry(label_ent, &nd_mapping->labels, list)
+			if (!label_ent->label) {
+				label_ent->label = nd_label;
+				nd_label = NULL;
+				break;
+			}
+		dev_WARN_ONCE(&nspm->nsio.common.dev, nd_label,
+				"failed to track label: %d\n",
+				to_slot(ndd, nd_label));
+		if (nd_label)
+			rc = -ENXIO;
+	}
+	mutex_unlock(&nd_mapping->lock);
+
+	return rc;
+}
+
+static bool is_old_resource(struct resource *res, struct resource **list, int n)
+{
+	int i;
+
+	if (res->flags & DPA_RESOURCE_ADJUSTED)
+		return false;
+	for (i = 0; i < n; i++)
+		if (res == list[i])
+			return true;
+	return false;
+}
+
+static struct resource *to_resource(struct nvdimm_drvdata *ndd,
+		struct nd_namespace_label *nd_label)
+{
+	struct resource *res;
+
+	for_each_dpa_resource(ndd, res) {
+		if (res->start != __le64_to_cpu(nd_label->dpa))
+			continue;
+		if (resource_size(res) != __le64_to_cpu(nd_label->rawsize))
+			continue;
+		return res;
+	}
+
+	return NULL;
+}
+
+/*
+ * 1/ Account all the labels that can be freed after this update
+ * 2/ Allocate and write the label to the staging (next) index
+ * 3/ Record the resources in the namespace device
+ */
+static int __blk_label_update(struct nd_region *nd_region,
+		struct nd_mapping *nd_mapping, struct nd_namespace_blk *nsblk,
+		int num_labels)
+{
+	int i, alloc, victims, nfree, old_num_resources, nlabel, rc = -ENXIO;
+	struct nd_interleave_set *nd_set = nd_region->nd_set;
+	struct nd_namespace_common *ndns = &nsblk->common;
+	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
+	struct nd_namespace_label *nd_label;
+	struct nd_label_ent *label_ent, *e;
+	struct nd_namespace_index *nsindex;
+	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;
+
+	if (!preamble_next(ndd, &nsindex, &free, &nslot))
+		return -ENXIO;
+
+	old_res_list = nsblk->res;
+	nfree = nd_label_nfree(ndd);
+	old_num_resources = nsblk->num_resources;
+	nd_label_gen_id(&label_id, nsblk->uuid, NSLABEL_FLAG_LOCAL);
+
+	/*
+	 * We need to loop over the old resources a few times, which seems a
+	 * bit inefficient, but we need to know that we have the label
+	 * space before we start mutating the tracking structures.
+	 * Otherwise the recovery method of last resort for userspace is
+	 * disable and re-enable the parent region.
+	 */
+	alloc = 0;
+	for_each_dpa_resource(ndd, res) {
+		if (strcmp(res->name, label_id.id) != 0)
+			continue;
+		if (!is_old_resource(res, old_res_list, old_num_resources))
+			alloc++;
+	}
+
+	victims = 0;
+	if (old_num_resources) {
+		/* convert old local-label-map to dimm-slot victim-map */
+		victim_map = kcalloc(BITS_TO_LONGS(nslot), sizeof(long),
+				GFP_KERNEL);
+		if (!victim_map)
+			return -ENOMEM;
+
+		/* 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)
+				continue;
+			res = to_resource(ndd, nd_label);
+			if (res && is_old_resource(res, old_res_list,
+						old_num_resources))
+				continue;
+			slot = to_slot(ndd, nd_label);
+			set_bit(slot, victim_map);
+			victims++;
+		}
+	}
+
+	/* don't allow updates that consume the last label */
+	if (nfree - alloc < 0 || nfree - alloc + victims < 1) {
+		dev_info(&nsblk->common.dev, "insufficient label space\n");
+		kfree(victim_map);
+		return -ENOSPC;
+	}
+	/* from here on we need to abort on error */
+
+
+	/* assign all resources to the namespace before writing the labels */
+	nsblk->res = NULL;
+	nsblk->num_resources = 0;
+	for_each_dpa_resource(ndd, res) {
+		if (strcmp(res->name, label_id.id) != 0)
+			continue;
+		if (!nsblk_add_resource(nd_region, ndd, nsblk, res->start)) {
+			rc = -ENOMEM;
+			goto abort;
+		}
+	}
+
+	/*
+	 * Find the resource associated with the first label in the set
+	 * per the v1.2 namespace specification.
+	 */
+	for (i = 0; i < nsblk->num_resources; i++) {
+		struct resource *min = nsblk->res[min_dpa_idx];
+
+		res = nsblk->res[i];
+		if (res->start < min->start)
+			min_dpa_idx = i;
+	}
+
+	for (i = 0; i < nsblk->num_resources; i++) {
+		size_t offset;
+
+		res = nsblk->res[i];
+		if (is_old_resource(res, old_res_list, old_num_resources))
+			continue; /* carry-over */
+		slot = nd_label_alloc_slot(ndd);
+		if (slot == UINT_MAX)
+			goto abort;
+		dev_dbg(ndd->dev, "allocated: %d\n", slot);
+
+		nd_label = to_label(ndd, slot);
+		memset(nd_label, 0, sizeof_namespace_label(ndd));
+		memcpy(nd_label->uuid, nsblk->uuid, NSLABEL_UUID_LEN);
+		if (nsblk->alt_name)
+			memcpy(nd_label->name, nsblk->alt_name,
+					NSLABEL_NAME_LEN);
+		nd_label->flags = __cpu_to_le32(NSLABEL_FLAG_LOCAL);
+
+		/*
+		 * Use the presence of the type_guid as a flag to
+		 * determine isetcookie usage and nlabel + position
+		 * policy for blk-aperture namespaces.
+		 */
+		if (namespace_label_has(ndd, type_guid)) {
+			if (i == min_dpa_idx) {
+				nd_label->nlabel = __cpu_to_le16(nsblk->num_resources);
+				nd_label->position = __cpu_to_le16(0);
+			} else {
+				nd_label->nlabel = __cpu_to_le16(0xffff);
+				nd_label->position = __cpu_to_le16(0xffff);
+			}
+			nd_label->isetcookie = __cpu_to_le64(nd_set->cookie2);
+		} else {
+			nd_label->nlabel = __cpu_to_le16(0); /* N/A */
+			nd_label->position = __cpu_to_le16(0); /* N/A */
+			nd_label->isetcookie = __cpu_to_le64(0); /* N/A */
+		}
+
+		nd_label->dpa = __cpu_to_le64(res->start);
+		nd_label->rawsize = __cpu_to_le64(resource_size(res));
+		nd_label->lbasize = __cpu_to_le64(nsblk->lbasize);
+		nd_label->slot = __cpu_to_le32(slot);
+		if (namespace_label_has(ndd, type_guid))
+			guid_copy(&nd_label->type_guid, &nd_set->type_guid);
+		if (namespace_label_has(ndd, abstraction_guid))
+			guid_copy(&nd_label->abstraction_guid,
+					to_abstraction_guid(ndns->claim_class,
+						&nd_label->abstraction_guid));
+
+		if (namespace_label_has(ndd, checksum)) {
+			u64 sum;
+
+			nd_label->checksum = __cpu_to_le64(0);
+			sum = nd_fletcher64(nd_label,
+					sizeof_namespace_label(ndd), 1);
+			nd_label->checksum = __cpu_to_le64(sum);
+		}
+
+		/* update label */
+		offset = nd_label_offset(ndd, nd_label);
+		rc = nvdimm_set_config_data(ndd, offset, nd_label,
+				sizeof_namespace_label(ndd));
+		if (rc < 0)
+			goto abort;
+	}
+
+	/* free up now unused slots in the new index */
+	for_each_set_bit(slot, victim_map, victim_map ? nslot : 0) {
+		dev_dbg(ndd->dev, "free: %d\n", slot);
+		nd_label_free_slot(ndd, slot);
+	}
+
+	/* update index */
+	rc = nd_label_write_index(ndd, ndd->ns_next,
+			nd_inc_seq(__le32_to_cpu(nsindex->seq)), 0);
+	if (rc)
+		goto abort;
+
+	/*
+	 * Now that the on-dimm labels are up to date, fix up the tracking
+	 * entries in nd_mapping->labels
+	 */
+	nlabel = 0;
+	mutex_lock(&nd_mapping->lock);
+	list_for_each_entry_safe(label_ent, e, &nd_mapping->labels, list) {
+		nd_label = label_ent->label;
+		if (!nd_label)
+			continue;
+		nlabel++;
+		memcpy(uuid, nd_label->uuid, NSLABEL_UUID_LEN);
+		if (memcmp(uuid, nsblk->uuid, NSLABEL_UUID_LEN) != 0)
+			continue;
+		nlabel--;
+		list_move(&label_ent->list, &list);
+		label_ent->label = NULL;
+	}
+	list_splice_tail_init(&list, &nd_mapping->labels);
+	mutex_unlock(&nd_mapping->lock);
+
+	if (nlabel + nsblk->num_resources > num_labels) {
+		/*
+		 * Bug, we can't end up with more resources than
+		 * available labels
+		 */
+		WARN_ON_ONCE(1);
+		rc = -ENXIO;
+		goto out;
+	}
+
+	mutex_lock(&nd_mapping->lock);
+	label_ent = list_first_entry_or_null(&nd_mapping->labels,
+			typeof(*label_ent), list);
+	if (!label_ent) {
+		WARN_ON(1);
+		mutex_unlock(&nd_mapping->lock);
+		rc = -ENXIO;
+		goto out;
+	}
+	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)
+			continue;
+		res = to_resource(ndd, nd_label);
+		res->flags &= ~DPA_RESOURCE_ADJUSTED;
+		dev_vdbg(&nsblk->common.dev, "assign label slot: %d\n", slot);
+		list_for_each_entry_from(label_ent, &nd_mapping->labels, list) {
+			if (label_ent->label)
+				continue;
+			label_ent->label = nd_label;
+			nd_label = NULL;
+			break;
+		}
+		if (nd_label)
+			dev_WARN(&nsblk->common.dev,
+					"failed to track label slot%d\n", slot);
+	}
+	mutex_unlock(&nd_mapping->lock);
+
+ out:
+	kfree(old_res_list);
+	kfree(victim_map);
+	return rc;
+
+ abort:
+	/*
+	 * 1/ repair the allocated label bitmap in the index
+	 * 2/ restore the resource list
+	 */
+	nd_label_copy(ndd, nsindex, to_current_namespace_index(ndd));
+	kfree(nsblk->res);
+	nsblk->res = old_res_list;
+	nsblk->num_resources = old_num_resources;
+	old_res_list = NULL;
+	goto out;
+}
+
+static int init_labels(struct nd_mapping *nd_mapping, int num_labels)
+{
+	int i, old_num_labels = 0;
+	struct nd_label_ent *label_ent;
+	struct nd_namespace_index *nsindex;
+	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
+
+	mutex_lock(&nd_mapping->lock);
+	list_for_each_entry(label_ent, &nd_mapping->labels, list)
+		old_num_labels++;
+	mutex_unlock(&nd_mapping->lock);
+
+	/*
+	 * We need to preserve all the old labels for the mapping so
+	 * they can be garbage collected after writing the new labels.
+	 */
+	for (i = old_num_labels; i < num_labels; i++) {
+		label_ent = kzalloc(sizeof(*label_ent), GFP_KERNEL);
+		if (!label_ent)
+			return -ENOMEM;
+		mutex_lock(&nd_mapping->lock);
+		list_add_tail(&label_ent->list, &nd_mapping->labels);
+		mutex_unlock(&nd_mapping->lock);
+	}
+
+	if (ndd->ns_current == -1 || ndd->ns_next == -1)
+		/* pass */;
+	else
+		return max(num_labels, old_num_labels);
+
+	nsindex = to_namespace_index(ndd, 0);
+	memset(nsindex, 0, ndd->nsarea.config_size);
+	for (i = 0; i < 2; i++) {
+		int rc = nd_label_write_index(ndd, i, 3 - i, ND_NSINDEX_INIT);
+
+		if (rc)
+			return rc;
+	}
+	ndd->ns_next = 1;
+	ndd->ns_current = 0;
+
+	return max(num_labels, old_num_labels);
+}
+
+static int del_labels(struct nd_mapping *nd_mapping, u8 *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;
+	int active = 0;
+
+	if (!uuid)
+		return 0;
+
+	/* no index || no labels == nothing to delete */
+	if (!preamble_next(ndd, &nsindex, &free, &nslot))
+		return 0;
+
+	mutex_lock(&nd_mapping->lock);
+	list_for_each_entry_safe(label_ent, e, &nd_mapping->labels, list) {
+		struct nd_namespace_label *nd_label = label_ent->label;
+
+		if (!nd_label)
+			continue;
+		active++;
+		memcpy(label_uuid, nd_label->uuid, NSLABEL_UUID_LEN);
+		if (memcmp(label_uuid, uuid, NSLABEL_UUID_LEN) != 0)
+			continue;
+		active--;
+		slot = to_slot(ndd, nd_label);
+		nd_label_free_slot(ndd, slot);
+		dev_dbg(ndd->dev, "free: %d\n", slot);
+		list_move_tail(&label_ent->list, &list);
+		label_ent->label = NULL;
+	}
+	list_splice_tail_init(&list, &nd_mapping->labels);
+
+	if (active == 0) {
+		nd_mapping_free_labels(nd_mapping);
+		dev_dbg(ndd->dev, "no more active labels\n");
+	}
+	mutex_unlock(&nd_mapping->lock);
+
+	return nd_label_write_index(ndd, ndd->ns_next,
+			nd_inc_seq(__le32_to_cpu(nsindex->seq)), 0);
+}
+
+int nd_pmem_namespace_label_update(struct nd_region *nd_region,
+		struct nd_namespace_pmem *nspm, resource_size_t size)
+{
+	int i;
+
+	for (i = 0; i < nd_region->ndr_mappings; i++) {
+		struct nd_mapping *nd_mapping = &nd_region->mapping[i];
+		struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
+		struct resource *res;
+		int rc, count = 0;
+
+		if (size == 0) {
+			rc = del_labels(nd_mapping, nspm->uuid);
+			if (rc)
+				return rc;
+			continue;
+		}
+
+		for_each_dpa_resource(ndd, res)
+			if (strncmp(res->name, "pmem", 4) == 0)
+				count++;
+		WARN_ON_ONCE(!count);
+
+		rc = init_labels(nd_mapping, count);
+		if (rc < 0)
+			return rc;
+
+		rc = __pmem_label_update(nd_region, nd_mapping, nspm, i);
+		if (rc)
+			return rc;
+	}
+
+	return 0;
+}
+
+int nd_blk_namespace_label_update(struct nd_region *nd_region,
+		struct nd_namespace_blk *nsblk, resource_size_t size)
+{
+	struct nd_mapping *nd_mapping = &nd_region->mapping[0];
+	struct resource *res;
+	int count = 0;
+
+	if (size == 0)
+		return del_labels(nd_mapping, nsblk->uuid);
+
+	for_each_dpa_resource(to_ndd(nd_mapping), res)
+		count++;
+
+	count = init_labels(nd_mapping, count);
+	if (count < 0)
+		return count;
+
+	return __blk_label_update(nd_region, nd_mapping, nsblk, count);
+}
+
+int __init nd_label_init(void)
+{
+	WARN_ON(guid_parse(NVDIMM_BTT_GUID, &nvdimm_btt_guid));
+	WARN_ON(guid_parse(NVDIMM_BTT2_GUID, &nvdimm_btt2_guid));
+	WARN_ON(guid_parse(NVDIMM_PFN_GUID, &nvdimm_pfn_guid));
+	WARN_ON(guid_parse(NVDIMM_DAX_GUID, &nvdimm_dax_guid));
+
+	return 0;
+}