blob: a5233422f9dc5f770b98d0555560fb87a5f83ff0 [file] [log] [blame]
/*
* 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/scatterlist.h>
#include <linux/highmem.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/sort.h>
#include <linux/io.h>
#include <linux/nd.h>
#include "nd-core.h"
#include "nd.h"
static DEFINE_IDA(region_ida);
static void nd_region_release(struct device *dev)
{
struct nd_region *nd_region = to_nd_region(dev);
u16 i;
for (i = 0; i < nd_region->ndr_mappings; i++) {
struct nd_mapping *nd_mapping = &nd_region->mapping[i];
struct nvdimm *nvdimm = nd_mapping->nvdimm;
put_device(&nvdimm->dev);
}
free_percpu(nd_region->lane);
ida_simple_remove(&region_ida, nd_region->id);
if (is_nd_blk(dev))
kfree(to_nd_blk_region(dev));
else
kfree(nd_region);
}
static struct device_type nd_blk_device_type = {
.name = "nd_blk",
.release = nd_region_release,
};
static struct device_type nd_pmem_device_type = {
.name = "nd_pmem",
.release = nd_region_release,
};
static struct device_type nd_volatile_device_type = {
.name = "nd_volatile",
.release = nd_region_release,
};
bool is_nd_pmem(struct device *dev)
{
return dev ? dev->type == &nd_pmem_device_type : false;
}
bool is_nd_blk(struct device *dev)
{
return dev ? dev->type == &nd_blk_device_type : false;
}
struct nd_region *to_nd_region(struct device *dev)
{
struct nd_region *nd_region = container_of(dev, struct nd_region, dev);
WARN_ON(dev->type->release != nd_region_release);
return nd_region;
}
EXPORT_SYMBOL_GPL(to_nd_region);
struct nd_blk_region *to_nd_blk_region(struct device *dev)
{
struct nd_region *nd_region = to_nd_region(dev);
WARN_ON(!is_nd_blk(dev));
return container_of(nd_region, struct nd_blk_region, nd_region);
}
EXPORT_SYMBOL_GPL(to_nd_blk_region);
void *nd_region_provider_data(struct nd_region *nd_region)
{
return nd_region->provider_data;
}
EXPORT_SYMBOL_GPL(nd_region_provider_data);
void *nd_blk_region_provider_data(struct nd_blk_region *ndbr)
{
return ndbr->blk_provider_data;
}
EXPORT_SYMBOL_GPL(nd_blk_region_provider_data);
void nd_blk_region_set_provider_data(struct nd_blk_region *ndbr, void *data)
{
ndbr->blk_provider_data = data;
}
EXPORT_SYMBOL_GPL(nd_blk_region_set_provider_data);
/**
* nd_region_to_nstype() - region to an integer namespace type
* @nd_region: region-device to interrogate
*
* This is the 'nstype' attribute of a region as well, an input to the
* MODALIAS for namespace devices, and bit number for a nvdimm_bus to match
* namespace devices with namespace drivers.
*/
int nd_region_to_nstype(struct nd_region *nd_region)
{
if (is_nd_pmem(&nd_region->dev)) {
u16 i, alias;
for (i = 0, alias = 0; i < nd_region->ndr_mappings; i++) {
struct nd_mapping *nd_mapping = &nd_region->mapping[i];
struct nvdimm *nvdimm = nd_mapping->nvdimm;
if (nvdimm->flags & NDD_ALIASING)
alias++;
}
if (alias)
return ND_DEVICE_NAMESPACE_PMEM;
else
return ND_DEVICE_NAMESPACE_IO;
} else if (is_nd_blk(&nd_region->dev)) {
return ND_DEVICE_NAMESPACE_BLK;
}
return 0;
}
EXPORT_SYMBOL(nd_region_to_nstype);
static int is_uuid_busy(struct device *dev, void *data)
{
struct nd_region *nd_region = to_nd_region(dev->parent);
u8 *uuid = data;
switch (nd_region_to_nstype(nd_region)) {
case ND_DEVICE_NAMESPACE_PMEM: {
struct nd_namespace_pmem *nspm = to_nd_namespace_pmem(dev);
if (!nspm->uuid)
break;
if (memcmp(uuid, nspm->uuid, NSLABEL_UUID_LEN) == 0)
return -EBUSY;
break;
}
case ND_DEVICE_NAMESPACE_BLK: {
struct nd_namespace_blk *nsblk = to_nd_namespace_blk(dev);
if (!nsblk->uuid)
break;
if (memcmp(uuid, nsblk->uuid, NSLABEL_UUID_LEN) == 0)
return -EBUSY;
break;
}
default:
break;
}
return 0;
}
static int is_namespace_uuid_busy(struct device *dev, void *data)
{
if (is_nd_pmem(dev) || is_nd_blk(dev))
return device_for_each_child(dev, data, is_uuid_busy);
return 0;
}
/**
* nd_is_uuid_unique - verify that no other namespace has @uuid
* @dev: any device on a nvdimm_bus
* @uuid: uuid to check
*/
bool nd_is_uuid_unique(struct device *dev, u8 *uuid)
{
struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
if (!nvdimm_bus)
return false;
WARN_ON_ONCE(!is_nvdimm_bus_locked(&nvdimm_bus->dev));
if (device_for_each_child(&nvdimm_bus->dev, uuid,
is_namespace_uuid_busy) != 0)
return false;
return true;
}
static ssize_t size_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct nd_region *nd_region = to_nd_region(dev);
unsigned long long size = 0;
if (is_nd_pmem(dev)) {
size = nd_region->ndr_size;
} else if (nd_region->ndr_mappings == 1) {
struct nd_mapping *nd_mapping = &nd_region->mapping[0];
size = nd_mapping->size;
}
return sprintf(buf, "%llu\n", size);
}
static DEVICE_ATTR_RO(size);
static ssize_t mappings_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct nd_region *nd_region = to_nd_region(dev);
return sprintf(buf, "%d\n", nd_region->ndr_mappings);
}
static DEVICE_ATTR_RO(mappings);
static ssize_t nstype_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct nd_region *nd_region = to_nd_region(dev);
return sprintf(buf, "%d\n", nd_region_to_nstype(nd_region));
}
static DEVICE_ATTR_RO(nstype);
static ssize_t set_cookie_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct nd_region *nd_region = to_nd_region(dev);
struct nd_interleave_set *nd_set = nd_region->nd_set;
if (is_nd_pmem(dev) && nd_set)
/* pass, should be precluded by region_visible */;
else
return -ENXIO;
return sprintf(buf, "%#llx\n", nd_set->cookie);
}
static DEVICE_ATTR_RO(set_cookie);
resource_size_t nd_region_available_dpa(struct nd_region *nd_region)
{
resource_size_t blk_max_overlap = 0, available, overlap;
int i;
WARN_ON(!is_nvdimm_bus_locked(&nd_region->dev));
retry:
available = 0;
overlap = blk_max_overlap;
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);
/* if a dimm is disabled the available capacity is zero */
if (!ndd)
return 0;
if (is_nd_pmem(&nd_region->dev)) {
available += nd_pmem_available_dpa(nd_region,
nd_mapping, &overlap);
if (overlap > blk_max_overlap) {
blk_max_overlap = overlap;
goto retry;
}
} else if (is_nd_blk(&nd_region->dev)) {
available += nd_blk_available_dpa(nd_mapping);
}
}
return available;
}
static ssize_t available_size_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct nd_region *nd_region = to_nd_region(dev);
unsigned long long available = 0;
/*
* Flush in-flight updates and grab a snapshot of the available
* size. Of course, this value is potentially invalidated the
* memory nvdimm_bus_lock() is dropped, but that's userspace's
* problem to not race itself.
*/
nvdimm_bus_lock(dev);
wait_nvdimm_bus_probe_idle(dev);
available = nd_region_available_dpa(nd_region);
nvdimm_bus_unlock(dev);
return sprintf(buf, "%llu\n", available);
}
static DEVICE_ATTR_RO(available_size);
static ssize_t init_namespaces_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct nd_region_namespaces *num_ns = dev_get_drvdata(dev);
ssize_t rc;
nvdimm_bus_lock(dev);
if (num_ns)
rc = sprintf(buf, "%d/%d\n", num_ns->active, num_ns->count);
else
rc = -ENXIO;
nvdimm_bus_unlock(dev);
return rc;
}
static DEVICE_ATTR_RO(init_namespaces);
static ssize_t namespace_seed_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct nd_region *nd_region = to_nd_region(dev);
ssize_t rc;
nvdimm_bus_lock(dev);
if (nd_region->ns_seed)
rc = sprintf(buf, "%s\n", dev_name(nd_region->ns_seed));
else
rc = sprintf(buf, "\n");
nvdimm_bus_unlock(dev);
return rc;
}
static DEVICE_ATTR_RO(namespace_seed);
static ssize_t btt_seed_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct nd_region *nd_region = to_nd_region(dev);
ssize_t rc;
nvdimm_bus_lock(dev);
if (nd_region->btt_seed)
rc = sprintf(buf, "%s\n", dev_name(nd_region->btt_seed));
else
rc = sprintf(buf, "\n");
nvdimm_bus_unlock(dev);
return rc;
}
static DEVICE_ATTR_RO(btt_seed);
static ssize_t read_only_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct nd_region *nd_region = to_nd_region(dev);
return sprintf(buf, "%d\n", nd_region->ro);
}
static ssize_t read_only_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t len)
{
bool ro;
int rc = strtobool(buf, &ro);
struct nd_region *nd_region = to_nd_region(dev);
if (rc)
return rc;
nd_region->ro = ro;
return len;
}
static DEVICE_ATTR_RW(read_only);
static struct attribute *nd_region_attributes[] = {
&dev_attr_size.attr,
&dev_attr_nstype.attr,
&dev_attr_mappings.attr,
&dev_attr_btt_seed.attr,
&dev_attr_read_only.attr,
&dev_attr_set_cookie.attr,
&dev_attr_available_size.attr,
&dev_attr_namespace_seed.attr,
&dev_attr_init_namespaces.attr,
NULL,
};
static umode_t region_visible(struct kobject *kobj, struct attribute *a, int n)
{
struct device *dev = container_of(kobj, typeof(*dev), kobj);
struct nd_region *nd_region = to_nd_region(dev);
struct nd_interleave_set *nd_set = nd_region->nd_set;
int type = nd_region_to_nstype(nd_region);
if (a != &dev_attr_set_cookie.attr
&& a != &dev_attr_available_size.attr)
return a->mode;
if ((type == ND_DEVICE_NAMESPACE_PMEM
|| type == ND_DEVICE_NAMESPACE_BLK)
&& a == &dev_attr_available_size.attr)
return a->mode;
else if (is_nd_pmem(dev) && nd_set)
return a->mode;
return 0;
}
struct attribute_group nd_region_attribute_group = {
.attrs = nd_region_attributes,
.is_visible = region_visible,
};
EXPORT_SYMBOL_GPL(nd_region_attribute_group);
u64 nd_region_interleave_set_cookie(struct nd_region *nd_region)
{
struct nd_interleave_set *nd_set = nd_region->nd_set;
if (nd_set)
return nd_set->cookie;
return 0;
}
/*
* Upon successful probe/remove, take/release a reference on the
* associated interleave set (if present), and plant new btt + namespace
* seeds. Also, on the removal of a BLK region, notify the provider to
* disable the region.
*/
static void nd_region_notify_driver_action(struct nvdimm_bus *nvdimm_bus,
struct device *dev, bool probe)
{
struct nd_region *nd_region;
if (!probe && (is_nd_pmem(dev) || is_nd_blk(dev))) {
int i;
nd_region = to_nd_region(dev);
for (i = 0; i < nd_region->ndr_mappings; i++) {
struct nd_mapping *nd_mapping = &nd_region->mapping[i];
struct nvdimm_drvdata *ndd = nd_mapping->ndd;
struct nvdimm *nvdimm = nd_mapping->nvdimm;
kfree(nd_mapping->labels);
nd_mapping->labels = NULL;
put_ndd(ndd);
nd_mapping->ndd = NULL;
if (ndd)
atomic_dec(&nvdimm->busy);
}
if (is_nd_pmem(dev))
return;
to_nd_blk_region(dev)->disable(nvdimm_bus, dev);
}
if (dev->parent && is_nd_blk(dev->parent) && probe) {
nd_region = to_nd_region(dev->parent);
nvdimm_bus_lock(dev);
if (nd_region->ns_seed == dev)
nd_region_create_blk_seed(nd_region);
nvdimm_bus_unlock(dev);
}
if (is_nd_btt(dev) && probe) {
nd_region = to_nd_region(dev->parent);
nvdimm_bus_lock(dev);
if (nd_region->btt_seed == dev)
nd_region_create_btt_seed(nd_region);
nvdimm_bus_unlock(dev);
}
}
void nd_region_probe_success(struct nvdimm_bus *nvdimm_bus, struct device *dev)
{
nd_region_notify_driver_action(nvdimm_bus, dev, true);
}
void nd_region_disable(struct nvdimm_bus *nvdimm_bus, struct device *dev)
{
nd_region_notify_driver_action(nvdimm_bus, dev, false);
}
static ssize_t mappingN(struct device *dev, char *buf, int n)
{
struct nd_region *nd_region = to_nd_region(dev);
struct nd_mapping *nd_mapping;
struct nvdimm *nvdimm;
if (n >= nd_region->ndr_mappings)
return -ENXIO;
nd_mapping = &nd_region->mapping[n];
nvdimm = nd_mapping->nvdimm;
return sprintf(buf, "%s,%llu,%llu\n", dev_name(&nvdimm->dev),
nd_mapping->start, nd_mapping->size);
}
#define REGION_MAPPING(idx) \
static ssize_t mapping##idx##_show(struct device *dev, \
struct device_attribute *attr, char *buf) \
{ \
return mappingN(dev, buf, idx); \
} \
static DEVICE_ATTR_RO(mapping##idx)
/*
* 32 should be enough for a while, even in the presence of socket
* interleave a 32-way interleave set is a degenerate case.
*/
REGION_MAPPING(0);
REGION_MAPPING(1);
REGION_MAPPING(2);
REGION_MAPPING(3);
REGION_MAPPING(4);
REGION_MAPPING(5);
REGION_MAPPING(6);
REGION_MAPPING(7);
REGION_MAPPING(8);
REGION_MAPPING(9);
REGION_MAPPING(10);
REGION_MAPPING(11);
REGION_MAPPING(12);
REGION_MAPPING(13);
REGION_MAPPING(14);
REGION_MAPPING(15);
REGION_MAPPING(16);
REGION_MAPPING(17);
REGION_MAPPING(18);
REGION_MAPPING(19);
REGION_MAPPING(20);
REGION_MAPPING(21);
REGION_MAPPING(22);
REGION_MAPPING(23);
REGION_MAPPING(24);
REGION_MAPPING(25);
REGION_MAPPING(26);
REGION_MAPPING(27);
REGION_MAPPING(28);
REGION_MAPPING(29);
REGION_MAPPING(30);
REGION_MAPPING(31);
static umode_t mapping_visible(struct kobject *kobj, struct attribute *a, int n)
{
struct device *dev = container_of(kobj, struct device, kobj);
struct nd_region *nd_region = to_nd_region(dev);
if (n < nd_region->ndr_mappings)
return a->mode;
return 0;
}
static struct attribute *mapping_attributes[] = {
&dev_attr_mapping0.attr,
&dev_attr_mapping1.attr,
&dev_attr_mapping2.attr,
&dev_attr_mapping3.attr,
&dev_attr_mapping4.attr,
&dev_attr_mapping5.attr,
&dev_attr_mapping6.attr,
&dev_attr_mapping7.attr,
&dev_attr_mapping8.attr,
&dev_attr_mapping9.attr,
&dev_attr_mapping10.attr,
&dev_attr_mapping11.attr,
&dev_attr_mapping12.attr,
&dev_attr_mapping13.attr,
&dev_attr_mapping14.attr,
&dev_attr_mapping15.attr,
&dev_attr_mapping16.attr,
&dev_attr_mapping17.attr,
&dev_attr_mapping18.attr,
&dev_attr_mapping19.attr,
&dev_attr_mapping20.attr,
&dev_attr_mapping21.attr,
&dev_attr_mapping22.attr,
&dev_attr_mapping23.attr,
&dev_attr_mapping24.attr,
&dev_attr_mapping25.attr,
&dev_attr_mapping26.attr,
&dev_attr_mapping27.attr,
&dev_attr_mapping28.attr,
&dev_attr_mapping29.attr,
&dev_attr_mapping30.attr,
&dev_attr_mapping31.attr,
NULL,
};
struct attribute_group nd_mapping_attribute_group = {
.is_visible = mapping_visible,
.attrs = mapping_attributes,
};
EXPORT_SYMBOL_GPL(nd_mapping_attribute_group);
int nd_blk_region_init(struct nd_region *nd_region)
{
struct device *dev = &nd_region->dev;
struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
if (!is_nd_blk(dev))
return 0;
if (nd_region->ndr_mappings < 1) {
dev_err(dev, "invalid BLK region\n");
return -ENXIO;
}
return to_nd_blk_region(dev)->enable(nvdimm_bus, dev);
}
/**
* nd_region_acquire_lane - allocate and lock a lane
* @nd_region: region id and number of lanes possible
*
* A lane correlates to a BLK-data-window and/or a log slot in the BTT.
* We optimize for the common case where there are 256 lanes, one
* per-cpu. For larger systems we need to lock to share lanes. For now
* this implementation assumes the cost of maintaining an allocator for
* free lanes is on the order of the lock hold time, so it implements a
* static lane = cpu % num_lanes mapping.
*
* In the case of a BTT instance on top of a BLK namespace a lane may be
* acquired recursively. We lock on the first instance.
*
* In the case of a BTT instance on top of PMEM, we only acquire a lane
* for the BTT metadata updates.
*/
unsigned int nd_region_acquire_lane(struct nd_region *nd_region)
{
unsigned int cpu, lane;
cpu = get_cpu();
if (nd_region->num_lanes < nr_cpu_ids) {
struct nd_percpu_lane *ndl_lock, *ndl_count;
lane = cpu % nd_region->num_lanes;
ndl_count = per_cpu_ptr(nd_region->lane, cpu);
ndl_lock = per_cpu_ptr(nd_region->lane, lane);
if (ndl_count->count++ == 0)
spin_lock(&ndl_lock->lock);
} else
lane = cpu;
return lane;
}
EXPORT_SYMBOL(nd_region_acquire_lane);
void nd_region_release_lane(struct nd_region *nd_region, unsigned int lane)
{
if (nd_region->num_lanes < nr_cpu_ids) {
unsigned int cpu = get_cpu();
struct nd_percpu_lane *ndl_lock, *ndl_count;
ndl_count = per_cpu_ptr(nd_region->lane, cpu);
ndl_lock = per_cpu_ptr(nd_region->lane, lane);
if (--ndl_count->count == 0)
spin_unlock(&ndl_lock->lock);
put_cpu();
}
put_cpu();
}
EXPORT_SYMBOL(nd_region_release_lane);
static struct nd_region *nd_region_create(struct nvdimm_bus *nvdimm_bus,
struct nd_region_desc *ndr_desc, struct device_type *dev_type,
const char *caller)
{
struct nd_region *nd_region;
struct device *dev;
void *region_buf;
unsigned int i;
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;
if ((nd_mapping->start | nd_mapping->size) % SZ_4K) {
dev_err(&nvdimm_bus->dev, "%s: %s mapping%d is not 4K aligned\n",
caller, dev_name(&nvdimm->dev), i);
return NULL;
}
if (nvdimm->flags & NDD_UNARMED)
ro = 1;
}
if (dev_type == &nd_blk_device_type) {
struct nd_blk_region_desc *ndbr_desc;
struct nd_blk_region *ndbr;
ndbr_desc = to_blk_region_desc(ndr_desc);
ndbr = kzalloc(sizeof(*ndbr) + sizeof(struct nd_mapping)
* ndr_desc->num_mappings,
GFP_KERNEL);
if (ndbr) {
nd_region = &ndbr->nd_region;
ndbr->enable = ndbr_desc->enable;
ndbr->disable = ndbr_desc->disable;
ndbr->do_io = ndbr_desc->do_io;
}
region_buf = ndbr;
} else {
nd_region = kzalloc(sizeof(struct nd_region)
+ sizeof(struct nd_mapping)
* ndr_desc->num_mappings,
GFP_KERNEL);
region_buf = nd_region;
}
if (!region_buf)
return NULL;
nd_region->id = ida_simple_get(&region_ida, 0, 0, GFP_KERNEL);
if (nd_region->id < 0)
goto err_id;
nd_region->lane = alloc_percpu(struct nd_percpu_lane);
if (!nd_region->lane)
goto err_percpu;
for (i = 0; i < nr_cpu_ids; i++) {
struct nd_percpu_lane *ndl;
ndl = per_cpu_ptr(nd_region->lane, i);
spin_lock_init(&ndl->lock);
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;
get_device(&nvdimm->dev);
}
nd_region->ndr_mappings = ndr_desc->num_mappings;
nd_region->provider_data = ndr_desc->provider_data;
nd_region->nd_set = ndr_desc->nd_set;
nd_region->num_lanes = ndr_desc->num_lanes;
nd_region->ro = ro;
nd_region->numa_node = ndr_desc->numa_node;
ida_init(&nd_region->ns_ida);
ida_init(&nd_region->btt_ida);
dev = &nd_region->dev;
dev_set_name(dev, "region%d", nd_region->id);
dev->parent = &nvdimm_bus->dev;
dev->type = dev_type;
dev->groups = ndr_desc->attr_groups;
nd_region->ndr_size = resource_size(ndr_desc->res);
nd_region->ndr_start = ndr_desc->res->start;
nd_device_register(dev);
return nd_region;
err_percpu:
ida_simple_remove(&region_ida, nd_region->id);
err_id:
kfree(region_buf);
return NULL;
}
struct nd_region *nvdimm_pmem_region_create(struct nvdimm_bus *nvdimm_bus,
struct nd_region_desc *ndr_desc)
{
ndr_desc->num_lanes = ND_MAX_LANES;
return nd_region_create(nvdimm_bus, ndr_desc, &nd_pmem_device_type,
__func__);
}
EXPORT_SYMBOL_GPL(nvdimm_pmem_region_create);
struct nd_region *nvdimm_blk_region_create(struct nvdimm_bus *nvdimm_bus,
struct nd_region_desc *ndr_desc)
{
if (ndr_desc->num_mappings > 1)
return NULL;
ndr_desc->num_lanes = min(ndr_desc->num_lanes, ND_MAX_LANES);
return nd_region_create(nvdimm_bus, ndr_desc, &nd_blk_device_type,
__func__);
}
EXPORT_SYMBOL_GPL(nvdimm_blk_region_create);
struct nd_region *nvdimm_volatile_region_create(struct nvdimm_bus *nvdimm_bus,
struct nd_region_desc *ndr_desc)
{
ndr_desc->num_lanes = ND_MAX_LANES;
return nd_region_create(nvdimm_bus, ndr_desc, &nd_volatile_device_type,
__func__);
}
EXPORT_SYMBOL_GPL(nvdimm_volatile_region_create);