[linux-2.6-block.git] / drivers / nvdimm / dimm_devs.c

/*
 * 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.
 */
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/vmalloc.h>
#include <linux/device.h>
#include <linux/ndctl.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include "nd-core.h"
#include "label.h"
#include "pmem.h"
#include "nd.h"

static DEFINE_IDA(dimm_ida);

/*
 * Retrieve bus and dimm handle and return if this bus supports
 * get_config_data commands
 */
int nvdimm_check_config_data(struct device *dev)
{
	struct nvdimm *nvdimm = to_nvdimm(dev);

	if (!nvdimm->cmd_mask ||
	    !test_bit(ND_CMD_GET_CONFIG_DATA, &nvdimm->cmd_mask)) {
		if (test_bit(NDD_ALIASING, &nvdimm->flags))
			return -ENXIO;
		else
			return -ENOTTY;
	}

	return 0;
}

static int validate_dimm(struct nvdimm_drvdata *ndd)
{
	int rc;

	if (!ndd)
		return -EINVAL;

	rc = nvdimm_check_config_data(ndd->dev);
	if (rc)
		dev_dbg(ndd->dev, "%pf: %s error: %d\n",
				__builtin_return_address(0), __func__, rc);
	return rc;
}

/**
 * nvdimm_init_nsarea - determine the geometry of a dimm's namespace area
 * @nvdimm: dimm to initialize
 */
int nvdimm_init_nsarea(struct nvdimm_drvdata *ndd)
{
	struct nd_cmd_get_config_size *cmd = &ndd->nsarea;
	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(ndd->dev);
	struct nvdimm_bus_descriptor *nd_desc;
	int rc = validate_dimm(ndd);
	int cmd_rc = 0;

	if (rc)
		return rc;

	if (cmd->config_size)
		return 0; /* already valid */

	memset(cmd, 0, sizeof(*cmd));
	nd_desc = nvdimm_bus->nd_desc;
	rc = nd_desc->ndctl(nd_desc, to_nvdimm(ndd->dev),
			ND_CMD_GET_CONFIG_SIZE, cmd, sizeof(*cmd), &cmd_rc);
	if (rc < 0)
		return rc;
	return cmd_rc;
}

int nvdimm_init_config_data(struct nvdimm_drvdata *ndd)
{
	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(ndd->dev);
	struct nd_cmd_get_config_data_hdr *cmd;
	struct nvdimm_bus_descriptor *nd_desc;
	int rc = validate_dimm(ndd);
	u32 max_cmd_size, config_size;
	size_t offset;

	if (rc)
		return rc;

	if (ndd->data)
		return 0;

	if (ndd->nsarea.status || ndd->nsarea.max_xfer == 0
			|| ndd->nsarea.config_size < ND_LABEL_MIN_SIZE) {
		dev_dbg(ndd->dev, "failed to init config data area: (%d:%d)\n",
				ndd->nsarea.max_xfer, ndd->nsarea.config_size);
		return -ENXIO;
	}

	ndd->data = kvmalloc(ndd->nsarea.config_size, GFP_KERNEL);
	if (!ndd->data)
		return -ENOMEM;

	max_cmd_size = min_t(u32, PAGE_SIZE, ndd->nsarea.max_xfer);
	cmd = kzalloc(max_cmd_size + sizeof(*cmd), GFP_KERNEL);
	if (!cmd)
		return -ENOMEM;

	nd_desc = nvdimm_bus->nd_desc;
	for (config_size = ndd->nsarea.config_size, offset = 0;
			config_size; config_size -= cmd->in_length,
			offset += cmd->in_length) {
		cmd->in_length = min(config_size, max_cmd_size);
		cmd->in_offset = offset;
		rc = nd_desc->ndctl(nd_desc, to_nvdimm(ndd->dev),
				ND_CMD_GET_CONFIG_DATA, cmd,
				cmd->in_length + sizeof(*cmd), NULL);
		if (rc || cmd->status) {
			rc = -ENXIO;
			break;
		}
		memcpy(ndd->data + offset, cmd->out_buf, cmd->in_length);
	}
	dev_dbg(ndd->dev, "%s: len: %zu rc: %d\n", __func__, offset, rc);
	kfree(cmd);

	return rc;
}

int nvdimm_set_config_data(struct nvdimm_drvdata *ndd, size_t offset,
		void *buf, size_t len)
{
	int rc = validate_dimm(ndd);
	size_t max_cmd_size, buf_offset;
	struct nd_cmd_set_config_hdr *cmd;
	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(ndd->dev);
	struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;

	if (rc)
		return rc;

	if (!ndd->data)
		return -ENXIO;

	if (offset + len > ndd->nsarea.config_size)
		return -ENXIO;

	max_cmd_size = min_t(u32, PAGE_SIZE, len);
	max_cmd_size = min_t(u32, max_cmd_size, ndd->nsarea.max_xfer);
	cmd = kzalloc(max_cmd_size + sizeof(*cmd) + sizeof(u32), GFP_KERNEL);
	if (!cmd)
		return -ENOMEM;

	for (buf_offset = 0; len; len -= cmd->in_length,
			buf_offset += cmd->in_length) {
		size_t cmd_size;
		u32 *status;

		cmd->in_offset = offset + buf_offset;
		cmd->in_length = min(max_cmd_size, len);
		memcpy(cmd->in_buf, buf + buf_offset, cmd->in_length);

		/* status is output in the last 4-bytes of the command buffer */
		cmd_size = sizeof(*cmd) + cmd->in_length + sizeof(u32);
		status = ((void *) cmd) + cmd_size - sizeof(u32);

		rc = nd_desc->ndctl(nd_desc, to_nvdimm(ndd->dev),
				ND_CMD_SET_CONFIG_DATA, cmd, cmd_size, NULL);
		if (rc || *status) {
			rc = rc ? rc : -ENXIO;
			break;
		}
	}
	kfree(cmd);

	return rc;
}

void nvdimm_set_aliasing(struct device *dev)
{
	struct nvdimm *nvdimm = to_nvdimm(dev);

	set_bit(NDD_ALIASING, &nvdimm->flags);
}

void nvdimm_set_locked(struct device *dev)
{
	struct nvdimm *nvdimm = to_nvdimm(dev);

	set_bit(NDD_LOCKED, &nvdimm->flags);
}

void nvdimm_clear_locked(struct device *dev)
{
	struct nvdimm *nvdimm = to_nvdimm(dev);

	clear_bit(NDD_LOCKED, &nvdimm->flags);
}

static void nvdimm_release(struct device *dev)
{
	struct nvdimm *nvdimm = to_nvdimm(dev);

	ida_simple_remove(&dimm_ida, nvdimm->id);
	kfree(nvdimm);
}

static struct device_type nvdimm_device_type = {
	.name = "nvdimm",
	.release = nvdimm_release,
};

bool is_nvdimm(struct device *dev)
{
	return dev->type == &nvdimm_device_type;
}

struct nvdimm *to_nvdimm(struct device *dev)
{
	struct nvdimm *nvdimm = container_of(dev, struct nvdimm, dev);

	WARN_ON(!is_nvdimm(dev));
	return nvdimm;
}
EXPORT_SYMBOL_GPL(to_nvdimm);

struct nvdimm *nd_blk_region_to_dimm(struct nd_blk_region *ndbr)
{
	struct nd_region *nd_region = &ndbr->nd_region;
	struct nd_mapping *nd_mapping = &nd_region->mapping[0];

	return nd_mapping->nvdimm;
}
EXPORT_SYMBOL_GPL(nd_blk_region_to_dimm);

unsigned long nd_blk_memremap_flags(struct nd_blk_region *ndbr)
{
	/* pmem mapping properties are private to libnvdimm */
	return ARCH_MEMREMAP_PMEM;
}
EXPORT_SYMBOL_GPL(nd_blk_memremap_flags);

struct nvdimm_drvdata *to_ndd(struct nd_mapping *nd_mapping)
{
	struct nvdimm *nvdimm = nd_mapping->nvdimm;

	WARN_ON_ONCE(!is_nvdimm_bus_locked(&nvdimm->dev));

	return dev_get_drvdata(&nvdimm->dev);
}
EXPORT_SYMBOL(to_ndd);

void nvdimm_drvdata_release(struct kref *kref)
{
	struct nvdimm_drvdata *ndd = container_of(kref, typeof(*ndd), kref);
	struct device *dev = ndd->dev;
	struct resource *res, *_r;

	dev_dbg(dev, "%s\n", __func__);

	nvdimm_bus_lock(dev);
	for_each_dpa_resource_safe(ndd, res, _r)
		nvdimm_free_dpa(ndd, res);
	nvdimm_bus_unlock(dev);

	kvfree(ndd->data);
	kfree(ndd);
	put_device(dev);
}

void get_ndd(struct nvdimm_drvdata *ndd)
{
	kref_get(&ndd->kref);
}

void put_ndd(struct nvdimm_drvdata *ndd)
{
	if (ndd)
		kref_put(&ndd->kref, nvdimm_drvdata_release);
}

const char *nvdimm_name(struct nvdimm *nvdimm)
{
	return dev_name(&nvdimm->dev);
}
EXPORT_SYMBOL_GPL(nvdimm_name);

struct kobject *nvdimm_kobj(struct nvdimm *nvdimm)
{
	return &nvdimm->dev.kobj;
}
EXPORT_SYMBOL_GPL(nvdimm_kobj);

unsigned long nvdimm_cmd_mask(struct nvdimm *nvdimm)
{
	return nvdimm->cmd_mask;
}
EXPORT_SYMBOL_GPL(nvdimm_cmd_mask);

void *nvdimm_provider_data(struct nvdimm *nvdimm)
{
	if (nvdimm)
		return nvdimm->provider_data;
	return NULL;
}
EXPORT_SYMBOL_GPL(nvdimm_provider_data);

static ssize_t commands_show(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	struct nvdimm *nvdimm = to_nvdimm(dev);
	int cmd, len = 0;

	if (!nvdimm->cmd_mask)
		return sprintf(buf, "\n");

	for_each_set_bit(cmd, &nvdimm->cmd_mask, BITS_PER_LONG)
		len += sprintf(buf + len, "%s ", nvdimm_cmd_name(cmd));
	len += sprintf(buf + len, "\n");
	return len;
}
static DEVICE_ATTR_RO(commands);

static ssize_t flags_show(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	struct nvdimm *nvdimm = to_nvdimm(dev);

	return sprintf(buf, "%s%s\n",
			test_bit(NDD_ALIASING, &nvdimm->flags) ? "alias " : "",
			test_bit(NDD_LOCKED, &nvdimm->flags) ? "lock " : "");
}
static DEVICE_ATTR_RO(flags);

static ssize_t state_show(struct device *dev, struct device_attribute *attr,
		char *buf)
{
	struct nvdimm *nvdimm = to_nvdimm(dev);

	/*
	 * The state may be in the process of changing, userspace should
	 * quiesce probing if it wants a static answer
	 */
	nvdimm_bus_lock(dev);
	nvdimm_bus_unlock(dev);
	return sprintf(buf, "%s\n", atomic_read(&nvdimm->busy)
			? "active" : "idle");
}
static DEVICE_ATTR_RO(state);

static ssize_t available_slots_show(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	struct nvdimm_drvdata *ndd = dev_get_drvdata(dev);
	ssize_t rc;
	u32 nfree;

	if (!ndd)
		return -ENXIO;

	nvdimm_bus_lock(dev);
	nfree = nd_label_nfree(ndd);
	if (nfree - 1 > nfree) {
		dev_WARN_ONCE(dev, 1, "we ate our last label?\n");
		nfree = 0;
	} else
		nfree--;
	rc = sprintf(buf, "%d\n", nfree);
	nvdimm_bus_unlock(dev);
	return rc;
}
static DEVICE_ATTR_RO(available_slots);

static struct attribute *nvdimm_attributes[] = {
	&dev_attr_state.attr,
	&dev_attr_flags.attr,
	&dev_attr_commands.attr,
	&dev_attr_available_slots.attr,
	NULL,
};

struct attribute_group nvdimm_attribute_group = {
	.attrs = nvdimm_attributes,
};
EXPORT_SYMBOL_GPL(nvdimm_attribute_group);

struct nvdimm *nvdimm_create(struct nvdimm_bus *nvdimm_bus, void *provider_data,
		const struct attribute_group **groups, unsigned long flags,
		unsigned long cmd_mask, int num_flush,
		struct resource *flush_wpq)
{
	struct nvdimm *nvdimm = kzalloc(sizeof(*nvdimm), GFP_KERNEL);
	struct device *dev;

	if (!nvdimm)
		return NULL;

	nvdimm->id = ida_simple_get(&dimm_ida, 0, 0, GFP_KERNEL);
	if (nvdimm->id < 0) {
		kfree(nvdimm);
		return NULL;
	}
	nvdimm->provider_data = provider_data;
	nvdimm->flags = flags;
	nvdimm->cmd_mask = cmd_mask;
	nvdimm->num_flush = num_flush;
	nvdimm->flush_wpq = flush_wpq;
	atomic_set(&nvdimm->busy, 0);
	dev = &nvdimm->dev;
	dev_set_name(dev, "nmem%d", nvdimm->id);
	dev->parent = &nvdimm_bus->dev;
	dev->type = &nvdimm_device_type;
	dev->devt = MKDEV(nvdimm_major, nvdimm->id);
	dev->groups = groups;
	nd_device_register(dev);

	return nvdimm;
}
EXPORT_SYMBOL_GPL(nvdimm_create);

int alias_dpa_busy(struct device *dev, void *data)
{
	resource_size_t map_end, blk_start, new;
	struct blk_alloc_info *info = data;
	struct nd_mapping *nd_mapping;
	struct nd_region *nd_region;
	struct nvdimm_drvdata *ndd;
	struct resource *res;
	int i;

	if (!is_memory(dev))
		return 0;

	nd_region = to_nd_region(dev);
	for (i = 0; i < nd_region->ndr_mappings; i++) {
		nd_mapping  = &nd_region->mapping[i];
		if (nd_mapping->nvdimm == info->nd_mapping->nvdimm)
			break;
	}

	if (i >= nd_region->ndr_mappings)
		return 0;

	ndd = to_ndd(nd_mapping);
	map_end = nd_mapping->start + nd_mapping->size - 1;
	blk_start = nd_mapping->start;

	/*
	 * In the allocation case ->res is set to free space that we are
	 * looking to validate against PMEM aliasing collision rules
	 * (i.e. BLK is allocated after all aliased PMEM).
	 */
	if (info->res) {
		if (info->res->start >= nd_mapping->start
				&& info->res->start < map_end)
			/* pass */;
		else
			return 0;
	}

 retry:
	/*
	 * Find the free dpa from the end of the last pmem allocation to
	 * the end of the interleave-set mapping.
	 */
	for_each_dpa_resource(ndd, res) {
		if (strncmp(res->name, "pmem", 4) != 0)
			continue;
		if ((res->start >= blk_start && res->start < map_end)
				|| (res->end >= blk_start
					&& res->end <= map_end)) {
			new = max(blk_start, min(map_end + 1, res->end + 1));
			if (new != blk_start) {
				blk_start = new;
				goto retry;
			}
		}
	}

	/* update the free space range with the probed blk_start */
	if (info->res && blk_start > info->res->start) {
		info->res->start = max(info->res->start, blk_start);
		if (info->res->start > info->res->end)
			info->res->end = info->res->start - 1;
		return 1;
	}

	info->available -= blk_start - nd_mapping->start;

	return 0;
}

/**
 * nd_blk_available_dpa - account the unused dpa of BLK region
 * @nd_mapping: container of dpa-resource-root + labels
 *
 * Unlike PMEM, BLK namespaces can occupy discontiguous DPA ranges, but
 * we arrange for them to never start at an lower dpa than the last
 * PMEM allocation in an aliased region.
 */
resource_size_t nd_blk_available_dpa(struct nd_region *nd_region)
{
	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&nd_region->dev);
	struct nd_mapping *nd_mapping = &nd_region->mapping[0];
	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
	struct blk_alloc_info info = {
		.nd_mapping = nd_mapping,
		.available = nd_mapping->size,
		.res = NULL,
	};
	struct resource *res;

	if (!ndd)
		return 0;

	device_for_each_child(&nvdimm_bus->dev, &info, alias_dpa_busy);

	/* now account for busy blk allocations in unaliased dpa */
	for_each_dpa_resource(ndd, res) {
		if (strncmp(res->name, "blk", 3) != 0)
			continue;
		info.available -= resource_size(res);
	}

	return info.available;
}

/**
 * nd_pmem_available_dpa - for the given dimm+region account unallocated dpa
 * @nd_mapping: container of dpa-resource-root + labels
 * @nd_region: constrain available space check to this reference region
 * @overlap: calculate available space assuming this level of overlap
 *
 * Validate that a PMEM label, if present, aligns with the start of an
 * interleave set and truncate the available size at the lowest BLK
 * overlap point.
 *
 * The expectation is that this routine is called multiple times as it
 * probes for the largest BLK encroachment for any single member DIMM of
 * the interleave set.  Once that value is determined the PMEM-limit for
 * the set can be established.
 */
resource_size_t nd_pmem_available_dpa(struct nd_region *nd_region,
		struct nd_mapping *nd_mapping, resource_size_t *overlap)
{
	resource_size_t map_start, map_end, busy = 0, available, blk_start;
	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
	struct resource *res;
	const char *reason;

	if (!ndd)
		return 0;

	map_start = nd_mapping->start;
	map_end = map_start + nd_mapping->size - 1;
	blk_start = max(map_start, map_end + 1 - *overlap);
	for_each_dpa_resource(ndd, res) {
		if (res->start >= map_start && res->start < map_end) {
			if (strncmp(res->name, "blk", 3) == 0)
				blk_start = min(blk_start,
						max(map_start, res->start));
			else if (res->end > map_end) {
				reason = "misaligned to iset";
				goto err;
			} else
				busy += resource_size(res);
		} else if (res->end >= map_start && res->end <= map_end) {
			if (strncmp(res->name, "blk", 3) == 0) {
				/*
				 * If a BLK allocation overlaps the start of
				 * PMEM the entire interleave set may now only
				 * be used for BLK.
				 */
				blk_start = map_start;
			} else
				busy += resource_size(res);
		} else if (map_start > res->start && map_start < res->end) {
			/* total eclipse of the mapping */
			busy += nd_mapping->size;
			blk_start = map_start;
		}
	}

	*overlap = map_end + 1 - blk_start;
	available = blk_start - map_start;
	if (busy < available)
		return available - busy;
	return 0;

 err:
	nd_dbg_dpa(nd_region, ndd, res, "%s\n", reason);
	return 0;
}

void nvdimm_free_dpa(struct nvdimm_drvdata *ndd, struct resource *res)
{
	WARN_ON_ONCE(!is_nvdimm_bus_locked(ndd->dev));
	kfree(res->name);
	__release_region(&ndd->dpa, res->start, resource_size(res));
}

struct resource *nvdimm_allocate_dpa(struct nvdimm_drvdata *ndd,
		struct nd_label_id *label_id, resource_size_t start,
		resource_size_t n)
{
	char *name = kmemdup(label_id, sizeof(*label_id), GFP_KERNEL);
	struct resource *res;

	if (!name)
		return NULL;

	WARN_ON_ONCE(!is_nvdimm_bus_locked(ndd->dev));
	res = __request_region(&ndd->dpa, start, n, name, 0);
	if (!res)
		kfree(name);
	return res;
}

/**
 * nvdimm_allocated_dpa - sum up the dpa currently allocated to this label_id
 * @nvdimm: container of dpa-resource-root + labels
 * @label_id: dpa resource name of the form {pmem|blk}-<human readable uuid>
 */
resource_size_t nvdimm_allocated_dpa(struct nvdimm_drvdata *ndd,
		struct nd_label_id *label_id)
{
	resource_size_t allocated = 0;
	struct resource *res;

	for_each_dpa_resource(ndd, res)
		if (strcmp(res->name, label_id->id) == 0)
			allocated += resource_size(res);

	return allocated;
}

static int count_dimms(struct device *dev, void *c)
{
	int *count = c;

	if (is_nvdimm(dev))
		(*count)++;
	return 0;
}

int nvdimm_bus_check_dimm_count(struct nvdimm_bus *nvdimm_bus, int dimm_count)
{
	int count = 0;
	/* Flush any possible dimm registration failures */
	nd_synchronize();

	device_for_each_child(&nvdimm_bus->dev, &count, count_dimms);
	dev_dbg(&nvdimm_bus->dev, "%s: count: %d\n", __func__, count);
	if (count != dimm_count)
		return -ENXIO;
	return 0;
}
EXPORT_SYMBOL_GPL(nvdimm_bus_check_dimm_count);

void __exit nvdimm_devs_exit(void)
{
	ida_destroy(&dimm_ida);
}
Commit	Line	Data
e6dfb2de DW	1	/*
	2	* Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of version 2 of the GNU General Public License as
	6	* published by the Free Software Foundation.
	7	*
	8	* This program is distributed in the hope that it will be useful, but
	9	* WITHOUT ANY WARRANTY; without even the implied warranty of
	10	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	11	* General Public License for more details.
	12	*/
	13	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
4d88a97a	14	#include <linux/vmalloc.h>
e6dfb2de	15	#include <linux/device.h>
62232e45	16	#include <linux/ndctl.h>
e6dfb2de DW	17	#include <linux/slab.h>
	18	#include <linux/io.h>
	19	#include <linux/fs.h>
	20	#include <linux/mm.h>
	21	#include "nd-core.h"
0ba1c634	22	#include "label.h"
ca6a4657	23	#include "pmem.h"
4d88a97a	24	#include "nd.h"
e6dfb2de DW	25
	26	static DEFINE_IDA(dimm_ida);
	27
4d88a97a DW	28	/*
	29	* Retrieve bus and dimm handle and return if this bus supports
	30	* get_config_data commands
	31	*/
aee65987	32	int nvdimm_check_config_data(struct device *dev)
4d88a97a	33	{
aee65987	34	struct nvdimm *nvdimm = to_nvdimm(dev);
4d88a97a	35
aee65987 TK	36	if (!nvdimm->cmd_mask \|\|
aee65987 TK	37	!test_bit(ND_CMD_GET_CONFIG_DATA, &nvdimm->cmd_mask)) {
8f078b38	38	if (test_bit(NDD_ALIASING, &nvdimm->flags))
aee65987 TK	39	return -ENXIO;
	40	else
	41	return -ENOTTY;
	42	}
4d88a97a DW	43
	44	return 0;
	45	}
	46
	47	static int validate_dimm(struct nvdimm_drvdata *ndd)
	48	{
aee65987	49	int rc;
4d88a97a	50
aee65987 TK	51	if (!ndd)
	52	return -EINVAL;
	53
	54	rc = nvdimm_check_config_data(ndd->dev);
	55	if (rc)
4d88a97a DW	56	dev_dbg(ndd->dev, "%pf: %s error: %d\n",
	57	__builtin_return_address(0), __func__, rc);
	58	return rc;
	59	}
	60
	61	/**
	62	* nvdimm_init_nsarea - determine the geometry of a dimm's namespace area
	63	* @nvdimm: dimm to initialize
	64	*/
	65	int nvdimm_init_nsarea(struct nvdimm_drvdata *ndd)
	66	{
	67	struct nd_cmd_get_config_size *cmd = &ndd->nsarea;
	68	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(ndd->dev);
	69	struct nvdimm_bus_descriptor *nd_desc;
	70	int rc = validate_dimm(ndd);
9d62ed96	71	int cmd_rc = 0;
4d88a97a DW	72
	73	if (rc)
	74	return rc;
	75
	76	if (cmd->config_size)
	77	return 0; /* already valid */
	78
	79	memset(cmd, 0, sizeof(*cmd));
	80	nd_desc = nvdimm_bus->nd_desc;
9d62ed96 DW	81	rc = nd_desc->ndctl(nd_desc, to_nvdimm(ndd->dev),
	82	ND_CMD_GET_CONFIG_SIZE, cmd, sizeof(*cmd), &cmd_rc);
	83	if (rc < 0)
	84	return rc;
	85	return cmd_rc;
4d88a97a DW	86	}
	87
	88	int nvdimm_init_config_data(struct nvdimm_drvdata *ndd)
	89	{
	90	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(ndd->dev);
	91	struct nd_cmd_get_config_data_hdr *cmd;
	92	struct nvdimm_bus_descriptor *nd_desc;
	93	int rc = validate_dimm(ndd);
	94	u32 max_cmd_size, config_size;
	95	size_t offset;
	96
	97	if (rc)
	98	return rc;
	99
	100	if (ndd->data)
	101	return 0;
	102
4a826c83 DW	103	if (ndd->nsarea.status \|\| ndd->nsarea.max_xfer == 0
	104	\|\| ndd->nsarea.config_size < ND_LABEL_MIN_SIZE) {
	105	dev_dbg(ndd->dev, "failed to init config data area: (%d:%d)\n",
	106	ndd->nsarea.max_xfer, ndd->nsarea.config_size);
4d88a97a	107	return -ENXIO;
4a826c83	108	}
4d88a97a	109
752ade68	110	ndd->data = kvmalloc(ndd->nsarea.config_size, GFP_KERNEL);
4d88a97a DW	111	if (!ndd->data)
	112	return -ENOMEM;
	113
	114	max_cmd_size = min_t(u32, PAGE_SIZE, ndd->nsarea.max_xfer);
	115	cmd = kzalloc(max_cmd_size + sizeof(*cmd), GFP_KERNEL);
	116	if (!cmd)
	117	return -ENOMEM;
	118
	119	nd_desc = nvdimm_bus->nd_desc;
	120	for (config_size = ndd->nsarea.config_size, offset = 0;
	121	config_size; config_size -= cmd->in_length,
	122	offset += cmd->in_length) {
	123	cmd->in_length = min(config_size, max_cmd_size);
	124	cmd->in_offset = offset;
	125	rc = nd_desc->ndctl(nd_desc, to_nvdimm(ndd->dev),
	126	ND_CMD_GET_CONFIG_DATA, cmd,
aef25338	127	cmd->in_length + sizeof(*cmd), NULL);
4d88a97a DW	128	if (rc \|\| cmd->status) {
	129	rc = -ENXIO;
	130	break;
	131	}
	132	memcpy(ndd->data + offset, cmd->out_buf, cmd->in_length);
	133	}
	134	dev_dbg(ndd->dev, "%s: len: %zu rc: %d\n", __func__, offset, rc);
	135	kfree(cmd);
	136
	137	return rc;
	138	}
	139
f524bf27 DW	140	int nvdimm_set_config_data(struct nvdimm_drvdata *ndd, size_t offset,
	141	void *buf, size_t len)
	142	{
	143	int rc = validate_dimm(ndd);
	144	size_t max_cmd_size, buf_offset;
	145	struct nd_cmd_set_config_hdr *cmd;
	146	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(ndd->dev);
	147	struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
	148
	149	if (rc)
	150	return rc;
	151
	152	if (!ndd->data)
	153	return -ENXIO;
	154
	155	if (offset + len > ndd->nsarea.config_size)
	156	return -ENXIO;
	157
	158	max_cmd_size = min_t(u32, PAGE_SIZE, len);
	159	max_cmd_size = min_t(u32, max_cmd_size, ndd->nsarea.max_xfer);
	160	cmd = kzalloc(max_cmd_size + sizeof(*cmd) + sizeof(u32), GFP_KERNEL);
	161	if (!cmd)
	162	return -ENOMEM;
	163
	164	for (buf_offset = 0; len; len -= cmd->in_length,
	165	buf_offset += cmd->in_length) {
	166	size_t cmd_size;
	167	u32 *status;
	168
	169	cmd->in_offset = offset + buf_offset;
	170	cmd->in_length = min(max_cmd_size, len);
	171	memcpy(cmd->in_buf, buf + buf_offset, cmd->in_length);
	172
	173	/* status is output in the last 4-bytes of the command buffer */
	174	cmd_size = sizeof(*cmd) + cmd->in_length + sizeof(u32);
	175	status = ((void *) cmd) + cmd_size - sizeof(u32);
	176
	177	rc = nd_desc->ndctl(nd_desc, to_nvdimm(ndd->dev),
aef25338	178	ND_CMD_SET_CONFIG_DATA, cmd, cmd_size, NULL);
f524bf27 DW	179	if (rc \|\| *status) {
	180	rc = rc ? rc : -ENXIO;
	181	break;
	182	}
	183	}
	184	kfree(cmd);
	185
	186	return rc;
	187	}
	188
42237e39 DW	189	void nvdimm_set_aliasing(struct device *dev)
	190	{
	191	struct nvdimm *nvdimm = to_nvdimm(dev);
	192
8f078b38 DW	193	set_bit(NDD_ALIASING, &nvdimm->flags);
	194	}
	195
	196	void nvdimm_set_locked(struct device *dev)
	197	{
	198	struct nvdimm *nvdimm = to_nvdimm(dev);
	199
	200	set_bit(NDD_LOCKED, &nvdimm->flags);
42237e39 DW	201	}
42237e39 DW	202
d34cb808 DW	203	void nvdimm_clear_locked(struct device *dev)
	204	{
	205	struct nvdimm *nvdimm = to_nvdimm(dev);
	206
	207	clear_bit(NDD_LOCKED, &nvdimm->flags);
	208	}
	209
e6dfb2de DW	210	static void nvdimm_release(struct device *dev)
	211	{
	212	struct nvdimm *nvdimm = to_nvdimm(dev);
	213
	214	ida_simple_remove(&dimm_ida, nvdimm->id);
	215	kfree(nvdimm);
	216	}
	217
	218	static struct device_type nvdimm_device_type = {
	219	.name = "nvdimm",
	220	.release = nvdimm_release,
	221	};
	222
62232e45	223	bool is_nvdimm(struct device *dev)
e6dfb2de DW	224	{
	225	return dev->type == &nvdimm_device_type;
	226	}
	227
	228	struct nvdimm to_nvdimm(struct device dev)
	229	{
	230	struct nvdimm *nvdimm = container_of(dev, struct nvdimm, dev);
	231
	232	WARN_ON(!is_nvdimm(dev));
	233	return nvdimm;
	234	}
	235	EXPORT_SYMBOL_GPL(to_nvdimm);
	236
047fc8a1 RZ	237	struct nvdimm nd_blk_region_to_dimm(struct nd_blk_region ndbr)
	238	{
	239	struct nd_region *nd_region = &ndbr->nd_region;
	240	struct nd_mapping *nd_mapping = &nd_region->mapping[0];
	241
	242	return nd_mapping->nvdimm;
	243	}
	244	EXPORT_SYMBOL_GPL(nd_blk_region_to_dimm);
	245
ca6a4657 DW	246	unsigned long nd_blk_memremap_flags(struct nd_blk_region *ndbr)
	247	{
	248	/* pmem mapping properties are private to libnvdimm */
	249	return ARCH_MEMREMAP_PMEM;
	250	}
	251	EXPORT_SYMBOL_GPL(nd_blk_memremap_flags);
	252
bf9bccc1 DW	253	struct nvdimm_drvdata to_ndd(struct nd_mapping nd_mapping)
	254	{
	255	struct nvdimm *nvdimm = nd_mapping->nvdimm;
	256
	257	WARN_ON_ONCE(!is_nvdimm_bus_locked(&nvdimm->dev));
	258
	259	return dev_get_drvdata(&nvdimm->dev);
	260	}
	261	EXPORT_SYMBOL(to_ndd);
	262
	263	void nvdimm_drvdata_release(struct kref *kref)
	264	{
	265	struct nvdimm_drvdata ndd = container_of(kref, typeof(ndd), kref);
	266	struct device *dev = ndd->dev;
	267	struct resource res, _r;
	268
	269	dev_dbg(dev, "%s\n", __func__);
	270
	271	nvdimm_bus_lock(dev);
	272	for_each_dpa_resource_safe(ndd, res, _r)
	273	nvdimm_free_dpa(ndd, res);
	274	nvdimm_bus_unlock(dev);
	275
a06a7576	276	kvfree(ndd->data);
bf9bccc1 DW	277	kfree(ndd);
	278	put_device(dev);
	279	}
	280
	281	void get_ndd(struct nvdimm_drvdata *ndd)
	282	{
	283	kref_get(&ndd->kref);
	284	}
	285
	286	void put_ndd(struct nvdimm_drvdata *ndd)
	287	{
	288	if (ndd)
	289	kref_put(&ndd->kref, nvdimm_drvdata_release);
	290	}
	291
e6dfb2de DW	292	const char nvdimm_name(struct nvdimm nvdimm)
	293	{
	294	return dev_name(&nvdimm->dev);
	295	}
	296	EXPORT_SYMBOL_GPL(nvdimm_name);
	297
ba9c8dd3 DW	298	struct kobject nvdimm_kobj(struct nvdimm nvdimm)
	299	{
	300	return &nvdimm->dev.kobj;
	301	}
	302	EXPORT_SYMBOL_GPL(nvdimm_kobj);
	303
e3654eca DW	304	unsigned long nvdimm_cmd_mask(struct nvdimm *nvdimm)
	305	{
	306	return nvdimm->cmd_mask;
	307	}
	308	EXPORT_SYMBOL_GPL(nvdimm_cmd_mask);
	309
e6dfb2de DW	310	void nvdimm_provider_data(struct nvdimm nvdimm)
e6dfb2de DW	311	{
62232e45 DW	312	if (nvdimm)
	313	return nvdimm->provider_data;
	314	return NULL;
e6dfb2de DW	315	}
	316	EXPORT_SYMBOL_GPL(nvdimm_provider_data);
	317
62232e45 DW	318	static ssize_t commands_show(struct device *dev,
	319	struct device_attribute attr, char buf)
	320	{
	321	struct nvdimm *nvdimm = to_nvdimm(dev);
	322	int cmd, len = 0;
	323
e3654eca	324	if (!nvdimm->cmd_mask)
62232e45 DW	325	return sprintf(buf, "\n");
62232e45 DW	326
e3654eca	327	for_each_set_bit(cmd, &nvdimm->cmd_mask, BITS_PER_LONG)
62232e45 DW	328	len += sprintf(buf + len, "%s ", nvdimm_cmd_name(cmd));
	329	len += sprintf(buf + len, "\n");
	330	return len;
	331	}
	332	static DEVICE_ATTR_RO(commands);
	333
efbf6f50 DW	334	static ssize_t flags_show(struct device *dev,
	335	struct device_attribute attr, char buf)
	336	{
	337	struct nvdimm *nvdimm = to_nvdimm(dev);
	338
	339	return sprintf(buf, "%s%s\n",
	340	test_bit(NDD_ALIASING, &nvdimm->flags) ? "alias " : "",
	341	test_bit(NDD_LOCKED, &nvdimm->flags) ? "lock " : "");
	342	}
	343	static DEVICE_ATTR_RO(flags);
	344
eaf96153 DW	345	static ssize_t state_show(struct device dev, struct device_attribute attr,
	346	char *buf)
	347	{
	348	struct nvdimm *nvdimm = to_nvdimm(dev);
	349
	350	/*
	351	* The state may be in the process of changing, userspace should
	352	* quiesce probing if it wants a static answer
	353	*/
	354	nvdimm_bus_lock(dev);
	355	nvdimm_bus_unlock(dev);
	356	return sprintf(buf, "%s\n", atomic_read(&nvdimm->busy)
	357	? "active" : "idle");
	358	}
	359	static DEVICE_ATTR_RO(state);
	360
0ba1c634 DW	361	static ssize_t available_slots_show(struct device *dev,
	362	struct device_attribute attr, char buf)
	363	{
	364	struct nvdimm_drvdata *ndd = dev_get_drvdata(dev);
	365	ssize_t rc;
	366	u32 nfree;
	367
	368	if (!ndd)
	369	return -ENXIO;
	370
	371	nvdimm_bus_lock(dev);
	372	nfree = nd_label_nfree(ndd);
	373	if (nfree - 1 > nfree) {
	374	dev_WARN_ONCE(dev, 1, "we ate our last label?\n");
	375	nfree = 0;
	376	} else
	377	nfree--;
	378	rc = sprintf(buf, "%d\n", nfree);
	379	nvdimm_bus_unlock(dev);
	380	return rc;
	381	}
	382	static DEVICE_ATTR_RO(available_slots);
	383
62232e45	384	static struct attribute *nvdimm_attributes[] = {
eaf96153	385	&dev_attr_state.attr,
efbf6f50	386	&dev_attr_flags.attr,
62232e45	387	&dev_attr_commands.attr,
0ba1c634	388	&dev_attr_available_slots.attr,
62232e45 DW	389	NULL,
	390	};
	391
	392	struct attribute_group nvdimm_attribute_group = {
	393	.attrs = nvdimm_attributes,
	394	};
	395	EXPORT_SYMBOL_GPL(nvdimm_attribute_group);
	396
e6dfb2de	397	struct nvdimm nvdimm_create(struct nvdimm_bus nvdimm_bus, void *provider_data,
62232e45	398	const struct attribute_group **groups, unsigned long flags,
e5ae3b25 DW	399	unsigned long cmd_mask, int num_flush,
e5ae3b25 DW	400	struct resource *flush_wpq)
e6dfb2de DW	401	{
	402	struct nvdimm nvdimm = kzalloc(sizeof(nvdimm), GFP_KERNEL);
	403	struct device *dev;
	404
	405	if (!nvdimm)
	406	return NULL;
	407
	408	nvdimm->id = ida_simple_get(&dimm_ida, 0, 0, GFP_KERNEL);
	409	if (nvdimm->id < 0) {
	410	kfree(nvdimm);
	411	return NULL;
	412	}
	413	nvdimm->provider_data = provider_data;
	414	nvdimm->flags = flags;
e3654eca	415	nvdimm->cmd_mask = cmd_mask;
e5ae3b25 DW	416	nvdimm->num_flush = num_flush;
e5ae3b25 DW	417	nvdimm->flush_wpq = flush_wpq;
eaf96153	418	atomic_set(&nvdimm->busy, 0);
e6dfb2de DW	419	dev = &nvdimm->dev;
	420	dev_set_name(dev, "nmem%d", nvdimm->id);
	421	dev->parent = &nvdimm_bus->dev;
	422	dev->type = &nvdimm_device_type;
62232e45	423	dev->devt = MKDEV(nvdimm_major, nvdimm->id);
e6dfb2de	424	dev->groups = groups;
4d88a97a	425	nd_device_register(dev);
e6dfb2de DW	426
	427	return nvdimm;
	428	}
	429	EXPORT_SYMBOL_GPL(nvdimm_create);
4d88a97a	430
762d067d	431	int alias_dpa_busy(struct device dev, void data)
a1f3e4d6	432	{
fe514739	433	resource_size_t map_end, blk_start, new;
a1f3e4d6 DW	434	struct blk_alloc_info *info = data;
	435	struct nd_mapping *nd_mapping;
	436	struct nd_region *nd_region;
	437	struct nvdimm_drvdata *ndd;
	438	struct resource *res;
	439	int i;
	440
c9e582aa	441	if (!is_memory(dev))
a1f3e4d6 DW	442	return 0;
	443
	444	nd_region = to_nd_region(dev);
	445	for (i = 0; i < nd_region->ndr_mappings; i++) {
	446	nd_mapping = &nd_region->mapping[i];
	447	if (nd_mapping->nvdimm == info->nd_mapping->nvdimm)
	448	break;
	449	}
	450
	451	if (i >= nd_region->ndr_mappings)
	452	return 0;
	453
	454	ndd = to_ndd(nd_mapping);
	455	map_end = nd_mapping->start + nd_mapping->size - 1;
	456	blk_start = nd_mapping->start;
762d067d DW	457
	458	/*
	459	* In the allocation case ->res is set to free space that we are
	460	* looking to validate against PMEM aliasing collision rules
	461	* (i.e. BLK is allocated after all aliased PMEM).
	462	*/
	463	if (info->res) {
	464	if (info->res->start >= nd_mapping->start
	465	&& info->res->start < map_end)
	466	/* pass */;
	467	else
	468	return 0;
	469	}
	470
a1f3e4d6 DW	471	retry:
	472	/*
	473	* Find the free dpa from the end of the last pmem allocation to
fe514739	474	* the end of the interleave-set mapping.
a1f3e4d6	475	*/
a1f3e4d6	476	for_each_dpa_resource(ndd, res) {
fe514739 DW	477	if (strncmp(res->name, "pmem", 4) != 0)
fe514739 DW	478	continue;
a1f3e4d6 DW	479	if ((res->start >= blk_start && res->start < map_end)
	480	\|\| (res->end >= blk_start
	481	&& res->end <= map_end)) {
fe514739 DW	482	new = max(blk_start, min(map_end + 1, res->end + 1));
	483	if (new != blk_start) {
	484	blk_start = new;
	485	goto retry;
	486	}
a1f3e4d6 DW	487	}
	488	}
	489
762d067d DW	490	/* update the free space range with the probed blk_start */
	491	if (info->res && blk_start > info->res->start) {
	492	info->res->start = max(info->res->start, blk_start);
	493	if (info->res->start > info->res->end)
	494	info->res->end = info->res->start - 1;
	495	return 1;
	496	}
	497
fe514739	498	info->available -= blk_start - nd_mapping->start;
762d067d	499
a1f3e4d6 DW	500	return 0;
	501	}
	502
1b40e09a DW	503	/**
	504	* nd_blk_available_dpa - account the unused dpa of BLK region
	505	* @nd_mapping: container of dpa-resource-root + labels
	506	*
a1f3e4d6 DW	507	* Unlike PMEM, BLK namespaces can occupy discontiguous DPA ranges, but
	508	* we arrange for them to never start at an lower dpa than the last
	509	* PMEM allocation in an aliased region.
1b40e09a	510	*/
a1f3e4d6	511	resource_size_t nd_blk_available_dpa(struct nd_region *nd_region)
1b40e09a	512	{
a1f3e4d6 DW	513	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&nd_region->dev);
a1f3e4d6 DW	514	struct nd_mapping *nd_mapping = &nd_region->mapping[0];
1b40e09a	515	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
a1f3e4d6 DW	516	struct blk_alloc_info info = {
	517	.nd_mapping = nd_mapping,
	518	.available = nd_mapping->size,
762d067d	519	.res = NULL,
a1f3e4d6	520	};
1b40e09a DW	521	struct resource *res;
	522
	523	if (!ndd)
	524	return 0;
	525
a1f3e4d6	526	device_for_each_child(&nvdimm_bus->dev, &info, alias_dpa_busy);
1b40e09a	527
a1f3e4d6 DW	528	/* now account for busy blk allocations in unaliased dpa */
	529	for_each_dpa_resource(ndd, res) {
	530	if (strncmp(res->name, "blk", 3) != 0)
	531	continue;
fe514739	532	info.available -= resource_size(res);
a1f3e4d6 DW	533	}
	534
	535	return info.available;
1b40e09a DW	536	}
1b40e09a DW	537
bf9bccc1 DW	538	/**
	539	* nd_pmem_available_dpa - for the given dimm+region account unallocated dpa
	540	* @nd_mapping: container of dpa-resource-root + labels
	541	* @nd_region: constrain available space check to this reference region
	542	* @overlap: calculate available space assuming this level of overlap
	543	*
	544	* Validate that a PMEM label, if present, aligns with the start of an
	545	* interleave set and truncate the available size at the lowest BLK
	546	* overlap point.
	547	*
	548	* The expectation is that this routine is called multiple times as it
	549	* probes for the largest BLK encroachment for any single member DIMM of
	550	* the interleave set. Once that value is determined the PMEM-limit for
	551	* the set can be established.
	552	*/
	553	resource_size_t nd_pmem_available_dpa(struct nd_region *nd_region,
	554	struct nd_mapping nd_mapping, resource_size_t overlap)
	555	{
	556	resource_size_t map_start, map_end, busy = 0, available, blk_start;
	557	struct nvdimm_drvdata *ndd = to_ndd(nd_mapping);
	558	struct resource *res;
	559	const char *reason;
	560
	561	if (!ndd)
	562	return 0;
	563
	564	map_start = nd_mapping->start;
	565	map_end = map_start + nd_mapping->size - 1;
	566	blk_start = max(map_start, map_end + 1 - *overlap);
a1f3e4d6	567	for_each_dpa_resource(ndd, res) {
bf9bccc1 DW	568	if (res->start >= map_start && res->start < map_end) {
bf9bccc1 DW	569	if (strncmp(res->name, "blk", 3) == 0)
a1f3e4d6 DW	570	blk_start = min(blk_start,
	571	max(map_start, res->start));
	572	else if (res->end > map_end) {
bf9bccc1 DW	573	reason = "misaligned to iset";
bf9bccc1 DW	574	goto err;
a1f3e4d6	575	} else
bf9bccc1	576	busy += resource_size(res);
bf9bccc1 DW	577	} else if (res->end >= map_start && res->end <= map_end) {
	578	if (strncmp(res->name, "blk", 3) == 0) {
	579	/*
	580	* If a BLK allocation overlaps the start of
	581	* PMEM the entire interleave set may now only
	582	* be used for BLK.
	583	*/
	584	blk_start = map_start;
a1f3e4d6 DW	585	} else
a1f3e4d6 DW	586	busy += resource_size(res);
bf9bccc1 DW	587	} else if (map_start > res->start && map_start < res->end) {
	588	/* total eclipse of the mapping */
	589	busy += nd_mapping->size;
	590	blk_start = map_start;
	591	}
a1f3e4d6	592	}
bf9bccc1 DW	593
	594	*overlap = map_end + 1 - blk_start;
	595	available = blk_start - map_start;
	596	if (busy < available)
	597	return available - busy;
	598	return 0;
	599
	600	err:
bf9bccc1 DW	601	nd_dbg_dpa(nd_region, ndd, res, "%s\n", reason);
	602	return 0;
	603	}
	604
4a826c83 DW	605	void nvdimm_free_dpa(struct nvdimm_drvdata ndd, struct resource res)
	606	{
	607	WARN_ON_ONCE(!is_nvdimm_bus_locked(ndd->dev));
	608	kfree(res->name);
	609	__release_region(&ndd->dpa, res->start, resource_size(res));
	610	}
	611
	612	struct resource nvdimm_allocate_dpa(struct nvdimm_drvdata ndd,
	613	struct nd_label_id *label_id, resource_size_t start,
	614	resource_size_t n)
	615	{
	616	char name = kmemdup(label_id, sizeof(label_id), GFP_KERNEL);
	617	struct resource *res;
	618
	619	if (!name)
	620	return NULL;
	621
	622	WARN_ON_ONCE(!is_nvdimm_bus_locked(ndd->dev));
	623	res = __request_region(&ndd->dpa, start, n, name, 0);
	624	if (!res)
	625	kfree(name);
	626	return res;
	627	}
	628
bf9bccc1 DW	629	/**
	630	* nvdimm_allocated_dpa - sum up the dpa currently allocated to this label_id
	631	* @nvdimm: container of dpa-resource-root + labels
	632	* @label_id: dpa resource name of the form {pmem\|blk}-<human readable uuid>
	633	*/
	634	resource_size_t nvdimm_allocated_dpa(struct nvdimm_drvdata *ndd,
	635	struct nd_label_id *label_id)
	636	{
	637	resource_size_t allocated = 0;
	638	struct resource *res;
	639
	640	for_each_dpa_resource(ndd, res)
	641	if (strcmp(res->name, label_id->id) == 0)
	642	allocated += resource_size(res);
	643
	644	return allocated;
	645	}
	646
4d88a97a DW	647	static int count_dimms(struct device dev, void c)
	648	{
	649	int *count = c;
	650
	651	if (is_nvdimm(dev))
	652	(*count)++;
	653	return 0;
	654	}
	655
	656	int nvdimm_bus_check_dimm_count(struct nvdimm_bus *nvdimm_bus, int dimm_count)
	657	{
	658	int count = 0;
	659	/* Flush any possible dimm registration failures */
	660	nd_synchronize();
	661
	662	device_for_each_child(&nvdimm_bus->dev, &count, count_dimms);
	663	dev_dbg(&nvdimm_bus->dev, "%s: count: %d\n", __func__, count);
	664	if (count != dimm_count)
	665	return -ENXIO;
	666	return 0;
	667	}
	668	EXPORT_SYMBOL_GPL(nvdimm_bus_check_dimm_count);
b354aba0 DW	669
	670	void __exit nvdimm_devs_exit(void)
	671	{
	672	ida_destroy(&dimm_ida);
	673	}