[linux-block.git] / drivers / nvdimm / btt_devs.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
 */
#include <linux/blkdev.h>
#include <linux/device.h>
#include <linux/sizes.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include "nd-core.h"
#include "btt.h"
#include "nd.h"

static void nd_btt_release(struct device *dev)
{
	struct nd_region *nd_region = to_nd_region(dev->parent);
	struct nd_btt *nd_btt = to_nd_btt(dev);

	dev_dbg(dev, "trace\n");
	nd_detach_ndns(&nd_btt->dev, &nd_btt->ndns);
	ida_free(&nd_region->btt_ida, nd_btt->id);
	kfree(nd_btt->uuid);
	kfree(nd_btt);
}

struct nd_btt *to_nd_btt(struct device *dev)
{
	struct nd_btt *nd_btt = container_of(dev, struct nd_btt, dev);

	WARN_ON(!is_nd_btt(dev));
	return nd_btt;
}
EXPORT_SYMBOL(to_nd_btt);

static const unsigned long btt_lbasize_supported[] = { 512, 520, 528,
	4096, 4104, 4160, 4224, 0 };

static ssize_t sector_size_show(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	struct nd_btt *nd_btt = to_nd_btt(dev);

	return nd_size_select_show(nd_btt->lbasize, btt_lbasize_supported, buf);
}

static ssize_t sector_size_store(struct device *dev,
		struct device_attribute *attr, const char *buf, size_t len)
{
	struct nd_btt *nd_btt = to_nd_btt(dev);
	ssize_t rc;

	device_lock(dev);
	nvdimm_bus_lock(dev);
	rc = nd_size_select_store(dev, buf, &nd_btt->lbasize,
			btt_lbasize_supported);
	dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
			buf[len - 1] == '\n' ? "" : "\n");
	nvdimm_bus_unlock(dev);
	device_unlock(dev);

	return rc ? rc : len;
}
static DEVICE_ATTR_RW(sector_size);

static ssize_t uuid_show(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	struct nd_btt *nd_btt = to_nd_btt(dev);

	if (nd_btt->uuid)
		return sprintf(buf, "%pUb\n", nd_btt->uuid);
	return sprintf(buf, "\n");
}

static ssize_t uuid_store(struct device *dev,
		struct device_attribute *attr, const char *buf, size_t len)
{
	struct nd_btt *nd_btt = to_nd_btt(dev);
	ssize_t rc;

	device_lock(dev);
	rc = nd_uuid_store(dev, &nd_btt->uuid, buf, len);
	dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
			buf[len - 1] == '\n' ? "" : "\n");
	device_unlock(dev);

	return rc ? rc : len;
}
static DEVICE_ATTR_RW(uuid);

static ssize_t namespace_show(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	struct nd_btt *nd_btt = to_nd_btt(dev);
	ssize_t rc;

	nvdimm_bus_lock(dev);
	rc = sprintf(buf, "%s\n", nd_btt->ndns
			? dev_name(&nd_btt->ndns->dev) : "");
	nvdimm_bus_unlock(dev);
	return rc;
}

static ssize_t namespace_store(struct device *dev,
		struct device_attribute *attr, const char *buf, size_t len)
{
	struct nd_btt *nd_btt = to_nd_btt(dev);
	ssize_t rc;

	device_lock(dev);
	nvdimm_bus_lock(dev);
	rc = nd_namespace_store(dev, &nd_btt->ndns, buf, len);
	dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
			buf[len - 1] == '\n' ? "" : "\n");
	nvdimm_bus_unlock(dev);
	device_unlock(dev);

	return rc;
}
static DEVICE_ATTR_RW(namespace);

static ssize_t size_show(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	struct nd_btt *nd_btt = to_nd_btt(dev);
	ssize_t rc;

	device_lock(dev);
	if (dev->driver)
		rc = sprintf(buf, "%llu\n", nd_btt->size);
	else {
		/* no size to convey if the btt instance is disabled */
		rc = -ENXIO;
	}
	device_unlock(dev);

	return rc;
}
static DEVICE_ATTR_RO(size);

static ssize_t log_zero_flags_show(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	return sprintf(buf, "Y\n");
}
static DEVICE_ATTR_RO(log_zero_flags);

static struct attribute *nd_btt_attributes[] = {
	&dev_attr_sector_size.attr,
	&dev_attr_namespace.attr,
	&dev_attr_uuid.attr,
	&dev_attr_size.attr,
	&dev_attr_log_zero_flags.attr,
	NULL,
};

static struct attribute_group nd_btt_attribute_group = {
	.attrs = nd_btt_attributes,
};

static const struct attribute_group *nd_btt_attribute_groups[] = {
	&nd_btt_attribute_group,
	&nd_device_attribute_group,
	&nd_numa_attribute_group,
	NULL,
};

static const struct device_type nd_btt_device_type = {
	.name = "nd_btt",
	.release = nd_btt_release,
	.groups = nd_btt_attribute_groups,
};

bool is_nd_btt(struct device *dev)
{
	return dev->type == &nd_btt_device_type;
}
EXPORT_SYMBOL(is_nd_btt);

static struct lock_class_key nvdimm_btt_key;

static struct device *__nd_btt_create(struct nd_region *nd_region,
				      unsigned long lbasize, uuid_t *uuid,
				      struct nd_namespace_common *ndns)
{
	struct nd_btt *nd_btt;
	struct device *dev;

	nd_btt = kzalloc(sizeof(*nd_btt), GFP_KERNEL);
	if (!nd_btt)
		return NULL;

	nd_btt->id = ida_alloc(&nd_region->btt_ida, GFP_KERNEL);
	if (nd_btt->id < 0)
		goto out_nd_btt;

	nd_btt->lbasize = lbasize;
	if (uuid) {
		uuid = kmemdup(uuid, 16, GFP_KERNEL);
		if (!uuid)
			goto out_put_id;
	}
	nd_btt->uuid = uuid;
	dev = &nd_btt->dev;
	dev_set_name(dev, "btt%d.%d", nd_region->id, nd_btt->id);
	dev->parent = &nd_region->dev;
	dev->type = &nd_btt_device_type;
	device_initialize(&nd_btt->dev);
	lockdep_set_class(&nd_btt->dev.mutex, &nvdimm_btt_key);
	if (ndns && !__nd_attach_ndns(&nd_btt->dev, ndns, &nd_btt->ndns)) {
		dev_dbg(&ndns->dev, "failed, already claimed by %s\n",
				dev_name(ndns->claim));
		put_device(dev);
		return NULL;
	}
	return dev;

out_put_id:
	ida_free(&nd_region->btt_ida, nd_btt->id);

out_nd_btt:
	kfree(nd_btt);
	return NULL;
}

struct device *nd_btt_create(struct nd_region *nd_region)
{
	struct device *dev = __nd_btt_create(nd_region, 0, NULL, NULL);

	nd_device_register(dev);
	return dev;
}

/**
 * nd_btt_arena_is_valid - check if the metadata layout is valid
 * @nd_btt:	device with BTT geometry and backing device info
 * @super:	pointer to the arena's info block being tested
 *
 * Check consistency of the btt info block with itself by validating
 * the checksum, and with the parent namespace by verifying the
 * parent_uuid contained in the info block with the one supplied in.
 *
 * Returns:
 * false for an invalid info block, true for a valid one
 */
bool nd_btt_arena_is_valid(struct nd_btt *nd_btt, struct btt_sb *super)
{
	const uuid_t *ns_uuid = nd_dev_to_uuid(&nd_btt->ndns->dev);
	uuid_t parent_uuid;
	u64 checksum;

	if (memcmp(super->signature, BTT_SIG, BTT_SIG_LEN) != 0)
		return false;

	import_uuid(&parent_uuid, super->parent_uuid);
	if (!uuid_is_null(&parent_uuid))
		if (!uuid_equal(&parent_uuid, ns_uuid))
			return false;

	checksum = le64_to_cpu(super->checksum);
	super->checksum = 0;
	if (checksum != nd_sb_checksum((struct nd_gen_sb *) super))
		return false;
	super->checksum = cpu_to_le64(checksum);

	/* TODO: figure out action for this */
	if ((le32_to_cpu(super->flags) & IB_FLAG_ERROR_MASK) != 0)
		dev_info(&nd_btt->dev, "Found arena with an error flag\n");

	return true;
}
EXPORT_SYMBOL(nd_btt_arena_is_valid);

int nd_btt_version(struct nd_btt *nd_btt, struct nd_namespace_common *ndns,
		struct btt_sb *btt_sb)
{
	if (ndns->claim_class == NVDIMM_CCLASS_BTT2) {
		/* Probe/setup for BTT v2.0 */
		nd_btt->initial_offset = 0;
		nd_btt->version_major = 2;
		nd_btt->version_minor = 0;
		if (nvdimm_read_bytes(ndns, 0, btt_sb, sizeof(*btt_sb), 0))
			return -ENXIO;
		if (!nd_btt_arena_is_valid(nd_btt, btt_sb))
			return -ENODEV;
		if ((le16_to_cpu(btt_sb->version_major) != 2) ||
				(le16_to_cpu(btt_sb->version_minor) != 0))
			return -ENODEV;
	} else {
		/*
		 * Probe/setup for BTT v1.1 (NVDIMM_CCLASS_NONE or
		 * NVDIMM_CCLASS_BTT)
		 */
		nd_btt->initial_offset = SZ_4K;
		nd_btt->version_major = 1;
		nd_btt->version_minor = 1;
		if (nvdimm_read_bytes(ndns, SZ_4K, btt_sb, sizeof(*btt_sb), 0))
			return -ENXIO;
		if (!nd_btt_arena_is_valid(nd_btt, btt_sb))
			return -ENODEV;
		if ((le16_to_cpu(btt_sb->version_major) != 1) ||
				(le16_to_cpu(btt_sb->version_minor) != 1))
			return -ENODEV;
	}
	return 0;
}
EXPORT_SYMBOL(nd_btt_version);

static int __nd_btt_probe(struct nd_btt *nd_btt,
		struct nd_namespace_common *ndns, struct btt_sb *btt_sb)
{
	int rc;

	if (!btt_sb || !ndns || !nd_btt)
		return -ENODEV;

	if (nvdimm_namespace_capacity(ndns) < SZ_16M)
		return -ENXIO;

	rc = nd_btt_version(nd_btt, ndns, btt_sb);
	if (rc < 0)
		return rc;

	nd_btt->lbasize = le32_to_cpu(btt_sb->external_lbasize);
	nd_btt->uuid = kmemdup(&btt_sb->uuid, sizeof(uuid_t), GFP_KERNEL);
	if (!nd_btt->uuid)
		return -ENOMEM;

	nd_device_register(&nd_btt->dev);

	return 0;
}

int nd_btt_probe(struct device *dev, struct nd_namespace_common *ndns)
{
	int rc;
	struct device *btt_dev;
	struct btt_sb *btt_sb;
	struct nd_region *nd_region = to_nd_region(ndns->dev.parent);

	if (ndns->force_raw)
		return -ENODEV;

	switch (ndns->claim_class) {
	case NVDIMM_CCLASS_NONE:
	case NVDIMM_CCLASS_BTT:
	case NVDIMM_CCLASS_BTT2:
		break;
	default:
		return -ENODEV;
	}

	nvdimm_bus_lock(&ndns->dev);
	btt_dev = __nd_btt_create(nd_region, 0, NULL, ndns);
	nvdimm_bus_unlock(&ndns->dev);
	if (!btt_dev)
		return -ENOMEM;
	btt_sb = devm_kzalloc(dev, sizeof(*btt_sb), GFP_KERNEL);
	rc = __nd_btt_probe(to_nd_btt(btt_dev), ndns, btt_sb);
	dev_dbg(dev, "btt: %s\n", rc == 0 ? dev_name(btt_dev) : "<none>");
	if (rc < 0) {
		struct nd_btt *nd_btt = to_nd_btt(btt_dev);

		nd_detach_ndns(btt_dev, &nd_btt->ndns);
		put_device(btt_dev);
	}

	return rc;
}
EXPORT_SYMBOL(nd_btt_probe);
Commit	Line	Data
5b497af4	1	// SPDX-License-Identifier: GPL-2.0-only
8c2f7e86 DW	2	/*
8c2f7e86 DW	3	* Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
8c2f7e86 DW	4	*/
	5	#include <linux/blkdev.h>
	6	#include <linux/device.h>
8c2f7e86 DW	7	#include <linux/sizes.h>
	8	#include <linux/slab.h>
	9	#include <linux/fs.h>
	10	#include <linux/mm.h>
	11	#include "nd-core.h"
	12	#include "btt.h"
	13	#include "nd.h"
	14
8c2f7e86 DW	15	static void nd_btt_release(struct device *dev)
	16	{
	17	struct nd_region *nd_region = to_nd_region(dev->parent);
	18	struct nd_btt *nd_btt = to_nd_btt(dev);
	19
426824d6	20	dev_dbg(dev, "trace\n");
e1455744	21	nd_detach_ndns(&nd_btt->dev, &nd_btt->ndns);
deb369e0	22	ida_free(&nd_region->btt_ida, nd_btt->id);
8c2f7e86 DW	23	kfree(nd_btt->uuid);
	24	kfree(nd_btt);
	25	}
	26
8c2f7e86 DW	27	struct nd_btt to_nd_btt(struct device dev)
	28	{
	29	struct nd_btt *nd_btt = container_of(dev, struct nd_btt, dev);
	30
	31	WARN_ON(!is_nd_btt(dev));
	32	return nd_btt;
	33	}
	34	EXPORT_SYMBOL(to_nd_btt);
	35
41cd8b70 VV	36	static const unsigned long btt_lbasize_supported[] = { 512, 520, 528,
41cd8b70 VV	37	4096, 4104, 4160, 4224, 0 };
8c2f7e86 DW	38
	39	static ssize_t sector_size_show(struct device *dev,
	40	struct device_attribute attr, char buf)
	41	{
	42	struct nd_btt *nd_btt = to_nd_btt(dev);
	43
b2c48f9f	44	return nd_size_select_show(nd_btt->lbasize, btt_lbasize_supported, buf);
8c2f7e86 DW	45	}
	46
	47	static ssize_t sector_size_store(struct device *dev,
	48	struct device_attribute attr, const char buf, size_t len)
	49	{
	50	struct nd_btt *nd_btt = to_nd_btt(dev);
	51	ssize_t rc;
	52
81beea55	53	device_lock(dev);
8c2f7e86	54	nvdimm_bus_lock(dev);
b2c48f9f	55	rc = nd_size_select_store(dev, buf, &nd_btt->lbasize,
8c2f7e86	56	btt_lbasize_supported);
426824d6 DW	57	dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
426824d6 DW	58	buf[len - 1] == '\n' ? "" : "\n");
8c2f7e86	59	nvdimm_bus_unlock(dev);
81beea55	60	device_unlock(dev);
8c2f7e86 DW	61
	62	return rc ? rc : len;
	63	}
	64	static DEVICE_ATTR_RW(sector_size);
	65
	66	static ssize_t uuid_show(struct device *dev,
	67	struct device_attribute attr, char buf)
	68	{
	69	struct nd_btt *nd_btt = to_nd_btt(dev);
	70
	71	if (nd_btt->uuid)
	72	return sprintf(buf, "%pUb\n", nd_btt->uuid);
	73	return sprintf(buf, "\n");
	74	}
	75
	76	static ssize_t uuid_store(struct device *dev,
	77	struct device_attribute attr, const char buf, size_t len)
	78	{
	79	struct nd_btt *nd_btt = to_nd_btt(dev);
	80	ssize_t rc;
	81
81beea55	82	device_lock(dev);
8c2f7e86	83	rc = nd_uuid_store(dev, &nd_btt->uuid, buf, len);
426824d6 DW	84	dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
426824d6 DW	85	buf[len - 1] == '\n' ? "" : "\n");
81beea55	86	device_unlock(dev);
8c2f7e86 DW	87
	88	return rc ? rc : len;
	89	}
	90	static DEVICE_ATTR_RW(uuid);
	91
	92	static ssize_t namespace_show(struct device *dev,
	93	struct device_attribute attr, char buf)
	94	{
	95	struct nd_btt *nd_btt = to_nd_btt(dev);
	96	ssize_t rc;
	97
	98	nvdimm_bus_lock(dev);
	99	rc = sprintf(buf, "%s\n", nd_btt->ndns
	100	? dev_name(&nd_btt->ndns->dev) : "");
	101	nvdimm_bus_unlock(dev);
	102	return rc;
	103	}
	104
8c2f7e86 DW	105	static ssize_t namespace_store(struct device *dev,
	106	struct device_attribute attr, const char buf, size_t len)
	107	{
e1455744	108	struct nd_btt *nd_btt = to_nd_btt(dev);
8c2f7e86 DW	109	ssize_t rc;
8c2f7e86 DW	110
81beea55	111	device_lock(dev);
4be9c1fc	112	nvdimm_bus_lock(dev);
e1455744	113	rc = nd_namespace_store(dev, &nd_btt->ndns, buf, len);
426824d6 DW	114	dev_dbg(dev, "result: %zd wrote: %s%s", rc, buf,
426824d6 DW	115	buf[len - 1] == '\n' ? "" : "\n");
8c2f7e86	116	nvdimm_bus_unlock(dev);
81beea55	117	device_unlock(dev);
8c2f7e86 DW	118
	119	return rc;
	120	}
	121	static DEVICE_ATTR_RW(namespace);
	122
abe8b4e3 VV	123	static ssize_t size_show(struct device *dev,
	124	struct device_attribute attr, char buf)
	125	{
	126	struct nd_btt *nd_btt = to_nd_btt(dev);
	127	ssize_t rc;
	128
81beea55	129	device_lock(dev);
abe8b4e3 VV	130	if (dev->driver)
	131	rc = sprintf(buf, "%llu\n", nd_btt->size);
	132	else {
	133	/* no size to convey if the btt instance is disabled */
	134	rc = -ENXIO;
	135	}
81beea55	136	device_unlock(dev);
abe8b4e3 VV	137
	138	return rc;
	139	}
	140	static DEVICE_ATTR_RO(size);
	141
9dedc73a VV	142	static ssize_t log_zero_flags_show(struct device *dev,
	143	struct device_attribute attr, char buf)
	144	{
	145	return sprintf(buf, "Y\n");
	146	}
	147	static DEVICE_ATTR_RO(log_zero_flags);
	148
8c2f7e86 DW	149	static struct attribute *nd_btt_attributes[] = {
	150	&dev_attr_sector_size.attr,
	151	&dev_attr_namespace.attr,
	152	&dev_attr_uuid.attr,
abe8b4e3	153	&dev_attr_size.attr,
9dedc73a	154	&dev_attr_log_zero_flags.attr,
8c2f7e86 DW	155	NULL,
	156	};
	157
	158	static struct attribute_group nd_btt_attribute_group = {
	159	.attrs = nd_btt_attributes,
	160	};
	161
	162	static const struct attribute_group *nd_btt_attribute_groups[] = {
	163	&nd_btt_attribute_group,
	164	&nd_device_attribute_group,
74ae66c3	165	&nd_numa_attribute_group,
8c2f7e86 DW	166	NULL,
	167	};
	168
78c81cc8 DW	169	static const struct device_type nd_btt_device_type = {
	170	.name = "nd_btt",
	171	.release = nd_btt_release,
	172	.groups = nd_btt_attribute_groups,
	173	};
	174
	175	bool is_nd_btt(struct device *dev)
	176	{
	177	return dev->type == &nd_btt_device_type;
	178	}
	179	EXPORT_SYMBOL(is_nd_btt);
	180
4a0079bc DW	181	static struct lock_class_key nvdimm_btt_key;
4a0079bc DW	182
8c2f7e86	183	static struct device __nd_btt_create(struct nd_region nd_region,
d1c6e08e DW	184	unsigned long lbasize, uuid_t *uuid,
d1c6e08e DW	185	struct nd_namespace_common *ndns)
8c2f7e86 DW	186	{
	187	struct nd_btt *nd_btt;
	188	struct device *dev;
	189
	190	nd_btt = kzalloc(sizeof(*nd_btt), GFP_KERNEL);
	191	if (!nd_btt)
	192	return NULL;
	193
deb369e0	194	nd_btt->id = ida_alloc(&nd_region->btt_ida, GFP_KERNEL);
486fa92d AP	195	if (nd_btt->id < 0)
486fa92d AP	196	goto out_nd_btt;
8c2f7e86 DW	197
8c2f7e86 DW	198	nd_btt->lbasize = lbasize;
486fa92d	199	if (uuid) {
8c2f7e86	200	uuid = kmemdup(uuid, 16, GFP_KERNEL);
486fa92d AP	201	if (!uuid)
	202	goto out_put_id;
	203	}
8c2f7e86 DW	204	nd_btt->uuid = uuid;
	205	dev = &nd_btt->dev;
	206	dev_set_name(dev, "btt%d.%d", nd_region->id, nd_btt->id);
	207	dev->parent = &nd_region->dev;
	208	dev->type = &nd_btt_device_type;
8c2f7e86	209	device_initialize(&nd_btt->dev);
4a0079bc	210	lockdep_set_class(&nd_btt->dev.mutex, &nvdimm_btt_key);
e1455744	211	if (ndns && !__nd_attach_ndns(&nd_btt->dev, ndns, &nd_btt->ndns)) {
426824d6 DW	212	dev_dbg(&ndns->dev, "failed, already claimed by %s\n",
426824d6 DW	213	dev_name(ndns->claim));
8c2f7e86 DW	214	put_device(dev);
	215	return NULL;
	216	}
	217	return dev;
486fa92d AP	218
486fa92d AP	219	out_put_id:
deb369e0	220	ida_free(&nd_region->btt_ida, nd_btt->id);
486fa92d AP	221
	222	out_nd_btt:
	223	kfree(nd_btt);
	224	return NULL;
8c2f7e86 DW	225	}
	226
	227	struct device nd_btt_create(struct nd_region nd_region)
	228	{
	229	struct device *dev = __nd_btt_create(nd_region, 0, NULL, NULL);
	230
4a0079bc	231	nd_device_register(dev);
8c2f7e86 DW	232	return dev;
	233	}
	234
ab45e763 VV	235	/**
	236	* nd_btt_arena_is_valid - check if the metadata layout is valid
	237	* @nd_btt: device with BTT geometry and backing device info
	238	* @super: pointer to the arena's info block being tested
	239	*
	240	* Check consistency of the btt info block with itself by validating
6ec68954 VV	241	* the checksum, and with the parent namespace by verifying the
6ec68954 VV	242	* parent_uuid contained in the info block with the one supplied in.
ab45e763 VV	243	*
	244	* Returns:
	245	* false for an invalid info block, true for a valid one
	246	*/
	247	bool nd_btt_arena_is_valid(struct nd_btt nd_btt, struct btt_sb super)
	248	{
d1c6e08e DW	249	const uuid_t *ns_uuid = nd_dev_to_uuid(&nd_btt->ndns->dev);
d1c6e08e DW	250	uuid_t parent_uuid;
ab45e763 VV	251	u64 checksum;
	252
	253	if (memcmp(super->signature, BTT_SIG, BTT_SIG_LEN) != 0)
	254	return false;
	255
d1c6e08e DW	256	import_uuid(&parent_uuid, super->parent_uuid);
	257	if (!uuid_is_null(&parent_uuid))
	258	if (!uuid_equal(&parent_uuid, ns_uuid))
6ec68954 VV	259	return false;
6ec68954 VV	260
ab45e763 VV	261	checksum = le64_to_cpu(super->checksum);
ab45e763 VV	262	super->checksum = 0;
e1455744	263	if (checksum != nd_sb_checksum((struct nd_gen_sb *) super))
ab45e763 VV	264	return false;
	265	super->checksum = cpu_to_le64(checksum);
	266
	267	/* TODO: figure out action for this */
	268	if ((le32_to_cpu(super->flags) & IB_FLAG_ERROR_MASK) != 0)
	269	dev_info(&nd_btt->dev, "Found arena with an error flag\n");
	270
	271	return true;
	272	}
	273	EXPORT_SYMBOL(nd_btt_arena_is_valid);
	274
14e49454 VV	275	int nd_btt_version(struct nd_btt nd_btt, struct nd_namespace_common ndns,
	276	struct btt_sb *btt_sb)
	277	{
	278	if (ndns->claim_class == NVDIMM_CCLASS_BTT2) {
	279	/* Probe/setup for BTT v2.0 */
	280	nd_btt->initial_offset = 0;
	281	nd_btt->version_major = 2;
	282	nd_btt->version_minor = 0;
	283	if (nvdimm_read_bytes(ndns, 0, btt_sb, sizeof(*btt_sb), 0))
	284	return -ENXIO;
	285	if (!nd_btt_arena_is_valid(nd_btt, btt_sb))
	286	return -ENODEV;
	287	if ((le16_to_cpu(btt_sb->version_major) != 2) \|\|
	288	(le16_to_cpu(btt_sb->version_minor) != 0))
	289	return -ENODEV;
	290	} else {
	291	/*
	292	* Probe/setup for BTT v1.1 (NVDIMM_CCLASS_NONE or
	293	* NVDIMM_CCLASS_BTT)
	294	*/
	295	nd_btt->initial_offset = SZ_4K;
	296	nd_btt->version_major = 1;
	297	nd_btt->version_minor = 1;
	298	if (nvdimm_read_bytes(ndns, SZ_4K, btt_sb, sizeof(*btt_sb), 0))
	299	return -ENXIO;
	300	if (!nd_btt_arena_is_valid(nd_btt, btt_sb))
	301	return -ENODEV;
	302	if ((le16_to_cpu(btt_sb->version_major) != 1) \|\|
	303	(le16_to_cpu(btt_sb->version_minor) != 1))
	304	return -ENODEV;
	305	}
	306	return 0;
	307	}
	308	EXPORT_SYMBOL(nd_btt_version);
	309
8c2f7e86 DW	310	static int __nd_btt_probe(struct nd_btt *nd_btt,
	311	struct nd_namespace_common ndns, struct btt_sb btt_sb)
	312	{
14e49454 VV	313	int rc;
14e49454 VV	314
8c2f7e86 DW	315	if (!btt_sb \|\| !ndns \|\| !nd_btt)
	316	return -ENODEV;
	317
8c2f7e86 DW	318	if (nvdimm_namespace_capacity(ndns) < SZ_16M)
	319	return -ENXIO;
	320
14e49454 VV	321	rc = nd_btt_version(nd_btt, ndns, btt_sb);
	322	if (rc < 0)
	323	return rc;
8c2f7e86 DW	324
8c2f7e86 DW	325	nd_btt->lbasize = le32_to_cpu(btt_sb->external_lbasize);
d1c6e08e	326	nd_btt->uuid = kmemdup(&btt_sb->uuid, sizeof(uuid_t), GFP_KERNEL);
8c2f7e86 DW	327	if (!nd_btt->uuid)
	328	return -ENOMEM;
	329
4a0079bc	330	nd_device_register(&nd_btt->dev);
8c2f7e86 DW	331
	332	return 0;
	333	}
	334
200c79da	335	int nd_btt_probe(struct device dev, struct nd_namespace_common ndns)
8c2f7e86 DW	336	{
8c2f7e86 DW	337	int rc;
e32bc729	338	struct device *btt_dev;
8c2f7e86 DW	339	struct btt_sb *btt_sb;
	340	struct nd_region *nd_region = to_nd_region(ndns->dev.parent);
	341
	342	if (ndns->force_raw)
	343	return -ENODEV;
	344
b3fde74e DW	345	switch (ndns->claim_class) {
	346	case NVDIMM_CCLASS_NONE:
	347	case NVDIMM_CCLASS_BTT:
14e49454	348	case NVDIMM_CCLASS_BTT2:
b3fde74e DW	349	break;
	350	default:
	351	return -ENODEV;
	352	}
	353
8c2f7e86	354	nvdimm_bus_lock(&ndns->dev);
e32bc729	355	btt_dev = __nd_btt_create(nd_region, 0, NULL, ndns);
8c2f7e86	356	nvdimm_bus_unlock(&ndns->dev);
e32bc729	357	if (!btt_dev)
8c2f7e86	358	return -ENOMEM;
e32bc729 DW	359	btt_sb = devm_kzalloc(dev, sizeof(*btt_sb), GFP_KERNEL);
e32bc729 DW	360	rc = __nd_btt_probe(to_nd_btt(btt_dev), ndns, btt_sb);
426824d6	361	dev_dbg(dev, "btt: %s\n", rc == 0 ? dev_name(btt_dev) : "<none>");
8c2f7e86	362	if (rc < 0) {
e32bc729	363	struct nd_btt *nd_btt = to_nd_btt(btt_dev);
e1455744	364
452bae0a	365	nd_detach_ndns(btt_dev, &nd_btt->ndns);
e32bc729	366	put_device(btt_dev);
8c2f7e86 DW	367	}
	368
	369	return rc;
	370	}
	371	EXPORT_SYMBOL(nd_btt_probe);