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

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

void __nd_detach_ndns(struct device *dev, struct nd_namespace_common **_ndns)
{
	struct nd_namespace_common *ndns = *_ndns;
	struct nvdimm_bus *nvdimm_bus;

	if (!ndns)
		return;

	nvdimm_bus = walk_to_nvdimm_bus(&ndns->dev);
	lockdep_assert_held(&nvdimm_bus->reconfig_mutex);
	dev_WARN_ONCE(dev, ndns->claim != dev, "%s: invalid claim\n", __func__);
	ndns->claim = NULL;
	*_ndns = NULL;
	put_device(&ndns->dev);
}

void nd_detach_ndns(struct device *dev,
		struct nd_namespace_common **_ndns)
{
	struct nd_namespace_common *ndns = *_ndns;

	if (!ndns)
		return;
	get_device(&ndns->dev);
	nvdimm_bus_lock(&ndns->dev);
	__nd_detach_ndns(dev, _ndns);
	nvdimm_bus_unlock(&ndns->dev);
	put_device(&ndns->dev);
}

bool __nd_attach_ndns(struct device *dev, struct nd_namespace_common *attach,
		struct nd_namespace_common **_ndns)
{
	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&attach->dev);

	if (attach->claim)
		return false;
	lockdep_assert_held(&nvdimm_bus->reconfig_mutex);
	dev_WARN_ONCE(dev, *_ndns, "%s: invalid claim\n", __func__);
	attach->claim = dev;
	*_ndns = attach;
	get_device(&attach->dev);
	return true;
}

bool nd_attach_ndns(struct device *dev, struct nd_namespace_common *attach,
		struct nd_namespace_common **_ndns)
{
	bool claimed;

	nvdimm_bus_lock(&attach->dev);
	claimed = __nd_attach_ndns(dev, attach, _ndns);
	nvdimm_bus_unlock(&attach->dev);
	return claimed;
}

static int namespace_match(struct device *dev, void *data)
{
	char *name = data;

	return strcmp(name, dev_name(dev)) == 0;
}

static bool is_idle(struct device *dev, struct nd_namespace_common *ndns)
{
	struct nd_region *nd_region = to_nd_region(dev->parent);
	struct device *seed = NULL;

	if (is_nd_btt(dev))
		seed = nd_region->btt_seed;
	else if (is_nd_pfn(dev))
		seed = nd_region->pfn_seed;
	else if (is_nd_dax(dev))
		seed = nd_region->dax_seed;

	if (seed == dev || ndns || dev->driver)
		return false;
	return true;
}

struct nd_pfn *to_nd_pfn_safe(struct device *dev)
{
	/*
	 * pfn device attributes are re-used by dax device instances, so we
	 * need to be careful to correct device-to-nd_pfn conversion.
	 */
	if (is_nd_pfn(dev))
		return to_nd_pfn(dev);

	if (is_nd_dax(dev)) {
		struct nd_dax *nd_dax = to_nd_dax(dev);

		return &nd_dax->nd_pfn;
	}

	WARN_ON(1);
	return NULL;
}

static void nd_detach_and_reset(struct device *dev,
		struct nd_namespace_common **_ndns)
{
	/* detach the namespace and destroy / reset the device */
	__nd_detach_ndns(dev, _ndns);
	if (is_idle(dev, *_ndns)) {
		nd_device_unregister(dev, ND_ASYNC);
	} else if (is_nd_btt(dev)) {
		struct nd_btt *nd_btt = to_nd_btt(dev);

		nd_btt->lbasize = 0;
		kfree(nd_btt->uuid);
		nd_btt->uuid = NULL;
	} else if (is_nd_pfn(dev) || is_nd_dax(dev)) {
		struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);

		kfree(nd_pfn->uuid);
		nd_pfn->uuid = NULL;
		nd_pfn->mode = PFN_MODE_NONE;
	}
}

ssize_t nd_namespace_store(struct device *dev,
		struct nd_namespace_common **_ndns, const char *buf,
		size_t len)
{
	struct nd_namespace_common *ndns;
	struct device *found;
	char *name;

	if (dev->driver) {
		dev_dbg(dev, "namespace already active\n");
		return -EBUSY;
	}

	name = kstrndup(buf, len, GFP_KERNEL);
	if (!name)
		return -ENOMEM;
	strim(name);

	if (strncmp(name, "namespace", 9) == 0 || strcmp(name, "") == 0)
		/* pass */;
	else {
		len = -EINVAL;
		goto out;
	}

	ndns = *_ndns;
	if (strcmp(name, "") == 0) {
		nd_detach_and_reset(dev, _ndns);
		goto out;
	} else if (ndns) {
		dev_dbg(dev, "namespace already set to: %s\n",
				dev_name(&ndns->dev));
		len = -EBUSY;
		goto out;
	}

	found = device_find_child(dev->parent, name, namespace_match);
	if (!found) {
		dev_dbg(dev, "'%s' not found under %s\n", name,
				dev_name(dev->parent));
		len = -ENODEV;
		goto out;
	}

	ndns = to_ndns(found);

	switch (ndns->claim_class) {
	case NVDIMM_CCLASS_NONE:
		break;
	case NVDIMM_CCLASS_BTT:
	case NVDIMM_CCLASS_BTT2:
		if (!is_nd_btt(dev)) {
			len = -EBUSY;
			goto out_attach;
		}
		break;
	case NVDIMM_CCLASS_PFN:
		if (!is_nd_pfn(dev)) {
			len = -EBUSY;
			goto out_attach;
		}
		break;
	case NVDIMM_CCLASS_DAX:
		if (!is_nd_dax(dev)) {
			len = -EBUSY;
			goto out_attach;
		}
		break;
	default:
		len = -EBUSY;
		goto out_attach;
		break;
	}

	if (__nvdimm_namespace_capacity(ndns) < SZ_16M) {
		dev_dbg(dev, "%s too small to host\n", name);
		len = -ENXIO;
		goto out_attach;
	}

	WARN_ON_ONCE(!is_nvdimm_bus_locked(dev));
	if (!__nd_attach_ndns(dev, ndns, _ndns)) {
		dev_dbg(dev, "%s already claimed\n",
				dev_name(&ndns->dev));
		len = -EBUSY;
	}

 out_attach:
	put_device(&ndns->dev); /* from device_find_child */
 out:
	kfree(name);
	return len;
}

/*
 * nd_sb_checksum: compute checksum for a generic info block
 *
 * Returns a fletcher64 checksum of everything in the given info block
 * except the last field (since that's where the checksum lives).
 */
u64 nd_sb_checksum(struct nd_gen_sb *nd_gen_sb)
{
	u64 sum;
	__le64 sum_save;

	BUILD_BUG_ON(sizeof(struct btt_sb) != SZ_4K);
	BUILD_BUG_ON(sizeof(struct nd_pfn_sb) != SZ_4K);
	BUILD_BUG_ON(sizeof(struct nd_gen_sb) != SZ_4K);

	sum_save = nd_gen_sb->checksum;
	nd_gen_sb->checksum = 0;
	sum = nd_fletcher64(nd_gen_sb, sizeof(*nd_gen_sb), 1);
	nd_gen_sb->checksum = sum_save;
	return sum;
}
EXPORT_SYMBOL(nd_sb_checksum);

static int nsio_rw_bytes(struct nd_namespace_common *ndns,
		resource_size_t offset, void *buf, size_t size, int rw,
		unsigned long flags)
{
	struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
	unsigned int sz_align = ALIGN(size + (offset & (512 - 1)), 512);
	sector_t sector = offset >> 9;
	int rc = 0, ret = 0;

	if (unlikely(!size))
		return 0;

	if (unlikely(offset + size > nsio->size)) {
		dev_WARN_ONCE(&ndns->dev, 1, "request out of range\n");
		return -EFAULT;
	}

	if (rw == READ) {
		if (unlikely(is_bad_pmem(&nsio->bb, sector, sz_align)))
			return -EIO;
		if (copy_mc_to_kernel(buf, nsio->addr + offset, size) != 0)
			return -EIO;
		return 0;
	}

	if (unlikely(is_bad_pmem(&nsio->bb, sector, sz_align))) {
		if (IS_ALIGNED(offset, 512) && IS_ALIGNED(size, 512)
				&& !(flags & NVDIMM_IO_ATOMIC)) {
			long cleared;

			might_sleep();
			cleared = nvdimm_clear_poison(&ndns->dev,
					nsio->res.start + offset, size);
			if (cleared < size)
				rc = -EIO;
			if (cleared > 0 && cleared / 512) {
				cleared /= 512;
				badblocks_clear(&nsio->bb, sector, cleared);
			}
			arch_invalidate_pmem(nsio->addr + offset, size);
		} else
			rc = -EIO;
	}

	memcpy_flushcache(nsio->addr + offset, buf, size);
	ret = nvdimm_flush(to_nd_region(ndns->dev.parent), NULL);
	if (ret)
		rc = ret;

	return rc;
}

int devm_nsio_enable(struct device *dev, struct nd_namespace_io *nsio,
		resource_size_t size)
{
	struct nd_namespace_common *ndns = &nsio->common;
	struct range range = {
		.start = nsio->res.start,
		.end = nsio->res.end,
	};

	nsio->size = size;
	if (!devm_request_mem_region(dev, range.start, size,
				dev_name(&ndns->dev))) {
		dev_warn(dev, "could not reserve region %pR\n", &nsio->res);
		return -EBUSY;
	}

	ndns->rw_bytes = nsio_rw_bytes;
	if (devm_init_badblocks(dev, &nsio->bb))
		return -ENOMEM;
	nvdimm_badblocks_populate(to_nd_region(ndns->dev.parent), &nsio->bb,
			&range);

	nsio->addr = devm_memremap(dev, range.start, size, ARCH_MEMREMAP_PMEM);

	return PTR_ERR_OR_ZERO(nsio->addr);
}

void devm_nsio_disable(struct device *dev, struct nd_namespace_io *nsio)
{
	struct resource *res = &nsio->res;

	devm_memunmap(dev, nsio->addr);
	devm_exit_badblocks(dev, &nsio->bb);
	devm_release_mem_region(dev, res->start, nsio->size);
}
Commit	Line	Data
5b497af4	1	// SPDX-License-Identifier: GPL-2.0-only
e1455744 DW	2	/*
e1455744 DW	3	* Copyright(c) 2013-2015 Intel Corporation. All rights reserved.
e1455744 DW	4	*/
	5	#include <linux/device.h>
	6	#include <linux/sizes.h>
5ae96d77	7	#include <linux/badblocks.h>
e1455744	8	#include "nd-core.h"
f2b61257	9	#include "pmem.h"
e1455744 DW	10	#include "pfn.h"
	11	#include "btt.h"
	12	#include "nd.h"
	13
	14	void __nd_detach_ndns(struct device dev, struct nd_namespace_common *_ndns)
	15	{
	16	struct nd_namespace_common ndns = _ndns;
452bae0a	17	struct nvdimm_bus *nvdimm_bus;
e1455744	18
452bae0a DW	19	if (!ndns)
	20	return;
	21
	22	nvdimm_bus = walk_to_nvdimm_bus(&ndns->dev);
	23	lockdep_assert_held(&nvdimm_bus->reconfig_mutex);
9cf8bd52	24	dev_WARN_ONCE(dev, ndns->claim != dev, "%s: invalid claim\n", __func__);
e1455744 DW	25	ndns->claim = NULL;
	26	*_ndns = NULL;
	27	put_device(&ndns->dev);
	28	}
	29
	30	void nd_detach_ndns(struct device *dev,
	31	struct nd_namespace_common **_ndns)
	32	{
	33	struct nd_namespace_common ndns = _ndns;
	34
	35	if (!ndns)
	36	return;
	37	get_device(&ndns->dev);
452bae0a	38	nvdimm_bus_lock(&ndns->dev);
e1455744	39	__nd_detach_ndns(dev, _ndns);
452bae0a	40	nvdimm_bus_unlock(&ndns->dev);
e1455744 DW	41	put_device(&ndns->dev);
	42	}
	43
	44	bool __nd_attach_ndns(struct device dev, struct nd_namespace_common attach,
	45	struct nd_namespace_common **_ndns)
	46	{
452bae0a DW	47	struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(&attach->dev);
452bae0a DW	48
e1455744 DW	49	if (attach->claim)
e1455744 DW	50	return false;
452bae0a	51	lockdep_assert_held(&nvdimm_bus->reconfig_mutex);
9cf8bd52	52	dev_WARN_ONCE(dev, *_ndns, "%s: invalid claim\n", __func__);
e1455744 DW	53	attach->claim = dev;
	54	*_ndns = attach;
	55	get_device(&attach->dev);
	56	return true;
	57	}
	58
	59	bool nd_attach_ndns(struct device dev, struct nd_namespace_common attach,
	60	struct nd_namespace_common **_ndns)
	61	{
	62	bool claimed;
	63
452bae0a	64	nvdimm_bus_lock(&attach->dev);
e1455744	65	claimed = __nd_attach_ndns(dev, attach, _ndns);
452bae0a	66	nvdimm_bus_unlock(&attach->dev);
e1455744 DW	67	return claimed;
	68	}
	69
	70	static int namespace_match(struct device dev, void data)
	71	{
	72	char *name = data;
	73
	74	return strcmp(name, dev_name(dev)) == 0;
	75	}
	76
	77	static bool is_idle(struct device dev, struct nd_namespace_common ndns)
	78	{
	79	struct nd_region *nd_region = to_nd_region(dev->parent);
	80	struct device *seed = NULL;
	81
	82	if (is_nd_btt(dev))
	83	seed = nd_region->btt_seed;
	84	else if (is_nd_pfn(dev))
	85	seed = nd_region->pfn_seed;
cd03412a DW	86	else if (is_nd_dax(dev))
cd03412a DW	87	seed = nd_region->dax_seed;
e1455744 DW	88
	89	if (seed == dev \|\| ndns \|\| dev->driver)
	90	return false;
	91	return true;
	92	}
	93
03dca343 DW	94	struct nd_pfn to_nd_pfn_safe(struct device dev)
	95	{
	96	/*
	97	* pfn device attributes are re-used by dax device instances, so we
	98	* need to be careful to correct device-to-nd_pfn conversion.
	99	*/
	100	if (is_nd_pfn(dev))
	101	return to_nd_pfn(dev);
	102
	103	if (is_nd_dax(dev)) {
	104	struct nd_dax *nd_dax = to_nd_dax(dev);
	105
	106	return &nd_dax->nd_pfn;
	107	}
	108
	109	WARN_ON(1);
	110	return NULL;
	111	}
	112
e1455744 DW	113	static void nd_detach_and_reset(struct device *dev,
	114	struct nd_namespace_common **_ndns)
	115	{
	116	/* detach the namespace and destroy / reset the device */
452bae0a	117	__nd_detach_ndns(dev, _ndns);
e1455744 DW	118	if (is_idle(dev, *_ndns)) {
	119	nd_device_unregister(dev, ND_ASYNC);
	120	} else if (is_nd_btt(dev)) {
	121	struct nd_btt *nd_btt = to_nd_btt(dev);
	122
	123	nd_btt->lbasize = 0;
	124	kfree(nd_btt->uuid);
	125	nd_btt->uuid = NULL;
03dca343 DW	126	} else if (is_nd_pfn(dev) \|\| is_nd_dax(dev)) {
03dca343 DW	127	struct nd_pfn *nd_pfn = to_nd_pfn_safe(dev);
e1455744 DW	128
	129	kfree(nd_pfn->uuid);
	130	nd_pfn->uuid = NULL;
	131	nd_pfn->mode = PFN_MODE_NONE;
	132	}
	133	}
	134
	135	ssize_t nd_namespace_store(struct device *dev,
	136	struct nd_namespace_common *_ndns, const char buf,
	137	size_t len)
	138	{
	139	struct nd_namespace_common *ndns;
	140	struct device *found;
	141	char *name;
	142
	143	if (dev->driver) {
426824d6	144	dev_dbg(dev, "namespace already active\n");
e1455744 DW	145	return -EBUSY;
	146	}
	147
	148	name = kstrndup(buf, len, GFP_KERNEL);
	149	if (!name)
	150	return -ENOMEM;
	151	strim(name);
	152
	153	if (strncmp(name, "namespace", 9) == 0 \|\| strcmp(name, "") == 0)
	154	/* pass */;
	155	else {
	156	len = -EINVAL;
	157	goto out;
	158	}
	159
	160	ndns = *_ndns;
	161	if (strcmp(name, "") == 0) {
	162	nd_detach_and_reset(dev, _ndns);
	163	goto out;
	164	} else if (ndns) {
	165	dev_dbg(dev, "namespace already set to: %s\n",
	166	dev_name(&ndns->dev));
	167	len = -EBUSY;
	168	goto out;
	169	}
	170
	171	found = device_find_child(dev->parent, name, namespace_match);
	172	if (!found) {
	173	dev_dbg(dev, "'%s' not found under %s\n", name,
	174	dev_name(dev->parent));
	175	len = -ENODEV;
	176	goto out;
	177	}
	178
	179	ndns = to_ndns(found);
b3fde74e DW	180
	181	switch (ndns->claim_class) {
	182	case NVDIMM_CCLASS_NONE:
	183	break;
	184	case NVDIMM_CCLASS_BTT:
14e49454	185	case NVDIMM_CCLASS_BTT2:
b3fde74e DW	186	if (!is_nd_btt(dev)) {
	187	len = -EBUSY;
	188	goto out_attach;
	189	}
	190	break;
	191	case NVDIMM_CCLASS_PFN:
	192	if (!is_nd_pfn(dev)) {
	193	len = -EBUSY;
	194	goto out_attach;
	195	}
	196	break;
	197	case NVDIMM_CCLASS_DAX:
	198	if (!is_nd_dax(dev)) {
	199	len = -EBUSY;
	200	goto out_attach;
	201	}
	202	break;
	203	default:
	204	len = -EBUSY;
	205	goto out_attach;
	206	break;
	207	}
	208
e1455744 DW	209	if (__nvdimm_namespace_capacity(ndns) < SZ_16M) {
	210	dev_dbg(dev, "%s too small to host\n", name);
	211	len = -ENXIO;
	212	goto out_attach;
	213	}
	214
	215	WARN_ON_ONCE(!is_nvdimm_bus_locked(dev));
452bae0a	216	if (!__nd_attach_ndns(dev, ndns, _ndns)) {
e1455744 DW	217	dev_dbg(dev, "%s already claimed\n",
	218	dev_name(&ndns->dev));
	219	len = -EBUSY;
	220	}
	221
	222	out_attach:
	223	put_device(&ndns->dev); /* from device_find_child */
	224	out:
	225	kfree(name);
	226	return len;
	227	}
	228
	229	/*
	230	* nd_sb_checksum: compute checksum for a generic info block
	231	*
	232	* Returns a fletcher64 checksum of everything in the given info block
	233	* except the last field (since that's where the checksum lives).
	234	*/
	235	u64 nd_sb_checksum(struct nd_gen_sb *nd_gen_sb)
	236	{
	237	u64 sum;
	238	__le64 sum_save;
	239
	240	BUILD_BUG_ON(sizeof(struct btt_sb) != SZ_4K);
	241	BUILD_BUG_ON(sizeof(struct nd_pfn_sb) != SZ_4K);
	242	BUILD_BUG_ON(sizeof(struct nd_gen_sb) != SZ_4K);
	243
	244	sum_save = nd_gen_sb->checksum;
	245	nd_gen_sb->checksum = 0;
	246	sum = nd_fletcher64(nd_gen_sb, sizeof(*nd_gen_sb), 1);
	247	nd_gen_sb->checksum = sum_save;
	248	return sum;
	249	}
	250	EXPORT_SYMBOL(nd_sb_checksum);
200c79da DW	251
200c79da DW	252	static int nsio_rw_bytes(struct nd_namespace_common *ndns,
3ae3d67b VV	253	resource_size_t offset, void *buf, size_t size, int rw,
3ae3d67b VV	254	unsigned long flags)
200c79da DW	255	{
200c79da DW	256	struct nd_namespace_io *nsio = to_nd_namespace_io(&ndns->dev);
82bf1037 DJ	257	unsigned int sz_align = ALIGN(size + (offset & (512 - 1)), 512);
82bf1037 DJ	258	sector_t sector = offset >> 9;
c5d4355d	259	int rc = 0, ret = 0;
82bf1037 DJ	260
	261	if (unlikely(!size))
	262	return 0;
200c79da DW	263
	264	if (unlikely(offset + size > nsio->size)) {
	265	dev_WARN_ONCE(&ndns->dev, 1, "request out of range\n");
	266	return -EFAULT;
	267	}
	268
	269	if (rw == READ) {
82bf1037	270	if (unlikely(is_bad_pmem(&nsio->bb, sector, sz_align)))
200c79da	271	return -EIO;
ec6347bb	272	if (copy_mc_to_kernel(buf, nsio->addr + offset, size) != 0)
60622d68	273	return -EIO;
b62cc6fd	274	return 0;
d37806dc FF	275	}
	276
	277	if (unlikely(is_bad_pmem(&nsio->bb, sector, sz_align))) {
a3e9af95	278	if (IS_ALIGNED(offset, 512) && IS_ALIGNED(size, 512)
7e5a21df	279	&& !(flags & NVDIMM_IO_ATOMIC)) {
d37806dc FF	280	long cleared;
d37806dc FF	281
1db1f3ce	282	might_sleep();
97681f9b TK	283	cleared = nvdimm_clear_poison(&ndns->dev,
97681f9b TK	284	nsio->res.start + offset, size);
868f036f	285	if (cleared < size)
82bf1037	286	rc = -EIO;
868f036f DW	287	if (cleared > 0 && cleared / 512) {
	288	cleared /= 512;
	289	badblocks_clear(&nsio->bb, sector, cleared);
d37806dc	290	}
f2b61257	291	arch_invalidate_pmem(nsio->addr + offset, size);
d37806dc FF	292	} else
d37806dc FF	293	rc = -EIO;
200c79da DW	294	}
200c79da DW	295
0aed55af	296	memcpy_flushcache(nsio->addr + offset, buf, size);
c5d4355d PG	297	ret = nvdimm_flush(to_nd_region(ndns->dev.parent), NULL);
	298	if (ret)
	299	rc = ret;
d37806dc	300
82bf1037	301	return rc;
200c79da DW	302	}
200c79da DW	303
8f4b01fc AK	304	int devm_nsio_enable(struct device dev, struct nd_namespace_io nsio,
8f4b01fc AK	305	resource_size_t size)
200c79da	306	{
200c79da	307	struct nd_namespace_common *ndns = &nsio->common;
a4574f63 DW	308	struct range range = {
	309	.start = nsio->res.start,
	310	.end = nsio->res.end,
	311	};
200c79da	312
8f4b01fc	313	nsio->size = size;
a4574f63	314	if (!devm_request_mem_region(dev, range.start, size,
450c6633	315	dev_name(&ndns->dev))) {
a4574f63	316	dev_warn(dev, "could not reserve region %pR\n", &nsio->res);
200c79da DW	317	return -EBUSY;
	318	}
	319
	320	ndns->rw_bytes = nsio_rw_bytes;
	321	if (devm_init_badblocks(dev, &nsio->bb))
	322	return -ENOMEM;
	323	nvdimm_badblocks_populate(to_nd_region(ndns->dev.parent), &nsio->bb,
a4574f63	324	&range);
200c79da	325
a4574f63	326	nsio->addr = devm_memremap(dev, range.start, size, ARCH_MEMREMAP_PMEM);
42588958 DW	327
42588958 DW	328	return PTR_ERR_OR_ZERO(nsio->addr);
200c79da	329	}
200c79da DW	330
	331	void devm_nsio_disable(struct device dev, struct nd_namespace_io nsio)
	332	{
	333	struct resource *res = &nsio->res;
	334
	335	devm_memunmap(dev, nsio->addr);
	336	devm_exit_badblocks(dev, &nsio->bb);
8f4b01fc	337	devm_release_mem_region(dev, res->start, nsio->size);
200c79da	338	}