@@ -2240,7 +2240,7 @@ static int ars_status_process_records(struct acpi_nfit_desc *acpi_desc,
if (ars_status->out_length
< 44 + sizeof(struct nd_ars_record) * (i + 1))
break;
- rc = nvdimm_bus_add_poison(nvdimm_bus,
+ rc = nvdimm_bus_add_badrange(nvdimm_bus,
ars_status->records[i].err_address,
ars_status->records[i].length);
if (rc)
@@ -67,7 +67,7 @@ static int nfit_handle_mce(struct notifier_block *nb, unsigned long val,
continue;
/* If this fails due to an -ENOMEM, there is little we can do */
- nvdimm_bus_add_poison(acpi_desc->nvdimm_bus,
+ nvdimm_bus_add_badrange(acpi_desc->nvdimm_bus,
ALIGN(mce->addr, L1_CACHE_BYTES),
L1_CACHE_BYTES);
nvdimm_region_notify(nfit_spa->nd_region,
@@ -20,6 +20,7 @@ libnvdimm-y += region_devs.o
libnvdimm-y += region.o
libnvdimm-y += namespace_devs.o
libnvdimm-y += label.o
+libnvdimm-y += badrange.o
libnvdimm-$(CONFIG_ND_CLAIM) += claim.o
libnvdimm-$(CONFIG_BTT) += btt_devs.o
libnvdimm-$(CONFIG_NVDIMM_PFN) += pfn_devs.o
new file mode 100644
@@ -0,0 +1,294 @@
+/*
+ * Copyright(c) 2017 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/libnvdimm.h>
+#include <linux/badblocks.h>
+#include <linux/export.h>
+#include <linux/module.h>
+#include <linux/blkdev.h>
+#include <linux/device.h>
+#include <linux/ctype.h>
+#include <linux/ndctl.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/io.h>
+#include "nd-core.h"
+#include "nd.h"
+
+void badrange_init(struct badrange *badrange)
+{
+ INIT_LIST_HEAD(&badrange->list);
+ spin_lock_init(&badrange->lock);
+}
+EXPORT_SYMBOL_GPL(badrange_init);
+
+static void append_badrange_entry(struct badrange *badrange,
+ struct badrange_entry *be, u64 addr, u64 length)
+{
+ lockdep_assert_held(&badrange->lock);
+ be->start = addr;
+ be->length = length;
+ list_add_tail(&be->list, &badrange->list);
+}
+
+static int alloc_and_append_badrange_entry(struct badrange *badrange,
+ u64 addr, u64 length, gfp_t flags)
+{
+ struct badrange_entry *be;
+
+ be = kzalloc(sizeof(*be), flags);
+ if (!be)
+ return -ENOMEM;
+
+ append_badrange_entry(badrange, be, addr, length);
+ return 0;
+}
+
+static int add_badrange(struct badrange *badrange, u64 addr, u64 length)
+{
+ struct badrange_entry *be, *be_new;
+
+ spin_unlock(&badrange->lock);
+ be_new = kzalloc(sizeof(*be_new), GFP_KERNEL);
+ spin_lock(&badrange->lock);
+
+ if (list_empty(&badrange->list)) {
+ if (!be_new)
+ return -ENOMEM;
+ append_badrange_entry(badrange, be_new, addr, length);
+ return 0;
+ }
+
+ /*
+ * There is a chance this is a duplicate, check for those first.
+ * This will be the common case as ARS_STATUS returns all known
+ * errors in the SPA space, and we can't query it per region
+ */
+ list_for_each_entry(be, &badrange->list, list)
+ if (be->start == addr) {
+ /* If length has changed, update this list entry */
+ if (be->length != length)
+ be->length = length;
+ kfree(be_new);
+ return 0;
+ }
+
+ /*
+ * If not a duplicate or a simple length update, add the entry as is,
+ * as any overlapping ranges will get resolved when the list is consumed
+ * and converted to badblocks
+ */
+ if (!be_new)
+ return -ENOMEM;
+ append_badrange_entry(badrange, be_new, addr, length);
+
+ return 0;
+}
+
+int badrange_add(struct badrange *badrange, u64 addr, u64 length)
+{
+ int rc;
+
+ spin_lock(&badrange->lock);
+ rc = add_badrange(badrange, addr, length);
+ spin_unlock(&badrange->lock);
+
+ return rc;
+}
+EXPORT_SYMBOL_GPL(badrange_add);
+
+void badrange_forget(struct badrange *badrange, phys_addr_t start,
+ unsigned int len)
+{
+ struct list_head *badrange_list = &badrange->list;
+ u64 clr_end = start + len - 1;
+ struct badrange_entry *be, *next;
+
+ spin_lock(&badrange->lock);
+ WARN_ON_ONCE(list_empty(badrange_list));
+
+ /*
+ * [start, clr_end] is the badrange interval being cleared.
+ * [be->start, be_end] is the badrange_list entry we're comparing
+ * the above interval against. The badrange list entry may need
+ * to be modified (update either start or length), deleted, or
+ * split into two based on the overlap characteristics
+ */
+
+ list_for_each_entry_safe(be, next, badrange_list, list) {
+ u64 be_end = be->start + be->length - 1;
+
+ /* Skip intervals with no intersection */
+ if (be_end < start)
+ continue;
+ if (be->start > clr_end)
+ continue;
+ /* Delete combeetely overlapped badrange entries */
+ if ((be->start >= start) && (be_end <= clr_end)) {
+ list_del(&be->list);
+ kfree(be);
+ continue;
+ }
+ /* Adjust start point of partially cleared entries */
+ if ((start <= be->start) && (clr_end > be->start)) {
+ be->length -= clr_end - be->start + 1;
+ be->start = clr_end + 1;
+ continue;
+ }
+ /* Adjust be->length for partial clearing at the tail end */
+ if ((be->start < start) && (be_end <= clr_end)) {
+ /* be->start remains the same */
+ be->length = start - be->start;
+ continue;
+ }
+ /*
+ * If clearing in the middle of an entry, we split it into
+ * two by modifying the current entry to represent one half of
+ * the split, and adding a new entry for the second half.
+ */
+ if ((be->start < start) && (be_end > clr_end)) {
+ u64 new_start = clr_end + 1;
+ u64 new_len = be_end - new_start + 1;
+
+ /* Add new entry covering the right half */
+ alloc_and_append_badrange_entry(badrange, new_start,
+ new_len, GFP_NOWAIT);
+ /* Adjust this entry to cover the left half */
+ be->length = start - be->start;
+ continue;
+ }
+ }
+ spin_unlock(&badrange->lock);
+}
+EXPORT_SYMBOL_GPL(badrange_forget);
+
+static void set_badblock(struct badblocks *bb, sector_t s, int num)
+{
+ dev_dbg(bb->dev, "Found a bad range (0x%llx, 0x%llx)\n",
+ (u64) s * 512, (u64) num * 512);
+ /* this isn't an error as the hardware will still throw an exception */
+ if (badblocks_set(bb, s, num, 1))
+ dev_info_once(bb->dev, "%s: failed for sector %llx\n",
+ __func__, (u64) s);
+}
+
+/**
+ * __add_badblock_range() - Convert a physical address range to bad sectors
+ * @bb: badblocks instance to populate
+ * @ns_offset: namespace offset where the error range begins (in bytes)
+ * @len: number of bytes of badrange to be added
+ *
+ * This assumes that the range provided with (ns_offset, len) is within
+ * the bounds of physical addresses for this namespace, i.e. lies in the
+ * interval [ns_start, ns_start + ns_size)
+ */
+static void __add_badblock_range(struct badblocks *bb, u64 ns_offset, u64 len)
+{
+ const unsigned int sector_size = 512;
+ sector_t start_sector, end_sector;
+ u64 num_sectors;
+ u32 rem;
+
+ start_sector = div_u64(ns_offset, sector_size);
+ end_sector = div_u64_rem(ns_offset + len, sector_size, &rem);
+ if (rem)
+ end_sector++;
+ num_sectors = end_sector - start_sector;
+
+ if (unlikely(num_sectors > (u64)INT_MAX)) {
+ u64 remaining = num_sectors;
+ sector_t s = start_sector;
+
+ while (remaining) {
+ int done = min_t(u64, remaining, INT_MAX);
+
+ set_badblock(bb, s, done);
+ remaining -= done;
+ s += done;
+ }
+ } else
+ set_badblock(bb, start_sector, num_sectors);
+}
+
+static void badblocks_populate(struct badrange *badrange,
+ struct badblocks *bb, const struct resource *res)
+{
+ struct badrange_entry *be;
+
+ if (list_empty(&badrange->list))
+ return;
+
+ list_for_each_entry(be, &badrange->list, list) {
+ u64 be_end = be->start + be->length - 1;
+
+ /* Discard intervals with no intersection */
+ if (be_end < res->start)
+ continue;
+ if (be->start > res->end)
+ continue;
+ /* Deal with any overlap after start of the namespace */
+ if (be->start >= res->start) {
+ u64 start = be->start;
+ u64 len;
+
+ if (be_end <= res->end)
+ len = be->length;
+ else
+ len = res->start + resource_size(res)
+ - be->start;
+ __add_badblock_range(bb, start - res->start, len);
+ continue;
+ }
+ /*
+ * Deal with overlap for badrange starting before
+ * the namespace.
+ */
+ if (be->start < res->start) {
+ u64 len;
+
+ if (be_end < res->end)
+ len = be->start + be->length - res->start;
+ else
+ len = resource_size(res);
+ __add_badblock_range(bb, 0, len);
+ }
+ }
+}
+
+/**
+ * nvdimm_badblocks_populate() - Convert a list of badranges to badblocks
+ * @region: parent region of the range to interrogate
+ * @bb: badblocks instance to populate
+ * @res: resource range to consider
+ *
+ * The badrange list generated during bus initialization may contain
+ * multiple, possibly overlapping physical address ranges. Compare each
+ * of these ranges to the resource range currently being initialized,
+ * and add badblocks entries for all matching sub-ranges
+ */
+void nvdimm_badblocks_populate(struct nd_region *nd_region,
+ struct badblocks *bb, const struct resource *res)
+{
+ struct nvdimm_bus *nvdimm_bus;
+
+ if (!is_memory(&nd_region->dev)) {
+ dev_WARN_ONCE(&nd_region->dev, 1,
+ "%s only valid for pmem regions\n", __func__);
+ return;
+ }
+ nvdimm_bus = walk_to_nvdimm_bus(&nd_region->dev);
+
+ nvdimm_bus_lock(&nvdimm_bus->dev);
+ badblocks_populate(&nvdimm_bus->badrange, bb, res);
+ nvdimm_bus_unlock(&nvdimm_bus->dev);
+}
+EXPORT_SYMBOL_GPL(nvdimm_badblocks_populate);
@@ -11,6 +11,7 @@
* General Public License for more details.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+#include <linux/libnvdimm.h>
#include <linux/sched/mm.h>
#include <linux/vmalloc.h>
#include <linux/uaccess.h>
@@ -221,7 +222,7 @@ static void nvdimm_account_cleared_poison(struct nvdimm_bus *nvdimm_bus,
phys_addr_t phys, u64 cleared)
{
if (cleared > 0)
- nvdimm_forget_poison(nvdimm_bus, phys, cleared);
+ badrange_forget(&nvdimm_bus->badrange, phys, cleared);
if (cleared > 0 && cleared / 512)
nvdimm_clear_badblocks_regions(nvdimm_bus, phys, cleared);
@@ -344,11 +345,10 @@ struct nvdimm_bus *nvdimm_bus_register(struct device *parent,
return NULL;
INIT_LIST_HEAD(&nvdimm_bus->list);
INIT_LIST_HEAD(&nvdimm_bus->mapping_list);
- INIT_LIST_HEAD(&nvdimm_bus->poison_list);
init_waitqueue_head(&nvdimm_bus->probe_wait);
nvdimm_bus->id = ida_simple_get(&nd_ida, 0, 0, GFP_KERNEL);
mutex_init(&nvdimm_bus->reconfig_mutex);
- spin_lock_init(&nvdimm_bus->poison_lock);
+ badrange_init(&nvdimm_bus->badrange);
if (nvdimm_bus->id < 0) {
kfree(nvdimm_bus);
return NULL;
@@ -395,15 +395,15 @@ static int child_unregister(struct device *dev, void *data)
return 0;
}
-static void free_poison_list(struct list_head *poison_list)
+static void free_badrange_list(struct list_head *badrange_list)
{
- struct nd_poison *pl, *next;
+ struct badrange_entry *be, *next;
- list_for_each_entry_safe(pl, next, poison_list, list) {
- list_del(&pl->list);
- kfree(pl);
+ list_for_each_entry_safe(be, next, badrange_list, list) {
+ list_del(&be->list);
+ kfree(be);
}
- list_del_init(poison_list);
+ list_del_init(badrange_list);
}
static int nd_bus_remove(struct device *dev)
@@ -417,9 +417,9 @@ static int nd_bus_remove(struct device *dev)
nd_synchronize();
device_for_each_child(&nvdimm_bus->dev, NULL, child_unregister);
- spin_lock(&nvdimm_bus->poison_lock);
- free_poison_list(&nvdimm_bus->poison_list);
- spin_unlock(&nvdimm_bus->poison_lock);
+ spin_lock(&nvdimm_bus->badrange.lock);
+ free_badrange_list(&nvdimm_bus->badrange.list);
+ spin_unlock(&nvdimm_bus->badrange.lock);
nvdimm_bus_destroy_ndctl(nvdimm_bus);
@@ -398,265 +398,11 @@ struct attribute_group nvdimm_bus_attribute_group = {
};
EXPORT_SYMBOL_GPL(nvdimm_bus_attribute_group);
-static void set_badblock(struct badblocks *bb, sector_t s, int num)
+int nvdimm_bus_add_badrange(struct nvdimm_bus *nvdimm_bus, u64 addr, u64 length)
{
- dev_dbg(bb->dev, "Found a poison range (0x%llx, 0x%llx)\n",
- (u64) s * 512, (u64) num * 512);
- /* this isn't an error as the hardware will still throw an exception */
- if (badblocks_set(bb, s, num, 1))
- dev_info_once(bb->dev, "%s: failed for sector %llx\n",
- __func__, (u64) s);
+ return badrange_add(&nvdimm_bus->badrange, addr, length);
}
-
-/**
- * __add_badblock_range() - Convert a physical address range to bad sectors
- * @bb: badblocks instance to populate
- * @ns_offset: namespace offset where the error range begins (in bytes)
- * @len: number of bytes of poison to be added
- *
- * This assumes that the range provided with (ns_offset, len) is within
- * the bounds of physical addresses for this namespace, i.e. lies in the
- * interval [ns_start, ns_start + ns_size)
- */
-static void __add_badblock_range(struct badblocks *bb, u64 ns_offset, u64 len)
-{
- const unsigned int sector_size = 512;
- sector_t start_sector, end_sector;
- u64 num_sectors;
- u32 rem;
-
- start_sector = div_u64(ns_offset, sector_size);
- end_sector = div_u64_rem(ns_offset + len, sector_size, &rem);
- if (rem)
- end_sector++;
- num_sectors = end_sector - start_sector;
-
- if (unlikely(num_sectors > (u64)INT_MAX)) {
- u64 remaining = num_sectors;
- sector_t s = start_sector;
-
- while (remaining) {
- int done = min_t(u64, remaining, INT_MAX);
-
- set_badblock(bb, s, done);
- remaining -= done;
- s += done;
- }
- } else
- set_badblock(bb, start_sector, num_sectors);
-}
-
-static void badblocks_populate(struct list_head *poison_list,
- struct badblocks *bb, const struct resource *res)
-{
- struct nd_poison *pl;
-
- if (list_empty(poison_list))
- return;
-
- list_for_each_entry(pl, poison_list, list) {
- u64 pl_end = pl->start + pl->length - 1;
-
- /* Discard intervals with no intersection */
- if (pl_end < res->start)
- continue;
- if (pl->start > res->end)
- continue;
- /* Deal with any overlap after start of the namespace */
- if (pl->start >= res->start) {
- u64 start = pl->start;
- u64 len;
-
- if (pl_end <= res->end)
- len = pl->length;
- else
- len = res->start + resource_size(res)
- - pl->start;
- __add_badblock_range(bb, start - res->start, len);
- continue;
- }
- /* Deal with overlap for poison starting before the namespace */
- if (pl->start < res->start) {
- u64 len;
-
- if (pl_end < res->end)
- len = pl->start + pl->length - res->start;
- else
- len = resource_size(res);
- __add_badblock_range(bb, 0, len);
- }
- }
-}
-
-/**
- * nvdimm_badblocks_populate() - Convert a list of poison ranges to badblocks
- * @region: parent region of the range to interrogate
- * @bb: badblocks instance to populate
- * @res: resource range to consider
- *
- * The poison list generated during bus initialization may contain
- * multiple, possibly overlapping physical address ranges. Compare each
- * of these ranges to the resource range currently being initialized,
- * and add badblocks entries for all matching sub-ranges
- */
-void nvdimm_badblocks_populate(struct nd_region *nd_region,
- struct badblocks *bb, const struct resource *res)
-{
- struct nvdimm_bus *nvdimm_bus;
- struct list_head *poison_list;
-
- if (!is_memory(&nd_region->dev)) {
- dev_WARN_ONCE(&nd_region->dev, 1,
- "%s only valid for pmem regions\n", __func__);
- return;
- }
- nvdimm_bus = walk_to_nvdimm_bus(&nd_region->dev);
- poison_list = &nvdimm_bus->poison_list;
-
- nvdimm_bus_lock(&nvdimm_bus->dev);
- badblocks_populate(poison_list, bb, res);
- nvdimm_bus_unlock(&nvdimm_bus->dev);
-}
-EXPORT_SYMBOL_GPL(nvdimm_badblocks_populate);
-
-static void append_poison_entry(struct nvdimm_bus *nvdimm_bus,
- struct nd_poison *pl, u64 addr, u64 length)
-{
- lockdep_assert_held(&nvdimm_bus->poison_lock);
- pl->start = addr;
- pl->length = length;
- list_add_tail(&pl->list, &nvdimm_bus->poison_list);
-}
-
-static int add_poison(struct nvdimm_bus *nvdimm_bus, u64 addr, u64 length,
- gfp_t flags)
-{
- struct nd_poison *pl;
-
- pl = kzalloc(sizeof(*pl), flags);
- if (!pl)
- return -ENOMEM;
-
- append_poison_entry(nvdimm_bus, pl, addr, length);
- return 0;
-}
-
-static int bus_add_poison(struct nvdimm_bus *nvdimm_bus, u64 addr, u64 length)
-{
- struct nd_poison *pl, *pl_new;
-
- spin_unlock(&nvdimm_bus->poison_lock);
- pl_new = kzalloc(sizeof(*pl_new), GFP_KERNEL);
- spin_lock(&nvdimm_bus->poison_lock);
-
- if (list_empty(&nvdimm_bus->poison_list)) {
- if (!pl_new)
- return -ENOMEM;
- append_poison_entry(nvdimm_bus, pl_new, addr, length);
- return 0;
- }
-
- /*
- * There is a chance this is a duplicate, check for those first.
- * This will be the common case as ARS_STATUS returns all known
- * errors in the SPA space, and we can't query it per region
- */
- list_for_each_entry(pl, &nvdimm_bus->poison_list, list)
- if (pl->start == addr) {
- /* If length has changed, update this list entry */
- if (pl->length != length)
- pl->length = length;
- kfree(pl_new);
- return 0;
- }
-
- /*
- * If not a duplicate or a simple length update, add the entry as is,
- * as any overlapping ranges will get resolved when the list is consumed
- * and converted to badblocks
- */
- if (!pl_new)
- return -ENOMEM;
- append_poison_entry(nvdimm_bus, pl_new, addr, length);
-
- return 0;
-}
-
-int nvdimm_bus_add_poison(struct nvdimm_bus *nvdimm_bus, u64 addr, u64 length)
-{
- int rc;
-
- spin_lock(&nvdimm_bus->poison_lock);
- rc = bus_add_poison(nvdimm_bus, addr, length);
- spin_unlock(&nvdimm_bus->poison_lock);
-
- return rc;
-}
-EXPORT_SYMBOL_GPL(nvdimm_bus_add_poison);
-
-void nvdimm_forget_poison(struct nvdimm_bus *nvdimm_bus, phys_addr_t start,
- unsigned int len)
-{
- struct list_head *poison_list = &nvdimm_bus->poison_list;
- u64 clr_end = start + len - 1;
- struct nd_poison *pl, *next;
-
- spin_lock(&nvdimm_bus->poison_lock);
- WARN_ON_ONCE(list_empty(poison_list));
-
- /*
- * [start, clr_end] is the poison interval being cleared.
- * [pl->start, pl_end] is the poison_list entry we're comparing
- * the above interval against. The poison list entry may need
- * to be modified (update either start or length), deleted, or
- * split into two based on the overlap characteristics
- */
-
- list_for_each_entry_safe(pl, next, poison_list, list) {
- u64 pl_end = pl->start + pl->length - 1;
-
- /* Skip intervals with no intersection */
- if (pl_end < start)
- continue;
- if (pl->start > clr_end)
- continue;
- /* Delete completely overlapped poison entries */
- if ((pl->start >= start) && (pl_end <= clr_end)) {
- list_del(&pl->list);
- kfree(pl);
- continue;
- }
- /* Adjust start point of partially cleared entries */
- if ((start <= pl->start) && (clr_end > pl->start)) {
- pl->length -= clr_end - pl->start + 1;
- pl->start = clr_end + 1;
- continue;
- }
- /* Adjust pl->length for partial clearing at the tail end */
- if ((pl->start < start) && (pl_end <= clr_end)) {
- /* pl->start remains the same */
- pl->length = start - pl->start;
- continue;
- }
- /*
- * If clearing in the middle of an entry, we split it into
- * two by modifying the current entry to represent one half of
- * the split, and adding a new entry for the second half.
- */
- if ((pl->start < start) && (pl_end > clr_end)) {
- u64 new_start = clr_end + 1;
- u64 new_len = pl_end - new_start + 1;
-
- /* Add new entry covering the right half */
- add_poison(nvdimm_bus, new_start, new_len, GFP_NOWAIT);
- /* Adjust this entry to cover the left half */
- pl->length = start - pl->start;
- continue;
- }
- }
- spin_unlock(&nvdimm_bus->poison_lock);
-}
-EXPORT_SYMBOL_GPL(nvdimm_forget_poison);
+EXPORT_SYMBOL_GPL(nvdimm_bus_add_badrange);
#ifdef CONFIG_BLK_DEV_INTEGRITY
int nd_integrity_init(struct gendisk *disk, unsigned long meta_size)
@@ -29,10 +29,9 @@ struct nvdimm_bus {
struct list_head list;
struct device dev;
int id, probe_active;
- struct list_head poison_list;
struct list_head mapping_list;
struct mutex reconfig_mutex;
- spinlock_t poison_lock;
+ struct badrange badrange;
};
struct nvdimm {
@@ -34,12 +34,6 @@ enum {
NVDIMM_IO_ATOMIC = 1,
};
-struct nd_poison {
- u64 start;
- u64 length;
- struct list_head list;
-};
-
struct nvdimm_drvdata {
struct device *dev;
int nslabel_size;
@@ -18,6 +18,18 @@
#include <linux/sizes.h>
#include <linux/types.h>
#include <linux/uuid.h>
+#include <linux/spinlock.h>
+
+struct badrange_entry {
+ u64 start;
+ u64 length;
+ struct list_head list;
+};
+
+struct badrange {
+ struct list_head list;
+ spinlock_t lock;
+};
enum {
/* when a dimm supports both PMEM and BLK access a label is required */
@@ -129,9 +141,12 @@ static inline struct nd_blk_region_desc *to_blk_region_desc(
}
-int nvdimm_bus_add_poison(struct nvdimm_bus *nvdimm_bus, u64 addr, u64 length);
-void nvdimm_forget_poison(struct nvdimm_bus *nvdimm_bus,
- phys_addr_t start, unsigned int len);
+void badrange_init(struct badrange *badrange);
+int badrange_add(struct badrange *badrange, u64 addr, u64 length);
+void badrange_forget(struct badrange *badrange, phys_addr_t start,
+ unsigned int len);
+int nvdimm_bus_add_badrange(struct nvdimm_bus *nvdimm_bus, u64 addr,
+ u64 length);
struct nvdimm_bus *nvdimm_bus_register(struct device *parent,
struct nvdimm_bus_descriptor *nfit_desc);
void nvdimm_bus_unregister(struct nvdimm_bus *nvdimm_bus);