linux/drivers/nvdimm/core.c
Vishal Verma 37b137ff8c nfit, libnvdimm: allow an ARS scrub to be triggered on demand
Normally, an ARS (Address Range Scrub) only happens at
boot/initialization time. There can however arise situations where a
bus-wide rescan is needed - notably, in the case of discovering a latent
media error, we should do a full rescan to figure out what other sectors
are bad, and thus potentially avoid triggering an mce on them in the
future. Also provide a sysfs trigger to start a bus-wide scrub.

Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2016-07-23 21:51:42 -07:00

663 lines
16 KiB
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.
*/
#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"
LIST_HEAD(nvdimm_bus_list);
DEFINE_MUTEX(nvdimm_bus_list_mutex);
void nvdimm_bus_lock(struct device *dev)
{
struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
if (!nvdimm_bus)
return;
mutex_lock(&nvdimm_bus->reconfig_mutex);
}
EXPORT_SYMBOL(nvdimm_bus_lock);
void nvdimm_bus_unlock(struct device *dev)
{
struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
if (!nvdimm_bus)
return;
mutex_unlock(&nvdimm_bus->reconfig_mutex);
}
EXPORT_SYMBOL(nvdimm_bus_unlock);
bool is_nvdimm_bus_locked(struct device *dev)
{
struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
if (!nvdimm_bus)
return false;
return mutex_is_locked(&nvdimm_bus->reconfig_mutex);
}
EXPORT_SYMBOL(is_nvdimm_bus_locked);
struct nvdimm_map {
struct nvdimm_bus *nvdimm_bus;
struct list_head list;
resource_size_t offset;
unsigned long flags;
size_t size;
union {
void *mem;
void __iomem *iomem;
};
struct kref kref;
};
static struct nvdimm_map *find_nvdimm_map(struct device *dev,
resource_size_t offset)
{
struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
struct nvdimm_map *nvdimm_map;
list_for_each_entry(nvdimm_map, &nvdimm_bus->mapping_list, list)
if (nvdimm_map->offset == offset)
return nvdimm_map;
return NULL;
}
static struct nvdimm_map *alloc_nvdimm_map(struct device *dev,
resource_size_t offset, size_t size, unsigned long flags)
{
struct nvdimm_bus *nvdimm_bus = walk_to_nvdimm_bus(dev);
struct nvdimm_map *nvdimm_map;
nvdimm_map = kzalloc(sizeof(*nvdimm_map), GFP_KERNEL);
if (!nvdimm_map)
return NULL;
INIT_LIST_HEAD(&nvdimm_map->list);
nvdimm_map->nvdimm_bus = nvdimm_bus;
nvdimm_map->offset = offset;
nvdimm_map->flags = flags;
nvdimm_map->size = size;
kref_init(&nvdimm_map->kref);
if (!request_mem_region(offset, size, dev_name(&nvdimm_bus->dev)))
goto err_request_region;
if (flags)
nvdimm_map->mem = memremap(offset, size, flags);
else
nvdimm_map->iomem = ioremap(offset, size);
if (!nvdimm_map->mem)
goto err_map;
dev_WARN_ONCE(dev, !is_nvdimm_bus_locked(dev), "%s: bus unlocked!",
__func__);
list_add(&nvdimm_map->list, &nvdimm_bus->mapping_list);
return nvdimm_map;
err_map:
release_mem_region(offset, size);
err_request_region:
kfree(nvdimm_map);
return NULL;
}
static void nvdimm_map_release(struct kref *kref)
{
struct nvdimm_bus *nvdimm_bus;
struct nvdimm_map *nvdimm_map;
nvdimm_map = container_of(kref, struct nvdimm_map, kref);
nvdimm_bus = nvdimm_map->nvdimm_bus;
dev_dbg(&nvdimm_bus->dev, "%s: %pa\n", __func__, &nvdimm_map->offset);
list_del(&nvdimm_map->list);
if (nvdimm_map->flags)
memunmap(nvdimm_map->mem);
else
iounmap(nvdimm_map->iomem);
release_mem_region(nvdimm_map->offset, nvdimm_map->size);
kfree(nvdimm_map);
}
static void nvdimm_map_put(void *data)
{
struct nvdimm_map *nvdimm_map = data;
struct nvdimm_bus *nvdimm_bus = nvdimm_map->nvdimm_bus;
nvdimm_bus_lock(&nvdimm_bus->dev);
kref_put(&nvdimm_map->kref, nvdimm_map_release);
nvdimm_bus_unlock(&nvdimm_bus->dev);
}
/**
* devm_nvdimm_memremap - map a resource that is shared across regions
* @dev: device that will own a reference to the shared mapping
* @offset: physical base address of the mapping
* @size: mapping size
* @flags: memremap flags, or, if zero, perform an ioremap instead
*/
void *devm_nvdimm_memremap(struct device *dev, resource_size_t offset,
size_t size, unsigned long flags)
{
struct nvdimm_map *nvdimm_map;
nvdimm_bus_lock(dev);
nvdimm_map = find_nvdimm_map(dev, offset);
if (!nvdimm_map)
nvdimm_map = alloc_nvdimm_map(dev, offset, size, flags);
else
kref_get(&nvdimm_map->kref);
nvdimm_bus_unlock(dev);
if (devm_add_action_or_reset(dev, nvdimm_map_put, nvdimm_map))
return NULL;
return nvdimm_map->mem;
}
EXPORT_SYMBOL_GPL(devm_nvdimm_memremap);
u64 nd_fletcher64(void *addr, size_t len, bool le)
{
u32 *buf = addr;
u32 lo32 = 0;
u64 hi32 = 0;
int i;
for (i = 0; i < len / sizeof(u32); i++) {
lo32 += le ? le32_to_cpu((__le32) buf[i]) : buf[i];
hi32 += lo32;
}
return hi32 << 32 | lo32;
}
EXPORT_SYMBOL_GPL(nd_fletcher64);
struct nvdimm_bus_descriptor *to_nd_desc(struct nvdimm_bus *nvdimm_bus)
{
/* struct nvdimm_bus definition is private to libnvdimm */
return nvdimm_bus->nd_desc;
}
EXPORT_SYMBOL_GPL(to_nd_desc);
struct device *to_nvdimm_bus_dev(struct nvdimm_bus *nvdimm_bus)
{
/* struct nvdimm_bus definition is private to libnvdimm */
return &nvdimm_bus->dev;
}
EXPORT_SYMBOL_GPL(to_nvdimm_bus_dev);
static bool is_uuid_sep(char sep)
{
if (sep == '\n' || sep == '-' || sep == ':' || sep == '\0')
return true;
return false;
}
static int nd_uuid_parse(struct device *dev, u8 *uuid_out, const char *buf,
size_t len)
{
const char *str = buf;
u8 uuid[16];
int i;
for (i = 0; i < 16; i++) {
if (!isxdigit(str[0]) || !isxdigit(str[1])) {
dev_dbg(dev, "%s: pos: %d buf[%zd]: %c buf[%zd]: %c\n",
__func__, i, str - buf, str[0],
str + 1 - buf, str[1]);
return -EINVAL;
}
uuid[i] = (hex_to_bin(str[0]) << 4) | hex_to_bin(str[1]);
str += 2;
if (is_uuid_sep(*str))
str++;
}
memcpy(uuid_out, uuid, sizeof(uuid));
return 0;
}
/**
* nd_uuid_store: common implementation for writing 'uuid' sysfs attributes
* @dev: container device for the uuid property
* @uuid_out: uuid buffer to replace
* @buf: raw sysfs buffer to parse
*
* Enforce that uuids can only be changed while the device is disabled
* (driver detached)
* LOCKING: expects device_lock() is held on entry
*/
int nd_uuid_store(struct device *dev, u8 **uuid_out, const char *buf,
size_t len)
{
u8 uuid[16];
int rc;
if (dev->driver)
return -EBUSY;
rc = nd_uuid_parse(dev, uuid, buf, len);
if (rc)
return rc;
kfree(*uuid_out);
*uuid_out = kmemdup(uuid, sizeof(uuid), GFP_KERNEL);
if (!(*uuid_out))
return -ENOMEM;
return 0;
}
ssize_t nd_sector_size_show(unsigned long current_lbasize,
const unsigned long *supported, char *buf)
{
ssize_t len = 0;
int i;
for (i = 0; supported[i]; i++)
if (current_lbasize == supported[i])
len += sprintf(buf + len, "[%ld] ", supported[i]);
else
len += sprintf(buf + len, "%ld ", supported[i]);
len += sprintf(buf + len, "\n");
return len;
}
ssize_t nd_sector_size_store(struct device *dev, const char *buf,
unsigned long *current_lbasize, const unsigned long *supported)
{
unsigned long lbasize;
int rc, i;
if (dev->driver)
return -EBUSY;
rc = kstrtoul(buf, 0, &lbasize);
if (rc)
return rc;
for (i = 0; supported[i]; i++)
if (lbasize == supported[i])
break;
if (supported[i]) {
*current_lbasize = lbasize;
return 0;
} else {
return -EINVAL;
}
}
void __nd_iostat_start(struct bio *bio, unsigned long *start)
{
struct gendisk *disk = bio->bi_bdev->bd_disk;
const int rw = bio_data_dir(bio);
int cpu = part_stat_lock();
*start = jiffies;
part_round_stats(cpu, &disk->part0);
part_stat_inc(cpu, &disk->part0, ios[rw]);
part_stat_add(cpu, &disk->part0, sectors[rw], bio_sectors(bio));
part_inc_in_flight(&disk->part0, rw);
part_stat_unlock();
}
EXPORT_SYMBOL(__nd_iostat_start);
void nd_iostat_end(struct bio *bio, unsigned long start)
{
struct gendisk *disk = bio->bi_bdev->bd_disk;
unsigned long duration = jiffies - start;
const int rw = bio_data_dir(bio);
int cpu = part_stat_lock();
part_stat_add(cpu, &disk->part0, ticks[rw], duration);
part_round_stats(cpu, &disk->part0);
part_dec_in_flight(&disk->part0, rw);
part_stat_unlock();
}
EXPORT_SYMBOL(nd_iostat_end);
static ssize_t commands_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
int cmd, len = 0;
struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
for_each_set_bit(cmd, &nd_desc->cmd_mask, BITS_PER_LONG)
len += sprintf(buf + len, "%s ", nvdimm_bus_cmd_name(cmd));
len += sprintf(buf + len, "\n");
return len;
}
static DEVICE_ATTR_RO(commands);
static const char *nvdimm_bus_provider(struct nvdimm_bus *nvdimm_bus)
{
struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
struct device *parent = nvdimm_bus->dev.parent;
if (nd_desc->provider_name)
return nd_desc->provider_name;
else if (parent)
return dev_name(parent);
else
return "unknown";
}
static ssize_t provider_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
return sprintf(buf, "%s\n", nvdimm_bus_provider(nvdimm_bus));
}
static DEVICE_ATTR_RO(provider);
static int flush_namespaces(struct device *dev, void *data)
{
device_lock(dev);
device_unlock(dev);
return 0;
}
static int flush_regions_dimms(struct device *dev, void *data)
{
device_lock(dev);
device_unlock(dev);
device_for_each_child(dev, NULL, flush_namespaces);
return 0;
}
static ssize_t wait_probe_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct nvdimm_bus *nvdimm_bus = to_nvdimm_bus(dev);
struct nvdimm_bus_descriptor *nd_desc = nvdimm_bus->nd_desc;
int rc;
if (nd_desc->flush_probe) {
rc = nd_desc->flush_probe(nd_desc);
if (rc)
return rc;
}
nd_synchronize();
device_for_each_child(dev, NULL, flush_regions_dimms);
return sprintf(buf, "1\n");
}
static DEVICE_ATTR_RO(wait_probe);
static struct attribute *nvdimm_bus_attributes[] = {
&dev_attr_commands.attr,
&dev_attr_wait_probe.attr,
&dev_attr_provider.attr,
NULL,
};
struct attribute_group nvdimm_bus_attribute_group = {
.attrs = nvdimm_bus_attributes,
};
EXPORT_SYMBOL_GPL(nvdimm_bus_attribute_group);
static void set_badblock(struct badblocks *bb, sector_t s, int num)
{
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);
}
/**
* __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;
u64 num_sectors;
u32 rem;
start_sector = div_u64(ns_offset, sector_size);
num_sectors = div_u64_rem(len, sector_size, &rem);
if (rem)
num_sectors++;
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_nd_pmem(&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 int add_poison(struct nvdimm_bus *nvdimm_bus, u64 addr, u64 length)
{
struct nd_poison *pl;
pl = kzalloc(sizeof(*pl), GFP_KERNEL);
if (!pl)
return -ENOMEM;
pl->start = addr;
pl->length = length;
list_add_tail(&pl->list, &nvdimm_bus->poison_list);
return 0;
}
static int bus_add_poison(struct nvdimm_bus *nvdimm_bus, u64 addr, u64 length)
{
struct nd_poison *pl;
if (list_empty(&nvdimm_bus->poison_list))
return add_poison(nvdimm_bus, addr, length);
/*
* 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;
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
*/
return add_poison(nvdimm_bus, addr, length);
}
int nvdimm_bus_add_poison(struct nvdimm_bus *nvdimm_bus, u64 addr, u64 length)
{
int rc;
nvdimm_bus_lock(&nvdimm_bus->dev);
rc = bus_add_poison(nvdimm_bus, addr, length);
nvdimm_bus_unlock(&nvdimm_bus->dev);
return rc;
}
EXPORT_SYMBOL_GPL(nvdimm_bus_add_poison);
#ifdef CONFIG_BLK_DEV_INTEGRITY
int nd_integrity_init(struct gendisk *disk, unsigned long meta_size)
{
struct blk_integrity bi;
if (meta_size == 0)
return 0;
memset(&bi, 0, sizeof(bi));
bi.tuple_size = meta_size;
bi.tag_size = meta_size;
blk_integrity_register(disk, &bi);
blk_queue_max_integrity_segments(disk->queue, 1);
return 0;
}
EXPORT_SYMBOL(nd_integrity_init);
#else /* CONFIG_BLK_DEV_INTEGRITY */
int nd_integrity_init(struct gendisk *disk, unsigned long meta_size)
{
return 0;
}
EXPORT_SYMBOL(nd_integrity_init);
#endif
static __init int libnvdimm_init(void)
{
int rc;
rc = nvdimm_bus_init();
if (rc)
return rc;
rc = nvdimm_init();
if (rc)
goto err_dimm;
rc = nd_region_init();
if (rc)
goto err_region;
return 0;
err_region:
nvdimm_exit();
err_dimm:
nvdimm_bus_exit();
return rc;
}
static __exit void libnvdimm_exit(void)
{
WARN_ON(!list_empty(&nvdimm_bus_list));
nd_region_exit();
nvdimm_exit();
nvdimm_bus_exit();
nd_region_devs_exit();
nvdimm_devs_exit();
}
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Intel Corporation");
subsys_initcall(libnvdimm_init);
module_exit(libnvdimm_exit);