// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright(c) 2017 Intel Corporation. All rights reserved.
*/
#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 *bre, u64 addr, u64 length)
{
lockdep_assert_held(&badrange->lock);
bre->start = addr;
bre->length = length;
list_add_tail(&bre->list, &badrange->list);
}
static int alloc_and_append_badrange_entry(struct badrange *badrange,
u64 addr, u64 length, gfp_t flags)
{
struct badrange_entry *bre;
bre = kzalloc(sizeof(*bre), flags);
if (!bre)
return -ENOMEM;
append_badrange_entry(badrange, bre, addr, length);
return 0;
}
static int add_badrange(struct badrange *badrange, u64 addr, u64 length)
{
struct badrange_entry *bre, *bre_new;
spin_unlock(&badrange->lock);
bre_new = kzalloc(sizeof(*bre_new), GFP_KERNEL);
spin_lock(&badrange->lock);
if (list_empty(&badrange->list)) {
if (!bre_new)
return -ENOMEM;
append_badrange_entry(badrange, bre_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(bre, &badrange->list, list)
if (bre->start == addr) {
/* If length has changed, update this list entry */
if (bre->length != length)
bre->length = length;
kfree(bre_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 (!bre_new)
return -ENOMEM;
append_badrange_entry(badrange, bre_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 *bre, *next;
spin_lock(&badrange->lock);
/*
* [start, clr_end] is the badrange interval being cleared.
* [bre->start, bre_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(bre, next, badrange_list, list) {
u64 bre_end = bre->start + bre->length - 1;
/* Skip intervals with no intersection */
if (bre_end < start)
continue;
if (bre->start > clr_end)
continue;
/* Delete completely overlapped badrange entries */
if ((bre->start >= start) && (bre_end <= clr_end)) {
list_del(&bre->list);
kfree(bre);
continue;
}
/* Adjust start point of partially cleared entries */
if ((start <= bre->start) && (clr_end > bre->start)) {
bre->length -= clr_end - bre->start + 1;
bre->start = clr_end + 1;
continue;
}
/* Adjust bre->length for partial clearing at the tail end */
if ((bre->start < start) && (bre_end <= clr_end)) {
/* bre->start remains the same */
bre->length = start - bre->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 ((bre->start < start) && (bre_end > clr_end)) {
u64 new_start = clr_end + 1;
u64 new_len = bre_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 */
bre->length = start - bre->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 range *range)
{
struct badrange_entry *bre;
if (list_empty(&badrange->list))
return;
list_for_each_entry(bre, &badrange->list, list) {
u64 bre_end = bre->start + bre->length - 1;
/* Discard intervals with no intersection */
if (bre_end < range->start)
continue;
if (bre->start > range->end)
continue;
/* Deal with any overlap after start of the namespace */
if (bre->start >= range->start) {
u64 start = bre->start;
u64 len;
if (bre_end <= range->end)
len = bre->length;
else
len = range->start + range_len(range)
- bre->start;
__add_badblock_range(bb, start - range->start, len);
continue;
}
/*
* Deal with overlap for badrange starting before
* the namespace.
*/
if (bre->start < range->start) {
u64 len;
if (bre_end < range->end)
len = bre->start + bre->length - range->start;
else
len = range_len(range);
__add_badblock_range(bb, 0, len);
}
}
}
/**
* nvdimm_badblocks_populate() - Convert a list of badranges to badblocks
* @nd_region: parent region of the range to interrogate
* @bb: badblocks instance to populate
* @range: 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 range *range)
{
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, range);
nvdimm_bus_unlock(&nvdimm_bus->dev);
}
EXPORT_SYMBOL_GPL(nvdimm_badblocks_populate);
Codebase Browser
linux