1113a7e92e
This is a fix to the device-mapper-log-bitset-fix-endian patch that switched to ext2_* versions of the set and clear bit functions. The find_next_zero_bit function also has to be the ext2 one. Otherwise the mirror target tries to recover non-existent regions beyond the end of device. Signed-off-by: Stefan Bader <shbader@de.ibm.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
689 lines
15 KiB
C
689 lines
15 KiB
C
/*
|
|
* Copyright (C) 2003 Sistina Software
|
|
*
|
|
* This file is released under the LGPL.
|
|
*/
|
|
|
|
#include <linux/init.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/module.h>
|
|
#include <linux/vmalloc.h>
|
|
|
|
#include "dm-log.h"
|
|
#include "dm-io.h"
|
|
|
|
static LIST_HEAD(_log_types);
|
|
static DEFINE_SPINLOCK(_lock);
|
|
|
|
int dm_register_dirty_log_type(struct dirty_log_type *type)
|
|
{
|
|
spin_lock(&_lock);
|
|
type->use_count = 0;
|
|
list_add(&type->list, &_log_types);
|
|
spin_unlock(&_lock);
|
|
|
|
return 0;
|
|
}
|
|
|
|
int dm_unregister_dirty_log_type(struct dirty_log_type *type)
|
|
{
|
|
spin_lock(&_lock);
|
|
|
|
if (type->use_count)
|
|
DMWARN("Attempt to unregister a log type that is still in use");
|
|
else
|
|
list_del(&type->list);
|
|
|
|
spin_unlock(&_lock);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct dirty_log_type *get_type(const char *type_name)
|
|
{
|
|
struct dirty_log_type *type;
|
|
|
|
spin_lock(&_lock);
|
|
list_for_each_entry (type, &_log_types, list)
|
|
if (!strcmp(type_name, type->name)) {
|
|
if (!type->use_count && !try_module_get(type->module)){
|
|
spin_unlock(&_lock);
|
|
return NULL;
|
|
}
|
|
type->use_count++;
|
|
spin_unlock(&_lock);
|
|
return type;
|
|
}
|
|
|
|
spin_unlock(&_lock);
|
|
return NULL;
|
|
}
|
|
|
|
static void put_type(struct dirty_log_type *type)
|
|
{
|
|
spin_lock(&_lock);
|
|
if (!--type->use_count)
|
|
module_put(type->module);
|
|
spin_unlock(&_lock);
|
|
}
|
|
|
|
struct dirty_log *dm_create_dirty_log(const char *type_name, struct dm_target *ti,
|
|
unsigned int argc, char **argv)
|
|
{
|
|
struct dirty_log_type *type;
|
|
struct dirty_log *log;
|
|
|
|
log = kmalloc(sizeof(*log), GFP_KERNEL);
|
|
if (!log)
|
|
return NULL;
|
|
|
|
type = get_type(type_name);
|
|
if (!type) {
|
|
kfree(log);
|
|
return NULL;
|
|
}
|
|
|
|
log->type = type;
|
|
if (type->ctr(log, ti, argc, argv)) {
|
|
kfree(log);
|
|
put_type(type);
|
|
return NULL;
|
|
}
|
|
|
|
return log;
|
|
}
|
|
|
|
void dm_destroy_dirty_log(struct dirty_log *log)
|
|
{
|
|
log->type->dtr(log);
|
|
put_type(log->type);
|
|
kfree(log);
|
|
}
|
|
|
|
/*-----------------------------------------------------------------
|
|
* Persistent and core logs share a lot of their implementation.
|
|
* FIXME: need a reload method to be called from a resume
|
|
*---------------------------------------------------------------*/
|
|
/*
|
|
* Magic for persistent mirrors: "MiRr"
|
|
*/
|
|
#define MIRROR_MAGIC 0x4D695272
|
|
|
|
/*
|
|
* The on-disk version of the metadata.
|
|
*/
|
|
#define MIRROR_DISK_VERSION 2
|
|
#define LOG_OFFSET 2
|
|
|
|
struct log_header {
|
|
uint32_t magic;
|
|
|
|
/*
|
|
* Simple, incrementing version. no backward
|
|
* compatibility.
|
|
*/
|
|
uint32_t version;
|
|
sector_t nr_regions;
|
|
};
|
|
|
|
struct log_c {
|
|
struct dm_target *ti;
|
|
int touched;
|
|
uint32_t region_size;
|
|
unsigned int region_count;
|
|
region_t sync_count;
|
|
|
|
unsigned bitset_uint32_count;
|
|
uint32_t *clean_bits;
|
|
uint32_t *sync_bits;
|
|
uint32_t *recovering_bits; /* FIXME: this seems excessive */
|
|
|
|
int sync_search;
|
|
|
|
/* Resync flag */
|
|
enum sync {
|
|
DEFAULTSYNC, /* Synchronize if necessary */
|
|
NOSYNC, /* Devices known to be already in sync */
|
|
FORCESYNC, /* Force a sync to happen */
|
|
} sync;
|
|
|
|
/*
|
|
* Disk log fields
|
|
*/
|
|
struct dm_dev *log_dev;
|
|
struct log_header header;
|
|
|
|
struct io_region header_location;
|
|
struct log_header *disk_header;
|
|
|
|
struct io_region bits_location;
|
|
};
|
|
|
|
/*
|
|
* The touched member needs to be updated every time we access
|
|
* one of the bitsets.
|
|
*/
|
|
static inline int log_test_bit(uint32_t *bs, unsigned bit)
|
|
{
|
|
return ext2_test_bit(bit, (unsigned long *) bs) ? 1 : 0;
|
|
}
|
|
|
|
static inline void log_set_bit(struct log_c *l,
|
|
uint32_t *bs, unsigned bit)
|
|
{
|
|
ext2_set_bit(bit, (unsigned long *) bs);
|
|
l->touched = 1;
|
|
}
|
|
|
|
static inline void log_clear_bit(struct log_c *l,
|
|
uint32_t *bs, unsigned bit)
|
|
{
|
|
ext2_clear_bit(bit, (unsigned long *) bs);
|
|
l->touched = 1;
|
|
}
|
|
|
|
/*----------------------------------------------------------------
|
|
* Header IO
|
|
*--------------------------------------------------------------*/
|
|
static void header_to_disk(struct log_header *core, struct log_header *disk)
|
|
{
|
|
disk->magic = cpu_to_le32(core->magic);
|
|
disk->version = cpu_to_le32(core->version);
|
|
disk->nr_regions = cpu_to_le64(core->nr_regions);
|
|
}
|
|
|
|
static void header_from_disk(struct log_header *core, struct log_header *disk)
|
|
{
|
|
core->magic = le32_to_cpu(disk->magic);
|
|
core->version = le32_to_cpu(disk->version);
|
|
core->nr_regions = le64_to_cpu(disk->nr_regions);
|
|
}
|
|
|
|
static int read_header(struct log_c *log)
|
|
{
|
|
int r;
|
|
unsigned long ebits;
|
|
|
|
r = dm_io_sync_vm(1, &log->header_location, READ,
|
|
log->disk_header, &ebits);
|
|
if (r)
|
|
return r;
|
|
|
|
header_from_disk(&log->header, log->disk_header);
|
|
|
|
/* New log required? */
|
|
if (log->sync != DEFAULTSYNC || log->header.magic != MIRROR_MAGIC) {
|
|
log->header.magic = MIRROR_MAGIC;
|
|
log->header.version = MIRROR_DISK_VERSION;
|
|
log->header.nr_regions = 0;
|
|
}
|
|
|
|
#ifdef __LITTLE_ENDIAN
|
|
if (log->header.version == 1)
|
|
log->header.version = 2;
|
|
#endif
|
|
|
|
if (log->header.version != MIRROR_DISK_VERSION) {
|
|
DMWARN("incompatible disk log version");
|
|
return -EINVAL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static inline int write_header(struct log_c *log)
|
|
{
|
|
unsigned long ebits;
|
|
|
|
header_to_disk(&log->header, log->disk_header);
|
|
return dm_io_sync_vm(1, &log->header_location, WRITE,
|
|
log->disk_header, &ebits);
|
|
}
|
|
|
|
/*----------------------------------------------------------------
|
|
* Bits IO
|
|
*--------------------------------------------------------------*/
|
|
static int read_bits(struct log_c *log)
|
|
{
|
|
int r;
|
|
unsigned long ebits;
|
|
|
|
r = dm_io_sync_vm(1, &log->bits_location, READ,
|
|
log->clean_bits, &ebits);
|
|
if (r)
|
|
return r;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int write_bits(struct log_c *log)
|
|
{
|
|
unsigned long ebits;
|
|
return dm_io_sync_vm(1, &log->bits_location, WRITE,
|
|
log->clean_bits, &ebits);
|
|
}
|
|
|
|
/*----------------------------------------------------------------
|
|
* core log constructor/destructor
|
|
*
|
|
* argv contains region_size followed optionally by [no]sync
|
|
*--------------------------------------------------------------*/
|
|
#define BYTE_SHIFT 3
|
|
static int core_ctr(struct dirty_log *log, struct dm_target *ti,
|
|
unsigned int argc, char **argv)
|
|
{
|
|
enum sync sync = DEFAULTSYNC;
|
|
|
|
struct log_c *lc;
|
|
uint32_t region_size;
|
|
unsigned int region_count;
|
|
size_t bitset_size;
|
|
|
|
if (argc < 1 || argc > 2) {
|
|
DMWARN("wrong number of arguments to mirror log");
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (argc > 1) {
|
|
if (!strcmp(argv[1], "sync"))
|
|
sync = FORCESYNC;
|
|
else if (!strcmp(argv[1], "nosync"))
|
|
sync = NOSYNC;
|
|
else {
|
|
DMWARN("unrecognised sync argument to mirror log: %s",
|
|
argv[1]);
|
|
return -EINVAL;
|
|
}
|
|
}
|
|
|
|
if (sscanf(argv[0], "%u", ®ion_size) != 1) {
|
|
DMWARN("invalid region size string");
|
|
return -EINVAL;
|
|
}
|
|
|
|
region_count = dm_sector_div_up(ti->len, region_size);
|
|
|
|
lc = kmalloc(sizeof(*lc), GFP_KERNEL);
|
|
if (!lc) {
|
|
DMWARN("couldn't allocate core log");
|
|
return -ENOMEM;
|
|
}
|
|
|
|
lc->ti = ti;
|
|
lc->touched = 0;
|
|
lc->region_size = region_size;
|
|
lc->region_count = region_count;
|
|
lc->sync = sync;
|
|
|
|
/*
|
|
* Work out how many "unsigned long"s we need to hold the bitset.
|
|
*/
|
|
bitset_size = dm_round_up(region_count,
|
|
sizeof(unsigned long) << BYTE_SHIFT);
|
|
bitset_size >>= BYTE_SHIFT;
|
|
|
|
lc->bitset_uint32_count = bitset_size / 4;
|
|
lc->clean_bits = vmalloc(bitset_size);
|
|
if (!lc->clean_bits) {
|
|
DMWARN("couldn't allocate clean bitset");
|
|
kfree(lc);
|
|
return -ENOMEM;
|
|
}
|
|
memset(lc->clean_bits, -1, bitset_size);
|
|
|
|
lc->sync_bits = vmalloc(bitset_size);
|
|
if (!lc->sync_bits) {
|
|
DMWARN("couldn't allocate sync bitset");
|
|
vfree(lc->clean_bits);
|
|
kfree(lc);
|
|
return -ENOMEM;
|
|
}
|
|
memset(lc->sync_bits, (sync == NOSYNC) ? -1 : 0, bitset_size);
|
|
lc->sync_count = (sync == NOSYNC) ? region_count : 0;
|
|
|
|
lc->recovering_bits = vmalloc(bitset_size);
|
|
if (!lc->recovering_bits) {
|
|
DMWARN("couldn't allocate sync bitset");
|
|
vfree(lc->sync_bits);
|
|
vfree(lc->clean_bits);
|
|
kfree(lc);
|
|
return -ENOMEM;
|
|
}
|
|
memset(lc->recovering_bits, 0, bitset_size);
|
|
lc->sync_search = 0;
|
|
log->context = lc;
|
|
return 0;
|
|
}
|
|
|
|
static void core_dtr(struct dirty_log *log)
|
|
{
|
|
struct log_c *lc = (struct log_c *) log->context;
|
|
vfree(lc->clean_bits);
|
|
vfree(lc->sync_bits);
|
|
vfree(lc->recovering_bits);
|
|
kfree(lc);
|
|
}
|
|
|
|
/*----------------------------------------------------------------
|
|
* disk log constructor/destructor
|
|
*
|
|
* argv contains log_device region_size followed optionally by [no]sync
|
|
*--------------------------------------------------------------*/
|
|
static int disk_ctr(struct dirty_log *log, struct dm_target *ti,
|
|
unsigned int argc, char **argv)
|
|
{
|
|
int r;
|
|
size_t size;
|
|
struct log_c *lc;
|
|
struct dm_dev *dev;
|
|
|
|
if (argc < 2 || argc > 3) {
|
|
DMWARN("wrong number of arguments to disk mirror log");
|
|
return -EINVAL;
|
|
}
|
|
|
|
r = dm_get_device(ti, argv[0], 0, 0 /* FIXME */,
|
|
FMODE_READ | FMODE_WRITE, &dev);
|
|
if (r)
|
|
return r;
|
|
|
|
r = core_ctr(log, ti, argc - 1, argv + 1);
|
|
if (r) {
|
|
dm_put_device(ti, dev);
|
|
return r;
|
|
}
|
|
|
|
lc = (struct log_c *) log->context;
|
|
lc->log_dev = dev;
|
|
|
|
/* setup the disk header fields */
|
|
lc->header_location.bdev = lc->log_dev->bdev;
|
|
lc->header_location.sector = 0;
|
|
lc->header_location.count = 1;
|
|
|
|
/*
|
|
* We can't read less than this amount, even though we'll
|
|
* not be using most of this space.
|
|
*/
|
|
lc->disk_header = vmalloc(1 << SECTOR_SHIFT);
|
|
if (!lc->disk_header)
|
|
goto bad;
|
|
|
|
/* setup the disk bitset fields */
|
|
lc->bits_location.bdev = lc->log_dev->bdev;
|
|
lc->bits_location.sector = LOG_OFFSET;
|
|
|
|
size = dm_round_up(lc->bitset_uint32_count * sizeof(uint32_t),
|
|
1 << SECTOR_SHIFT);
|
|
lc->bits_location.count = size >> SECTOR_SHIFT;
|
|
return 0;
|
|
|
|
bad:
|
|
dm_put_device(ti, lc->log_dev);
|
|
core_dtr(log);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
static void disk_dtr(struct dirty_log *log)
|
|
{
|
|
struct log_c *lc = (struct log_c *) log->context;
|
|
dm_put_device(lc->ti, lc->log_dev);
|
|
vfree(lc->disk_header);
|
|
core_dtr(log);
|
|
}
|
|
|
|
static int count_bits32(uint32_t *addr, unsigned size)
|
|
{
|
|
int count = 0, i;
|
|
|
|
for (i = 0; i < size; i++) {
|
|
count += hweight32(*(addr+i));
|
|
}
|
|
return count;
|
|
}
|
|
|
|
static int disk_resume(struct dirty_log *log)
|
|
{
|
|
int r;
|
|
unsigned i;
|
|
struct log_c *lc = (struct log_c *) log->context;
|
|
size_t size = lc->bitset_uint32_count * sizeof(uint32_t);
|
|
|
|
/* read the disk header */
|
|
r = read_header(lc);
|
|
if (r)
|
|
return r;
|
|
|
|
/* read the bits */
|
|
r = read_bits(lc);
|
|
if (r)
|
|
return r;
|
|
|
|
/* set or clear any new bits */
|
|
if (lc->sync == NOSYNC)
|
|
for (i = lc->header.nr_regions; i < lc->region_count; i++)
|
|
/* FIXME: amazingly inefficient */
|
|
log_set_bit(lc, lc->clean_bits, i);
|
|
else
|
|
for (i = lc->header.nr_regions; i < lc->region_count; i++)
|
|
/* FIXME: amazingly inefficient */
|
|
log_clear_bit(lc, lc->clean_bits, i);
|
|
|
|
/* copy clean across to sync */
|
|
memcpy(lc->sync_bits, lc->clean_bits, size);
|
|
lc->sync_count = count_bits32(lc->clean_bits, lc->bitset_uint32_count);
|
|
|
|
/* write the bits */
|
|
r = write_bits(lc);
|
|
if (r)
|
|
return r;
|
|
|
|
/* set the correct number of regions in the header */
|
|
lc->header.nr_regions = lc->region_count;
|
|
|
|
/* write the new header */
|
|
return write_header(lc);
|
|
}
|
|
|
|
static uint32_t core_get_region_size(struct dirty_log *log)
|
|
{
|
|
struct log_c *lc = (struct log_c *) log->context;
|
|
return lc->region_size;
|
|
}
|
|
|
|
static int core_is_clean(struct dirty_log *log, region_t region)
|
|
{
|
|
struct log_c *lc = (struct log_c *) log->context;
|
|
return log_test_bit(lc->clean_bits, region);
|
|
}
|
|
|
|
static int core_in_sync(struct dirty_log *log, region_t region, int block)
|
|
{
|
|
struct log_c *lc = (struct log_c *) log->context;
|
|
return log_test_bit(lc->sync_bits, region);
|
|
}
|
|
|
|
static int core_flush(struct dirty_log *log)
|
|
{
|
|
/* no op */
|
|
return 0;
|
|
}
|
|
|
|
static int disk_flush(struct dirty_log *log)
|
|
{
|
|
int r;
|
|
struct log_c *lc = (struct log_c *) log->context;
|
|
|
|
/* only write if the log has changed */
|
|
if (!lc->touched)
|
|
return 0;
|
|
|
|
r = write_bits(lc);
|
|
if (!r)
|
|
lc->touched = 0;
|
|
|
|
return r;
|
|
}
|
|
|
|
static void core_mark_region(struct dirty_log *log, region_t region)
|
|
{
|
|
struct log_c *lc = (struct log_c *) log->context;
|
|
log_clear_bit(lc, lc->clean_bits, region);
|
|
}
|
|
|
|
static void core_clear_region(struct dirty_log *log, region_t region)
|
|
{
|
|
struct log_c *lc = (struct log_c *) log->context;
|
|
log_set_bit(lc, lc->clean_bits, region);
|
|
}
|
|
|
|
static int core_get_resync_work(struct dirty_log *log, region_t *region)
|
|
{
|
|
struct log_c *lc = (struct log_c *) log->context;
|
|
|
|
if (lc->sync_search >= lc->region_count)
|
|
return 0;
|
|
|
|
do {
|
|
*region = ext2_find_next_zero_bit(
|
|
(unsigned long *) lc->sync_bits,
|
|
lc->region_count,
|
|
lc->sync_search);
|
|
lc->sync_search = *region + 1;
|
|
|
|
if (*region >= lc->region_count)
|
|
return 0;
|
|
|
|
} while (log_test_bit(lc->recovering_bits, *region));
|
|
|
|
log_set_bit(lc, lc->recovering_bits, *region);
|
|
return 1;
|
|
}
|
|
|
|
static void core_complete_resync_work(struct dirty_log *log, region_t region,
|
|
int success)
|
|
{
|
|
struct log_c *lc = (struct log_c *) log->context;
|
|
|
|
log_clear_bit(lc, lc->recovering_bits, region);
|
|
if (success) {
|
|
log_set_bit(lc, lc->sync_bits, region);
|
|
lc->sync_count++;
|
|
}
|
|
}
|
|
|
|
static region_t core_get_sync_count(struct dirty_log *log)
|
|
{
|
|
struct log_c *lc = (struct log_c *) log->context;
|
|
|
|
return lc->sync_count;
|
|
}
|
|
|
|
#define DMEMIT_SYNC \
|
|
if (lc->sync != DEFAULTSYNC) \
|
|
DMEMIT("%ssync ", lc->sync == NOSYNC ? "no" : "")
|
|
|
|
static int core_status(struct dirty_log *log, status_type_t status,
|
|
char *result, unsigned int maxlen)
|
|
{
|
|
int sz = 0;
|
|
struct log_c *lc = log->context;
|
|
|
|
switch(status) {
|
|
case STATUSTYPE_INFO:
|
|
break;
|
|
|
|
case STATUSTYPE_TABLE:
|
|
DMEMIT("%s %u %u ", log->type->name,
|
|
lc->sync == DEFAULTSYNC ? 1 : 2, lc->region_size);
|
|
DMEMIT_SYNC;
|
|
}
|
|
|
|
return sz;
|
|
}
|
|
|
|
static int disk_status(struct dirty_log *log, status_type_t status,
|
|
char *result, unsigned int maxlen)
|
|
{
|
|
int sz = 0;
|
|
char buffer[16];
|
|
struct log_c *lc = log->context;
|
|
|
|
switch(status) {
|
|
case STATUSTYPE_INFO:
|
|
break;
|
|
|
|
case STATUSTYPE_TABLE:
|
|
format_dev_t(buffer, lc->log_dev->bdev->bd_dev);
|
|
DMEMIT("%s %u %s %u ", log->type->name,
|
|
lc->sync == DEFAULTSYNC ? 2 : 3, buffer,
|
|
lc->region_size);
|
|
DMEMIT_SYNC;
|
|
}
|
|
|
|
return sz;
|
|
}
|
|
|
|
static struct dirty_log_type _core_type = {
|
|
.name = "core",
|
|
.module = THIS_MODULE,
|
|
.ctr = core_ctr,
|
|
.dtr = core_dtr,
|
|
.get_region_size = core_get_region_size,
|
|
.is_clean = core_is_clean,
|
|
.in_sync = core_in_sync,
|
|
.flush = core_flush,
|
|
.mark_region = core_mark_region,
|
|
.clear_region = core_clear_region,
|
|
.get_resync_work = core_get_resync_work,
|
|
.complete_resync_work = core_complete_resync_work,
|
|
.get_sync_count = core_get_sync_count,
|
|
.status = core_status,
|
|
};
|
|
|
|
static struct dirty_log_type _disk_type = {
|
|
.name = "disk",
|
|
.module = THIS_MODULE,
|
|
.ctr = disk_ctr,
|
|
.dtr = disk_dtr,
|
|
.suspend = disk_flush,
|
|
.resume = disk_resume,
|
|
.get_region_size = core_get_region_size,
|
|
.is_clean = core_is_clean,
|
|
.in_sync = core_in_sync,
|
|
.flush = disk_flush,
|
|
.mark_region = core_mark_region,
|
|
.clear_region = core_clear_region,
|
|
.get_resync_work = core_get_resync_work,
|
|
.complete_resync_work = core_complete_resync_work,
|
|
.get_sync_count = core_get_sync_count,
|
|
.status = disk_status,
|
|
};
|
|
|
|
int __init dm_dirty_log_init(void)
|
|
{
|
|
int r;
|
|
|
|
r = dm_register_dirty_log_type(&_core_type);
|
|
if (r)
|
|
DMWARN("couldn't register core log");
|
|
|
|
r = dm_register_dirty_log_type(&_disk_type);
|
|
if (r) {
|
|
DMWARN("couldn't register disk type");
|
|
dm_unregister_dirty_log_type(&_core_type);
|
|
}
|
|
|
|
return r;
|
|
}
|
|
|
|
void dm_dirty_log_exit(void)
|
|
{
|
|
dm_unregister_dirty_log_type(&_disk_type);
|
|
dm_unregister_dirty_log_type(&_core_type);
|
|
}
|
|
|
|
EXPORT_SYMBOL(dm_register_dirty_log_type);
|
|
EXPORT_SYMBOL(dm_unregister_dirty_log_type);
|
|
EXPORT_SYMBOL(dm_create_dirty_log);
|
|
EXPORT_SYMBOL(dm_destroy_dirty_log);
|