#include <linux/slab.h>
#include <linux/module.h>
#include <linux/vmalloc.h>
+#include <linux/dm-io.h>
+#include <linux/dm-dirty-log.h>
-#include "dm-log.h"
-#include "dm-io.h"
-#include "dm.h"
+#include <linux/device-mapper.h>
#define DM_MSG_PREFIX "dirty region log"
static LIST_HEAD(_log_types);
static DEFINE_SPINLOCK(_lock);
-static struct dm_dirty_log_type *_get_type(const char *type_name)
+static struct dm_dirty_log_type *__find_dirty_log_type(const char *name)
{
- struct dm_dirty_log_type *type;
+ struct dm_dirty_log_type *log_type;
+
+ list_for_each_entry(log_type, &_log_types, list)
+ if (!strcmp(name, log_type->name))
+ return log_type;
+
+ return NULL;
+}
+
+static struct dm_dirty_log_type *_get_dirty_log_type(const char *name)
+{
+ struct dm_dirty_log_type *log_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;
- }
+
+ log_type = __find_dirty_log_type(name);
+ if (log_type && !try_module_get(log_type->module))
+ log_type = NULL;
spin_unlock(&_lock);
- return NULL;
+
+ return log_type;
}
/*
* get_type
* @type_name
*
- * Attempt to retrieve the dirty_log_type by name. If not already
+ * Attempt to retrieve the dm_dirty_log_type by name. If not already
* available, attempt to load the appropriate module.
*
* Log modules are named "dm-log-" followed by the 'type_name'.
static struct dm_dirty_log_type *get_type(const char *type_name)
{
char *p, *type_name_dup;
- struct dm_dirty_log_type *type;
+ struct dm_dirty_log_type *log_type;
+
+ if (!type_name)
+ return NULL;
- type = _get_type(type_name);
- if (type)
- return type;
+ log_type = _get_dirty_log_type(type_name);
+ if (log_type)
+ return log_type;
type_name_dup = kstrdup(type_name, GFP_KERNEL);
if (!type_name_dup) {
}
while (request_module("dm-log-%s", type_name_dup) ||
- !(type = _get_type(type_name))) {
+ !(log_type = _get_dirty_log_type(type_name))) {
p = strrchr(type_name_dup, '-');
if (!p)
break;
p[0] = '\0';
}
- if (!type)
+ if (!log_type)
DMWARN("Module for logging type \"%s\" not found.", type_name);
kfree(type_name_dup);
- return type;
+ return log_type;
}
static void put_type(struct dm_dirty_log_type *type)
{
+ if (!type)
+ return;
+
spin_lock(&_lock);
- if (!--type->use_count)
- module_put(type->module);
+ if (!__find_dirty_log_type(type->name))
+ goto out;
+
+ module_put(type->module);
+
+out:
spin_unlock(&_lock);
}
int dm_dirty_log_type_register(struct dm_dirty_log_type *type)
{
+ int r = 0;
+
spin_lock(&_lock);
- type->use_count = 0;
- list_add(&type->list, &_log_types);
+ if (!__find_dirty_log_type(type->name))
+ list_add(&type->list, &_log_types);
+ else
+ r = -EEXIST;
spin_unlock(&_lock);
- return 0;
+ return r;
}
EXPORT_SYMBOL(dm_dirty_log_type_register);
{
spin_lock(&_lock);
- if (type->use_count)
- DMWARN("Attempt to unregister a log type that is still in use");
- else
- list_del(&type->list);
+ if (!__find_dirty_log_type(type->name)) {
+ spin_unlock(&_lock);
+ return -EINVAL;
+ }
+
+ list_del(&type->list);
spin_unlock(&_lock);
EXPORT_SYMBOL(dm_dirty_log_type_unregister);
struct dm_dirty_log *dm_dirty_log_create(const char *type_name,
- struct dm_target *ti,
- unsigned int argc, char **argv)
+ struct dm_target *ti,
+ int (*flush_callback_fn)(struct dm_target *ti),
+ unsigned int argc, char **argv)
{
struct dm_dirty_log_type *type;
struct dm_dirty_log *log;
return NULL;
}
+ log->flush_callback_fn = flush_callback_fn;
log->type = type;
if (type->ctr(log, ti, argc, argv)) {
kfree(log);
struct log_c {
struct dm_target *ti;
- int touched;
+ int touched_dirtied;
+ int touched_cleaned;
+ int flush_failed;
uint32_t region_size;
unsigned int region_count;
region_t sync_count;
* Disk log fields
*/
int log_dev_failed;
+ int log_dev_flush_failed;
struct dm_dev *log_dev;
struct log_header header;
uint32_t *bs, unsigned bit)
{
ext2_set_bit(bit, (unsigned long *) bs);
- l->touched = 1;
+ l->touched_cleaned = 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;
+ l->touched_dirtied = 1;
}
/*----------------------------------------------------------------
static int rw_header(struct log_c *lc, int rw)
{
lc->io_req.bi_rw = rw;
- lc->io_req.mem.ptr.vma = lc->disk_header;
- lc->io_req.notify.fn = NULL;
return dm_io(&lc->io_req, 1, &lc->header_location, NULL);
}
+static int flush_header(struct log_c *lc)
+{
+ struct dm_io_region null_location = {
+ .bdev = lc->header_location.bdev,
+ .sector = 0,
+ .count = 0,
+ };
+
+ lc->io_req.bi_rw = WRITE_BARRIER;
+
+ return dm_io(&lc->io_req, 1, &null_location, NULL);
+}
+
static int read_header(struct log_c *log)
{
int r;
return 0;
}
-static inline int write_header(struct log_c *log)
+static int _check_region_size(struct dm_target *ti, uint32_t region_size)
{
- header_to_disk(&log->header, log->disk_header);
- return rw_header(log, WRITE);
+ if (region_size < 2 || region_size > ti->len)
+ return 0;
+
+ if (!is_power_of_2(region_size))
+ return 0;
+
+ return 1;
}
/*----------------------------------------------------------------
}
}
- if (sscanf(argv[0], "%u", ®ion_size) != 1) {
- DMWARN("invalid region size string");
+ if (sscanf(argv[0], "%u", ®ion_size) != 1 ||
+ !_check_region_size(ti, region_size)) {
+ DMWARN("invalid region size %s", argv[0]);
return -EINVAL;
}
}
lc->ti = ti;
- lc->touched = 0;
+ lc->touched_dirtied = 0;
+ lc->touched_cleaned = 0;
+ lc->flush_failed = 0;
lc->region_size = region_size;
lc->region_count = region_count;
lc->sync = sync;
} else {
lc->log_dev = dev;
lc->log_dev_failed = 0;
+ lc->log_dev_flush_failed = 0;
lc->header_location.bdev = lc->log_dev->bdev;
lc->header_location.sector = 0;
/*
* Buffer holds both header and bitset.
*/
- buf_size = dm_round_up((LOG_OFFSET << SECTOR_SHIFT) +
- bitset_size, ti->limits.hardsect_size);
+ buf_size =
+ dm_round_up((LOG_OFFSET << SECTOR_SHIFT) + bitset_size,
+ bdev_logical_block_size(lc->header_location.
+ bdev));
+
+ if (buf_size > i_size_read(dev->bdev->bd_inode)) {
+ DMWARN("log device %s too small: need %llu bytes",
+ dev->name, (unsigned long long)buf_size);
+ kfree(lc);
+ return -EINVAL;
+ }
+
lc->header_location.count = buf_size >> SECTOR_SHIFT;
+
lc->io_req.mem.type = DM_IO_VMA;
+ lc->io_req.notify.fn = NULL;
lc->io_req.client = dm_io_client_create(dm_div_up(buf_size,
PAGE_SIZE));
if (IS_ERR(lc->io_req.client)) {
lc->disk_header = vmalloc(buf_size);
if (!lc->disk_header) {
DMWARN("couldn't allocate disk log buffer");
+ dm_io_client_destroy(lc->io_req.client);
kfree(lc);
return -ENOMEM;
}
+ lc->io_req.mem.ptr.vma = lc->disk_header;
lc->clean_bits = (void *)lc->disk_header +
(LOG_OFFSET << SECTOR_SHIFT);
}
DMWARN("couldn't allocate sync bitset");
if (!dev)
vfree(lc->clean_bits);
+ else
+ dm_io_client_destroy(lc->io_req.client);
vfree(lc->disk_header);
kfree(lc);
return -ENOMEM;
vfree(lc->sync_bits);
if (!dev)
vfree(lc->clean_bits);
+ else
+ dm_io_client_destroy(lc->io_req.client);
vfree(lc->disk_header);
kfree(lc);
return -ENOMEM;
return -EINVAL;
}
- r = dm_get_device(ti, argv[0], 0, 0 /* FIXME */,
- FMODE_READ | FMODE_WRITE, &dev);
+ r = dm_get_device(ti, argv[0], FMODE_READ | FMODE_WRITE, &dev);
if (r)
return r;
/* set the correct number of regions in the header */
lc->header.nr_regions = lc->region_count;
+ header_to_disk(&lc->header, lc->disk_header);
+
/* write the new header */
- r = write_header(lc);
+ r = rw_header(lc, WRITE);
+ if (!r) {
+ r = flush_header(lc);
+ if (r)
+ lc->log_dev_flush_failed = 1;
+ }
if (r) {
DMWARN("%s: Failed to write header on dirty region log device",
lc->log_dev->name);
static int disk_flush(struct dm_dirty_log *log)
{
- int r;
- struct log_c *lc = (struct log_c *) log->context;
+ int r, i;
+ struct log_c *lc = log->context;
/* only write if the log has changed */
- if (!lc->touched)
+ if (!lc->touched_cleaned && !lc->touched_dirtied)
return 0;
- r = write_header(lc);
+ if (lc->touched_cleaned && log->flush_callback_fn &&
+ log->flush_callback_fn(lc->ti)) {
+ /*
+ * At this point it is impossible to determine which
+ * regions are clean and which are dirty (without
+ * re-reading the log off disk). So mark all of them
+ * dirty.
+ */
+ lc->flush_failed = 1;
+ for (i = 0; i < lc->region_count; i++)
+ log_clear_bit(lc, lc->clean_bits, i);
+ }
+
+ r = rw_header(lc, WRITE);
if (r)
fail_log_device(lc);
- else
- lc->touched = 0;
+ else {
+ if (lc->touched_dirtied) {
+ r = flush_header(lc);
+ if (r) {
+ lc->log_dev_flush_failed = 1;
+ fail_log_device(lc);
+ } else
+ lc->touched_dirtied = 0;
+ }
+ lc->touched_cleaned = 0;
+ }
return r;
}
static void core_clear_region(struct dm_dirty_log *log, region_t region)
{
struct log_c *lc = (struct log_c *) log->context;
- log_set_bit(lc, lc->clean_bits, region);
+ if (likely(!lc->flush_failed))
+ log_set_bit(lc, lc->clean_bits, region);
}
static int core_get_resync_work(struct dm_dirty_log *log, region_t *region)
switch(status) {
case STATUSTYPE_INFO:
DMEMIT("3 %s %s %c", log->type->name, lc->log_dev->name,
- lc->log_dev_failed ? 'D' : 'A');
+ lc->log_dev_flush_failed ? 'F' :
+ lc->log_dev_failed ? 'D' :
+ 'A');
break;
case STATUSTYPE_TABLE:
.status = disk_status,
};
-int __init dm_dirty_log_init(void)
+static int __init dm_dirty_log_init(void)
{
int r;
return r;
}
-void __exit dm_dirty_log_exit(void)
+static void __exit dm_dirty_log_exit(void)
{
dm_dirty_log_type_unregister(&_disk_type);
dm_dirty_log_type_unregister(&_core_type);
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff