#define DM_MSG_PREFIX "dirty region log"
-struct dm_dirty_log_internal {
- struct dm_dirty_log_type *type;
-
- struct list_head list;
- long use;
-};
-
static LIST_HEAD(_log_types);
static DEFINE_SPINLOCK(_lock);
-static struct dm_dirty_log_internal *__find_dirty_log_type(const char *name)
+static struct dm_dirty_log_type *__find_dirty_log_type(const char *name)
{
- struct dm_dirty_log_internal *log_type;
+ struct dm_dirty_log_type *log_type;
list_for_each_entry(log_type, &_log_types, list)
- if (!strcmp(name, log_type->type->name))
+ if (!strcmp(name, log_type->name))
return log_type;
return NULL;
}
-static struct dm_dirty_log_internal *_get_dirty_log_type(const char *name)
+static struct dm_dirty_log_type *_get_dirty_log_type(const char *name)
{
- struct dm_dirty_log_internal *log_type;
+ struct dm_dirty_log_type *log_type;
spin_lock(&_lock);
log_type = __find_dirty_log_type(name);
- if (log_type) {
- if (!log_type->use && !try_module_get(log_type->type->module))
- log_type = NULL;
- else
- log_type->use++;
- }
+ if (log_type && !try_module_get(log_type->module))
+ log_type = NULL;
spin_unlock(&_lock);
static struct dm_dirty_log_type *get_type(const char *type_name)
{
char *p, *type_name_dup;
- struct dm_dirty_log_internal *log_type;
+ struct dm_dirty_log_type *log_type;
if (!type_name)
return NULL;
log_type = _get_dirty_log_type(type_name);
if (log_type)
- return log_type->type;
+ return log_type;
type_name_dup = kstrdup(type_name, GFP_KERNEL);
if (!type_name_dup) {
kfree(type_name_dup);
- return log_type ? log_type->type : NULL;
+ return log_type;
}
static void put_type(struct dm_dirty_log_type *type)
{
- struct dm_dirty_log_internal *log_type;
-
if (!type)
return;
spin_lock(&_lock);
- log_type = __find_dirty_log_type(type->name);
- if (!log_type)
+ if (!__find_dirty_log_type(type->name))
goto out;
- if (!--log_type->use)
- module_put(type->module);
-
- BUG_ON(log_type->use < 0);
+ module_put(type->module);
out:
spin_unlock(&_lock);
}
-static struct dm_dirty_log_internal *_alloc_dirty_log_type(struct dm_dirty_log_type *type)
-{
- struct dm_dirty_log_internal *log_type = kzalloc(sizeof(*log_type),
- GFP_KERNEL);
-
- if (log_type)
- log_type->type = type;
-
- return log_type;
-}
-
int dm_dirty_log_type_register(struct dm_dirty_log_type *type)
{
- struct dm_dirty_log_internal *log_type = _alloc_dirty_log_type(type);
int r = 0;
- if (!log_type)
- return -ENOMEM;
-
spin_lock(&_lock);
if (!__find_dirty_log_type(type->name))
- list_add(&log_type->list, &_log_types);
- else {
- kfree(log_type);
+ list_add(&type->list, &_log_types);
+ else
r = -EEXIST;
- }
spin_unlock(&_lock);
return r;
int dm_dirty_log_type_unregister(struct dm_dirty_log_type *type)
{
- struct dm_dirty_log_internal *log_type;
-
spin_lock(&_lock);
- log_type = __find_dirty_log_type(type->name);
- if (!log_type) {
+ if (!__find_dirty_log_type(type->name)) {
spin_unlock(&_lock);
return -EINVAL;
}
- if (log_type->use) {
- spin_unlock(&_lock);
- return -ETXTBSY;
- }
-
- list_del(&log_type->list);
+ list_del(&type->list);
spin_unlock(&_lock);
- kfree(log_type);
return 0;
}
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;
}
/*----------------------------------------------------------------
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;
}
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;
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;
/* write the new header */
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;
+ 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:
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