1/*
  2 * Copyright (C) 2003 Sistina Software
  3 * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
  4 *
  5 * This file is released under the LGPL.
  6 */
  7
  8#include <linux/init.h>
  9#include <linux/slab.h>
 10#include <linux/module.h>
 11#include <linux/vmalloc.h>
 12#include <linux/dm-io.h>
 13#include <linux/dm-dirty-log.h>
 14
 15#include <linux/device-mapper.h>
 16
 17#define DM_MSG_PREFIX "dirty region log"
 18
 19static LIST_HEAD(_log_types);
 20static DEFINE_SPINLOCK(_lock);
 21
 22static struct dm_dirty_log_type *__find_dirty_log_type(const char *name)
 23{
 24	struct dm_dirty_log_type *log_type;
 25
 26	list_for_each_entry(log_type, &_log_types, list)
 27		if (!strcmp(name, log_type->name))
 28			return log_type;
 29
 30	return NULL;
 31}
 32
 33static struct dm_dirty_log_type *_get_dirty_log_type(const char *name)
 34{
 35	struct dm_dirty_log_type *log_type;
 36
 37	spin_lock(&_lock);
 38
 39	log_type = __find_dirty_log_type(name);
 40	if (log_type && !try_module_get(log_type->module))
 41		log_type = NULL;
 42
 43	spin_unlock(&_lock);
 44
 45	return log_type;
 46}
 47
 48/*
 49 * get_type
 50 * @type_name
 51 *
 52 * Attempt to retrieve the dm_dirty_log_type by name.  If not already
 53 * available, attempt to load the appropriate module.
 54 *
 55 * Log modules are named "dm-log-" followed by the 'type_name'.
 56 * Modules may contain multiple types.
 57 * This function will first try the module "dm-log-<type_name>",
 58 * then truncate 'type_name' on the last '-' and try again.
 59 *
 60 * For example, if type_name was "clustered-disk", it would search
 61 * 'dm-log-clustered-disk' then 'dm-log-clustered'.
 62 *
 63 * Returns: dirty_log_type* on success, NULL on failure
 64 */
 65static struct dm_dirty_log_type *get_type(const char *type_name)
 66{
 67	char *p, *type_name_dup;
 68	struct dm_dirty_log_type *log_type;
 69
 70	if (!type_name)
 71		return NULL;
 72
 73	log_type = _get_dirty_log_type(type_name);
 74	if (log_type)
 75		return log_type;
 76
 77	type_name_dup = kstrdup(type_name, GFP_KERNEL);
 78	if (!type_name_dup) {
 79		DMWARN("No memory left to attempt log module load for \"%s\"",
 80		       type_name);
 81		return NULL;
 82	}
 83
 84	while (request_module("dm-log-%s", type_name_dup) ||
 85	       !(log_type = _get_dirty_log_type(type_name))) {
 86		p = strrchr(type_name_dup, '-');
 87		if (!p)
 88			break;
 89		p[0] = '\0';
 90	}
 91
 92	if (!log_type)
 93		DMWARN("Module for logging type \"%s\" not found.", type_name);
 94
 95	kfree(type_name_dup);
 96
 97	return log_type;
 98}
 99
100static void put_type(struct dm_dirty_log_type *type)
101{
102	if (!type)
103		return;
104
105	spin_lock(&_lock);
106	if (!__find_dirty_log_type(type->name))
107		goto out;
108
109	module_put(type->module);
110
111out:
112	spin_unlock(&_lock);
113}
114
115int dm_dirty_log_type_register(struct dm_dirty_log_type *type)
116{
117	int r = 0;
118
119	spin_lock(&_lock);
120	if (!__find_dirty_log_type(type->name))
121		list_add(&type->list, &_log_types);
122	else
123		r = -EEXIST;
124	spin_unlock(&_lock);
125
126	return r;
127}
128EXPORT_SYMBOL(dm_dirty_log_type_register);
129
130int dm_dirty_log_type_unregister(struct dm_dirty_log_type *type)
131{
132	spin_lock(&_lock);
133
134	if (!__find_dirty_log_type(type->name)) {
135		spin_unlock(&_lock);
136		return -EINVAL;
137	}
138
139	list_del(&type->list);
140
141	spin_unlock(&_lock);
142
143	return 0;
144}
145EXPORT_SYMBOL(dm_dirty_log_type_unregister);
146
147struct dm_dirty_log *dm_dirty_log_create(const char *type_name,
148			struct dm_target *ti,
149			int (*flush_callback_fn)(struct dm_target *ti),
150			unsigned int argc, char **argv)
151{
152	struct dm_dirty_log_type *type;
153	struct dm_dirty_log *log;
154
155	log = kmalloc(sizeof(*log), GFP_KERNEL);
156	if (!log)
157		return NULL;
158
159	type = get_type(type_name);
160	if (!type) {
161		kfree(log);
162		return NULL;
163	}
164
165	log->flush_callback_fn = flush_callback_fn;
166	log->type = type;
167	if (type->ctr(log, ti, argc, argv)) {
168		kfree(log);
169		put_type(type);
170		return NULL;
171	}
172
173	return log;
174}
175EXPORT_SYMBOL(dm_dirty_log_create);
176
177void dm_dirty_log_destroy(struct dm_dirty_log *log)
178{
179	log->type->dtr(log);
180	put_type(log->type);
181	kfree(log);
182}
183EXPORT_SYMBOL(dm_dirty_log_destroy);
184
185/*-----------------------------------------------------------------
186 * Persistent and core logs share a lot of their implementation.
187 * FIXME: need a reload method to be called from a resume
188 *---------------------------------------------------------------*/
189/*
190 * Magic for persistent mirrors: "MiRr"
191 */
192#define MIRROR_MAGIC 0x4D695272
193
194/*
195 * The on-disk version of the metadata.
196 */
197#define MIRROR_DISK_VERSION 2
198#define LOG_OFFSET 2
199
200struct log_header_disk {
201	__le32 magic;
202
203	/*
204	 * Simple, incrementing version. no backward
205	 * compatibility.
206	 */
207	__le32 version;
208	__le64 nr_regions;
209} __packed;
210
211struct log_header_core {
212	uint32_t magic;
213	uint32_t version;
214	uint64_t nr_regions;
215};
216
217struct log_c {
218	struct dm_target *ti;
219	int touched_dirtied;
220	int touched_cleaned;
221	int flush_failed;
222	uint32_t region_size;
223	unsigned int region_count;
224	region_t sync_count;
225
226	unsigned bitset_uint32_count;
227	uint32_t *clean_bits;
228	uint32_t *sync_bits;
229	uint32_t *recovering_bits;	/* FIXME: this seems excessive */
230
231	int sync_search;
232
233	/* Resync flag */
234	enum sync {
235		DEFAULTSYNC,	/* Synchronize if necessary */
236		NOSYNC,		/* Devices known to be already in sync */
237		FORCESYNC,	/* Force a sync to happen */
238	} sync;
239
240	struct dm_io_request io_req;
241
242	/*
243	 * Disk log fields
244	 */
245	int log_dev_failed;
246	int log_dev_flush_failed;
247	struct dm_dev *log_dev;
248	struct log_header_core header;
249
250	struct dm_io_region header_location;
251	struct log_header_disk *disk_header;
252};
253
254/*
255 * The touched member needs to be updated every time we access
256 * one of the bitsets.
257 */
258static inline int log_test_bit(uint32_t *bs, unsigned bit)
259{
260	return test_bit_le(bit, bs) ? 1 : 0;
261}
262
263static inline void log_set_bit(struct log_c *l,
264			       uint32_t *bs, unsigned bit)
265{
266	__set_bit_le(bit, bs);
267	l->touched_cleaned = 1;
268}
269
270static inline void log_clear_bit(struct log_c *l,
271				 uint32_t *bs, unsigned bit)
272{
273	__clear_bit_le(bit, bs);
274	l->touched_dirtied = 1;
275}
276
277/*----------------------------------------------------------------
278 * Header IO
279 *--------------------------------------------------------------*/
280static void header_to_disk(struct log_header_core *core, struct log_header_disk *disk)
281{
282	disk->magic = cpu_to_le32(core->magic);
283	disk->version = cpu_to_le32(core->version);
284	disk->nr_regions = cpu_to_le64(core->nr_regions);
285}
286
287static void header_from_disk(struct log_header_core *core, struct log_header_disk *disk)
288{
289	core->magic = le32_to_cpu(disk->magic);
290	core->version = le32_to_cpu(disk->version);
291	core->nr_regions = le64_to_cpu(disk->nr_regions);
292}
293
294static int rw_header(struct log_c *lc, int rw)
295{
296	lc->io_req.bi_rw = rw;
297
298	return dm_io(&lc->io_req, 1, &lc->header_location, NULL);
299}
300
301static int flush_header(struct log_c *lc)
302{
303	struct dm_io_region null_location = {
304		.bdev = lc->header_location.bdev,
305		.sector = 0,
306		.count = 0,
307	};
308
309	lc->io_req.bi_rw = WRITE_FLUSH;
310
311	return dm_io(&lc->io_req, 1, &null_location, NULL);
312}
313
314static int read_header(struct log_c *log)
315{
316	int r;
317
318	r = rw_header(log, READ);
319	if (r)
320		return r;
321
322	header_from_disk(&log->header, log->disk_header);
323
324	/* New log required? */
325	if (log->sync != DEFAULTSYNC || log->header.magic != MIRROR_MAGIC) {
326		log->header.magic = MIRROR_MAGIC;
327		log->header.version = MIRROR_DISK_VERSION;
328		log->header.nr_regions = 0;
329	}
330
331#ifdef __LITTLE_ENDIAN
332	if (log->header.version == 1)
333		log->header.version = 2;
334#endif
335
336	if (log->header.version != MIRROR_DISK_VERSION) {
337		DMWARN("incompatible disk log version");
338		return -EINVAL;
339	}
340
341	return 0;
342}
343
344static int _check_region_size(struct dm_target *ti, uint32_t region_size)
345{
346	if (region_size < 2 || region_size > ti->len)
347		return 0;
348
349	if (!is_power_of_2(region_size))
350		return 0;
351
352	return 1;
353}
354
355/*----------------------------------------------------------------
356 * core log constructor/destructor
357 *
358 * argv contains region_size followed optionally by [no]sync
359 *--------------------------------------------------------------*/
360#define BYTE_SHIFT 3
361static int create_log_context(struct dm_dirty_log *log, struct dm_target *ti,
362			      unsigned int argc, char **argv,
363			      struct dm_dev *dev)
364{
365	enum sync sync = DEFAULTSYNC;
366
367	struct log_c *lc;
368	uint32_t region_size;
369	unsigned int region_count;
370	size_t bitset_size, buf_size;
371	int r;
 
372
373	if (argc < 1 || argc > 2) {
374		DMWARN("wrong number of arguments to dirty region log");
375		return -EINVAL;
376	}
377
378	if (argc > 1) {
379		if (!strcmp(argv[1], "sync"))
380			sync = FORCESYNC;
381		else if (!strcmp(argv[1], "nosync"))
382			sync = NOSYNC;
383		else {
384			DMWARN("unrecognised sync argument to "
385			       "dirty region log: %s", argv[1]);
386			return -EINVAL;
387		}
388	}
389
390	if (sscanf(argv[0], "%u", &region_size) != 1 ||
391	    !_check_region_size(ti, region_size)) {
392		DMWARN("invalid region size %s", argv[0]);
393		return -EINVAL;
394	}
395
396	region_count = dm_sector_div_up(ti->len, region_size);
397
398	lc = kmalloc(sizeof(*lc), GFP_KERNEL);
399	if (!lc) {
400		DMWARN("couldn't allocate core log");
401		return -ENOMEM;
402	}
403
404	lc->ti = ti;
405	lc->touched_dirtied = 0;
406	lc->touched_cleaned = 0;
407	lc->flush_failed = 0;
408	lc->region_size = region_size;
409	lc->region_count = region_count;
410	lc->sync = sync;
411
412	/*
413	 * Work out how many "unsigned long"s we need to hold the bitset.
414	 */
415	bitset_size = dm_round_up(region_count,
416				  sizeof(*lc->clean_bits) << BYTE_SHIFT);
417	bitset_size >>= BYTE_SHIFT;
418
419	lc->bitset_uint32_count = bitset_size / sizeof(*lc->clean_bits);
420
421	/*
422	 * Disk log?
423	 */
424	if (!dev) {
425		lc->clean_bits = vmalloc(bitset_size);
426		if (!lc->clean_bits) {
427			DMWARN("couldn't allocate clean bitset");
428			kfree(lc);
429			return -ENOMEM;
430		}
431		lc->disk_header = NULL;
432	} else {
433		lc->log_dev = dev;
434		lc->log_dev_failed = 0;
435		lc->log_dev_flush_failed = 0;
436		lc->header_location.bdev = lc->log_dev->bdev;
437		lc->header_location.sector = 0;
438
439		/*
440		 * Buffer holds both header and bitset.
441		 */
442		buf_size =
443		    dm_round_up((LOG_OFFSET << SECTOR_SHIFT) + bitset_size,
444				bdev_logical_block_size(lc->header_location.
445							    bdev));
446
447		if (buf_size > i_size_read(dev->bdev->bd_inode)) {
448			DMWARN("log device %s too small: need %llu bytes",
449				dev->name, (unsigned long long)buf_size);
450			kfree(lc);
451			return -EINVAL;
452		}
453
454		lc->header_location.count = buf_size >> SECTOR_SHIFT;
455
456		lc->io_req.mem.type = DM_IO_VMA;
457		lc->io_req.notify.fn = NULL;
458		lc->io_req.client = dm_io_client_create();
459		if (IS_ERR(lc->io_req.client)) {
460			r = PTR_ERR(lc->io_req.client);
461			DMWARN("couldn't allocate disk io client");
462			kfree(lc);
463			return r;
464		}
465
466		lc->disk_header = vmalloc(buf_size);
467		if (!lc->disk_header) {
468			DMWARN("couldn't allocate disk log buffer");
469			dm_io_client_destroy(lc->io_req.client);
470			kfree(lc);
471			return -ENOMEM;
472		}
473
474		lc->io_req.mem.ptr.vma = lc->disk_header;
475		lc->clean_bits = (void *)lc->disk_header +
476				 (LOG_OFFSET << SECTOR_SHIFT);
477	}
478
479	memset(lc->clean_bits, -1, bitset_size);
480
481	lc->sync_bits = vmalloc(bitset_size);
482	if (!lc->sync_bits) {
483		DMWARN("couldn't allocate sync bitset");
484		if (!dev)
485			vfree(lc->clean_bits);
486		else
487			dm_io_client_destroy(lc->io_req.client);
488		vfree(lc->disk_header);
489		kfree(lc);
490		return -ENOMEM;
491	}
492	memset(lc->sync_bits, (sync == NOSYNC) ? -1 : 0, bitset_size);
493	lc->sync_count = (sync == NOSYNC) ? region_count : 0;
494
495	lc->recovering_bits = vzalloc(bitset_size);
496	if (!lc->recovering_bits) {
497		DMWARN("couldn't allocate sync bitset");
498		vfree(lc->sync_bits);
499		if (!dev)
500			vfree(lc->clean_bits);
501		else
502			dm_io_client_destroy(lc->io_req.client);
503		vfree(lc->disk_header);
504		kfree(lc);
505		return -ENOMEM;
506	}
507	lc->sync_search = 0;
508	log->context = lc;
509
510	return 0;
511}
512
513static int core_ctr(struct dm_dirty_log *log, struct dm_target *ti,
514		    unsigned int argc, char **argv)
515{
516	return create_log_context(log, ti, argc, argv, NULL);
517}
518
519static void destroy_log_context(struct log_c *lc)
520{
521	vfree(lc->sync_bits);
522	vfree(lc->recovering_bits);
523	kfree(lc);
524}
525
526static void core_dtr(struct dm_dirty_log *log)
527{
528	struct log_c *lc = (struct log_c *) log->context;
529
530	vfree(lc->clean_bits);
531	destroy_log_context(lc);
532}
533
534/*----------------------------------------------------------------
535 * disk log constructor/destructor
536 *
537 * argv contains log_device region_size followed optionally by [no]sync
538 *--------------------------------------------------------------*/
539static int disk_ctr(struct dm_dirty_log *log, struct dm_target *ti,
540		    unsigned int argc, char **argv)
541{
542	int r;
543	struct dm_dev *dev;
544
545	if (argc < 2 || argc > 3) {
546		DMWARN("wrong number of arguments to disk dirty region log");
547		return -EINVAL;
548	}
549
550	r = dm_get_device(ti, argv[0], dm_table_get_mode(ti->table), &dev);
551	if (r)
552		return r;
553
554	r = create_log_context(log, ti, argc - 1, argv + 1, dev);
555	if (r) {
556		dm_put_device(ti, dev);
557		return r;
558	}
559
560	return 0;
561}
562
563static void disk_dtr(struct dm_dirty_log *log)
564{
565	struct log_c *lc = (struct log_c *) log->context;
566
567	dm_put_device(lc->ti, lc->log_dev);
568	vfree(lc->disk_header);
569	dm_io_client_destroy(lc->io_req.client);
570	destroy_log_context(lc);
571}
572
573static int count_bits32(uint32_t *addr, unsigned size)
574{
575	int count = 0, i;
576
577	for (i = 0; i < size; i++) {
578		count += hweight32(*(addr+i));
579	}
580	return count;
581}
582
583static void fail_log_device(struct log_c *lc)
584{
585	if (lc->log_dev_failed)
586		return;
587
588	lc->log_dev_failed = 1;
589	dm_table_event(lc->ti->table);
590}
591
592static int disk_resume(struct dm_dirty_log *log)
593{
594	int r;
595	unsigned i;
596	struct log_c *lc = (struct log_c *) log->context;
597	size_t size = lc->bitset_uint32_count * sizeof(uint32_t);
598
599	/* read the disk header */
600	r = read_header(lc);
601	if (r) {
602		DMWARN("%s: Failed to read header on dirty region log device",
603		       lc->log_dev->name);
604		fail_log_device(lc);
605		/*
606		 * If the log device cannot be read, we must assume
607		 * all regions are out-of-sync.  If we simply return
608		 * here, the state will be uninitialized and could
609		 * lead us to return 'in-sync' status for regions
610		 * that are actually 'out-of-sync'.
611		 */
612		lc->header.nr_regions = 0;
613	}
614
615	/* set or clear any new bits -- device has grown */
616	if (lc->sync == NOSYNC)
617		for (i = lc->header.nr_regions; i < lc->region_count; i++)
618			/* FIXME: amazingly inefficient */
619			log_set_bit(lc, lc->clean_bits, i);
620	else
621		for (i = lc->header.nr_regions; i < lc->region_count; i++)
622			/* FIXME: amazingly inefficient */
623			log_clear_bit(lc, lc->clean_bits, i);
624
625	/* clear any old bits -- device has shrunk */
626	for (i = lc->region_count; i % (sizeof(*lc->clean_bits) << BYTE_SHIFT); i++)
627		log_clear_bit(lc, lc->clean_bits, i);
628
629	/* copy clean across to sync */
630	memcpy(lc->sync_bits, lc->clean_bits, size);
631	lc->sync_count = count_bits32(lc->clean_bits, lc->bitset_uint32_count);
 
632	lc->sync_search = 0;
633
634	/* set the correct number of regions in the header */
635	lc->header.nr_regions = lc->region_count;
636
637	header_to_disk(&lc->header, lc->disk_header);
638
639	/* write the new header */
640	r = rw_header(lc, WRITE);
641	if (!r) {
642		r = flush_header(lc);
643		if (r)
644			lc->log_dev_flush_failed = 1;
645	}
646	if (r) {
647		DMWARN("%s: Failed to write header on dirty region log device",
648		       lc->log_dev->name);
649		fail_log_device(lc);
650	}
651
652	return r;
653}
654
655static uint32_t core_get_region_size(struct dm_dirty_log *log)
656{
657	struct log_c *lc = (struct log_c *) log->context;
658	return lc->region_size;
659}
660
661static int core_resume(struct dm_dirty_log *log)
662{
663	struct log_c *lc = (struct log_c *) log->context;
664	lc->sync_search = 0;
665	return 0;
666}
667
668static int core_is_clean(struct dm_dirty_log *log, region_t region)
669{
670	struct log_c *lc = (struct log_c *) log->context;
671	return log_test_bit(lc->clean_bits, region);
672}
673
674static int core_in_sync(struct dm_dirty_log *log, region_t region, int block)
675{
676	struct log_c *lc = (struct log_c *) log->context;
677	return log_test_bit(lc->sync_bits, region);
678}
679
680static int core_flush(struct dm_dirty_log *log)
681{
682	/* no op */
683	return 0;
684}
685
686static int disk_flush(struct dm_dirty_log *log)
687{
688	int r, i;
689	struct log_c *lc = log->context;
690
691	/* only write if the log has changed */
692	if (!lc->touched_cleaned && !lc->touched_dirtied)
693		return 0;
694
695	if (lc->touched_cleaned && log->flush_callback_fn &&
696	    log->flush_callback_fn(lc->ti)) {
697		/*
698		 * At this point it is impossible to determine which
699		 * regions are clean and which are dirty (without
700		 * re-reading the log off disk). So mark all of them
701		 * dirty.
702		 */
703		lc->flush_failed = 1;
704		for (i = 0; i < lc->region_count; i++)
705			log_clear_bit(lc, lc->clean_bits, i);
706	}
707
708	r = rw_header(lc, WRITE);
709	if (r)
710		fail_log_device(lc);
711	else {
712		if (lc->touched_dirtied) {
713			r = flush_header(lc);
714			if (r) {
715				lc->log_dev_flush_failed = 1;
716				fail_log_device(lc);
717			} else
718				lc->touched_dirtied = 0;
719		}
720		lc->touched_cleaned = 0;
721	}
722
723	return r;
724}
725
726static void core_mark_region(struct dm_dirty_log *log, region_t region)
727{
728	struct log_c *lc = (struct log_c *) log->context;
729	log_clear_bit(lc, lc->clean_bits, region);
730}
731
732static void core_clear_region(struct dm_dirty_log *log, region_t region)
733{
734	struct log_c *lc = (struct log_c *) log->context;
735	if (likely(!lc->flush_failed))
736		log_set_bit(lc, lc->clean_bits, region);
737}
738
739static int core_get_resync_work(struct dm_dirty_log *log, region_t *region)
740{
741	struct log_c *lc = (struct log_c *) log->context;
742
743	if (lc->sync_search >= lc->region_count)
744		return 0;
745
746	do {
747		*region = find_next_zero_bit_le(lc->sync_bits,
748					     lc->region_count,
749					     lc->sync_search);
750		lc->sync_search = *region + 1;
751
752		if (*region >= lc->region_count)
753			return 0;
754
755	} while (log_test_bit(lc->recovering_bits, *region));
756
757	log_set_bit(lc, lc->recovering_bits, *region);
758	return 1;
759}
760
761static void core_set_region_sync(struct dm_dirty_log *log, region_t region,
762				 int in_sync)
763{
764	struct log_c *lc = (struct log_c *) log->context;
765
766	log_clear_bit(lc, lc->recovering_bits, region);
767	if (in_sync) {
768		log_set_bit(lc, lc->sync_bits, region);
769                lc->sync_count++;
770        } else if (log_test_bit(lc->sync_bits, region)) {
771		lc->sync_count--;
772		log_clear_bit(lc, lc->sync_bits, region);
773	}
774}
775
776static region_t core_get_sync_count(struct dm_dirty_log *log)
777{
778        struct log_c *lc = (struct log_c *) log->context;
779
780        return lc->sync_count;
781}
782
783#define	DMEMIT_SYNC \
784	if (lc->sync != DEFAULTSYNC) \
785		DMEMIT("%ssync ", lc->sync == NOSYNC ? "no" : "")
786
787static int core_status(struct dm_dirty_log *log, status_type_t status,
788		       char *result, unsigned int maxlen)
789{
790	int sz = 0;
791	struct log_c *lc = log->context;
792
793	switch(status) {
794	case STATUSTYPE_INFO:
795		DMEMIT("1 %s", log->type->name);
796		break;
797
798	case STATUSTYPE_TABLE:
799		DMEMIT("%s %u %u ", log->type->name,
800		       lc->sync == DEFAULTSYNC ? 1 : 2, lc->region_size);
801		DMEMIT_SYNC;
 
 
 
 
 
802	}
803
804	return sz;
805}
806
807static int disk_status(struct dm_dirty_log *log, status_type_t status,
808		       char *result, unsigned int maxlen)
809{
810	int sz = 0;
811	struct log_c *lc = log->context;
812
813	switch(status) {
814	case STATUSTYPE_INFO:
815		DMEMIT("3 %s %s %c", log->type->name, lc->log_dev->name,
816		       lc->log_dev_flush_failed ? 'F' :
817		       lc->log_dev_failed ? 'D' :
818		       'A');
819		break;
820
821	case STATUSTYPE_TABLE:
822		DMEMIT("%s %u %s %u ", log->type->name,
823		       lc->sync == DEFAULTSYNC ? 2 : 3, lc->log_dev->name,
824		       lc->region_size);
825		DMEMIT_SYNC;
 
 
 
 
 
826	}
827
828	return sz;
829}
830
831static struct dm_dirty_log_type _core_type = {
832	.name = "core",
833	.module = THIS_MODULE,
834	.ctr = core_ctr,
835	.dtr = core_dtr,
836	.resume = core_resume,
837	.get_region_size = core_get_region_size,
838	.is_clean = core_is_clean,
839	.in_sync = core_in_sync,
840	.flush = core_flush,
841	.mark_region = core_mark_region,
842	.clear_region = core_clear_region,
843	.get_resync_work = core_get_resync_work,
844	.set_region_sync = core_set_region_sync,
845	.get_sync_count = core_get_sync_count,
846	.status = core_status,
847};
848
849static struct dm_dirty_log_type _disk_type = {
850	.name = "disk",
851	.module = THIS_MODULE,
852	.ctr = disk_ctr,
853	.dtr = disk_dtr,
854	.postsuspend = disk_flush,
855	.resume = disk_resume,
856	.get_region_size = core_get_region_size,
857	.is_clean = core_is_clean,
858	.in_sync = core_in_sync,
859	.flush = disk_flush,
860	.mark_region = core_mark_region,
861	.clear_region = core_clear_region,
862	.get_resync_work = core_get_resync_work,
863	.set_region_sync = core_set_region_sync,
864	.get_sync_count = core_get_sync_count,
865	.status = disk_status,
866};
867
868static int __init dm_dirty_log_init(void)
869{
870	int r;
871
872	r = dm_dirty_log_type_register(&_core_type);
873	if (r)
874		DMWARN("couldn't register core log");
875
876	r = dm_dirty_log_type_register(&_disk_type);
877	if (r) {
878		DMWARN("couldn't register disk type");
879		dm_dirty_log_type_unregister(&_core_type);
880	}
881
882	return r;
883}
884
885static void __exit dm_dirty_log_exit(void)
886{
887	dm_dirty_log_type_unregister(&_disk_type);
888	dm_dirty_log_type_unregister(&_core_type);
889}
890
891module_init(dm_dirty_log_init);
892module_exit(dm_dirty_log_exit);
893
894MODULE_DESCRIPTION(DM_NAME " dirty region log");
895MODULE_AUTHOR("Joe Thornber, Heinz Mauelshagen <dm-devel@redhat.com>");
896MODULE_LICENSE("GPL");