1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2003 Sistina Software
4 * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved.
5 *
6 * This file is released under the LGPL.
7 */
8
9#include <linux/init.h>
10#include <linux/slab.h>
11#include <linux/module.h>
12#include <linux/vmalloc.h>
13#include <linux/dm-io.h>
14#include <linux/dm-dirty-log.h>
15
16#include <linux/device-mapper.h>
17
18#define DM_MSG_PREFIX "dirty region log"
19
20static LIST_HEAD(_log_types);
21static DEFINE_SPINLOCK(_lock);
22
23static struct dm_dirty_log_type *__find_dirty_log_type(const char *name)
24{
25	struct dm_dirty_log_type *log_type;
26
27	list_for_each_entry(log_type, &_log_types, list)
28		if (!strcmp(name, log_type->name))
29			return log_type;
30
31	return NULL;
32}
33
34static struct dm_dirty_log_type *_get_dirty_log_type(const char *name)
35{
36	struct dm_dirty_log_type *log_type;
37
38	spin_lock(&_lock);
39
40	log_type = __find_dirty_log_type(name);
41	if (log_type && !try_module_get(log_type->module))
42		log_type = NULL;
43
44	spin_unlock(&_lock);
45
46	return log_type;
47}
48
49/*
50 * get_type
51 * @type_name
52 *
53 * Attempt to retrieve the dm_dirty_log_type by name.  If not already
54 * available, attempt to load the appropriate module.
55 *
56 * Log modules are named "dm-log-" followed by the 'type_name'.
57 * Modules may contain multiple types.
58 * This function will first try the module "dm-log-<type_name>",
59 * then truncate 'type_name' on the last '-' and try again.
60 *
61 * For example, if type_name was "clustered-disk", it would search
62 * 'dm-log-clustered-disk' then 'dm-log-clustered'.
63 *
64 * Returns: dirty_log_type* on success, NULL on failure
65 */
66static struct dm_dirty_log_type *get_type(const char *type_name)
67{
68	char *p, *type_name_dup;
69	struct dm_dirty_log_type *log_type;
70
71	if (!type_name)
72		return NULL;
73
74	log_type = _get_dirty_log_type(type_name);
75	if (log_type)
76		return log_type;
77
78	type_name_dup = kstrdup(type_name, GFP_KERNEL);
79	if (!type_name_dup) {
80		DMWARN("No memory left to attempt log module load for \"%s\"",
81		       type_name);
82		return NULL;
83	}
84
85	while (request_module("dm-log-%s", type_name_dup) ||
86	       !(log_type = _get_dirty_log_type(type_name))) {
87		p = strrchr(type_name_dup, '-');
88		if (!p)
89			break;
90		p[0] = '\0';
91	}
92
93	if (!log_type)
94		DMWARN("Module for logging type \"%s\" not found.", type_name);
95
96	kfree(type_name_dup);
97
98	return log_type;
99}
100
101static void put_type(struct dm_dirty_log_type *type)
102{
103	if (!type)
104		return;
105
106	spin_lock(&_lock);
107	if (!__find_dirty_log_type(type->name))
108		goto out;
109
110	module_put(type->module);
111
112out:
113	spin_unlock(&_lock);
114}
115
116int dm_dirty_log_type_register(struct dm_dirty_log_type *type)
117{
118	int r = 0;
119
120	spin_lock(&_lock);
121	if (!__find_dirty_log_type(type->name))
122		list_add(&type->list, &_log_types);
123	else
124		r = -EEXIST;
125	spin_unlock(&_lock);
126
127	return r;
128}
129EXPORT_SYMBOL(dm_dirty_log_type_register);
130
131int dm_dirty_log_type_unregister(struct dm_dirty_log_type *type)
132{
133	spin_lock(&_lock);
134
135	if (!__find_dirty_log_type(type->name)) {
136		spin_unlock(&_lock);
137		return -EINVAL;
138	}
139
140	list_del(&type->list);
141
142	spin_unlock(&_lock);
143
144	return 0;
145}
146EXPORT_SYMBOL(dm_dirty_log_type_unregister);
147
148struct dm_dirty_log *dm_dirty_log_create(const char *type_name,
149			struct dm_target *ti,
150			int (*flush_callback_fn)(struct dm_target *ti),
151			unsigned int argc, char **argv)
152{
153	struct dm_dirty_log_type *type;
154	struct dm_dirty_log *log;
155
156	log = kmalloc(sizeof(*log), GFP_KERNEL);
157	if (!log)
158		return NULL;
159
160	type = get_type(type_name);
161	if (!type) {
162		kfree(log);
163		return NULL;
164	}
165
166	log->flush_callback_fn = flush_callback_fn;
167	log->type = type;
168	if (type->ctr(log, ti, argc, argv)) {
169		kfree(log);
170		put_type(type);
171		return NULL;
172	}
173
174	return log;
175}
176EXPORT_SYMBOL(dm_dirty_log_create);
177
178void dm_dirty_log_destroy(struct dm_dirty_log *log)
179{
180	log->type->dtr(log);
181	put_type(log->type);
182	kfree(log);
183}
184EXPORT_SYMBOL(dm_dirty_log_destroy);
185
186/*
187 *---------------------------------------------------------------
188 * Persistent and core logs share a lot of their implementation.
189 * FIXME: need a reload method to be called from a resume
190 *---------------------------------------------------------------
191 */
192/*
193 * Magic for persistent mirrors: "MiRr"
194 */
195#define MIRROR_MAGIC 0x4D695272
196
197/*
198 * The on-disk version of the metadata.
199 */
200#define MIRROR_DISK_VERSION 2
201#define LOG_OFFSET 2
202
203struct log_header_disk {
204	__le32 magic;
205
206	/*
207	 * Simple, incrementing version. no backward
208	 * compatibility.
209	 */
210	__le32 version;
211	__le64 nr_regions;
212} __packed;
213
214struct log_header_core {
215	uint32_t magic;
216	uint32_t version;
217	uint64_t nr_regions;
218};
219
220struct log_c {
221	struct dm_target *ti;
222	int touched_dirtied;
223	int touched_cleaned;
224	int flush_failed;
225	uint32_t region_size;
226	unsigned int region_count;
227	region_t sync_count;
228
229	unsigned int bitset_uint32_count;
230	uint32_t *clean_bits;
231	uint32_t *sync_bits;
232	uint32_t *recovering_bits;	/* FIXME: this seems excessive */
233
234	int sync_search;
235
236	/* Resync flag */
237	enum sync {
238		DEFAULTSYNC,	/* Synchronize if necessary */
239		NOSYNC,		/* Devices known to be already in sync */
240		FORCESYNC,	/* Force a sync to happen */
241	} sync;
242
243	struct dm_io_request io_req;
244
245	/*
246	 * Disk log fields
247	 */
248	int log_dev_failed;
249	int log_dev_flush_failed;
250	struct dm_dev *log_dev;
251	struct log_header_core header;
252
253	struct dm_io_region header_location;
254	struct log_header_disk *disk_header;
255};
256
257/*
258 * The touched member needs to be updated every time we access
259 * one of the bitsets.
260 */
261static inline int log_test_bit(uint32_t *bs, unsigned int bit)
262{
263	return test_bit_le(bit, bs) ? 1 : 0;
264}
265
266static inline void log_set_bit(struct log_c *l,
267			       uint32_t *bs, unsigned int bit)
268{
269	__set_bit_le(bit, bs);
270	l->touched_cleaned = 1;
271}
272
273static inline void log_clear_bit(struct log_c *l,
274				 uint32_t *bs, unsigned int bit)
275{
276	__clear_bit_le(bit, bs);
277	l->touched_dirtied = 1;
278}
279
280/*
281 *---------------------------------------------------------------
282 * Header IO
283 *--------------------------------------------------------------
284 */
285static void header_to_disk(struct log_header_core *core, struct log_header_disk *disk)
286{
287	disk->magic = cpu_to_le32(core->magic);
288	disk->version = cpu_to_le32(core->version);
289	disk->nr_regions = cpu_to_le64(core->nr_regions);
290}
291
292static void header_from_disk(struct log_header_core *core, struct log_header_disk *disk)
293{
294	core->magic = le32_to_cpu(disk->magic);
295	core->version = le32_to_cpu(disk->version);
296	core->nr_regions = le64_to_cpu(disk->nr_regions);
297}
298
299static int rw_header(struct log_c *lc, enum req_op op)
300{
301	lc->io_req.bi_opf = op;
302
303	return dm_io(&lc->io_req, 1, &lc->header_location, NULL, IOPRIO_DEFAULT);
304}
305
306static int flush_header(struct log_c *lc)
307{
308	struct dm_io_region null_location = {
309		.bdev = lc->header_location.bdev,
310		.sector = 0,
311		.count = 0,
312	};
313
314	lc->io_req.bi_opf = REQ_OP_WRITE | REQ_PREFLUSH;
315
316	return dm_io(&lc->io_req, 1, &null_location, NULL, IOPRIO_DEFAULT);
317}
318
319static int read_header(struct log_c *log)
320{
321	int r;
322
323	r = rw_header(log, REQ_OP_READ);
324	if (r)
325		return r;
326
327	header_from_disk(&log->header, log->disk_header);
328
329	/* New log required? */
330	if (log->sync != DEFAULTSYNC || log->header.magic != MIRROR_MAGIC) {
331		log->header.magic = MIRROR_MAGIC;
332		log->header.version = MIRROR_DISK_VERSION;
333		log->header.nr_regions = 0;
334	}
335
336#ifdef __LITTLE_ENDIAN
337	if (log->header.version == 1)
338		log->header.version = 2;
339#endif
340
341	if (log->header.version != MIRROR_DISK_VERSION) {
342		DMWARN("incompatible disk log version");
343		return -EINVAL;
344	}
345
346	return 0;
347}
348
349static int _check_region_size(struct dm_target *ti, uint32_t region_size)
350{
351	if (region_size < 2 || region_size > ti->len)
352		return 0;
353
354	if (!is_power_of_2(region_size))
355		return 0;
356
357	return 1;
358}
359
360/*
361 *--------------------------------------------------------------
362 * core log constructor/destructor
363 *
364 * argv contains region_size followed optionally by [no]sync
365 *--------------------------------------------------------------
366 */
367#define BYTE_SHIFT 3
368static int create_log_context(struct dm_dirty_log *log, struct dm_target *ti,
369			      unsigned int argc, char **argv,
370			      struct dm_dev *dev)
371{
372	enum sync sync = DEFAULTSYNC;
373
374	struct log_c *lc;
375	uint32_t region_size;
376	unsigned int region_count;
377	size_t bitset_size, buf_size;
378	int r;
379	char dummy;
380
381	if (argc < 1 || argc > 2) {
382		DMWARN("wrong number of arguments to dirty region log");
383		return -EINVAL;
384	}
385
386	if (argc > 1) {
387		if (!strcmp(argv[1], "sync"))
388			sync = FORCESYNC;
389		else if (!strcmp(argv[1], "nosync"))
390			sync = NOSYNC;
391		else {
392			DMWARN("unrecognised sync argument to dirty region log: %s", argv[1]);
393			return -EINVAL;
394		}
395	}
396
397	if (sscanf(argv[0], "%u%c", &region_size, &dummy) != 1 ||
398	    !_check_region_size(ti, region_size)) {
399		DMWARN("invalid region size %s", argv[0]);
400		return -EINVAL;
401	}
402
403	region_count = dm_sector_div_up(ti->len, region_size);
404
405	lc = kmalloc(sizeof(*lc), GFP_KERNEL);
406	if (!lc) {
407		DMWARN("couldn't allocate core log");
408		return -ENOMEM;
409	}
410
411	lc->ti = ti;
412	lc->touched_dirtied = 0;
413	lc->touched_cleaned = 0;
414	lc->flush_failed = 0;
415	lc->region_size = region_size;
416	lc->region_count = region_count;
417	lc->sync = sync;
418
419	/*
420	 * Work out how many "unsigned long"s we need to hold the bitset.
421	 */
422	bitset_size = dm_round_up(region_count, BITS_PER_LONG);
423	bitset_size >>= BYTE_SHIFT;
424
425	lc->bitset_uint32_count = bitset_size / sizeof(*lc->clean_bits);
426
427	/*
428	 * Disk log?
429	 */
430	if (!dev) {
431		lc->clean_bits = vmalloc(bitset_size);
432		if (!lc->clean_bits) {
433			DMWARN("couldn't allocate clean bitset");
434			kfree(lc);
435			return -ENOMEM;
436		}
437		lc->disk_header = NULL;
438	} else {
439		lc->log_dev = dev;
440		lc->log_dev_failed = 0;
441		lc->log_dev_flush_failed = 0;
442		lc->header_location.bdev = lc->log_dev->bdev;
443		lc->header_location.sector = 0;
444
445		/*
446		 * Buffer holds both header and bitset.
447		 */
448		buf_size =
449		    dm_round_up((LOG_OFFSET << SECTOR_SHIFT) + bitset_size,
450				bdev_logical_block_size(lc->header_location.bdev));
451
452		if (buf_size > bdev_nr_bytes(dev->bdev)) {
453			DMWARN("log device %s too small: need %llu bytes",
454				dev->name, (unsigned long long)buf_size);
455			kfree(lc);
456			return -EINVAL;
457		}
458
459		lc->header_location.count = buf_size >> SECTOR_SHIFT;
460
461		lc->io_req.mem.type = DM_IO_VMA;
462		lc->io_req.notify.fn = NULL;
463		lc->io_req.client = dm_io_client_create();
464		if (IS_ERR(lc->io_req.client)) {
465			r = PTR_ERR(lc->io_req.client);
466			DMWARN("couldn't allocate disk io client");
467			kfree(lc);
468			return r;
469		}
470
471		lc->disk_header = vmalloc(buf_size);
472		if (!lc->disk_header) {
473			DMWARN("couldn't allocate disk log buffer");
474			dm_io_client_destroy(lc->io_req.client);
475			kfree(lc);
476			return -ENOMEM;
477		}
478
479		lc->io_req.mem.ptr.vma = lc->disk_header;
480		lc->clean_bits = (void *)lc->disk_header +
481				 (LOG_OFFSET << SECTOR_SHIFT);
482	}
483
484	memset(lc->clean_bits, -1, bitset_size);
485
486	lc->sync_bits = vmalloc(bitset_size);
487	if (!lc->sync_bits) {
488		DMWARN("couldn't allocate sync bitset");
489		if (!dev)
490			vfree(lc->clean_bits);
491		else
492			dm_io_client_destroy(lc->io_req.client);
493		vfree(lc->disk_header);
494		kfree(lc);
495		return -ENOMEM;
496	}
497	memset(lc->sync_bits, (sync == NOSYNC) ? -1 : 0, bitset_size);
498	lc->sync_count = (sync == NOSYNC) ? region_count : 0;
499
500	lc->recovering_bits = vzalloc(bitset_size);
501	if (!lc->recovering_bits) {
502		DMWARN("couldn't allocate sync bitset");
503		vfree(lc->sync_bits);
504		if (!dev)
505			vfree(lc->clean_bits);
506		else
507			dm_io_client_destroy(lc->io_req.client);
508		vfree(lc->disk_header);
509		kfree(lc);
510		return -ENOMEM;
511	}
512	lc->sync_search = 0;
513	log->context = lc;
514
515	return 0;
516}
517
518static int core_ctr(struct dm_dirty_log *log, struct dm_target *ti,
519		    unsigned int argc, char **argv)
520{
521	return create_log_context(log, ti, argc, argv, NULL);
522}
523
524static void destroy_log_context(struct log_c *lc)
525{
526	vfree(lc->sync_bits);
527	vfree(lc->recovering_bits);
528	kfree(lc);
529}
530
531static void core_dtr(struct dm_dirty_log *log)
532{
533	struct log_c *lc = log->context;
534
535	vfree(lc->clean_bits);
536	destroy_log_context(lc);
537}
538
539/*
540 *---------------------------------------------------------------------
541 * disk log constructor/destructor
542 *
543 * argv contains log_device region_size followed optionally by [no]sync
544 *---------------------------------------------------------------------
545 */
546static int disk_ctr(struct dm_dirty_log *log, struct dm_target *ti,
547		    unsigned int argc, char **argv)
548{
549	int r;
550	struct dm_dev *dev;
551
552	if (argc < 2 || argc > 3) {
553		DMWARN("wrong number of arguments to disk dirty region log");
554		return -EINVAL;
555	}
556
557	r = dm_get_device(ti, argv[0], dm_table_get_mode(ti->table), &dev);
558	if (r)
559		return r;
560
561	r = create_log_context(log, ti, argc - 1, argv + 1, dev);
562	if (r) {
563		dm_put_device(ti, dev);
564		return r;
565	}
566
567	return 0;
568}
569
570static void disk_dtr(struct dm_dirty_log *log)
571{
572	struct log_c *lc = log->context;
573
574	dm_put_device(lc->ti, lc->log_dev);
575	vfree(lc->disk_header);
576	dm_io_client_destroy(lc->io_req.client);
577	destroy_log_context(lc);
578}
579
580static void fail_log_device(struct log_c *lc)
581{
582	if (lc->log_dev_failed)
583		return;
584
585	lc->log_dev_failed = 1;
586	dm_table_event(lc->ti->table);
587}
588
589static int disk_resume(struct dm_dirty_log *log)
590{
591	int r;
592	unsigned int i;
593	struct log_c *lc = log->context;
594	size_t size = lc->bitset_uint32_count * sizeof(uint32_t);
595
596	/* read the disk header */
597	r = read_header(lc);
598	if (r) {
599		DMWARN("%s: Failed to read header on dirty region log device",
600		       lc->log_dev->name);
601		fail_log_device(lc);
602		/*
603		 * If the log device cannot be read, we must assume
604		 * all regions are out-of-sync.  If we simply return
605		 * here, the state will be uninitialized and could
606		 * lead us to return 'in-sync' status for regions
607		 * that are actually 'out-of-sync'.
608		 */
609		lc->header.nr_regions = 0;
610	}
611
612	/* set or clear any new bits -- device has grown */
613	if (lc->sync == NOSYNC)
614		for (i = lc->header.nr_regions; i < lc->region_count; i++)
615			/* FIXME: amazingly inefficient */
616			log_set_bit(lc, lc->clean_bits, i);
617	else
618		for (i = lc->header.nr_regions; i < lc->region_count; i++)
619			/* FIXME: amazingly inefficient */
620			log_clear_bit(lc, lc->clean_bits, i);
621
622	/* clear any old bits -- device has shrunk */
623	for (i = lc->region_count; i % BITS_PER_LONG; i++)
624		log_clear_bit(lc, lc->clean_bits, i);
625
626	/* copy clean across to sync */
627	memcpy(lc->sync_bits, lc->clean_bits, size);
628	lc->sync_count = memweight(lc->clean_bits,
629				lc->bitset_uint32_count * sizeof(uint32_t));
630	lc->sync_search = 0;
631
632	/* set the correct number of regions in the header */
633	lc->header.nr_regions = lc->region_count;
634
635	header_to_disk(&lc->header, lc->disk_header);
636
637	/* write the new header */
638	r = rw_header(lc, REQ_OP_WRITE);
639	if (!r) {
640		r = flush_header(lc);
641		if (r)
642			lc->log_dev_flush_failed = 1;
643	}
644	if (r) {
645		DMWARN("%s: Failed to write header on dirty region log device",
646		       lc->log_dev->name);
647		fail_log_device(lc);
648	}
649
650	return r;
651}
652
653static uint32_t core_get_region_size(struct dm_dirty_log *log)
654{
655	struct log_c *lc = log->context;
656
657	return lc->region_size;
658}
659
660static int core_resume(struct dm_dirty_log *log)
661{
662	struct log_c *lc = log->context;
663
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 = log->context;
671
672	return log_test_bit(lc->clean_bits, region);
673}
674
675static int core_in_sync(struct dm_dirty_log *log, region_t region, int block)
676{
677	struct log_c *lc = log->context;
678
679	return log_test_bit(lc->sync_bits, region);
680}
681
682static int core_flush(struct dm_dirty_log *log)
683{
684	/* no op */
685	return 0;
686}
687
688static int disk_flush(struct dm_dirty_log *log)
689{
690	int r, i;
691	struct log_c *lc = log->context;
692
693	/* only write if the log has changed */
694	if (!lc->touched_cleaned && !lc->touched_dirtied)
695		return 0;
696
697	if (lc->touched_cleaned && log->flush_callback_fn &&
698	    log->flush_callback_fn(lc->ti)) {
699		/*
700		 * At this point it is impossible to determine which
701		 * regions are clean and which are dirty (without
702		 * re-reading the log off disk). So mark all of them
703		 * dirty.
704		 */
705		lc->flush_failed = 1;
706		for (i = 0; i < lc->region_count; i++)
707			log_clear_bit(lc, lc->clean_bits, i);
708	}
709
710	r = rw_header(lc, REQ_OP_WRITE);
711	if (r)
712		fail_log_device(lc);
713	else {
714		if (lc->touched_dirtied) {
715			r = flush_header(lc);
716			if (r) {
717				lc->log_dev_flush_failed = 1;
718				fail_log_device(lc);
719			} else
720				lc->touched_dirtied = 0;
721		}
722		lc->touched_cleaned = 0;
723	}
724
725	return r;
726}
727
728static void core_mark_region(struct dm_dirty_log *log, region_t region)
729{
730	struct log_c *lc = log->context;
731
732	log_clear_bit(lc, lc->clean_bits, region);
733}
734
735static void core_clear_region(struct dm_dirty_log *log, region_t region)
736{
737	struct log_c *lc = log->context;
738
739	if (likely(!lc->flush_failed))
740		log_set_bit(lc, lc->clean_bits, region);
741}
742
743static int core_get_resync_work(struct dm_dirty_log *log, region_t *region)
744{
745	struct log_c *lc = log->context;
746
747	if (lc->sync_search >= lc->region_count)
748		return 0;
749
750	do {
751		*region = find_next_zero_bit_le(lc->sync_bits,
752					     lc->region_count,
753					     lc->sync_search);
754		lc->sync_search = *region + 1;
755
756		if (*region >= lc->region_count)
757			return 0;
758
759	} while (log_test_bit(lc->recovering_bits, *region));
760
761	log_set_bit(lc, lc->recovering_bits, *region);
762	return 1;
763}
764
765static void core_set_region_sync(struct dm_dirty_log *log, region_t region,
766				 int in_sync)
767{
768	struct log_c *lc = log->context;
769
770	log_clear_bit(lc, lc->recovering_bits, region);
771	if (in_sync) {
772		log_set_bit(lc, lc->sync_bits, region);
773		lc->sync_count++;
774	} else if (log_test_bit(lc->sync_bits, region)) {
775		lc->sync_count--;
776		log_clear_bit(lc, lc->sync_bits, region);
777	}
778}
779
780static region_t core_get_sync_count(struct dm_dirty_log *log)
781{
782	struct log_c *lc = log->context;
783
784	return lc->sync_count;
785}
786
787#define	DMEMIT_SYNC \
788	do { \
789		if (lc->sync != DEFAULTSYNC) \
790			DMEMIT("%ssync ", lc->sync == NOSYNC ? "no" : ""); \
791	} while (0)
792
793static int core_status(struct dm_dirty_log *log, status_type_t status,
794		       char *result, unsigned int maxlen)
795{
796	int sz = 0;
797	struct log_c *lc = log->context;
798
799	switch (status) {
800	case STATUSTYPE_INFO:
801		DMEMIT("1 %s", log->type->name);
802		break;
803
804	case STATUSTYPE_TABLE:
805		DMEMIT("%s %u %u ", log->type->name,
806		       lc->sync == DEFAULTSYNC ? 1 : 2, lc->region_size);
807		DMEMIT_SYNC;
808		break;
809
810	case STATUSTYPE_IMA:
811		*result = '\0';
812		break;
813	}
814
815	return sz;
816}
817
818static int disk_status(struct dm_dirty_log *log, status_type_t status,
819		       char *result, unsigned int maxlen)
820{
821	int sz = 0;
822	struct log_c *lc = log->context;
823
824	switch (status) {
825	case STATUSTYPE_INFO:
826		DMEMIT("3 %s %s %c", log->type->name, lc->log_dev->name,
827		       lc->log_dev_flush_failed ? 'F' :
828		       lc->log_dev_failed ? 'D' :
829		       'A');
830		break;
831
832	case STATUSTYPE_TABLE:
833		DMEMIT("%s %u %s %u ", log->type->name,
834		       lc->sync == DEFAULTSYNC ? 2 : 3, lc->log_dev->name,
835		       lc->region_size);
836		DMEMIT_SYNC;
837		break;
838
839	case STATUSTYPE_IMA:
840		*result = '\0';
841		break;
842	}
843
844	return sz;
845}
846
847static struct dm_dirty_log_type _core_type = {
848	.name = "core",
849	.module = THIS_MODULE,
850	.ctr = core_ctr,
851	.dtr = core_dtr,
852	.resume = core_resume,
853	.get_region_size = core_get_region_size,
854	.is_clean = core_is_clean,
855	.in_sync = core_in_sync,
856	.flush = core_flush,
857	.mark_region = core_mark_region,
858	.clear_region = core_clear_region,
859	.get_resync_work = core_get_resync_work,
860	.set_region_sync = core_set_region_sync,
861	.get_sync_count = core_get_sync_count,
862	.status = core_status,
863};
864
865static struct dm_dirty_log_type _disk_type = {
866	.name = "disk",
867	.module = THIS_MODULE,
868	.ctr = disk_ctr,
869	.dtr = disk_dtr,
870	.postsuspend = disk_flush,
871	.resume = disk_resume,
872	.get_region_size = core_get_region_size,
873	.is_clean = core_is_clean,
874	.in_sync = core_in_sync,
875	.flush = disk_flush,
876	.mark_region = core_mark_region,
877	.clear_region = core_clear_region,
878	.get_resync_work = core_get_resync_work,
879	.set_region_sync = core_set_region_sync,
880	.get_sync_count = core_get_sync_count,
881	.status = disk_status,
882};
883
884static int __init dm_dirty_log_init(void)
885{
886	int r;
887
888	r = dm_dirty_log_type_register(&_core_type);
889	if (r)
890		DMWARN("couldn't register core log");
891
892	r = dm_dirty_log_type_register(&_disk_type);
893	if (r) {
894		DMWARN("couldn't register disk type");
895		dm_dirty_log_type_unregister(&_core_type);
896	}
897
898	return r;
899}
900
901static void __exit dm_dirty_log_exit(void)
902{
903	dm_dirty_log_type_unregister(&_disk_type);
904	dm_dirty_log_type_unregister(&_core_type);
905}
906
907module_init(dm_dirty_log_init);
908module_exit(dm_dirty_log_exit);
909
910MODULE_DESCRIPTION(DM_NAME " dirty region log");
911MODULE_AUTHOR("Joe Thornber, Heinz Mauelshagen <dm-devel@lists.linux.dev>");
912MODULE_LICENSE("GPL");
913