blob: a66428d860fef830d3fddc6d8f48140d7a646a4b [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * Copyright (C) 2003 Sistina Software
3 *
4 * This file is released under the LGPL.
5 */
6
7#include <linux/init.h>
8#include <linux/slab.h>
9#include <linux/module.h>
10#include <linux/vmalloc.h>
11
12#include "dm-log.h"
13#include "dm-io.h"
14
Alasdair G Kergon72d94862006-06-26 00:27:35 -070015#define DM_MSG_PREFIX "mirror log"
16
Linus Torvalds1da177e2005-04-16 15:20:36 -070017static LIST_HEAD(_log_types);
18static DEFINE_SPINLOCK(_lock);
19
20int dm_register_dirty_log_type(struct dirty_log_type *type)
21{
22 spin_lock(&_lock);
23 type->use_count = 0;
24 list_add(&type->list, &_log_types);
25 spin_unlock(&_lock);
26
27 return 0;
28}
29
30int dm_unregister_dirty_log_type(struct dirty_log_type *type)
31{
32 spin_lock(&_lock);
33
34 if (type->use_count)
35 DMWARN("Attempt to unregister a log type that is still in use");
36 else
37 list_del(&type->list);
38
39 spin_unlock(&_lock);
40
41 return 0;
42}
43
44static struct dirty_log_type *get_type(const char *type_name)
45{
46 struct dirty_log_type *type;
47
48 spin_lock(&_lock);
49 list_for_each_entry (type, &_log_types, list)
50 if (!strcmp(type_name, type->name)) {
51 if (!type->use_count && !try_module_get(type->module)){
52 spin_unlock(&_lock);
53 return NULL;
54 }
55 type->use_count++;
56 spin_unlock(&_lock);
57 return type;
58 }
59
60 spin_unlock(&_lock);
61 return NULL;
62}
63
64static void put_type(struct dirty_log_type *type)
65{
66 spin_lock(&_lock);
67 if (!--type->use_count)
68 module_put(type->module);
69 spin_unlock(&_lock);
70}
71
72struct dirty_log *dm_create_dirty_log(const char *type_name, struct dm_target *ti,
73 unsigned int argc, char **argv)
74{
75 struct dirty_log_type *type;
76 struct dirty_log *log;
77
78 log = kmalloc(sizeof(*log), GFP_KERNEL);
79 if (!log)
80 return NULL;
81
82 type = get_type(type_name);
83 if (!type) {
84 kfree(log);
85 return NULL;
86 }
87
88 log->type = type;
89 if (type->ctr(log, ti, argc, argv)) {
90 kfree(log);
91 put_type(type);
92 return NULL;
93 }
94
95 return log;
96}
97
98void dm_destroy_dirty_log(struct dirty_log *log)
99{
100 log->type->dtr(log);
101 put_type(log->type);
102 kfree(log);
103}
104
105/*-----------------------------------------------------------------
106 * Persistent and core logs share a lot of their implementation.
107 * FIXME: need a reload method to be called from a resume
108 *---------------------------------------------------------------*/
109/*
110 * Magic for persistent mirrors: "MiRr"
111 */
112#define MIRROR_MAGIC 0x4D695272
113
114/*
115 * The on-disk version of the metadata.
116 */
Patrick Caulfielda4fc4712006-02-01 03:04:51 -0800117#define MIRROR_DISK_VERSION 2
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118#define LOG_OFFSET 2
119
120struct log_header {
121 uint32_t magic;
122
123 /*
124 * Simple, incrementing version. no backward
125 * compatibility.
126 */
127 uint32_t version;
128 sector_t nr_regions;
129};
130
131struct log_c {
132 struct dm_target *ti;
133 int touched;
134 uint32_t region_size;
135 unsigned int region_count;
136 region_t sync_count;
137
138 unsigned bitset_uint32_count;
139 uint32_t *clean_bits;
140 uint32_t *sync_bits;
141 uint32_t *recovering_bits; /* FIXME: this seems excessive */
142
143 int sync_search;
144
145 /* Resync flag */
146 enum sync {
147 DEFAULTSYNC, /* Synchronize if necessary */
148 NOSYNC, /* Devices known to be already in sync */
149 FORCESYNC, /* Force a sync to happen */
150 } sync;
151
Heinz Mauelshagen5d234d12007-05-09 02:33:03 -0700152 struct dm_io_request io_req;
153
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154 /*
155 * Disk log fields
156 */
Jonathan E Brassow01d03a62007-05-09 02:32:57 -0700157 int log_dev_failed;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700158 struct dm_dev *log_dev;
159 struct log_header header;
160
161 struct io_region header_location;
162 struct log_header *disk_header;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700163};
164
165/*
166 * The touched member needs to be updated every time we access
167 * one of the bitsets.
168 */
169static inline int log_test_bit(uint32_t *bs, unsigned bit)
170{
Patrick Caulfielda4fc4712006-02-01 03:04:51 -0800171 return ext2_test_bit(bit, (unsigned long *) bs) ? 1 : 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700172}
173
174static inline void log_set_bit(struct log_c *l,
175 uint32_t *bs, unsigned bit)
176{
Patrick Caulfielda4fc4712006-02-01 03:04:51 -0800177 ext2_set_bit(bit, (unsigned long *) bs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700178 l->touched = 1;
179}
180
181static inline void log_clear_bit(struct log_c *l,
182 uint32_t *bs, unsigned bit)
183{
Patrick Caulfielda4fc4712006-02-01 03:04:51 -0800184 ext2_clear_bit(bit, (unsigned long *) bs);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185 l->touched = 1;
186}
187
188/*----------------------------------------------------------------
189 * Header IO
190 *--------------------------------------------------------------*/
191static void header_to_disk(struct log_header *core, struct log_header *disk)
192{
193 disk->magic = cpu_to_le32(core->magic);
194 disk->version = cpu_to_le32(core->version);
195 disk->nr_regions = cpu_to_le64(core->nr_regions);
196}
197
198static void header_from_disk(struct log_header *core, struct log_header *disk)
199{
200 core->magic = le32_to_cpu(disk->magic);
201 core->version = le32_to_cpu(disk->version);
202 core->nr_regions = le64_to_cpu(disk->nr_regions);
203}
204
Heinz Mauelshagen5d234d12007-05-09 02:33:03 -0700205static int rw_header(struct log_c *lc, int rw)
206{
207 lc->io_req.bi_rw = rw;
208 lc->io_req.mem.ptr.vma = lc->disk_header;
209 lc->io_req.notify.fn = NULL;
210
211 return dm_io(&lc->io_req, 1, &lc->header_location, NULL);
212}
213
Linus Torvalds1da177e2005-04-16 15:20:36 -0700214static int read_header(struct log_c *log)
215{
216 int r;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217
Heinz Mauelshagen5d234d12007-05-09 02:33:03 -0700218 r = rw_header(log, READ);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700219 if (r)
220 return r;
221
222 header_from_disk(&log->header, log->disk_header);
223
224 /* New log required? */
225 if (log->sync != DEFAULTSYNC || log->header.magic != MIRROR_MAGIC) {
226 log->header.magic = MIRROR_MAGIC;
227 log->header.version = MIRROR_DISK_VERSION;
228 log->header.nr_regions = 0;
229 }
230
Patrick Caulfielda4fc4712006-02-01 03:04:51 -0800231#ifdef __LITTLE_ENDIAN
232 if (log->header.version == 1)
233 log->header.version = 2;
234#endif
235
Linus Torvalds1da177e2005-04-16 15:20:36 -0700236 if (log->header.version != MIRROR_DISK_VERSION) {
237 DMWARN("incompatible disk log version");
238 return -EINVAL;
239 }
240
241 return 0;
242}
243
244static inline int write_header(struct log_c *log)
245{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700246 header_to_disk(&log->header, log->disk_header);
Heinz Mauelshagen5d234d12007-05-09 02:33:03 -0700247 return rw_header(log, WRITE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700248}
249
250/*----------------------------------------------------------------
Linus Torvalds1da177e2005-04-16 15:20:36 -0700251 * core log constructor/destructor
252 *
253 * argv contains region_size followed optionally by [no]sync
254 *--------------------------------------------------------------*/
255#define BYTE_SHIFT 3
Alasdair G Kergonb7cca192006-06-26 00:27:29 -0700256static int create_log_context(struct dirty_log *log, struct dm_target *ti,
257 unsigned int argc, char **argv,
258 struct dm_dev *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700259{
260 enum sync sync = DEFAULTSYNC;
261
262 struct log_c *lc;
263 uint32_t region_size;
264 unsigned int region_count;
Alasdair G Kergonb7cca192006-06-26 00:27:29 -0700265 size_t bitset_size, buf_size;
Heinz Mauelshagen5d234d12007-05-09 02:33:03 -0700266 int r;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700267
268 if (argc < 1 || argc > 2) {
269 DMWARN("wrong number of arguments to mirror log");
270 return -EINVAL;
271 }
272
273 if (argc > 1) {
274 if (!strcmp(argv[1], "sync"))
275 sync = FORCESYNC;
276 else if (!strcmp(argv[1], "nosync"))
277 sync = NOSYNC;
278 else {
279 DMWARN("unrecognised sync argument to mirror log: %s",
280 argv[1]);
281 return -EINVAL;
282 }
283 }
284
285 if (sscanf(argv[0], "%u", &region_size) != 1) {
286 DMWARN("invalid region size string");
287 return -EINVAL;
288 }
289
290 region_count = dm_sector_div_up(ti->len, region_size);
291
292 lc = kmalloc(sizeof(*lc), GFP_KERNEL);
293 if (!lc) {
294 DMWARN("couldn't allocate core log");
295 return -ENOMEM;
296 }
297
298 lc->ti = ti;
299 lc->touched = 0;
300 lc->region_size = region_size;
301 lc->region_count = region_count;
302 lc->sync = sync;
303
304 /*
Alasdair G Kergon0e568222005-11-21 21:32:34 -0800305 * Work out how many "unsigned long"s we need to hold the bitset.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700306 */
307 bitset_size = dm_round_up(region_count,
Alasdair G Kergon29121bd2006-06-26 00:27:29 -0700308 sizeof(*lc->clean_bits) << BYTE_SHIFT);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700309 bitset_size >>= BYTE_SHIFT;
310
Alasdair G Kergon29121bd2006-06-26 00:27:29 -0700311 lc->bitset_uint32_count = bitset_size / sizeof(*lc->clean_bits);
Alasdair G Kergonb7cca192006-06-26 00:27:29 -0700312
313 /*
314 * Disk log?
315 */
316 if (!dev) {
317 lc->clean_bits = vmalloc(bitset_size);
318 if (!lc->clean_bits) {
319 DMWARN("couldn't allocate clean bitset");
320 kfree(lc);
321 return -ENOMEM;
322 }
323 lc->disk_header = NULL;
324 } else {
325 lc->log_dev = dev;
Jonathan E Brassow01d03a62007-05-09 02:32:57 -0700326 lc->log_dev_failed = 0;
Alasdair G Kergonb7cca192006-06-26 00:27:29 -0700327 lc->header_location.bdev = lc->log_dev->bdev;
328 lc->header_location.sector = 0;
329
330 /*
331 * Buffer holds both header and bitset.
332 */
333 buf_size = dm_round_up((LOG_OFFSET << SECTOR_SHIFT) +
334 bitset_size, ti->limits.hardsect_size);
335 lc->header_location.count = buf_size >> SECTOR_SHIFT;
Heinz Mauelshagen5d234d12007-05-09 02:33:03 -0700336 lc->io_req.mem.type = DM_IO_VMA;
337 lc->io_req.client = dm_io_client_create(dm_div_up(buf_size,
338 PAGE_SIZE));
339 if (IS_ERR(lc->io_req.client)) {
340 r = PTR_ERR(lc->io_req.client);
341 DMWARN("couldn't allocate disk io client");
342 kfree(lc);
343 return -ENOMEM;
344 }
Alasdair G Kergonb7cca192006-06-26 00:27:29 -0700345
346 lc->disk_header = vmalloc(buf_size);
347 if (!lc->disk_header) {
348 DMWARN("couldn't allocate disk log buffer");
349 kfree(lc);
350 return -ENOMEM;
351 }
352
353 lc->clean_bits = (void *)lc->disk_header +
354 (LOG_OFFSET << SECTOR_SHIFT);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355 }
Alasdair G Kergonb7cca192006-06-26 00:27:29 -0700356
Linus Torvalds1da177e2005-04-16 15:20:36 -0700357 memset(lc->clean_bits, -1, bitset_size);
358
359 lc->sync_bits = vmalloc(bitset_size);
360 if (!lc->sync_bits) {
361 DMWARN("couldn't allocate sync bitset");
Alasdair G Kergonb7cca192006-06-26 00:27:29 -0700362 if (!dev)
363 vfree(lc->clean_bits);
364 vfree(lc->disk_header);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700365 kfree(lc);
366 return -ENOMEM;
367 }
368 memset(lc->sync_bits, (sync == NOSYNC) ? -1 : 0, bitset_size);
369 lc->sync_count = (sync == NOSYNC) ? region_count : 0;
370
371 lc->recovering_bits = vmalloc(bitset_size);
372 if (!lc->recovering_bits) {
373 DMWARN("couldn't allocate sync bitset");
374 vfree(lc->sync_bits);
Alasdair G Kergonb7cca192006-06-26 00:27:29 -0700375 if (!dev)
376 vfree(lc->clean_bits);
377 vfree(lc->disk_header);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700378 kfree(lc);
379 return -ENOMEM;
380 }
381 memset(lc->recovering_bits, 0, bitset_size);
382 lc->sync_search = 0;
383 log->context = lc;
Alasdair G Kergonb7cca192006-06-26 00:27:29 -0700384
Linus Torvalds1da177e2005-04-16 15:20:36 -0700385 return 0;
386}
387
Alasdair G Kergonb7cca192006-06-26 00:27:29 -0700388static int core_ctr(struct dirty_log *log, struct dm_target *ti,
389 unsigned int argc, char **argv)
390{
391 return create_log_context(log, ti, argc, argv, NULL);
392}
393
394static void destroy_log_context(struct log_c *lc)
395{
396 vfree(lc->sync_bits);
397 vfree(lc->recovering_bits);
398 kfree(lc);
399}
400
Linus Torvalds1da177e2005-04-16 15:20:36 -0700401static void core_dtr(struct dirty_log *log)
402{
403 struct log_c *lc = (struct log_c *) log->context;
Alasdair G Kergonb7cca192006-06-26 00:27:29 -0700404
Linus Torvalds1da177e2005-04-16 15:20:36 -0700405 vfree(lc->clean_bits);
Alasdair G Kergonb7cca192006-06-26 00:27:29 -0700406 destroy_log_context(lc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407}
408
409/*----------------------------------------------------------------
410 * disk log constructor/destructor
411 *
412 * argv contains log_device region_size followed optionally by [no]sync
413 *--------------------------------------------------------------*/
414static int disk_ctr(struct dirty_log *log, struct dm_target *ti,
415 unsigned int argc, char **argv)
416{
417 int r;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700418 struct dm_dev *dev;
419
420 if (argc < 2 || argc > 3) {
421 DMWARN("wrong number of arguments to disk mirror log");
422 return -EINVAL;
423 }
424
425 r = dm_get_device(ti, argv[0], 0, 0 /* FIXME */,
426 FMODE_READ | FMODE_WRITE, &dev);
427 if (r)
428 return r;
429
Alasdair G Kergonb7cca192006-06-26 00:27:29 -0700430 r = create_log_context(log, ti, argc - 1, argv + 1, dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700431 if (r) {
432 dm_put_device(ti, dev);
433 return r;
434 }
435
Linus Torvalds1da177e2005-04-16 15:20:36 -0700436 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700437}
438
439static void disk_dtr(struct dirty_log *log)
440{
441 struct log_c *lc = (struct log_c *) log->context;
Alasdair G Kergonb7cca192006-06-26 00:27:29 -0700442
Linus Torvalds1da177e2005-04-16 15:20:36 -0700443 dm_put_device(lc->ti, lc->log_dev);
444 vfree(lc->disk_header);
Heinz Mauelshagen5d234d12007-05-09 02:33:03 -0700445 dm_io_client_destroy(lc->io_req.client);
Alasdair G Kergonb7cca192006-06-26 00:27:29 -0700446 destroy_log_context(lc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700447}
448
449static int count_bits32(uint32_t *addr, unsigned size)
450{
451 int count = 0, i;
452
453 for (i = 0; i < size; i++) {
454 count += hweight32(*(addr+i));
455 }
456 return count;
457}
458
Jonathan E Brassow01d03a62007-05-09 02:32:57 -0700459static void fail_log_device(struct log_c *lc)
460{
461 if (lc->log_dev_failed)
462 return;
463
464 lc->log_dev_failed = 1;
465 dm_table_event(lc->ti->table);
466}
467
Linus Torvalds1da177e2005-04-16 15:20:36 -0700468static int disk_resume(struct dirty_log *log)
469{
470 int r;
471 unsigned i;
472 struct log_c *lc = (struct log_c *) log->context;
473 size_t size = lc->bitset_uint32_count * sizeof(uint32_t);
474
475 /* read the disk header */
476 r = read_header(lc);
Jonathan E Brassow01d03a62007-05-09 02:32:57 -0700477 if (r) {
478 DMWARN("%s: Failed to read header on mirror log device",
479 lc->log_dev->name);
480 fail_log_device(lc);
Jonathan Brassowba8b45c2007-05-09 02:33:08 -0700481 /*
482 * If the log device cannot be read, we must assume
483 * all regions are out-of-sync. If we simply return
484 * here, the state will be uninitialized and could
485 * lead us to return 'in-sync' status for regions
486 * that are actually 'out-of-sync'.
487 */
488 lc->header.nr_regions = 0;
Jonathan E Brassow01d03a62007-05-09 02:32:57 -0700489 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700490
Alasdair G Kergon8a835f12006-06-26 00:27:30 -0700491 /* set or clear any new bits -- device has grown */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700492 if (lc->sync == NOSYNC)
493 for (i = lc->header.nr_regions; i < lc->region_count; i++)
494 /* FIXME: amazingly inefficient */
495 log_set_bit(lc, lc->clean_bits, i);
496 else
497 for (i = lc->header.nr_regions; i < lc->region_count; i++)
498 /* FIXME: amazingly inefficient */
499 log_clear_bit(lc, lc->clean_bits, i);
500
Alasdair G Kergon8a835f12006-06-26 00:27:30 -0700501 /* clear any old bits -- device has shrunk */
502 for (i = lc->region_count; i % (sizeof(*lc->clean_bits) << BYTE_SHIFT); i++)
503 log_clear_bit(lc, lc->clean_bits, i);
504
Linus Torvalds1da177e2005-04-16 15:20:36 -0700505 /* copy clean across to sync */
506 memcpy(lc->sync_bits, lc->clean_bits, size);
507 lc->sync_count = count_bits32(lc->clean_bits, lc->bitset_uint32_count);
Jonathan E Brassow88b20a12006-12-08 02:41:12 -0800508 lc->sync_search = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700509
Linus Torvalds1da177e2005-04-16 15:20:36 -0700510 /* set the correct number of regions in the header */
511 lc->header.nr_regions = lc->region_count;
512
513 /* write the new header */
Jonathan E Brassow01d03a62007-05-09 02:32:57 -0700514 r = write_header(lc);
515 if (r) {
516 DMWARN("%s: Failed to write header on mirror log device",
517 lc->log_dev->name);
518 fail_log_device(lc);
519 }
520
521 return r;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700522}
523
524static uint32_t core_get_region_size(struct dirty_log *log)
525{
526 struct log_c *lc = (struct log_c *) log->context;
527 return lc->region_size;
528}
529
Jonathan E Brassow88b20a12006-12-08 02:41:12 -0800530static int core_resume(struct dirty_log *log)
531{
532 struct log_c *lc = (struct log_c *) log->context;
533 lc->sync_search = 0;
534 return 0;
535}
536
Linus Torvalds1da177e2005-04-16 15:20:36 -0700537static int core_is_clean(struct dirty_log *log, region_t region)
538{
539 struct log_c *lc = (struct log_c *) log->context;
540 return log_test_bit(lc->clean_bits, region);
541}
542
543static int core_in_sync(struct dirty_log *log, region_t region, int block)
544{
545 struct log_c *lc = (struct log_c *) log->context;
546 return log_test_bit(lc->sync_bits, region);
547}
548
549static int core_flush(struct dirty_log *log)
550{
551 /* no op */
552 return 0;
553}
554
555static int disk_flush(struct dirty_log *log)
556{
557 int r;
558 struct log_c *lc = (struct log_c *) log->context;
559
560 /* only write if the log has changed */
561 if (!lc->touched)
562 return 0;
563
Kevin Corry702ca6f2006-06-26 00:27:28 -0700564 r = write_header(lc);
Jonathan E Brassow01d03a62007-05-09 02:32:57 -0700565 if (r)
566 fail_log_device(lc);
567 else
Linus Torvalds1da177e2005-04-16 15:20:36 -0700568 lc->touched = 0;
569
570 return r;
571}
572
573static void core_mark_region(struct dirty_log *log, region_t region)
574{
575 struct log_c *lc = (struct log_c *) log->context;
576 log_clear_bit(lc, lc->clean_bits, region);
577}
578
579static void core_clear_region(struct dirty_log *log, region_t region)
580{
581 struct log_c *lc = (struct log_c *) log->context;
582 log_set_bit(lc, lc->clean_bits, region);
583}
584
585static int core_get_resync_work(struct dirty_log *log, region_t *region)
586{
587 struct log_c *lc = (struct log_c *) log->context;
588
589 if (lc->sync_search >= lc->region_count)
590 return 0;
591
592 do {
Stefan Bader1113a7e2006-02-02 14:28:07 -0800593 *region = ext2_find_next_zero_bit(
594 (unsigned long *) lc->sync_bits,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700595 lc->region_count,
596 lc->sync_search);
597 lc->sync_search = *region + 1;
598
Darrick J. Wongac81b2e2006-01-06 00:20:11 -0800599 if (*region >= lc->region_count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700600 return 0;
601
602 } while (log_test_bit(lc->recovering_bits, *region));
603
604 log_set_bit(lc, lc->recovering_bits, *region);
605 return 1;
606}
607
Jonathan E Brassowf3ee6b22006-12-08 02:41:11 -0800608static void core_set_region_sync(struct dirty_log *log, region_t region,
609 int in_sync)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700610{
611 struct log_c *lc = (struct log_c *) log->context;
612
613 log_clear_bit(lc, lc->recovering_bits, region);
Jonathan E Brassowf3ee6b22006-12-08 02:41:11 -0800614 if (in_sync) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700615 log_set_bit(lc, lc->sync_bits, region);
616 lc->sync_count++;
Jonathan E Brassowf3ee6b22006-12-08 02:41:11 -0800617 } else if (log_test_bit(lc->sync_bits, region)) {
618 lc->sync_count--;
619 log_clear_bit(lc, lc->sync_bits, region);
620 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700621}
622
623static region_t core_get_sync_count(struct dirty_log *log)
624{
625 struct log_c *lc = (struct log_c *) log->context;
626
627 return lc->sync_count;
628}
629
630#define DMEMIT_SYNC \
631 if (lc->sync != DEFAULTSYNC) \
632 DMEMIT("%ssync ", lc->sync == NOSYNC ? "no" : "")
633
634static int core_status(struct dirty_log *log, status_type_t status,
635 char *result, unsigned int maxlen)
636{
637 int sz = 0;
638 struct log_c *lc = log->context;
639
640 switch(status) {
641 case STATUSTYPE_INFO:
Jonathan E Brassow315dcc22007-05-09 02:32:58 -0700642 DMEMIT("1 %s", log->type->name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700643 break;
644
645 case STATUSTYPE_TABLE:
646 DMEMIT("%s %u %u ", log->type->name,
647 lc->sync == DEFAULTSYNC ? 1 : 2, lc->region_size);
648 DMEMIT_SYNC;
649 }
650
651 return sz;
652}
653
654static int disk_status(struct dirty_log *log, status_type_t status,
655 char *result, unsigned int maxlen)
656{
657 int sz = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700658 struct log_c *lc = log->context;
659
660 switch(status) {
661 case STATUSTYPE_INFO:
Jonathan E Brassow315dcc22007-05-09 02:32:58 -0700662 DMEMIT("3 %s %s %c", log->type->name, lc->log_dev->name,
663 lc->log_dev_failed ? 'D' : 'A');
Linus Torvalds1da177e2005-04-16 15:20:36 -0700664 break;
665
666 case STATUSTYPE_TABLE:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700667 DMEMIT("%s %u %s %u ", log->type->name,
Jonathan E Brassow315dcc22007-05-09 02:32:58 -0700668 lc->sync == DEFAULTSYNC ? 2 : 3, lc->log_dev->name,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700669 lc->region_size);
670 DMEMIT_SYNC;
671 }
672
673 return sz;
674}
675
676static struct dirty_log_type _core_type = {
677 .name = "core",
678 .module = THIS_MODULE,
679 .ctr = core_ctr,
680 .dtr = core_dtr,
Jonathan E Brassow88b20a12006-12-08 02:41:12 -0800681 .resume = core_resume,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700682 .get_region_size = core_get_region_size,
683 .is_clean = core_is_clean,
684 .in_sync = core_in_sync,
685 .flush = core_flush,
686 .mark_region = core_mark_region,
687 .clear_region = core_clear_region,
688 .get_resync_work = core_get_resync_work,
Jonathan E Brassowf3ee6b22006-12-08 02:41:11 -0800689 .set_region_sync = core_set_region_sync,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700690 .get_sync_count = core_get_sync_count,
691 .status = core_status,
692};
693
694static struct dirty_log_type _disk_type = {
695 .name = "disk",
696 .module = THIS_MODULE,
697 .ctr = disk_ctr,
698 .dtr = disk_dtr,
699 .suspend = disk_flush,
700 .resume = disk_resume,
701 .get_region_size = core_get_region_size,
702 .is_clean = core_is_clean,
703 .in_sync = core_in_sync,
704 .flush = disk_flush,
705 .mark_region = core_mark_region,
706 .clear_region = core_clear_region,
707 .get_resync_work = core_get_resync_work,
Jonathan E Brassowf3ee6b22006-12-08 02:41:11 -0800708 .set_region_sync = core_set_region_sync,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700709 .get_sync_count = core_get_sync_count,
710 .status = disk_status,
711};
712
713int __init dm_dirty_log_init(void)
714{
715 int r;
716
717 r = dm_register_dirty_log_type(&_core_type);
718 if (r)
719 DMWARN("couldn't register core log");
720
721 r = dm_register_dirty_log_type(&_disk_type);
722 if (r) {
723 DMWARN("couldn't register disk type");
724 dm_unregister_dirty_log_type(&_core_type);
725 }
726
727 return r;
728}
729
730void dm_dirty_log_exit(void)
731{
732 dm_unregister_dirty_log_type(&_disk_type);
733 dm_unregister_dirty_log_type(&_core_type);
734}
735
736EXPORT_SYMBOL(dm_register_dirty_log_type);
737EXPORT_SYMBOL(dm_unregister_dirty_log_type);
738EXPORT_SYMBOL(dm_create_dirty_log);
739EXPORT_SYMBOL(dm_destroy_dirty_log);