blob: 9fc616c2755ed752a50930e1095df8a7a34303f2 [file] [log] [blame]
Joe Thornberc6b4fcb2013-03-01 22:45:51 +00001/*
2 * Copyright (C) 2012 Red Hat, Inc.
3 *
4 * This file is released under the GPL.
5 */
6
7#include "dm-cache-metadata.h"
8
9#include "persistent-data/dm-array.h"
10#include "persistent-data/dm-bitset.h"
11#include "persistent-data/dm-space-map.h"
12#include "persistent-data/dm-space-map-disk.h"
13#include "persistent-data/dm-transaction-manager.h"
14
15#include <linux/device-mapper.h>
16
17/*----------------------------------------------------------------*/
18
19#define DM_MSG_PREFIX "cache metadata"
20
21#define CACHE_SUPERBLOCK_MAGIC 06142003
22#define CACHE_SUPERBLOCK_LOCATION 0
Joe Thornber53d49812013-10-16 10:59:26 +010023
24/*
25 * defines a range of metadata versions that this module can handle.
26 */
27#define MIN_CACHE_VERSION 1
28#define MAX_CACHE_VERSION 1
29
Joe Thornberc6b4fcb2013-03-01 22:45:51 +000030#define CACHE_METADATA_CACHE_SIZE 64
31
32/*
33 * 3 for btree insert +
34 * 2 for btree lookup used within space map
35 */
36#define CACHE_MAX_CONCURRENT_LOCKS 5
37#define SPACE_MAP_ROOT_SIZE 128
38
39enum superblock_flag_bits {
40 /* for spotting crashes that would invalidate the dirty bitset */
41 CLEAN_SHUTDOWN,
42};
43
44/*
45 * Each mapping from cache block -> origin block carries a set of flags.
46 */
47enum mapping_bits {
48 /*
49 * A valid mapping. Because we're using an array we clear this
50 * flag for an non existant mapping.
51 */
52 M_VALID = 1,
53
54 /*
55 * The data on the cache is different from that on the origin.
56 */
57 M_DIRTY = 2
58};
59
60struct cache_disk_superblock {
61 __le32 csum;
62 __le32 flags;
63 __le64 blocknr;
64
65 __u8 uuid[16];
66 __le64 magic;
67 __le32 version;
68
69 __u8 policy_name[CACHE_POLICY_NAME_SIZE];
70 __le32 policy_hint_size;
71
72 __u8 metadata_space_map_root[SPACE_MAP_ROOT_SIZE];
73 __le64 mapping_root;
74 __le64 hint_root;
75
76 __le64 discard_root;
77 __le64 discard_block_size;
78 __le64 discard_nr_blocks;
79
80 __le32 data_block_size;
81 __le32 metadata_block_size;
82 __le32 cache_blocks;
83
84 __le32 compat_flags;
85 __le32 compat_ro_flags;
86 __le32 incompat_flags;
87
88 __le32 read_hits;
89 __le32 read_misses;
90 __le32 write_hits;
91 __le32 write_misses;
Mike Snitzer4e7f5062013-03-20 17:21:27 +000092
93 __le32 policy_version[CACHE_POLICY_VERSION_SIZE];
Joe Thornberc6b4fcb2013-03-01 22:45:51 +000094} __packed;
95
96struct dm_cache_metadata {
97 struct block_device *bdev;
98 struct dm_block_manager *bm;
99 struct dm_space_map *metadata_sm;
100 struct dm_transaction_manager *tm;
101
102 struct dm_array_info info;
103 struct dm_array_info hint_info;
104 struct dm_disk_bitset discard_info;
105
106 struct rw_semaphore root_lock;
107 dm_block_t root;
108 dm_block_t hint_root;
109 dm_block_t discard_root;
110
111 sector_t discard_block_size;
Joe Thornber1bad9bc2014-11-07 14:47:07 +0000112 dm_dblock_t discard_nr_blocks;
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000113
114 sector_t data_block_size;
115 dm_cblock_t cache_blocks;
116 bool changed:1;
117 bool clean_when_opened:1;
118
119 char policy_name[CACHE_POLICY_NAME_SIZE];
Mike Snitzer4e7f5062013-03-20 17:21:27 +0000120 unsigned policy_version[CACHE_POLICY_VERSION_SIZE];
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000121 size_t policy_hint_size;
122 struct dm_cache_statistics stats;
Joe Thornber5a320832014-03-27 14:13:23 +0000123
124 /*
125 * Reading the space map root can fail, so we read it into this
126 * buffer before the superblock is locked and updated.
127 */
128 __u8 metadata_space_map_root[SPACE_MAP_ROOT_SIZE];
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000129};
130
131/*-------------------------------------------------------------------
132 * superblock validator
133 *-----------------------------------------------------------------*/
134
135#define SUPERBLOCK_CSUM_XOR 9031977
136
137static void sb_prepare_for_write(struct dm_block_validator *v,
138 struct dm_block *b,
139 size_t sb_block_size)
140{
141 struct cache_disk_superblock *disk_super = dm_block_data(b);
142
143 disk_super->blocknr = cpu_to_le64(dm_block_location(b));
144 disk_super->csum = cpu_to_le32(dm_bm_checksum(&disk_super->flags,
145 sb_block_size - sizeof(__le32),
146 SUPERBLOCK_CSUM_XOR));
147}
148
Joe Thornber53d49812013-10-16 10:59:26 +0100149static int check_metadata_version(struct cache_disk_superblock *disk_super)
150{
151 uint32_t metadata_version = le32_to_cpu(disk_super->version);
152 if (metadata_version < MIN_CACHE_VERSION || metadata_version > MAX_CACHE_VERSION) {
153 DMERR("Cache metadata version %u found, but only versions between %u and %u supported.",
154 metadata_version, MIN_CACHE_VERSION, MAX_CACHE_VERSION);
155 return -EINVAL;
156 }
157
158 return 0;
159}
160
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000161static int sb_check(struct dm_block_validator *v,
162 struct dm_block *b,
163 size_t sb_block_size)
164{
165 struct cache_disk_superblock *disk_super = dm_block_data(b);
166 __le32 csum_le;
167
168 if (dm_block_location(b) != le64_to_cpu(disk_super->blocknr)) {
169 DMERR("sb_check failed: blocknr %llu: wanted %llu",
170 le64_to_cpu(disk_super->blocknr),
171 (unsigned long long)dm_block_location(b));
172 return -ENOTBLK;
173 }
174
175 if (le64_to_cpu(disk_super->magic) != CACHE_SUPERBLOCK_MAGIC) {
176 DMERR("sb_check failed: magic %llu: wanted %llu",
177 le64_to_cpu(disk_super->magic),
178 (unsigned long long)CACHE_SUPERBLOCK_MAGIC);
179 return -EILSEQ;
180 }
181
182 csum_le = cpu_to_le32(dm_bm_checksum(&disk_super->flags,
183 sb_block_size - sizeof(__le32),
184 SUPERBLOCK_CSUM_XOR));
185 if (csum_le != disk_super->csum) {
186 DMERR("sb_check failed: csum %u: wanted %u",
187 le32_to_cpu(csum_le), le32_to_cpu(disk_super->csum));
188 return -EILSEQ;
189 }
190
Joe Thornber53d49812013-10-16 10:59:26 +0100191 return check_metadata_version(disk_super);
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000192}
193
194static struct dm_block_validator sb_validator = {
195 .name = "superblock",
196 .prepare_for_write = sb_prepare_for_write,
197 .check = sb_check
198};
199
200/*----------------------------------------------------------------*/
201
202static int superblock_read_lock(struct dm_cache_metadata *cmd,
203 struct dm_block **sblock)
204{
205 return dm_bm_read_lock(cmd->bm, CACHE_SUPERBLOCK_LOCATION,
206 &sb_validator, sblock);
207}
208
209static int superblock_lock_zero(struct dm_cache_metadata *cmd,
210 struct dm_block **sblock)
211{
212 return dm_bm_write_lock_zero(cmd->bm, CACHE_SUPERBLOCK_LOCATION,
213 &sb_validator, sblock);
214}
215
216static int superblock_lock(struct dm_cache_metadata *cmd,
217 struct dm_block **sblock)
218{
219 return dm_bm_write_lock(cmd->bm, CACHE_SUPERBLOCK_LOCATION,
220 &sb_validator, sblock);
221}
222
223/*----------------------------------------------------------------*/
224
Joe Thornberdd8b0c22013-10-24 14:10:28 -0400225static int __superblock_all_zeroes(struct dm_block_manager *bm, bool *result)
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000226{
227 int r;
228 unsigned i;
229 struct dm_block *b;
230 __le64 *data_le, zero = cpu_to_le64(0);
231 unsigned sb_block_size = dm_bm_block_size(bm) / sizeof(__le64);
232
233 /*
234 * We can't use a validator here - it may be all zeroes.
235 */
236 r = dm_bm_read_lock(bm, CACHE_SUPERBLOCK_LOCATION, NULL, &b);
237 if (r)
238 return r;
239
240 data_le = dm_block_data(b);
Joe Thornberdd8b0c22013-10-24 14:10:28 -0400241 *result = true;
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000242 for (i = 0; i < sb_block_size; i++) {
243 if (data_le[i] != zero) {
Joe Thornberdd8b0c22013-10-24 14:10:28 -0400244 *result = false;
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000245 break;
246 }
247 }
248
249 return dm_bm_unlock(b);
250}
251
252static void __setup_mapping_info(struct dm_cache_metadata *cmd)
253{
254 struct dm_btree_value_type vt;
255
256 vt.context = NULL;
257 vt.size = sizeof(__le64);
258 vt.inc = NULL;
259 vt.dec = NULL;
260 vt.equal = NULL;
261 dm_array_info_init(&cmd->info, cmd->tm, &vt);
262
263 if (cmd->policy_hint_size) {
264 vt.size = sizeof(__le32);
265 dm_array_info_init(&cmd->hint_info, cmd->tm, &vt);
266 }
267}
268
Joe Thornber5a320832014-03-27 14:13:23 +0000269static int __save_sm_root(struct dm_cache_metadata *cmd)
270{
271 int r;
272 size_t metadata_len;
273
274 r = dm_sm_root_size(cmd->metadata_sm, &metadata_len);
275 if (r < 0)
276 return r;
277
278 return dm_sm_copy_root(cmd->metadata_sm, &cmd->metadata_space_map_root,
279 metadata_len);
280}
281
282static void __copy_sm_root(struct dm_cache_metadata *cmd,
283 struct cache_disk_superblock *disk_super)
284{
285 memcpy(&disk_super->metadata_space_map_root,
286 &cmd->metadata_space_map_root,
287 sizeof(cmd->metadata_space_map_root));
288}
289
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000290static int __write_initial_superblock(struct dm_cache_metadata *cmd)
291{
292 int r;
293 struct dm_block *sblock;
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000294 struct cache_disk_superblock *disk_super;
295 sector_t bdev_size = i_size_read(cmd->bdev->bd_inode) >> SECTOR_SHIFT;
296
297 /* FIXME: see if we can lose the max sectors limit */
298 if (bdev_size > DM_CACHE_METADATA_MAX_SECTORS)
299 bdev_size = DM_CACHE_METADATA_MAX_SECTORS;
300
Joe Thornber5a320832014-03-27 14:13:23 +0000301 r = dm_tm_pre_commit(cmd->tm);
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000302 if (r < 0)
303 return r;
304
Joe Thornber5a320832014-03-27 14:13:23 +0000305 /*
306 * dm_sm_copy_root() can fail. So we need to do it before we start
307 * updating the superblock.
308 */
309 r = __save_sm_root(cmd);
310 if (r)
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000311 return r;
312
313 r = superblock_lock_zero(cmd, &sblock);
314 if (r)
315 return r;
316
317 disk_super = dm_block_data(sblock);
318 disk_super->flags = 0;
319 memset(disk_super->uuid, 0, sizeof(disk_super->uuid));
320 disk_super->magic = cpu_to_le64(CACHE_SUPERBLOCK_MAGIC);
Joe Thornber53d49812013-10-16 10:59:26 +0100321 disk_super->version = cpu_to_le32(MAX_CACHE_VERSION);
Mike Snitzer4e7f5062013-03-20 17:21:27 +0000322 memset(disk_super->policy_name, 0, sizeof(disk_super->policy_name));
323 memset(disk_super->policy_version, 0, sizeof(disk_super->policy_version));
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000324 disk_super->policy_hint_size = 0;
325
Joe Thornber5a320832014-03-27 14:13:23 +0000326 __copy_sm_root(cmd, disk_super);
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000327
328 disk_super->mapping_root = cpu_to_le64(cmd->root);
329 disk_super->hint_root = cpu_to_le64(cmd->hint_root);
330 disk_super->discard_root = cpu_to_le64(cmd->discard_root);
331 disk_super->discard_block_size = cpu_to_le64(cmd->discard_block_size);
Joe Thornber1bad9bc2014-11-07 14:47:07 +0000332 disk_super->discard_nr_blocks = cpu_to_le64(from_dblock(cmd->discard_nr_blocks));
Mike Snitzer895b47d2014-07-14 15:37:18 -0400333 disk_super->metadata_block_size = cpu_to_le32(DM_CACHE_METADATA_BLOCK_SIZE);
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000334 disk_super->data_block_size = cpu_to_le32(cmd->data_block_size);
335 disk_super->cache_blocks = cpu_to_le32(0);
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000336
337 disk_super->read_hits = cpu_to_le32(0);
338 disk_super->read_misses = cpu_to_le32(0);
339 disk_super->write_hits = cpu_to_le32(0);
340 disk_super->write_misses = cpu_to_le32(0);
341
342 return dm_tm_commit(cmd->tm, sblock);
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000343}
344
345static int __format_metadata(struct dm_cache_metadata *cmd)
346{
347 int r;
348
349 r = dm_tm_create_with_sm(cmd->bm, CACHE_SUPERBLOCK_LOCATION,
350 &cmd->tm, &cmd->metadata_sm);
351 if (r < 0) {
352 DMERR("tm_create_with_sm failed");
353 return r;
354 }
355
356 __setup_mapping_info(cmd);
357
358 r = dm_array_empty(&cmd->info, &cmd->root);
359 if (r < 0)
360 goto bad;
361
362 dm_disk_bitset_init(cmd->tm, &cmd->discard_info);
363
364 r = dm_bitset_empty(&cmd->discard_info, &cmd->discard_root);
365 if (r < 0)
366 goto bad;
367
368 cmd->discard_block_size = 0;
369 cmd->discard_nr_blocks = 0;
370
371 r = __write_initial_superblock(cmd);
372 if (r)
373 goto bad;
374
375 cmd->clean_when_opened = true;
376 return 0;
377
378bad:
379 dm_tm_destroy(cmd->tm);
380 dm_sm_destroy(cmd->metadata_sm);
381
382 return r;
383}
384
385static int __check_incompat_features(struct cache_disk_superblock *disk_super,
386 struct dm_cache_metadata *cmd)
387{
388 uint32_t features;
389
390 features = le32_to_cpu(disk_super->incompat_flags) & ~DM_CACHE_FEATURE_INCOMPAT_SUPP;
391 if (features) {
392 DMERR("could not access metadata due to unsupported optional features (%lx).",
393 (unsigned long)features);
394 return -EINVAL;
395 }
396
397 /*
398 * Check for read-only metadata to skip the following RDWR checks.
399 */
400 if (get_disk_ro(cmd->bdev->bd_disk))
401 return 0;
402
403 features = le32_to_cpu(disk_super->compat_ro_flags) & ~DM_CACHE_FEATURE_COMPAT_RO_SUPP;
404 if (features) {
405 DMERR("could not access metadata RDWR due to unsupported optional features (%lx).",
406 (unsigned long)features);
407 return -EINVAL;
408 }
409
410 return 0;
411}
412
413static int __open_metadata(struct dm_cache_metadata *cmd)
414{
415 int r;
416 struct dm_block *sblock;
417 struct cache_disk_superblock *disk_super;
418 unsigned long sb_flags;
419
420 r = superblock_read_lock(cmd, &sblock);
421 if (r < 0) {
422 DMERR("couldn't read lock superblock");
423 return r;
424 }
425
426 disk_super = dm_block_data(sblock);
427
Mike Snitzer048e5a02014-07-14 16:59:39 -0400428 /* Verify the data block size hasn't changed */
429 if (le32_to_cpu(disk_super->data_block_size) != cmd->data_block_size) {
430 DMERR("changing the data block size (from %u to %llu) is not supported",
431 le32_to_cpu(disk_super->data_block_size),
432 (unsigned long long)cmd->data_block_size);
433 r = -EINVAL;
434 goto bad;
435 }
436
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000437 r = __check_incompat_features(disk_super, cmd);
438 if (r < 0)
439 goto bad;
440
441 r = dm_tm_open_with_sm(cmd->bm, CACHE_SUPERBLOCK_LOCATION,
442 disk_super->metadata_space_map_root,
443 sizeof(disk_super->metadata_space_map_root),
444 &cmd->tm, &cmd->metadata_sm);
445 if (r < 0) {
446 DMERR("tm_open_with_sm failed");
447 goto bad;
448 }
449
450 __setup_mapping_info(cmd);
451 dm_disk_bitset_init(cmd->tm, &cmd->discard_info);
452 sb_flags = le32_to_cpu(disk_super->flags);
453 cmd->clean_when_opened = test_bit(CLEAN_SHUTDOWN, &sb_flags);
454 return dm_bm_unlock(sblock);
455
456bad:
457 dm_bm_unlock(sblock);
458 return r;
459}
460
461static int __open_or_format_metadata(struct dm_cache_metadata *cmd,
462 bool format_device)
463{
Joe Thornberdd8b0c22013-10-24 14:10:28 -0400464 int r;
465 bool unformatted = false;
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000466
467 r = __superblock_all_zeroes(cmd->bm, &unformatted);
468 if (r)
469 return r;
470
471 if (unformatted)
472 return format_device ? __format_metadata(cmd) : -EPERM;
473
474 return __open_metadata(cmd);
475}
476
477static int __create_persistent_data_objects(struct dm_cache_metadata *cmd,
478 bool may_format_device)
479{
480 int r;
Mike Snitzer895b47d2014-07-14 15:37:18 -0400481 cmd->bm = dm_block_manager_create(cmd->bdev, DM_CACHE_METADATA_BLOCK_SIZE << SECTOR_SHIFT,
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000482 CACHE_METADATA_CACHE_SIZE,
483 CACHE_MAX_CONCURRENT_LOCKS);
484 if (IS_ERR(cmd->bm)) {
485 DMERR("could not create block manager");
486 return PTR_ERR(cmd->bm);
487 }
488
489 r = __open_or_format_metadata(cmd, may_format_device);
490 if (r)
491 dm_block_manager_destroy(cmd->bm);
492
493 return r;
494}
495
496static void __destroy_persistent_data_objects(struct dm_cache_metadata *cmd)
497{
498 dm_sm_destroy(cmd->metadata_sm);
499 dm_tm_destroy(cmd->tm);
500 dm_block_manager_destroy(cmd->bm);
501}
502
503typedef unsigned long (*flags_mutator)(unsigned long);
504
505static void update_flags(struct cache_disk_superblock *disk_super,
506 flags_mutator mutator)
507{
508 uint32_t sb_flags = mutator(le32_to_cpu(disk_super->flags));
509 disk_super->flags = cpu_to_le32(sb_flags);
510}
511
512static unsigned long set_clean_shutdown(unsigned long flags)
513{
514 set_bit(CLEAN_SHUTDOWN, &flags);
515 return flags;
516}
517
518static unsigned long clear_clean_shutdown(unsigned long flags)
519{
520 clear_bit(CLEAN_SHUTDOWN, &flags);
521 return flags;
522}
523
524static void read_superblock_fields(struct dm_cache_metadata *cmd,
525 struct cache_disk_superblock *disk_super)
526{
527 cmd->root = le64_to_cpu(disk_super->mapping_root);
528 cmd->hint_root = le64_to_cpu(disk_super->hint_root);
529 cmd->discard_root = le64_to_cpu(disk_super->discard_root);
530 cmd->discard_block_size = le64_to_cpu(disk_super->discard_block_size);
Joe Thornber1bad9bc2014-11-07 14:47:07 +0000531 cmd->discard_nr_blocks = to_dblock(le64_to_cpu(disk_super->discard_nr_blocks));
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000532 cmd->data_block_size = le32_to_cpu(disk_super->data_block_size);
533 cmd->cache_blocks = to_cblock(le32_to_cpu(disk_super->cache_blocks));
534 strncpy(cmd->policy_name, disk_super->policy_name, sizeof(cmd->policy_name));
Mike Snitzer4e7f5062013-03-20 17:21:27 +0000535 cmd->policy_version[0] = le32_to_cpu(disk_super->policy_version[0]);
536 cmd->policy_version[1] = le32_to_cpu(disk_super->policy_version[1]);
537 cmd->policy_version[2] = le32_to_cpu(disk_super->policy_version[2]);
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000538 cmd->policy_hint_size = le32_to_cpu(disk_super->policy_hint_size);
539
540 cmd->stats.read_hits = le32_to_cpu(disk_super->read_hits);
541 cmd->stats.read_misses = le32_to_cpu(disk_super->read_misses);
542 cmd->stats.write_hits = le32_to_cpu(disk_super->write_hits);
543 cmd->stats.write_misses = le32_to_cpu(disk_super->write_misses);
544
545 cmd->changed = false;
546}
547
548/*
549 * The mutator updates the superblock flags.
550 */
551static int __begin_transaction_flags(struct dm_cache_metadata *cmd,
552 flags_mutator mutator)
553{
554 int r;
555 struct cache_disk_superblock *disk_super;
556 struct dm_block *sblock;
557
558 r = superblock_lock(cmd, &sblock);
559 if (r)
560 return r;
561
562 disk_super = dm_block_data(sblock);
563 update_flags(disk_super, mutator);
564 read_superblock_fields(cmd, disk_super);
Joe Thornbera9d45392014-03-27 14:13:20 +0000565 dm_bm_unlock(sblock);
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000566
Joe Thornbera9d45392014-03-27 14:13:20 +0000567 return dm_bm_flush(cmd->bm);
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000568}
569
570static int __begin_transaction(struct dm_cache_metadata *cmd)
571{
572 int r;
573 struct cache_disk_superblock *disk_super;
574 struct dm_block *sblock;
575
576 /*
577 * We re-read the superblock every time. Shouldn't need to do this
578 * really.
579 */
580 r = superblock_read_lock(cmd, &sblock);
581 if (r)
582 return r;
583
584 disk_super = dm_block_data(sblock);
585 read_superblock_fields(cmd, disk_super);
586 dm_bm_unlock(sblock);
587
588 return 0;
589}
590
591static int __commit_transaction(struct dm_cache_metadata *cmd,
592 flags_mutator mutator)
593{
594 int r;
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000595 struct cache_disk_superblock *disk_super;
596 struct dm_block *sblock;
597
598 /*
599 * We need to know if the cache_disk_superblock exceeds a 512-byte sector.
600 */
601 BUILD_BUG_ON(sizeof(struct cache_disk_superblock) > 512);
602
603 r = dm_bitset_flush(&cmd->discard_info, cmd->discard_root,
604 &cmd->discard_root);
605 if (r)
606 return r;
607
608 r = dm_tm_pre_commit(cmd->tm);
609 if (r < 0)
610 return r;
611
Joe Thornber5a320832014-03-27 14:13:23 +0000612 r = __save_sm_root(cmd);
613 if (r)
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000614 return r;
615
616 r = superblock_lock(cmd, &sblock);
617 if (r)
618 return r;
619
620 disk_super = dm_block_data(sblock);
621
622 if (mutator)
623 update_flags(disk_super, mutator);
624
625 disk_super->mapping_root = cpu_to_le64(cmd->root);
626 disk_super->hint_root = cpu_to_le64(cmd->hint_root);
627 disk_super->discard_root = cpu_to_le64(cmd->discard_root);
628 disk_super->discard_block_size = cpu_to_le64(cmd->discard_block_size);
Joe Thornber1bad9bc2014-11-07 14:47:07 +0000629 disk_super->discard_nr_blocks = cpu_to_le64(from_dblock(cmd->discard_nr_blocks));
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000630 disk_super->cache_blocks = cpu_to_le32(from_cblock(cmd->cache_blocks));
631 strncpy(disk_super->policy_name, cmd->policy_name, sizeof(disk_super->policy_name));
Mike Snitzer4e7f5062013-03-20 17:21:27 +0000632 disk_super->policy_version[0] = cpu_to_le32(cmd->policy_version[0]);
633 disk_super->policy_version[1] = cpu_to_le32(cmd->policy_version[1]);
634 disk_super->policy_version[2] = cpu_to_le32(cmd->policy_version[2]);
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000635
636 disk_super->read_hits = cpu_to_le32(cmd->stats.read_hits);
637 disk_super->read_misses = cpu_to_le32(cmd->stats.read_misses);
638 disk_super->write_hits = cpu_to_le32(cmd->stats.write_hits);
639 disk_super->write_misses = cpu_to_le32(cmd->stats.write_misses);
Joe Thornber5a320832014-03-27 14:13:23 +0000640 __copy_sm_root(cmd, disk_super);
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000641
642 return dm_tm_commit(cmd->tm, sblock);
643}
644
645/*----------------------------------------------------------------*/
646
647/*
648 * The mappings are held in a dm-array that has 64-bit values stored in
649 * little-endian format. The index is the cblock, the high 48bits of the
650 * value are the oblock and the low 16 bit the flags.
651 */
652#define FLAGS_MASK ((1 << 16) - 1)
653
654static __le64 pack_value(dm_oblock_t block, unsigned flags)
655{
656 uint64_t value = from_oblock(block);
657 value <<= 16;
658 value = value | (flags & FLAGS_MASK);
659 return cpu_to_le64(value);
660}
661
662static void unpack_value(__le64 value_le, dm_oblock_t *block, unsigned *flags)
663{
664 uint64_t value = le64_to_cpu(value_le);
665 uint64_t b = value >> 16;
666 *block = to_oblock(b);
667 *flags = value & FLAGS_MASK;
668}
669
670/*----------------------------------------------------------------*/
671
672struct dm_cache_metadata *dm_cache_metadata_open(struct block_device *bdev,
673 sector_t data_block_size,
674 bool may_format_device,
675 size_t policy_hint_size)
676{
677 int r;
678 struct dm_cache_metadata *cmd;
679
680 cmd = kzalloc(sizeof(*cmd), GFP_KERNEL);
681 if (!cmd) {
682 DMERR("could not allocate metadata struct");
683 return NULL;
684 }
685
686 init_rwsem(&cmd->root_lock);
687 cmd->bdev = bdev;
688 cmd->data_block_size = data_block_size;
689 cmd->cache_blocks = 0;
690 cmd->policy_hint_size = policy_hint_size;
691 cmd->changed = true;
692
693 r = __create_persistent_data_objects(cmd, may_format_device);
694 if (r) {
695 kfree(cmd);
696 return ERR_PTR(r);
697 }
698
699 r = __begin_transaction_flags(cmd, clear_clean_shutdown);
700 if (r < 0) {
701 dm_cache_metadata_close(cmd);
702 return ERR_PTR(r);
703 }
704
705 return cmd;
706}
707
708void dm_cache_metadata_close(struct dm_cache_metadata *cmd)
709{
710 __destroy_persistent_data_objects(cmd);
711 kfree(cmd);
712}
713
Joe Thornberf494a9c2013-10-31 13:55:49 -0400714/*
715 * Checks that the given cache block is either unmapped or clean.
716 */
717static int block_unmapped_or_clean(struct dm_cache_metadata *cmd, dm_cblock_t b,
718 bool *result)
719{
720 int r;
721 __le64 value;
722 dm_oblock_t ob;
723 unsigned flags;
724
725 r = dm_array_get_value(&cmd->info, cmd->root, from_cblock(b), &value);
726 if (r) {
727 DMERR("block_unmapped_or_clean failed");
728 return r;
729 }
730
731 unpack_value(value, &ob, &flags);
732 *result = !((flags & M_VALID) && (flags & M_DIRTY));
733
734 return 0;
735}
736
737static int blocks_are_unmapped_or_clean(struct dm_cache_metadata *cmd,
738 dm_cblock_t begin, dm_cblock_t end,
739 bool *result)
740{
741 int r;
742 *result = true;
743
744 while (begin != end) {
745 r = block_unmapped_or_clean(cmd, begin, result);
746 if (r)
747 return r;
748
749 if (!*result) {
750 DMERR("cache block %llu is dirty",
751 (unsigned long long) from_cblock(begin));
752 return 0;
753 }
754
755 begin = to_cblock(from_cblock(begin) + 1);
756 }
757
758 return 0;
759}
760
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000761int dm_cache_resize(struct dm_cache_metadata *cmd, dm_cblock_t new_cache_size)
762{
763 int r;
Joe Thornberf494a9c2013-10-31 13:55:49 -0400764 bool clean;
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000765 __le64 null_mapping = pack_value(0, 0);
766
767 down_write(&cmd->root_lock);
768 __dm_bless_for_disk(&null_mapping);
Joe Thornberf494a9c2013-10-31 13:55:49 -0400769
770 if (from_cblock(new_cache_size) < from_cblock(cmd->cache_blocks)) {
771 r = blocks_are_unmapped_or_clean(cmd, new_cache_size, cmd->cache_blocks, &clean);
772 if (r) {
773 __dm_unbless_for_disk(&null_mapping);
774 goto out;
775 }
776
777 if (!clean) {
778 DMERR("unable to shrink cache due to dirty blocks");
779 r = -EINVAL;
780 __dm_unbless_for_disk(&null_mapping);
781 goto out;
782 }
783 }
784
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000785 r = dm_array_resize(&cmd->info, cmd->root, from_cblock(cmd->cache_blocks),
786 from_cblock(new_cache_size),
787 &null_mapping, &cmd->root);
788 if (!r)
789 cmd->cache_blocks = new_cache_size;
790 cmd->changed = true;
Joe Thornberf494a9c2013-10-31 13:55:49 -0400791
792out:
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000793 up_write(&cmd->root_lock);
794
795 return r;
796}
797
798int dm_cache_discard_bitset_resize(struct dm_cache_metadata *cmd,
799 sector_t discard_block_size,
Joe Thornber1bad9bc2014-11-07 14:47:07 +0000800 dm_dblock_t new_nr_entries)
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000801{
802 int r;
803
804 down_write(&cmd->root_lock);
805 r = dm_bitset_resize(&cmd->discard_info,
806 cmd->discard_root,
Joe Thornber1bad9bc2014-11-07 14:47:07 +0000807 from_dblock(cmd->discard_nr_blocks),
808 from_dblock(new_nr_entries),
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000809 false, &cmd->discard_root);
810 if (!r) {
811 cmd->discard_block_size = discard_block_size;
812 cmd->discard_nr_blocks = new_nr_entries;
813 }
814
815 cmd->changed = true;
816 up_write(&cmd->root_lock);
817
818 return r;
819}
820
Joe Thornber1bad9bc2014-11-07 14:47:07 +0000821static int __set_discard(struct dm_cache_metadata *cmd, dm_dblock_t b)
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000822{
823 return dm_bitset_set_bit(&cmd->discard_info, cmd->discard_root,
Joe Thornber1bad9bc2014-11-07 14:47:07 +0000824 from_dblock(b), &cmd->discard_root);
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000825}
826
Joe Thornber1bad9bc2014-11-07 14:47:07 +0000827static int __clear_discard(struct dm_cache_metadata *cmd, dm_dblock_t b)
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000828{
829 return dm_bitset_clear_bit(&cmd->discard_info, cmd->discard_root,
Joe Thornber1bad9bc2014-11-07 14:47:07 +0000830 from_dblock(b), &cmd->discard_root);
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000831}
832
Joe Thornber1bad9bc2014-11-07 14:47:07 +0000833static int __is_discarded(struct dm_cache_metadata *cmd, dm_dblock_t b,
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000834 bool *is_discarded)
835{
836 return dm_bitset_test_bit(&cmd->discard_info, cmd->discard_root,
Joe Thornber1bad9bc2014-11-07 14:47:07 +0000837 from_dblock(b), &cmd->discard_root,
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000838 is_discarded);
839}
840
841static int __discard(struct dm_cache_metadata *cmd,
Joe Thornber1bad9bc2014-11-07 14:47:07 +0000842 dm_dblock_t dblock, bool discard)
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000843{
844 int r;
845
846 r = (discard ? __set_discard : __clear_discard)(cmd, dblock);
847 if (r)
848 return r;
849
850 cmd->changed = true;
851 return 0;
852}
853
854int dm_cache_set_discard(struct dm_cache_metadata *cmd,
Joe Thornber1bad9bc2014-11-07 14:47:07 +0000855 dm_dblock_t dblock, bool discard)
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000856{
857 int r;
858
859 down_write(&cmd->root_lock);
860 r = __discard(cmd, dblock, discard);
861 up_write(&cmd->root_lock);
862
863 return r;
864}
865
866static int __load_discards(struct dm_cache_metadata *cmd,
867 load_discard_fn fn, void *context)
868{
869 int r = 0;
870 dm_block_t b;
871 bool discard;
872
Joe Thornber1bad9bc2014-11-07 14:47:07 +0000873 for (b = 0; b < from_dblock(cmd->discard_nr_blocks); b++) {
874 dm_dblock_t dblock = to_dblock(b);
Joe Thornberc6b4fcb2013-03-01 22:45:51 +0000875
876 if (cmd->clean_when_opened) {
877 r = __is_discarded(cmd, dblock, &discard);
878 if (r)
879 return r;
880 } else
881 discard = false;
882
883 r = fn(context, cmd->discard_block_size, dblock, discard);
884 if (r)
885 break;
886 }
887
888 return r;
889}
890
891int dm_cache_load_discards(struct dm_cache_metadata *cmd,
892 load_discard_fn fn, void *context)
893{
894 int r;
895
896 down_read(&cmd->root_lock);
897 r = __load_discards(cmd, fn, context);
898 up_read(&cmd->root_lock);
899
900 return r;
901}
902
903dm_cblock_t dm_cache_size(struct dm_cache_metadata *cmd)
904{
905 dm_cblock_t r;
906
907 down_read(&cmd->root_lock);
908 r = cmd->cache_blocks;
909 up_read(&cmd->root_lock);
910
911 return r;
912}
913
914static int __remove(struct dm_cache_metadata *cmd, dm_cblock_t cblock)
915{
916 int r;
917 __le64 value = pack_value(0, 0);
918
919 __dm_bless_for_disk(&value);
920 r = dm_array_set_value(&cmd->info, cmd->root, from_cblock(cblock),
921 &value, &cmd->root);
922 if (r)
923 return r;
924
925 cmd->changed = true;
926 return 0;
927}
928
929int dm_cache_remove_mapping(struct dm_cache_metadata *cmd, dm_cblock_t cblock)
930{
931 int r;
932
933 down_write(&cmd->root_lock);
934 r = __remove(cmd, cblock);
935 up_write(&cmd->root_lock);
936
937 return r;
938}
939
940static int __insert(struct dm_cache_metadata *cmd,
941 dm_cblock_t cblock, dm_oblock_t oblock)
942{
943 int r;
944 __le64 value = pack_value(oblock, M_VALID);
945 __dm_bless_for_disk(&value);
946
947 r = dm_array_set_value(&cmd->info, cmd->root, from_cblock(cblock),
948 &value, &cmd->root);
949 if (r)
950 return r;
951
952 cmd->changed = true;
953 return 0;
954}
955
956int dm_cache_insert_mapping(struct dm_cache_metadata *cmd,
957 dm_cblock_t cblock, dm_oblock_t oblock)
958{
959 int r;
960
961 down_write(&cmd->root_lock);
962 r = __insert(cmd, cblock, oblock);
963 up_write(&cmd->root_lock);
964
965 return r;
966}
967
968struct thunk {
969 load_mapping_fn fn;
970 void *context;
971
972 struct dm_cache_metadata *cmd;
973 bool respect_dirty_flags;
974 bool hints_valid;
975};
976
Mike Snitzerea2dd8c2013-03-20 17:21:28 +0000977static bool policy_unchanged(struct dm_cache_metadata *cmd,
978 struct dm_cache_policy *policy)
979{
980 const char *policy_name = dm_cache_policy_get_name(policy);
981 const unsigned *policy_version = dm_cache_policy_get_version(policy);
982 size_t policy_hint_size = dm_cache_policy_get_hint_size(policy);
983
984 /*
985 * Ensure policy names match.
986 */
987 if (strncmp(cmd->policy_name, policy_name, sizeof(cmd->policy_name)))
988 return false;
989
990 /*
991 * Ensure policy major versions match.
992 */
993 if (cmd->policy_version[0] != policy_version[0])
994 return false;
995
996 /*
997 * Ensure policy hint sizes match.
998 */
999 if (cmd->policy_hint_size != policy_hint_size)
1000 return false;
1001
1002 return true;
1003}
1004
Joe Thornberc6b4fcb2013-03-01 22:45:51 +00001005static bool hints_array_initialized(struct dm_cache_metadata *cmd)
1006{
1007 return cmd->hint_root && cmd->policy_hint_size;
1008}
1009
1010static bool hints_array_available(struct dm_cache_metadata *cmd,
Mike Snitzerea2dd8c2013-03-20 17:21:28 +00001011 struct dm_cache_policy *policy)
Joe Thornberc6b4fcb2013-03-01 22:45:51 +00001012{
Mike Snitzerea2dd8c2013-03-20 17:21:28 +00001013 return cmd->clean_when_opened && policy_unchanged(cmd, policy) &&
Joe Thornberc6b4fcb2013-03-01 22:45:51 +00001014 hints_array_initialized(cmd);
1015}
1016
1017static int __load_mapping(void *context, uint64_t cblock, void *leaf)
1018{
1019 int r = 0;
1020 bool dirty;
1021 __le64 value;
1022 __le32 hint_value = 0;
1023 dm_oblock_t oblock;
1024 unsigned flags;
1025 struct thunk *thunk = context;
1026 struct dm_cache_metadata *cmd = thunk->cmd;
1027
1028 memcpy(&value, leaf, sizeof(value));
1029 unpack_value(value, &oblock, &flags);
1030
1031 if (flags & M_VALID) {
1032 if (thunk->hints_valid) {
1033 r = dm_array_get_value(&cmd->hint_info, cmd->hint_root,
1034 cblock, &hint_value);
1035 if (r && r != -ENODATA)
1036 return r;
1037 }
1038
1039 dirty = thunk->respect_dirty_flags ? (flags & M_DIRTY) : true;
1040 r = thunk->fn(thunk->context, oblock, to_cblock(cblock),
1041 dirty, le32_to_cpu(hint_value), thunk->hints_valid);
1042 }
1043
1044 return r;
1045}
1046
Mike Snitzerea2dd8c2013-03-20 17:21:28 +00001047static int __load_mappings(struct dm_cache_metadata *cmd,
1048 struct dm_cache_policy *policy,
Joe Thornberc6b4fcb2013-03-01 22:45:51 +00001049 load_mapping_fn fn, void *context)
1050{
1051 struct thunk thunk;
1052
1053 thunk.fn = fn;
1054 thunk.context = context;
1055
1056 thunk.cmd = cmd;
1057 thunk.respect_dirty_flags = cmd->clean_when_opened;
Mike Snitzerea2dd8c2013-03-20 17:21:28 +00001058 thunk.hints_valid = hints_array_available(cmd, policy);
Joe Thornberc6b4fcb2013-03-01 22:45:51 +00001059
1060 return dm_array_walk(&cmd->info, cmd->root, __load_mapping, &thunk);
1061}
1062
Mike Snitzerea2dd8c2013-03-20 17:21:28 +00001063int dm_cache_load_mappings(struct dm_cache_metadata *cmd,
1064 struct dm_cache_policy *policy,
Joe Thornberc6b4fcb2013-03-01 22:45:51 +00001065 load_mapping_fn fn, void *context)
1066{
1067 int r;
1068
1069 down_read(&cmd->root_lock);
Mike Snitzerea2dd8c2013-03-20 17:21:28 +00001070 r = __load_mappings(cmd, policy, fn, context);
Joe Thornberc6b4fcb2013-03-01 22:45:51 +00001071 up_read(&cmd->root_lock);
1072
1073 return r;
1074}
1075
1076static int __dump_mapping(void *context, uint64_t cblock, void *leaf)
1077{
1078 int r = 0;
1079 __le64 value;
1080 dm_oblock_t oblock;
1081 unsigned flags;
1082
1083 memcpy(&value, leaf, sizeof(value));
1084 unpack_value(value, &oblock, &flags);
1085
1086 return r;
1087}
1088
1089static int __dump_mappings(struct dm_cache_metadata *cmd)
1090{
1091 return dm_array_walk(&cmd->info, cmd->root, __dump_mapping, NULL);
1092}
1093
1094void dm_cache_dump(struct dm_cache_metadata *cmd)
1095{
1096 down_read(&cmd->root_lock);
1097 __dump_mappings(cmd);
1098 up_read(&cmd->root_lock);
1099}
1100
1101int dm_cache_changed_this_transaction(struct dm_cache_metadata *cmd)
1102{
1103 int r;
1104
1105 down_read(&cmd->root_lock);
1106 r = cmd->changed;
1107 up_read(&cmd->root_lock);
1108
1109 return r;
1110}
1111
1112static int __dirty(struct dm_cache_metadata *cmd, dm_cblock_t cblock, bool dirty)
1113{
1114 int r;
1115 unsigned flags;
1116 dm_oblock_t oblock;
1117 __le64 value;
1118
1119 r = dm_array_get_value(&cmd->info, cmd->root, from_cblock(cblock), &value);
1120 if (r)
1121 return r;
1122
1123 unpack_value(value, &oblock, &flags);
1124
1125 if (((flags & M_DIRTY) && dirty) || (!(flags & M_DIRTY) && !dirty))
1126 /* nothing to be done */
1127 return 0;
1128
Joe Thornber79ed9ca2013-03-20 17:21:27 +00001129 value = pack_value(oblock, (flags & ~M_DIRTY) | (dirty ? M_DIRTY : 0));
Joe Thornberc6b4fcb2013-03-01 22:45:51 +00001130 __dm_bless_for_disk(&value);
1131
1132 r = dm_array_set_value(&cmd->info, cmd->root, from_cblock(cblock),
1133 &value, &cmd->root);
1134 if (r)
1135 return r;
1136
1137 cmd->changed = true;
1138 return 0;
1139
1140}
1141
1142int dm_cache_set_dirty(struct dm_cache_metadata *cmd,
1143 dm_cblock_t cblock, bool dirty)
1144{
1145 int r;
1146
1147 down_write(&cmd->root_lock);
1148 r = __dirty(cmd, cblock, dirty);
1149 up_write(&cmd->root_lock);
1150
1151 return r;
1152}
1153
1154void dm_cache_metadata_get_stats(struct dm_cache_metadata *cmd,
1155 struct dm_cache_statistics *stats)
1156{
1157 down_read(&cmd->root_lock);
Joe Thornber8c5008f2013-05-10 14:37:18 +01001158 *stats = cmd->stats;
Joe Thornberc6b4fcb2013-03-01 22:45:51 +00001159 up_read(&cmd->root_lock);
1160}
1161
1162void dm_cache_metadata_set_stats(struct dm_cache_metadata *cmd,
1163 struct dm_cache_statistics *stats)
1164{
1165 down_write(&cmd->root_lock);
Joe Thornber8c5008f2013-05-10 14:37:18 +01001166 cmd->stats = *stats;
Joe Thornberc6b4fcb2013-03-01 22:45:51 +00001167 up_write(&cmd->root_lock);
1168}
1169
1170int dm_cache_commit(struct dm_cache_metadata *cmd, bool clean_shutdown)
1171{
1172 int r;
1173 flags_mutator mutator = (clean_shutdown ? set_clean_shutdown :
1174 clear_clean_shutdown);
1175
1176 down_write(&cmd->root_lock);
1177 r = __commit_transaction(cmd, mutator);
1178 if (r)
1179 goto out;
1180
1181 r = __begin_transaction(cmd);
1182
1183out:
1184 up_write(&cmd->root_lock);
1185 return r;
1186}
1187
1188int dm_cache_get_free_metadata_block_count(struct dm_cache_metadata *cmd,
1189 dm_block_t *result)
1190{
1191 int r = -EINVAL;
1192
1193 down_read(&cmd->root_lock);
1194 r = dm_sm_get_nr_free(cmd->metadata_sm, result);
1195 up_read(&cmd->root_lock);
1196
1197 return r;
1198}
1199
1200int dm_cache_get_metadata_dev_size(struct dm_cache_metadata *cmd,
1201 dm_block_t *result)
1202{
1203 int r = -EINVAL;
1204
1205 down_read(&cmd->root_lock);
1206 r = dm_sm_get_nr_blocks(cmd->metadata_sm, result);
1207 up_read(&cmd->root_lock);
1208
1209 return r;
1210}
1211
1212/*----------------------------------------------------------------*/
1213
1214static int begin_hints(struct dm_cache_metadata *cmd, struct dm_cache_policy *policy)
1215{
1216 int r;
1217 __le32 value;
1218 size_t hint_size;
1219 const char *policy_name = dm_cache_policy_get_name(policy);
Mike Snitzer4e7f5062013-03-20 17:21:27 +00001220 const unsigned *policy_version = dm_cache_policy_get_version(policy);
Joe Thornberc6b4fcb2013-03-01 22:45:51 +00001221
1222 if (!policy_name[0] ||
1223 (strlen(policy_name) > sizeof(cmd->policy_name) - 1))
1224 return -EINVAL;
1225
Mike Snitzerea2dd8c2013-03-20 17:21:28 +00001226 if (!policy_unchanged(cmd, policy)) {
Joe Thornberc6b4fcb2013-03-01 22:45:51 +00001227 strncpy(cmd->policy_name, policy_name, sizeof(cmd->policy_name));
Mike Snitzer4e7f5062013-03-20 17:21:27 +00001228 memcpy(cmd->policy_version, policy_version, sizeof(cmd->policy_version));
Joe Thornberc6b4fcb2013-03-01 22:45:51 +00001229
1230 hint_size = dm_cache_policy_get_hint_size(policy);
1231 if (!hint_size)
1232 return 0; /* short-circuit hints initialization */
1233 cmd->policy_hint_size = hint_size;
1234
1235 if (cmd->hint_root) {
1236 r = dm_array_del(&cmd->hint_info, cmd->hint_root);
1237 if (r)
1238 return r;
1239 }
1240
1241 r = dm_array_empty(&cmd->hint_info, &cmd->hint_root);
1242 if (r)
1243 return r;
1244
1245 value = cpu_to_le32(0);
1246 __dm_bless_for_disk(&value);
1247 r = dm_array_resize(&cmd->hint_info, cmd->hint_root, 0,
1248 from_cblock(cmd->cache_blocks),
1249 &value, &cmd->hint_root);
1250 if (r)
1251 return r;
1252 }
1253
1254 return 0;
1255}
1256
Joe Thornber05966612014-04-03 16:16:44 +01001257static int save_hint(void *context, dm_cblock_t cblock, dm_oblock_t oblock, uint32_t hint)
Joe Thornberc6b4fcb2013-03-01 22:45:51 +00001258{
Joe Thornber05966612014-04-03 16:16:44 +01001259 struct dm_cache_metadata *cmd = context;
Joe Thornberc6b4fcb2013-03-01 22:45:51 +00001260 __le32 value = cpu_to_le32(hint);
Joe Thornber05966612014-04-03 16:16:44 +01001261 int r;
1262
Joe Thornberc6b4fcb2013-03-01 22:45:51 +00001263 __dm_bless_for_disk(&value);
1264
1265 r = dm_array_set_value(&cmd->hint_info, cmd->hint_root,
1266 from_cblock(cblock), &value, &cmd->hint_root);
1267 cmd->changed = true;
1268
1269 return r;
1270}
1271
Joe Thornber05966612014-04-03 16:16:44 +01001272static int write_hints(struct dm_cache_metadata *cmd, struct dm_cache_policy *policy)
Joe Thornberc6b4fcb2013-03-01 22:45:51 +00001273{
1274 int r;
1275
Joe Thornber05966612014-04-03 16:16:44 +01001276 r = begin_hints(cmd, policy);
1277 if (r) {
1278 DMERR("begin_hints failed");
1279 return r;
1280 }
1281
1282 return policy_walk_mappings(policy, save_hint, cmd);
1283}
1284
1285int dm_cache_write_hints(struct dm_cache_metadata *cmd, struct dm_cache_policy *policy)
1286{
1287 int r;
Joe Thornberc6b4fcb2013-03-01 22:45:51 +00001288
1289 down_write(&cmd->root_lock);
Joe Thornber05966612014-04-03 16:16:44 +01001290 r = write_hints(cmd, policy);
Joe Thornberc6b4fcb2013-03-01 22:45:51 +00001291 up_write(&cmd->root_lock);
1292
1293 return r;
1294}
Joe Thornber2ee57d52013-10-24 14:10:29 -04001295
1296int dm_cache_metadata_all_clean(struct dm_cache_metadata *cmd, bool *result)
1297{
1298 return blocks_are_unmapped_or_clean(cmd, 0, cmd->cache_blocks, result);
1299}