Commit | Line | Data |
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c6b4fcba JT |
1 | /* |
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 | |
53d49819 JT |
23 | |
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 | ||
c6b4fcba JT |
30 | #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 | ||
39 | enum 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 | */ | |
47 | enum 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 | ||
60 | struct 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; | |
4e7f506f MS |
92 | |
93 | __le32 policy_version[CACHE_POLICY_VERSION_SIZE]; | |
c6b4fcba JT |
94 | } __packed; |
95 | ||
96 | struct 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; | |
64ab346a | 112 | dm_oblock_t discard_nr_blocks; |
c6b4fcba JT |
113 | |
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]; | |
4e7f506f | 120 | unsigned policy_version[CACHE_POLICY_VERSION_SIZE]; |
c6b4fcba JT |
121 | size_t policy_hint_size; |
122 | struct dm_cache_statistics stats; | |
123 | }; | |
124 | ||
125 | /*------------------------------------------------------------------- | |
126 | * superblock validator | |
127 | *-----------------------------------------------------------------*/ | |
128 | ||
129 | #define SUPERBLOCK_CSUM_XOR 9031977 | |
130 | ||
131 | static void sb_prepare_for_write(struct dm_block_validator *v, | |
132 | struct dm_block *b, | |
133 | size_t sb_block_size) | |
134 | { | |
135 | struct cache_disk_superblock *disk_super = dm_block_data(b); | |
136 | ||
137 | disk_super->blocknr = cpu_to_le64(dm_block_location(b)); | |
138 | disk_super->csum = cpu_to_le32(dm_bm_checksum(&disk_super->flags, | |
139 | sb_block_size - sizeof(__le32), | |
140 | SUPERBLOCK_CSUM_XOR)); | |
141 | } | |
142 | ||
53d49819 JT |
143 | static int check_metadata_version(struct cache_disk_superblock *disk_super) |
144 | { | |
145 | uint32_t metadata_version = le32_to_cpu(disk_super->version); | |
146 | if (metadata_version < MIN_CACHE_VERSION || metadata_version > MAX_CACHE_VERSION) { | |
147 | DMERR("Cache metadata version %u found, but only versions between %u and %u supported.", | |
148 | metadata_version, MIN_CACHE_VERSION, MAX_CACHE_VERSION); | |
149 | return -EINVAL; | |
150 | } | |
151 | ||
152 | return 0; | |
153 | } | |
154 | ||
c6b4fcba JT |
155 | static int sb_check(struct dm_block_validator *v, |
156 | struct dm_block *b, | |
157 | size_t sb_block_size) | |
158 | { | |
159 | struct cache_disk_superblock *disk_super = dm_block_data(b); | |
160 | __le32 csum_le; | |
161 | ||
162 | if (dm_block_location(b) != le64_to_cpu(disk_super->blocknr)) { | |
163 | DMERR("sb_check failed: blocknr %llu: wanted %llu", | |
164 | le64_to_cpu(disk_super->blocknr), | |
165 | (unsigned long long)dm_block_location(b)); | |
166 | return -ENOTBLK; | |
167 | } | |
168 | ||
169 | if (le64_to_cpu(disk_super->magic) != CACHE_SUPERBLOCK_MAGIC) { | |
170 | DMERR("sb_check failed: magic %llu: wanted %llu", | |
171 | le64_to_cpu(disk_super->magic), | |
172 | (unsigned long long)CACHE_SUPERBLOCK_MAGIC); | |
173 | return -EILSEQ; | |
174 | } | |
175 | ||
176 | csum_le = cpu_to_le32(dm_bm_checksum(&disk_super->flags, | |
177 | sb_block_size - sizeof(__le32), | |
178 | SUPERBLOCK_CSUM_XOR)); | |
179 | if (csum_le != disk_super->csum) { | |
180 | DMERR("sb_check failed: csum %u: wanted %u", | |
181 | le32_to_cpu(csum_le), le32_to_cpu(disk_super->csum)); | |
182 | return -EILSEQ; | |
183 | } | |
184 | ||
53d49819 | 185 | return check_metadata_version(disk_super); |
c6b4fcba JT |
186 | } |
187 | ||
188 | static struct dm_block_validator sb_validator = { | |
189 | .name = "superblock", | |
190 | .prepare_for_write = sb_prepare_for_write, | |
191 | .check = sb_check | |
192 | }; | |
193 | ||
194 | /*----------------------------------------------------------------*/ | |
195 | ||
196 | static int superblock_read_lock(struct dm_cache_metadata *cmd, | |
197 | struct dm_block **sblock) | |
198 | { | |
199 | return dm_bm_read_lock(cmd->bm, CACHE_SUPERBLOCK_LOCATION, | |
200 | &sb_validator, sblock); | |
201 | } | |
202 | ||
203 | static int superblock_lock_zero(struct dm_cache_metadata *cmd, | |
204 | struct dm_block **sblock) | |
205 | { | |
206 | return dm_bm_write_lock_zero(cmd->bm, CACHE_SUPERBLOCK_LOCATION, | |
207 | &sb_validator, sblock); | |
208 | } | |
209 | ||
210 | static int superblock_lock(struct dm_cache_metadata *cmd, | |
211 | struct dm_block **sblock) | |
212 | { | |
213 | return dm_bm_write_lock(cmd->bm, CACHE_SUPERBLOCK_LOCATION, | |
214 | &sb_validator, sblock); | |
215 | } | |
216 | ||
217 | /*----------------------------------------------------------------*/ | |
218 | ||
dd8b0c20 | 219 | static int __superblock_all_zeroes(struct dm_block_manager *bm, bool *result) |
c6b4fcba JT |
220 | { |
221 | int r; | |
222 | unsigned i; | |
223 | struct dm_block *b; | |
224 | __le64 *data_le, zero = cpu_to_le64(0); | |
225 | unsigned sb_block_size = dm_bm_block_size(bm) / sizeof(__le64); | |
226 | ||
227 | /* | |
228 | * We can't use a validator here - it may be all zeroes. | |
229 | */ | |
230 | r = dm_bm_read_lock(bm, CACHE_SUPERBLOCK_LOCATION, NULL, &b); | |
231 | if (r) | |
232 | return r; | |
233 | ||
234 | data_le = dm_block_data(b); | |
dd8b0c20 | 235 | *result = true; |
c6b4fcba JT |
236 | for (i = 0; i < sb_block_size; i++) { |
237 | if (data_le[i] != zero) { | |
dd8b0c20 | 238 | *result = false; |
c6b4fcba JT |
239 | break; |
240 | } | |
241 | } | |
242 | ||
243 | return dm_bm_unlock(b); | |
244 | } | |
245 | ||
246 | static void __setup_mapping_info(struct dm_cache_metadata *cmd) | |
247 | { | |
248 | struct dm_btree_value_type vt; | |
249 | ||
250 | vt.context = NULL; | |
251 | vt.size = sizeof(__le64); | |
252 | vt.inc = NULL; | |
253 | vt.dec = NULL; | |
254 | vt.equal = NULL; | |
255 | dm_array_info_init(&cmd->info, cmd->tm, &vt); | |
256 | ||
257 | if (cmd->policy_hint_size) { | |
258 | vt.size = sizeof(__le32); | |
259 | dm_array_info_init(&cmd->hint_info, cmd->tm, &vt); | |
260 | } | |
261 | } | |
262 | ||
263 | static int __write_initial_superblock(struct dm_cache_metadata *cmd) | |
264 | { | |
265 | int r; | |
266 | struct dm_block *sblock; | |
267 | size_t metadata_len; | |
268 | struct cache_disk_superblock *disk_super; | |
269 | sector_t bdev_size = i_size_read(cmd->bdev->bd_inode) >> SECTOR_SHIFT; | |
270 | ||
271 | /* FIXME: see if we can lose the max sectors limit */ | |
272 | if (bdev_size > DM_CACHE_METADATA_MAX_SECTORS) | |
273 | bdev_size = DM_CACHE_METADATA_MAX_SECTORS; | |
274 | ||
275 | r = dm_sm_root_size(cmd->metadata_sm, &metadata_len); | |
276 | if (r < 0) | |
277 | return r; | |
278 | ||
279 | r = dm_tm_pre_commit(cmd->tm); | |
280 | if (r < 0) | |
281 | return r; | |
282 | ||
283 | r = superblock_lock_zero(cmd, &sblock); | |
284 | if (r) | |
285 | return r; | |
286 | ||
287 | disk_super = dm_block_data(sblock); | |
288 | disk_super->flags = 0; | |
289 | memset(disk_super->uuid, 0, sizeof(disk_super->uuid)); | |
290 | disk_super->magic = cpu_to_le64(CACHE_SUPERBLOCK_MAGIC); | |
53d49819 | 291 | disk_super->version = cpu_to_le32(MAX_CACHE_VERSION); |
4e7f506f MS |
292 | memset(disk_super->policy_name, 0, sizeof(disk_super->policy_name)); |
293 | memset(disk_super->policy_version, 0, sizeof(disk_super->policy_version)); | |
c6b4fcba JT |
294 | disk_super->policy_hint_size = 0; |
295 | ||
296 | r = dm_sm_copy_root(cmd->metadata_sm, &disk_super->metadata_space_map_root, | |
297 | metadata_len); | |
298 | if (r < 0) | |
299 | goto bad_locked; | |
300 | ||
301 | disk_super->mapping_root = cpu_to_le64(cmd->root); | |
302 | disk_super->hint_root = cpu_to_le64(cmd->hint_root); | |
303 | disk_super->discard_root = cpu_to_le64(cmd->discard_root); | |
304 | disk_super->discard_block_size = cpu_to_le64(cmd->discard_block_size); | |
64ab346a | 305 | disk_super->discard_nr_blocks = cpu_to_le64(from_oblock(cmd->discard_nr_blocks)); |
c6b4fcba JT |
306 | disk_super->metadata_block_size = cpu_to_le32(DM_CACHE_METADATA_BLOCK_SIZE >> SECTOR_SHIFT); |
307 | disk_super->data_block_size = cpu_to_le32(cmd->data_block_size); | |
308 | disk_super->cache_blocks = cpu_to_le32(0); | |
c6b4fcba JT |
309 | |
310 | disk_super->read_hits = cpu_to_le32(0); | |
311 | disk_super->read_misses = cpu_to_le32(0); | |
312 | disk_super->write_hits = cpu_to_le32(0); | |
313 | disk_super->write_misses = cpu_to_le32(0); | |
314 | ||
315 | return dm_tm_commit(cmd->tm, sblock); | |
316 | ||
317 | bad_locked: | |
318 | dm_bm_unlock(sblock); | |
319 | return r; | |
320 | } | |
321 | ||
322 | static int __format_metadata(struct dm_cache_metadata *cmd) | |
323 | { | |
324 | int r; | |
325 | ||
326 | r = dm_tm_create_with_sm(cmd->bm, CACHE_SUPERBLOCK_LOCATION, | |
327 | &cmd->tm, &cmd->metadata_sm); | |
328 | if (r < 0) { | |
329 | DMERR("tm_create_with_sm failed"); | |
330 | return r; | |
331 | } | |
332 | ||
333 | __setup_mapping_info(cmd); | |
334 | ||
335 | r = dm_array_empty(&cmd->info, &cmd->root); | |
336 | if (r < 0) | |
337 | goto bad; | |
338 | ||
339 | dm_disk_bitset_init(cmd->tm, &cmd->discard_info); | |
340 | ||
341 | r = dm_bitset_empty(&cmd->discard_info, &cmd->discard_root); | |
342 | if (r < 0) | |
343 | goto bad; | |
344 | ||
345 | cmd->discard_block_size = 0; | |
346 | cmd->discard_nr_blocks = 0; | |
347 | ||
348 | r = __write_initial_superblock(cmd); | |
349 | if (r) | |
350 | goto bad; | |
351 | ||
352 | cmd->clean_when_opened = true; | |
353 | return 0; | |
354 | ||
355 | bad: | |
356 | dm_tm_destroy(cmd->tm); | |
357 | dm_sm_destroy(cmd->metadata_sm); | |
358 | ||
359 | return r; | |
360 | } | |
361 | ||
362 | static int __check_incompat_features(struct cache_disk_superblock *disk_super, | |
363 | struct dm_cache_metadata *cmd) | |
364 | { | |
365 | uint32_t features; | |
366 | ||
367 | features = le32_to_cpu(disk_super->incompat_flags) & ~DM_CACHE_FEATURE_INCOMPAT_SUPP; | |
368 | if (features) { | |
369 | DMERR("could not access metadata due to unsupported optional features (%lx).", | |
370 | (unsigned long)features); | |
371 | return -EINVAL; | |
372 | } | |
373 | ||
374 | /* | |
375 | * Check for read-only metadata to skip the following RDWR checks. | |
376 | */ | |
377 | if (get_disk_ro(cmd->bdev->bd_disk)) | |
378 | return 0; | |
379 | ||
380 | features = le32_to_cpu(disk_super->compat_ro_flags) & ~DM_CACHE_FEATURE_COMPAT_RO_SUPP; | |
381 | if (features) { | |
382 | DMERR("could not access metadata RDWR due to unsupported optional features (%lx).", | |
383 | (unsigned long)features); | |
384 | return -EINVAL; | |
385 | } | |
386 | ||
387 | return 0; | |
388 | } | |
389 | ||
390 | static int __open_metadata(struct dm_cache_metadata *cmd) | |
391 | { | |
392 | int r; | |
393 | struct dm_block *sblock; | |
394 | struct cache_disk_superblock *disk_super; | |
395 | unsigned long sb_flags; | |
396 | ||
397 | r = superblock_read_lock(cmd, &sblock); | |
398 | if (r < 0) { | |
399 | DMERR("couldn't read lock superblock"); | |
400 | return r; | |
401 | } | |
402 | ||
403 | disk_super = dm_block_data(sblock); | |
404 | ||
405 | r = __check_incompat_features(disk_super, cmd); | |
406 | if (r < 0) | |
407 | goto bad; | |
408 | ||
409 | r = dm_tm_open_with_sm(cmd->bm, CACHE_SUPERBLOCK_LOCATION, | |
410 | disk_super->metadata_space_map_root, | |
411 | sizeof(disk_super->metadata_space_map_root), | |
412 | &cmd->tm, &cmd->metadata_sm); | |
413 | if (r < 0) { | |
414 | DMERR("tm_open_with_sm failed"); | |
415 | goto bad; | |
416 | } | |
417 | ||
418 | __setup_mapping_info(cmd); | |
419 | dm_disk_bitset_init(cmd->tm, &cmd->discard_info); | |
420 | sb_flags = le32_to_cpu(disk_super->flags); | |
421 | cmd->clean_when_opened = test_bit(CLEAN_SHUTDOWN, &sb_flags); | |
422 | return dm_bm_unlock(sblock); | |
423 | ||
424 | bad: | |
425 | dm_bm_unlock(sblock); | |
426 | return r; | |
427 | } | |
428 | ||
429 | static int __open_or_format_metadata(struct dm_cache_metadata *cmd, | |
430 | bool format_device) | |
431 | { | |
dd8b0c20 JT |
432 | int r; |
433 | bool unformatted = false; | |
c6b4fcba JT |
434 | |
435 | r = __superblock_all_zeroes(cmd->bm, &unformatted); | |
436 | if (r) | |
437 | return r; | |
438 | ||
439 | if (unformatted) | |
440 | return format_device ? __format_metadata(cmd) : -EPERM; | |
441 | ||
442 | return __open_metadata(cmd); | |
443 | } | |
444 | ||
445 | static int __create_persistent_data_objects(struct dm_cache_metadata *cmd, | |
446 | bool may_format_device) | |
447 | { | |
448 | int r; | |
449 | cmd->bm = dm_block_manager_create(cmd->bdev, DM_CACHE_METADATA_BLOCK_SIZE, | |
450 | CACHE_METADATA_CACHE_SIZE, | |
451 | CACHE_MAX_CONCURRENT_LOCKS); | |
452 | if (IS_ERR(cmd->bm)) { | |
453 | DMERR("could not create block manager"); | |
454 | return PTR_ERR(cmd->bm); | |
455 | } | |
456 | ||
457 | r = __open_or_format_metadata(cmd, may_format_device); | |
458 | if (r) | |
459 | dm_block_manager_destroy(cmd->bm); | |
460 | ||
461 | return r; | |
462 | } | |
463 | ||
464 | static void __destroy_persistent_data_objects(struct dm_cache_metadata *cmd) | |
465 | { | |
466 | dm_sm_destroy(cmd->metadata_sm); | |
467 | dm_tm_destroy(cmd->tm); | |
468 | dm_block_manager_destroy(cmd->bm); | |
469 | } | |
470 | ||
471 | typedef unsigned long (*flags_mutator)(unsigned long); | |
472 | ||
473 | static void update_flags(struct cache_disk_superblock *disk_super, | |
474 | flags_mutator mutator) | |
475 | { | |
476 | uint32_t sb_flags = mutator(le32_to_cpu(disk_super->flags)); | |
477 | disk_super->flags = cpu_to_le32(sb_flags); | |
478 | } | |
479 | ||
480 | static unsigned long set_clean_shutdown(unsigned long flags) | |
481 | { | |
482 | set_bit(CLEAN_SHUTDOWN, &flags); | |
483 | return flags; | |
484 | } | |
485 | ||
486 | static unsigned long clear_clean_shutdown(unsigned long flags) | |
487 | { | |
488 | clear_bit(CLEAN_SHUTDOWN, &flags); | |
489 | return flags; | |
490 | } | |
491 | ||
492 | static void read_superblock_fields(struct dm_cache_metadata *cmd, | |
493 | struct cache_disk_superblock *disk_super) | |
494 | { | |
495 | cmd->root = le64_to_cpu(disk_super->mapping_root); | |
496 | cmd->hint_root = le64_to_cpu(disk_super->hint_root); | |
497 | cmd->discard_root = le64_to_cpu(disk_super->discard_root); | |
498 | cmd->discard_block_size = le64_to_cpu(disk_super->discard_block_size); | |
64ab346a | 499 | cmd->discard_nr_blocks = to_oblock(le64_to_cpu(disk_super->discard_nr_blocks)); |
c6b4fcba JT |
500 | cmd->data_block_size = le32_to_cpu(disk_super->data_block_size); |
501 | cmd->cache_blocks = to_cblock(le32_to_cpu(disk_super->cache_blocks)); | |
502 | strncpy(cmd->policy_name, disk_super->policy_name, sizeof(cmd->policy_name)); | |
4e7f506f MS |
503 | cmd->policy_version[0] = le32_to_cpu(disk_super->policy_version[0]); |
504 | cmd->policy_version[1] = le32_to_cpu(disk_super->policy_version[1]); | |
505 | cmd->policy_version[2] = le32_to_cpu(disk_super->policy_version[2]); | |
c6b4fcba JT |
506 | cmd->policy_hint_size = le32_to_cpu(disk_super->policy_hint_size); |
507 | ||
508 | cmd->stats.read_hits = le32_to_cpu(disk_super->read_hits); | |
509 | cmd->stats.read_misses = le32_to_cpu(disk_super->read_misses); | |
510 | cmd->stats.write_hits = le32_to_cpu(disk_super->write_hits); | |
511 | cmd->stats.write_misses = le32_to_cpu(disk_super->write_misses); | |
512 | ||
513 | cmd->changed = false; | |
514 | } | |
515 | ||
516 | /* | |
517 | * The mutator updates the superblock flags. | |
518 | */ | |
519 | static int __begin_transaction_flags(struct dm_cache_metadata *cmd, | |
520 | flags_mutator mutator) | |
521 | { | |
522 | int r; | |
523 | struct cache_disk_superblock *disk_super; | |
524 | struct dm_block *sblock; | |
525 | ||
526 | r = superblock_lock(cmd, &sblock); | |
527 | if (r) | |
528 | return r; | |
529 | ||
530 | disk_super = dm_block_data(sblock); | |
531 | update_flags(disk_super, mutator); | |
532 | read_superblock_fields(cmd, disk_super); | |
533 | ||
534 | return dm_bm_flush_and_unlock(cmd->bm, sblock); | |
535 | } | |
536 | ||
537 | static int __begin_transaction(struct dm_cache_metadata *cmd) | |
538 | { | |
539 | int r; | |
540 | struct cache_disk_superblock *disk_super; | |
541 | struct dm_block *sblock; | |
542 | ||
543 | /* | |
544 | * We re-read the superblock every time. Shouldn't need to do this | |
545 | * really. | |
546 | */ | |
547 | r = superblock_read_lock(cmd, &sblock); | |
548 | if (r) | |
549 | return r; | |
550 | ||
551 | disk_super = dm_block_data(sblock); | |
552 | read_superblock_fields(cmd, disk_super); | |
553 | dm_bm_unlock(sblock); | |
554 | ||
555 | return 0; | |
556 | } | |
557 | ||
558 | static int __commit_transaction(struct dm_cache_metadata *cmd, | |
559 | flags_mutator mutator) | |
560 | { | |
561 | int r; | |
562 | size_t metadata_len; | |
563 | struct cache_disk_superblock *disk_super; | |
564 | struct dm_block *sblock; | |
565 | ||
566 | /* | |
567 | * We need to know if the cache_disk_superblock exceeds a 512-byte sector. | |
568 | */ | |
569 | BUILD_BUG_ON(sizeof(struct cache_disk_superblock) > 512); | |
570 | ||
571 | r = dm_bitset_flush(&cmd->discard_info, cmd->discard_root, | |
572 | &cmd->discard_root); | |
573 | if (r) | |
574 | return r; | |
575 | ||
576 | r = dm_tm_pre_commit(cmd->tm); | |
577 | if (r < 0) | |
578 | return r; | |
579 | ||
580 | r = dm_sm_root_size(cmd->metadata_sm, &metadata_len); | |
581 | if (r < 0) | |
582 | return r; | |
583 | ||
584 | r = superblock_lock(cmd, &sblock); | |
585 | if (r) | |
586 | return r; | |
587 | ||
588 | disk_super = dm_block_data(sblock); | |
589 | ||
590 | if (mutator) | |
591 | update_flags(disk_super, mutator); | |
592 | ||
593 | disk_super->mapping_root = cpu_to_le64(cmd->root); | |
594 | disk_super->hint_root = cpu_to_le64(cmd->hint_root); | |
595 | disk_super->discard_root = cpu_to_le64(cmd->discard_root); | |
596 | disk_super->discard_block_size = cpu_to_le64(cmd->discard_block_size); | |
64ab346a | 597 | disk_super->discard_nr_blocks = cpu_to_le64(from_oblock(cmd->discard_nr_blocks)); |
c6b4fcba JT |
598 | disk_super->cache_blocks = cpu_to_le32(from_cblock(cmd->cache_blocks)); |
599 | strncpy(disk_super->policy_name, cmd->policy_name, sizeof(disk_super->policy_name)); | |
4e7f506f MS |
600 | disk_super->policy_version[0] = cpu_to_le32(cmd->policy_version[0]); |
601 | disk_super->policy_version[1] = cpu_to_le32(cmd->policy_version[1]); | |
602 | disk_super->policy_version[2] = cpu_to_le32(cmd->policy_version[2]); | |
c6b4fcba JT |
603 | |
604 | disk_super->read_hits = cpu_to_le32(cmd->stats.read_hits); | |
605 | disk_super->read_misses = cpu_to_le32(cmd->stats.read_misses); | |
606 | disk_super->write_hits = cpu_to_le32(cmd->stats.write_hits); | |
607 | disk_super->write_misses = cpu_to_le32(cmd->stats.write_misses); | |
608 | ||
609 | r = dm_sm_copy_root(cmd->metadata_sm, &disk_super->metadata_space_map_root, | |
610 | metadata_len); | |
611 | if (r < 0) { | |
612 | dm_bm_unlock(sblock); | |
613 | return r; | |
614 | } | |
615 | ||
616 | return dm_tm_commit(cmd->tm, sblock); | |
617 | } | |
618 | ||
619 | /*----------------------------------------------------------------*/ | |
620 | ||
621 | /* | |
622 | * The mappings are held in a dm-array that has 64-bit values stored in | |
623 | * little-endian format. The index is the cblock, the high 48bits of the | |
624 | * value are the oblock and the low 16 bit the flags. | |
625 | */ | |
626 | #define FLAGS_MASK ((1 << 16) - 1) | |
627 | ||
628 | static __le64 pack_value(dm_oblock_t block, unsigned flags) | |
629 | { | |
630 | uint64_t value = from_oblock(block); | |
631 | value <<= 16; | |
632 | value = value | (flags & FLAGS_MASK); | |
633 | return cpu_to_le64(value); | |
634 | } | |
635 | ||
636 | static void unpack_value(__le64 value_le, dm_oblock_t *block, unsigned *flags) | |
637 | { | |
638 | uint64_t value = le64_to_cpu(value_le); | |
639 | uint64_t b = value >> 16; | |
640 | *block = to_oblock(b); | |
641 | *flags = value & FLAGS_MASK; | |
642 | } | |
643 | ||
644 | /*----------------------------------------------------------------*/ | |
645 | ||
646 | struct dm_cache_metadata *dm_cache_metadata_open(struct block_device *bdev, | |
647 | sector_t data_block_size, | |
648 | bool may_format_device, | |
649 | size_t policy_hint_size) | |
650 | { | |
651 | int r; | |
652 | struct dm_cache_metadata *cmd; | |
653 | ||
654 | cmd = kzalloc(sizeof(*cmd), GFP_KERNEL); | |
655 | if (!cmd) { | |
656 | DMERR("could not allocate metadata struct"); | |
657 | return NULL; | |
658 | } | |
659 | ||
660 | init_rwsem(&cmd->root_lock); | |
661 | cmd->bdev = bdev; | |
662 | cmd->data_block_size = data_block_size; | |
663 | cmd->cache_blocks = 0; | |
664 | cmd->policy_hint_size = policy_hint_size; | |
665 | cmd->changed = true; | |
666 | ||
667 | r = __create_persistent_data_objects(cmd, may_format_device); | |
668 | if (r) { | |
669 | kfree(cmd); | |
670 | return ERR_PTR(r); | |
671 | } | |
672 | ||
673 | r = __begin_transaction_flags(cmd, clear_clean_shutdown); | |
674 | if (r < 0) { | |
675 | dm_cache_metadata_close(cmd); | |
676 | return ERR_PTR(r); | |
677 | } | |
678 | ||
679 | return cmd; | |
680 | } | |
681 | ||
682 | void dm_cache_metadata_close(struct dm_cache_metadata *cmd) | |
683 | { | |
684 | __destroy_persistent_data_objects(cmd); | |
685 | kfree(cmd); | |
686 | } | |
687 | ||
f494a9c6 JT |
688 | /* |
689 | * Checks that the given cache block is either unmapped or clean. | |
690 | */ | |
691 | static int block_unmapped_or_clean(struct dm_cache_metadata *cmd, dm_cblock_t b, | |
692 | bool *result) | |
693 | { | |
694 | int r; | |
695 | __le64 value; | |
696 | dm_oblock_t ob; | |
697 | unsigned flags; | |
698 | ||
699 | r = dm_array_get_value(&cmd->info, cmd->root, from_cblock(b), &value); | |
700 | if (r) { | |
701 | DMERR("block_unmapped_or_clean failed"); | |
702 | return r; | |
703 | } | |
704 | ||
705 | unpack_value(value, &ob, &flags); | |
706 | *result = !((flags & M_VALID) && (flags & M_DIRTY)); | |
707 | ||
708 | return 0; | |
709 | } | |
710 | ||
711 | static int blocks_are_unmapped_or_clean(struct dm_cache_metadata *cmd, | |
712 | dm_cblock_t begin, dm_cblock_t end, | |
713 | bool *result) | |
714 | { | |
715 | int r; | |
716 | *result = true; | |
717 | ||
718 | while (begin != end) { | |
719 | r = block_unmapped_or_clean(cmd, begin, result); | |
720 | if (r) | |
721 | return r; | |
722 | ||
723 | if (!*result) { | |
724 | DMERR("cache block %llu is dirty", | |
725 | (unsigned long long) from_cblock(begin)); | |
726 | return 0; | |
727 | } | |
728 | ||
729 | begin = to_cblock(from_cblock(begin) + 1); | |
730 | } | |
731 | ||
732 | return 0; | |
733 | } | |
734 | ||
c6b4fcba JT |
735 | int dm_cache_resize(struct dm_cache_metadata *cmd, dm_cblock_t new_cache_size) |
736 | { | |
737 | int r; | |
f494a9c6 | 738 | bool clean; |
c6b4fcba JT |
739 | __le64 null_mapping = pack_value(0, 0); |
740 | ||
741 | down_write(&cmd->root_lock); | |
742 | __dm_bless_for_disk(&null_mapping); | |
f494a9c6 JT |
743 | |
744 | if (from_cblock(new_cache_size) < from_cblock(cmd->cache_blocks)) { | |
745 | r = blocks_are_unmapped_or_clean(cmd, new_cache_size, cmd->cache_blocks, &clean); | |
746 | if (r) { | |
747 | __dm_unbless_for_disk(&null_mapping); | |
748 | goto out; | |
749 | } | |
750 | ||
751 | if (!clean) { | |
752 | DMERR("unable to shrink cache due to dirty blocks"); | |
753 | r = -EINVAL; | |
754 | __dm_unbless_for_disk(&null_mapping); | |
755 | goto out; | |
756 | } | |
757 | } | |
758 | ||
c6b4fcba JT |
759 | r = dm_array_resize(&cmd->info, cmd->root, from_cblock(cmd->cache_blocks), |
760 | from_cblock(new_cache_size), | |
761 | &null_mapping, &cmd->root); | |
762 | if (!r) | |
763 | cmd->cache_blocks = new_cache_size; | |
764 | cmd->changed = true; | |
f494a9c6 JT |
765 | |
766 | out: | |
c6b4fcba JT |
767 | up_write(&cmd->root_lock); |
768 | ||
769 | return r; | |
770 | } | |
771 | ||
772 | int dm_cache_discard_bitset_resize(struct dm_cache_metadata *cmd, | |
773 | sector_t discard_block_size, | |
64ab346a | 774 | dm_oblock_t new_nr_entries) |
c6b4fcba JT |
775 | { |
776 | int r; | |
777 | ||
778 | down_write(&cmd->root_lock); | |
779 | r = dm_bitset_resize(&cmd->discard_info, | |
780 | cmd->discard_root, | |
64ab346a HM |
781 | from_oblock(cmd->discard_nr_blocks), |
782 | from_oblock(new_nr_entries), | |
c6b4fcba JT |
783 | false, &cmd->discard_root); |
784 | if (!r) { | |
785 | cmd->discard_block_size = discard_block_size; | |
786 | cmd->discard_nr_blocks = new_nr_entries; | |
787 | } | |
788 | ||
789 | cmd->changed = true; | |
790 | up_write(&cmd->root_lock); | |
791 | ||
792 | return r; | |
793 | } | |
794 | ||
64ab346a | 795 | static int __set_discard(struct dm_cache_metadata *cmd, dm_oblock_t b) |
c6b4fcba JT |
796 | { |
797 | return dm_bitset_set_bit(&cmd->discard_info, cmd->discard_root, | |
64ab346a | 798 | from_oblock(b), &cmd->discard_root); |
c6b4fcba JT |
799 | } |
800 | ||
64ab346a | 801 | static int __clear_discard(struct dm_cache_metadata *cmd, dm_oblock_t b) |
c6b4fcba JT |
802 | { |
803 | return dm_bitset_clear_bit(&cmd->discard_info, cmd->discard_root, | |
64ab346a | 804 | from_oblock(b), &cmd->discard_root); |
c6b4fcba JT |
805 | } |
806 | ||
64ab346a | 807 | static int __is_discarded(struct dm_cache_metadata *cmd, dm_oblock_t b, |
c6b4fcba JT |
808 | bool *is_discarded) |
809 | { | |
810 | return dm_bitset_test_bit(&cmd->discard_info, cmd->discard_root, | |
64ab346a | 811 | from_oblock(b), &cmd->discard_root, |
c6b4fcba JT |
812 | is_discarded); |
813 | } | |
814 | ||
815 | static int __discard(struct dm_cache_metadata *cmd, | |
64ab346a | 816 | dm_oblock_t dblock, bool discard) |
c6b4fcba JT |
817 | { |
818 | int r; | |
819 | ||
820 | r = (discard ? __set_discard : __clear_discard)(cmd, dblock); | |
821 | if (r) | |
822 | return r; | |
823 | ||
824 | cmd->changed = true; | |
825 | return 0; | |
826 | } | |
827 | ||
828 | int dm_cache_set_discard(struct dm_cache_metadata *cmd, | |
64ab346a | 829 | dm_oblock_t dblock, bool discard) |
c6b4fcba JT |
830 | { |
831 | int r; | |
832 | ||
833 | down_write(&cmd->root_lock); | |
834 | r = __discard(cmd, dblock, discard); | |
835 | up_write(&cmd->root_lock); | |
836 | ||
837 | return r; | |
838 | } | |
839 | ||
840 | static int __load_discards(struct dm_cache_metadata *cmd, | |
841 | load_discard_fn fn, void *context) | |
842 | { | |
843 | int r = 0; | |
844 | dm_block_t b; | |
845 | bool discard; | |
846 | ||
64ab346a HM |
847 | for (b = 0; b < from_oblock(cmd->discard_nr_blocks); b++) { |
848 | dm_oblock_t dblock = to_oblock(b); | |
c6b4fcba JT |
849 | |
850 | if (cmd->clean_when_opened) { | |
851 | r = __is_discarded(cmd, dblock, &discard); | |
852 | if (r) | |
853 | return r; | |
854 | } else | |
855 | discard = false; | |
856 | ||
857 | r = fn(context, cmd->discard_block_size, dblock, discard); | |
858 | if (r) | |
859 | break; | |
860 | } | |
861 | ||
862 | return r; | |
863 | } | |
864 | ||
865 | int dm_cache_load_discards(struct dm_cache_metadata *cmd, | |
866 | load_discard_fn fn, void *context) | |
867 | { | |
868 | int r; | |
869 | ||
870 | down_read(&cmd->root_lock); | |
871 | r = __load_discards(cmd, fn, context); | |
872 | up_read(&cmd->root_lock); | |
873 | ||
874 | return r; | |
875 | } | |
876 | ||
877 | dm_cblock_t dm_cache_size(struct dm_cache_metadata *cmd) | |
878 | { | |
879 | dm_cblock_t r; | |
880 | ||
881 | down_read(&cmd->root_lock); | |
882 | r = cmd->cache_blocks; | |
883 | up_read(&cmd->root_lock); | |
884 | ||
885 | return r; | |
886 | } | |
887 | ||
888 | static int __remove(struct dm_cache_metadata *cmd, dm_cblock_t cblock) | |
889 | { | |
890 | int r; | |
891 | __le64 value = pack_value(0, 0); | |
892 | ||
893 | __dm_bless_for_disk(&value); | |
894 | r = dm_array_set_value(&cmd->info, cmd->root, from_cblock(cblock), | |
895 | &value, &cmd->root); | |
896 | if (r) | |
897 | return r; | |
898 | ||
899 | cmd->changed = true; | |
900 | return 0; | |
901 | } | |
902 | ||
903 | int dm_cache_remove_mapping(struct dm_cache_metadata *cmd, dm_cblock_t cblock) | |
904 | { | |
905 | int r; | |
906 | ||
907 | down_write(&cmd->root_lock); | |
908 | r = __remove(cmd, cblock); | |
909 | up_write(&cmd->root_lock); | |
910 | ||
911 | return r; | |
912 | } | |
913 | ||
914 | static int __insert(struct dm_cache_metadata *cmd, | |
915 | dm_cblock_t cblock, dm_oblock_t oblock) | |
916 | { | |
917 | int r; | |
918 | __le64 value = pack_value(oblock, M_VALID); | |
919 | __dm_bless_for_disk(&value); | |
920 | ||
921 | r = dm_array_set_value(&cmd->info, cmd->root, from_cblock(cblock), | |
922 | &value, &cmd->root); | |
923 | if (r) | |
924 | return r; | |
925 | ||
926 | cmd->changed = true; | |
927 | return 0; | |
928 | } | |
929 | ||
930 | int dm_cache_insert_mapping(struct dm_cache_metadata *cmd, | |
931 | dm_cblock_t cblock, dm_oblock_t oblock) | |
932 | { | |
933 | int r; | |
934 | ||
935 | down_write(&cmd->root_lock); | |
936 | r = __insert(cmd, cblock, oblock); | |
937 | up_write(&cmd->root_lock); | |
938 | ||
939 | return r; | |
940 | } | |
941 | ||
942 | struct thunk { | |
943 | load_mapping_fn fn; | |
944 | void *context; | |
945 | ||
946 | struct dm_cache_metadata *cmd; | |
947 | bool respect_dirty_flags; | |
948 | bool hints_valid; | |
949 | }; | |
950 | ||
ea2dd8c1 MS |
951 | static bool policy_unchanged(struct dm_cache_metadata *cmd, |
952 | struct dm_cache_policy *policy) | |
953 | { | |
954 | const char *policy_name = dm_cache_policy_get_name(policy); | |
955 | const unsigned *policy_version = dm_cache_policy_get_version(policy); | |
956 | size_t policy_hint_size = dm_cache_policy_get_hint_size(policy); | |
957 | ||
958 | /* | |
959 | * Ensure policy names match. | |
960 | */ | |
961 | if (strncmp(cmd->policy_name, policy_name, sizeof(cmd->policy_name))) | |
962 | return false; | |
963 | ||
964 | /* | |
965 | * Ensure policy major versions match. | |
966 | */ | |
967 | if (cmd->policy_version[0] != policy_version[0]) | |
968 | return false; | |
969 | ||
970 | /* | |
971 | * Ensure policy hint sizes match. | |
972 | */ | |
973 | if (cmd->policy_hint_size != policy_hint_size) | |
974 | return false; | |
975 | ||
976 | return true; | |
977 | } | |
978 | ||
c6b4fcba JT |
979 | static bool hints_array_initialized(struct dm_cache_metadata *cmd) |
980 | { | |
981 | return cmd->hint_root && cmd->policy_hint_size; | |
982 | } | |
983 | ||
984 | static bool hints_array_available(struct dm_cache_metadata *cmd, | |
ea2dd8c1 | 985 | struct dm_cache_policy *policy) |
c6b4fcba | 986 | { |
ea2dd8c1 | 987 | return cmd->clean_when_opened && policy_unchanged(cmd, policy) && |
c6b4fcba JT |
988 | hints_array_initialized(cmd); |
989 | } | |
990 | ||
991 | static int __load_mapping(void *context, uint64_t cblock, void *leaf) | |
992 | { | |
993 | int r = 0; | |
994 | bool dirty; | |
995 | __le64 value; | |
996 | __le32 hint_value = 0; | |
997 | dm_oblock_t oblock; | |
998 | unsigned flags; | |
999 | struct thunk *thunk = context; | |
1000 | struct dm_cache_metadata *cmd = thunk->cmd; | |
1001 | ||
1002 | memcpy(&value, leaf, sizeof(value)); | |
1003 | unpack_value(value, &oblock, &flags); | |
1004 | ||
1005 | if (flags & M_VALID) { | |
1006 | if (thunk->hints_valid) { | |
1007 | r = dm_array_get_value(&cmd->hint_info, cmd->hint_root, | |
1008 | cblock, &hint_value); | |
1009 | if (r && r != -ENODATA) | |
1010 | return r; | |
1011 | } | |
1012 | ||
1013 | dirty = thunk->respect_dirty_flags ? (flags & M_DIRTY) : true; | |
1014 | r = thunk->fn(thunk->context, oblock, to_cblock(cblock), | |
1015 | dirty, le32_to_cpu(hint_value), thunk->hints_valid); | |
1016 | } | |
1017 | ||
1018 | return r; | |
1019 | } | |
1020 | ||
ea2dd8c1 MS |
1021 | static int __load_mappings(struct dm_cache_metadata *cmd, |
1022 | struct dm_cache_policy *policy, | |
c6b4fcba JT |
1023 | load_mapping_fn fn, void *context) |
1024 | { | |
1025 | struct thunk thunk; | |
1026 | ||
1027 | thunk.fn = fn; | |
1028 | thunk.context = context; | |
1029 | ||
1030 | thunk.cmd = cmd; | |
1031 | thunk.respect_dirty_flags = cmd->clean_when_opened; | |
ea2dd8c1 | 1032 | thunk.hints_valid = hints_array_available(cmd, policy); |
c6b4fcba JT |
1033 | |
1034 | return dm_array_walk(&cmd->info, cmd->root, __load_mapping, &thunk); | |
1035 | } | |
1036 | ||
ea2dd8c1 MS |
1037 | int dm_cache_load_mappings(struct dm_cache_metadata *cmd, |
1038 | struct dm_cache_policy *policy, | |
c6b4fcba JT |
1039 | load_mapping_fn fn, void *context) |
1040 | { | |
1041 | int r; | |
1042 | ||
1043 | down_read(&cmd->root_lock); | |
ea2dd8c1 | 1044 | r = __load_mappings(cmd, policy, fn, context); |
c6b4fcba JT |
1045 | up_read(&cmd->root_lock); |
1046 | ||
1047 | return r; | |
1048 | } | |
1049 | ||
1050 | static int __dump_mapping(void *context, uint64_t cblock, void *leaf) | |
1051 | { | |
1052 | int r = 0; | |
1053 | __le64 value; | |
1054 | dm_oblock_t oblock; | |
1055 | unsigned flags; | |
1056 | ||
1057 | memcpy(&value, leaf, sizeof(value)); | |
1058 | unpack_value(value, &oblock, &flags); | |
1059 | ||
1060 | return r; | |
1061 | } | |
1062 | ||
1063 | static int __dump_mappings(struct dm_cache_metadata *cmd) | |
1064 | { | |
1065 | return dm_array_walk(&cmd->info, cmd->root, __dump_mapping, NULL); | |
1066 | } | |
1067 | ||
1068 | void dm_cache_dump(struct dm_cache_metadata *cmd) | |
1069 | { | |
1070 | down_read(&cmd->root_lock); | |
1071 | __dump_mappings(cmd); | |
1072 | up_read(&cmd->root_lock); | |
1073 | } | |
1074 | ||
1075 | int dm_cache_changed_this_transaction(struct dm_cache_metadata *cmd) | |
1076 | { | |
1077 | int r; | |
1078 | ||
1079 | down_read(&cmd->root_lock); | |
1080 | r = cmd->changed; | |
1081 | up_read(&cmd->root_lock); | |
1082 | ||
1083 | return r; | |
1084 | } | |
1085 | ||
1086 | static int __dirty(struct dm_cache_metadata *cmd, dm_cblock_t cblock, bool dirty) | |
1087 | { | |
1088 | int r; | |
1089 | unsigned flags; | |
1090 | dm_oblock_t oblock; | |
1091 | __le64 value; | |
1092 | ||
1093 | r = dm_array_get_value(&cmd->info, cmd->root, from_cblock(cblock), &value); | |
1094 | if (r) | |
1095 | return r; | |
1096 | ||
1097 | unpack_value(value, &oblock, &flags); | |
1098 | ||
1099 | if (((flags & M_DIRTY) && dirty) || (!(flags & M_DIRTY) && !dirty)) | |
1100 | /* nothing to be done */ | |
1101 | return 0; | |
1102 | ||
79ed9caf | 1103 | value = pack_value(oblock, (flags & ~M_DIRTY) | (dirty ? M_DIRTY : 0)); |
c6b4fcba JT |
1104 | __dm_bless_for_disk(&value); |
1105 | ||
1106 | r = dm_array_set_value(&cmd->info, cmd->root, from_cblock(cblock), | |
1107 | &value, &cmd->root); | |
1108 | if (r) | |
1109 | return r; | |
1110 | ||
1111 | cmd->changed = true; | |
1112 | return 0; | |
1113 | ||
1114 | } | |
1115 | ||
1116 | int dm_cache_set_dirty(struct dm_cache_metadata *cmd, | |
1117 | dm_cblock_t cblock, bool dirty) | |
1118 | { | |
1119 | int r; | |
1120 | ||
1121 | down_write(&cmd->root_lock); | |
1122 | r = __dirty(cmd, cblock, dirty); | |
1123 | up_write(&cmd->root_lock); | |
1124 | ||
1125 | return r; | |
1126 | } | |
1127 | ||
1128 | void dm_cache_metadata_get_stats(struct dm_cache_metadata *cmd, | |
1129 | struct dm_cache_statistics *stats) | |
1130 | { | |
1131 | down_read(&cmd->root_lock); | |
8c5008fa | 1132 | *stats = cmd->stats; |
c6b4fcba JT |
1133 | up_read(&cmd->root_lock); |
1134 | } | |
1135 | ||
1136 | void dm_cache_metadata_set_stats(struct dm_cache_metadata *cmd, | |
1137 | struct dm_cache_statistics *stats) | |
1138 | { | |
1139 | down_write(&cmd->root_lock); | |
8c5008fa | 1140 | cmd->stats = *stats; |
c6b4fcba JT |
1141 | up_write(&cmd->root_lock); |
1142 | } | |
1143 | ||
1144 | int dm_cache_commit(struct dm_cache_metadata *cmd, bool clean_shutdown) | |
1145 | { | |
1146 | int r; | |
1147 | flags_mutator mutator = (clean_shutdown ? set_clean_shutdown : | |
1148 | clear_clean_shutdown); | |
1149 | ||
1150 | down_write(&cmd->root_lock); | |
1151 | r = __commit_transaction(cmd, mutator); | |
1152 | if (r) | |
1153 | goto out; | |
1154 | ||
1155 | r = __begin_transaction(cmd); | |
1156 | ||
1157 | out: | |
1158 | up_write(&cmd->root_lock); | |
1159 | return r; | |
1160 | } | |
1161 | ||
1162 | int dm_cache_get_free_metadata_block_count(struct dm_cache_metadata *cmd, | |
1163 | dm_block_t *result) | |
1164 | { | |
1165 | int r = -EINVAL; | |
1166 | ||
1167 | down_read(&cmd->root_lock); | |
1168 | r = dm_sm_get_nr_free(cmd->metadata_sm, result); | |
1169 | up_read(&cmd->root_lock); | |
1170 | ||
1171 | return r; | |
1172 | } | |
1173 | ||
1174 | int dm_cache_get_metadata_dev_size(struct dm_cache_metadata *cmd, | |
1175 | dm_block_t *result) | |
1176 | { | |
1177 | int r = -EINVAL; | |
1178 | ||
1179 | down_read(&cmd->root_lock); | |
1180 | r = dm_sm_get_nr_blocks(cmd->metadata_sm, result); | |
1181 | up_read(&cmd->root_lock); | |
1182 | ||
1183 | return r; | |
1184 | } | |
1185 | ||
1186 | /*----------------------------------------------------------------*/ | |
1187 | ||
1188 | static int begin_hints(struct dm_cache_metadata *cmd, struct dm_cache_policy *policy) | |
1189 | { | |
1190 | int r; | |
1191 | __le32 value; | |
1192 | size_t hint_size; | |
1193 | const char *policy_name = dm_cache_policy_get_name(policy); | |
4e7f506f | 1194 | const unsigned *policy_version = dm_cache_policy_get_version(policy); |
c6b4fcba JT |
1195 | |
1196 | if (!policy_name[0] || | |
1197 | (strlen(policy_name) > sizeof(cmd->policy_name) - 1)) | |
1198 | return -EINVAL; | |
1199 | ||
ea2dd8c1 | 1200 | if (!policy_unchanged(cmd, policy)) { |
c6b4fcba | 1201 | strncpy(cmd->policy_name, policy_name, sizeof(cmd->policy_name)); |
4e7f506f | 1202 | memcpy(cmd->policy_version, policy_version, sizeof(cmd->policy_version)); |
c6b4fcba JT |
1203 | |
1204 | hint_size = dm_cache_policy_get_hint_size(policy); | |
1205 | if (!hint_size) | |
1206 | return 0; /* short-circuit hints initialization */ | |
1207 | cmd->policy_hint_size = hint_size; | |
1208 | ||
1209 | if (cmd->hint_root) { | |
1210 | r = dm_array_del(&cmd->hint_info, cmd->hint_root); | |
1211 | if (r) | |
1212 | return r; | |
1213 | } | |
1214 | ||
1215 | r = dm_array_empty(&cmd->hint_info, &cmd->hint_root); | |
1216 | if (r) | |
1217 | return r; | |
1218 | ||
1219 | value = cpu_to_le32(0); | |
1220 | __dm_bless_for_disk(&value); | |
1221 | r = dm_array_resize(&cmd->hint_info, cmd->hint_root, 0, | |
1222 | from_cblock(cmd->cache_blocks), | |
1223 | &value, &cmd->hint_root); | |
1224 | if (r) | |
1225 | return r; | |
1226 | } | |
1227 | ||
1228 | return 0; | |
1229 | } | |
1230 | ||
1231 | int dm_cache_begin_hints(struct dm_cache_metadata *cmd, struct dm_cache_policy *policy) | |
1232 | { | |
1233 | int r; | |
1234 | ||
1235 | down_write(&cmd->root_lock); | |
1236 | r = begin_hints(cmd, policy); | |
1237 | up_write(&cmd->root_lock); | |
1238 | ||
1239 | return r; | |
1240 | } | |
1241 | ||
1242 | static int save_hint(struct dm_cache_metadata *cmd, dm_cblock_t cblock, | |
1243 | uint32_t hint) | |
1244 | { | |
1245 | int r; | |
1246 | __le32 value = cpu_to_le32(hint); | |
1247 | __dm_bless_for_disk(&value); | |
1248 | ||
1249 | r = dm_array_set_value(&cmd->hint_info, cmd->hint_root, | |
1250 | from_cblock(cblock), &value, &cmd->hint_root); | |
1251 | cmd->changed = true; | |
1252 | ||
1253 | return r; | |
1254 | } | |
1255 | ||
1256 | int dm_cache_save_hint(struct dm_cache_metadata *cmd, dm_cblock_t cblock, | |
1257 | uint32_t hint) | |
1258 | { | |
1259 | int r; | |
1260 | ||
1261 | if (!hints_array_initialized(cmd)) | |
1262 | return 0; | |
1263 | ||
1264 | down_write(&cmd->root_lock); | |
1265 | r = save_hint(cmd, cblock, hint); | |
1266 | up_write(&cmd->root_lock); | |
1267 | ||
1268 | return r; | |
1269 | } | |
2ee57d58 JT |
1270 | |
1271 | int dm_cache_metadata_all_clean(struct dm_cache_metadata *cmd, bool *result) | |
1272 | { | |
1273 | return blocks_are_unmapped_or_clean(cmd, 0, cmd->cache_blocks, result); | |
1274 | } |