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; | |
5a32083d JT |
123 | |
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]; | |
c6b4fcba JT |
129 | }; |
130 | ||
131 | /*------------------------------------------------------------------- | |
132 | * superblock validator | |
133 | *-----------------------------------------------------------------*/ | |
134 | ||
135 | #define SUPERBLOCK_CSUM_XOR 9031977 | |
136 | ||
137 | static 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 | ||
53d49819 JT |
149 | static 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 | ||
c6b4fcba JT |
161 | static 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 | ||
53d49819 | 191 | return check_metadata_version(disk_super); |
c6b4fcba JT |
192 | } |
193 | ||
194 | static 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 | ||
202 | static 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 | ||
209 | static 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 | ||
216 | static 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 | ||
dd8b0c20 | 225 | static int __superblock_all_zeroes(struct dm_block_manager *bm, bool *result) |
c6b4fcba JT |
226 | { |
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); | |
dd8b0c20 | 241 | *result = true; |
c6b4fcba JT |
242 | for (i = 0; i < sb_block_size; i++) { |
243 | if (data_le[i] != zero) { | |
dd8b0c20 | 244 | *result = false; |
c6b4fcba JT |
245 | break; |
246 | } | |
247 | } | |
248 | ||
249 | return dm_bm_unlock(b); | |
250 | } | |
251 | ||
252 | static 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 | ||
5a32083d JT |
269 | static 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 | ||
282 | static 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 | ||
c6b4fcba JT |
290 | static int __write_initial_superblock(struct dm_cache_metadata *cmd) |
291 | { | |
292 | int r; | |
293 | struct dm_block *sblock; | |
c6b4fcba JT |
294 | 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 | ||
5a32083d | 301 | r = dm_tm_pre_commit(cmd->tm); |
c6b4fcba JT |
302 | if (r < 0) |
303 | return r; | |
304 | ||
5a32083d JT |
305 | /* |
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) | |
c6b4fcba JT |
311 | 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); | |
53d49819 | 321 | disk_super->version = cpu_to_le32(MAX_CACHE_VERSION); |
4e7f506f MS |
322 | memset(disk_super->policy_name, 0, sizeof(disk_super->policy_name)); |
323 | memset(disk_super->policy_version, 0, sizeof(disk_super->policy_version)); | |
c6b4fcba JT |
324 | disk_super->policy_hint_size = 0; |
325 | ||
5a32083d | 326 | __copy_sm_root(cmd, disk_super); |
c6b4fcba JT |
327 | |
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); | |
64ab346a | 332 | disk_super->discard_nr_blocks = cpu_to_le64(from_oblock(cmd->discard_nr_blocks)); |
c6b4fcba JT |
333 | disk_super->metadata_block_size = cpu_to_le32(DM_CACHE_METADATA_BLOCK_SIZE >> SECTOR_SHIFT); |
334 | disk_super->data_block_size = cpu_to_le32(cmd->data_block_size); | |
335 | disk_super->cache_blocks = cpu_to_le32(0); | |
c6b4fcba JT |
336 | |
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); | |
c6b4fcba JT |
343 | } |
344 | ||
345 | static 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 | ||
378 | bad: | |
379 | dm_tm_destroy(cmd->tm); | |
380 | dm_sm_destroy(cmd->metadata_sm); | |
381 | ||
382 | return r; | |
383 | } | |
384 | ||
385 | static 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 | ||
413 | static 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 | ||
428 | r = __check_incompat_features(disk_super, cmd); | |
429 | if (r < 0) | |
430 | goto bad; | |
431 | ||
432 | r = dm_tm_open_with_sm(cmd->bm, CACHE_SUPERBLOCK_LOCATION, | |
433 | disk_super->metadata_space_map_root, | |
434 | sizeof(disk_super->metadata_space_map_root), | |
435 | &cmd->tm, &cmd->metadata_sm); | |
436 | if (r < 0) { | |
437 | DMERR("tm_open_with_sm failed"); | |
438 | goto bad; | |
439 | } | |
440 | ||
441 | __setup_mapping_info(cmd); | |
442 | dm_disk_bitset_init(cmd->tm, &cmd->discard_info); | |
443 | sb_flags = le32_to_cpu(disk_super->flags); | |
444 | cmd->clean_when_opened = test_bit(CLEAN_SHUTDOWN, &sb_flags); | |
445 | return dm_bm_unlock(sblock); | |
446 | ||
447 | bad: | |
448 | dm_bm_unlock(sblock); | |
449 | return r; | |
450 | } | |
451 | ||
452 | static int __open_or_format_metadata(struct dm_cache_metadata *cmd, | |
453 | bool format_device) | |
454 | { | |
dd8b0c20 JT |
455 | int r; |
456 | bool unformatted = false; | |
c6b4fcba JT |
457 | |
458 | r = __superblock_all_zeroes(cmd->bm, &unformatted); | |
459 | if (r) | |
460 | return r; | |
461 | ||
462 | if (unformatted) | |
463 | return format_device ? __format_metadata(cmd) : -EPERM; | |
464 | ||
465 | return __open_metadata(cmd); | |
466 | } | |
467 | ||
468 | static int __create_persistent_data_objects(struct dm_cache_metadata *cmd, | |
469 | bool may_format_device) | |
470 | { | |
471 | int r; | |
472 | cmd->bm = dm_block_manager_create(cmd->bdev, DM_CACHE_METADATA_BLOCK_SIZE, | |
473 | CACHE_METADATA_CACHE_SIZE, | |
474 | CACHE_MAX_CONCURRENT_LOCKS); | |
475 | if (IS_ERR(cmd->bm)) { | |
476 | DMERR("could not create block manager"); | |
477 | return PTR_ERR(cmd->bm); | |
478 | } | |
479 | ||
480 | r = __open_or_format_metadata(cmd, may_format_device); | |
481 | if (r) | |
482 | dm_block_manager_destroy(cmd->bm); | |
483 | ||
484 | return r; | |
485 | } | |
486 | ||
487 | static void __destroy_persistent_data_objects(struct dm_cache_metadata *cmd) | |
488 | { | |
489 | dm_sm_destroy(cmd->metadata_sm); | |
490 | dm_tm_destroy(cmd->tm); | |
491 | dm_block_manager_destroy(cmd->bm); | |
492 | } | |
493 | ||
494 | typedef unsigned long (*flags_mutator)(unsigned long); | |
495 | ||
496 | static void update_flags(struct cache_disk_superblock *disk_super, | |
497 | flags_mutator mutator) | |
498 | { | |
499 | uint32_t sb_flags = mutator(le32_to_cpu(disk_super->flags)); | |
500 | disk_super->flags = cpu_to_le32(sb_flags); | |
501 | } | |
502 | ||
503 | static unsigned long set_clean_shutdown(unsigned long flags) | |
504 | { | |
505 | set_bit(CLEAN_SHUTDOWN, &flags); | |
506 | return flags; | |
507 | } | |
508 | ||
509 | static unsigned long clear_clean_shutdown(unsigned long flags) | |
510 | { | |
511 | clear_bit(CLEAN_SHUTDOWN, &flags); | |
512 | return flags; | |
513 | } | |
514 | ||
515 | static void read_superblock_fields(struct dm_cache_metadata *cmd, | |
516 | struct cache_disk_superblock *disk_super) | |
517 | { | |
518 | cmd->root = le64_to_cpu(disk_super->mapping_root); | |
519 | cmd->hint_root = le64_to_cpu(disk_super->hint_root); | |
520 | cmd->discard_root = le64_to_cpu(disk_super->discard_root); | |
521 | cmd->discard_block_size = le64_to_cpu(disk_super->discard_block_size); | |
64ab346a | 522 | cmd->discard_nr_blocks = to_oblock(le64_to_cpu(disk_super->discard_nr_blocks)); |
c6b4fcba JT |
523 | cmd->data_block_size = le32_to_cpu(disk_super->data_block_size); |
524 | cmd->cache_blocks = to_cblock(le32_to_cpu(disk_super->cache_blocks)); | |
525 | strncpy(cmd->policy_name, disk_super->policy_name, sizeof(cmd->policy_name)); | |
4e7f506f MS |
526 | cmd->policy_version[0] = le32_to_cpu(disk_super->policy_version[0]); |
527 | cmd->policy_version[1] = le32_to_cpu(disk_super->policy_version[1]); | |
528 | cmd->policy_version[2] = le32_to_cpu(disk_super->policy_version[2]); | |
c6b4fcba JT |
529 | cmd->policy_hint_size = le32_to_cpu(disk_super->policy_hint_size); |
530 | ||
531 | cmd->stats.read_hits = le32_to_cpu(disk_super->read_hits); | |
532 | cmd->stats.read_misses = le32_to_cpu(disk_super->read_misses); | |
533 | cmd->stats.write_hits = le32_to_cpu(disk_super->write_hits); | |
534 | cmd->stats.write_misses = le32_to_cpu(disk_super->write_misses); | |
535 | ||
536 | cmd->changed = false; | |
537 | } | |
538 | ||
539 | /* | |
540 | * The mutator updates the superblock flags. | |
541 | */ | |
542 | static int __begin_transaction_flags(struct dm_cache_metadata *cmd, | |
543 | flags_mutator mutator) | |
544 | { | |
545 | int r; | |
546 | struct cache_disk_superblock *disk_super; | |
547 | struct dm_block *sblock; | |
548 | ||
549 | r = superblock_lock(cmd, &sblock); | |
550 | if (r) | |
551 | return r; | |
552 | ||
553 | disk_super = dm_block_data(sblock); | |
554 | update_flags(disk_super, mutator); | |
555 | read_superblock_fields(cmd, disk_super); | |
a9d45396 | 556 | dm_bm_unlock(sblock); |
c6b4fcba | 557 | |
a9d45396 | 558 | return dm_bm_flush(cmd->bm); |
c6b4fcba JT |
559 | } |
560 | ||
561 | static int __begin_transaction(struct dm_cache_metadata *cmd) | |
562 | { | |
563 | int r; | |
564 | struct cache_disk_superblock *disk_super; | |
565 | struct dm_block *sblock; | |
566 | ||
567 | /* | |
568 | * We re-read the superblock every time. Shouldn't need to do this | |
569 | * really. | |
570 | */ | |
571 | r = superblock_read_lock(cmd, &sblock); | |
572 | if (r) | |
573 | return r; | |
574 | ||
575 | disk_super = dm_block_data(sblock); | |
576 | read_superblock_fields(cmd, disk_super); | |
577 | dm_bm_unlock(sblock); | |
578 | ||
579 | return 0; | |
580 | } | |
581 | ||
582 | static int __commit_transaction(struct dm_cache_metadata *cmd, | |
583 | flags_mutator mutator) | |
584 | { | |
585 | int r; | |
c6b4fcba JT |
586 | struct cache_disk_superblock *disk_super; |
587 | struct dm_block *sblock; | |
588 | ||
589 | /* | |
590 | * We need to know if the cache_disk_superblock exceeds a 512-byte sector. | |
591 | */ | |
592 | BUILD_BUG_ON(sizeof(struct cache_disk_superblock) > 512); | |
593 | ||
594 | r = dm_bitset_flush(&cmd->discard_info, cmd->discard_root, | |
595 | &cmd->discard_root); | |
596 | if (r) | |
597 | return r; | |
598 | ||
599 | r = dm_tm_pre_commit(cmd->tm); | |
600 | if (r < 0) | |
601 | return r; | |
602 | ||
5a32083d JT |
603 | r = __save_sm_root(cmd); |
604 | if (r) | |
c6b4fcba JT |
605 | return r; |
606 | ||
607 | r = superblock_lock(cmd, &sblock); | |
608 | if (r) | |
609 | return r; | |
610 | ||
611 | disk_super = dm_block_data(sblock); | |
612 | ||
613 | if (mutator) | |
614 | update_flags(disk_super, mutator); | |
615 | ||
616 | disk_super->mapping_root = cpu_to_le64(cmd->root); | |
617 | disk_super->hint_root = cpu_to_le64(cmd->hint_root); | |
618 | disk_super->discard_root = cpu_to_le64(cmd->discard_root); | |
619 | disk_super->discard_block_size = cpu_to_le64(cmd->discard_block_size); | |
64ab346a | 620 | disk_super->discard_nr_blocks = cpu_to_le64(from_oblock(cmd->discard_nr_blocks)); |
c6b4fcba JT |
621 | disk_super->cache_blocks = cpu_to_le32(from_cblock(cmd->cache_blocks)); |
622 | strncpy(disk_super->policy_name, cmd->policy_name, sizeof(disk_super->policy_name)); | |
4e7f506f MS |
623 | disk_super->policy_version[0] = cpu_to_le32(cmd->policy_version[0]); |
624 | disk_super->policy_version[1] = cpu_to_le32(cmd->policy_version[1]); | |
625 | disk_super->policy_version[2] = cpu_to_le32(cmd->policy_version[2]); | |
c6b4fcba JT |
626 | |
627 | disk_super->read_hits = cpu_to_le32(cmd->stats.read_hits); | |
628 | disk_super->read_misses = cpu_to_le32(cmd->stats.read_misses); | |
629 | disk_super->write_hits = cpu_to_le32(cmd->stats.write_hits); | |
630 | disk_super->write_misses = cpu_to_le32(cmd->stats.write_misses); | |
5a32083d | 631 | __copy_sm_root(cmd, disk_super); |
c6b4fcba JT |
632 | |
633 | return dm_tm_commit(cmd->tm, sblock); | |
634 | } | |
635 | ||
636 | /*----------------------------------------------------------------*/ | |
637 | ||
638 | /* | |
639 | * The mappings are held in a dm-array that has 64-bit values stored in | |
640 | * little-endian format. The index is the cblock, the high 48bits of the | |
641 | * value are the oblock and the low 16 bit the flags. | |
642 | */ | |
643 | #define FLAGS_MASK ((1 << 16) - 1) | |
644 | ||
645 | static __le64 pack_value(dm_oblock_t block, unsigned flags) | |
646 | { | |
647 | uint64_t value = from_oblock(block); | |
648 | value <<= 16; | |
649 | value = value | (flags & FLAGS_MASK); | |
650 | return cpu_to_le64(value); | |
651 | } | |
652 | ||
653 | static void unpack_value(__le64 value_le, dm_oblock_t *block, unsigned *flags) | |
654 | { | |
655 | uint64_t value = le64_to_cpu(value_le); | |
656 | uint64_t b = value >> 16; | |
657 | *block = to_oblock(b); | |
658 | *flags = value & FLAGS_MASK; | |
659 | } | |
660 | ||
661 | /*----------------------------------------------------------------*/ | |
662 | ||
663 | struct dm_cache_metadata *dm_cache_metadata_open(struct block_device *bdev, | |
664 | sector_t data_block_size, | |
665 | bool may_format_device, | |
666 | size_t policy_hint_size) | |
667 | { | |
668 | int r; | |
669 | struct dm_cache_metadata *cmd; | |
670 | ||
671 | cmd = kzalloc(sizeof(*cmd), GFP_KERNEL); | |
672 | if (!cmd) { | |
673 | DMERR("could not allocate metadata struct"); | |
674 | return NULL; | |
675 | } | |
676 | ||
677 | init_rwsem(&cmd->root_lock); | |
678 | cmd->bdev = bdev; | |
679 | cmd->data_block_size = data_block_size; | |
680 | cmd->cache_blocks = 0; | |
681 | cmd->policy_hint_size = policy_hint_size; | |
682 | cmd->changed = true; | |
683 | ||
684 | r = __create_persistent_data_objects(cmd, may_format_device); | |
685 | if (r) { | |
686 | kfree(cmd); | |
687 | return ERR_PTR(r); | |
688 | } | |
689 | ||
690 | r = __begin_transaction_flags(cmd, clear_clean_shutdown); | |
691 | if (r < 0) { | |
692 | dm_cache_metadata_close(cmd); | |
693 | return ERR_PTR(r); | |
694 | } | |
695 | ||
696 | return cmd; | |
697 | } | |
698 | ||
699 | void dm_cache_metadata_close(struct dm_cache_metadata *cmd) | |
700 | { | |
701 | __destroy_persistent_data_objects(cmd); | |
702 | kfree(cmd); | |
703 | } | |
704 | ||
f494a9c6 JT |
705 | /* |
706 | * Checks that the given cache block is either unmapped or clean. | |
707 | */ | |
708 | static int block_unmapped_or_clean(struct dm_cache_metadata *cmd, dm_cblock_t b, | |
709 | bool *result) | |
710 | { | |
711 | int r; | |
712 | __le64 value; | |
713 | dm_oblock_t ob; | |
714 | unsigned flags; | |
715 | ||
716 | r = dm_array_get_value(&cmd->info, cmd->root, from_cblock(b), &value); | |
717 | if (r) { | |
718 | DMERR("block_unmapped_or_clean failed"); | |
719 | return r; | |
720 | } | |
721 | ||
722 | unpack_value(value, &ob, &flags); | |
723 | *result = !((flags & M_VALID) && (flags & M_DIRTY)); | |
724 | ||
725 | return 0; | |
726 | } | |
727 | ||
728 | static int blocks_are_unmapped_or_clean(struct dm_cache_metadata *cmd, | |
729 | dm_cblock_t begin, dm_cblock_t end, | |
730 | bool *result) | |
731 | { | |
732 | int r; | |
733 | *result = true; | |
734 | ||
735 | while (begin != end) { | |
736 | r = block_unmapped_or_clean(cmd, begin, result); | |
737 | if (r) | |
738 | return r; | |
739 | ||
740 | if (!*result) { | |
741 | DMERR("cache block %llu is dirty", | |
742 | (unsigned long long) from_cblock(begin)); | |
743 | return 0; | |
744 | } | |
745 | ||
746 | begin = to_cblock(from_cblock(begin) + 1); | |
747 | } | |
748 | ||
749 | return 0; | |
750 | } | |
751 | ||
c6b4fcba JT |
752 | int dm_cache_resize(struct dm_cache_metadata *cmd, dm_cblock_t new_cache_size) |
753 | { | |
754 | int r; | |
f494a9c6 | 755 | bool clean; |
c6b4fcba JT |
756 | __le64 null_mapping = pack_value(0, 0); |
757 | ||
758 | down_write(&cmd->root_lock); | |
759 | __dm_bless_for_disk(&null_mapping); | |
f494a9c6 JT |
760 | |
761 | if (from_cblock(new_cache_size) < from_cblock(cmd->cache_blocks)) { | |
762 | r = blocks_are_unmapped_or_clean(cmd, new_cache_size, cmd->cache_blocks, &clean); | |
763 | if (r) { | |
764 | __dm_unbless_for_disk(&null_mapping); | |
765 | goto out; | |
766 | } | |
767 | ||
768 | if (!clean) { | |
769 | DMERR("unable to shrink cache due to dirty blocks"); | |
770 | r = -EINVAL; | |
771 | __dm_unbless_for_disk(&null_mapping); | |
772 | goto out; | |
773 | } | |
774 | } | |
775 | ||
c6b4fcba JT |
776 | r = dm_array_resize(&cmd->info, cmd->root, from_cblock(cmd->cache_blocks), |
777 | from_cblock(new_cache_size), | |
778 | &null_mapping, &cmd->root); | |
779 | if (!r) | |
780 | cmd->cache_blocks = new_cache_size; | |
781 | cmd->changed = true; | |
f494a9c6 JT |
782 | |
783 | out: | |
c6b4fcba JT |
784 | up_write(&cmd->root_lock); |
785 | ||
786 | return r; | |
787 | } | |
788 | ||
789 | int dm_cache_discard_bitset_resize(struct dm_cache_metadata *cmd, | |
790 | sector_t discard_block_size, | |
64ab346a | 791 | dm_oblock_t new_nr_entries) |
c6b4fcba JT |
792 | { |
793 | int r; | |
794 | ||
795 | down_write(&cmd->root_lock); | |
796 | r = dm_bitset_resize(&cmd->discard_info, | |
797 | cmd->discard_root, | |
64ab346a HM |
798 | from_oblock(cmd->discard_nr_blocks), |
799 | from_oblock(new_nr_entries), | |
c6b4fcba JT |
800 | false, &cmd->discard_root); |
801 | if (!r) { | |
802 | cmd->discard_block_size = discard_block_size; | |
803 | cmd->discard_nr_blocks = new_nr_entries; | |
804 | } | |
805 | ||
806 | cmd->changed = true; | |
807 | up_write(&cmd->root_lock); | |
808 | ||
809 | return r; | |
810 | } | |
811 | ||
64ab346a | 812 | static int __set_discard(struct dm_cache_metadata *cmd, dm_oblock_t b) |
c6b4fcba JT |
813 | { |
814 | return dm_bitset_set_bit(&cmd->discard_info, cmd->discard_root, | |
64ab346a | 815 | from_oblock(b), &cmd->discard_root); |
c6b4fcba JT |
816 | } |
817 | ||
64ab346a | 818 | static int __clear_discard(struct dm_cache_metadata *cmd, dm_oblock_t b) |
c6b4fcba JT |
819 | { |
820 | return dm_bitset_clear_bit(&cmd->discard_info, cmd->discard_root, | |
64ab346a | 821 | from_oblock(b), &cmd->discard_root); |
c6b4fcba JT |
822 | } |
823 | ||
64ab346a | 824 | static int __is_discarded(struct dm_cache_metadata *cmd, dm_oblock_t b, |
c6b4fcba JT |
825 | bool *is_discarded) |
826 | { | |
827 | return dm_bitset_test_bit(&cmd->discard_info, cmd->discard_root, | |
64ab346a | 828 | from_oblock(b), &cmd->discard_root, |
c6b4fcba JT |
829 | is_discarded); |
830 | } | |
831 | ||
832 | static int __discard(struct dm_cache_metadata *cmd, | |
64ab346a | 833 | dm_oblock_t dblock, bool discard) |
c6b4fcba JT |
834 | { |
835 | int r; | |
836 | ||
837 | r = (discard ? __set_discard : __clear_discard)(cmd, dblock); | |
838 | if (r) | |
839 | return r; | |
840 | ||
841 | cmd->changed = true; | |
842 | return 0; | |
843 | } | |
844 | ||
845 | int dm_cache_set_discard(struct dm_cache_metadata *cmd, | |
64ab346a | 846 | dm_oblock_t dblock, bool discard) |
c6b4fcba JT |
847 | { |
848 | int r; | |
849 | ||
850 | down_write(&cmd->root_lock); | |
851 | r = __discard(cmd, dblock, discard); | |
852 | up_write(&cmd->root_lock); | |
853 | ||
854 | return r; | |
855 | } | |
856 | ||
857 | static int __load_discards(struct dm_cache_metadata *cmd, | |
858 | load_discard_fn fn, void *context) | |
859 | { | |
860 | int r = 0; | |
861 | dm_block_t b; | |
862 | bool discard; | |
863 | ||
64ab346a HM |
864 | for (b = 0; b < from_oblock(cmd->discard_nr_blocks); b++) { |
865 | dm_oblock_t dblock = to_oblock(b); | |
c6b4fcba JT |
866 | |
867 | if (cmd->clean_when_opened) { | |
868 | r = __is_discarded(cmd, dblock, &discard); | |
869 | if (r) | |
870 | return r; | |
871 | } else | |
872 | discard = false; | |
873 | ||
874 | r = fn(context, cmd->discard_block_size, dblock, discard); | |
875 | if (r) | |
876 | break; | |
877 | } | |
878 | ||
879 | return r; | |
880 | } | |
881 | ||
882 | int dm_cache_load_discards(struct dm_cache_metadata *cmd, | |
883 | load_discard_fn fn, void *context) | |
884 | { | |
885 | int r; | |
886 | ||
887 | down_read(&cmd->root_lock); | |
888 | r = __load_discards(cmd, fn, context); | |
889 | up_read(&cmd->root_lock); | |
890 | ||
891 | return r; | |
892 | } | |
893 | ||
894 | dm_cblock_t dm_cache_size(struct dm_cache_metadata *cmd) | |
895 | { | |
896 | dm_cblock_t r; | |
897 | ||
898 | down_read(&cmd->root_lock); | |
899 | r = cmd->cache_blocks; | |
900 | up_read(&cmd->root_lock); | |
901 | ||
902 | return r; | |
903 | } | |
904 | ||
905 | static int __remove(struct dm_cache_metadata *cmd, dm_cblock_t cblock) | |
906 | { | |
907 | int r; | |
908 | __le64 value = pack_value(0, 0); | |
909 | ||
910 | __dm_bless_for_disk(&value); | |
911 | r = dm_array_set_value(&cmd->info, cmd->root, from_cblock(cblock), | |
912 | &value, &cmd->root); | |
913 | if (r) | |
914 | return r; | |
915 | ||
916 | cmd->changed = true; | |
917 | return 0; | |
918 | } | |
919 | ||
920 | int dm_cache_remove_mapping(struct dm_cache_metadata *cmd, dm_cblock_t cblock) | |
921 | { | |
922 | int r; | |
923 | ||
924 | down_write(&cmd->root_lock); | |
925 | r = __remove(cmd, cblock); | |
926 | up_write(&cmd->root_lock); | |
927 | ||
928 | return r; | |
929 | } | |
930 | ||
931 | static int __insert(struct dm_cache_metadata *cmd, | |
932 | dm_cblock_t cblock, dm_oblock_t oblock) | |
933 | { | |
934 | int r; | |
935 | __le64 value = pack_value(oblock, M_VALID); | |
936 | __dm_bless_for_disk(&value); | |
937 | ||
938 | r = dm_array_set_value(&cmd->info, cmd->root, from_cblock(cblock), | |
939 | &value, &cmd->root); | |
940 | if (r) | |
941 | return r; | |
942 | ||
943 | cmd->changed = true; | |
944 | return 0; | |
945 | } | |
946 | ||
947 | int dm_cache_insert_mapping(struct dm_cache_metadata *cmd, | |
948 | dm_cblock_t cblock, dm_oblock_t oblock) | |
949 | { | |
950 | int r; | |
951 | ||
952 | down_write(&cmd->root_lock); | |
953 | r = __insert(cmd, cblock, oblock); | |
954 | up_write(&cmd->root_lock); | |
955 | ||
956 | return r; | |
957 | } | |
958 | ||
959 | struct thunk { | |
960 | load_mapping_fn fn; | |
961 | void *context; | |
962 | ||
963 | struct dm_cache_metadata *cmd; | |
964 | bool respect_dirty_flags; | |
965 | bool hints_valid; | |
966 | }; | |
967 | ||
ea2dd8c1 MS |
968 | static bool policy_unchanged(struct dm_cache_metadata *cmd, |
969 | struct dm_cache_policy *policy) | |
970 | { | |
971 | const char *policy_name = dm_cache_policy_get_name(policy); | |
972 | const unsigned *policy_version = dm_cache_policy_get_version(policy); | |
973 | size_t policy_hint_size = dm_cache_policy_get_hint_size(policy); | |
974 | ||
975 | /* | |
976 | * Ensure policy names match. | |
977 | */ | |
978 | if (strncmp(cmd->policy_name, policy_name, sizeof(cmd->policy_name))) | |
979 | return false; | |
980 | ||
981 | /* | |
982 | * Ensure policy major versions match. | |
983 | */ | |
984 | if (cmd->policy_version[0] != policy_version[0]) | |
985 | return false; | |
986 | ||
987 | /* | |
988 | * Ensure policy hint sizes match. | |
989 | */ | |
990 | if (cmd->policy_hint_size != policy_hint_size) | |
991 | return false; | |
992 | ||
993 | return true; | |
994 | } | |
995 | ||
c6b4fcba JT |
996 | static bool hints_array_initialized(struct dm_cache_metadata *cmd) |
997 | { | |
998 | return cmd->hint_root && cmd->policy_hint_size; | |
999 | } | |
1000 | ||
1001 | static bool hints_array_available(struct dm_cache_metadata *cmd, | |
ea2dd8c1 | 1002 | struct dm_cache_policy *policy) |
c6b4fcba | 1003 | { |
ea2dd8c1 | 1004 | return cmd->clean_when_opened && policy_unchanged(cmd, policy) && |
c6b4fcba JT |
1005 | hints_array_initialized(cmd); |
1006 | } | |
1007 | ||
1008 | static int __load_mapping(void *context, uint64_t cblock, void *leaf) | |
1009 | { | |
1010 | int r = 0; | |
1011 | bool dirty; | |
1012 | __le64 value; | |
1013 | __le32 hint_value = 0; | |
1014 | dm_oblock_t oblock; | |
1015 | unsigned flags; | |
1016 | struct thunk *thunk = context; | |
1017 | struct dm_cache_metadata *cmd = thunk->cmd; | |
1018 | ||
1019 | memcpy(&value, leaf, sizeof(value)); | |
1020 | unpack_value(value, &oblock, &flags); | |
1021 | ||
1022 | if (flags & M_VALID) { | |
1023 | if (thunk->hints_valid) { | |
1024 | r = dm_array_get_value(&cmd->hint_info, cmd->hint_root, | |
1025 | cblock, &hint_value); | |
1026 | if (r && r != -ENODATA) | |
1027 | return r; | |
1028 | } | |
1029 | ||
1030 | dirty = thunk->respect_dirty_flags ? (flags & M_DIRTY) : true; | |
1031 | r = thunk->fn(thunk->context, oblock, to_cblock(cblock), | |
1032 | dirty, le32_to_cpu(hint_value), thunk->hints_valid); | |
1033 | } | |
1034 | ||
1035 | return r; | |
1036 | } | |
1037 | ||
ea2dd8c1 MS |
1038 | static int __load_mappings(struct dm_cache_metadata *cmd, |
1039 | struct dm_cache_policy *policy, | |
c6b4fcba JT |
1040 | load_mapping_fn fn, void *context) |
1041 | { | |
1042 | struct thunk thunk; | |
1043 | ||
1044 | thunk.fn = fn; | |
1045 | thunk.context = context; | |
1046 | ||
1047 | thunk.cmd = cmd; | |
1048 | thunk.respect_dirty_flags = cmd->clean_when_opened; | |
ea2dd8c1 | 1049 | thunk.hints_valid = hints_array_available(cmd, policy); |
c6b4fcba JT |
1050 | |
1051 | return dm_array_walk(&cmd->info, cmd->root, __load_mapping, &thunk); | |
1052 | } | |
1053 | ||
ea2dd8c1 MS |
1054 | int dm_cache_load_mappings(struct dm_cache_metadata *cmd, |
1055 | struct dm_cache_policy *policy, | |
c6b4fcba JT |
1056 | load_mapping_fn fn, void *context) |
1057 | { | |
1058 | int r; | |
1059 | ||
1060 | down_read(&cmd->root_lock); | |
ea2dd8c1 | 1061 | r = __load_mappings(cmd, policy, fn, context); |
c6b4fcba JT |
1062 | up_read(&cmd->root_lock); |
1063 | ||
1064 | return r; | |
1065 | } | |
1066 | ||
1067 | static int __dump_mapping(void *context, uint64_t cblock, void *leaf) | |
1068 | { | |
1069 | int r = 0; | |
1070 | __le64 value; | |
1071 | dm_oblock_t oblock; | |
1072 | unsigned flags; | |
1073 | ||
1074 | memcpy(&value, leaf, sizeof(value)); | |
1075 | unpack_value(value, &oblock, &flags); | |
1076 | ||
1077 | return r; | |
1078 | } | |
1079 | ||
1080 | static int __dump_mappings(struct dm_cache_metadata *cmd) | |
1081 | { | |
1082 | return dm_array_walk(&cmd->info, cmd->root, __dump_mapping, NULL); | |
1083 | } | |
1084 | ||
1085 | void dm_cache_dump(struct dm_cache_metadata *cmd) | |
1086 | { | |
1087 | down_read(&cmd->root_lock); | |
1088 | __dump_mappings(cmd); | |
1089 | up_read(&cmd->root_lock); | |
1090 | } | |
1091 | ||
1092 | int dm_cache_changed_this_transaction(struct dm_cache_metadata *cmd) | |
1093 | { | |
1094 | int r; | |
1095 | ||
1096 | down_read(&cmd->root_lock); | |
1097 | r = cmd->changed; | |
1098 | up_read(&cmd->root_lock); | |
1099 | ||
1100 | return r; | |
1101 | } | |
1102 | ||
1103 | static int __dirty(struct dm_cache_metadata *cmd, dm_cblock_t cblock, bool dirty) | |
1104 | { | |
1105 | int r; | |
1106 | unsigned flags; | |
1107 | dm_oblock_t oblock; | |
1108 | __le64 value; | |
1109 | ||
1110 | r = dm_array_get_value(&cmd->info, cmd->root, from_cblock(cblock), &value); | |
1111 | if (r) | |
1112 | return r; | |
1113 | ||
1114 | unpack_value(value, &oblock, &flags); | |
1115 | ||
1116 | if (((flags & M_DIRTY) && dirty) || (!(flags & M_DIRTY) && !dirty)) | |
1117 | /* nothing to be done */ | |
1118 | return 0; | |
1119 | ||
79ed9caf | 1120 | value = pack_value(oblock, (flags & ~M_DIRTY) | (dirty ? M_DIRTY : 0)); |
c6b4fcba JT |
1121 | __dm_bless_for_disk(&value); |
1122 | ||
1123 | r = dm_array_set_value(&cmd->info, cmd->root, from_cblock(cblock), | |
1124 | &value, &cmd->root); | |
1125 | if (r) | |
1126 | return r; | |
1127 | ||
1128 | cmd->changed = true; | |
1129 | return 0; | |
1130 | ||
1131 | } | |
1132 | ||
1133 | int dm_cache_set_dirty(struct dm_cache_metadata *cmd, | |
1134 | dm_cblock_t cblock, bool dirty) | |
1135 | { | |
1136 | int r; | |
1137 | ||
1138 | down_write(&cmd->root_lock); | |
1139 | r = __dirty(cmd, cblock, dirty); | |
1140 | up_write(&cmd->root_lock); | |
1141 | ||
1142 | return r; | |
1143 | } | |
1144 | ||
1145 | void dm_cache_metadata_get_stats(struct dm_cache_metadata *cmd, | |
1146 | struct dm_cache_statistics *stats) | |
1147 | { | |
1148 | down_read(&cmd->root_lock); | |
8c5008fa | 1149 | *stats = cmd->stats; |
c6b4fcba JT |
1150 | up_read(&cmd->root_lock); |
1151 | } | |
1152 | ||
1153 | void dm_cache_metadata_set_stats(struct dm_cache_metadata *cmd, | |
1154 | struct dm_cache_statistics *stats) | |
1155 | { | |
1156 | down_write(&cmd->root_lock); | |
8c5008fa | 1157 | cmd->stats = *stats; |
c6b4fcba JT |
1158 | up_write(&cmd->root_lock); |
1159 | } | |
1160 | ||
1161 | int dm_cache_commit(struct dm_cache_metadata *cmd, bool clean_shutdown) | |
1162 | { | |
1163 | int r; | |
1164 | flags_mutator mutator = (clean_shutdown ? set_clean_shutdown : | |
1165 | clear_clean_shutdown); | |
1166 | ||
1167 | down_write(&cmd->root_lock); | |
1168 | r = __commit_transaction(cmd, mutator); | |
1169 | if (r) | |
1170 | goto out; | |
1171 | ||
1172 | r = __begin_transaction(cmd); | |
1173 | ||
1174 | out: | |
1175 | up_write(&cmd->root_lock); | |
1176 | return r; | |
1177 | } | |
1178 | ||
1179 | int dm_cache_get_free_metadata_block_count(struct dm_cache_metadata *cmd, | |
1180 | dm_block_t *result) | |
1181 | { | |
1182 | int r = -EINVAL; | |
1183 | ||
1184 | down_read(&cmd->root_lock); | |
1185 | r = dm_sm_get_nr_free(cmd->metadata_sm, result); | |
1186 | up_read(&cmd->root_lock); | |
1187 | ||
1188 | return r; | |
1189 | } | |
1190 | ||
1191 | int dm_cache_get_metadata_dev_size(struct dm_cache_metadata *cmd, | |
1192 | dm_block_t *result) | |
1193 | { | |
1194 | int r = -EINVAL; | |
1195 | ||
1196 | down_read(&cmd->root_lock); | |
1197 | r = dm_sm_get_nr_blocks(cmd->metadata_sm, result); | |
1198 | up_read(&cmd->root_lock); | |
1199 | ||
1200 | return r; | |
1201 | } | |
1202 | ||
1203 | /*----------------------------------------------------------------*/ | |
1204 | ||
1205 | static int begin_hints(struct dm_cache_metadata *cmd, struct dm_cache_policy *policy) | |
1206 | { | |
1207 | int r; | |
1208 | __le32 value; | |
1209 | size_t hint_size; | |
1210 | const char *policy_name = dm_cache_policy_get_name(policy); | |
4e7f506f | 1211 | const unsigned *policy_version = dm_cache_policy_get_version(policy); |
c6b4fcba JT |
1212 | |
1213 | if (!policy_name[0] || | |
1214 | (strlen(policy_name) > sizeof(cmd->policy_name) - 1)) | |
1215 | return -EINVAL; | |
1216 | ||
ea2dd8c1 | 1217 | if (!policy_unchanged(cmd, policy)) { |
c6b4fcba | 1218 | strncpy(cmd->policy_name, policy_name, sizeof(cmd->policy_name)); |
4e7f506f | 1219 | memcpy(cmd->policy_version, policy_version, sizeof(cmd->policy_version)); |
c6b4fcba JT |
1220 | |
1221 | hint_size = dm_cache_policy_get_hint_size(policy); | |
1222 | if (!hint_size) | |
1223 | return 0; /* short-circuit hints initialization */ | |
1224 | cmd->policy_hint_size = hint_size; | |
1225 | ||
1226 | if (cmd->hint_root) { | |
1227 | r = dm_array_del(&cmd->hint_info, cmd->hint_root); | |
1228 | if (r) | |
1229 | return r; | |
1230 | } | |
1231 | ||
1232 | r = dm_array_empty(&cmd->hint_info, &cmd->hint_root); | |
1233 | if (r) | |
1234 | return r; | |
1235 | ||
1236 | value = cpu_to_le32(0); | |
1237 | __dm_bless_for_disk(&value); | |
1238 | r = dm_array_resize(&cmd->hint_info, cmd->hint_root, 0, | |
1239 | from_cblock(cmd->cache_blocks), | |
1240 | &value, &cmd->hint_root); | |
1241 | if (r) | |
1242 | return r; | |
1243 | } | |
1244 | ||
1245 | return 0; | |
1246 | } | |
1247 | ||
0596661f | 1248 | static int save_hint(void *context, dm_cblock_t cblock, dm_oblock_t oblock, uint32_t hint) |
c6b4fcba | 1249 | { |
0596661f JT |
1250 | struct dm_cache_metadata *cmd = context; |
1251 | __le32 value = cpu_to_le32(hint); | |
c6b4fcba JT |
1252 | int r; |
1253 | ||
c6b4fcba JT |
1254 | __dm_bless_for_disk(&value); |
1255 | ||
1256 | r = dm_array_set_value(&cmd->hint_info, cmd->hint_root, | |
1257 | from_cblock(cblock), &value, &cmd->hint_root); | |
1258 | cmd->changed = true; | |
1259 | ||
1260 | return r; | |
1261 | } | |
1262 | ||
0596661f | 1263 | static int write_hints(struct dm_cache_metadata *cmd, struct dm_cache_policy *policy) |
c6b4fcba JT |
1264 | { |
1265 | int r; | |
1266 | ||
0596661f JT |
1267 | r = begin_hints(cmd, policy); |
1268 | if (r) { | |
1269 | DMERR("begin_hints failed"); | |
1270 | return r; | |
1271 | } | |
1272 | ||
1273 | return policy_walk_mappings(policy, save_hint, cmd); | |
1274 | } | |
1275 | ||
1276 | int dm_cache_write_hints(struct dm_cache_metadata *cmd, struct dm_cache_policy *policy) | |
1277 | { | |
1278 | int r; | |
c6b4fcba JT |
1279 | |
1280 | down_write(&cmd->root_lock); | |
0596661f | 1281 | r = write_hints(cmd, policy); |
c6b4fcba JT |
1282 | up_write(&cmd->root_lock); |
1283 | ||
1284 | return r; | |
1285 | } | |
2ee57d58 JT |
1286 | |
1287 | int dm_cache_metadata_all_clean(struct dm_cache_metadata *cmd, bool *result) | |
1288 | { | |
1289 | return blocks_are_unmapped_or_clean(cmd, 0, cmd->cache_blocks, result); | |
1290 | } |