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)); |
895b47d7 | 333 | disk_super->metadata_block_size = cpu_to_le32(DM_CACHE_METADATA_BLOCK_SIZE); |
c6b4fcba JT |
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 | ||
048e5a07 MS |
428 | /* 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 | ||
c6b4fcba JT |
437 | 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 | ||
456 | bad: | |
457 | dm_bm_unlock(sblock); | |
458 | return r; | |
459 | } | |
460 | ||
461 | static int __open_or_format_metadata(struct dm_cache_metadata *cmd, | |
462 | bool format_device) | |
463 | { | |
dd8b0c20 JT |
464 | int r; |
465 | bool unformatted = false; | |
c6b4fcba JT |
466 | |
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 | ||
477 | static int __create_persistent_data_objects(struct dm_cache_metadata *cmd, | |
478 | bool may_format_device) | |
479 | { | |
480 | int r; | |
895b47d7 | 481 | cmd->bm = dm_block_manager_create(cmd->bdev, DM_CACHE_METADATA_BLOCK_SIZE << SECTOR_SHIFT, |
c6b4fcba JT |
482 | 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 | ||
496 | static 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 | ||
503 | typedef unsigned long (*flags_mutator)(unsigned long); | |
504 | ||
505 | static 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 | ||
512 | static unsigned long set_clean_shutdown(unsigned long flags) | |
513 | { | |
514 | set_bit(CLEAN_SHUTDOWN, &flags); | |
515 | return flags; | |
516 | } | |
517 | ||
518 | static unsigned long clear_clean_shutdown(unsigned long flags) | |
519 | { | |
520 | clear_bit(CLEAN_SHUTDOWN, &flags); | |
521 | return flags; | |
522 | } | |
523 | ||
524 | static 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); | |
64ab346a | 531 | cmd->discard_nr_blocks = to_oblock(le64_to_cpu(disk_super->discard_nr_blocks)); |
c6b4fcba JT |
532 | 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)); | |
4e7f506f MS |
535 | 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]); | |
c6b4fcba JT |
538 | 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 | */ | |
551 | static 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); | |
a9d45396 | 565 | dm_bm_unlock(sblock); |
c6b4fcba | 566 | |
a9d45396 | 567 | return dm_bm_flush(cmd->bm); |
c6b4fcba JT |
568 | } |
569 | ||
570 | static 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 | ||
591 | static int __commit_transaction(struct dm_cache_metadata *cmd, | |
592 | flags_mutator mutator) | |
593 | { | |
594 | int r; | |
c6b4fcba JT |
595 | 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 | ||
5a32083d JT |
612 | r = __save_sm_root(cmd); |
613 | if (r) | |
c6b4fcba JT |
614 | 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); | |
64ab346a | 629 | disk_super->discard_nr_blocks = cpu_to_le64(from_oblock(cmd->discard_nr_blocks)); |
c6b4fcba JT |
630 | 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)); | |
4e7f506f MS |
632 | 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]); | |
c6b4fcba JT |
635 | |
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); | |
5a32083d | 640 | __copy_sm_root(cmd, disk_super); |
c6b4fcba JT |
641 | |
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 | ||
654 | static __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 | ||
662 | static 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 | ||
672 | struct 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 | ||
708 | void dm_cache_metadata_close(struct dm_cache_metadata *cmd) | |
709 | { | |
710 | __destroy_persistent_data_objects(cmd); | |
711 | kfree(cmd); | |
712 | } | |
713 | ||
f494a9c6 JT |
714 | /* |
715 | * Checks that the given cache block is either unmapped or clean. | |
716 | */ | |
717 | static 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 | ||
737 | static 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 | ||
c6b4fcba JT |
761 | int dm_cache_resize(struct dm_cache_metadata *cmd, dm_cblock_t new_cache_size) |
762 | { | |
763 | int r; | |
f494a9c6 | 764 | bool clean; |
c6b4fcba JT |
765 | __le64 null_mapping = pack_value(0, 0); |
766 | ||
767 | down_write(&cmd->root_lock); | |
768 | __dm_bless_for_disk(&null_mapping); | |
f494a9c6 JT |
769 | |
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 | ||
c6b4fcba JT |
785 | 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; | |
f494a9c6 JT |
791 | |
792 | out: | |
c6b4fcba JT |
793 | up_write(&cmd->root_lock); |
794 | ||
795 | return r; | |
796 | } | |
797 | ||
798 | int dm_cache_discard_bitset_resize(struct dm_cache_metadata *cmd, | |
799 | sector_t discard_block_size, | |
64ab346a | 800 | dm_oblock_t new_nr_entries) |
c6b4fcba JT |
801 | { |
802 | int r; | |
803 | ||
804 | down_write(&cmd->root_lock); | |
805 | r = dm_bitset_resize(&cmd->discard_info, | |
806 | cmd->discard_root, | |
64ab346a HM |
807 | from_oblock(cmd->discard_nr_blocks), |
808 | from_oblock(new_nr_entries), | |
c6b4fcba JT |
809 | 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 | ||
64ab346a | 821 | static int __set_discard(struct dm_cache_metadata *cmd, dm_oblock_t b) |
c6b4fcba JT |
822 | { |
823 | return dm_bitset_set_bit(&cmd->discard_info, cmd->discard_root, | |
64ab346a | 824 | from_oblock(b), &cmd->discard_root); |
c6b4fcba JT |
825 | } |
826 | ||
64ab346a | 827 | static int __clear_discard(struct dm_cache_metadata *cmd, dm_oblock_t b) |
c6b4fcba JT |
828 | { |
829 | return dm_bitset_clear_bit(&cmd->discard_info, cmd->discard_root, | |
64ab346a | 830 | from_oblock(b), &cmd->discard_root); |
c6b4fcba JT |
831 | } |
832 | ||
64ab346a | 833 | static int __is_discarded(struct dm_cache_metadata *cmd, dm_oblock_t b, |
c6b4fcba JT |
834 | bool *is_discarded) |
835 | { | |
836 | return dm_bitset_test_bit(&cmd->discard_info, cmd->discard_root, | |
64ab346a | 837 | from_oblock(b), &cmd->discard_root, |
c6b4fcba JT |
838 | is_discarded); |
839 | } | |
840 | ||
841 | static int __discard(struct dm_cache_metadata *cmd, | |
64ab346a | 842 | dm_oblock_t dblock, bool discard) |
c6b4fcba JT |
843 | { |
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 | ||
854 | int dm_cache_set_discard(struct dm_cache_metadata *cmd, | |
64ab346a | 855 | dm_oblock_t dblock, bool discard) |
c6b4fcba JT |
856 | { |
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 | ||
866 | static 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 | ||
64ab346a HM |
873 | for (b = 0; b < from_oblock(cmd->discard_nr_blocks); b++) { |
874 | dm_oblock_t dblock = to_oblock(b); | |
c6b4fcba JT |
875 | |
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 | ||
891 | int 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 | ||
903 | dm_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 | ||
914 | static 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 | ||
929 | int 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 | ||
940 | static 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 | ||
956 | int 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 | ||
968 | struct 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 | ||
ea2dd8c1 MS |
977 | static 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 | ||
c6b4fcba JT |
1005 | static bool hints_array_initialized(struct dm_cache_metadata *cmd) |
1006 | { | |
1007 | return cmd->hint_root && cmd->policy_hint_size; | |
1008 | } | |
1009 | ||
1010 | static bool hints_array_available(struct dm_cache_metadata *cmd, | |
ea2dd8c1 | 1011 | struct dm_cache_policy *policy) |
c6b4fcba | 1012 | { |
ea2dd8c1 | 1013 | return cmd->clean_when_opened && policy_unchanged(cmd, policy) && |
c6b4fcba JT |
1014 | hints_array_initialized(cmd); |
1015 | } | |
1016 | ||
1017 | static 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 | ||
ea2dd8c1 MS |
1047 | static int __load_mappings(struct dm_cache_metadata *cmd, |
1048 | struct dm_cache_policy *policy, | |
c6b4fcba JT |
1049 | 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; | |
ea2dd8c1 | 1058 | thunk.hints_valid = hints_array_available(cmd, policy); |
c6b4fcba JT |
1059 | |
1060 | return dm_array_walk(&cmd->info, cmd->root, __load_mapping, &thunk); | |
1061 | } | |
1062 | ||
ea2dd8c1 MS |
1063 | int dm_cache_load_mappings(struct dm_cache_metadata *cmd, |
1064 | struct dm_cache_policy *policy, | |
c6b4fcba JT |
1065 | load_mapping_fn fn, void *context) |
1066 | { | |
1067 | int r; | |
1068 | ||
1069 | down_read(&cmd->root_lock); | |
ea2dd8c1 | 1070 | r = __load_mappings(cmd, policy, fn, context); |
c6b4fcba JT |
1071 | up_read(&cmd->root_lock); |
1072 | ||
1073 | return r; | |
1074 | } | |
1075 | ||
1076 | static 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 | ||
1089 | static int __dump_mappings(struct dm_cache_metadata *cmd) | |
1090 | { | |
1091 | return dm_array_walk(&cmd->info, cmd->root, __dump_mapping, NULL); | |
1092 | } | |
1093 | ||
1094 | void 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 | ||
1101 | int 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 | ||
1112 | static 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 | ||
79ed9caf | 1129 | value = pack_value(oblock, (flags & ~M_DIRTY) | (dirty ? M_DIRTY : 0)); |
c6b4fcba JT |
1130 | __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 | ||
1142 | int 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 | ||
1154 | void dm_cache_metadata_get_stats(struct dm_cache_metadata *cmd, | |
1155 | struct dm_cache_statistics *stats) | |
1156 | { | |
1157 | down_read(&cmd->root_lock); | |
8c5008fa | 1158 | *stats = cmd->stats; |
c6b4fcba JT |
1159 | up_read(&cmd->root_lock); |
1160 | } | |
1161 | ||
1162 | void dm_cache_metadata_set_stats(struct dm_cache_metadata *cmd, | |
1163 | struct dm_cache_statistics *stats) | |
1164 | { | |
1165 | down_write(&cmd->root_lock); | |
8c5008fa | 1166 | cmd->stats = *stats; |
c6b4fcba JT |
1167 | up_write(&cmd->root_lock); |
1168 | } | |
1169 | ||
1170 | int 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 | ||
1183 | out: | |
1184 | up_write(&cmd->root_lock); | |
1185 | return r; | |
1186 | } | |
1187 | ||
1188 | int 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 | ||
1200 | int 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 | ||
1214 | static 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); | |
4e7f506f | 1220 | const unsigned *policy_version = dm_cache_policy_get_version(policy); |
c6b4fcba JT |
1221 | |
1222 | if (!policy_name[0] || | |
1223 | (strlen(policy_name) > sizeof(cmd->policy_name) - 1)) | |
1224 | return -EINVAL; | |
1225 | ||
ea2dd8c1 | 1226 | if (!policy_unchanged(cmd, policy)) { |
c6b4fcba | 1227 | strncpy(cmd->policy_name, policy_name, sizeof(cmd->policy_name)); |
4e7f506f | 1228 | memcpy(cmd->policy_version, policy_version, sizeof(cmd->policy_version)); |
c6b4fcba JT |
1229 | |
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 | ||
0596661f | 1257 | static int save_hint(void *context, dm_cblock_t cblock, dm_oblock_t oblock, uint32_t hint) |
c6b4fcba | 1258 | { |
0596661f JT |
1259 | struct dm_cache_metadata *cmd = context; |
1260 | __le32 value = cpu_to_le32(hint); | |
c6b4fcba JT |
1261 | int r; |
1262 | ||
c6b4fcba JT |
1263 | __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 | ||
0596661f | 1272 | static int write_hints(struct dm_cache_metadata *cmd, struct dm_cache_policy *policy) |
c6b4fcba JT |
1273 | { |
1274 | int r; | |
1275 | ||
0596661f JT |
1276 | 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 | ||
1285 | int dm_cache_write_hints(struct dm_cache_metadata *cmd, struct dm_cache_policy *policy) | |
1286 | { | |
1287 | int r; | |
c6b4fcba JT |
1288 | |
1289 | down_write(&cmd->root_lock); | |
0596661f | 1290 | r = write_hints(cmd, policy); |
c6b4fcba JT |
1291 | up_write(&cmd->root_lock); |
1292 | ||
1293 | return r; | |
1294 | } | |
2ee57d58 JT |
1295 | |
1296 | int 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 | } |