Commit | Line | Data |
---|---|---|
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, | |
028ae9f7 JT |
42 | /* metadata must be checked using the tools */ |
43 | NEEDS_CHECK, | |
c6b4fcba JT |
44 | }; |
45 | ||
46 | /* | |
47 | * Each mapping from cache block -> origin block carries a set of flags. | |
48 | */ | |
49 | enum mapping_bits { | |
50 | /* | |
51 | * A valid mapping. Because we're using an array we clear this | |
52 | * flag for an non existant mapping. | |
53 | */ | |
54 | M_VALID = 1, | |
55 | ||
56 | /* | |
57 | * The data on the cache is different from that on the origin. | |
58 | */ | |
59 | M_DIRTY = 2 | |
60 | }; | |
61 | ||
62 | struct cache_disk_superblock { | |
63 | __le32 csum; | |
64 | __le32 flags; | |
65 | __le64 blocknr; | |
66 | ||
67 | __u8 uuid[16]; | |
68 | __le64 magic; | |
69 | __le32 version; | |
70 | ||
71 | __u8 policy_name[CACHE_POLICY_NAME_SIZE]; | |
72 | __le32 policy_hint_size; | |
73 | ||
74 | __u8 metadata_space_map_root[SPACE_MAP_ROOT_SIZE]; | |
75 | __le64 mapping_root; | |
76 | __le64 hint_root; | |
77 | ||
78 | __le64 discard_root; | |
79 | __le64 discard_block_size; | |
80 | __le64 discard_nr_blocks; | |
81 | ||
82 | __le32 data_block_size; | |
83 | __le32 metadata_block_size; | |
84 | __le32 cache_blocks; | |
85 | ||
86 | __le32 compat_flags; | |
87 | __le32 compat_ro_flags; | |
88 | __le32 incompat_flags; | |
89 | ||
90 | __le32 read_hits; | |
91 | __le32 read_misses; | |
92 | __le32 write_hits; | |
93 | __le32 write_misses; | |
4e7f506f MS |
94 | |
95 | __le32 policy_version[CACHE_POLICY_VERSION_SIZE]; | |
c6b4fcba JT |
96 | } __packed; |
97 | ||
98 | struct dm_cache_metadata { | |
9b1cc9f2 JT |
99 | atomic_t ref_count; |
100 | struct list_head list; | |
101 | ||
c6b4fcba JT |
102 | struct block_device *bdev; |
103 | struct dm_block_manager *bm; | |
104 | struct dm_space_map *metadata_sm; | |
105 | struct dm_transaction_manager *tm; | |
106 | ||
107 | struct dm_array_info info; | |
108 | struct dm_array_info hint_info; | |
109 | struct dm_disk_bitset discard_info; | |
110 | ||
111 | struct rw_semaphore root_lock; | |
028ae9f7 | 112 | unsigned long flags; |
c6b4fcba JT |
113 | dm_block_t root; |
114 | dm_block_t hint_root; | |
115 | dm_block_t discard_root; | |
116 | ||
117 | sector_t discard_block_size; | |
1bad9bc4 | 118 | dm_dblock_t discard_nr_blocks; |
c6b4fcba JT |
119 | |
120 | sector_t data_block_size; | |
121 | dm_cblock_t cache_blocks; | |
122 | bool changed:1; | |
123 | bool clean_when_opened:1; | |
124 | ||
125 | char policy_name[CACHE_POLICY_NAME_SIZE]; | |
4e7f506f | 126 | unsigned policy_version[CACHE_POLICY_VERSION_SIZE]; |
c6b4fcba JT |
127 | size_t policy_hint_size; |
128 | struct dm_cache_statistics stats; | |
5a32083d JT |
129 | |
130 | /* | |
131 | * Reading the space map root can fail, so we read it into this | |
132 | * buffer before the superblock is locked and updated. | |
133 | */ | |
134 | __u8 metadata_space_map_root[SPACE_MAP_ROOT_SIZE]; | |
028ae9f7 JT |
135 | |
136 | /* | |
137 | * Set if a transaction has to be aborted but the attempt to roll | |
138 | * back to the previous (good) transaction failed. The only | |
139 | * metadata operation permissible in this state is the closing of | |
140 | * the device. | |
141 | */ | |
142 | bool fail_io:1; | |
c6b4fcba JT |
143 | }; |
144 | ||
145 | /*------------------------------------------------------------------- | |
146 | * superblock validator | |
147 | *-----------------------------------------------------------------*/ | |
148 | ||
149 | #define SUPERBLOCK_CSUM_XOR 9031977 | |
150 | ||
151 | static void sb_prepare_for_write(struct dm_block_validator *v, | |
152 | struct dm_block *b, | |
153 | size_t sb_block_size) | |
154 | { | |
155 | struct cache_disk_superblock *disk_super = dm_block_data(b); | |
156 | ||
157 | disk_super->blocknr = cpu_to_le64(dm_block_location(b)); | |
158 | disk_super->csum = cpu_to_le32(dm_bm_checksum(&disk_super->flags, | |
159 | sb_block_size - sizeof(__le32), | |
160 | SUPERBLOCK_CSUM_XOR)); | |
161 | } | |
162 | ||
53d49819 JT |
163 | static int check_metadata_version(struct cache_disk_superblock *disk_super) |
164 | { | |
165 | uint32_t metadata_version = le32_to_cpu(disk_super->version); | |
166 | if (metadata_version < MIN_CACHE_VERSION || metadata_version > MAX_CACHE_VERSION) { | |
167 | DMERR("Cache metadata version %u found, but only versions between %u and %u supported.", | |
168 | metadata_version, MIN_CACHE_VERSION, MAX_CACHE_VERSION); | |
169 | return -EINVAL; | |
170 | } | |
171 | ||
172 | return 0; | |
173 | } | |
174 | ||
c6b4fcba JT |
175 | static int sb_check(struct dm_block_validator *v, |
176 | struct dm_block *b, | |
177 | size_t sb_block_size) | |
178 | { | |
179 | struct cache_disk_superblock *disk_super = dm_block_data(b); | |
180 | __le32 csum_le; | |
181 | ||
182 | if (dm_block_location(b) != le64_to_cpu(disk_super->blocknr)) { | |
183 | DMERR("sb_check failed: blocknr %llu: wanted %llu", | |
184 | le64_to_cpu(disk_super->blocknr), | |
185 | (unsigned long long)dm_block_location(b)); | |
186 | return -ENOTBLK; | |
187 | } | |
188 | ||
189 | if (le64_to_cpu(disk_super->magic) != CACHE_SUPERBLOCK_MAGIC) { | |
190 | DMERR("sb_check failed: magic %llu: wanted %llu", | |
191 | le64_to_cpu(disk_super->magic), | |
192 | (unsigned long long)CACHE_SUPERBLOCK_MAGIC); | |
193 | return -EILSEQ; | |
194 | } | |
195 | ||
196 | csum_le = cpu_to_le32(dm_bm_checksum(&disk_super->flags, | |
197 | sb_block_size - sizeof(__le32), | |
198 | SUPERBLOCK_CSUM_XOR)); | |
199 | if (csum_le != disk_super->csum) { | |
200 | DMERR("sb_check failed: csum %u: wanted %u", | |
201 | le32_to_cpu(csum_le), le32_to_cpu(disk_super->csum)); | |
202 | return -EILSEQ; | |
203 | } | |
204 | ||
53d49819 | 205 | return check_metadata_version(disk_super); |
c6b4fcba JT |
206 | } |
207 | ||
208 | static struct dm_block_validator sb_validator = { | |
209 | .name = "superblock", | |
210 | .prepare_for_write = sb_prepare_for_write, | |
211 | .check = sb_check | |
212 | }; | |
213 | ||
214 | /*----------------------------------------------------------------*/ | |
215 | ||
216 | static int superblock_read_lock(struct dm_cache_metadata *cmd, | |
217 | struct dm_block **sblock) | |
218 | { | |
219 | return dm_bm_read_lock(cmd->bm, CACHE_SUPERBLOCK_LOCATION, | |
220 | &sb_validator, sblock); | |
221 | } | |
222 | ||
223 | static int superblock_lock_zero(struct dm_cache_metadata *cmd, | |
224 | struct dm_block **sblock) | |
225 | { | |
226 | return dm_bm_write_lock_zero(cmd->bm, CACHE_SUPERBLOCK_LOCATION, | |
227 | &sb_validator, sblock); | |
228 | } | |
229 | ||
230 | static int superblock_lock(struct dm_cache_metadata *cmd, | |
231 | struct dm_block **sblock) | |
232 | { | |
233 | return dm_bm_write_lock(cmd->bm, CACHE_SUPERBLOCK_LOCATION, | |
234 | &sb_validator, sblock); | |
235 | } | |
236 | ||
237 | /*----------------------------------------------------------------*/ | |
238 | ||
dd8b0c20 | 239 | static int __superblock_all_zeroes(struct dm_block_manager *bm, bool *result) |
c6b4fcba JT |
240 | { |
241 | int r; | |
242 | unsigned i; | |
243 | struct dm_block *b; | |
244 | __le64 *data_le, zero = cpu_to_le64(0); | |
245 | unsigned sb_block_size = dm_bm_block_size(bm) / sizeof(__le64); | |
246 | ||
247 | /* | |
248 | * We can't use a validator here - it may be all zeroes. | |
249 | */ | |
250 | r = dm_bm_read_lock(bm, CACHE_SUPERBLOCK_LOCATION, NULL, &b); | |
251 | if (r) | |
252 | return r; | |
253 | ||
254 | data_le = dm_block_data(b); | |
dd8b0c20 | 255 | *result = true; |
c6b4fcba JT |
256 | for (i = 0; i < sb_block_size; i++) { |
257 | if (data_le[i] != zero) { | |
dd8b0c20 | 258 | *result = false; |
c6b4fcba JT |
259 | break; |
260 | } | |
261 | } | |
262 | ||
4c7da06f MP |
263 | dm_bm_unlock(b); |
264 | ||
265 | return 0; | |
c6b4fcba JT |
266 | } |
267 | ||
268 | static void __setup_mapping_info(struct dm_cache_metadata *cmd) | |
269 | { | |
270 | struct dm_btree_value_type vt; | |
271 | ||
272 | vt.context = NULL; | |
273 | vt.size = sizeof(__le64); | |
274 | vt.inc = NULL; | |
275 | vt.dec = NULL; | |
276 | vt.equal = NULL; | |
277 | dm_array_info_init(&cmd->info, cmd->tm, &vt); | |
278 | ||
279 | if (cmd->policy_hint_size) { | |
280 | vt.size = sizeof(__le32); | |
281 | dm_array_info_init(&cmd->hint_info, cmd->tm, &vt); | |
282 | } | |
283 | } | |
284 | ||
5a32083d JT |
285 | static int __save_sm_root(struct dm_cache_metadata *cmd) |
286 | { | |
287 | int r; | |
288 | size_t metadata_len; | |
289 | ||
290 | r = dm_sm_root_size(cmd->metadata_sm, &metadata_len); | |
291 | if (r < 0) | |
292 | return r; | |
293 | ||
294 | return dm_sm_copy_root(cmd->metadata_sm, &cmd->metadata_space_map_root, | |
295 | metadata_len); | |
296 | } | |
297 | ||
298 | static void __copy_sm_root(struct dm_cache_metadata *cmd, | |
299 | struct cache_disk_superblock *disk_super) | |
300 | { | |
301 | memcpy(&disk_super->metadata_space_map_root, | |
302 | &cmd->metadata_space_map_root, | |
303 | sizeof(cmd->metadata_space_map_root)); | |
304 | } | |
305 | ||
c6b4fcba JT |
306 | static int __write_initial_superblock(struct dm_cache_metadata *cmd) |
307 | { | |
308 | int r; | |
309 | struct dm_block *sblock; | |
c6b4fcba JT |
310 | struct cache_disk_superblock *disk_super; |
311 | sector_t bdev_size = i_size_read(cmd->bdev->bd_inode) >> SECTOR_SHIFT; | |
312 | ||
313 | /* FIXME: see if we can lose the max sectors limit */ | |
314 | if (bdev_size > DM_CACHE_METADATA_MAX_SECTORS) | |
315 | bdev_size = DM_CACHE_METADATA_MAX_SECTORS; | |
316 | ||
5a32083d | 317 | r = dm_tm_pre_commit(cmd->tm); |
c6b4fcba JT |
318 | if (r < 0) |
319 | return r; | |
320 | ||
5a32083d JT |
321 | /* |
322 | * dm_sm_copy_root() can fail. So we need to do it before we start | |
323 | * updating the superblock. | |
324 | */ | |
325 | r = __save_sm_root(cmd); | |
326 | if (r) | |
c6b4fcba JT |
327 | return r; |
328 | ||
329 | r = superblock_lock_zero(cmd, &sblock); | |
330 | if (r) | |
331 | return r; | |
332 | ||
333 | disk_super = dm_block_data(sblock); | |
334 | disk_super->flags = 0; | |
335 | memset(disk_super->uuid, 0, sizeof(disk_super->uuid)); | |
336 | disk_super->magic = cpu_to_le64(CACHE_SUPERBLOCK_MAGIC); | |
53d49819 | 337 | disk_super->version = cpu_to_le32(MAX_CACHE_VERSION); |
4e7f506f MS |
338 | memset(disk_super->policy_name, 0, sizeof(disk_super->policy_name)); |
339 | memset(disk_super->policy_version, 0, sizeof(disk_super->policy_version)); | |
c6b4fcba JT |
340 | disk_super->policy_hint_size = 0; |
341 | ||
5a32083d | 342 | __copy_sm_root(cmd, disk_super); |
c6b4fcba JT |
343 | |
344 | disk_super->mapping_root = cpu_to_le64(cmd->root); | |
345 | disk_super->hint_root = cpu_to_le64(cmd->hint_root); | |
346 | disk_super->discard_root = cpu_to_le64(cmd->discard_root); | |
347 | disk_super->discard_block_size = cpu_to_le64(cmd->discard_block_size); | |
1bad9bc4 | 348 | disk_super->discard_nr_blocks = cpu_to_le64(from_dblock(cmd->discard_nr_blocks)); |
895b47d7 | 349 | disk_super->metadata_block_size = cpu_to_le32(DM_CACHE_METADATA_BLOCK_SIZE); |
c6b4fcba JT |
350 | disk_super->data_block_size = cpu_to_le32(cmd->data_block_size); |
351 | disk_super->cache_blocks = cpu_to_le32(0); | |
c6b4fcba JT |
352 | |
353 | disk_super->read_hits = cpu_to_le32(0); | |
354 | disk_super->read_misses = cpu_to_le32(0); | |
355 | disk_super->write_hits = cpu_to_le32(0); | |
356 | disk_super->write_misses = cpu_to_le32(0); | |
357 | ||
358 | return dm_tm_commit(cmd->tm, sblock); | |
c6b4fcba JT |
359 | } |
360 | ||
361 | static int __format_metadata(struct dm_cache_metadata *cmd) | |
362 | { | |
363 | int r; | |
364 | ||
365 | r = dm_tm_create_with_sm(cmd->bm, CACHE_SUPERBLOCK_LOCATION, | |
366 | &cmd->tm, &cmd->metadata_sm); | |
367 | if (r < 0) { | |
368 | DMERR("tm_create_with_sm failed"); | |
369 | return r; | |
370 | } | |
371 | ||
372 | __setup_mapping_info(cmd); | |
373 | ||
374 | r = dm_array_empty(&cmd->info, &cmd->root); | |
375 | if (r < 0) | |
376 | goto bad; | |
377 | ||
378 | dm_disk_bitset_init(cmd->tm, &cmd->discard_info); | |
379 | ||
380 | r = dm_bitset_empty(&cmd->discard_info, &cmd->discard_root); | |
381 | if (r < 0) | |
382 | goto bad; | |
383 | ||
384 | cmd->discard_block_size = 0; | |
385 | cmd->discard_nr_blocks = 0; | |
386 | ||
387 | r = __write_initial_superblock(cmd); | |
388 | if (r) | |
389 | goto bad; | |
390 | ||
391 | cmd->clean_when_opened = true; | |
392 | return 0; | |
393 | ||
394 | bad: | |
395 | dm_tm_destroy(cmd->tm); | |
396 | dm_sm_destroy(cmd->metadata_sm); | |
397 | ||
398 | return r; | |
399 | } | |
400 | ||
401 | static int __check_incompat_features(struct cache_disk_superblock *disk_super, | |
402 | struct dm_cache_metadata *cmd) | |
403 | { | |
404 | uint32_t features; | |
405 | ||
406 | features = le32_to_cpu(disk_super->incompat_flags) & ~DM_CACHE_FEATURE_INCOMPAT_SUPP; | |
407 | if (features) { | |
408 | DMERR("could not access metadata due to unsupported optional features (%lx).", | |
409 | (unsigned long)features); | |
410 | return -EINVAL; | |
411 | } | |
412 | ||
413 | /* | |
414 | * Check for read-only metadata to skip the following RDWR checks. | |
415 | */ | |
416 | if (get_disk_ro(cmd->bdev->bd_disk)) | |
417 | return 0; | |
418 | ||
419 | features = le32_to_cpu(disk_super->compat_ro_flags) & ~DM_CACHE_FEATURE_COMPAT_RO_SUPP; | |
420 | if (features) { | |
421 | DMERR("could not access metadata RDWR due to unsupported optional features (%lx).", | |
422 | (unsigned long)features); | |
423 | return -EINVAL; | |
424 | } | |
425 | ||
426 | return 0; | |
427 | } | |
428 | ||
429 | static int __open_metadata(struct dm_cache_metadata *cmd) | |
430 | { | |
431 | int r; | |
432 | struct dm_block *sblock; | |
433 | struct cache_disk_superblock *disk_super; | |
434 | unsigned long sb_flags; | |
435 | ||
436 | r = superblock_read_lock(cmd, &sblock); | |
437 | if (r < 0) { | |
438 | DMERR("couldn't read lock superblock"); | |
439 | return r; | |
440 | } | |
441 | ||
442 | disk_super = dm_block_data(sblock); | |
443 | ||
048e5a07 MS |
444 | /* Verify the data block size hasn't changed */ |
445 | if (le32_to_cpu(disk_super->data_block_size) != cmd->data_block_size) { | |
446 | DMERR("changing the data block size (from %u to %llu) is not supported", | |
447 | le32_to_cpu(disk_super->data_block_size), | |
448 | (unsigned long long)cmd->data_block_size); | |
449 | r = -EINVAL; | |
450 | goto bad; | |
451 | } | |
452 | ||
c6b4fcba JT |
453 | r = __check_incompat_features(disk_super, cmd); |
454 | if (r < 0) | |
455 | goto bad; | |
456 | ||
457 | r = dm_tm_open_with_sm(cmd->bm, CACHE_SUPERBLOCK_LOCATION, | |
458 | disk_super->metadata_space_map_root, | |
459 | sizeof(disk_super->metadata_space_map_root), | |
460 | &cmd->tm, &cmd->metadata_sm); | |
461 | if (r < 0) { | |
462 | DMERR("tm_open_with_sm failed"); | |
463 | goto bad; | |
464 | } | |
465 | ||
466 | __setup_mapping_info(cmd); | |
467 | dm_disk_bitset_init(cmd->tm, &cmd->discard_info); | |
468 | sb_flags = le32_to_cpu(disk_super->flags); | |
469 | cmd->clean_when_opened = test_bit(CLEAN_SHUTDOWN, &sb_flags); | |
4c7da06f MP |
470 | dm_bm_unlock(sblock); |
471 | ||
472 | return 0; | |
c6b4fcba JT |
473 | |
474 | bad: | |
475 | dm_bm_unlock(sblock); | |
476 | return r; | |
477 | } | |
478 | ||
479 | static int __open_or_format_metadata(struct dm_cache_metadata *cmd, | |
480 | bool format_device) | |
481 | { | |
dd8b0c20 JT |
482 | int r; |
483 | bool unformatted = false; | |
c6b4fcba JT |
484 | |
485 | r = __superblock_all_zeroes(cmd->bm, &unformatted); | |
486 | if (r) | |
487 | return r; | |
488 | ||
489 | if (unformatted) | |
490 | return format_device ? __format_metadata(cmd) : -EPERM; | |
491 | ||
492 | return __open_metadata(cmd); | |
493 | } | |
494 | ||
495 | static int __create_persistent_data_objects(struct dm_cache_metadata *cmd, | |
496 | bool may_format_device) | |
497 | { | |
498 | int r; | |
895b47d7 | 499 | cmd->bm = dm_block_manager_create(cmd->bdev, DM_CACHE_METADATA_BLOCK_SIZE << SECTOR_SHIFT, |
c6b4fcba JT |
500 | CACHE_METADATA_CACHE_SIZE, |
501 | CACHE_MAX_CONCURRENT_LOCKS); | |
502 | if (IS_ERR(cmd->bm)) { | |
503 | DMERR("could not create block manager"); | |
504 | return PTR_ERR(cmd->bm); | |
505 | } | |
506 | ||
507 | r = __open_or_format_metadata(cmd, may_format_device); | |
508 | if (r) | |
509 | dm_block_manager_destroy(cmd->bm); | |
510 | ||
511 | return r; | |
512 | } | |
513 | ||
514 | static void __destroy_persistent_data_objects(struct dm_cache_metadata *cmd) | |
515 | { | |
516 | dm_sm_destroy(cmd->metadata_sm); | |
517 | dm_tm_destroy(cmd->tm); | |
518 | dm_block_manager_destroy(cmd->bm); | |
519 | } | |
520 | ||
521 | typedef unsigned long (*flags_mutator)(unsigned long); | |
522 | ||
523 | static void update_flags(struct cache_disk_superblock *disk_super, | |
524 | flags_mutator mutator) | |
525 | { | |
526 | uint32_t sb_flags = mutator(le32_to_cpu(disk_super->flags)); | |
527 | disk_super->flags = cpu_to_le32(sb_flags); | |
528 | } | |
529 | ||
530 | static unsigned long set_clean_shutdown(unsigned long flags) | |
531 | { | |
532 | set_bit(CLEAN_SHUTDOWN, &flags); | |
533 | return flags; | |
534 | } | |
535 | ||
536 | static unsigned long clear_clean_shutdown(unsigned long flags) | |
537 | { | |
538 | clear_bit(CLEAN_SHUTDOWN, &flags); | |
539 | return flags; | |
540 | } | |
541 | ||
542 | static void read_superblock_fields(struct dm_cache_metadata *cmd, | |
543 | struct cache_disk_superblock *disk_super) | |
544 | { | |
028ae9f7 | 545 | cmd->flags = le32_to_cpu(disk_super->flags); |
c6b4fcba JT |
546 | cmd->root = le64_to_cpu(disk_super->mapping_root); |
547 | cmd->hint_root = le64_to_cpu(disk_super->hint_root); | |
548 | cmd->discard_root = le64_to_cpu(disk_super->discard_root); | |
549 | cmd->discard_block_size = le64_to_cpu(disk_super->discard_block_size); | |
1bad9bc4 | 550 | cmd->discard_nr_blocks = to_dblock(le64_to_cpu(disk_super->discard_nr_blocks)); |
c6b4fcba JT |
551 | cmd->data_block_size = le32_to_cpu(disk_super->data_block_size); |
552 | cmd->cache_blocks = to_cblock(le32_to_cpu(disk_super->cache_blocks)); | |
553 | strncpy(cmd->policy_name, disk_super->policy_name, sizeof(cmd->policy_name)); | |
4e7f506f MS |
554 | cmd->policy_version[0] = le32_to_cpu(disk_super->policy_version[0]); |
555 | cmd->policy_version[1] = le32_to_cpu(disk_super->policy_version[1]); | |
556 | cmd->policy_version[2] = le32_to_cpu(disk_super->policy_version[2]); | |
c6b4fcba JT |
557 | cmd->policy_hint_size = le32_to_cpu(disk_super->policy_hint_size); |
558 | ||
559 | cmd->stats.read_hits = le32_to_cpu(disk_super->read_hits); | |
560 | cmd->stats.read_misses = le32_to_cpu(disk_super->read_misses); | |
561 | cmd->stats.write_hits = le32_to_cpu(disk_super->write_hits); | |
562 | cmd->stats.write_misses = le32_to_cpu(disk_super->write_misses); | |
563 | ||
564 | cmd->changed = false; | |
565 | } | |
566 | ||
567 | /* | |
568 | * The mutator updates the superblock flags. | |
569 | */ | |
570 | static int __begin_transaction_flags(struct dm_cache_metadata *cmd, | |
571 | flags_mutator mutator) | |
572 | { | |
573 | int r; | |
574 | struct cache_disk_superblock *disk_super; | |
575 | struct dm_block *sblock; | |
576 | ||
577 | r = superblock_lock(cmd, &sblock); | |
578 | if (r) | |
579 | return r; | |
580 | ||
581 | disk_super = dm_block_data(sblock); | |
582 | update_flags(disk_super, mutator); | |
583 | read_superblock_fields(cmd, disk_super); | |
a9d45396 | 584 | dm_bm_unlock(sblock); |
c6b4fcba | 585 | |
a9d45396 | 586 | return dm_bm_flush(cmd->bm); |
c6b4fcba JT |
587 | } |
588 | ||
589 | static int __begin_transaction(struct dm_cache_metadata *cmd) | |
590 | { | |
591 | int r; | |
592 | struct cache_disk_superblock *disk_super; | |
593 | struct dm_block *sblock; | |
594 | ||
595 | /* | |
596 | * We re-read the superblock every time. Shouldn't need to do this | |
597 | * really. | |
598 | */ | |
599 | r = superblock_read_lock(cmd, &sblock); | |
600 | if (r) | |
601 | return r; | |
602 | ||
603 | disk_super = dm_block_data(sblock); | |
604 | read_superblock_fields(cmd, disk_super); | |
605 | dm_bm_unlock(sblock); | |
606 | ||
607 | return 0; | |
608 | } | |
609 | ||
610 | static int __commit_transaction(struct dm_cache_metadata *cmd, | |
611 | flags_mutator mutator) | |
612 | { | |
613 | int r; | |
c6b4fcba JT |
614 | struct cache_disk_superblock *disk_super; |
615 | struct dm_block *sblock; | |
616 | ||
617 | /* | |
618 | * We need to know if the cache_disk_superblock exceeds a 512-byte sector. | |
619 | */ | |
620 | BUILD_BUG_ON(sizeof(struct cache_disk_superblock) > 512); | |
621 | ||
622 | r = dm_bitset_flush(&cmd->discard_info, cmd->discard_root, | |
623 | &cmd->discard_root); | |
624 | if (r) | |
625 | return r; | |
626 | ||
627 | r = dm_tm_pre_commit(cmd->tm); | |
628 | if (r < 0) | |
629 | return r; | |
630 | ||
5a32083d JT |
631 | r = __save_sm_root(cmd); |
632 | if (r) | |
c6b4fcba JT |
633 | return r; |
634 | ||
635 | r = superblock_lock(cmd, &sblock); | |
636 | if (r) | |
637 | return r; | |
638 | ||
639 | disk_super = dm_block_data(sblock); | |
640 | ||
3201ac45 | 641 | disk_super->flags = cpu_to_le32(cmd->flags); |
c6b4fcba JT |
642 | if (mutator) |
643 | update_flags(disk_super, mutator); | |
644 | ||
645 | disk_super->mapping_root = cpu_to_le64(cmd->root); | |
646 | disk_super->hint_root = cpu_to_le64(cmd->hint_root); | |
647 | disk_super->discard_root = cpu_to_le64(cmd->discard_root); | |
648 | disk_super->discard_block_size = cpu_to_le64(cmd->discard_block_size); | |
1bad9bc4 | 649 | disk_super->discard_nr_blocks = cpu_to_le64(from_dblock(cmd->discard_nr_blocks)); |
c6b4fcba JT |
650 | disk_super->cache_blocks = cpu_to_le32(from_cblock(cmd->cache_blocks)); |
651 | strncpy(disk_super->policy_name, cmd->policy_name, sizeof(disk_super->policy_name)); | |
4e7f506f MS |
652 | disk_super->policy_version[0] = cpu_to_le32(cmd->policy_version[0]); |
653 | disk_super->policy_version[1] = cpu_to_le32(cmd->policy_version[1]); | |
654 | disk_super->policy_version[2] = cpu_to_le32(cmd->policy_version[2]); | |
c6b4fcba JT |
655 | |
656 | disk_super->read_hits = cpu_to_le32(cmd->stats.read_hits); | |
657 | disk_super->read_misses = cpu_to_le32(cmd->stats.read_misses); | |
658 | disk_super->write_hits = cpu_to_le32(cmd->stats.write_hits); | |
659 | disk_super->write_misses = cpu_to_le32(cmd->stats.write_misses); | |
5a32083d | 660 | __copy_sm_root(cmd, disk_super); |
c6b4fcba JT |
661 | |
662 | return dm_tm_commit(cmd->tm, sblock); | |
663 | } | |
664 | ||
665 | /*----------------------------------------------------------------*/ | |
666 | ||
667 | /* | |
668 | * The mappings are held in a dm-array that has 64-bit values stored in | |
669 | * little-endian format. The index is the cblock, the high 48bits of the | |
670 | * value are the oblock and the low 16 bit the flags. | |
671 | */ | |
672 | #define FLAGS_MASK ((1 << 16) - 1) | |
673 | ||
674 | static __le64 pack_value(dm_oblock_t block, unsigned flags) | |
675 | { | |
676 | uint64_t value = from_oblock(block); | |
677 | value <<= 16; | |
678 | value = value | (flags & FLAGS_MASK); | |
679 | return cpu_to_le64(value); | |
680 | } | |
681 | ||
682 | static void unpack_value(__le64 value_le, dm_oblock_t *block, unsigned *flags) | |
683 | { | |
684 | uint64_t value = le64_to_cpu(value_le); | |
685 | uint64_t b = value >> 16; | |
686 | *block = to_oblock(b); | |
687 | *flags = value & FLAGS_MASK; | |
688 | } | |
689 | ||
690 | /*----------------------------------------------------------------*/ | |
691 | ||
9b1cc9f2 JT |
692 | static struct dm_cache_metadata *metadata_open(struct block_device *bdev, |
693 | sector_t data_block_size, | |
694 | bool may_format_device, | |
695 | size_t policy_hint_size) | |
c6b4fcba JT |
696 | { |
697 | int r; | |
698 | struct dm_cache_metadata *cmd; | |
699 | ||
700 | cmd = kzalloc(sizeof(*cmd), GFP_KERNEL); | |
701 | if (!cmd) { | |
702 | DMERR("could not allocate metadata struct"); | |
766a7888 | 703 | return ERR_PTR(-ENOMEM); |
c6b4fcba JT |
704 | } |
705 | ||
9b1cc9f2 | 706 | atomic_set(&cmd->ref_count, 1); |
c6b4fcba JT |
707 | init_rwsem(&cmd->root_lock); |
708 | cmd->bdev = bdev; | |
709 | cmd->data_block_size = data_block_size; | |
710 | cmd->cache_blocks = 0; | |
711 | cmd->policy_hint_size = policy_hint_size; | |
712 | cmd->changed = true; | |
028ae9f7 | 713 | cmd->fail_io = false; |
c6b4fcba JT |
714 | |
715 | r = __create_persistent_data_objects(cmd, may_format_device); | |
716 | if (r) { | |
717 | kfree(cmd); | |
718 | return ERR_PTR(r); | |
719 | } | |
720 | ||
721 | r = __begin_transaction_flags(cmd, clear_clean_shutdown); | |
722 | if (r < 0) { | |
723 | dm_cache_metadata_close(cmd); | |
724 | return ERR_PTR(r); | |
725 | } | |
726 | ||
727 | return cmd; | |
728 | } | |
729 | ||
9b1cc9f2 JT |
730 | /* |
731 | * We keep a little list of ref counted metadata objects to prevent two | |
732 | * different target instances creating separate bufio instances. This is | |
733 | * an issue if a table is reloaded before the suspend. | |
734 | */ | |
735 | static DEFINE_MUTEX(table_lock); | |
736 | static LIST_HEAD(table); | |
737 | ||
738 | static struct dm_cache_metadata *lookup(struct block_device *bdev) | |
739 | { | |
740 | struct dm_cache_metadata *cmd; | |
741 | ||
742 | list_for_each_entry(cmd, &table, list) | |
743 | if (cmd->bdev == bdev) { | |
744 | atomic_inc(&cmd->ref_count); | |
745 | return cmd; | |
746 | } | |
747 | ||
748 | return NULL; | |
749 | } | |
750 | ||
751 | static struct dm_cache_metadata *lookup_or_open(struct block_device *bdev, | |
752 | sector_t data_block_size, | |
753 | bool may_format_device, | |
754 | size_t policy_hint_size) | |
755 | { | |
756 | struct dm_cache_metadata *cmd, *cmd2; | |
757 | ||
758 | mutex_lock(&table_lock); | |
759 | cmd = lookup(bdev); | |
760 | mutex_unlock(&table_lock); | |
761 | ||
762 | if (cmd) | |
763 | return cmd; | |
764 | ||
765 | cmd = metadata_open(bdev, data_block_size, may_format_device, policy_hint_size); | |
766a7888 | 766 | if (!IS_ERR(cmd)) { |
9b1cc9f2 JT |
767 | mutex_lock(&table_lock); |
768 | cmd2 = lookup(bdev); | |
769 | if (cmd2) { | |
770 | mutex_unlock(&table_lock); | |
771 | __destroy_persistent_data_objects(cmd); | |
772 | kfree(cmd); | |
773 | return cmd2; | |
774 | } | |
775 | list_add(&cmd->list, &table); | |
776 | mutex_unlock(&table_lock); | |
777 | } | |
778 | ||
779 | return cmd; | |
780 | } | |
781 | ||
782 | static bool same_params(struct dm_cache_metadata *cmd, sector_t data_block_size) | |
783 | { | |
784 | if (cmd->data_block_size != data_block_size) { | |
785 | DMERR("data_block_size (%llu) different from that in metadata (%llu)\n", | |
786 | (unsigned long long) data_block_size, | |
787 | (unsigned long long) cmd->data_block_size); | |
788 | return false; | |
789 | } | |
790 | ||
791 | return true; | |
792 | } | |
793 | ||
794 | struct dm_cache_metadata *dm_cache_metadata_open(struct block_device *bdev, | |
795 | sector_t data_block_size, | |
796 | bool may_format_device, | |
797 | size_t policy_hint_size) | |
798 | { | |
799 | struct dm_cache_metadata *cmd = lookup_or_open(bdev, data_block_size, | |
800 | may_format_device, policy_hint_size); | |
766a7888 JT |
801 | |
802 | if (!IS_ERR(cmd) && !same_params(cmd, data_block_size)) { | |
9b1cc9f2 | 803 | dm_cache_metadata_close(cmd); |
766a7888 | 804 | return ERR_PTR(-EINVAL); |
9b1cc9f2 JT |
805 | } |
806 | ||
807 | return cmd; | |
808 | } | |
809 | ||
c6b4fcba JT |
810 | void dm_cache_metadata_close(struct dm_cache_metadata *cmd) |
811 | { | |
9b1cc9f2 JT |
812 | if (atomic_dec_and_test(&cmd->ref_count)) { |
813 | mutex_lock(&table_lock); | |
814 | list_del(&cmd->list); | |
815 | mutex_unlock(&table_lock); | |
816 | ||
028ae9f7 JT |
817 | if (!cmd->fail_io) |
818 | __destroy_persistent_data_objects(cmd); | |
9b1cc9f2 JT |
819 | kfree(cmd); |
820 | } | |
c6b4fcba JT |
821 | } |
822 | ||
f494a9c6 JT |
823 | /* |
824 | * Checks that the given cache block is either unmapped or clean. | |
825 | */ | |
826 | static int block_unmapped_or_clean(struct dm_cache_metadata *cmd, dm_cblock_t b, | |
827 | bool *result) | |
828 | { | |
829 | int r; | |
830 | __le64 value; | |
831 | dm_oblock_t ob; | |
832 | unsigned flags; | |
833 | ||
834 | r = dm_array_get_value(&cmd->info, cmd->root, from_cblock(b), &value); | |
835 | if (r) { | |
836 | DMERR("block_unmapped_or_clean failed"); | |
837 | return r; | |
838 | } | |
839 | ||
840 | unpack_value(value, &ob, &flags); | |
841 | *result = !((flags & M_VALID) && (flags & M_DIRTY)); | |
842 | ||
843 | return 0; | |
844 | } | |
845 | ||
846 | static int blocks_are_unmapped_or_clean(struct dm_cache_metadata *cmd, | |
847 | dm_cblock_t begin, dm_cblock_t end, | |
848 | bool *result) | |
849 | { | |
850 | int r; | |
851 | *result = true; | |
852 | ||
853 | while (begin != end) { | |
854 | r = block_unmapped_or_clean(cmd, begin, result); | |
855 | if (r) | |
856 | return r; | |
857 | ||
858 | if (!*result) { | |
859 | DMERR("cache block %llu is dirty", | |
860 | (unsigned long long) from_cblock(begin)); | |
861 | return 0; | |
862 | } | |
863 | ||
864 | begin = to_cblock(from_cblock(begin) + 1); | |
865 | } | |
866 | ||
867 | return 0; | |
868 | } | |
869 | ||
9567366f MS |
870 | static bool cmd_write_lock(struct dm_cache_metadata *cmd) |
871 | { | |
872 | down_write(&cmd->root_lock); | |
873 | if (cmd->fail_io || dm_bm_is_read_only(cmd->bm)) { | |
874 | up_write(&cmd->root_lock); | |
875 | return false; | |
d14fcf3d | 876 | } |
9567366f MS |
877 | return true; |
878 | } | |
028ae9f7 | 879 | |
9567366f MS |
880 | #define WRITE_LOCK(cmd) \ |
881 | do { \ | |
882 | if (!cmd_write_lock((cmd))) \ | |
883 | return -EINVAL; \ | |
884 | } while(0) | |
885 | ||
886 | #define WRITE_LOCK_VOID(cmd) \ | |
887 | do { \ | |
888 | if (!cmd_write_lock((cmd))) \ | |
889 | return; \ | |
890 | } while(0) | |
028ae9f7 JT |
891 | |
892 | #define WRITE_UNLOCK(cmd) \ | |
9567366f | 893 | up_write(&(cmd)->root_lock) |
028ae9f7 | 894 | |
9567366f MS |
895 | static bool cmd_read_lock(struct dm_cache_metadata *cmd) |
896 | { | |
6545b60b | 897 | down_read(&cmd->root_lock); |
9567366f | 898 | if (cmd->fail_io) { |
6545b60b | 899 | up_read(&cmd->root_lock); |
9567366f | 900 | return false; |
d14fcf3d | 901 | } |
9567366f MS |
902 | return true; |
903 | } | |
d14fcf3d | 904 | |
9567366f MS |
905 | #define READ_LOCK(cmd) \ |
906 | do { \ | |
907 | if (!cmd_read_lock((cmd))) \ | |
908 | return -EINVAL; \ | |
909 | } while(0) | |
910 | ||
911 | #define READ_LOCK_VOID(cmd) \ | |
912 | do { \ | |
913 | if (!cmd_read_lock((cmd))) \ | |
914 | return; \ | |
915 | } while(0) | |
d14fcf3d JT |
916 | |
917 | #define READ_UNLOCK(cmd) \ | |
9567366f | 918 | up_read(&(cmd)->root_lock) |
d14fcf3d | 919 | |
c6b4fcba JT |
920 | int dm_cache_resize(struct dm_cache_metadata *cmd, dm_cblock_t new_cache_size) |
921 | { | |
922 | int r; | |
f494a9c6 | 923 | bool clean; |
c6b4fcba JT |
924 | __le64 null_mapping = pack_value(0, 0); |
925 | ||
028ae9f7 | 926 | WRITE_LOCK(cmd); |
c6b4fcba | 927 | __dm_bless_for_disk(&null_mapping); |
f494a9c6 JT |
928 | |
929 | if (from_cblock(new_cache_size) < from_cblock(cmd->cache_blocks)) { | |
930 | r = blocks_are_unmapped_or_clean(cmd, new_cache_size, cmd->cache_blocks, &clean); | |
931 | if (r) { | |
932 | __dm_unbless_for_disk(&null_mapping); | |
933 | goto out; | |
934 | } | |
935 | ||
936 | if (!clean) { | |
937 | DMERR("unable to shrink cache due to dirty blocks"); | |
938 | r = -EINVAL; | |
939 | __dm_unbless_for_disk(&null_mapping); | |
940 | goto out; | |
941 | } | |
942 | } | |
943 | ||
c6b4fcba JT |
944 | r = dm_array_resize(&cmd->info, cmd->root, from_cblock(cmd->cache_blocks), |
945 | from_cblock(new_cache_size), | |
946 | &null_mapping, &cmd->root); | |
947 | if (!r) | |
948 | cmd->cache_blocks = new_cache_size; | |
949 | cmd->changed = true; | |
f494a9c6 JT |
950 | |
951 | out: | |
028ae9f7 | 952 | WRITE_UNLOCK(cmd); |
c6b4fcba JT |
953 | |
954 | return r; | |
955 | } | |
956 | ||
957 | int dm_cache_discard_bitset_resize(struct dm_cache_metadata *cmd, | |
958 | sector_t discard_block_size, | |
1bad9bc4 | 959 | dm_dblock_t new_nr_entries) |
c6b4fcba JT |
960 | { |
961 | int r; | |
962 | ||
028ae9f7 | 963 | WRITE_LOCK(cmd); |
c6b4fcba JT |
964 | r = dm_bitset_resize(&cmd->discard_info, |
965 | cmd->discard_root, | |
1bad9bc4 JT |
966 | from_dblock(cmd->discard_nr_blocks), |
967 | from_dblock(new_nr_entries), | |
c6b4fcba JT |
968 | false, &cmd->discard_root); |
969 | if (!r) { | |
970 | cmd->discard_block_size = discard_block_size; | |
971 | cmd->discard_nr_blocks = new_nr_entries; | |
972 | } | |
973 | ||
974 | cmd->changed = true; | |
028ae9f7 | 975 | WRITE_UNLOCK(cmd); |
c6b4fcba JT |
976 | |
977 | return r; | |
978 | } | |
979 | ||
1bad9bc4 | 980 | static int __set_discard(struct dm_cache_metadata *cmd, dm_dblock_t b) |
c6b4fcba JT |
981 | { |
982 | return dm_bitset_set_bit(&cmd->discard_info, cmd->discard_root, | |
1bad9bc4 | 983 | from_dblock(b), &cmd->discard_root); |
c6b4fcba JT |
984 | } |
985 | ||
1bad9bc4 | 986 | static int __clear_discard(struct dm_cache_metadata *cmd, dm_dblock_t b) |
c6b4fcba JT |
987 | { |
988 | return dm_bitset_clear_bit(&cmd->discard_info, cmd->discard_root, | |
1bad9bc4 | 989 | from_dblock(b), &cmd->discard_root); |
c6b4fcba JT |
990 | } |
991 | ||
1bad9bc4 | 992 | static int __is_discarded(struct dm_cache_metadata *cmd, dm_dblock_t b, |
c6b4fcba JT |
993 | bool *is_discarded) |
994 | { | |
995 | return dm_bitset_test_bit(&cmd->discard_info, cmd->discard_root, | |
1bad9bc4 | 996 | from_dblock(b), &cmd->discard_root, |
c6b4fcba JT |
997 | is_discarded); |
998 | } | |
999 | ||
1000 | static int __discard(struct dm_cache_metadata *cmd, | |
1bad9bc4 | 1001 | dm_dblock_t dblock, bool discard) |
c6b4fcba JT |
1002 | { |
1003 | int r; | |
1004 | ||
1005 | r = (discard ? __set_discard : __clear_discard)(cmd, dblock); | |
1006 | if (r) | |
1007 | return r; | |
1008 | ||
1009 | cmd->changed = true; | |
1010 | return 0; | |
1011 | } | |
1012 | ||
1013 | int dm_cache_set_discard(struct dm_cache_metadata *cmd, | |
1bad9bc4 | 1014 | dm_dblock_t dblock, bool discard) |
c6b4fcba JT |
1015 | { |
1016 | int r; | |
1017 | ||
028ae9f7 | 1018 | WRITE_LOCK(cmd); |
c6b4fcba | 1019 | r = __discard(cmd, dblock, discard); |
028ae9f7 | 1020 | WRITE_UNLOCK(cmd); |
c6b4fcba JT |
1021 | |
1022 | return r; | |
1023 | } | |
1024 | ||
1025 | static int __load_discards(struct dm_cache_metadata *cmd, | |
1026 | load_discard_fn fn, void *context) | |
1027 | { | |
1028 | int r = 0; | |
1029 | dm_block_t b; | |
1030 | bool discard; | |
1031 | ||
1bad9bc4 JT |
1032 | for (b = 0; b < from_dblock(cmd->discard_nr_blocks); b++) { |
1033 | dm_dblock_t dblock = to_dblock(b); | |
c6b4fcba JT |
1034 | |
1035 | if (cmd->clean_when_opened) { | |
1036 | r = __is_discarded(cmd, dblock, &discard); | |
1037 | if (r) | |
1038 | return r; | |
1039 | } else | |
1040 | discard = false; | |
1041 | ||
1042 | r = fn(context, cmd->discard_block_size, dblock, discard); | |
1043 | if (r) | |
1044 | break; | |
1045 | } | |
1046 | ||
1047 | return r; | |
1048 | } | |
1049 | ||
1050 | int dm_cache_load_discards(struct dm_cache_metadata *cmd, | |
1051 | load_discard_fn fn, void *context) | |
1052 | { | |
1053 | int r; | |
1054 | ||
d14fcf3d | 1055 | READ_LOCK(cmd); |
c6b4fcba | 1056 | r = __load_discards(cmd, fn, context); |
d14fcf3d | 1057 | READ_UNLOCK(cmd); |
c6b4fcba JT |
1058 | |
1059 | return r; | |
1060 | } | |
1061 | ||
d14fcf3d | 1062 | int dm_cache_size(struct dm_cache_metadata *cmd, dm_cblock_t *result) |
c6b4fcba | 1063 | { |
d14fcf3d JT |
1064 | READ_LOCK(cmd); |
1065 | *result = cmd->cache_blocks; | |
1066 | READ_UNLOCK(cmd); | |
c6b4fcba | 1067 | |
d14fcf3d | 1068 | return 0; |
c6b4fcba JT |
1069 | } |
1070 | ||
1071 | static int __remove(struct dm_cache_metadata *cmd, dm_cblock_t cblock) | |
1072 | { | |
1073 | int r; | |
1074 | __le64 value = pack_value(0, 0); | |
1075 | ||
1076 | __dm_bless_for_disk(&value); | |
1077 | r = dm_array_set_value(&cmd->info, cmd->root, from_cblock(cblock), | |
1078 | &value, &cmd->root); | |
1079 | if (r) | |
1080 | return r; | |
1081 | ||
1082 | cmd->changed = true; | |
1083 | return 0; | |
1084 | } | |
1085 | ||
1086 | int dm_cache_remove_mapping(struct dm_cache_metadata *cmd, dm_cblock_t cblock) | |
1087 | { | |
1088 | int r; | |
1089 | ||
028ae9f7 | 1090 | WRITE_LOCK(cmd); |
c6b4fcba | 1091 | r = __remove(cmd, cblock); |
028ae9f7 | 1092 | WRITE_UNLOCK(cmd); |
c6b4fcba JT |
1093 | |
1094 | return r; | |
1095 | } | |
1096 | ||
1097 | static int __insert(struct dm_cache_metadata *cmd, | |
1098 | dm_cblock_t cblock, dm_oblock_t oblock) | |
1099 | { | |
1100 | int r; | |
1101 | __le64 value = pack_value(oblock, M_VALID); | |
1102 | __dm_bless_for_disk(&value); | |
1103 | ||
1104 | r = dm_array_set_value(&cmd->info, cmd->root, from_cblock(cblock), | |
1105 | &value, &cmd->root); | |
1106 | if (r) | |
1107 | return r; | |
1108 | ||
1109 | cmd->changed = true; | |
1110 | return 0; | |
1111 | } | |
1112 | ||
1113 | int dm_cache_insert_mapping(struct dm_cache_metadata *cmd, | |
1114 | dm_cblock_t cblock, dm_oblock_t oblock) | |
1115 | { | |
1116 | int r; | |
1117 | ||
028ae9f7 | 1118 | WRITE_LOCK(cmd); |
c6b4fcba | 1119 | r = __insert(cmd, cblock, oblock); |
028ae9f7 | 1120 | WRITE_UNLOCK(cmd); |
c6b4fcba JT |
1121 | |
1122 | return r; | |
1123 | } | |
1124 | ||
1125 | struct thunk { | |
1126 | load_mapping_fn fn; | |
1127 | void *context; | |
1128 | ||
1129 | struct dm_cache_metadata *cmd; | |
1130 | bool respect_dirty_flags; | |
1131 | bool hints_valid; | |
1132 | }; | |
1133 | ||
ea2dd8c1 MS |
1134 | static bool policy_unchanged(struct dm_cache_metadata *cmd, |
1135 | struct dm_cache_policy *policy) | |
1136 | { | |
1137 | const char *policy_name = dm_cache_policy_get_name(policy); | |
1138 | const unsigned *policy_version = dm_cache_policy_get_version(policy); | |
1139 | size_t policy_hint_size = dm_cache_policy_get_hint_size(policy); | |
1140 | ||
1141 | /* | |
1142 | * Ensure policy names match. | |
1143 | */ | |
1144 | if (strncmp(cmd->policy_name, policy_name, sizeof(cmd->policy_name))) | |
1145 | return false; | |
1146 | ||
1147 | /* | |
1148 | * Ensure policy major versions match. | |
1149 | */ | |
1150 | if (cmd->policy_version[0] != policy_version[0]) | |
1151 | return false; | |
1152 | ||
1153 | /* | |
1154 | * Ensure policy hint sizes match. | |
1155 | */ | |
1156 | if (cmd->policy_hint_size != policy_hint_size) | |
1157 | return false; | |
1158 | ||
1159 | return true; | |
1160 | } | |
1161 | ||
c6b4fcba JT |
1162 | static bool hints_array_initialized(struct dm_cache_metadata *cmd) |
1163 | { | |
1164 | return cmd->hint_root && cmd->policy_hint_size; | |
1165 | } | |
1166 | ||
1167 | static bool hints_array_available(struct dm_cache_metadata *cmd, | |
ea2dd8c1 | 1168 | struct dm_cache_policy *policy) |
c6b4fcba | 1169 | { |
ea2dd8c1 | 1170 | return cmd->clean_when_opened && policy_unchanged(cmd, policy) && |
c6b4fcba JT |
1171 | hints_array_initialized(cmd); |
1172 | } | |
1173 | ||
1174 | static int __load_mapping(void *context, uint64_t cblock, void *leaf) | |
1175 | { | |
1176 | int r = 0; | |
1177 | bool dirty; | |
1178 | __le64 value; | |
1179 | __le32 hint_value = 0; | |
1180 | dm_oblock_t oblock; | |
1181 | unsigned flags; | |
1182 | struct thunk *thunk = context; | |
1183 | struct dm_cache_metadata *cmd = thunk->cmd; | |
1184 | ||
1185 | memcpy(&value, leaf, sizeof(value)); | |
1186 | unpack_value(value, &oblock, &flags); | |
1187 | ||
1188 | if (flags & M_VALID) { | |
1189 | if (thunk->hints_valid) { | |
1190 | r = dm_array_get_value(&cmd->hint_info, cmd->hint_root, | |
1191 | cblock, &hint_value); | |
1192 | if (r && r != -ENODATA) | |
1193 | return r; | |
1194 | } | |
1195 | ||
1196 | dirty = thunk->respect_dirty_flags ? (flags & M_DIRTY) : true; | |
1197 | r = thunk->fn(thunk->context, oblock, to_cblock(cblock), | |
1198 | dirty, le32_to_cpu(hint_value), thunk->hints_valid); | |
1199 | } | |
1200 | ||
1201 | return r; | |
1202 | } | |
1203 | ||
ea2dd8c1 MS |
1204 | static int __load_mappings(struct dm_cache_metadata *cmd, |
1205 | struct dm_cache_policy *policy, | |
c6b4fcba JT |
1206 | load_mapping_fn fn, void *context) |
1207 | { | |
1208 | struct thunk thunk; | |
1209 | ||
1210 | thunk.fn = fn; | |
1211 | thunk.context = context; | |
1212 | ||
1213 | thunk.cmd = cmd; | |
1214 | thunk.respect_dirty_flags = cmd->clean_when_opened; | |
ea2dd8c1 | 1215 | thunk.hints_valid = hints_array_available(cmd, policy); |
c6b4fcba JT |
1216 | |
1217 | return dm_array_walk(&cmd->info, cmd->root, __load_mapping, &thunk); | |
1218 | } | |
1219 | ||
ea2dd8c1 MS |
1220 | int dm_cache_load_mappings(struct dm_cache_metadata *cmd, |
1221 | struct dm_cache_policy *policy, | |
c6b4fcba JT |
1222 | load_mapping_fn fn, void *context) |
1223 | { | |
1224 | int r; | |
1225 | ||
d14fcf3d | 1226 | READ_LOCK(cmd); |
ea2dd8c1 | 1227 | r = __load_mappings(cmd, policy, fn, context); |
d14fcf3d | 1228 | READ_UNLOCK(cmd); |
c6b4fcba JT |
1229 | |
1230 | return r; | |
1231 | } | |
1232 | ||
1233 | static int __dump_mapping(void *context, uint64_t cblock, void *leaf) | |
1234 | { | |
1235 | int r = 0; | |
1236 | __le64 value; | |
1237 | dm_oblock_t oblock; | |
1238 | unsigned flags; | |
1239 | ||
1240 | memcpy(&value, leaf, sizeof(value)); | |
1241 | unpack_value(value, &oblock, &flags); | |
1242 | ||
1243 | return r; | |
1244 | } | |
1245 | ||
1246 | static int __dump_mappings(struct dm_cache_metadata *cmd) | |
1247 | { | |
1248 | return dm_array_walk(&cmd->info, cmd->root, __dump_mapping, NULL); | |
1249 | } | |
1250 | ||
1251 | void dm_cache_dump(struct dm_cache_metadata *cmd) | |
1252 | { | |
d14fcf3d | 1253 | READ_LOCK_VOID(cmd); |
c6b4fcba | 1254 | __dump_mappings(cmd); |
d14fcf3d | 1255 | READ_UNLOCK(cmd); |
c6b4fcba JT |
1256 | } |
1257 | ||
1258 | int dm_cache_changed_this_transaction(struct dm_cache_metadata *cmd) | |
1259 | { | |
1260 | int r; | |
1261 | ||
d14fcf3d | 1262 | READ_LOCK(cmd); |
c6b4fcba | 1263 | r = cmd->changed; |
d14fcf3d | 1264 | READ_UNLOCK(cmd); |
c6b4fcba JT |
1265 | |
1266 | return r; | |
1267 | } | |
1268 | ||
1269 | static int __dirty(struct dm_cache_metadata *cmd, dm_cblock_t cblock, bool dirty) | |
1270 | { | |
1271 | int r; | |
1272 | unsigned flags; | |
1273 | dm_oblock_t oblock; | |
1274 | __le64 value; | |
1275 | ||
1276 | r = dm_array_get_value(&cmd->info, cmd->root, from_cblock(cblock), &value); | |
1277 | if (r) | |
1278 | return r; | |
1279 | ||
1280 | unpack_value(value, &oblock, &flags); | |
1281 | ||
1282 | if (((flags & M_DIRTY) && dirty) || (!(flags & M_DIRTY) && !dirty)) | |
1283 | /* nothing to be done */ | |
1284 | return 0; | |
1285 | ||
79ed9caf | 1286 | value = pack_value(oblock, (flags & ~M_DIRTY) | (dirty ? M_DIRTY : 0)); |
c6b4fcba JT |
1287 | __dm_bless_for_disk(&value); |
1288 | ||
1289 | r = dm_array_set_value(&cmd->info, cmd->root, from_cblock(cblock), | |
1290 | &value, &cmd->root); | |
1291 | if (r) | |
1292 | return r; | |
1293 | ||
1294 | cmd->changed = true; | |
1295 | return 0; | |
1296 | ||
1297 | } | |
1298 | ||
1299 | int dm_cache_set_dirty(struct dm_cache_metadata *cmd, | |
1300 | dm_cblock_t cblock, bool dirty) | |
1301 | { | |
1302 | int r; | |
1303 | ||
028ae9f7 | 1304 | WRITE_LOCK(cmd); |
c6b4fcba | 1305 | r = __dirty(cmd, cblock, dirty); |
028ae9f7 | 1306 | WRITE_UNLOCK(cmd); |
c6b4fcba JT |
1307 | |
1308 | return r; | |
1309 | } | |
1310 | ||
1311 | void dm_cache_metadata_get_stats(struct dm_cache_metadata *cmd, | |
1312 | struct dm_cache_statistics *stats) | |
1313 | { | |
d14fcf3d | 1314 | READ_LOCK_VOID(cmd); |
8c5008fa | 1315 | *stats = cmd->stats; |
d14fcf3d | 1316 | READ_UNLOCK(cmd); |
c6b4fcba JT |
1317 | } |
1318 | ||
1319 | void dm_cache_metadata_set_stats(struct dm_cache_metadata *cmd, | |
1320 | struct dm_cache_statistics *stats) | |
1321 | { | |
028ae9f7 | 1322 | WRITE_LOCK_VOID(cmd); |
8c5008fa | 1323 | cmd->stats = *stats; |
028ae9f7 | 1324 | WRITE_UNLOCK(cmd); |
c6b4fcba JT |
1325 | } |
1326 | ||
1327 | int dm_cache_commit(struct dm_cache_metadata *cmd, bool clean_shutdown) | |
1328 | { | |
1329 | int r; | |
1330 | flags_mutator mutator = (clean_shutdown ? set_clean_shutdown : | |
1331 | clear_clean_shutdown); | |
1332 | ||
028ae9f7 | 1333 | WRITE_LOCK(cmd); |
c6b4fcba JT |
1334 | r = __commit_transaction(cmd, mutator); |
1335 | if (r) | |
1336 | goto out; | |
1337 | ||
1338 | r = __begin_transaction(cmd); | |
1339 | ||
1340 | out: | |
028ae9f7 | 1341 | WRITE_UNLOCK(cmd); |
c6b4fcba JT |
1342 | return r; |
1343 | } | |
1344 | ||
1345 | int dm_cache_get_free_metadata_block_count(struct dm_cache_metadata *cmd, | |
1346 | dm_block_t *result) | |
1347 | { | |
1348 | int r = -EINVAL; | |
1349 | ||
d14fcf3d | 1350 | READ_LOCK(cmd); |
c6b4fcba | 1351 | r = dm_sm_get_nr_free(cmd->metadata_sm, result); |
d14fcf3d | 1352 | READ_UNLOCK(cmd); |
c6b4fcba JT |
1353 | |
1354 | return r; | |
1355 | } | |
1356 | ||
1357 | int dm_cache_get_metadata_dev_size(struct dm_cache_metadata *cmd, | |
1358 | dm_block_t *result) | |
1359 | { | |
1360 | int r = -EINVAL; | |
1361 | ||
d14fcf3d | 1362 | READ_LOCK(cmd); |
c6b4fcba | 1363 | r = dm_sm_get_nr_blocks(cmd->metadata_sm, result); |
d14fcf3d | 1364 | READ_UNLOCK(cmd); |
c6b4fcba JT |
1365 | |
1366 | return r; | |
1367 | } | |
1368 | ||
1369 | /*----------------------------------------------------------------*/ | |
1370 | ||
1371 | static int begin_hints(struct dm_cache_metadata *cmd, struct dm_cache_policy *policy) | |
1372 | { | |
1373 | int r; | |
1374 | __le32 value; | |
1375 | size_t hint_size; | |
1376 | const char *policy_name = dm_cache_policy_get_name(policy); | |
4e7f506f | 1377 | const unsigned *policy_version = dm_cache_policy_get_version(policy); |
c6b4fcba JT |
1378 | |
1379 | if (!policy_name[0] || | |
1380 | (strlen(policy_name) > sizeof(cmd->policy_name) - 1)) | |
1381 | return -EINVAL; | |
1382 | ||
ea2dd8c1 | 1383 | if (!policy_unchanged(cmd, policy)) { |
c6b4fcba | 1384 | strncpy(cmd->policy_name, policy_name, sizeof(cmd->policy_name)); |
4e7f506f | 1385 | memcpy(cmd->policy_version, policy_version, sizeof(cmd->policy_version)); |
c6b4fcba JT |
1386 | |
1387 | hint_size = dm_cache_policy_get_hint_size(policy); | |
1388 | if (!hint_size) | |
1389 | return 0; /* short-circuit hints initialization */ | |
1390 | cmd->policy_hint_size = hint_size; | |
1391 | ||
1392 | if (cmd->hint_root) { | |
1393 | r = dm_array_del(&cmd->hint_info, cmd->hint_root); | |
1394 | if (r) | |
1395 | return r; | |
1396 | } | |
1397 | ||
1398 | r = dm_array_empty(&cmd->hint_info, &cmd->hint_root); | |
1399 | if (r) | |
1400 | return r; | |
1401 | ||
1402 | value = cpu_to_le32(0); | |
1403 | __dm_bless_for_disk(&value); | |
1404 | r = dm_array_resize(&cmd->hint_info, cmd->hint_root, 0, | |
1405 | from_cblock(cmd->cache_blocks), | |
1406 | &value, &cmd->hint_root); | |
1407 | if (r) | |
1408 | return r; | |
1409 | } | |
1410 | ||
1411 | return 0; | |
1412 | } | |
1413 | ||
0596661f | 1414 | static int save_hint(void *context, dm_cblock_t cblock, dm_oblock_t oblock, uint32_t hint) |
c6b4fcba | 1415 | { |
0596661f JT |
1416 | struct dm_cache_metadata *cmd = context; |
1417 | __le32 value = cpu_to_le32(hint); | |
c6b4fcba JT |
1418 | int r; |
1419 | ||
c6b4fcba JT |
1420 | __dm_bless_for_disk(&value); |
1421 | ||
1422 | r = dm_array_set_value(&cmd->hint_info, cmd->hint_root, | |
1423 | from_cblock(cblock), &value, &cmd->hint_root); | |
1424 | cmd->changed = true; | |
1425 | ||
1426 | return r; | |
1427 | } | |
1428 | ||
0596661f | 1429 | static int write_hints(struct dm_cache_metadata *cmd, struct dm_cache_policy *policy) |
c6b4fcba JT |
1430 | { |
1431 | int r; | |
1432 | ||
0596661f JT |
1433 | r = begin_hints(cmd, policy); |
1434 | if (r) { | |
1435 | DMERR("begin_hints failed"); | |
1436 | return r; | |
1437 | } | |
1438 | ||
1439 | return policy_walk_mappings(policy, save_hint, cmd); | |
1440 | } | |
1441 | ||
1442 | int dm_cache_write_hints(struct dm_cache_metadata *cmd, struct dm_cache_policy *policy) | |
1443 | { | |
1444 | int r; | |
c6b4fcba | 1445 | |
028ae9f7 | 1446 | WRITE_LOCK(cmd); |
0596661f | 1447 | r = write_hints(cmd, policy); |
028ae9f7 | 1448 | WRITE_UNLOCK(cmd); |
c6b4fcba JT |
1449 | |
1450 | return r; | |
1451 | } | |
2ee57d58 JT |
1452 | |
1453 | int dm_cache_metadata_all_clean(struct dm_cache_metadata *cmd, bool *result) | |
1454 | { | |
d14fcf3d JT |
1455 | int r; |
1456 | ||
1457 | READ_LOCK(cmd); | |
1458 | r = blocks_are_unmapped_or_clean(cmd, 0, cmd->cache_blocks, result); | |
1459 | READ_UNLOCK(cmd); | |
1460 | ||
1461 | return r; | |
2ee57d58 | 1462 | } |
028ae9f7 JT |
1463 | |
1464 | void dm_cache_metadata_set_read_only(struct dm_cache_metadata *cmd) | |
1465 | { | |
1466 | WRITE_LOCK_VOID(cmd); | |
1467 | dm_bm_set_read_only(cmd->bm); | |
1468 | WRITE_UNLOCK(cmd); | |
1469 | } | |
1470 | ||
1471 | void dm_cache_metadata_set_read_write(struct dm_cache_metadata *cmd) | |
1472 | { | |
1473 | WRITE_LOCK_VOID(cmd); | |
1474 | dm_bm_set_read_write(cmd->bm); | |
1475 | WRITE_UNLOCK(cmd); | |
1476 | } | |
1477 | ||
1478 | int dm_cache_metadata_set_needs_check(struct dm_cache_metadata *cmd) | |
1479 | { | |
1480 | int r; | |
1481 | struct dm_block *sblock; | |
1482 | struct cache_disk_superblock *disk_super; | |
1483 | ||
d14fcf3d | 1484 | WRITE_LOCK(cmd); |
028ae9f7 JT |
1485 | set_bit(NEEDS_CHECK, &cmd->flags); |
1486 | ||
1487 | r = superblock_lock(cmd, &sblock); | |
1488 | if (r) { | |
1489 | DMERR("couldn't read superblock"); | |
1490 | goto out; | |
1491 | } | |
1492 | ||
1493 | disk_super = dm_block_data(sblock); | |
1494 | disk_super->flags = cpu_to_le32(cmd->flags); | |
1495 | ||
1496 | dm_bm_unlock(sblock); | |
1497 | ||
1498 | out: | |
d14fcf3d | 1499 | WRITE_UNLOCK(cmd); |
028ae9f7 JT |
1500 | return r; |
1501 | } | |
1502 | ||
d14fcf3d | 1503 | int dm_cache_metadata_needs_check(struct dm_cache_metadata *cmd, bool *result) |
028ae9f7 | 1504 | { |
d14fcf3d JT |
1505 | READ_LOCK(cmd); |
1506 | *result = !!test_bit(NEEDS_CHECK, &cmd->flags); | |
1507 | READ_UNLOCK(cmd); | |
028ae9f7 | 1508 | |
d14fcf3d | 1509 | return 0; |
028ae9f7 JT |
1510 | } |
1511 | ||
1512 | int dm_cache_metadata_abort(struct dm_cache_metadata *cmd) | |
1513 | { | |
1514 | int r; | |
1515 | ||
1516 | WRITE_LOCK(cmd); | |
1517 | __destroy_persistent_data_objects(cmd); | |
1518 | r = __create_persistent_data_objects(cmd, false); | |
1519 | if (r) | |
1520 | cmd->fail_io = true; | |
1521 | WRITE_UNLOCK(cmd); | |
1522 | ||
1523 | return r; | |
1524 | } |