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991d9fa0 JT |
1 | /* |
2 | * Copyright (C) 2011 Red Hat, Inc. | |
3 | * | |
4 | * This file is released under the GPL. | |
5 | */ | |
6 | ||
7 | #include "dm-thin-metadata.h" | |
8 | #include "persistent-data/dm-btree.h" | |
9 | #include "persistent-data/dm-space-map.h" | |
10 | #include "persistent-data/dm-space-map-disk.h" | |
11 | #include "persistent-data/dm-transaction-manager.h" | |
12 | ||
13 | #include <linux/list.h> | |
14 | #include <linux/device-mapper.h> | |
15 | #include <linux/workqueue.h> | |
16 | ||
17 | /*-------------------------------------------------------------------------- | |
18 | * As far as the metadata goes, there is: | |
19 | * | |
20 | * - A superblock in block zero, taking up fewer than 512 bytes for | |
21 | * atomic writes. | |
22 | * | |
23 | * - A space map managing the metadata blocks. | |
24 | * | |
25 | * - A space map managing the data blocks. | |
26 | * | |
27 | * - A btree mapping our internal thin dev ids onto struct disk_device_details. | |
28 | * | |
29 | * - A hierarchical btree, with 2 levels which effectively maps (thin | |
30 | * dev id, virtual block) -> block_time. Block time is a 64-bit | |
31 | * field holding the time in the low 24 bits, and block in the top 48 | |
32 | * bits. | |
33 | * | |
34 | * BTrees consist solely of btree_nodes, that fill a block. Some are | |
35 | * internal nodes, as such their values are a __le64 pointing to other | |
36 | * nodes. Leaf nodes can store data of any reasonable size (ie. much | |
37 | * smaller than the block size). The nodes consist of the header, | |
38 | * followed by an array of keys, followed by an array of values. We have | |
39 | * to binary search on the keys so they're all held together to help the | |
40 | * cpu cache. | |
41 | * | |
42 | * Space maps have 2 btrees: | |
43 | * | |
44 | * - One maps a uint64_t onto a struct index_entry. Which points to a | |
45 | * bitmap block, and has some details about how many free entries there | |
46 | * are etc. | |
47 | * | |
48 | * - The bitmap blocks have a header (for the checksum). Then the rest | |
49 | * of the block is pairs of bits. With the meaning being: | |
50 | * | |
51 | * 0 - ref count is 0 | |
52 | * 1 - ref count is 1 | |
53 | * 2 - ref count is 2 | |
54 | * 3 - ref count is higher than 2 | |
55 | * | |
56 | * - If the count is higher than 2 then the ref count is entered in a | |
57 | * second btree that directly maps the block_address to a uint32_t ref | |
58 | * count. | |
59 | * | |
60 | * The space map metadata variant doesn't have a bitmaps btree. Instead | |
61 | * it has one single blocks worth of index_entries. This avoids | |
62 | * recursive issues with the bitmap btree needing to allocate space in | |
63 | * order to insert. With a small data block size such as 64k the | |
64 | * metadata support data devices that are hundreds of terrabytes. | |
65 | * | |
66 | * The space maps allocate space linearly from front to back. Space that | |
67 | * is freed in a transaction is never recycled within that transaction. | |
68 | * To try and avoid fragmenting _free_ space the allocator always goes | |
69 | * back and fills in gaps. | |
70 | * | |
71 | * All metadata io is in THIN_METADATA_BLOCK_SIZE sized/aligned chunks | |
72 | * from the block manager. | |
73 | *--------------------------------------------------------------------------*/ | |
74 | ||
75 | #define DM_MSG_PREFIX "thin metadata" | |
76 | ||
77 | #define THIN_SUPERBLOCK_MAGIC 27022010 | |
78 | #define THIN_SUPERBLOCK_LOCATION 0 | |
79 | #define THIN_VERSION 1 | |
80 | #define THIN_METADATA_CACHE_SIZE 64 | |
81 | #define SECTOR_TO_BLOCK_SHIFT 3 | |
82 | ||
8c971178 JT |
83 | /* |
84 | * 3 for btree insert + | |
85 | * 2 for btree lookup used within space map | |
86 | */ | |
87 | #define THIN_MAX_CONCURRENT_LOCKS 5 | |
88 | ||
991d9fa0 JT |
89 | /* This should be plenty */ |
90 | #define SPACE_MAP_ROOT_SIZE 128 | |
91 | ||
92 | /* | |
93 | * Little endian on-disk superblock and device details. | |
94 | */ | |
95 | struct thin_disk_superblock { | |
96 | __le32 csum; /* Checksum of superblock except for this field. */ | |
97 | __le32 flags; | |
98 | __le64 blocknr; /* This block number, dm_block_t. */ | |
99 | ||
100 | __u8 uuid[16]; | |
101 | __le64 magic; | |
102 | __le32 version; | |
103 | __le32 time; | |
104 | ||
105 | __le64 trans_id; | |
106 | ||
107 | /* | |
108 | * Root held by userspace transactions. | |
109 | */ | |
110 | __le64 held_root; | |
111 | ||
112 | __u8 data_space_map_root[SPACE_MAP_ROOT_SIZE]; | |
113 | __u8 metadata_space_map_root[SPACE_MAP_ROOT_SIZE]; | |
114 | ||
115 | /* | |
116 | * 2-level btree mapping (dev_id, (dev block, time)) -> data block | |
117 | */ | |
118 | __le64 data_mapping_root; | |
119 | ||
120 | /* | |
121 | * Device detail root mapping dev_id -> device_details | |
122 | */ | |
123 | __le64 device_details_root; | |
124 | ||
125 | __le32 data_block_size; /* In 512-byte sectors. */ | |
126 | ||
127 | __le32 metadata_block_size; /* In 512-byte sectors. */ | |
128 | __le64 metadata_nr_blocks; | |
129 | ||
130 | __le32 compat_flags; | |
131 | __le32 compat_ro_flags; | |
132 | __le32 incompat_flags; | |
133 | } __packed; | |
134 | ||
135 | struct disk_device_details { | |
136 | __le64 mapped_blocks; | |
137 | __le64 transaction_id; /* When created. */ | |
138 | __le32 creation_time; | |
139 | __le32 snapshotted_time; | |
140 | } __packed; | |
141 | ||
142 | struct dm_pool_metadata { | |
143 | struct hlist_node hash; | |
144 | ||
145 | struct block_device *bdev; | |
146 | struct dm_block_manager *bm; | |
147 | struct dm_space_map *metadata_sm; | |
148 | struct dm_space_map *data_sm; | |
149 | struct dm_transaction_manager *tm; | |
150 | struct dm_transaction_manager *nb_tm; | |
151 | ||
152 | /* | |
153 | * Two-level btree. | |
154 | * First level holds thin_dev_t. | |
155 | * Second level holds mappings. | |
156 | */ | |
157 | struct dm_btree_info info; | |
158 | ||
159 | /* | |
160 | * Non-blocking version of the above. | |
161 | */ | |
162 | struct dm_btree_info nb_info; | |
163 | ||
164 | /* | |
165 | * Just the top level for deleting whole devices. | |
166 | */ | |
167 | struct dm_btree_info tl_info; | |
168 | ||
169 | /* | |
170 | * Just the bottom level for creating new devices. | |
171 | */ | |
172 | struct dm_btree_info bl_info; | |
173 | ||
174 | /* | |
175 | * Describes the device details btree. | |
176 | */ | |
177 | struct dm_btree_info details_info; | |
178 | ||
179 | struct rw_semaphore root_lock; | |
180 | uint32_t time; | |
991d9fa0 JT |
181 | dm_block_t root; |
182 | dm_block_t details_root; | |
183 | struct list_head thin_devices; | |
184 | uint64_t trans_id; | |
185 | unsigned long flags; | |
186 | sector_t data_block_size; | |
187 | }; | |
188 | ||
189 | struct dm_thin_device { | |
190 | struct list_head list; | |
191 | struct dm_pool_metadata *pmd; | |
192 | dm_thin_id id; | |
193 | ||
194 | int open_count; | |
195 | int changed; | |
196 | uint64_t mapped_blocks; | |
197 | uint64_t transaction_id; | |
198 | uint32_t creation_time; | |
199 | uint32_t snapshotted_time; | |
200 | }; | |
201 | ||
202 | /*---------------------------------------------------------------- | |
203 | * superblock validator | |
204 | *--------------------------------------------------------------*/ | |
205 | ||
206 | #define SUPERBLOCK_CSUM_XOR 160774 | |
207 | ||
208 | static void sb_prepare_for_write(struct dm_block_validator *v, | |
209 | struct dm_block *b, | |
210 | size_t block_size) | |
211 | { | |
212 | struct thin_disk_superblock *disk_super = dm_block_data(b); | |
213 | ||
214 | disk_super->blocknr = cpu_to_le64(dm_block_location(b)); | |
215 | disk_super->csum = cpu_to_le32(dm_bm_checksum(&disk_super->flags, | |
216 | block_size - sizeof(__le32), | |
217 | SUPERBLOCK_CSUM_XOR)); | |
218 | } | |
219 | ||
220 | static int sb_check(struct dm_block_validator *v, | |
221 | struct dm_block *b, | |
222 | size_t block_size) | |
223 | { | |
224 | struct thin_disk_superblock *disk_super = dm_block_data(b); | |
225 | __le32 csum_le; | |
226 | ||
227 | if (dm_block_location(b) != le64_to_cpu(disk_super->blocknr)) { | |
228 | DMERR("sb_check failed: blocknr %llu: " | |
229 | "wanted %llu", le64_to_cpu(disk_super->blocknr), | |
230 | (unsigned long long)dm_block_location(b)); | |
231 | return -ENOTBLK; | |
232 | } | |
233 | ||
234 | if (le64_to_cpu(disk_super->magic) != THIN_SUPERBLOCK_MAGIC) { | |
235 | DMERR("sb_check failed: magic %llu: " | |
236 | "wanted %llu", le64_to_cpu(disk_super->magic), | |
237 | (unsigned long long)THIN_SUPERBLOCK_MAGIC); | |
238 | return -EILSEQ; | |
239 | } | |
240 | ||
241 | csum_le = cpu_to_le32(dm_bm_checksum(&disk_super->flags, | |
242 | block_size - sizeof(__le32), | |
243 | SUPERBLOCK_CSUM_XOR)); | |
244 | if (csum_le != disk_super->csum) { | |
245 | DMERR("sb_check failed: csum %u: wanted %u", | |
246 | le32_to_cpu(csum_le), le32_to_cpu(disk_super->csum)); | |
247 | return -EILSEQ; | |
248 | } | |
249 | ||
250 | return 0; | |
251 | } | |
252 | ||
253 | static struct dm_block_validator sb_validator = { | |
254 | .name = "superblock", | |
255 | .prepare_for_write = sb_prepare_for_write, | |
256 | .check = sb_check | |
257 | }; | |
258 | ||
259 | /*---------------------------------------------------------------- | |
260 | * Methods for the btree value types | |
261 | *--------------------------------------------------------------*/ | |
262 | ||
263 | static uint64_t pack_block_time(dm_block_t b, uint32_t t) | |
264 | { | |
265 | return (b << 24) | t; | |
266 | } | |
267 | ||
268 | static void unpack_block_time(uint64_t v, dm_block_t *b, uint32_t *t) | |
269 | { | |
270 | *b = v >> 24; | |
271 | *t = v & ((1 << 24) - 1); | |
272 | } | |
273 | ||
274 | static void data_block_inc(void *context, void *value_le) | |
275 | { | |
276 | struct dm_space_map *sm = context; | |
277 | __le64 v_le; | |
278 | uint64_t b; | |
279 | uint32_t t; | |
280 | ||
281 | memcpy(&v_le, value_le, sizeof(v_le)); | |
282 | unpack_block_time(le64_to_cpu(v_le), &b, &t); | |
283 | dm_sm_inc_block(sm, b); | |
284 | } | |
285 | ||
286 | static void data_block_dec(void *context, void *value_le) | |
287 | { | |
288 | struct dm_space_map *sm = context; | |
289 | __le64 v_le; | |
290 | uint64_t b; | |
291 | uint32_t t; | |
292 | ||
293 | memcpy(&v_le, value_le, sizeof(v_le)); | |
294 | unpack_block_time(le64_to_cpu(v_le), &b, &t); | |
295 | dm_sm_dec_block(sm, b); | |
296 | } | |
297 | ||
298 | static int data_block_equal(void *context, void *value1_le, void *value2_le) | |
299 | { | |
300 | __le64 v1_le, v2_le; | |
301 | uint64_t b1, b2; | |
302 | uint32_t t; | |
303 | ||
304 | memcpy(&v1_le, value1_le, sizeof(v1_le)); | |
305 | memcpy(&v2_le, value2_le, sizeof(v2_le)); | |
306 | unpack_block_time(le64_to_cpu(v1_le), &b1, &t); | |
307 | unpack_block_time(le64_to_cpu(v2_le), &b2, &t); | |
308 | ||
309 | return b1 == b2; | |
310 | } | |
311 | ||
312 | static void subtree_inc(void *context, void *value) | |
313 | { | |
314 | struct dm_btree_info *info = context; | |
315 | __le64 root_le; | |
316 | uint64_t root; | |
317 | ||
318 | memcpy(&root_le, value, sizeof(root_le)); | |
319 | root = le64_to_cpu(root_le); | |
320 | dm_tm_inc(info->tm, root); | |
321 | } | |
322 | ||
323 | static void subtree_dec(void *context, void *value) | |
324 | { | |
325 | struct dm_btree_info *info = context; | |
326 | __le64 root_le; | |
327 | uint64_t root; | |
328 | ||
329 | memcpy(&root_le, value, sizeof(root_le)); | |
330 | root = le64_to_cpu(root_le); | |
331 | if (dm_btree_del(info, root)) | |
332 | DMERR("btree delete failed\n"); | |
333 | } | |
334 | ||
335 | static int subtree_equal(void *context, void *value1_le, void *value2_le) | |
336 | { | |
337 | __le64 v1_le, v2_le; | |
338 | memcpy(&v1_le, value1_le, sizeof(v1_le)); | |
339 | memcpy(&v2_le, value2_le, sizeof(v2_le)); | |
340 | ||
341 | return v1_le == v2_le; | |
342 | } | |
343 | ||
344 | /*----------------------------------------------------------------*/ | |
345 | ||
25971192 JT |
346 | static int superblock_lock_zero(struct dm_pool_metadata *pmd, |
347 | struct dm_block **sblock) | |
348 | { | |
349 | return dm_bm_write_lock_zero(pmd->bm, THIN_SUPERBLOCK_LOCATION, | |
350 | &sb_validator, sblock); | |
351 | } | |
352 | ||
353 | static int superblock_lock(struct dm_pool_metadata *pmd, | |
354 | struct dm_block **sblock) | |
355 | { | |
356 | return dm_bm_write_lock(pmd->bm, THIN_SUPERBLOCK_LOCATION, | |
357 | &sb_validator, sblock); | |
358 | } | |
359 | ||
332627db | 360 | static int __superblock_all_zeroes(struct dm_block_manager *bm, int *result) |
991d9fa0 JT |
361 | { |
362 | int r; | |
363 | unsigned i; | |
364 | struct dm_block *b; | |
365 | __le64 *data_le, zero = cpu_to_le64(0); | |
366 | unsigned block_size = dm_bm_block_size(bm) / sizeof(__le64); | |
367 | ||
368 | /* | |
369 | * We can't use a validator here - it may be all zeroes. | |
370 | */ | |
371 | r = dm_bm_read_lock(bm, THIN_SUPERBLOCK_LOCATION, NULL, &b); | |
372 | if (r) | |
373 | return r; | |
374 | ||
375 | data_le = dm_block_data(b); | |
376 | *result = 1; | |
377 | for (i = 0; i < block_size; i++) { | |
378 | if (data_le[i] != zero) { | |
379 | *result = 0; | |
380 | break; | |
381 | } | |
382 | } | |
383 | ||
384 | return dm_bm_unlock(b); | |
385 | } | |
386 | ||
41675aea JT |
387 | static void __setup_btree_details(struct dm_pool_metadata *pmd) |
388 | { | |
389 | pmd->info.tm = pmd->tm; | |
390 | pmd->info.levels = 2; | |
391 | pmd->info.value_type.context = pmd->data_sm; | |
392 | pmd->info.value_type.size = sizeof(__le64); | |
393 | pmd->info.value_type.inc = data_block_inc; | |
394 | pmd->info.value_type.dec = data_block_dec; | |
395 | pmd->info.value_type.equal = data_block_equal; | |
396 | ||
397 | memcpy(&pmd->nb_info, &pmd->info, sizeof(pmd->nb_info)); | |
398 | pmd->nb_info.tm = pmd->nb_tm; | |
399 | ||
400 | pmd->tl_info.tm = pmd->tm; | |
401 | pmd->tl_info.levels = 1; | |
402 | pmd->tl_info.value_type.context = &pmd->info; | |
403 | pmd->tl_info.value_type.size = sizeof(__le64); | |
404 | pmd->tl_info.value_type.inc = subtree_inc; | |
405 | pmd->tl_info.value_type.dec = subtree_dec; | |
406 | pmd->tl_info.value_type.equal = subtree_equal; | |
407 | ||
408 | pmd->bl_info.tm = pmd->tm; | |
409 | pmd->bl_info.levels = 1; | |
410 | pmd->bl_info.value_type.context = pmd->data_sm; | |
411 | pmd->bl_info.value_type.size = sizeof(__le64); | |
412 | pmd->bl_info.value_type.inc = data_block_inc; | |
413 | pmd->bl_info.value_type.dec = data_block_dec; | |
414 | pmd->bl_info.value_type.equal = data_block_equal; | |
415 | ||
416 | pmd->details_info.tm = pmd->tm; | |
417 | pmd->details_info.levels = 1; | |
418 | pmd->details_info.value_type.context = NULL; | |
419 | pmd->details_info.value_type.size = sizeof(struct disk_device_details); | |
420 | pmd->details_info.value_type.inc = NULL; | |
421 | pmd->details_info.value_type.dec = NULL; | |
422 | pmd->details_info.value_type.equal = NULL; | |
423 | } | |
424 | ||
332627db JT |
425 | static int __open_or_format_metadata(struct dm_pool_metadata *pmd, |
426 | struct dm_block_manager *bm, | |
427 | dm_block_t nr_blocks, int create) | |
991d9fa0 JT |
428 | { |
429 | int r; | |
430 | struct dm_space_map *sm, *data_sm; | |
431 | struct dm_transaction_manager *tm; | |
432 | struct dm_block *sblock; | |
433 | ||
434 | if (create) { | |
384ef0e6 | 435 | r = dm_tm_create_with_sm(bm, THIN_SUPERBLOCK_LOCATION, &tm, &sm); |
991d9fa0 JT |
436 | if (r < 0) { |
437 | DMERR("tm_create_with_sm failed"); | |
438 | return r; | |
439 | } | |
440 | ||
441 | data_sm = dm_sm_disk_create(tm, nr_blocks); | |
442 | if (IS_ERR(data_sm)) { | |
443 | DMERR("sm_disk_create failed"); | |
444 | r = PTR_ERR(data_sm); | |
445 | goto bad; | |
446 | } | |
447 | } else { | |
384ef0e6 | 448 | struct thin_disk_superblock *disk_super; |
991d9fa0 | 449 | |
25971192 JT |
450 | r = dm_bm_read_lock(bm, THIN_SUPERBLOCK_LOCATION, |
451 | &sb_validator, &sblock); | |
384ef0e6 JT |
452 | if (r < 0) { |
453 | DMERR("couldn't read superblock"); | |
454 | return r; | |
455 | } | |
456 | ||
457 | disk_super = dm_block_data(sblock); | |
991d9fa0 | 458 | r = dm_tm_open_with_sm(bm, THIN_SUPERBLOCK_LOCATION, |
384ef0e6 JT |
459 | disk_super->metadata_space_map_root, |
460 | sizeof(disk_super->metadata_space_map_root), | |
461 | &tm, &sm); | |
991d9fa0 JT |
462 | if (r < 0) { |
463 | DMERR("tm_open_with_sm failed"); | |
384ef0e6 | 464 | dm_bm_unlock(sblock); |
991d9fa0 JT |
465 | return r; |
466 | } | |
467 | ||
991d9fa0 JT |
468 | data_sm = dm_sm_disk_open(tm, disk_super->data_space_map_root, |
469 | sizeof(disk_super->data_space_map_root)); | |
470 | if (IS_ERR(data_sm)) { | |
471 | DMERR("sm_disk_open failed"); | |
384ef0e6 | 472 | dm_bm_unlock(sblock); |
991d9fa0 JT |
473 | r = PTR_ERR(data_sm); |
474 | goto bad; | |
475 | } | |
991d9fa0 | 476 | |
384ef0e6 | 477 | dm_bm_unlock(sblock); |
991d9fa0 JT |
478 | } |
479 | ||
480 | pmd->bm = bm; | |
481 | pmd->metadata_sm = sm; | |
482 | pmd->data_sm = data_sm; | |
483 | pmd->tm = tm; | |
484 | pmd->nb_tm = dm_tm_create_non_blocking_clone(tm); | |
485 | if (!pmd->nb_tm) { | |
486 | DMERR("could not create clone tm"); | |
487 | r = -ENOMEM; | |
488 | goto bad_data_sm; | |
489 | } | |
490 | ||
41675aea | 491 | __setup_btree_details(pmd); |
991d9fa0 JT |
492 | pmd->root = 0; |
493 | ||
494 | init_rwsem(&pmd->root_lock); | |
495 | pmd->time = 0; | |
991d9fa0 JT |
496 | pmd->details_root = 0; |
497 | pmd->trans_id = 0; | |
498 | pmd->flags = 0; | |
499 | INIT_LIST_HEAD(&pmd->thin_devices); | |
500 | ||
501 | return 0; | |
502 | ||
503 | bad_data_sm: | |
504 | dm_sm_destroy(data_sm); | |
505 | bad: | |
506 | dm_tm_destroy(tm); | |
507 | dm_sm_destroy(sm); | |
508 | ||
509 | return r; | |
510 | } | |
511 | ||
332627db JT |
512 | static int __create_persistent_data_objects(struct dm_pool_metadata *pmd, |
513 | dm_block_t nr_blocks, int *create) | |
514 | { | |
515 | int r; | |
516 | ||
517 | pmd->bm = dm_block_manager_create(pmd->bdev, THIN_METADATA_BLOCK_SIZE, | |
518 | THIN_METADATA_CACHE_SIZE, | |
519 | THIN_MAX_CONCURRENT_LOCKS); | |
520 | if (IS_ERR(pmd->bm)) { | |
521 | DMERR("could not create block manager"); | |
522 | return PTR_ERR(pmd->bm); | |
523 | } | |
524 | ||
525 | r = __superblock_all_zeroes(pmd->bm, create); | |
526 | if (r) { | |
527 | dm_block_manager_destroy(pmd->bm); | |
528 | return r; | |
529 | } | |
530 | ||
531 | r = __open_or_format_metadata(pmd, pmd->bm, nr_blocks, *create); | |
532 | if (r) | |
533 | dm_block_manager_destroy(pmd->bm); | |
534 | ||
535 | return r; | |
536 | } | |
537 | ||
f9dd9352 JT |
538 | static void __destroy_persistent_data_objects(struct dm_pool_metadata *pmd) |
539 | { | |
540 | dm_sm_destroy(pmd->data_sm); | |
541 | dm_sm_destroy(pmd->metadata_sm); | |
542 | dm_tm_destroy(pmd->nb_tm); | |
543 | dm_tm_destroy(pmd->tm); | |
544 | dm_block_manager_destroy(pmd->bm); | |
545 | } | |
546 | ||
991d9fa0 JT |
547 | static int __begin_transaction(struct dm_pool_metadata *pmd) |
548 | { | |
549 | int r; | |
550 | u32 features; | |
551 | struct thin_disk_superblock *disk_super; | |
552 | struct dm_block *sblock; | |
553 | ||
991d9fa0 JT |
554 | /* |
555 | * We re-read the superblock every time. Shouldn't need to do this | |
556 | * really. | |
557 | */ | |
558 | r = dm_bm_read_lock(pmd->bm, THIN_SUPERBLOCK_LOCATION, | |
559 | &sb_validator, &sblock); | |
560 | if (r) | |
561 | return r; | |
562 | ||
563 | disk_super = dm_block_data(sblock); | |
564 | pmd->time = le32_to_cpu(disk_super->time); | |
565 | pmd->root = le64_to_cpu(disk_super->data_mapping_root); | |
566 | pmd->details_root = le64_to_cpu(disk_super->device_details_root); | |
567 | pmd->trans_id = le64_to_cpu(disk_super->trans_id); | |
568 | pmd->flags = le32_to_cpu(disk_super->flags); | |
569 | pmd->data_block_size = le32_to_cpu(disk_super->data_block_size); | |
570 | ||
571 | features = le32_to_cpu(disk_super->incompat_flags) & ~THIN_FEATURE_INCOMPAT_SUPP; | |
572 | if (features) { | |
573 | DMERR("could not access metadata due to " | |
574 | "unsupported optional features (%lx).", | |
575 | (unsigned long)features); | |
576 | r = -EINVAL; | |
577 | goto out; | |
578 | } | |
579 | ||
580 | /* | |
581 | * Check for read-only metadata to skip the following RDWR checks. | |
582 | */ | |
583 | if (get_disk_ro(pmd->bdev->bd_disk)) | |
584 | goto out; | |
585 | ||
586 | features = le32_to_cpu(disk_super->compat_ro_flags) & ~THIN_FEATURE_COMPAT_RO_SUPP; | |
587 | if (features) { | |
588 | DMERR("could not access metadata RDWR due to " | |
589 | "unsupported optional features (%lx).", | |
590 | (unsigned long)features); | |
591 | r = -EINVAL; | |
592 | } | |
593 | ||
594 | out: | |
595 | dm_bm_unlock(sblock); | |
596 | return r; | |
597 | } | |
598 | ||
599 | static int __write_changed_details(struct dm_pool_metadata *pmd) | |
600 | { | |
601 | int r; | |
602 | struct dm_thin_device *td, *tmp; | |
603 | struct disk_device_details details; | |
604 | uint64_t key; | |
605 | ||
606 | list_for_each_entry_safe(td, tmp, &pmd->thin_devices, list) { | |
607 | if (!td->changed) | |
608 | continue; | |
609 | ||
610 | key = td->id; | |
611 | ||
612 | details.mapped_blocks = cpu_to_le64(td->mapped_blocks); | |
613 | details.transaction_id = cpu_to_le64(td->transaction_id); | |
614 | details.creation_time = cpu_to_le32(td->creation_time); | |
615 | details.snapshotted_time = cpu_to_le32(td->snapshotted_time); | |
616 | __dm_bless_for_disk(&details); | |
617 | ||
618 | r = dm_btree_insert(&pmd->details_info, pmd->details_root, | |
619 | &key, &details, &pmd->details_root); | |
620 | if (r) | |
621 | return r; | |
622 | ||
623 | if (td->open_count) | |
624 | td->changed = 0; | |
625 | else { | |
626 | list_del(&td->list); | |
627 | kfree(td); | |
628 | } | |
991d9fa0 JT |
629 | } |
630 | ||
631 | return 0; | |
632 | } | |
633 | ||
634 | static int __commit_transaction(struct dm_pool_metadata *pmd) | |
635 | { | |
636 | /* | |
637 | * FIXME: Associated pool should be made read-only on failure. | |
638 | */ | |
639 | int r; | |
640 | size_t metadata_len, data_len; | |
641 | struct thin_disk_superblock *disk_super; | |
642 | struct dm_block *sblock; | |
643 | ||
644 | /* | |
645 | * We need to know if the thin_disk_superblock exceeds a 512-byte sector. | |
646 | */ | |
647 | BUILD_BUG_ON(sizeof(struct thin_disk_superblock) > 512); | |
648 | ||
649 | r = __write_changed_details(pmd); | |
650 | if (r < 0) | |
d973ac19 | 651 | return r; |
991d9fa0 | 652 | |
991d9fa0 JT |
653 | r = dm_sm_commit(pmd->data_sm); |
654 | if (r < 0) | |
d973ac19 | 655 | return r; |
991d9fa0 JT |
656 | |
657 | r = dm_tm_pre_commit(pmd->tm); | |
658 | if (r < 0) | |
d973ac19 | 659 | return r; |
991d9fa0 JT |
660 | |
661 | r = dm_sm_root_size(pmd->metadata_sm, &metadata_len); | |
662 | if (r < 0) | |
d973ac19 | 663 | return r; |
991d9fa0 | 664 | |
fef838cc | 665 | r = dm_sm_root_size(pmd->data_sm, &data_len); |
991d9fa0 | 666 | if (r < 0) |
d973ac19 | 667 | return r; |
991d9fa0 | 668 | |
25971192 | 669 | r = superblock_lock(pmd, &sblock); |
991d9fa0 | 670 | if (r) |
d973ac19 | 671 | return r; |
991d9fa0 JT |
672 | |
673 | disk_super = dm_block_data(sblock); | |
674 | disk_super->time = cpu_to_le32(pmd->time); | |
675 | disk_super->data_mapping_root = cpu_to_le64(pmd->root); | |
676 | disk_super->device_details_root = cpu_to_le64(pmd->details_root); | |
677 | disk_super->trans_id = cpu_to_le64(pmd->trans_id); | |
678 | disk_super->flags = cpu_to_le32(pmd->flags); | |
679 | ||
680 | r = dm_sm_copy_root(pmd->metadata_sm, &disk_super->metadata_space_map_root, | |
681 | metadata_len); | |
682 | if (r < 0) | |
683 | goto out_locked; | |
684 | ||
685 | r = dm_sm_copy_root(pmd->data_sm, &disk_super->data_space_map_root, | |
686 | data_len); | |
687 | if (r < 0) | |
688 | goto out_locked; | |
689 | ||
eb04cf63 | 690 | return dm_tm_commit(pmd->tm, sblock); |
991d9fa0 JT |
691 | |
692 | out_locked: | |
693 | dm_bm_unlock(sblock); | |
694 | return r; | |
695 | } | |
696 | ||
697 | struct dm_pool_metadata *dm_pool_metadata_open(struct block_device *bdev, | |
698 | sector_t data_block_size) | |
699 | { | |
700 | int r; | |
701 | struct thin_disk_superblock *disk_super; | |
702 | struct dm_pool_metadata *pmd; | |
703 | sector_t bdev_size = i_size_read(bdev->bd_inode) >> SECTOR_SHIFT; | |
991d9fa0 JT |
704 | int create; |
705 | struct dm_block *sblock; | |
706 | ||
707 | pmd = kmalloc(sizeof(*pmd), GFP_KERNEL); | |
708 | if (!pmd) { | |
709 | DMERR("could not allocate metadata struct"); | |
710 | return ERR_PTR(-ENOMEM); | |
711 | } | |
712 | ||
332627db | 713 | pmd->bdev = bdev; |
991d9fa0 | 714 | |
332627db | 715 | r = __create_persistent_data_objects(pmd, 0, &create); |
991d9fa0 | 716 | if (r) { |
991d9fa0 JT |
717 | kfree(pmd); |
718 | return ERR_PTR(r); | |
719 | } | |
991d9fa0 JT |
720 | |
721 | if (!create) { | |
722 | r = __begin_transaction(pmd); | |
723 | if (r < 0) | |
724 | goto bad; | |
725 | return pmd; | |
726 | } | |
727 | ||
728 | /* | |
729 | * Create. | |
730 | */ | |
25971192 | 731 | r = superblock_lock_zero(pmd, &sblock); |
991d9fa0 JT |
732 | if (r) |
733 | goto bad; | |
734 | ||
c4a69ecd MS |
735 | if (bdev_size > THIN_METADATA_MAX_SECTORS) |
736 | bdev_size = THIN_METADATA_MAX_SECTORS; | |
737 | ||
991d9fa0 JT |
738 | disk_super = dm_block_data(sblock); |
739 | disk_super->magic = cpu_to_le64(THIN_SUPERBLOCK_MAGIC); | |
740 | disk_super->version = cpu_to_le32(THIN_VERSION); | |
741 | disk_super->time = 0; | |
742 | disk_super->metadata_block_size = cpu_to_le32(THIN_METADATA_BLOCK_SIZE >> SECTOR_SHIFT); | |
743 | disk_super->metadata_nr_blocks = cpu_to_le64(bdev_size >> SECTOR_TO_BLOCK_SHIFT); | |
744 | disk_super->data_block_size = cpu_to_le32(data_block_size); | |
745 | ||
746 | r = dm_bm_unlock(sblock); | |
747 | if (r < 0) | |
748 | goto bad; | |
749 | ||
750 | r = dm_btree_empty(&pmd->info, &pmd->root); | |
751 | if (r < 0) | |
752 | goto bad; | |
753 | ||
754 | r = dm_btree_empty(&pmd->details_info, &pmd->details_root); | |
755 | if (r < 0) { | |
756 | DMERR("couldn't create devices root"); | |
757 | goto bad; | |
758 | } | |
759 | ||
760 | pmd->flags = 0; | |
991d9fa0 JT |
761 | r = dm_pool_commit_metadata(pmd); |
762 | if (r < 0) { | |
763 | DMERR("%s: dm_pool_commit_metadata() failed, error = %d", | |
764 | __func__, r); | |
765 | goto bad; | |
766 | } | |
767 | ||
768 | return pmd; | |
769 | ||
770 | bad: | |
771 | if (dm_pool_metadata_close(pmd) < 0) | |
772 | DMWARN("%s: dm_pool_metadata_close() failed.", __func__); | |
773 | return ERR_PTR(r); | |
774 | } | |
775 | ||
776 | int dm_pool_metadata_close(struct dm_pool_metadata *pmd) | |
777 | { | |
778 | int r; | |
779 | unsigned open_devices = 0; | |
780 | struct dm_thin_device *td, *tmp; | |
781 | ||
782 | down_read(&pmd->root_lock); | |
783 | list_for_each_entry_safe(td, tmp, &pmd->thin_devices, list) { | |
784 | if (td->open_count) | |
785 | open_devices++; | |
786 | else { | |
787 | list_del(&td->list); | |
788 | kfree(td); | |
789 | } | |
790 | } | |
791 | up_read(&pmd->root_lock); | |
792 | ||
793 | if (open_devices) { | |
794 | DMERR("attempt to close pmd when %u device(s) are still open", | |
795 | open_devices); | |
796 | return -EBUSY; | |
797 | } | |
798 | ||
799 | r = __commit_transaction(pmd); | |
800 | if (r < 0) | |
801 | DMWARN("%s: __commit_transaction() failed, error = %d", | |
802 | __func__, r); | |
803 | ||
f9dd9352 | 804 | __destroy_persistent_data_objects(pmd); |
991d9fa0 JT |
805 | kfree(pmd); |
806 | ||
807 | return 0; | |
808 | } | |
809 | ||
1f3db25d MS |
810 | /* |
811 | * __open_device: Returns @td corresponding to device with id @dev, | |
812 | * creating it if @create is set and incrementing @td->open_count. | |
813 | * On failure, @td is undefined. | |
814 | */ | |
991d9fa0 JT |
815 | static int __open_device(struct dm_pool_metadata *pmd, |
816 | dm_thin_id dev, int create, | |
817 | struct dm_thin_device **td) | |
818 | { | |
819 | int r, changed = 0; | |
820 | struct dm_thin_device *td2; | |
821 | uint64_t key = dev; | |
822 | struct disk_device_details details_le; | |
823 | ||
824 | /* | |
1f3db25d | 825 | * If the device is already open, return it. |
991d9fa0 JT |
826 | */ |
827 | list_for_each_entry(td2, &pmd->thin_devices, list) | |
828 | if (td2->id == dev) { | |
1f3db25d MS |
829 | /* |
830 | * May not create an already-open device. | |
831 | */ | |
832 | if (create) | |
833 | return -EEXIST; | |
834 | ||
991d9fa0 JT |
835 | td2->open_count++; |
836 | *td = td2; | |
837 | return 0; | |
838 | } | |
839 | ||
840 | /* | |
841 | * Check the device exists. | |
842 | */ | |
843 | r = dm_btree_lookup(&pmd->details_info, pmd->details_root, | |
844 | &key, &details_le); | |
845 | if (r) { | |
846 | if (r != -ENODATA || !create) | |
847 | return r; | |
848 | ||
1f3db25d MS |
849 | /* |
850 | * Create new device. | |
851 | */ | |
991d9fa0 JT |
852 | changed = 1; |
853 | details_le.mapped_blocks = 0; | |
854 | details_le.transaction_id = cpu_to_le64(pmd->trans_id); | |
855 | details_le.creation_time = cpu_to_le32(pmd->time); | |
856 | details_le.snapshotted_time = cpu_to_le32(pmd->time); | |
857 | } | |
858 | ||
859 | *td = kmalloc(sizeof(**td), GFP_NOIO); | |
860 | if (!*td) | |
861 | return -ENOMEM; | |
862 | ||
863 | (*td)->pmd = pmd; | |
864 | (*td)->id = dev; | |
865 | (*td)->open_count = 1; | |
866 | (*td)->changed = changed; | |
867 | (*td)->mapped_blocks = le64_to_cpu(details_le.mapped_blocks); | |
868 | (*td)->transaction_id = le64_to_cpu(details_le.transaction_id); | |
869 | (*td)->creation_time = le32_to_cpu(details_le.creation_time); | |
870 | (*td)->snapshotted_time = le32_to_cpu(details_le.snapshotted_time); | |
871 | ||
872 | list_add(&(*td)->list, &pmd->thin_devices); | |
873 | ||
874 | return 0; | |
875 | } | |
876 | ||
877 | static void __close_device(struct dm_thin_device *td) | |
878 | { | |
879 | --td->open_count; | |
880 | } | |
881 | ||
882 | static int __create_thin(struct dm_pool_metadata *pmd, | |
883 | dm_thin_id dev) | |
884 | { | |
885 | int r; | |
886 | dm_block_t dev_root; | |
887 | uint64_t key = dev; | |
888 | struct disk_device_details details_le; | |
889 | struct dm_thin_device *td; | |
890 | __le64 value; | |
891 | ||
892 | r = dm_btree_lookup(&pmd->details_info, pmd->details_root, | |
893 | &key, &details_le); | |
894 | if (!r) | |
895 | return -EEXIST; | |
896 | ||
897 | /* | |
898 | * Create an empty btree for the mappings. | |
899 | */ | |
900 | r = dm_btree_empty(&pmd->bl_info, &dev_root); | |
901 | if (r) | |
902 | return r; | |
903 | ||
904 | /* | |
905 | * Insert it into the main mapping tree. | |
906 | */ | |
907 | value = cpu_to_le64(dev_root); | |
908 | __dm_bless_for_disk(&value); | |
909 | r = dm_btree_insert(&pmd->tl_info, pmd->root, &key, &value, &pmd->root); | |
910 | if (r) { | |
911 | dm_btree_del(&pmd->bl_info, dev_root); | |
912 | return r; | |
913 | } | |
914 | ||
915 | r = __open_device(pmd, dev, 1, &td); | |
916 | if (r) { | |
991d9fa0 JT |
917 | dm_btree_remove(&pmd->tl_info, pmd->root, &key, &pmd->root); |
918 | dm_btree_del(&pmd->bl_info, dev_root); | |
919 | return r; | |
920 | } | |
991d9fa0 JT |
921 | __close_device(td); |
922 | ||
923 | return r; | |
924 | } | |
925 | ||
926 | int dm_pool_create_thin(struct dm_pool_metadata *pmd, dm_thin_id dev) | |
927 | { | |
928 | int r; | |
929 | ||
930 | down_write(&pmd->root_lock); | |
931 | r = __create_thin(pmd, dev); | |
932 | up_write(&pmd->root_lock); | |
933 | ||
934 | return r; | |
935 | } | |
936 | ||
937 | static int __set_snapshot_details(struct dm_pool_metadata *pmd, | |
938 | struct dm_thin_device *snap, | |
939 | dm_thin_id origin, uint32_t time) | |
940 | { | |
941 | int r; | |
942 | struct dm_thin_device *td; | |
943 | ||
944 | r = __open_device(pmd, origin, 0, &td); | |
945 | if (r) | |
946 | return r; | |
947 | ||
948 | td->changed = 1; | |
949 | td->snapshotted_time = time; | |
950 | ||
951 | snap->mapped_blocks = td->mapped_blocks; | |
952 | snap->snapshotted_time = time; | |
953 | __close_device(td); | |
954 | ||
955 | return 0; | |
956 | } | |
957 | ||
958 | static int __create_snap(struct dm_pool_metadata *pmd, | |
959 | dm_thin_id dev, dm_thin_id origin) | |
960 | { | |
961 | int r; | |
962 | dm_block_t origin_root; | |
963 | uint64_t key = origin, dev_key = dev; | |
964 | struct dm_thin_device *td; | |
965 | struct disk_device_details details_le; | |
966 | __le64 value; | |
967 | ||
968 | /* check this device is unused */ | |
969 | r = dm_btree_lookup(&pmd->details_info, pmd->details_root, | |
970 | &dev_key, &details_le); | |
971 | if (!r) | |
972 | return -EEXIST; | |
973 | ||
974 | /* find the mapping tree for the origin */ | |
975 | r = dm_btree_lookup(&pmd->tl_info, pmd->root, &key, &value); | |
976 | if (r) | |
977 | return r; | |
978 | origin_root = le64_to_cpu(value); | |
979 | ||
980 | /* clone the origin, an inc will do */ | |
981 | dm_tm_inc(pmd->tm, origin_root); | |
982 | ||
983 | /* insert into the main mapping tree */ | |
984 | value = cpu_to_le64(origin_root); | |
985 | __dm_bless_for_disk(&value); | |
986 | key = dev; | |
987 | r = dm_btree_insert(&pmd->tl_info, pmd->root, &key, &value, &pmd->root); | |
988 | if (r) { | |
989 | dm_tm_dec(pmd->tm, origin_root); | |
990 | return r; | |
991 | } | |
992 | ||
993 | pmd->time++; | |
994 | ||
995 | r = __open_device(pmd, dev, 1, &td); | |
996 | if (r) | |
997 | goto bad; | |
998 | ||
999 | r = __set_snapshot_details(pmd, td, origin, pmd->time); | |
1f3db25d MS |
1000 | __close_device(td); |
1001 | ||
991d9fa0 JT |
1002 | if (r) |
1003 | goto bad; | |
1004 | ||
991d9fa0 JT |
1005 | return 0; |
1006 | ||
1007 | bad: | |
991d9fa0 JT |
1008 | dm_btree_remove(&pmd->tl_info, pmd->root, &key, &pmd->root); |
1009 | dm_btree_remove(&pmd->details_info, pmd->details_root, | |
1010 | &key, &pmd->details_root); | |
1011 | return r; | |
1012 | } | |
1013 | ||
1014 | int dm_pool_create_snap(struct dm_pool_metadata *pmd, | |
1015 | dm_thin_id dev, | |
1016 | dm_thin_id origin) | |
1017 | { | |
1018 | int r; | |
1019 | ||
1020 | down_write(&pmd->root_lock); | |
1021 | r = __create_snap(pmd, dev, origin); | |
1022 | up_write(&pmd->root_lock); | |
1023 | ||
1024 | return r; | |
1025 | } | |
1026 | ||
1027 | static int __delete_device(struct dm_pool_metadata *pmd, dm_thin_id dev) | |
1028 | { | |
1029 | int r; | |
1030 | uint64_t key = dev; | |
1031 | struct dm_thin_device *td; | |
1032 | ||
1033 | /* TODO: failure should mark the transaction invalid */ | |
1034 | r = __open_device(pmd, dev, 0, &td); | |
1035 | if (r) | |
1036 | return r; | |
1037 | ||
1038 | if (td->open_count > 1) { | |
1039 | __close_device(td); | |
1040 | return -EBUSY; | |
1041 | } | |
1042 | ||
1043 | list_del(&td->list); | |
1044 | kfree(td); | |
1045 | r = dm_btree_remove(&pmd->details_info, pmd->details_root, | |
1046 | &key, &pmd->details_root); | |
1047 | if (r) | |
1048 | return r; | |
1049 | ||
1050 | r = dm_btree_remove(&pmd->tl_info, pmd->root, &key, &pmd->root); | |
1051 | if (r) | |
1052 | return r; | |
1053 | ||
991d9fa0 JT |
1054 | return 0; |
1055 | } | |
1056 | ||
1057 | int dm_pool_delete_thin_device(struct dm_pool_metadata *pmd, | |
1058 | dm_thin_id dev) | |
1059 | { | |
1060 | int r; | |
1061 | ||
1062 | down_write(&pmd->root_lock); | |
1063 | r = __delete_device(pmd, dev); | |
1064 | up_write(&pmd->root_lock); | |
1065 | ||
1066 | return r; | |
1067 | } | |
1068 | ||
1069 | int dm_pool_set_metadata_transaction_id(struct dm_pool_metadata *pmd, | |
1070 | uint64_t current_id, | |
1071 | uint64_t new_id) | |
1072 | { | |
1073 | down_write(&pmd->root_lock); | |
1074 | if (pmd->trans_id != current_id) { | |
1075 | up_write(&pmd->root_lock); | |
1076 | DMERR("mismatched transaction id"); | |
1077 | return -EINVAL; | |
1078 | } | |
1079 | ||
1080 | pmd->trans_id = new_id; | |
991d9fa0 JT |
1081 | up_write(&pmd->root_lock); |
1082 | ||
1083 | return 0; | |
1084 | } | |
1085 | ||
1086 | int dm_pool_get_metadata_transaction_id(struct dm_pool_metadata *pmd, | |
1087 | uint64_t *result) | |
1088 | { | |
1089 | down_read(&pmd->root_lock); | |
1090 | *result = pmd->trans_id; | |
1091 | up_read(&pmd->root_lock); | |
1092 | ||
1093 | return 0; | |
1094 | } | |
1095 | ||
cc8394d8 JT |
1096 | static int __reserve_metadata_snap(struct dm_pool_metadata *pmd) |
1097 | { | |
1098 | int r, inc; | |
1099 | struct thin_disk_superblock *disk_super; | |
1100 | struct dm_block *copy, *sblock; | |
1101 | dm_block_t held_root; | |
1102 | ||
1103 | /* | |
1104 | * Copy the superblock. | |
1105 | */ | |
1106 | dm_sm_inc_block(pmd->metadata_sm, THIN_SUPERBLOCK_LOCATION); | |
1107 | r = dm_tm_shadow_block(pmd->tm, THIN_SUPERBLOCK_LOCATION, | |
1108 | &sb_validator, ©, &inc); | |
1109 | if (r) | |
1110 | return r; | |
1111 | ||
1112 | BUG_ON(!inc); | |
1113 | ||
1114 | held_root = dm_block_location(copy); | |
1115 | disk_super = dm_block_data(copy); | |
1116 | ||
1117 | if (le64_to_cpu(disk_super->held_root)) { | |
1118 | DMWARN("Pool metadata snapshot already exists: release this before taking another."); | |
1119 | ||
1120 | dm_tm_dec(pmd->tm, held_root); | |
1121 | dm_tm_unlock(pmd->tm, copy); | |
cc8394d8 JT |
1122 | return -EBUSY; |
1123 | } | |
1124 | ||
1125 | /* | |
1126 | * Wipe the spacemap since we're not publishing this. | |
1127 | */ | |
1128 | memset(&disk_super->data_space_map_root, 0, | |
1129 | sizeof(disk_super->data_space_map_root)); | |
1130 | memset(&disk_super->metadata_space_map_root, 0, | |
1131 | sizeof(disk_super->metadata_space_map_root)); | |
1132 | ||
1133 | /* | |
1134 | * Increment the data structures that need to be preserved. | |
1135 | */ | |
1136 | dm_tm_inc(pmd->tm, le64_to_cpu(disk_super->data_mapping_root)); | |
1137 | dm_tm_inc(pmd->tm, le64_to_cpu(disk_super->device_details_root)); | |
1138 | dm_tm_unlock(pmd->tm, copy); | |
1139 | ||
1140 | /* | |
1141 | * Write the held root into the superblock. | |
1142 | */ | |
25971192 | 1143 | r = superblock_lock(pmd, &sblock); |
cc8394d8 JT |
1144 | if (r) { |
1145 | dm_tm_dec(pmd->tm, held_root); | |
cc8394d8 JT |
1146 | return r; |
1147 | } | |
1148 | ||
1149 | disk_super = dm_block_data(sblock); | |
1150 | disk_super->held_root = cpu_to_le64(held_root); | |
1151 | dm_bm_unlock(sblock); | |
cc8394d8 JT |
1152 | return 0; |
1153 | } | |
1154 | ||
1155 | int dm_pool_reserve_metadata_snap(struct dm_pool_metadata *pmd) | |
1156 | { | |
1157 | int r; | |
1158 | ||
1159 | down_write(&pmd->root_lock); | |
1160 | r = __reserve_metadata_snap(pmd); | |
1161 | up_write(&pmd->root_lock); | |
1162 | ||
1163 | return r; | |
1164 | } | |
1165 | ||
1166 | static int __release_metadata_snap(struct dm_pool_metadata *pmd) | |
991d9fa0 JT |
1167 | { |
1168 | int r; | |
1169 | struct thin_disk_superblock *disk_super; | |
cc8394d8 JT |
1170 | struct dm_block *sblock, *copy; |
1171 | dm_block_t held_root; | |
991d9fa0 | 1172 | |
25971192 | 1173 | r = superblock_lock(pmd, &sblock); |
991d9fa0 JT |
1174 | if (r) |
1175 | return r; | |
1176 | ||
cc8394d8 JT |
1177 | disk_super = dm_block_data(sblock); |
1178 | held_root = le64_to_cpu(disk_super->held_root); | |
1179 | disk_super->held_root = cpu_to_le64(0); | |
cc8394d8 JT |
1180 | |
1181 | dm_bm_unlock(sblock); | |
1182 | ||
1183 | if (!held_root) { | |
1184 | DMWARN("No pool metadata snapshot found: nothing to release."); | |
1185 | return -EINVAL; | |
1186 | } | |
1187 | ||
1188 | r = dm_tm_read_lock(pmd->tm, held_root, &sb_validator, ©); | |
1189 | if (r) | |
1190 | return r; | |
1191 | ||
1192 | disk_super = dm_block_data(copy); | |
1193 | dm_sm_dec_block(pmd->metadata_sm, le64_to_cpu(disk_super->data_mapping_root)); | |
1194 | dm_sm_dec_block(pmd->metadata_sm, le64_to_cpu(disk_super->device_details_root)); | |
1195 | dm_sm_dec_block(pmd->metadata_sm, held_root); | |
1196 | ||
1197 | return dm_tm_unlock(pmd->tm, copy); | |
1198 | } | |
1199 | ||
1200 | int dm_pool_release_metadata_snap(struct dm_pool_metadata *pmd) | |
1201 | { | |
1202 | int r; | |
1203 | ||
1204 | down_write(&pmd->root_lock); | |
1205 | r = __release_metadata_snap(pmd); | |
1206 | up_write(&pmd->root_lock); | |
1207 | ||
1208 | return r; | |
1209 | } | |
1210 | ||
1211 | static int __get_metadata_snap(struct dm_pool_metadata *pmd, | |
1212 | dm_block_t *result) | |
1213 | { | |
1214 | int r; | |
1215 | struct thin_disk_superblock *disk_super; | |
1216 | struct dm_block *sblock; | |
1217 | ||
1218 | r = dm_bm_read_lock(pmd->bm, THIN_SUPERBLOCK_LOCATION, | |
1219 | &sb_validator, &sblock); | |
1220 | if (r) | |
1221 | return r; | |
1222 | ||
991d9fa0 JT |
1223 | disk_super = dm_block_data(sblock); |
1224 | *result = le64_to_cpu(disk_super->held_root); | |
1225 | ||
1226 | return dm_bm_unlock(sblock); | |
1227 | } | |
1228 | ||
cc8394d8 JT |
1229 | int dm_pool_get_metadata_snap(struct dm_pool_metadata *pmd, |
1230 | dm_block_t *result) | |
991d9fa0 JT |
1231 | { |
1232 | int r; | |
1233 | ||
1234 | down_read(&pmd->root_lock); | |
cc8394d8 | 1235 | r = __get_metadata_snap(pmd, result); |
991d9fa0 JT |
1236 | up_read(&pmd->root_lock); |
1237 | ||
1238 | return r; | |
1239 | } | |
1240 | ||
1241 | int dm_pool_open_thin_device(struct dm_pool_metadata *pmd, dm_thin_id dev, | |
1242 | struct dm_thin_device **td) | |
1243 | { | |
1244 | int r; | |
1245 | ||
1246 | down_write(&pmd->root_lock); | |
1247 | r = __open_device(pmd, dev, 0, td); | |
1248 | up_write(&pmd->root_lock); | |
1249 | ||
1250 | return r; | |
1251 | } | |
1252 | ||
1253 | int dm_pool_close_thin_device(struct dm_thin_device *td) | |
1254 | { | |
1255 | down_write(&td->pmd->root_lock); | |
1256 | __close_device(td); | |
1257 | up_write(&td->pmd->root_lock); | |
1258 | ||
1259 | return 0; | |
1260 | } | |
1261 | ||
1262 | dm_thin_id dm_thin_dev_id(struct dm_thin_device *td) | |
1263 | { | |
1264 | return td->id; | |
1265 | } | |
1266 | ||
17b7d63f | 1267 | static bool __snapshotted_since(struct dm_thin_device *td, uint32_t time) |
991d9fa0 JT |
1268 | { |
1269 | return td->snapshotted_time > time; | |
1270 | } | |
1271 | ||
1272 | int dm_thin_find_block(struct dm_thin_device *td, dm_block_t block, | |
1273 | int can_block, struct dm_thin_lookup_result *result) | |
1274 | { | |
1275 | int r; | |
1276 | uint64_t block_time = 0; | |
1277 | __le64 value; | |
1278 | struct dm_pool_metadata *pmd = td->pmd; | |
1279 | dm_block_t keys[2] = { td->id, block }; | |
1280 | ||
1281 | if (can_block) { | |
1282 | down_read(&pmd->root_lock); | |
1283 | r = dm_btree_lookup(&pmd->info, pmd->root, keys, &value); | |
1284 | if (!r) | |
1285 | block_time = le64_to_cpu(value); | |
1286 | up_read(&pmd->root_lock); | |
1287 | ||
1288 | } else if (down_read_trylock(&pmd->root_lock)) { | |
1289 | r = dm_btree_lookup(&pmd->nb_info, pmd->root, keys, &value); | |
1290 | if (!r) | |
1291 | block_time = le64_to_cpu(value); | |
1292 | up_read(&pmd->root_lock); | |
1293 | ||
1294 | } else | |
1295 | return -EWOULDBLOCK; | |
1296 | ||
1297 | if (!r) { | |
1298 | dm_block_t exception_block; | |
1299 | uint32_t exception_time; | |
1300 | unpack_block_time(block_time, &exception_block, | |
1301 | &exception_time); | |
1302 | result->block = exception_block; | |
1303 | result->shared = __snapshotted_since(td, exception_time); | |
1304 | } | |
1305 | ||
1306 | return r; | |
1307 | } | |
1308 | ||
1309 | static int __insert(struct dm_thin_device *td, dm_block_t block, | |
1310 | dm_block_t data_block) | |
1311 | { | |
1312 | int r, inserted; | |
1313 | __le64 value; | |
1314 | struct dm_pool_metadata *pmd = td->pmd; | |
1315 | dm_block_t keys[2] = { td->id, block }; | |
1316 | ||
991d9fa0 JT |
1317 | value = cpu_to_le64(pack_block_time(data_block, pmd->time)); |
1318 | __dm_bless_for_disk(&value); | |
1319 | ||
1320 | r = dm_btree_insert_notify(&pmd->info, pmd->root, keys, &value, | |
1321 | &pmd->root, &inserted); | |
1322 | if (r) | |
1323 | return r; | |
1324 | ||
1325 | if (inserted) { | |
1326 | td->mapped_blocks++; | |
1327 | td->changed = 1; | |
1328 | } | |
1329 | ||
1330 | return 0; | |
1331 | } | |
1332 | ||
1333 | int dm_thin_insert_block(struct dm_thin_device *td, dm_block_t block, | |
1334 | dm_block_t data_block) | |
1335 | { | |
1336 | int r; | |
1337 | ||
1338 | down_write(&td->pmd->root_lock); | |
1339 | r = __insert(td, block, data_block); | |
1340 | up_write(&td->pmd->root_lock); | |
1341 | ||
1342 | return r; | |
1343 | } | |
1344 | ||
1345 | static int __remove(struct dm_thin_device *td, dm_block_t block) | |
1346 | { | |
1347 | int r; | |
1348 | struct dm_pool_metadata *pmd = td->pmd; | |
1349 | dm_block_t keys[2] = { td->id, block }; | |
1350 | ||
1351 | r = dm_btree_remove(&pmd->info, pmd->root, keys, &pmd->root); | |
1352 | if (r) | |
1353 | return r; | |
1354 | ||
af63bcb8 JT |
1355 | td->mapped_blocks--; |
1356 | td->changed = 1; | |
991d9fa0 JT |
1357 | |
1358 | return 0; | |
1359 | } | |
1360 | ||
1361 | int dm_thin_remove_block(struct dm_thin_device *td, dm_block_t block) | |
1362 | { | |
1363 | int r; | |
1364 | ||
1365 | down_write(&td->pmd->root_lock); | |
1366 | r = __remove(td, block); | |
1367 | up_write(&td->pmd->root_lock); | |
1368 | ||
1369 | return r; | |
1370 | } | |
1371 | ||
1372 | int dm_pool_alloc_data_block(struct dm_pool_metadata *pmd, dm_block_t *result) | |
1373 | { | |
1374 | int r; | |
1375 | ||
1376 | down_write(&pmd->root_lock); | |
991d9fa0 | 1377 | r = dm_sm_new_block(pmd->data_sm, result); |
991d9fa0 JT |
1378 | up_write(&pmd->root_lock); |
1379 | ||
1380 | return r; | |
1381 | } | |
1382 | ||
1383 | int dm_pool_commit_metadata(struct dm_pool_metadata *pmd) | |
1384 | { | |
1385 | int r; | |
1386 | ||
1387 | down_write(&pmd->root_lock); | |
1388 | ||
1389 | r = __commit_transaction(pmd); | |
1390 | if (r <= 0) | |
1391 | goto out; | |
1392 | ||
1393 | /* | |
1394 | * Open the next transaction. | |
1395 | */ | |
1396 | r = __begin_transaction(pmd); | |
1397 | out: | |
1398 | up_write(&pmd->root_lock); | |
1399 | return r; | |
1400 | } | |
1401 | ||
1402 | int dm_pool_get_free_block_count(struct dm_pool_metadata *pmd, dm_block_t *result) | |
1403 | { | |
1404 | int r; | |
1405 | ||
1406 | down_read(&pmd->root_lock); | |
1407 | r = dm_sm_get_nr_free(pmd->data_sm, result); | |
1408 | up_read(&pmd->root_lock); | |
1409 | ||
1410 | return r; | |
1411 | } | |
1412 | ||
1413 | int dm_pool_get_free_metadata_block_count(struct dm_pool_metadata *pmd, | |
1414 | dm_block_t *result) | |
1415 | { | |
1416 | int r; | |
1417 | ||
1418 | down_read(&pmd->root_lock); | |
1419 | r = dm_sm_get_nr_free(pmd->metadata_sm, result); | |
1420 | up_read(&pmd->root_lock); | |
1421 | ||
1422 | return r; | |
1423 | } | |
1424 | ||
1425 | int dm_pool_get_metadata_dev_size(struct dm_pool_metadata *pmd, | |
1426 | dm_block_t *result) | |
1427 | { | |
1428 | int r; | |
1429 | ||
1430 | down_read(&pmd->root_lock); | |
1431 | r = dm_sm_get_nr_blocks(pmd->metadata_sm, result); | |
1432 | up_read(&pmd->root_lock); | |
1433 | ||
1434 | return r; | |
1435 | } | |
1436 | ||
1437 | int dm_pool_get_data_block_size(struct dm_pool_metadata *pmd, sector_t *result) | |
1438 | { | |
1439 | down_read(&pmd->root_lock); | |
1440 | *result = pmd->data_block_size; | |
1441 | up_read(&pmd->root_lock); | |
1442 | ||
1443 | return 0; | |
1444 | } | |
1445 | ||
1446 | int dm_pool_get_data_dev_size(struct dm_pool_metadata *pmd, dm_block_t *result) | |
1447 | { | |
1448 | int r; | |
1449 | ||
1450 | down_read(&pmd->root_lock); | |
1451 | r = dm_sm_get_nr_blocks(pmd->data_sm, result); | |
1452 | up_read(&pmd->root_lock); | |
1453 | ||
1454 | return r; | |
1455 | } | |
1456 | ||
1457 | int dm_thin_get_mapped_count(struct dm_thin_device *td, dm_block_t *result) | |
1458 | { | |
1459 | struct dm_pool_metadata *pmd = td->pmd; | |
1460 | ||
1461 | down_read(&pmd->root_lock); | |
1462 | *result = td->mapped_blocks; | |
1463 | up_read(&pmd->root_lock); | |
1464 | ||
1465 | return 0; | |
1466 | } | |
1467 | ||
1468 | static int __highest_block(struct dm_thin_device *td, dm_block_t *result) | |
1469 | { | |
1470 | int r; | |
1471 | __le64 value_le; | |
1472 | dm_block_t thin_root; | |
1473 | struct dm_pool_metadata *pmd = td->pmd; | |
1474 | ||
1475 | r = dm_btree_lookup(&pmd->tl_info, pmd->root, &td->id, &value_le); | |
1476 | if (r) | |
1477 | return r; | |
1478 | ||
1479 | thin_root = le64_to_cpu(value_le); | |
1480 | ||
1481 | return dm_btree_find_highest_key(&pmd->bl_info, thin_root, result); | |
1482 | } | |
1483 | ||
1484 | int dm_thin_get_highest_mapped_block(struct dm_thin_device *td, | |
1485 | dm_block_t *result) | |
1486 | { | |
1487 | int r; | |
1488 | struct dm_pool_metadata *pmd = td->pmd; | |
1489 | ||
1490 | down_read(&pmd->root_lock); | |
1491 | r = __highest_block(td, result); | |
1492 | up_read(&pmd->root_lock); | |
1493 | ||
1494 | return r; | |
1495 | } | |
1496 | ||
1497 | static int __resize_data_dev(struct dm_pool_metadata *pmd, dm_block_t new_count) | |
1498 | { | |
1499 | int r; | |
1500 | dm_block_t old_count; | |
1501 | ||
1502 | r = dm_sm_get_nr_blocks(pmd->data_sm, &old_count); | |
1503 | if (r) | |
1504 | return r; | |
1505 | ||
1506 | if (new_count == old_count) | |
1507 | return 0; | |
1508 | ||
1509 | if (new_count < old_count) { | |
1510 | DMERR("cannot reduce size of data device"); | |
1511 | return -EINVAL; | |
1512 | } | |
1513 | ||
eb04cf63 | 1514 | return dm_sm_extend(pmd->data_sm, new_count - old_count); |
991d9fa0 JT |
1515 | } |
1516 | ||
1517 | int dm_pool_resize_data_dev(struct dm_pool_metadata *pmd, dm_block_t new_count) | |
1518 | { | |
1519 | int r; | |
1520 | ||
1521 | down_write(&pmd->root_lock); | |
1522 | r = __resize_data_dev(pmd, new_count); | |
1523 | up_write(&pmd->root_lock); | |
1524 | ||
1525 | return r; | |
1526 | } |