Commit | Line | Data |
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991d9fa0 | 1 | /* |
e49e5829 | 2 | * Copyright (C) 2011-2012 Red Hat UK. |
991d9fa0 JT |
3 | * |
4 | * This file is released under the GPL. | |
5 | */ | |
6 | ||
7 | #include "dm-thin-metadata.h" | |
4f81a417 | 8 | #include "dm-bio-prison.h" |
1f4e0ff0 | 9 | #include "dm.h" |
991d9fa0 JT |
10 | |
11 | #include <linux/device-mapper.h> | |
12 | #include <linux/dm-io.h> | |
13 | #include <linux/dm-kcopyd.h> | |
14 | #include <linux/list.h> | |
15 | #include <linux/init.h> | |
16 | #include <linux/module.h> | |
17 | #include <linux/slab.h> | |
18 | ||
19 | #define DM_MSG_PREFIX "thin" | |
20 | ||
21 | /* | |
22 | * Tunable constants | |
23 | */ | |
7768ed33 | 24 | #define ENDIO_HOOK_POOL_SIZE 1024 |
991d9fa0 JT |
25 | #define MAPPING_POOL_SIZE 1024 |
26 | #define PRISON_CELLS 1024 | |
905e51b3 | 27 | #define COMMIT_PERIOD HZ |
991d9fa0 JT |
28 | |
29 | /* | |
30 | * The block size of the device holding pool data must be | |
31 | * between 64KB and 1GB. | |
32 | */ | |
33 | #define DATA_DEV_BLOCK_SIZE_MIN_SECTORS (64 * 1024 >> SECTOR_SHIFT) | |
34 | #define DATA_DEV_BLOCK_SIZE_MAX_SECTORS (1024 * 1024 * 1024 >> SECTOR_SHIFT) | |
35 | ||
991d9fa0 JT |
36 | /* |
37 | * Device id is restricted to 24 bits. | |
38 | */ | |
39 | #define MAX_DEV_ID ((1 << 24) - 1) | |
40 | ||
41 | /* | |
42 | * How do we handle breaking sharing of data blocks? | |
43 | * ================================================= | |
44 | * | |
45 | * We use a standard copy-on-write btree to store the mappings for the | |
46 | * devices (note I'm talking about copy-on-write of the metadata here, not | |
47 | * the data). When you take an internal snapshot you clone the root node | |
48 | * of the origin btree. After this there is no concept of an origin or a | |
49 | * snapshot. They are just two device trees that happen to point to the | |
50 | * same data blocks. | |
51 | * | |
52 | * When we get a write in we decide if it's to a shared data block using | |
53 | * some timestamp magic. If it is, we have to break sharing. | |
54 | * | |
55 | * Let's say we write to a shared block in what was the origin. The | |
56 | * steps are: | |
57 | * | |
58 | * i) plug io further to this physical block. (see bio_prison code). | |
59 | * | |
60 | * ii) quiesce any read io to that shared data block. Obviously | |
44feb387 | 61 | * including all devices that share this block. (see dm_deferred_set code) |
991d9fa0 JT |
62 | * |
63 | * iii) copy the data block to a newly allocate block. This step can be | |
64 | * missed out if the io covers the block. (schedule_copy). | |
65 | * | |
66 | * iv) insert the new mapping into the origin's btree | |
fe878f34 | 67 | * (process_prepared_mapping). This act of inserting breaks some |
991d9fa0 JT |
68 | * sharing of btree nodes between the two devices. Breaking sharing only |
69 | * effects the btree of that specific device. Btrees for the other | |
70 | * devices that share the block never change. The btree for the origin | |
71 | * device as it was after the last commit is untouched, ie. we're using | |
72 | * persistent data structures in the functional programming sense. | |
73 | * | |
74 | * v) unplug io to this physical block, including the io that triggered | |
75 | * the breaking of sharing. | |
76 | * | |
77 | * Steps (ii) and (iii) occur in parallel. | |
78 | * | |
79 | * The metadata _doesn't_ need to be committed before the io continues. We | |
80 | * get away with this because the io is always written to a _new_ block. | |
81 | * If there's a crash, then: | |
82 | * | |
83 | * - The origin mapping will point to the old origin block (the shared | |
84 | * one). This will contain the data as it was before the io that triggered | |
85 | * the breaking of sharing came in. | |
86 | * | |
87 | * - The snap mapping still points to the old block. As it would after | |
88 | * the commit. | |
89 | * | |
90 | * The downside of this scheme is the timestamp magic isn't perfect, and | |
91 | * will continue to think that data block in the snapshot device is shared | |
92 | * even after the write to the origin has broken sharing. I suspect data | |
93 | * blocks will typically be shared by many different devices, so we're | |
94 | * breaking sharing n + 1 times, rather than n, where n is the number of | |
95 | * devices that reference this data block. At the moment I think the | |
96 | * benefits far, far outweigh the disadvantages. | |
97 | */ | |
98 | ||
99 | /*----------------------------------------------------------------*/ | |
100 | ||
991d9fa0 JT |
101 | /* |
102 | * Key building. | |
103 | */ | |
104 | static void build_data_key(struct dm_thin_device *td, | |
44feb387 | 105 | dm_block_t b, struct dm_cell_key *key) |
991d9fa0 JT |
106 | { |
107 | key->virtual = 0; | |
108 | key->dev = dm_thin_dev_id(td); | |
109 | key->block = b; | |
110 | } | |
111 | ||
112 | static void build_virtual_key(struct dm_thin_device *td, dm_block_t b, | |
44feb387 | 113 | struct dm_cell_key *key) |
991d9fa0 JT |
114 | { |
115 | key->virtual = 1; | |
116 | key->dev = dm_thin_dev_id(td); | |
117 | key->block = b; | |
118 | } | |
119 | ||
120 | /*----------------------------------------------------------------*/ | |
121 | ||
122 | /* | |
123 | * A pool device ties together a metadata device and a data device. It | |
124 | * also provides the interface for creating and destroying internal | |
125 | * devices. | |
126 | */ | |
a24c2569 | 127 | struct dm_thin_new_mapping; |
67e2e2b2 | 128 | |
e49e5829 JT |
129 | /* |
130 | * The pool runs in 3 modes. Ordered in degraded order for comparisons. | |
131 | */ | |
132 | enum pool_mode { | |
133 | PM_WRITE, /* metadata may be changed */ | |
134 | PM_READ_ONLY, /* metadata may not be changed */ | |
135 | PM_FAIL, /* all I/O fails */ | |
136 | }; | |
137 | ||
67e2e2b2 | 138 | struct pool_features { |
e49e5829 JT |
139 | enum pool_mode mode; |
140 | ||
9bc142dd MS |
141 | bool zero_new_blocks:1; |
142 | bool discard_enabled:1; | |
143 | bool discard_passdown:1; | |
67e2e2b2 JT |
144 | }; |
145 | ||
e49e5829 JT |
146 | struct thin_c; |
147 | typedef void (*process_bio_fn)(struct thin_c *tc, struct bio *bio); | |
148 | typedef void (*process_mapping_fn)(struct dm_thin_new_mapping *m); | |
149 | ||
991d9fa0 JT |
150 | struct pool { |
151 | struct list_head list; | |
152 | struct dm_target *ti; /* Only set if a pool target is bound */ | |
153 | ||
154 | struct mapped_device *pool_md; | |
155 | struct block_device *md_dev; | |
156 | struct dm_pool_metadata *pmd; | |
157 | ||
991d9fa0 | 158 | dm_block_t low_water_blocks; |
55f2b8bd | 159 | uint32_t sectors_per_block; |
f9a8e0cd | 160 | int sectors_per_block_shift; |
991d9fa0 | 161 | |
67e2e2b2 | 162 | struct pool_features pf; |
991d9fa0 JT |
163 | unsigned low_water_triggered:1; /* A dm event has been sent */ |
164 | unsigned no_free_space:1; /* A -ENOSPC warning has been issued */ | |
165 | ||
44feb387 | 166 | struct dm_bio_prison *prison; |
991d9fa0 JT |
167 | struct dm_kcopyd_client *copier; |
168 | ||
169 | struct workqueue_struct *wq; | |
170 | struct work_struct worker; | |
905e51b3 | 171 | struct delayed_work waker; |
991d9fa0 | 172 | |
905e51b3 | 173 | unsigned long last_commit_jiffies; |
55f2b8bd | 174 | unsigned ref_count; |
991d9fa0 JT |
175 | |
176 | spinlock_t lock; | |
177 | struct bio_list deferred_bios; | |
178 | struct bio_list deferred_flush_bios; | |
179 | struct list_head prepared_mappings; | |
104655fd | 180 | struct list_head prepared_discards; |
991d9fa0 JT |
181 | |
182 | struct bio_list retry_on_resume_list; | |
183 | ||
44feb387 MS |
184 | struct dm_deferred_set *shared_read_ds; |
185 | struct dm_deferred_set *all_io_ds; | |
991d9fa0 | 186 | |
a24c2569 | 187 | struct dm_thin_new_mapping *next_mapping; |
991d9fa0 JT |
188 | mempool_t *mapping_pool; |
189 | mempool_t *endio_hook_pool; | |
e49e5829 JT |
190 | |
191 | process_bio_fn process_bio; | |
192 | process_bio_fn process_discard; | |
193 | ||
194 | process_mapping_fn process_prepared_mapping; | |
195 | process_mapping_fn process_prepared_discard; | |
991d9fa0 JT |
196 | }; |
197 | ||
e49e5829 JT |
198 | static enum pool_mode get_pool_mode(struct pool *pool); |
199 | static void set_pool_mode(struct pool *pool, enum pool_mode mode); | |
200 | ||
991d9fa0 JT |
201 | /* |
202 | * Target context for a pool. | |
203 | */ | |
204 | struct pool_c { | |
205 | struct dm_target *ti; | |
206 | struct pool *pool; | |
207 | struct dm_dev *data_dev; | |
208 | struct dm_dev *metadata_dev; | |
209 | struct dm_target_callbacks callbacks; | |
210 | ||
211 | dm_block_t low_water_blocks; | |
0424caa1 MS |
212 | struct pool_features requested_pf; /* Features requested during table load */ |
213 | struct pool_features adjusted_pf; /* Features used after adjusting for constituent devices */ | |
991d9fa0 JT |
214 | }; |
215 | ||
216 | /* | |
217 | * Target context for a thin. | |
218 | */ | |
219 | struct thin_c { | |
220 | struct dm_dev *pool_dev; | |
2dd9c257 | 221 | struct dm_dev *origin_dev; |
991d9fa0 JT |
222 | dm_thin_id dev_id; |
223 | ||
224 | struct pool *pool; | |
225 | struct dm_thin_device *td; | |
226 | }; | |
227 | ||
228 | /*----------------------------------------------------------------*/ | |
229 | ||
230 | /* | |
231 | * A global list of pools that uses a struct mapped_device as a key. | |
232 | */ | |
233 | static struct dm_thin_pool_table { | |
234 | struct mutex mutex; | |
235 | struct list_head pools; | |
236 | } dm_thin_pool_table; | |
237 | ||
238 | static void pool_table_init(void) | |
239 | { | |
240 | mutex_init(&dm_thin_pool_table.mutex); | |
241 | INIT_LIST_HEAD(&dm_thin_pool_table.pools); | |
242 | } | |
243 | ||
244 | static void __pool_table_insert(struct pool *pool) | |
245 | { | |
246 | BUG_ON(!mutex_is_locked(&dm_thin_pool_table.mutex)); | |
247 | list_add(&pool->list, &dm_thin_pool_table.pools); | |
248 | } | |
249 | ||
250 | static void __pool_table_remove(struct pool *pool) | |
251 | { | |
252 | BUG_ON(!mutex_is_locked(&dm_thin_pool_table.mutex)); | |
253 | list_del(&pool->list); | |
254 | } | |
255 | ||
256 | static struct pool *__pool_table_lookup(struct mapped_device *md) | |
257 | { | |
258 | struct pool *pool = NULL, *tmp; | |
259 | ||
260 | BUG_ON(!mutex_is_locked(&dm_thin_pool_table.mutex)); | |
261 | ||
262 | list_for_each_entry(tmp, &dm_thin_pool_table.pools, list) { | |
263 | if (tmp->pool_md == md) { | |
264 | pool = tmp; | |
265 | break; | |
266 | } | |
267 | } | |
268 | ||
269 | return pool; | |
270 | } | |
271 | ||
272 | static struct pool *__pool_table_lookup_metadata_dev(struct block_device *md_dev) | |
273 | { | |
274 | struct pool *pool = NULL, *tmp; | |
275 | ||
276 | BUG_ON(!mutex_is_locked(&dm_thin_pool_table.mutex)); | |
277 | ||
278 | list_for_each_entry(tmp, &dm_thin_pool_table.pools, list) { | |
279 | if (tmp->md_dev == md_dev) { | |
280 | pool = tmp; | |
281 | break; | |
282 | } | |
283 | } | |
284 | ||
285 | return pool; | |
286 | } | |
287 | ||
288 | /*----------------------------------------------------------------*/ | |
289 | ||
a24c2569 | 290 | struct dm_thin_endio_hook { |
eb2aa48d | 291 | struct thin_c *tc; |
44feb387 MS |
292 | struct dm_deferred_entry *shared_read_entry; |
293 | struct dm_deferred_entry *all_io_entry; | |
a24c2569 | 294 | struct dm_thin_new_mapping *overwrite_mapping; |
eb2aa48d JT |
295 | }; |
296 | ||
991d9fa0 JT |
297 | static void __requeue_bio_list(struct thin_c *tc, struct bio_list *master) |
298 | { | |
299 | struct bio *bio; | |
300 | struct bio_list bios; | |
301 | ||
302 | bio_list_init(&bios); | |
303 | bio_list_merge(&bios, master); | |
304 | bio_list_init(master); | |
305 | ||
306 | while ((bio = bio_list_pop(&bios))) { | |
a24c2569 MS |
307 | struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr; |
308 | ||
eb2aa48d | 309 | if (h->tc == tc) |
991d9fa0 JT |
310 | bio_endio(bio, DM_ENDIO_REQUEUE); |
311 | else | |
312 | bio_list_add(master, bio); | |
313 | } | |
314 | } | |
315 | ||
316 | static void requeue_io(struct thin_c *tc) | |
317 | { | |
318 | struct pool *pool = tc->pool; | |
319 | unsigned long flags; | |
320 | ||
321 | spin_lock_irqsave(&pool->lock, flags); | |
322 | __requeue_bio_list(tc, &pool->deferred_bios); | |
323 | __requeue_bio_list(tc, &pool->retry_on_resume_list); | |
324 | spin_unlock_irqrestore(&pool->lock, flags); | |
325 | } | |
326 | ||
327 | /* | |
328 | * This section of code contains the logic for processing a thin device's IO. | |
329 | * Much of the code depends on pool object resources (lists, workqueues, etc) | |
330 | * but most is exclusively called from the thin target rather than the thin-pool | |
331 | * target. | |
332 | */ | |
333 | ||
334 | static dm_block_t get_bio_block(struct thin_c *tc, struct bio *bio) | |
335 | { | |
55f2b8bd MS |
336 | sector_t block_nr = bio->bi_sector; |
337 | ||
f9a8e0cd MP |
338 | if (tc->pool->sectors_per_block_shift < 0) |
339 | (void) sector_div(block_nr, tc->pool->sectors_per_block); | |
340 | else | |
341 | block_nr >>= tc->pool->sectors_per_block_shift; | |
55f2b8bd MS |
342 | |
343 | return block_nr; | |
991d9fa0 JT |
344 | } |
345 | ||
346 | static void remap(struct thin_c *tc, struct bio *bio, dm_block_t block) | |
347 | { | |
348 | struct pool *pool = tc->pool; | |
55f2b8bd | 349 | sector_t bi_sector = bio->bi_sector; |
991d9fa0 JT |
350 | |
351 | bio->bi_bdev = tc->pool_dev->bdev; | |
f9a8e0cd MP |
352 | if (tc->pool->sectors_per_block_shift < 0) |
353 | bio->bi_sector = (block * pool->sectors_per_block) + | |
354 | sector_div(bi_sector, pool->sectors_per_block); | |
355 | else | |
356 | bio->bi_sector = (block << pool->sectors_per_block_shift) | | |
357 | (bi_sector & (pool->sectors_per_block - 1)); | |
991d9fa0 JT |
358 | } |
359 | ||
2dd9c257 JT |
360 | static void remap_to_origin(struct thin_c *tc, struct bio *bio) |
361 | { | |
362 | bio->bi_bdev = tc->origin_dev->bdev; | |
363 | } | |
364 | ||
4afdd680 JT |
365 | static int bio_triggers_commit(struct thin_c *tc, struct bio *bio) |
366 | { | |
367 | return (bio->bi_rw & (REQ_FLUSH | REQ_FUA)) && | |
368 | dm_thin_changed_this_transaction(tc->td); | |
369 | } | |
370 | ||
2dd9c257 | 371 | static void issue(struct thin_c *tc, struct bio *bio) |
991d9fa0 JT |
372 | { |
373 | struct pool *pool = tc->pool; | |
374 | unsigned long flags; | |
375 | ||
e49e5829 JT |
376 | if (!bio_triggers_commit(tc, bio)) { |
377 | generic_make_request(bio); | |
378 | return; | |
379 | } | |
380 | ||
991d9fa0 | 381 | /* |
e49e5829 JT |
382 | * Complete bio with an error if earlier I/O caused changes to |
383 | * the metadata that can't be committed e.g, due to I/O errors | |
384 | * on the metadata device. | |
991d9fa0 | 385 | */ |
e49e5829 JT |
386 | if (dm_thin_aborted_changes(tc->td)) { |
387 | bio_io_error(bio); | |
388 | return; | |
389 | } | |
390 | ||
391 | /* | |
392 | * Batch together any bios that trigger commits and then issue a | |
393 | * single commit for them in process_deferred_bios(). | |
394 | */ | |
395 | spin_lock_irqsave(&pool->lock, flags); | |
396 | bio_list_add(&pool->deferred_flush_bios, bio); | |
397 | spin_unlock_irqrestore(&pool->lock, flags); | |
991d9fa0 JT |
398 | } |
399 | ||
2dd9c257 JT |
400 | static void remap_to_origin_and_issue(struct thin_c *tc, struct bio *bio) |
401 | { | |
402 | remap_to_origin(tc, bio); | |
403 | issue(tc, bio); | |
404 | } | |
405 | ||
406 | static void remap_and_issue(struct thin_c *tc, struct bio *bio, | |
407 | dm_block_t block) | |
408 | { | |
409 | remap(tc, bio, block); | |
410 | issue(tc, bio); | |
411 | } | |
412 | ||
991d9fa0 JT |
413 | /* |
414 | * wake_worker() is used when new work is queued and when pool_resume is | |
415 | * ready to continue deferred IO processing. | |
416 | */ | |
417 | static void wake_worker(struct pool *pool) | |
418 | { | |
419 | queue_work(pool->wq, &pool->worker); | |
420 | } | |
421 | ||
422 | /*----------------------------------------------------------------*/ | |
423 | ||
424 | /* | |
425 | * Bio endio functions. | |
426 | */ | |
a24c2569 | 427 | struct dm_thin_new_mapping { |
991d9fa0 JT |
428 | struct list_head list; |
429 | ||
eb2aa48d JT |
430 | unsigned quiesced:1; |
431 | unsigned prepared:1; | |
104655fd | 432 | unsigned pass_discard:1; |
991d9fa0 JT |
433 | |
434 | struct thin_c *tc; | |
435 | dm_block_t virt_block; | |
436 | dm_block_t data_block; | |
a24c2569 | 437 | struct dm_bio_prison_cell *cell, *cell2; |
991d9fa0 JT |
438 | int err; |
439 | ||
440 | /* | |
441 | * If the bio covers the whole area of a block then we can avoid | |
442 | * zeroing or copying. Instead this bio is hooked. The bio will | |
443 | * still be in the cell, so care has to be taken to avoid issuing | |
444 | * the bio twice. | |
445 | */ | |
446 | struct bio *bio; | |
447 | bio_end_io_t *saved_bi_end_io; | |
448 | }; | |
449 | ||
a24c2569 | 450 | static void __maybe_add_mapping(struct dm_thin_new_mapping *m) |
991d9fa0 JT |
451 | { |
452 | struct pool *pool = m->tc->pool; | |
453 | ||
eb2aa48d | 454 | if (m->quiesced && m->prepared) { |
991d9fa0 JT |
455 | list_add(&m->list, &pool->prepared_mappings); |
456 | wake_worker(pool); | |
457 | } | |
458 | } | |
459 | ||
460 | static void copy_complete(int read_err, unsigned long write_err, void *context) | |
461 | { | |
462 | unsigned long flags; | |
a24c2569 | 463 | struct dm_thin_new_mapping *m = context; |
991d9fa0 JT |
464 | struct pool *pool = m->tc->pool; |
465 | ||
466 | m->err = read_err || write_err ? -EIO : 0; | |
467 | ||
468 | spin_lock_irqsave(&pool->lock, flags); | |
469 | m->prepared = 1; | |
470 | __maybe_add_mapping(m); | |
471 | spin_unlock_irqrestore(&pool->lock, flags); | |
472 | } | |
473 | ||
474 | static void overwrite_endio(struct bio *bio, int err) | |
475 | { | |
476 | unsigned long flags; | |
a24c2569 MS |
477 | struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr; |
478 | struct dm_thin_new_mapping *m = h->overwrite_mapping; | |
991d9fa0 JT |
479 | struct pool *pool = m->tc->pool; |
480 | ||
481 | m->err = err; | |
482 | ||
483 | spin_lock_irqsave(&pool->lock, flags); | |
484 | m->prepared = 1; | |
485 | __maybe_add_mapping(m); | |
486 | spin_unlock_irqrestore(&pool->lock, flags); | |
487 | } | |
488 | ||
991d9fa0 JT |
489 | /*----------------------------------------------------------------*/ |
490 | ||
491 | /* | |
492 | * Workqueue. | |
493 | */ | |
494 | ||
495 | /* | |
496 | * Prepared mapping jobs. | |
497 | */ | |
498 | ||
499 | /* | |
500 | * This sends the bios in the cell back to the deferred_bios list. | |
501 | */ | |
a24c2569 | 502 | static void cell_defer(struct thin_c *tc, struct dm_bio_prison_cell *cell, |
991d9fa0 JT |
503 | dm_block_t data_block) |
504 | { | |
505 | struct pool *pool = tc->pool; | |
506 | unsigned long flags; | |
507 | ||
508 | spin_lock_irqsave(&pool->lock, flags); | |
44feb387 | 509 | dm_cell_release(cell, &pool->deferred_bios); |
991d9fa0 JT |
510 | spin_unlock_irqrestore(&tc->pool->lock, flags); |
511 | ||
512 | wake_worker(pool); | |
513 | } | |
514 | ||
515 | /* | |
b7ca9c92 | 516 | * Same as cell_defer except it omits the original holder of the cell. |
991d9fa0 | 517 | */ |
a24c2569 | 518 | static void cell_defer_except(struct thin_c *tc, struct dm_bio_prison_cell *cell) |
991d9fa0 JT |
519 | { |
520 | struct bio_list bios; | |
991d9fa0 JT |
521 | struct pool *pool = tc->pool; |
522 | unsigned long flags; | |
523 | ||
524 | bio_list_init(&bios); | |
991d9fa0 JT |
525 | |
526 | spin_lock_irqsave(&pool->lock, flags); | |
44feb387 | 527 | dm_cell_release_no_holder(cell, &pool->deferred_bios); |
991d9fa0 JT |
528 | spin_unlock_irqrestore(&pool->lock, flags); |
529 | ||
530 | wake_worker(pool); | |
531 | } | |
532 | ||
e49e5829 JT |
533 | static void process_prepared_mapping_fail(struct dm_thin_new_mapping *m) |
534 | { | |
535 | if (m->bio) | |
536 | m->bio->bi_end_io = m->saved_bi_end_io; | |
44feb387 | 537 | dm_cell_error(m->cell); |
e49e5829 JT |
538 | list_del(&m->list); |
539 | mempool_free(m, m->tc->pool->mapping_pool); | |
540 | } | |
a24c2569 | 541 | static void process_prepared_mapping(struct dm_thin_new_mapping *m) |
991d9fa0 JT |
542 | { |
543 | struct thin_c *tc = m->tc; | |
544 | struct bio *bio; | |
545 | int r; | |
546 | ||
547 | bio = m->bio; | |
548 | if (bio) | |
549 | bio->bi_end_io = m->saved_bi_end_io; | |
550 | ||
551 | if (m->err) { | |
44feb387 | 552 | dm_cell_error(m->cell); |
905386f8 | 553 | goto out; |
991d9fa0 JT |
554 | } |
555 | ||
556 | /* | |
557 | * Commit the prepared block into the mapping btree. | |
558 | * Any I/O for this block arriving after this point will get | |
559 | * remapped to it directly. | |
560 | */ | |
561 | r = dm_thin_insert_block(tc->td, m->virt_block, m->data_block); | |
562 | if (r) { | |
563 | DMERR("dm_thin_insert_block() failed"); | |
44feb387 | 564 | dm_cell_error(m->cell); |
905386f8 | 565 | goto out; |
991d9fa0 JT |
566 | } |
567 | ||
568 | /* | |
569 | * Release any bios held while the block was being provisioned. | |
570 | * If we are processing a write bio that completely covers the block, | |
571 | * we already processed it so can ignore it now when processing | |
572 | * the bios in the cell. | |
573 | */ | |
574 | if (bio) { | |
6f94a4c4 | 575 | cell_defer_except(tc, m->cell); |
991d9fa0 JT |
576 | bio_endio(bio, 0); |
577 | } else | |
578 | cell_defer(tc, m->cell, m->data_block); | |
579 | ||
905386f8 | 580 | out: |
991d9fa0 JT |
581 | list_del(&m->list); |
582 | mempool_free(m, tc->pool->mapping_pool); | |
583 | } | |
584 | ||
e49e5829 | 585 | static void process_prepared_discard_fail(struct dm_thin_new_mapping *m) |
104655fd | 586 | { |
104655fd JT |
587 | struct thin_c *tc = m->tc; |
588 | ||
e49e5829 JT |
589 | bio_io_error(m->bio); |
590 | cell_defer_except(tc, m->cell); | |
591 | cell_defer_except(tc, m->cell2); | |
592 | mempool_free(m, tc->pool->mapping_pool); | |
593 | } | |
594 | ||
595 | static void process_prepared_discard_passdown(struct dm_thin_new_mapping *m) | |
596 | { | |
597 | struct thin_c *tc = m->tc; | |
104655fd | 598 | |
104655fd JT |
599 | if (m->pass_discard) |
600 | remap_and_issue(tc, m->bio, m->data_block); | |
601 | else | |
602 | bio_endio(m->bio, 0); | |
603 | ||
604 | cell_defer_except(tc, m->cell); | |
605 | cell_defer_except(tc, m->cell2); | |
606 | mempool_free(m, tc->pool->mapping_pool); | |
607 | } | |
608 | ||
e49e5829 JT |
609 | static void process_prepared_discard(struct dm_thin_new_mapping *m) |
610 | { | |
611 | int r; | |
612 | struct thin_c *tc = m->tc; | |
613 | ||
614 | r = dm_thin_remove_block(tc->td, m->virt_block); | |
615 | if (r) | |
616 | DMERR("dm_thin_remove_block() failed"); | |
617 | ||
618 | process_prepared_discard_passdown(m); | |
619 | } | |
620 | ||
104655fd | 621 | static void process_prepared(struct pool *pool, struct list_head *head, |
e49e5829 | 622 | process_mapping_fn *fn) |
991d9fa0 JT |
623 | { |
624 | unsigned long flags; | |
625 | struct list_head maps; | |
a24c2569 | 626 | struct dm_thin_new_mapping *m, *tmp; |
991d9fa0 JT |
627 | |
628 | INIT_LIST_HEAD(&maps); | |
629 | spin_lock_irqsave(&pool->lock, flags); | |
104655fd | 630 | list_splice_init(head, &maps); |
991d9fa0 JT |
631 | spin_unlock_irqrestore(&pool->lock, flags); |
632 | ||
633 | list_for_each_entry_safe(m, tmp, &maps, list) | |
e49e5829 | 634 | (*fn)(m); |
991d9fa0 JT |
635 | } |
636 | ||
637 | /* | |
638 | * Deferred bio jobs. | |
639 | */ | |
104655fd | 640 | static int io_overlaps_block(struct pool *pool, struct bio *bio) |
991d9fa0 | 641 | { |
f9a8e0cd | 642 | return bio->bi_size == (pool->sectors_per_block << SECTOR_SHIFT); |
104655fd JT |
643 | } |
644 | ||
645 | static int io_overwrites_block(struct pool *pool, struct bio *bio) | |
646 | { | |
647 | return (bio_data_dir(bio) == WRITE) && | |
648 | io_overlaps_block(pool, bio); | |
991d9fa0 JT |
649 | } |
650 | ||
651 | static void save_and_set_endio(struct bio *bio, bio_end_io_t **save, | |
652 | bio_end_io_t *fn) | |
653 | { | |
654 | *save = bio->bi_end_io; | |
655 | bio->bi_end_io = fn; | |
656 | } | |
657 | ||
658 | static int ensure_next_mapping(struct pool *pool) | |
659 | { | |
660 | if (pool->next_mapping) | |
661 | return 0; | |
662 | ||
663 | pool->next_mapping = mempool_alloc(pool->mapping_pool, GFP_ATOMIC); | |
664 | ||
665 | return pool->next_mapping ? 0 : -ENOMEM; | |
666 | } | |
667 | ||
a24c2569 | 668 | static struct dm_thin_new_mapping *get_next_mapping(struct pool *pool) |
991d9fa0 | 669 | { |
a24c2569 | 670 | struct dm_thin_new_mapping *r = pool->next_mapping; |
991d9fa0 JT |
671 | |
672 | BUG_ON(!pool->next_mapping); | |
673 | ||
674 | pool->next_mapping = NULL; | |
675 | ||
676 | return r; | |
677 | } | |
678 | ||
679 | static void schedule_copy(struct thin_c *tc, dm_block_t virt_block, | |
2dd9c257 JT |
680 | struct dm_dev *origin, dm_block_t data_origin, |
681 | dm_block_t data_dest, | |
a24c2569 | 682 | struct dm_bio_prison_cell *cell, struct bio *bio) |
991d9fa0 JT |
683 | { |
684 | int r; | |
685 | struct pool *pool = tc->pool; | |
a24c2569 | 686 | struct dm_thin_new_mapping *m = get_next_mapping(pool); |
991d9fa0 JT |
687 | |
688 | INIT_LIST_HEAD(&m->list); | |
eb2aa48d | 689 | m->quiesced = 0; |
991d9fa0 JT |
690 | m->prepared = 0; |
691 | m->tc = tc; | |
692 | m->virt_block = virt_block; | |
693 | m->data_block = data_dest; | |
694 | m->cell = cell; | |
695 | m->err = 0; | |
696 | m->bio = NULL; | |
697 | ||
44feb387 | 698 | if (!dm_deferred_set_add_work(pool->shared_read_ds, &m->list)) |
eb2aa48d | 699 | m->quiesced = 1; |
991d9fa0 JT |
700 | |
701 | /* | |
702 | * IO to pool_dev remaps to the pool target's data_dev. | |
703 | * | |
704 | * If the whole block of data is being overwritten, we can issue the | |
705 | * bio immediately. Otherwise we use kcopyd to clone the data first. | |
706 | */ | |
707 | if (io_overwrites_block(pool, bio)) { | |
a24c2569 MS |
708 | struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr; |
709 | ||
eb2aa48d | 710 | h->overwrite_mapping = m; |
991d9fa0 JT |
711 | m->bio = bio; |
712 | save_and_set_endio(bio, &m->saved_bi_end_io, overwrite_endio); | |
991d9fa0 JT |
713 | remap_and_issue(tc, bio, data_dest); |
714 | } else { | |
715 | struct dm_io_region from, to; | |
716 | ||
2dd9c257 | 717 | from.bdev = origin->bdev; |
991d9fa0 JT |
718 | from.sector = data_origin * pool->sectors_per_block; |
719 | from.count = pool->sectors_per_block; | |
720 | ||
721 | to.bdev = tc->pool_dev->bdev; | |
722 | to.sector = data_dest * pool->sectors_per_block; | |
723 | to.count = pool->sectors_per_block; | |
724 | ||
725 | r = dm_kcopyd_copy(pool->copier, &from, 1, &to, | |
726 | 0, copy_complete, m); | |
727 | if (r < 0) { | |
728 | mempool_free(m, pool->mapping_pool); | |
729 | DMERR("dm_kcopyd_copy() failed"); | |
44feb387 | 730 | dm_cell_error(cell); |
991d9fa0 JT |
731 | } |
732 | } | |
733 | } | |
734 | ||
2dd9c257 JT |
735 | static void schedule_internal_copy(struct thin_c *tc, dm_block_t virt_block, |
736 | dm_block_t data_origin, dm_block_t data_dest, | |
a24c2569 | 737 | struct dm_bio_prison_cell *cell, struct bio *bio) |
2dd9c257 JT |
738 | { |
739 | schedule_copy(tc, virt_block, tc->pool_dev, | |
740 | data_origin, data_dest, cell, bio); | |
741 | } | |
742 | ||
743 | static void schedule_external_copy(struct thin_c *tc, dm_block_t virt_block, | |
744 | dm_block_t data_dest, | |
a24c2569 | 745 | struct dm_bio_prison_cell *cell, struct bio *bio) |
2dd9c257 JT |
746 | { |
747 | schedule_copy(tc, virt_block, tc->origin_dev, | |
748 | virt_block, data_dest, cell, bio); | |
749 | } | |
750 | ||
991d9fa0 | 751 | static void schedule_zero(struct thin_c *tc, dm_block_t virt_block, |
a24c2569 | 752 | dm_block_t data_block, struct dm_bio_prison_cell *cell, |
991d9fa0 JT |
753 | struct bio *bio) |
754 | { | |
755 | struct pool *pool = tc->pool; | |
a24c2569 | 756 | struct dm_thin_new_mapping *m = get_next_mapping(pool); |
991d9fa0 JT |
757 | |
758 | INIT_LIST_HEAD(&m->list); | |
eb2aa48d | 759 | m->quiesced = 1; |
991d9fa0 JT |
760 | m->prepared = 0; |
761 | m->tc = tc; | |
762 | m->virt_block = virt_block; | |
763 | m->data_block = data_block; | |
764 | m->cell = cell; | |
765 | m->err = 0; | |
766 | m->bio = NULL; | |
767 | ||
768 | /* | |
769 | * If the whole block of data is being overwritten or we are not | |
770 | * zeroing pre-existing data, we can issue the bio immediately. | |
771 | * Otherwise we use kcopyd to zero the data first. | |
772 | */ | |
67e2e2b2 | 773 | if (!pool->pf.zero_new_blocks) |
991d9fa0 JT |
774 | process_prepared_mapping(m); |
775 | ||
776 | else if (io_overwrites_block(pool, bio)) { | |
a24c2569 MS |
777 | struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr; |
778 | ||
eb2aa48d | 779 | h->overwrite_mapping = m; |
991d9fa0 JT |
780 | m->bio = bio; |
781 | save_and_set_endio(bio, &m->saved_bi_end_io, overwrite_endio); | |
991d9fa0 | 782 | remap_and_issue(tc, bio, data_block); |
991d9fa0 JT |
783 | } else { |
784 | int r; | |
785 | struct dm_io_region to; | |
786 | ||
787 | to.bdev = tc->pool_dev->bdev; | |
788 | to.sector = data_block * pool->sectors_per_block; | |
789 | to.count = pool->sectors_per_block; | |
790 | ||
791 | r = dm_kcopyd_zero(pool->copier, 1, &to, 0, copy_complete, m); | |
792 | if (r < 0) { | |
793 | mempool_free(m, pool->mapping_pool); | |
794 | DMERR("dm_kcopyd_zero() failed"); | |
44feb387 | 795 | dm_cell_error(cell); |
991d9fa0 JT |
796 | } |
797 | } | |
798 | } | |
799 | ||
e49e5829 JT |
800 | static int commit(struct pool *pool) |
801 | { | |
802 | int r; | |
803 | ||
804 | r = dm_pool_commit_metadata(pool->pmd); | |
805 | if (r) | |
806 | DMERR("commit failed, error = %d", r); | |
807 | ||
808 | return r; | |
809 | } | |
810 | ||
811 | /* | |
812 | * A non-zero return indicates read_only or fail_io mode. | |
813 | * Many callers don't care about the return value. | |
814 | */ | |
815 | static int commit_or_fallback(struct pool *pool) | |
816 | { | |
817 | int r; | |
818 | ||
819 | if (get_pool_mode(pool) != PM_WRITE) | |
820 | return -EINVAL; | |
821 | ||
822 | r = commit(pool); | |
823 | if (r) | |
824 | set_pool_mode(pool, PM_READ_ONLY); | |
825 | ||
826 | return r; | |
827 | } | |
828 | ||
991d9fa0 JT |
829 | static int alloc_data_block(struct thin_c *tc, dm_block_t *result) |
830 | { | |
831 | int r; | |
832 | dm_block_t free_blocks; | |
833 | unsigned long flags; | |
834 | struct pool *pool = tc->pool; | |
835 | ||
836 | r = dm_pool_get_free_block_count(pool->pmd, &free_blocks); | |
837 | if (r) | |
838 | return r; | |
839 | ||
840 | if (free_blocks <= pool->low_water_blocks && !pool->low_water_triggered) { | |
841 | DMWARN("%s: reached low water mark, sending event.", | |
842 | dm_device_name(pool->pool_md)); | |
843 | spin_lock_irqsave(&pool->lock, flags); | |
844 | pool->low_water_triggered = 1; | |
845 | spin_unlock_irqrestore(&pool->lock, flags); | |
846 | dm_table_event(pool->ti->table); | |
847 | } | |
848 | ||
849 | if (!free_blocks) { | |
850 | if (pool->no_free_space) | |
851 | return -ENOSPC; | |
852 | else { | |
853 | /* | |
854 | * Try to commit to see if that will free up some | |
855 | * more space. | |
856 | */ | |
e49e5829 | 857 | (void) commit_or_fallback(pool); |
991d9fa0 JT |
858 | |
859 | r = dm_pool_get_free_block_count(pool->pmd, &free_blocks); | |
860 | if (r) | |
861 | return r; | |
862 | ||
863 | /* | |
864 | * If we still have no space we set a flag to avoid | |
865 | * doing all this checking and return -ENOSPC. | |
866 | */ | |
867 | if (!free_blocks) { | |
868 | DMWARN("%s: no free space available.", | |
869 | dm_device_name(pool->pool_md)); | |
870 | spin_lock_irqsave(&pool->lock, flags); | |
871 | pool->no_free_space = 1; | |
872 | spin_unlock_irqrestore(&pool->lock, flags); | |
873 | return -ENOSPC; | |
874 | } | |
875 | } | |
876 | } | |
877 | ||
878 | r = dm_pool_alloc_data_block(pool->pmd, result); | |
879 | if (r) | |
880 | return r; | |
881 | ||
882 | return 0; | |
883 | } | |
884 | ||
885 | /* | |
886 | * If we have run out of space, queue bios until the device is | |
887 | * resumed, presumably after having been reloaded with more space. | |
888 | */ | |
889 | static void retry_on_resume(struct bio *bio) | |
890 | { | |
a24c2569 | 891 | struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr; |
eb2aa48d | 892 | struct thin_c *tc = h->tc; |
991d9fa0 JT |
893 | struct pool *pool = tc->pool; |
894 | unsigned long flags; | |
895 | ||
896 | spin_lock_irqsave(&pool->lock, flags); | |
897 | bio_list_add(&pool->retry_on_resume_list, bio); | |
898 | spin_unlock_irqrestore(&pool->lock, flags); | |
899 | } | |
900 | ||
a24c2569 | 901 | static void no_space(struct dm_bio_prison_cell *cell) |
991d9fa0 JT |
902 | { |
903 | struct bio *bio; | |
904 | struct bio_list bios; | |
905 | ||
906 | bio_list_init(&bios); | |
44feb387 | 907 | dm_cell_release(cell, &bios); |
991d9fa0 JT |
908 | |
909 | while ((bio = bio_list_pop(&bios))) | |
910 | retry_on_resume(bio); | |
911 | } | |
912 | ||
104655fd JT |
913 | static void process_discard(struct thin_c *tc, struct bio *bio) |
914 | { | |
915 | int r; | |
c3a0ce2e | 916 | unsigned long flags; |
104655fd | 917 | struct pool *pool = tc->pool; |
a24c2569 | 918 | struct dm_bio_prison_cell *cell, *cell2; |
44feb387 | 919 | struct dm_cell_key key, key2; |
104655fd JT |
920 | dm_block_t block = get_bio_block(tc, bio); |
921 | struct dm_thin_lookup_result lookup_result; | |
a24c2569 | 922 | struct dm_thin_new_mapping *m; |
104655fd JT |
923 | |
924 | build_virtual_key(tc->td, block, &key); | |
44feb387 | 925 | if (dm_bio_detain(tc->pool->prison, &key, bio, &cell)) |
104655fd JT |
926 | return; |
927 | ||
928 | r = dm_thin_find_block(tc->td, block, 1, &lookup_result); | |
929 | switch (r) { | |
930 | case 0: | |
931 | /* | |
932 | * Check nobody is fiddling with this pool block. This can | |
933 | * happen if someone's in the process of breaking sharing | |
934 | * on this block. | |
935 | */ | |
936 | build_data_key(tc->td, lookup_result.block, &key2); | |
44feb387 | 937 | if (dm_bio_detain(tc->pool->prison, &key2, bio, &cell2)) { |
b7ca9c92 | 938 | cell_defer_except(tc, cell); |
104655fd JT |
939 | break; |
940 | } | |
941 | ||
942 | if (io_overlaps_block(pool, bio)) { | |
943 | /* | |
944 | * IO may still be going to the destination block. We must | |
945 | * quiesce before we can do the removal. | |
946 | */ | |
947 | m = get_next_mapping(pool); | |
948 | m->tc = tc; | |
17b7d63f | 949 | m->pass_discard = (!lookup_result.shared) && pool->pf.discard_passdown; |
104655fd JT |
950 | m->virt_block = block; |
951 | m->data_block = lookup_result.block; | |
952 | m->cell = cell; | |
953 | m->cell2 = cell2; | |
954 | m->err = 0; | |
955 | m->bio = bio; | |
956 | ||
44feb387 | 957 | if (!dm_deferred_set_add_work(pool->all_io_ds, &m->list)) { |
c3a0ce2e | 958 | spin_lock_irqsave(&pool->lock, flags); |
104655fd | 959 | list_add(&m->list, &pool->prepared_discards); |
c3a0ce2e | 960 | spin_unlock_irqrestore(&pool->lock, flags); |
104655fd JT |
961 | wake_worker(pool); |
962 | } | |
963 | } else { | |
964 | /* | |
49296309 MP |
965 | * The DM core makes sure that the discard doesn't span |
966 | * a block boundary. So we submit the discard of a | |
967 | * partial block appropriately. | |
104655fd | 968 | */ |
b7ca9c92 JT |
969 | cell_defer_except(tc, cell); |
970 | cell_defer_except(tc, cell2); | |
650d2a06 MP |
971 | if ((!lookup_result.shared) && pool->pf.discard_passdown) |
972 | remap_and_issue(tc, bio, lookup_result.block); | |
973 | else | |
974 | bio_endio(bio, 0); | |
104655fd JT |
975 | } |
976 | break; | |
977 | ||
978 | case -ENODATA: | |
979 | /* | |
980 | * It isn't provisioned, just forget it. | |
981 | */ | |
b7ca9c92 | 982 | cell_defer_except(tc, cell); |
104655fd JT |
983 | bio_endio(bio, 0); |
984 | break; | |
985 | ||
986 | default: | |
987 | DMERR("discard: find block unexpectedly returned %d", r); | |
b7ca9c92 | 988 | cell_defer_except(tc, cell); |
104655fd JT |
989 | bio_io_error(bio); |
990 | break; | |
991 | } | |
992 | } | |
993 | ||
991d9fa0 | 994 | static void break_sharing(struct thin_c *tc, struct bio *bio, dm_block_t block, |
44feb387 | 995 | struct dm_cell_key *key, |
991d9fa0 | 996 | struct dm_thin_lookup_result *lookup_result, |
a24c2569 | 997 | struct dm_bio_prison_cell *cell) |
991d9fa0 JT |
998 | { |
999 | int r; | |
1000 | dm_block_t data_block; | |
1001 | ||
1002 | r = alloc_data_block(tc, &data_block); | |
1003 | switch (r) { | |
1004 | case 0: | |
2dd9c257 JT |
1005 | schedule_internal_copy(tc, block, lookup_result->block, |
1006 | data_block, cell, bio); | |
991d9fa0 JT |
1007 | break; |
1008 | ||
1009 | case -ENOSPC: | |
1010 | no_space(cell); | |
1011 | break; | |
1012 | ||
1013 | default: | |
1014 | DMERR("%s: alloc_data_block() failed, error = %d", __func__, r); | |
44feb387 | 1015 | dm_cell_error(cell); |
991d9fa0 JT |
1016 | break; |
1017 | } | |
1018 | } | |
1019 | ||
1020 | static void process_shared_bio(struct thin_c *tc, struct bio *bio, | |
1021 | dm_block_t block, | |
1022 | struct dm_thin_lookup_result *lookup_result) | |
1023 | { | |
a24c2569 | 1024 | struct dm_bio_prison_cell *cell; |
991d9fa0 | 1025 | struct pool *pool = tc->pool; |
44feb387 | 1026 | struct dm_cell_key key; |
991d9fa0 JT |
1027 | |
1028 | /* | |
1029 | * If cell is already occupied, then sharing is already in the process | |
1030 | * of being broken so we have nothing further to do here. | |
1031 | */ | |
1032 | build_data_key(tc->td, lookup_result->block, &key); | |
44feb387 | 1033 | if (dm_bio_detain(pool->prison, &key, bio, &cell)) |
991d9fa0 JT |
1034 | return; |
1035 | ||
60049701 | 1036 | if (bio_data_dir(bio) == WRITE && bio->bi_size) |
991d9fa0 JT |
1037 | break_sharing(tc, bio, block, &key, lookup_result, cell); |
1038 | else { | |
a24c2569 | 1039 | struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr; |
991d9fa0 | 1040 | |
44feb387 | 1041 | h->shared_read_entry = dm_deferred_entry_inc(pool->shared_read_ds); |
991d9fa0 | 1042 | |
b7ca9c92 | 1043 | cell_defer_except(tc, cell); |
991d9fa0 JT |
1044 | remap_and_issue(tc, bio, lookup_result->block); |
1045 | } | |
1046 | } | |
1047 | ||
1048 | static void provision_block(struct thin_c *tc, struct bio *bio, dm_block_t block, | |
a24c2569 | 1049 | struct dm_bio_prison_cell *cell) |
991d9fa0 JT |
1050 | { |
1051 | int r; | |
1052 | dm_block_t data_block; | |
1053 | ||
1054 | /* | |
1055 | * Remap empty bios (flushes) immediately, without provisioning. | |
1056 | */ | |
1057 | if (!bio->bi_size) { | |
b7ca9c92 | 1058 | cell_defer_except(tc, cell); |
991d9fa0 JT |
1059 | remap_and_issue(tc, bio, 0); |
1060 | return; | |
1061 | } | |
1062 | ||
1063 | /* | |
1064 | * Fill read bios with zeroes and complete them immediately. | |
1065 | */ | |
1066 | if (bio_data_dir(bio) == READ) { | |
1067 | zero_fill_bio(bio); | |
b7ca9c92 | 1068 | cell_defer_except(tc, cell); |
991d9fa0 JT |
1069 | bio_endio(bio, 0); |
1070 | return; | |
1071 | } | |
1072 | ||
1073 | r = alloc_data_block(tc, &data_block); | |
1074 | switch (r) { | |
1075 | case 0: | |
2dd9c257 JT |
1076 | if (tc->origin_dev) |
1077 | schedule_external_copy(tc, block, data_block, cell, bio); | |
1078 | else | |
1079 | schedule_zero(tc, block, data_block, cell, bio); | |
991d9fa0 JT |
1080 | break; |
1081 | ||
1082 | case -ENOSPC: | |
1083 | no_space(cell); | |
1084 | break; | |
1085 | ||
1086 | default: | |
1087 | DMERR("%s: alloc_data_block() failed, error = %d", __func__, r); | |
e49e5829 | 1088 | set_pool_mode(tc->pool, PM_READ_ONLY); |
44feb387 | 1089 | dm_cell_error(cell); |
991d9fa0 JT |
1090 | break; |
1091 | } | |
1092 | } | |
1093 | ||
1094 | static void process_bio(struct thin_c *tc, struct bio *bio) | |
1095 | { | |
1096 | int r; | |
1097 | dm_block_t block = get_bio_block(tc, bio); | |
a24c2569 | 1098 | struct dm_bio_prison_cell *cell; |
44feb387 | 1099 | struct dm_cell_key key; |
991d9fa0 JT |
1100 | struct dm_thin_lookup_result lookup_result; |
1101 | ||
1102 | /* | |
1103 | * If cell is already occupied, then the block is already | |
1104 | * being provisioned so we have nothing further to do here. | |
1105 | */ | |
1106 | build_virtual_key(tc->td, block, &key); | |
44feb387 | 1107 | if (dm_bio_detain(tc->pool->prison, &key, bio, &cell)) |
991d9fa0 JT |
1108 | return; |
1109 | ||
1110 | r = dm_thin_find_block(tc->td, block, 1, &lookup_result); | |
1111 | switch (r) { | |
1112 | case 0: | |
1113 | /* | |
1114 | * We can release this cell now. This thread is the only | |
1115 | * one that puts bios into a cell, and we know there were | |
1116 | * no preceding bios. | |
1117 | */ | |
1118 | /* | |
1119 | * TODO: this will probably have to change when discard goes | |
1120 | * back in. | |
1121 | */ | |
b7ca9c92 | 1122 | cell_defer_except(tc, cell); |
991d9fa0 JT |
1123 | |
1124 | if (lookup_result.shared) | |
1125 | process_shared_bio(tc, bio, block, &lookup_result); | |
1126 | else | |
1127 | remap_and_issue(tc, bio, lookup_result.block); | |
1128 | break; | |
1129 | ||
1130 | case -ENODATA: | |
2dd9c257 | 1131 | if (bio_data_dir(bio) == READ && tc->origin_dev) { |
b7ca9c92 | 1132 | cell_defer_except(tc, cell); |
2dd9c257 JT |
1133 | remap_to_origin_and_issue(tc, bio); |
1134 | } else | |
1135 | provision_block(tc, bio, block, cell); | |
991d9fa0 JT |
1136 | break; |
1137 | ||
1138 | default: | |
1139 | DMERR("dm_thin_find_block() failed, error = %d", r); | |
b7ca9c92 | 1140 | cell_defer_except(tc, cell); |
991d9fa0 JT |
1141 | bio_io_error(bio); |
1142 | break; | |
1143 | } | |
1144 | } | |
1145 | ||
e49e5829 JT |
1146 | static void process_bio_read_only(struct thin_c *tc, struct bio *bio) |
1147 | { | |
1148 | int r; | |
1149 | int rw = bio_data_dir(bio); | |
1150 | dm_block_t block = get_bio_block(tc, bio); | |
1151 | struct dm_thin_lookup_result lookup_result; | |
1152 | ||
1153 | r = dm_thin_find_block(tc->td, block, 1, &lookup_result); | |
1154 | switch (r) { | |
1155 | case 0: | |
1156 | if (lookup_result.shared && (rw == WRITE) && bio->bi_size) | |
1157 | bio_io_error(bio); | |
1158 | else | |
1159 | remap_and_issue(tc, bio, lookup_result.block); | |
1160 | break; | |
1161 | ||
1162 | case -ENODATA: | |
1163 | if (rw != READ) { | |
1164 | bio_io_error(bio); | |
1165 | break; | |
1166 | } | |
1167 | ||
1168 | if (tc->origin_dev) { | |
1169 | remap_to_origin_and_issue(tc, bio); | |
1170 | break; | |
1171 | } | |
1172 | ||
1173 | zero_fill_bio(bio); | |
1174 | bio_endio(bio, 0); | |
1175 | break; | |
1176 | ||
1177 | default: | |
1178 | DMERR("dm_thin_find_block() failed, error = %d", r); | |
1179 | bio_io_error(bio); | |
1180 | break; | |
1181 | } | |
1182 | } | |
1183 | ||
1184 | static void process_bio_fail(struct thin_c *tc, struct bio *bio) | |
1185 | { | |
1186 | bio_io_error(bio); | |
1187 | } | |
1188 | ||
905e51b3 JT |
1189 | static int need_commit_due_to_time(struct pool *pool) |
1190 | { | |
1191 | return jiffies < pool->last_commit_jiffies || | |
1192 | jiffies > pool->last_commit_jiffies + COMMIT_PERIOD; | |
1193 | } | |
1194 | ||
991d9fa0 JT |
1195 | static void process_deferred_bios(struct pool *pool) |
1196 | { | |
1197 | unsigned long flags; | |
1198 | struct bio *bio; | |
1199 | struct bio_list bios; | |
991d9fa0 JT |
1200 | |
1201 | bio_list_init(&bios); | |
1202 | ||
1203 | spin_lock_irqsave(&pool->lock, flags); | |
1204 | bio_list_merge(&bios, &pool->deferred_bios); | |
1205 | bio_list_init(&pool->deferred_bios); | |
1206 | spin_unlock_irqrestore(&pool->lock, flags); | |
1207 | ||
1208 | while ((bio = bio_list_pop(&bios))) { | |
a24c2569 | 1209 | struct dm_thin_endio_hook *h = dm_get_mapinfo(bio)->ptr; |
eb2aa48d JT |
1210 | struct thin_c *tc = h->tc; |
1211 | ||
991d9fa0 JT |
1212 | /* |
1213 | * If we've got no free new_mapping structs, and processing | |
1214 | * this bio might require one, we pause until there are some | |
1215 | * prepared mappings to process. | |
1216 | */ | |
1217 | if (ensure_next_mapping(pool)) { | |
1218 | spin_lock_irqsave(&pool->lock, flags); | |
1219 | bio_list_merge(&pool->deferred_bios, &bios); | |
1220 | spin_unlock_irqrestore(&pool->lock, flags); | |
1221 | ||
1222 | break; | |
1223 | } | |
104655fd JT |
1224 | |
1225 | if (bio->bi_rw & REQ_DISCARD) | |
e49e5829 | 1226 | pool->process_discard(tc, bio); |
104655fd | 1227 | else |
e49e5829 | 1228 | pool->process_bio(tc, bio); |
991d9fa0 JT |
1229 | } |
1230 | ||
1231 | /* | |
1232 | * If there are any deferred flush bios, we must commit | |
1233 | * the metadata before issuing them. | |
1234 | */ | |
1235 | bio_list_init(&bios); | |
1236 | spin_lock_irqsave(&pool->lock, flags); | |
1237 | bio_list_merge(&bios, &pool->deferred_flush_bios); | |
1238 | bio_list_init(&pool->deferred_flush_bios); | |
1239 | spin_unlock_irqrestore(&pool->lock, flags); | |
1240 | ||
905e51b3 | 1241 | if (bio_list_empty(&bios) && !need_commit_due_to_time(pool)) |
991d9fa0 JT |
1242 | return; |
1243 | ||
e49e5829 | 1244 | if (commit_or_fallback(pool)) { |
991d9fa0 JT |
1245 | while ((bio = bio_list_pop(&bios))) |
1246 | bio_io_error(bio); | |
1247 | return; | |
1248 | } | |
905e51b3 | 1249 | pool->last_commit_jiffies = jiffies; |
991d9fa0 JT |
1250 | |
1251 | while ((bio = bio_list_pop(&bios))) | |
1252 | generic_make_request(bio); | |
1253 | } | |
1254 | ||
1255 | static void do_worker(struct work_struct *ws) | |
1256 | { | |
1257 | struct pool *pool = container_of(ws, struct pool, worker); | |
1258 | ||
e49e5829 JT |
1259 | process_prepared(pool, &pool->prepared_mappings, &pool->process_prepared_mapping); |
1260 | process_prepared(pool, &pool->prepared_discards, &pool->process_prepared_discard); | |
991d9fa0 JT |
1261 | process_deferred_bios(pool); |
1262 | } | |
1263 | ||
905e51b3 JT |
1264 | /* |
1265 | * We want to commit periodically so that not too much | |
1266 | * unwritten data builds up. | |
1267 | */ | |
1268 | static void do_waker(struct work_struct *ws) | |
1269 | { | |
1270 | struct pool *pool = container_of(to_delayed_work(ws), struct pool, waker); | |
1271 | wake_worker(pool); | |
1272 | queue_delayed_work(pool->wq, &pool->waker, COMMIT_PERIOD); | |
1273 | } | |
1274 | ||
991d9fa0 JT |
1275 | /*----------------------------------------------------------------*/ |
1276 | ||
e49e5829 JT |
1277 | static enum pool_mode get_pool_mode(struct pool *pool) |
1278 | { | |
1279 | return pool->pf.mode; | |
1280 | } | |
1281 | ||
1282 | static void set_pool_mode(struct pool *pool, enum pool_mode mode) | |
1283 | { | |
1284 | int r; | |
1285 | ||
1286 | pool->pf.mode = mode; | |
1287 | ||
1288 | switch (mode) { | |
1289 | case PM_FAIL: | |
1290 | DMERR("switching pool to failure mode"); | |
1291 | pool->process_bio = process_bio_fail; | |
1292 | pool->process_discard = process_bio_fail; | |
1293 | pool->process_prepared_mapping = process_prepared_mapping_fail; | |
1294 | pool->process_prepared_discard = process_prepared_discard_fail; | |
1295 | break; | |
1296 | ||
1297 | case PM_READ_ONLY: | |
1298 | DMERR("switching pool to read-only mode"); | |
1299 | r = dm_pool_abort_metadata(pool->pmd); | |
1300 | if (r) { | |
1301 | DMERR("aborting transaction failed"); | |
1302 | set_pool_mode(pool, PM_FAIL); | |
1303 | } else { | |
1304 | dm_pool_metadata_read_only(pool->pmd); | |
1305 | pool->process_bio = process_bio_read_only; | |
1306 | pool->process_discard = process_discard; | |
1307 | pool->process_prepared_mapping = process_prepared_mapping_fail; | |
1308 | pool->process_prepared_discard = process_prepared_discard_passdown; | |
1309 | } | |
1310 | break; | |
1311 | ||
1312 | case PM_WRITE: | |
1313 | pool->process_bio = process_bio; | |
1314 | pool->process_discard = process_discard; | |
1315 | pool->process_prepared_mapping = process_prepared_mapping; | |
1316 | pool->process_prepared_discard = process_prepared_discard; | |
1317 | break; | |
1318 | } | |
1319 | } | |
1320 | ||
1321 | /*----------------------------------------------------------------*/ | |
1322 | ||
991d9fa0 JT |
1323 | /* |
1324 | * Mapping functions. | |
1325 | */ | |
1326 | ||
1327 | /* | |
1328 | * Called only while mapping a thin bio to hand it over to the workqueue. | |
1329 | */ | |
1330 | static void thin_defer_bio(struct thin_c *tc, struct bio *bio) | |
1331 | { | |
1332 | unsigned long flags; | |
1333 | struct pool *pool = tc->pool; | |
1334 | ||
1335 | spin_lock_irqsave(&pool->lock, flags); | |
1336 | bio_list_add(&pool->deferred_bios, bio); | |
1337 | spin_unlock_irqrestore(&pool->lock, flags); | |
1338 | ||
1339 | wake_worker(pool); | |
1340 | } | |
1341 | ||
a24c2569 | 1342 | static struct dm_thin_endio_hook *thin_hook_bio(struct thin_c *tc, struct bio *bio) |
eb2aa48d JT |
1343 | { |
1344 | struct pool *pool = tc->pool; | |
a24c2569 | 1345 | struct dm_thin_endio_hook *h = mempool_alloc(pool->endio_hook_pool, GFP_NOIO); |
eb2aa48d JT |
1346 | |
1347 | h->tc = tc; | |
1348 | h->shared_read_entry = NULL; | |
44feb387 | 1349 | h->all_io_entry = bio->bi_rw & REQ_DISCARD ? NULL : dm_deferred_entry_inc(pool->all_io_ds); |
eb2aa48d JT |
1350 | h->overwrite_mapping = NULL; |
1351 | ||
1352 | return h; | |
1353 | } | |
1354 | ||
991d9fa0 JT |
1355 | /* |
1356 | * Non-blocking function called from the thin target's map function. | |
1357 | */ | |
1358 | static int thin_bio_map(struct dm_target *ti, struct bio *bio, | |
1359 | union map_info *map_context) | |
1360 | { | |
1361 | int r; | |
1362 | struct thin_c *tc = ti->private; | |
1363 | dm_block_t block = get_bio_block(tc, bio); | |
1364 | struct dm_thin_device *td = tc->td; | |
1365 | struct dm_thin_lookup_result result; | |
1366 | ||
eb2aa48d | 1367 | map_context->ptr = thin_hook_bio(tc, bio); |
e49e5829 JT |
1368 | |
1369 | if (get_pool_mode(tc->pool) == PM_FAIL) { | |
1370 | bio_io_error(bio); | |
1371 | return DM_MAPIO_SUBMITTED; | |
1372 | } | |
1373 | ||
104655fd | 1374 | if (bio->bi_rw & (REQ_DISCARD | REQ_FLUSH | REQ_FUA)) { |
991d9fa0 JT |
1375 | thin_defer_bio(tc, bio); |
1376 | return DM_MAPIO_SUBMITTED; | |
1377 | } | |
1378 | ||
1379 | r = dm_thin_find_block(td, block, 0, &result); | |
1380 | ||
1381 | /* | |
1382 | * Note that we defer readahead too. | |
1383 | */ | |
1384 | switch (r) { | |
1385 | case 0: | |
1386 | if (unlikely(result.shared)) { | |
1387 | /* | |
1388 | * We have a race condition here between the | |
1389 | * result.shared value returned by the lookup and | |
1390 | * snapshot creation, which may cause new | |
1391 | * sharing. | |
1392 | * | |
1393 | * To avoid this always quiesce the origin before | |
1394 | * taking the snap. You want to do this anyway to | |
1395 | * ensure a consistent application view | |
1396 | * (i.e. lockfs). | |
1397 | * | |
1398 | * More distant ancestors are irrelevant. The | |
1399 | * shared flag will be set in their case. | |
1400 | */ | |
1401 | thin_defer_bio(tc, bio); | |
1402 | r = DM_MAPIO_SUBMITTED; | |
1403 | } else { | |
1404 | remap(tc, bio, result.block); | |
1405 | r = DM_MAPIO_REMAPPED; | |
1406 | } | |
1407 | break; | |
1408 | ||
1409 | case -ENODATA: | |
e49e5829 JT |
1410 | if (get_pool_mode(tc->pool) == PM_READ_ONLY) { |
1411 | /* | |
1412 | * This block isn't provisioned, and we have no way | |
1413 | * of doing so. Just error it. | |
1414 | */ | |
1415 | bio_io_error(bio); | |
1416 | r = DM_MAPIO_SUBMITTED; | |
1417 | break; | |
1418 | } | |
1419 | /* fall through */ | |
1420 | ||
1421 | case -EWOULDBLOCK: | |
991d9fa0 JT |
1422 | /* |
1423 | * In future, the failed dm_thin_find_block above could | |
1424 | * provide the hint to load the metadata into cache. | |
1425 | */ | |
991d9fa0 JT |
1426 | thin_defer_bio(tc, bio); |
1427 | r = DM_MAPIO_SUBMITTED; | |
1428 | break; | |
e49e5829 JT |
1429 | |
1430 | default: | |
1431 | /* | |
1432 | * Must always call bio_io_error on failure. | |
1433 | * dm_thin_find_block can fail with -EINVAL if the | |
1434 | * pool is switched to fail-io mode. | |
1435 | */ | |
1436 | bio_io_error(bio); | |
1437 | r = DM_MAPIO_SUBMITTED; | |
1438 | break; | |
991d9fa0 JT |
1439 | } |
1440 | ||
1441 | return r; | |
1442 | } | |
1443 | ||
1444 | static int pool_is_congested(struct dm_target_callbacks *cb, int bdi_bits) | |
1445 | { | |
1446 | int r; | |
1447 | unsigned long flags; | |
1448 | struct pool_c *pt = container_of(cb, struct pool_c, callbacks); | |
1449 | ||
1450 | spin_lock_irqsave(&pt->pool->lock, flags); | |
1451 | r = !bio_list_empty(&pt->pool->retry_on_resume_list); | |
1452 | spin_unlock_irqrestore(&pt->pool->lock, flags); | |
1453 | ||
1454 | if (!r) { | |
1455 | struct request_queue *q = bdev_get_queue(pt->data_dev->bdev); | |
1456 | r = bdi_congested(&q->backing_dev_info, bdi_bits); | |
1457 | } | |
1458 | ||
1459 | return r; | |
1460 | } | |
1461 | ||
1462 | static void __requeue_bios(struct pool *pool) | |
1463 | { | |
1464 | bio_list_merge(&pool->deferred_bios, &pool->retry_on_resume_list); | |
1465 | bio_list_init(&pool->retry_on_resume_list); | |
1466 | } | |
1467 | ||
1468 | /*---------------------------------------------------------------- | |
1469 | * Binding of control targets to a pool object | |
1470 | *--------------------------------------------------------------*/ | |
9bc142dd MS |
1471 | static bool data_dev_supports_discard(struct pool_c *pt) |
1472 | { | |
1473 | struct request_queue *q = bdev_get_queue(pt->data_dev->bdev); | |
1474 | ||
1475 | return q && blk_queue_discard(q); | |
1476 | } | |
1477 | ||
1478 | /* | |
1479 | * If discard_passdown was enabled verify that the data device | |
0424caa1 | 1480 | * supports discards. Disable discard_passdown if not. |
9bc142dd | 1481 | */ |
0424caa1 | 1482 | static void disable_passdown_if_not_supported(struct pool_c *pt) |
9bc142dd | 1483 | { |
0424caa1 MS |
1484 | struct pool *pool = pt->pool; |
1485 | struct block_device *data_bdev = pt->data_dev->bdev; | |
1486 | struct queue_limits *data_limits = &bdev_get_queue(data_bdev)->limits; | |
1487 | sector_t block_size = pool->sectors_per_block << SECTOR_SHIFT; | |
1488 | const char *reason = NULL; | |
9bc142dd MS |
1489 | char buf[BDEVNAME_SIZE]; |
1490 | ||
0424caa1 | 1491 | if (!pt->adjusted_pf.discard_passdown) |
9bc142dd MS |
1492 | return; |
1493 | ||
0424caa1 MS |
1494 | if (!data_dev_supports_discard(pt)) |
1495 | reason = "discard unsupported"; | |
1496 | ||
1497 | else if (data_limits->max_discard_sectors < pool->sectors_per_block) | |
1498 | reason = "max discard sectors smaller than a block"; | |
9bc142dd | 1499 | |
0424caa1 MS |
1500 | else if (data_limits->discard_granularity > block_size) |
1501 | reason = "discard granularity larger than a block"; | |
1502 | ||
1503 | else if (block_size & (data_limits->discard_granularity - 1)) | |
1504 | reason = "discard granularity not a factor of block size"; | |
1505 | ||
1506 | if (reason) { | |
1507 | DMWARN("Data device (%s) %s: Disabling discard passdown.", bdevname(data_bdev, buf), reason); | |
1508 | pt->adjusted_pf.discard_passdown = false; | |
1509 | } | |
9bc142dd MS |
1510 | } |
1511 | ||
991d9fa0 JT |
1512 | static int bind_control_target(struct pool *pool, struct dm_target *ti) |
1513 | { | |
1514 | struct pool_c *pt = ti->private; | |
1515 | ||
e49e5829 JT |
1516 | /* |
1517 | * We want to make sure that degraded pools are never upgraded. | |
1518 | */ | |
1519 | enum pool_mode old_mode = pool->pf.mode; | |
0424caa1 | 1520 | enum pool_mode new_mode = pt->adjusted_pf.mode; |
e49e5829 JT |
1521 | |
1522 | if (old_mode > new_mode) | |
1523 | new_mode = old_mode; | |
1524 | ||
991d9fa0 JT |
1525 | pool->ti = ti; |
1526 | pool->low_water_blocks = pt->low_water_blocks; | |
0424caa1 | 1527 | pool->pf = pt->adjusted_pf; |
991d9fa0 | 1528 | |
9bc142dd | 1529 | set_pool_mode(pool, new_mode); |
f402693d | 1530 | |
991d9fa0 JT |
1531 | return 0; |
1532 | } | |
1533 | ||
1534 | static void unbind_control_target(struct pool *pool, struct dm_target *ti) | |
1535 | { | |
1536 | if (pool->ti == ti) | |
1537 | pool->ti = NULL; | |
1538 | } | |
1539 | ||
1540 | /*---------------------------------------------------------------- | |
1541 | * Pool creation | |
1542 | *--------------------------------------------------------------*/ | |
67e2e2b2 JT |
1543 | /* Initialize pool features. */ |
1544 | static void pool_features_init(struct pool_features *pf) | |
1545 | { | |
e49e5829 | 1546 | pf->mode = PM_WRITE; |
9bc142dd MS |
1547 | pf->zero_new_blocks = true; |
1548 | pf->discard_enabled = true; | |
1549 | pf->discard_passdown = true; | |
67e2e2b2 JT |
1550 | } |
1551 | ||
991d9fa0 JT |
1552 | static void __pool_destroy(struct pool *pool) |
1553 | { | |
1554 | __pool_table_remove(pool); | |
1555 | ||
1556 | if (dm_pool_metadata_close(pool->pmd) < 0) | |
1557 | DMWARN("%s: dm_pool_metadata_close() failed.", __func__); | |
1558 | ||
44feb387 | 1559 | dm_bio_prison_destroy(pool->prison); |
991d9fa0 JT |
1560 | dm_kcopyd_client_destroy(pool->copier); |
1561 | ||
1562 | if (pool->wq) | |
1563 | destroy_workqueue(pool->wq); | |
1564 | ||
1565 | if (pool->next_mapping) | |
1566 | mempool_free(pool->next_mapping, pool->mapping_pool); | |
1567 | mempool_destroy(pool->mapping_pool); | |
1568 | mempool_destroy(pool->endio_hook_pool); | |
44feb387 MS |
1569 | dm_deferred_set_destroy(pool->shared_read_ds); |
1570 | dm_deferred_set_destroy(pool->all_io_ds); | |
991d9fa0 JT |
1571 | kfree(pool); |
1572 | } | |
1573 | ||
a24c2569 MS |
1574 | static struct kmem_cache *_new_mapping_cache; |
1575 | static struct kmem_cache *_endio_hook_cache; | |
1576 | ||
991d9fa0 JT |
1577 | static struct pool *pool_create(struct mapped_device *pool_md, |
1578 | struct block_device *metadata_dev, | |
e49e5829 JT |
1579 | unsigned long block_size, |
1580 | int read_only, char **error) | |
991d9fa0 JT |
1581 | { |
1582 | int r; | |
1583 | void *err_p; | |
1584 | struct pool *pool; | |
1585 | struct dm_pool_metadata *pmd; | |
e49e5829 | 1586 | bool format_device = read_only ? false : true; |
991d9fa0 | 1587 | |
e49e5829 | 1588 | pmd = dm_pool_metadata_open(metadata_dev, block_size, format_device); |
991d9fa0 JT |
1589 | if (IS_ERR(pmd)) { |
1590 | *error = "Error creating metadata object"; | |
1591 | return (struct pool *)pmd; | |
1592 | } | |
1593 | ||
1594 | pool = kmalloc(sizeof(*pool), GFP_KERNEL); | |
1595 | if (!pool) { | |
1596 | *error = "Error allocating memory for pool"; | |
1597 | err_p = ERR_PTR(-ENOMEM); | |
1598 | goto bad_pool; | |
1599 | } | |
1600 | ||
1601 | pool->pmd = pmd; | |
1602 | pool->sectors_per_block = block_size; | |
f9a8e0cd MP |
1603 | if (block_size & (block_size - 1)) |
1604 | pool->sectors_per_block_shift = -1; | |
1605 | else | |
1606 | pool->sectors_per_block_shift = __ffs(block_size); | |
991d9fa0 | 1607 | pool->low_water_blocks = 0; |
67e2e2b2 | 1608 | pool_features_init(&pool->pf); |
44feb387 | 1609 | pool->prison = dm_bio_prison_create(PRISON_CELLS); |
991d9fa0 JT |
1610 | if (!pool->prison) { |
1611 | *error = "Error creating pool's bio prison"; | |
1612 | err_p = ERR_PTR(-ENOMEM); | |
1613 | goto bad_prison; | |
1614 | } | |
1615 | ||
1616 | pool->copier = dm_kcopyd_client_create(); | |
1617 | if (IS_ERR(pool->copier)) { | |
1618 | r = PTR_ERR(pool->copier); | |
1619 | *error = "Error creating pool's kcopyd client"; | |
1620 | err_p = ERR_PTR(r); | |
1621 | goto bad_kcopyd_client; | |
1622 | } | |
1623 | ||
1624 | /* | |
1625 | * Create singlethreaded workqueue that will service all devices | |
1626 | * that use this metadata. | |
1627 | */ | |
1628 | pool->wq = alloc_ordered_workqueue("dm-" DM_MSG_PREFIX, WQ_MEM_RECLAIM); | |
1629 | if (!pool->wq) { | |
1630 | *error = "Error creating pool's workqueue"; | |
1631 | err_p = ERR_PTR(-ENOMEM); | |
1632 | goto bad_wq; | |
1633 | } | |
1634 | ||
1635 | INIT_WORK(&pool->worker, do_worker); | |
905e51b3 | 1636 | INIT_DELAYED_WORK(&pool->waker, do_waker); |
991d9fa0 JT |
1637 | spin_lock_init(&pool->lock); |
1638 | bio_list_init(&pool->deferred_bios); | |
1639 | bio_list_init(&pool->deferred_flush_bios); | |
1640 | INIT_LIST_HEAD(&pool->prepared_mappings); | |
104655fd | 1641 | INIT_LIST_HEAD(&pool->prepared_discards); |
991d9fa0 JT |
1642 | pool->low_water_triggered = 0; |
1643 | pool->no_free_space = 0; | |
1644 | bio_list_init(&pool->retry_on_resume_list); | |
44feb387 MS |
1645 | |
1646 | pool->shared_read_ds = dm_deferred_set_create(); | |
1647 | if (!pool->shared_read_ds) { | |
1648 | *error = "Error creating pool's shared read deferred set"; | |
1649 | err_p = ERR_PTR(-ENOMEM); | |
1650 | goto bad_shared_read_ds; | |
1651 | } | |
1652 | ||
1653 | pool->all_io_ds = dm_deferred_set_create(); | |
1654 | if (!pool->all_io_ds) { | |
1655 | *error = "Error creating pool's all io deferred set"; | |
1656 | err_p = ERR_PTR(-ENOMEM); | |
1657 | goto bad_all_io_ds; | |
1658 | } | |
991d9fa0 JT |
1659 | |
1660 | pool->next_mapping = NULL; | |
a24c2569 MS |
1661 | pool->mapping_pool = mempool_create_slab_pool(MAPPING_POOL_SIZE, |
1662 | _new_mapping_cache); | |
991d9fa0 JT |
1663 | if (!pool->mapping_pool) { |
1664 | *error = "Error creating pool's mapping mempool"; | |
1665 | err_p = ERR_PTR(-ENOMEM); | |
1666 | goto bad_mapping_pool; | |
1667 | } | |
1668 | ||
a24c2569 MS |
1669 | pool->endio_hook_pool = mempool_create_slab_pool(ENDIO_HOOK_POOL_SIZE, |
1670 | _endio_hook_cache); | |
991d9fa0 JT |
1671 | if (!pool->endio_hook_pool) { |
1672 | *error = "Error creating pool's endio_hook mempool"; | |
1673 | err_p = ERR_PTR(-ENOMEM); | |
1674 | goto bad_endio_hook_pool; | |
1675 | } | |
1676 | pool->ref_count = 1; | |
905e51b3 | 1677 | pool->last_commit_jiffies = jiffies; |
991d9fa0 JT |
1678 | pool->pool_md = pool_md; |
1679 | pool->md_dev = metadata_dev; | |
1680 | __pool_table_insert(pool); | |
1681 | ||
1682 | return pool; | |
1683 | ||
1684 | bad_endio_hook_pool: | |
1685 | mempool_destroy(pool->mapping_pool); | |
1686 | bad_mapping_pool: | |
44feb387 MS |
1687 | dm_deferred_set_destroy(pool->all_io_ds); |
1688 | bad_all_io_ds: | |
1689 | dm_deferred_set_destroy(pool->shared_read_ds); | |
1690 | bad_shared_read_ds: | |
991d9fa0 JT |
1691 | destroy_workqueue(pool->wq); |
1692 | bad_wq: | |
1693 | dm_kcopyd_client_destroy(pool->copier); | |
1694 | bad_kcopyd_client: | |
44feb387 | 1695 | dm_bio_prison_destroy(pool->prison); |
991d9fa0 JT |
1696 | bad_prison: |
1697 | kfree(pool); | |
1698 | bad_pool: | |
1699 | if (dm_pool_metadata_close(pmd)) | |
1700 | DMWARN("%s: dm_pool_metadata_close() failed.", __func__); | |
1701 | ||
1702 | return err_p; | |
1703 | } | |
1704 | ||
1705 | static void __pool_inc(struct pool *pool) | |
1706 | { | |
1707 | BUG_ON(!mutex_is_locked(&dm_thin_pool_table.mutex)); | |
1708 | pool->ref_count++; | |
1709 | } | |
1710 | ||
1711 | static void __pool_dec(struct pool *pool) | |
1712 | { | |
1713 | BUG_ON(!mutex_is_locked(&dm_thin_pool_table.mutex)); | |
1714 | BUG_ON(!pool->ref_count); | |
1715 | if (!--pool->ref_count) | |
1716 | __pool_destroy(pool); | |
1717 | } | |
1718 | ||
1719 | static struct pool *__pool_find(struct mapped_device *pool_md, | |
1720 | struct block_device *metadata_dev, | |
e49e5829 JT |
1721 | unsigned long block_size, int read_only, |
1722 | char **error, int *created) | |
991d9fa0 JT |
1723 | { |
1724 | struct pool *pool = __pool_table_lookup_metadata_dev(metadata_dev); | |
1725 | ||
1726 | if (pool) { | |
f09996c9 MS |
1727 | if (pool->pool_md != pool_md) { |
1728 | *error = "metadata device already in use by a pool"; | |
991d9fa0 | 1729 | return ERR_PTR(-EBUSY); |
f09996c9 | 1730 | } |
991d9fa0 JT |
1731 | __pool_inc(pool); |
1732 | ||
1733 | } else { | |
1734 | pool = __pool_table_lookup(pool_md); | |
1735 | if (pool) { | |
f09996c9 MS |
1736 | if (pool->md_dev != metadata_dev) { |
1737 | *error = "different pool cannot replace a pool"; | |
991d9fa0 | 1738 | return ERR_PTR(-EINVAL); |
f09996c9 | 1739 | } |
991d9fa0 JT |
1740 | __pool_inc(pool); |
1741 | ||
67e2e2b2 | 1742 | } else { |
e49e5829 | 1743 | pool = pool_create(pool_md, metadata_dev, block_size, read_only, error); |
67e2e2b2 JT |
1744 | *created = 1; |
1745 | } | |
991d9fa0 JT |
1746 | } |
1747 | ||
1748 | return pool; | |
1749 | } | |
1750 | ||
1751 | /*---------------------------------------------------------------- | |
1752 | * Pool target methods | |
1753 | *--------------------------------------------------------------*/ | |
1754 | static void pool_dtr(struct dm_target *ti) | |
1755 | { | |
1756 | struct pool_c *pt = ti->private; | |
1757 | ||
1758 | mutex_lock(&dm_thin_pool_table.mutex); | |
1759 | ||
1760 | unbind_control_target(pt->pool, ti); | |
1761 | __pool_dec(pt->pool); | |
1762 | dm_put_device(ti, pt->metadata_dev); | |
1763 | dm_put_device(ti, pt->data_dev); | |
1764 | kfree(pt); | |
1765 | ||
1766 | mutex_unlock(&dm_thin_pool_table.mutex); | |
1767 | } | |
1768 | ||
991d9fa0 JT |
1769 | static int parse_pool_features(struct dm_arg_set *as, struct pool_features *pf, |
1770 | struct dm_target *ti) | |
1771 | { | |
1772 | int r; | |
1773 | unsigned argc; | |
1774 | const char *arg_name; | |
1775 | ||
1776 | static struct dm_arg _args[] = { | |
67e2e2b2 | 1777 | {0, 3, "Invalid number of pool feature arguments"}, |
991d9fa0 JT |
1778 | }; |
1779 | ||
1780 | /* | |
1781 | * No feature arguments supplied. | |
1782 | */ | |
1783 | if (!as->argc) | |
1784 | return 0; | |
1785 | ||
1786 | r = dm_read_arg_group(_args, as, &argc, &ti->error); | |
1787 | if (r) | |
1788 | return -EINVAL; | |
1789 | ||
1790 | while (argc && !r) { | |
1791 | arg_name = dm_shift_arg(as); | |
1792 | argc--; | |
1793 | ||
e49e5829 | 1794 | if (!strcasecmp(arg_name, "skip_block_zeroing")) |
9bc142dd | 1795 | pf->zero_new_blocks = false; |
e49e5829 JT |
1796 | |
1797 | else if (!strcasecmp(arg_name, "ignore_discard")) | |
9bc142dd | 1798 | pf->discard_enabled = false; |
e49e5829 JT |
1799 | |
1800 | else if (!strcasecmp(arg_name, "no_discard_passdown")) | |
9bc142dd | 1801 | pf->discard_passdown = false; |
991d9fa0 | 1802 | |
e49e5829 JT |
1803 | else if (!strcasecmp(arg_name, "read_only")) |
1804 | pf->mode = PM_READ_ONLY; | |
1805 | ||
1806 | else { | |
1807 | ti->error = "Unrecognised pool feature requested"; | |
1808 | r = -EINVAL; | |
1809 | break; | |
1810 | } | |
991d9fa0 JT |
1811 | } |
1812 | ||
1813 | return r; | |
1814 | } | |
1815 | ||
1816 | /* | |
1817 | * thin-pool <metadata dev> <data dev> | |
1818 | * <data block size (sectors)> | |
1819 | * <low water mark (blocks)> | |
1820 | * [<#feature args> [<arg>]*] | |
1821 | * | |
1822 | * Optional feature arguments are: | |
1823 | * skip_block_zeroing: skips the zeroing of newly-provisioned blocks. | |
67e2e2b2 JT |
1824 | * ignore_discard: disable discard |
1825 | * no_discard_passdown: don't pass discards down to the data device | |
991d9fa0 JT |
1826 | */ |
1827 | static int pool_ctr(struct dm_target *ti, unsigned argc, char **argv) | |
1828 | { | |
67e2e2b2 | 1829 | int r, pool_created = 0; |
991d9fa0 JT |
1830 | struct pool_c *pt; |
1831 | struct pool *pool; | |
1832 | struct pool_features pf; | |
1833 | struct dm_arg_set as; | |
1834 | struct dm_dev *data_dev; | |
1835 | unsigned long block_size; | |
1836 | dm_block_t low_water_blocks; | |
1837 | struct dm_dev *metadata_dev; | |
1838 | sector_t metadata_dev_size; | |
c4a69ecd | 1839 | char b[BDEVNAME_SIZE]; |
991d9fa0 JT |
1840 | |
1841 | /* | |
1842 | * FIXME Remove validation from scope of lock. | |
1843 | */ | |
1844 | mutex_lock(&dm_thin_pool_table.mutex); | |
1845 | ||
1846 | if (argc < 4) { | |
1847 | ti->error = "Invalid argument count"; | |
1848 | r = -EINVAL; | |
1849 | goto out_unlock; | |
1850 | } | |
1851 | as.argc = argc; | |
1852 | as.argv = argv; | |
1853 | ||
1854 | r = dm_get_device(ti, argv[0], FMODE_READ | FMODE_WRITE, &metadata_dev); | |
1855 | if (r) { | |
1856 | ti->error = "Error opening metadata block device"; | |
1857 | goto out_unlock; | |
1858 | } | |
1859 | ||
1860 | metadata_dev_size = i_size_read(metadata_dev->bdev->bd_inode) >> SECTOR_SHIFT; | |
c4a69ecd MS |
1861 | if (metadata_dev_size > THIN_METADATA_MAX_SECTORS_WARNING) |
1862 | DMWARN("Metadata device %s is larger than %u sectors: excess space will not be used.", | |
1863 | bdevname(metadata_dev->bdev, b), THIN_METADATA_MAX_SECTORS); | |
991d9fa0 JT |
1864 | |
1865 | r = dm_get_device(ti, argv[1], FMODE_READ | FMODE_WRITE, &data_dev); | |
1866 | if (r) { | |
1867 | ti->error = "Error getting data device"; | |
1868 | goto out_metadata; | |
1869 | } | |
1870 | ||
1871 | if (kstrtoul(argv[2], 10, &block_size) || !block_size || | |
1872 | block_size < DATA_DEV_BLOCK_SIZE_MIN_SECTORS || | |
1873 | block_size > DATA_DEV_BLOCK_SIZE_MAX_SECTORS || | |
55f2b8bd | 1874 | block_size & (DATA_DEV_BLOCK_SIZE_MIN_SECTORS - 1)) { |
991d9fa0 JT |
1875 | ti->error = "Invalid block size"; |
1876 | r = -EINVAL; | |
1877 | goto out; | |
1878 | } | |
1879 | ||
1880 | if (kstrtoull(argv[3], 10, (unsigned long long *)&low_water_blocks)) { | |
1881 | ti->error = "Invalid low water mark"; | |
1882 | r = -EINVAL; | |
1883 | goto out; | |
1884 | } | |
1885 | ||
1886 | /* | |
1887 | * Set default pool features. | |
1888 | */ | |
67e2e2b2 | 1889 | pool_features_init(&pf); |
991d9fa0 JT |
1890 | |
1891 | dm_consume_args(&as, 4); | |
1892 | r = parse_pool_features(&as, &pf, ti); | |
1893 | if (r) | |
1894 | goto out; | |
1895 | ||
1896 | pt = kzalloc(sizeof(*pt), GFP_KERNEL); | |
1897 | if (!pt) { | |
1898 | r = -ENOMEM; | |
1899 | goto out; | |
1900 | } | |
1901 | ||
1902 | pool = __pool_find(dm_table_get_md(ti->table), metadata_dev->bdev, | |
e49e5829 | 1903 | block_size, pf.mode == PM_READ_ONLY, &ti->error, &pool_created); |
991d9fa0 JT |
1904 | if (IS_ERR(pool)) { |
1905 | r = PTR_ERR(pool); | |
1906 | goto out_free_pt; | |
1907 | } | |
1908 | ||
67e2e2b2 JT |
1909 | /* |
1910 | * 'pool_created' reflects whether this is the first table load. | |
1911 | * Top level discard support is not allowed to be changed after | |
1912 | * initial load. This would require a pool reload to trigger thin | |
1913 | * device changes. | |
1914 | */ | |
1915 | if (!pool_created && pf.discard_enabled != pool->pf.discard_enabled) { | |
1916 | ti->error = "Discard support cannot be disabled once enabled"; | |
1917 | r = -EINVAL; | |
1918 | goto out_flags_changed; | |
1919 | } | |
1920 | ||
991d9fa0 JT |
1921 | pt->pool = pool; |
1922 | pt->ti = ti; | |
1923 | pt->metadata_dev = metadata_dev; | |
1924 | pt->data_dev = data_dev; | |
1925 | pt->low_water_blocks = low_water_blocks; | |
0424caa1 | 1926 | pt->adjusted_pf = pt->requested_pf = pf; |
991d9fa0 | 1927 | ti->num_flush_requests = 1; |
9bc142dd | 1928 | |
67e2e2b2 JT |
1929 | /* |
1930 | * Only need to enable discards if the pool should pass | |
1931 | * them down to the data device. The thin device's discard | |
1932 | * processing will cause mappings to be removed from the btree. | |
1933 | */ | |
1934 | if (pf.discard_enabled && pf.discard_passdown) { | |
1935 | ti->num_discard_requests = 1; | |
9bc142dd | 1936 | |
67e2e2b2 JT |
1937 | /* |
1938 | * Setting 'discards_supported' circumvents the normal | |
1939 | * stacking of discard limits (this keeps the pool and | |
1940 | * thin devices' discard limits consistent). | |
1941 | */ | |
0ac55489 | 1942 | ti->discards_supported = true; |
307615a2 | 1943 | ti->discard_zeroes_data_unsupported = true; |
67e2e2b2 | 1944 | } |
991d9fa0 JT |
1945 | ti->private = pt; |
1946 | ||
1947 | pt->callbacks.congested_fn = pool_is_congested; | |
1948 | dm_table_add_target_callbacks(ti->table, &pt->callbacks); | |
1949 | ||
1950 | mutex_unlock(&dm_thin_pool_table.mutex); | |
1951 | ||
1952 | return 0; | |
1953 | ||
67e2e2b2 JT |
1954 | out_flags_changed: |
1955 | __pool_dec(pool); | |
991d9fa0 JT |
1956 | out_free_pt: |
1957 | kfree(pt); | |
1958 | out: | |
1959 | dm_put_device(ti, data_dev); | |
1960 | out_metadata: | |
1961 | dm_put_device(ti, metadata_dev); | |
1962 | out_unlock: | |
1963 | mutex_unlock(&dm_thin_pool_table.mutex); | |
1964 | ||
1965 | return r; | |
1966 | } | |
1967 | ||
1968 | static int pool_map(struct dm_target *ti, struct bio *bio, | |
1969 | union map_info *map_context) | |
1970 | { | |
1971 | int r; | |
1972 | struct pool_c *pt = ti->private; | |
1973 | struct pool *pool = pt->pool; | |
1974 | unsigned long flags; | |
1975 | ||
1976 | /* | |
1977 | * As this is a singleton target, ti->begin is always zero. | |
1978 | */ | |
1979 | spin_lock_irqsave(&pool->lock, flags); | |
1980 | bio->bi_bdev = pt->data_dev->bdev; | |
1981 | r = DM_MAPIO_REMAPPED; | |
1982 | spin_unlock_irqrestore(&pool->lock, flags); | |
1983 | ||
1984 | return r; | |
1985 | } | |
1986 | ||
1987 | /* | |
1988 | * Retrieves the number of blocks of the data device from | |
1989 | * the superblock and compares it to the actual device size, | |
1990 | * thus resizing the data device in case it has grown. | |
1991 | * | |
1992 | * This both copes with opening preallocated data devices in the ctr | |
1993 | * being followed by a resume | |
1994 | * -and- | |
1995 | * calling the resume method individually after userspace has | |
1996 | * grown the data device in reaction to a table event. | |
1997 | */ | |
1998 | static int pool_preresume(struct dm_target *ti) | |
1999 | { | |
2000 | int r; | |
2001 | struct pool_c *pt = ti->private; | |
2002 | struct pool *pool = pt->pool; | |
55f2b8bd MS |
2003 | sector_t data_size = ti->len; |
2004 | dm_block_t sb_data_size; | |
991d9fa0 JT |
2005 | |
2006 | /* | |
2007 | * Take control of the pool object. | |
2008 | */ | |
2009 | r = bind_control_target(pool, ti); | |
2010 | if (r) | |
2011 | return r; | |
2012 | ||
55f2b8bd MS |
2013 | (void) sector_div(data_size, pool->sectors_per_block); |
2014 | ||
991d9fa0 JT |
2015 | r = dm_pool_get_data_dev_size(pool->pmd, &sb_data_size); |
2016 | if (r) { | |
2017 | DMERR("failed to retrieve data device size"); | |
2018 | return r; | |
2019 | } | |
2020 | ||
2021 | if (data_size < sb_data_size) { | |
2022 | DMERR("pool target too small, is %llu blocks (expected %llu)", | |
55f2b8bd | 2023 | (unsigned long long)data_size, sb_data_size); |
991d9fa0 JT |
2024 | return -EINVAL; |
2025 | ||
2026 | } else if (data_size > sb_data_size) { | |
2027 | r = dm_pool_resize_data_dev(pool->pmd, data_size); | |
2028 | if (r) { | |
2029 | DMERR("failed to resize data device"); | |
e49e5829 JT |
2030 | /* FIXME Stricter than necessary: Rollback transaction instead here */ |
2031 | set_pool_mode(pool, PM_READ_ONLY); | |
991d9fa0 JT |
2032 | return r; |
2033 | } | |
2034 | ||
e49e5829 | 2035 | (void) commit_or_fallback(pool); |
991d9fa0 JT |
2036 | } |
2037 | ||
2038 | return 0; | |
2039 | } | |
2040 | ||
2041 | static void pool_resume(struct dm_target *ti) | |
2042 | { | |
2043 | struct pool_c *pt = ti->private; | |
2044 | struct pool *pool = pt->pool; | |
2045 | unsigned long flags; | |
2046 | ||
2047 | spin_lock_irqsave(&pool->lock, flags); | |
2048 | pool->low_water_triggered = 0; | |
2049 | pool->no_free_space = 0; | |
2050 | __requeue_bios(pool); | |
2051 | spin_unlock_irqrestore(&pool->lock, flags); | |
2052 | ||
905e51b3 | 2053 | do_waker(&pool->waker.work); |
991d9fa0 JT |
2054 | } |
2055 | ||
2056 | static void pool_postsuspend(struct dm_target *ti) | |
2057 | { | |
991d9fa0 JT |
2058 | struct pool_c *pt = ti->private; |
2059 | struct pool *pool = pt->pool; | |
2060 | ||
905e51b3 | 2061 | cancel_delayed_work(&pool->waker); |
991d9fa0 | 2062 | flush_workqueue(pool->wq); |
e49e5829 | 2063 | (void) commit_or_fallback(pool); |
991d9fa0 JT |
2064 | } |
2065 | ||
2066 | static int check_arg_count(unsigned argc, unsigned args_required) | |
2067 | { | |
2068 | if (argc != args_required) { | |
2069 | DMWARN("Message received with %u arguments instead of %u.", | |
2070 | argc, args_required); | |
2071 | return -EINVAL; | |
2072 | } | |
2073 | ||
2074 | return 0; | |
2075 | } | |
2076 | ||
2077 | static int read_dev_id(char *arg, dm_thin_id *dev_id, int warning) | |
2078 | { | |
2079 | if (!kstrtoull(arg, 10, (unsigned long long *)dev_id) && | |
2080 | *dev_id <= MAX_DEV_ID) | |
2081 | return 0; | |
2082 | ||
2083 | if (warning) | |
2084 | DMWARN("Message received with invalid device id: %s", arg); | |
2085 | ||
2086 | return -EINVAL; | |
2087 | } | |
2088 | ||
2089 | static int process_create_thin_mesg(unsigned argc, char **argv, struct pool *pool) | |
2090 | { | |
2091 | dm_thin_id dev_id; | |
2092 | int r; | |
2093 | ||
2094 | r = check_arg_count(argc, 2); | |
2095 | if (r) | |
2096 | return r; | |
2097 | ||
2098 | r = read_dev_id(argv[1], &dev_id, 1); | |
2099 | if (r) | |
2100 | return r; | |
2101 | ||
2102 | r = dm_pool_create_thin(pool->pmd, dev_id); | |
2103 | if (r) { | |
2104 | DMWARN("Creation of new thinly-provisioned device with id %s failed.", | |
2105 | argv[1]); | |
2106 | return r; | |
2107 | } | |
2108 | ||
2109 | return 0; | |
2110 | } | |
2111 | ||
2112 | static int process_create_snap_mesg(unsigned argc, char **argv, struct pool *pool) | |
2113 | { | |
2114 | dm_thin_id dev_id; | |
2115 | dm_thin_id origin_dev_id; | |
2116 | int r; | |
2117 | ||
2118 | r = check_arg_count(argc, 3); | |
2119 | if (r) | |
2120 | return r; | |
2121 | ||
2122 | r = read_dev_id(argv[1], &dev_id, 1); | |
2123 | if (r) | |
2124 | return r; | |
2125 | ||
2126 | r = read_dev_id(argv[2], &origin_dev_id, 1); | |
2127 | if (r) | |
2128 | return r; | |
2129 | ||
2130 | r = dm_pool_create_snap(pool->pmd, dev_id, origin_dev_id); | |
2131 | if (r) { | |
2132 | DMWARN("Creation of new snapshot %s of device %s failed.", | |
2133 | argv[1], argv[2]); | |
2134 | return r; | |
2135 | } | |
2136 | ||
2137 | return 0; | |
2138 | } | |
2139 | ||
2140 | static int process_delete_mesg(unsigned argc, char **argv, struct pool *pool) | |
2141 | { | |
2142 | dm_thin_id dev_id; | |
2143 | int r; | |
2144 | ||
2145 | r = check_arg_count(argc, 2); | |
2146 | if (r) | |
2147 | return r; | |
2148 | ||
2149 | r = read_dev_id(argv[1], &dev_id, 1); | |
2150 | if (r) | |
2151 | return r; | |
2152 | ||
2153 | r = dm_pool_delete_thin_device(pool->pmd, dev_id); | |
2154 | if (r) | |
2155 | DMWARN("Deletion of thin device %s failed.", argv[1]); | |
2156 | ||
2157 | return r; | |
2158 | } | |
2159 | ||
2160 | static int process_set_transaction_id_mesg(unsigned argc, char **argv, struct pool *pool) | |
2161 | { | |
2162 | dm_thin_id old_id, new_id; | |
2163 | int r; | |
2164 | ||
2165 | r = check_arg_count(argc, 3); | |
2166 | if (r) | |
2167 | return r; | |
2168 | ||
2169 | if (kstrtoull(argv[1], 10, (unsigned long long *)&old_id)) { | |
2170 | DMWARN("set_transaction_id message: Unrecognised id %s.", argv[1]); | |
2171 | return -EINVAL; | |
2172 | } | |
2173 | ||
2174 | if (kstrtoull(argv[2], 10, (unsigned long long *)&new_id)) { | |
2175 | DMWARN("set_transaction_id message: Unrecognised new id %s.", argv[2]); | |
2176 | return -EINVAL; | |
2177 | } | |
2178 | ||
2179 | r = dm_pool_set_metadata_transaction_id(pool->pmd, old_id, new_id); | |
2180 | if (r) { | |
2181 | DMWARN("Failed to change transaction id from %s to %s.", | |
2182 | argv[1], argv[2]); | |
2183 | return r; | |
2184 | } | |
2185 | ||
2186 | return 0; | |
2187 | } | |
2188 | ||
cc8394d8 JT |
2189 | static int process_reserve_metadata_snap_mesg(unsigned argc, char **argv, struct pool *pool) |
2190 | { | |
2191 | int r; | |
2192 | ||
2193 | r = check_arg_count(argc, 1); | |
2194 | if (r) | |
2195 | return r; | |
2196 | ||
e49e5829 | 2197 | (void) commit_or_fallback(pool); |
0d200aef | 2198 | |
cc8394d8 JT |
2199 | r = dm_pool_reserve_metadata_snap(pool->pmd); |
2200 | if (r) | |
2201 | DMWARN("reserve_metadata_snap message failed."); | |
2202 | ||
2203 | return r; | |
2204 | } | |
2205 | ||
2206 | static int process_release_metadata_snap_mesg(unsigned argc, char **argv, struct pool *pool) | |
2207 | { | |
2208 | int r; | |
2209 | ||
2210 | r = check_arg_count(argc, 1); | |
2211 | if (r) | |
2212 | return r; | |
2213 | ||
2214 | r = dm_pool_release_metadata_snap(pool->pmd); | |
2215 | if (r) | |
2216 | DMWARN("release_metadata_snap message failed."); | |
2217 | ||
2218 | return r; | |
2219 | } | |
2220 | ||
991d9fa0 JT |
2221 | /* |
2222 | * Messages supported: | |
2223 | * create_thin <dev_id> | |
2224 | * create_snap <dev_id> <origin_id> | |
2225 | * delete <dev_id> | |
2226 | * trim <dev_id> <new_size_in_sectors> | |
2227 | * set_transaction_id <current_trans_id> <new_trans_id> | |
cc8394d8 JT |
2228 | * reserve_metadata_snap |
2229 | * release_metadata_snap | |
991d9fa0 JT |
2230 | */ |
2231 | static int pool_message(struct dm_target *ti, unsigned argc, char **argv) | |
2232 | { | |
2233 | int r = -EINVAL; | |
2234 | struct pool_c *pt = ti->private; | |
2235 | struct pool *pool = pt->pool; | |
2236 | ||
2237 | if (!strcasecmp(argv[0], "create_thin")) | |
2238 | r = process_create_thin_mesg(argc, argv, pool); | |
2239 | ||
2240 | else if (!strcasecmp(argv[0], "create_snap")) | |
2241 | r = process_create_snap_mesg(argc, argv, pool); | |
2242 | ||
2243 | else if (!strcasecmp(argv[0], "delete")) | |
2244 | r = process_delete_mesg(argc, argv, pool); | |
2245 | ||
2246 | else if (!strcasecmp(argv[0], "set_transaction_id")) | |
2247 | r = process_set_transaction_id_mesg(argc, argv, pool); | |
2248 | ||
cc8394d8 JT |
2249 | else if (!strcasecmp(argv[0], "reserve_metadata_snap")) |
2250 | r = process_reserve_metadata_snap_mesg(argc, argv, pool); | |
2251 | ||
2252 | else if (!strcasecmp(argv[0], "release_metadata_snap")) | |
2253 | r = process_release_metadata_snap_mesg(argc, argv, pool); | |
2254 | ||
991d9fa0 JT |
2255 | else |
2256 | DMWARN("Unrecognised thin pool target message received: %s", argv[0]); | |
2257 | ||
e49e5829 JT |
2258 | if (!r) |
2259 | (void) commit_or_fallback(pool); | |
991d9fa0 JT |
2260 | |
2261 | return r; | |
2262 | } | |
2263 | ||
e49e5829 JT |
2264 | static void emit_flags(struct pool_features *pf, char *result, |
2265 | unsigned sz, unsigned maxlen) | |
2266 | { | |
2267 | unsigned count = !pf->zero_new_blocks + !pf->discard_enabled + | |
2268 | !pf->discard_passdown + (pf->mode == PM_READ_ONLY); | |
2269 | DMEMIT("%u ", count); | |
2270 | ||
2271 | if (!pf->zero_new_blocks) | |
2272 | DMEMIT("skip_block_zeroing "); | |
2273 | ||
2274 | if (!pf->discard_enabled) | |
2275 | DMEMIT("ignore_discard "); | |
2276 | ||
2277 | if (!pf->discard_passdown) | |
2278 | DMEMIT("no_discard_passdown "); | |
2279 | ||
2280 | if (pf->mode == PM_READ_ONLY) | |
2281 | DMEMIT("read_only "); | |
2282 | } | |
2283 | ||
991d9fa0 JT |
2284 | /* |
2285 | * Status line is: | |
2286 | * <transaction id> <used metadata sectors>/<total metadata sectors> | |
2287 | * <used data sectors>/<total data sectors> <held metadata root> | |
2288 | */ | |
2289 | static int pool_status(struct dm_target *ti, status_type_t type, | |
1f4e0ff0 | 2290 | unsigned status_flags, char *result, unsigned maxlen) |
991d9fa0 | 2291 | { |
e49e5829 | 2292 | int r; |
991d9fa0 JT |
2293 | unsigned sz = 0; |
2294 | uint64_t transaction_id; | |
2295 | dm_block_t nr_free_blocks_data; | |
2296 | dm_block_t nr_free_blocks_metadata; | |
2297 | dm_block_t nr_blocks_data; | |
2298 | dm_block_t nr_blocks_metadata; | |
2299 | dm_block_t held_root; | |
2300 | char buf[BDEVNAME_SIZE]; | |
2301 | char buf2[BDEVNAME_SIZE]; | |
2302 | struct pool_c *pt = ti->private; | |
2303 | struct pool *pool = pt->pool; | |
2304 | ||
2305 | switch (type) { | |
2306 | case STATUSTYPE_INFO: | |
e49e5829 JT |
2307 | if (get_pool_mode(pool) == PM_FAIL) { |
2308 | DMEMIT("Fail"); | |
2309 | break; | |
2310 | } | |
2311 | ||
1f4e0ff0 AK |
2312 | /* Commit to ensure statistics aren't out-of-date */ |
2313 | if (!(status_flags & DM_STATUS_NOFLUSH_FLAG) && !dm_suspended(ti)) | |
2314 | (void) commit_or_fallback(pool); | |
2315 | ||
991d9fa0 JT |
2316 | r = dm_pool_get_metadata_transaction_id(pool->pmd, |
2317 | &transaction_id); | |
2318 | if (r) | |
2319 | return r; | |
2320 | ||
2321 | r = dm_pool_get_free_metadata_block_count(pool->pmd, | |
2322 | &nr_free_blocks_metadata); | |
2323 | if (r) | |
2324 | return r; | |
2325 | ||
2326 | r = dm_pool_get_metadata_dev_size(pool->pmd, &nr_blocks_metadata); | |
2327 | if (r) | |
2328 | return r; | |
2329 | ||
2330 | r = dm_pool_get_free_block_count(pool->pmd, | |
2331 | &nr_free_blocks_data); | |
2332 | if (r) | |
2333 | return r; | |
2334 | ||
2335 | r = dm_pool_get_data_dev_size(pool->pmd, &nr_blocks_data); | |
2336 | if (r) | |
2337 | return r; | |
2338 | ||
cc8394d8 | 2339 | r = dm_pool_get_metadata_snap(pool->pmd, &held_root); |
991d9fa0 JT |
2340 | if (r) |
2341 | return r; | |
2342 | ||
2343 | DMEMIT("%llu %llu/%llu %llu/%llu ", | |
2344 | (unsigned long long)transaction_id, | |
2345 | (unsigned long long)(nr_blocks_metadata - nr_free_blocks_metadata), | |
2346 | (unsigned long long)nr_blocks_metadata, | |
2347 | (unsigned long long)(nr_blocks_data - nr_free_blocks_data), | |
2348 | (unsigned long long)nr_blocks_data); | |
2349 | ||
2350 | if (held_root) | |
e49e5829 JT |
2351 | DMEMIT("%llu ", held_root); |
2352 | else | |
2353 | DMEMIT("- "); | |
2354 | ||
2355 | if (pool->pf.mode == PM_READ_ONLY) | |
2356 | DMEMIT("ro "); | |
991d9fa0 | 2357 | else |
e49e5829 JT |
2358 | DMEMIT("rw "); |
2359 | ||
2360 | if (pool->pf.discard_enabled && pool->pf.discard_passdown) | |
2361 | DMEMIT("discard_passdown"); | |
2362 | else | |
2363 | DMEMIT("no_discard_passdown"); | |
991d9fa0 JT |
2364 | |
2365 | break; | |
2366 | ||
2367 | case STATUSTYPE_TABLE: | |
2368 | DMEMIT("%s %s %lu %llu ", | |
2369 | format_dev_t(buf, pt->metadata_dev->bdev->bd_dev), | |
2370 | format_dev_t(buf2, pt->data_dev->bdev->bd_dev), | |
2371 | (unsigned long)pool->sectors_per_block, | |
2372 | (unsigned long long)pt->low_water_blocks); | |
0424caa1 | 2373 | emit_flags(&pt->requested_pf, result, sz, maxlen); |
991d9fa0 JT |
2374 | break; |
2375 | } | |
2376 | ||
2377 | return 0; | |
2378 | } | |
2379 | ||
2380 | static int pool_iterate_devices(struct dm_target *ti, | |
2381 | iterate_devices_callout_fn fn, void *data) | |
2382 | { | |
2383 | struct pool_c *pt = ti->private; | |
2384 | ||
2385 | return fn(ti, pt->data_dev, 0, ti->len, data); | |
2386 | } | |
2387 | ||
2388 | static int pool_merge(struct dm_target *ti, struct bvec_merge_data *bvm, | |
2389 | struct bio_vec *biovec, int max_size) | |
2390 | { | |
2391 | struct pool_c *pt = ti->private; | |
2392 | struct request_queue *q = bdev_get_queue(pt->data_dev->bdev); | |
2393 | ||
2394 | if (!q->merge_bvec_fn) | |
2395 | return max_size; | |
2396 | ||
2397 | bvm->bi_bdev = pt->data_dev->bdev; | |
2398 | ||
2399 | return min(max_size, q->merge_bvec_fn(q, bvm, biovec)); | |
2400 | } | |
2401 | ||
28eed34e MS |
2402 | static bool block_size_is_power_of_two(struct pool *pool) |
2403 | { | |
2404 | return pool->sectors_per_block_shift >= 0; | |
2405 | } | |
2406 | ||
0424caa1 | 2407 | static void set_discard_limits(struct pool_c *pt, struct queue_limits *limits) |
104655fd | 2408 | { |
0424caa1 MS |
2409 | struct pool *pool = pt->pool; |
2410 | struct queue_limits *data_limits; | |
2411 | ||
104655fd JT |
2412 | limits->max_discard_sectors = pool->sectors_per_block; |
2413 | ||
2414 | /* | |
0424caa1 | 2415 | * discard_granularity is just a hint, and not enforced. |
104655fd | 2416 | */ |
0424caa1 MS |
2417 | if (pt->adjusted_pf.discard_passdown) { |
2418 | data_limits = &bdev_get_queue(pt->data_dev->bdev)->limits; | |
2419 | limits->discard_granularity = data_limits->discard_granularity; | |
28eed34e | 2420 | } else if (block_size_is_power_of_two(pool)) |
0424caa1 | 2421 | limits->discard_granularity = pool->sectors_per_block << SECTOR_SHIFT; |
28eed34e MS |
2422 | else |
2423 | /* | |
2424 | * Use largest power of 2 that is a factor of sectors_per_block | |
2425 | * but at least DATA_DEV_BLOCK_SIZE_MIN_SECTORS. | |
2426 | */ | |
2427 | limits->discard_granularity = max(1 << (ffs(pool->sectors_per_block) - 1), | |
2428 | DATA_DEV_BLOCK_SIZE_MIN_SECTORS) << SECTOR_SHIFT; | |
104655fd JT |
2429 | } |
2430 | ||
991d9fa0 JT |
2431 | static void pool_io_hints(struct dm_target *ti, struct queue_limits *limits) |
2432 | { | |
2433 | struct pool_c *pt = ti->private; | |
2434 | struct pool *pool = pt->pool; | |
2435 | ||
2436 | blk_limits_io_min(limits, 0); | |
2437 | blk_limits_io_opt(limits, pool->sectors_per_block << SECTOR_SHIFT); | |
0424caa1 MS |
2438 | |
2439 | /* | |
2440 | * pt->adjusted_pf is a staging area for the actual features to use. | |
2441 | * They get transferred to the live pool in bind_control_target() | |
2442 | * called from pool_preresume(). | |
2443 | */ | |
2444 | if (!pt->adjusted_pf.discard_enabled) | |
2445 | return; | |
2446 | ||
2447 | disable_passdown_if_not_supported(pt); | |
2448 | ||
2449 | set_discard_limits(pt, limits); | |
991d9fa0 JT |
2450 | } |
2451 | ||
2452 | static struct target_type pool_target = { | |
2453 | .name = "thin-pool", | |
2454 | .features = DM_TARGET_SINGLETON | DM_TARGET_ALWAYS_WRITEABLE | | |
2455 | DM_TARGET_IMMUTABLE, | |
4f81a417 | 2456 | .version = {1, 5, 0}, |
991d9fa0 JT |
2457 | .module = THIS_MODULE, |
2458 | .ctr = pool_ctr, | |
2459 | .dtr = pool_dtr, | |
2460 | .map = pool_map, | |
2461 | .postsuspend = pool_postsuspend, | |
2462 | .preresume = pool_preresume, | |
2463 | .resume = pool_resume, | |
2464 | .message = pool_message, | |
2465 | .status = pool_status, | |
2466 | .merge = pool_merge, | |
2467 | .iterate_devices = pool_iterate_devices, | |
2468 | .io_hints = pool_io_hints, | |
2469 | }; | |
2470 | ||
2471 | /*---------------------------------------------------------------- | |
2472 | * Thin target methods | |
2473 | *--------------------------------------------------------------*/ | |
2474 | static void thin_dtr(struct dm_target *ti) | |
2475 | { | |
2476 | struct thin_c *tc = ti->private; | |
2477 | ||
2478 | mutex_lock(&dm_thin_pool_table.mutex); | |
2479 | ||
2480 | __pool_dec(tc->pool); | |
2481 | dm_pool_close_thin_device(tc->td); | |
2482 | dm_put_device(ti, tc->pool_dev); | |
2dd9c257 JT |
2483 | if (tc->origin_dev) |
2484 | dm_put_device(ti, tc->origin_dev); | |
991d9fa0 JT |
2485 | kfree(tc); |
2486 | ||
2487 | mutex_unlock(&dm_thin_pool_table.mutex); | |
2488 | } | |
2489 | ||
2490 | /* | |
2491 | * Thin target parameters: | |
2492 | * | |
2dd9c257 | 2493 | * <pool_dev> <dev_id> [origin_dev] |
991d9fa0 JT |
2494 | * |
2495 | * pool_dev: the path to the pool (eg, /dev/mapper/my_pool) | |
2496 | * dev_id: the internal device identifier | |
2dd9c257 | 2497 | * origin_dev: a device external to the pool that should act as the origin |
67e2e2b2 JT |
2498 | * |
2499 | * If the pool device has discards disabled, they get disabled for the thin | |
2500 | * device as well. | |
991d9fa0 JT |
2501 | */ |
2502 | static int thin_ctr(struct dm_target *ti, unsigned argc, char **argv) | |
2503 | { | |
2504 | int r; | |
2505 | struct thin_c *tc; | |
2dd9c257 | 2506 | struct dm_dev *pool_dev, *origin_dev; |
991d9fa0 JT |
2507 | struct mapped_device *pool_md; |
2508 | ||
2509 | mutex_lock(&dm_thin_pool_table.mutex); | |
2510 | ||
2dd9c257 | 2511 | if (argc != 2 && argc != 3) { |
991d9fa0 JT |
2512 | ti->error = "Invalid argument count"; |
2513 | r = -EINVAL; | |
2514 | goto out_unlock; | |
2515 | } | |
2516 | ||
2517 | tc = ti->private = kzalloc(sizeof(*tc), GFP_KERNEL); | |
2518 | if (!tc) { | |
2519 | ti->error = "Out of memory"; | |
2520 | r = -ENOMEM; | |
2521 | goto out_unlock; | |
2522 | } | |
2523 | ||
2dd9c257 JT |
2524 | if (argc == 3) { |
2525 | r = dm_get_device(ti, argv[2], FMODE_READ, &origin_dev); | |
2526 | if (r) { | |
2527 | ti->error = "Error opening origin device"; | |
2528 | goto bad_origin_dev; | |
2529 | } | |
2530 | tc->origin_dev = origin_dev; | |
2531 | } | |
2532 | ||
991d9fa0 JT |
2533 | r = dm_get_device(ti, argv[0], dm_table_get_mode(ti->table), &pool_dev); |
2534 | if (r) { | |
2535 | ti->error = "Error opening pool device"; | |
2536 | goto bad_pool_dev; | |
2537 | } | |
2538 | tc->pool_dev = pool_dev; | |
2539 | ||
2540 | if (read_dev_id(argv[1], (unsigned long long *)&tc->dev_id, 0)) { | |
2541 | ti->error = "Invalid device id"; | |
2542 | r = -EINVAL; | |
2543 | goto bad_common; | |
2544 | } | |
2545 | ||
2546 | pool_md = dm_get_md(tc->pool_dev->bdev->bd_dev); | |
2547 | if (!pool_md) { | |
2548 | ti->error = "Couldn't get pool mapped device"; | |
2549 | r = -EINVAL; | |
2550 | goto bad_common; | |
2551 | } | |
2552 | ||
2553 | tc->pool = __pool_table_lookup(pool_md); | |
2554 | if (!tc->pool) { | |
2555 | ti->error = "Couldn't find pool object"; | |
2556 | r = -EINVAL; | |
2557 | goto bad_pool_lookup; | |
2558 | } | |
2559 | __pool_inc(tc->pool); | |
2560 | ||
e49e5829 JT |
2561 | if (get_pool_mode(tc->pool) == PM_FAIL) { |
2562 | ti->error = "Couldn't open thin device, Pool is in fail mode"; | |
2563 | goto bad_thin_open; | |
2564 | } | |
2565 | ||
991d9fa0 JT |
2566 | r = dm_pool_open_thin_device(tc->pool->pmd, tc->dev_id, &tc->td); |
2567 | if (r) { | |
2568 | ti->error = "Couldn't open thin internal device"; | |
2569 | goto bad_thin_open; | |
2570 | } | |
2571 | ||
542f9038 MS |
2572 | r = dm_set_target_max_io_len(ti, tc->pool->sectors_per_block); |
2573 | if (r) | |
2574 | goto bad_thin_open; | |
2575 | ||
991d9fa0 | 2576 | ti->num_flush_requests = 1; |
16ad3d10 | 2577 | ti->flush_supported = true; |
67e2e2b2 JT |
2578 | |
2579 | /* In case the pool supports discards, pass them on. */ | |
2580 | if (tc->pool->pf.discard_enabled) { | |
0ac55489 | 2581 | ti->discards_supported = true; |
67e2e2b2 | 2582 | ti->num_discard_requests = 1; |
0ac55489 | 2583 | ti->discard_zeroes_data_unsupported = true; |
49296309 | 2584 | /* Discard requests must be split on a block boundary */ |
0ac55489 | 2585 | ti->split_discard_requests = true; |
67e2e2b2 | 2586 | } |
991d9fa0 JT |
2587 | |
2588 | dm_put(pool_md); | |
2589 | ||
2590 | mutex_unlock(&dm_thin_pool_table.mutex); | |
2591 | ||
2592 | return 0; | |
2593 | ||
2594 | bad_thin_open: | |
2595 | __pool_dec(tc->pool); | |
2596 | bad_pool_lookup: | |
2597 | dm_put(pool_md); | |
2598 | bad_common: | |
2599 | dm_put_device(ti, tc->pool_dev); | |
2600 | bad_pool_dev: | |
2dd9c257 JT |
2601 | if (tc->origin_dev) |
2602 | dm_put_device(ti, tc->origin_dev); | |
2603 | bad_origin_dev: | |
991d9fa0 JT |
2604 | kfree(tc); |
2605 | out_unlock: | |
2606 | mutex_unlock(&dm_thin_pool_table.mutex); | |
2607 | ||
2608 | return r; | |
2609 | } | |
2610 | ||
2611 | static int thin_map(struct dm_target *ti, struct bio *bio, | |
2612 | union map_info *map_context) | |
2613 | { | |
6efd6e83 | 2614 | bio->bi_sector = dm_target_offset(ti, bio->bi_sector); |
991d9fa0 JT |
2615 | |
2616 | return thin_bio_map(ti, bio, map_context); | |
2617 | } | |
2618 | ||
eb2aa48d JT |
2619 | static int thin_endio(struct dm_target *ti, |
2620 | struct bio *bio, int err, | |
2621 | union map_info *map_context) | |
2622 | { | |
2623 | unsigned long flags; | |
a24c2569 | 2624 | struct dm_thin_endio_hook *h = map_context->ptr; |
eb2aa48d | 2625 | struct list_head work; |
a24c2569 | 2626 | struct dm_thin_new_mapping *m, *tmp; |
eb2aa48d JT |
2627 | struct pool *pool = h->tc->pool; |
2628 | ||
2629 | if (h->shared_read_entry) { | |
2630 | INIT_LIST_HEAD(&work); | |
44feb387 | 2631 | dm_deferred_entry_dec(h->shared_read_entry, &work); |
eb2aa48d JT |
2632 | |
2633 | spin_lock_irqsave(&pool->lock, flags); | |
2634 | list_for_each_entry_safe(m, tmp, &work, list) { | |
2635 | list_del(&m->list); | |
2636 | m->quiesced = 1; | |
2637 | __maybe_add_mapping(m); | |
2638 | } | |
2639 | spin_unlock_irqrestore(&pool->lock, flags); | |
2640 | } | |
2641 | ||
104655fd JT |
2642 | if (h->all_io_entry) { |
2643 | INIT_LIST_HEAD(&work); | |
44feb387 | 2644 | dm_deferred_entry_dec(h->all_io_entry, &work); |
c3a0ce2e | 2645 | spin_lock_irqsave(&pool->lock, flags); |
104655fd JT |
2646 | list_for_each_entry_safe(m, tmp, &work, list) |
2647 | list_add(&m->list, &pool->prepared_discards); | |
c3a0ce2e | 2648 | spin_unlock_irqrestore(&pool->lock, flags); |
104655fd JT |
2649 | } |
2650 | ||
eb2aa48d JT |
2651 | mempool_free(h, pool->endio_hook_pool); |
2652 | ||
2653 | return 0; | |
2654 | } | |
2655 | ||
991d9fa0 JT |
2656 | static void thin_postsuspend(struct dm_target *ti) |
2657 | { | |
2658 | if (dm_noflush_suspending(ti)) | |
2659 | requeue_io((struct thin_c *)ti->private); | |
2660 | } | |
2661 | ||
2662 | /* | |
2663 | * <nr mapped sectors> <highest mapped sector> | |
2664 | */ | |
2665 | static int thin_status(struct dm_target *ti, status_type_t type, | |
1f4e0ff0 | 2666 | unsigned status_flags, char *result, unsigned maxlen) |
991d9fa0 JT |
2667 | { |
2668 | int r; | |
2669 | ssize_t sz = 0; | |
2670 | dm_block_t mapped, highest; | |
2671 | char buf[BDEVNAME_SIZE]; | |
2672 | struct thin_c *tc = ti->private; | |
2673 | ||
e49e5829 JT |
2674 | if (get_pool_mode(tc->pool) == PM_FAIL) { |
2675 | DMEMIT("Fail"); | |
2676 | return 0; | |
2677 | } | |
2678 | ||
991d9fa0 JT |
2679 | if (!tc->td) |
2680 | DMEMIT("-"); | |
2681 | else { | |
2682 | switch (type) { | |
2683 | case STATUSTYPE_INFO: | |
2684 | r = dm_thin_get_mapped_count(tc->td, &mapped); | |
2685 | if (r) | |
2686 | return r; | |
2687 | ||
2688 | r = dm_thin_get_highest_mapped_block(tc->td, &highest); | |
2689 | if (r < 0) | |
2690 | return r; | |
2691 | ||
2692 | DMEMIT("%llu ", mapped * tc->pool->sectors_per_block); | |
2693 | if (r) | |
2694 | DMEMIT("%llu", ((highest + 1) * | |
2695 | tc->pool->sectors_per_block) - 1); | |
2696 | else | |
2697 | DMEMIT("-"); | |
2698 | break; | |
2699 | ||
2700 | case STATUSTYPE_TABLE: | |
2701 | DMEMIT("%s %lu", | |
2702 | format_dev_t(buf, tc->pool_dev->bdev->bd_dev), | |
2703 | (unsigned long) tc->dev_id); | |
2dd9c257 JT |
2704 | if (tc->origin_dev) |
2705 | DMEMIT(" %s", format_dev_t(buf, tc->origin_dev->bdev->bd_dev)); | |
991d9fa0 JT |
2706 | break; |
2707 | } | |
2708 | } | |
2709 | ||
2710 | return 0; | |
2711 | } | |
2712 | ||
2713 | static int thin_iterate_devices(struct dm_target *ti, | |
2714 | iterate_devices_callout_fn fn, void *data) | |
2715 | { | |
55f2b8bd | 2716 | sector_t blocks; |
991d9fa0 | 2717 | struct thin_c *tc = ti->private; |
55f2b8bd | 2718 | struct pool *pool = tc->pool; |
991d9fa0 JT |
2719 | |
2720 | /* | |
2721 | * We can't call dm_pool_get_data_dev_size() since that blocks. So | |
2722 | * we follow a more convoluted path through to the pool's target. | |
2723 | */ | |
55f2b8bd | 2724 | if (!pool->ti) |
991d9fa0 JT |
2725 | return 0; /* nothing is bound */ |
2726 | ||
55f2b8bd MS |
2727 | blocks = pool->ti->len; |
2728 | (void) sector_div(blocks, pool->sectors_per_block); | |
991d9fa0 | 2729 | if (blocks) |
55f2b8bd | 2730 | return fn(ti, tc->pool_dev, 0, pool->sectors_per_block * blocks, data); |
991d9fa0 JT |
2731 | |
2732 | return 0; | |
2733 | } | |
2734 | ||
0424caa1 MS |
2735 | /* |
2736 | * A thin device always inherits its queue limits from its pool. | |
2737 | */ | |
991d9fa0 JT |
2738 | static void thin_io_hints(struct dm_target *ti, struct queue_limits *limits) |
2739 | { | |
2740 | struct thin_c *tc = ti->private; | |
2741 | ||
0424caa1 | 2742 | *limits = bdev_get_queue(tc->pool_dev->bdev)->limits; |
991d9fa0 JT |
2743 | } |
2744 | ||
2745 | static struct target_type thin_target = { | |
2746 | .name = "thin", | |
4f81a417 | 2747 | .version = {1, 5, 0}, |
991d9fa0 JT |
2748 | .module = THIS_MODULE, |
2749 | .ctr = thin_ctr, | |
2750 | .dtr = thin_dtr, | |
2751 | .map = thin_map, | |
eb2aa48d | 2752 | .end_io = thin_endio, |
991d9fa0 JT |
2753 | .postsuspend = thin_postsuspend, |
2754 | .status = thin_status, | |
2755 | .iterate_devices = thin_iterate_devices, | |
2756 | .io_hints = thin_io_hints, | |
2757 | }; | |
2758 | ||
2759 | /*----------------------------------------------------------------*/ | |
2760 | ||
2761 | static int __init dm_thin_init(void) | |
2762 | { | |
2763 | int r; | |
2764 | ||
2765 | pool_table_init(); | |
2766 | ||
2767 | r = dm_register_target(&thin_target); | |
2768 | if (r) | |
2769 | return r; | |
2770 | ||
2771 | r = dm_register_target(&pool_target); | |
2772 | if (r) | |
a24c2569 MS |
2773 | goto bad_pool_target; |
2774 | ||
2775 | r = -ENOMEM; | |
2776 | ||
a24c2569 MS |
2777 | _new_mapping_cache = KMEM_CACHE(dm_thin_new_mapping, 0); |
2778 | if (!_new_mapping_cache) | |
2779 | goto bad_new_mapping_cache; | |
2780 | ||
2781 | _endio_hook_cache = KMEM_CACHE(dm_thin_endio_hook, 0); | |
2782 | if (!_endio_hook_cache) | |
2783 | goto bad_endio_hook_cache; | |
2784 | ||
2785 | return 0; | |
2786 | ||
2787 | bad_endio_hook_cache: | |
2788 | kmem_cache_destroy(_new_mapping_cache); | |
2789 | bad_new_mapping_cache: | |
a24c2569 MS |
2790 | dm_unregister_target(&pool_target); |
2791 | bad_pool_target: | |
2792 | dm_unregister_target(&thin_target); | |
991d9fa0 JT |
2793 | |
2794 | return r; | |
2795 | } | |
2796 | ||
2797 | static void dm_thin_exit(void) | |
2798 | { | |
2799 | dm_unregister_target(&thin_target); | |
2800 | dm_unregister_target(&pool_target); | |
a24c2569 | 2801 | |
a24c2569 MS |
2802 | kmem_cache_destroy(_new_mapping_cache); |
2803 | kmem_cache_destroy(_endio_hook_cache); | |
991d9fa0 JT |
2804 | } |
2805 | ||
2806 | module_init(dm_thin_init); | |
2807 | module_exit(dm_thin_exit); | |
2808 | ||
7cab8bf1 | 2809 | MODULE_DESCRIPTION(DM_NAME " thin provisioning target"); |
991d9fa0 JT |
2810 | MODULE_AUTHOR("Joe Thornber <dm-devel@redhat.com>"); |
2811 | MODULE_LICENSE("GPL"); |