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7#include "dm-thin-metadata.h"
8#include "dm-bio-prison-v1.h"
9#include "dm.h"
10
11#include <linux/device-mapper.h>
12#include <linux/dm-io.h>
13#include <linux/dm-kcopyd.h>
14#include <linux/jiffies.h>
15#include <linux/log2.h>
16#include <linux/list.h>
17#include <linux/rculist.h>
18#include <linux/init.h>
19#include <linux/module.h>
20#include <linux/slab.h>
21#include <linux/vmalloc.h>
22#include <linux/sort.h>
23#include <linux/rbtree.h>
24
25#define DM_MSG_PREFIX "thin"
26
27
28
29
30#define ENDIO_HOOK_POOL_SIZE 1024
31#define MAPPING_POOL_SIZE 1024
32#define COMMIT_PERIOD HZ
33#define NO_SPACE_TIMEOUT_SECS 60
34
35static unsigned no_space_timeout_secs = NO_SPACE_TIMEOUT_SECS;
36
37DECLARE_DM_KCOPYD_THROTTLE_WITH_MODULE_PARM(snapshot_copy_throttle,
38 "A percentage of time allocated for copy on write");
39
40
41
42
43
44#define DATA_DEV_BLOCK_SIZE_MIN_SECTORS (64 * 1024 >> SECTOR_SHIFT)
45#define DATA_DEV_BLOCK_SIZE_MAX_SECTORS (1024 * 1024 * 1024 >> SECTOR_SHIFT)
46
47
48
49
50#define MAX_DEV_ID ((1 << 24) - 1)
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114
115enum lock_space {
116 VIRTUAL,
117 PHYSICAL
118};
119
120static void build_key(struct dm_thin_device *td, enum lock_space ls,
121 dm_block_t b, dm_block_t e, struct dm_cell_key *key)
122{
123 key->virtual = (ls == VIRTUAL);
124 key->dev = dm_thin_dev_id(td);
125 key->block_begin = b;
126 key->block_end = e;
127}
128
129static void build_data_key(struct dm_thin_device *td, dm_block_t b,
130 struct dm_cell_key *key)
131{
132 build_key(td, PHYSICAL, b, b + 1llu, key);
133}
134
135static void build_virtual_key(struct dm_thin_device *td, dm_block_t b,
136 struct dm_cell_key *key)
137{
138 build_key(td, VIRTUAL, b, b + 1llu, key);
139}
140
141
142
143#define THROTTLE_THRESHOLD (1 * HZ)
144
145struct throttle {
146 struct rw_semaphore lock;
147 unsigned long threshold;
148 bool throttle_applied;
149};
150
151static void throttle_init(struct throttle *t)
152{
153 init_rwsem(&t->lock);
154 t->throttle_applied = false;
155}
156
157static void throttle_work_start(struct throttle *t)
158{
159 t->threshold = jiffies + THROTTLE_THRESHOLD;
160}
161
162static void throttle_work_update(struct throttle *t)
163{
164 if (!t->throttle_applied && jiffies > t->threshold) {
165 down_write(&t->lock);
166 t->throttle_applied = true;
167 }
168}
169
170static void throttle_work_complete(struct throttle *t)
171{
172 if (t->throttle_applied) {
173 t->throttle_applied = false;
174 up_write(&t->lock);
175 }
176}
177
178static void throttle_lock(struct throttle *t)
179{
180 down_read(&t->lock);
181}
182
183static void throttle_unlock(struct throttle *t)
184{
185 up_read(&t->lock);
186}
187
188
189
190
191
192
193
194
195struct dm_thin_new_mapping;
196
197
198
199
200enum pool_mode {
201 PM_WRITE,
202 PM_OUT_OF_DATA_SPACE,
203 PM_READ_ONLY,
204 PM_FAIL,
205};
206
207struct pool_features {
208 enum pool_mode mode;
209
210 bool zero_new_blocks:1;
211 bool discard_enabled:1;
212 bool discard_passdown:1;
213 bool error_if_no_space:1;
214};
215
216struct thin_c;
217typedef void (*process_bio_fn)(struct thin_c *tc, struct bio *bio);
218typedef void (*process_cell_fn)(struct thin_c *tc, struct dm_bio_prison_cell *cell);
219typedef void (*process_mapping_fn)(struct dm_thin_new_mapping *m);
220
221#define CELL_SORT_ARRAY_SIZE 8192
222
223struct pool {
224 struct list_head list;
225 struct dm_target *ti;
226
227 struct mapped_device *pool_md;
228 struct block_device *md_dev;
229 struct dm_pool_metadata *pmd;
230
231 dm_block_t low_water_blocks;
232 uint32_t sectors_per_block;
233 int sectors_per_block_shift;
234
235 struct pool_features pf;
236 bool low_water_triggered:1;
237 bool suspended:1;
238 bool out_of_data_space:1;
239
240 struct dm_bio_prison *prison;
241 struct dm_kcopyd_client *copier;
242
243 struct workqueue_struct *wq;
244 struct throttle throttle;
245 struct work_struct worker;
246 struct delayed_work waker;
247 struct delayed_work no_space_timeout;
248
249 unsigned long last_commit_jiffies;
250 unsigned ref_count;
251
252 spinlock_t lock;
253 struct bio_list deferred_flush_bios;
254 struct list_head prepared_mappings;
255 struct list_head prepared_discards;
256 struct list_head prepared_discards_pt2;
257 struct list_head active_thins;
258
259 struct dm_deferred_set *shared_read_ds;
260 struct dm_deferred_set *all_io_ds;
261
262 struct dm_thin_new_mapping *next_mapping;
263 mempool_t *mapping_pool;
264
265 process_bio_fn process_bio;
266 process_bio_fn process_discard;
267
268 process_cell_fn process_cell;
269 process_cell_fn process_discard_cell;
270
271 process_mapping_fn process_prepared_mapping;
272 process_mapping_fn process_prepared_discard;
273 process_mapping_fn process_prepared_discard_pt2;
274
275 struct dm_bio_prison_cell **cell_sort_array;
276};
277
278static enum pool_mode get_pool_mode(struct pool *pool);
279static void metadata_operation_failed(struct pool *pool, const char *op, int r);
280
281
282
283
284struct pool_c {
285 struct dm_target *ti;
286 struct pool *pool;
287 struct dm_dev *data_dev;
288 struct dm_dev *metadata_dev;
289 struct dm_target_callbacks callbacks;
290
291 dm_block_t low_water_blocks;
292 struct pool_features requested_pf;
293 struct pool_features adjusted_pf;
294};
295
296
297
298
299struct thin_c {
300 struct list_head list;
301 struct dm_dev *pool_dev;
302 struct dm_dev *origin_dev;
303 sector_t origin_size;
304 dm_thin_id dev_id;
305
306 struct pool *pool;
307 struct dm_thin_device *td;
308 struct mapped_device *thin_md;
309
310 bool requeue_mode:1;
311 spinlock_t lock;
312 struct list_head deferred_cells;
313 struct bio_list deferred_bio_list;
314 struct bio_list retry_on_resume_list;
315 struct rb_root sort_bio_list;
316
317
318
319
320
321 atomic_t refcount;
322 struct completion can_destroy;
323};
324
325
326
327static bool block_size_is_power_of_two(struct pool *pool)
328{
329 return pool->sectors_per_block_shift >= 0;
330}
331
332static sector_t block_to_sectors(struct pool *pool, dm_block_t b)
333{
334 return block_size_is_power_of_two(pool) ?
335 (b << pool->sectors_per_block_shift) :
336 (b * pool->sectors_per_block);
337}
338
339
340
341struct discard_op {
342 struct thin_c *tc;
343 struct blk_plug plug;
344 struct bio *parent_bio;
345 struct bio *bio;
346};
347
348static void begin_discard(struct discard_op *op, struct thin_c *tc, struct bio *parent)
349{
350 BUG_ON(!parent);
351
352 op->tc = tc;
353 blk_start_plug(&op->plug);
354 op->parent_bio = parent;
355 op->bio = NULL;
356}
357
358static int issue_discard(struct discard_op *op, dm_block_t data_b, dm_block_t data_e)
359{
360 struct thin_c *tc = op->tc;
361 sector_t s = block_to_sectors(tc->pool, data_b);
362 sector_t len = block_to_sectors(tc->pool, data_e - data_b);
363
364 return __blkdev_issue_discard(tc->pool_dev->bdev, s, len,
365 GFP_NOWAIT, 0, &op->bio);
366}
367
368static void end_discard(struct discard_op *op, int r)
369{
370 if (op->bio) {
371
372
373
374
375 bio_chain(op->bio, op->parent_bio);
376 bio_set_op_attrs(op->bio, REQ_OP_DISCARD, 0);
377 submit_bio(op->bio);
378 }
379
380 blk_finish_plug(&op->plug);
381
382
383
384
385
386 if (r && !op->parent_bio->bi_status)
387 op->parent_bio->bi_status = errno_to_blk_status(r);
388 bio_endio(op->parent_bio);
389}
390
391
392
393
394
395
396
397static void wake_worker(struct pool *pool)
398{
399 queue_work(pool->wq, &pool->worker);
400}
401
402
403
404static int bio_detain(struct pool *pool, struct dm_cell_key *key, struct bio *bio,
405 struct dm_bio_prison_cell **cell_result)
406{
407 int r;
408 struct dm_bio_prison_cell *cell_prealloc;
409
410
411
412
413
414 cell_prealloc = dm_bio_prison_alloc_cell(pool->prison, GFP_NOIO);
415
416 r = dm_bio_detain(pool->prison, key, bio, cell_prealloc, cell_result);
417 if (r)
418
419
420
421
422 dm_bio_prison_free_cell(pool->prison, cell_prealloc);
423
424 return r;
425}
426
427static void cell_release(struct pool *pool,
428 struct dm_bio_prison_cell *cell,
429 struct bio_list *bios)
430{
431 dm_cell_release(pool->prison, cell, bios);
432 dm_bio_prison_free_cell(pool->prison, cell);
433}
434
435static void cell_visit_release(struct pool *pool,
436 void (*fn)(void *, struct dm_bio_prison_cell *),
437 void *context,
438 struct dm_bio_prison_cell *cell)
439{
440 dm_cell_visit_release(pool->prison, fn, context, cell);
441 dm_bio_prison_free_cell(pool->prison, cell);
442}
443
444static void cell_release_no_holder(struct pool *pool,
445 struct dm_bio_prison_cell *cell,
446 struct bio_list *bios)
447{
448 dm_cell_release_no_holder(pool->prison, cell, bios);
449 dm_bio_prison_free_cell(pool->prison, cell);
450}
451
452static void cell_error_with_code(struct pool *pool,
453 struct dm_bio_prison_cell *cell, blk_status_t error_code)
454{
455 dm_cell_error(pool->prison, cell, error_code);
456 dm_bio_prison_free_cell(pool->prison, cell);
457}
458
459static blk_status_t get_pool_io_error_code(struct pool *pool)
460{
461 return pool->out_of_data_space ? BLK_STS_NOSPC : BLK_STS_IOERR;
462}
463
464static void cell_error(struct pool *pool, struct dm_bio_prison_cell *cell)
465{
466 cell_error_with_code(pool, cell, get_pool_io_error_code(pool));
467}
468
469static void cell_success(struct pool *pool, struct dm_bio_prison_cell *cell)
470{
471 cell_error_with_code(pool, cell, 0);
472}
473
474static void cell_requeue(struct pool *pool, struct dm_bio_prison_cell *cell)
475{
476 cell_error_with_code(pool, cell, BLK_STS_DM_REQUEUE);
477}
478
479
480
481
482
483
484static struct dm_thin_pool_table {
485 struct mutex mutex;
486 struct list_head pools;
487} dm_thin_pool_table;
488
489static void pool_table_init(void)
490{
491 mutex_init(&dm_thin_pool_table.mutex);
492 INIT_LIST_HEAD(&dm_thin_pool_table.pools);
493}
494
495static void __pool_table_insert(struct pool *pool)
496{
497 BUG_ON(!mutex_is_locked(&dm_thin_pool_table.mutex));
498 list_add(&pool->list, &dm_thin_pool_table.pools);
499}
500
501static void __pool_table_remove(struct pool *pool)
502{
503 BUG_ON(!mutex_is_locked(&dm_thin_pool_table.mutex));
504 list_del(&pool->list);
505}
506
507static struct pool *__pool_table_lookup(struct mapped_device *md)
508{
509 struct pool *pool = NULL, *tmp;
510
511 BUG_ON(!mutex_is_locked(&dm_thin_pool_table.mutex));
512
513 list_for_each_entry(tmp, &dm_thin_pool_table.pools, list) {
514 if (tmp->pool_md == md) {
515 pool = tmp;
516 break;
517 }
518 }
519
520 return pool;
521}
522
523static struct pool *__pool_table_lookup_metadata_dev(struct block_device *md_dev)
524{
525 struct pool *pool = NULL, *tmp;
526
527 BUG_ON(!mutex_is_locked(&dm_thin_pool_table.mutex));
528
529 list_for_each_entry(tmp, &dm_thin_pool_table.pools, list) {
530 if (tmp->md_dev == md_dev) {
531 pool = tmp;
532 break;
533 }
534 }
535
536 return pool;
537}
538
539
540
541struct dm_thin_endio_hook {
542 struct thin_c *tc;
543 struct dm_deferred_entry *shared_read_entry;
544 struct dm_deferred_entry *all_io_entry;
545 struct dm_thin_new_mapping *overwrite_mapping;
546 struct rb_node rb_node;
547 struct dm_bio_prison_cell *cell;
548};
549
550static void __merge_bio_list(struct bio_list *bios, struct bio_list *master)
551{
552 bio_list_merge(bios, master);
553 bio_list_init(master);
554}
555
556static void error_bio_list(struct bio_list *bios, blk_status_t error)
557{
558 struct bio *bio;
559
560 while ((bio = bio_list_pop(bios))) {
561 bio->bi_status = error;
562 bio_endio(bio);
563 }
564}
565
566static void error_thin_bio_list(struct thin_c *tc, struct bio_list *master,
567 blk_status_t error)
568{
569 struct bio_list bios;
570 unsigned long flags;
571
572 bio_list_init(&bios);
573
574 spin_lock_irqsave(&tc->lock, flags);
575 __merge_bio_list(&bios, master);
576 spin_unlock_irqrestore(&tc->lock, flags);
577
578 error_bio_list(&bios, error);
579}
580
581static void requeue_deferred_cells(struct thin_c *tc)
582{
583 struct pool *pool = tc->pool;
584 unsigned long flags;
585 struct list_head cells;
586 struct dm_bio_prison_cell *cell, *tmp;
587
588 INIT_LIST_HEAD(&cells);
589
590 spin_lock_irqsave(&tc->lock, flags);
591 list_splice_init(&tc->deferred_cells, &cells);
592 spin_unlock_irqrestore(&tc->lock, flags);
593
594 list_for_each_entry_safe(cell, tmp, &cells, user_list)
595 cell_requeue(pool, cell);
596}
597
598static void requeue_io(struct thin_c *tc)
599{
600 struct bio_list bios;
601 unsigned long flags;
602
603 bio_list_init(&bios);
604
605 spin_lock_irqsave(&tc->lock, flags);
606 __merge_bio_list(&bios, &tc->deferred_bio_list);
607 __merge_bio_list(&bios, &tc->retry_on_resume_list);
608 spin_unlock_irqrestore(&tc->lock, flags);
609
610 error_bio_list(&bios, BLK_STS_DM_REQUEUE);
611 requeue_deferred_cells(tc);
612}
613
614static void error_retry_list_with_code(struct pool *pool, blk_status_t error)
615{
616 struct thin_c *tc;
617
618 rcu_read_lock();
619 list_for_each_entry_rcu(tc, &pool->active_thins, list)
620 error_thin_bio_list(tc, &tc->retry_on_resume_list, error);
621 rcu_read_unlock();
622}
623
624static void error_retry_list(struct pool *pool)
625{
626 error_retry_list_with_code(pool, get_pool_io_error_code(pool));
627}
628
629
630
631
632
633
634
635
636static dm_block_t get_bio_block(struct thin_c *tc, struct bio *bio)
637{
638 struct pool *pool = tc->pool;
639 sector_t block_nr = bio->bi_iter.bi_sector;
640
641 if (block_size_is_power_of_two(pool))
642 block_nr >>= pool->sectors_per_block_shift;
643 else
644 (void) sector_div(block_nr, pool->sectors_per_block);
645
646 return block_nr;
647}
648
649
650
651
652static void get_bio_block_range(struct thin_c *tc, struct bio *bio,
653 dm_block_t *begin, dm_block_t *end)
654{
655 struct pool *pool = tc->pool;
656 sector_t b = bio->bi_iter.bi_sector;
657 sector_t e = b + (bio->bi_iter.bi_size >> SECTOR_SHIFT);
658
659 b += pool->sectors_per_block - 1ull;
660
661 if (block_size_is_power_of_two(pool)) {
662 b >>= pool->sectors_per_block_shift;
663 e >>= pool->sectors_per_block_shift;
664 } else {
665 (void) sector_div(b, pool->sectors_per_block);
666 (void) sector_div(e, pool->sectors_per_block);
667 }
668
669 if (e < b)
670
671 e = b;
672
673 *begin = b;
674 *end = e;
675}
676
677static void remap(struct thin_c *tc, struct bio *bio, dm_block_t block)
678{
679 struct pool *pool = tc->pool;
680 sector_t bi_sector = bio->bi_iter.bi_sector;
681
682 bio_set_dev(bio, tc->pool_dev->bdev);
683 if (block_size_is_power_of_two(pool))
684 bio->bi_iter.bi_sector =
685 (block << pool->sectors_per_block_shift) |
686 (bi_sector & (pool->sectors_per_block - 1));
687 else
688 bio->bi_iter.bi_sector = (block * pool->sectors_per_block) +
689 sector_div(bi_sector, pool->sectors_per_block);
690}
691
692static void remap_to_origin(struct thin_c *tc, struct bio *bio)
693{
694 bio_set_dev(bio, tc->origin_dev->bdev);
695}
696
697static int bio_triggers_commit(struct thin_c *tc, struct bio *bio)
698{
699 return op_is_flush(bio->bi_opf) &&
700 dm_thin_changed_this_transaction(tc->td);
701}
702
703static void inc_all_io_entry(struct pool *pool, struct bio *bio)
704{
705 struct dm_thin_endio_hook *h;
706
707 if (bio_op(bio) == REQ_OP_DISCARD)
708 return;
709
710 h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook));
711 h->all_io_entry = dm_deferred_entry_inc(pool->all_io_ds);
712}
713
714static void issue(struct thin_c *tc, struct bio *bio)
715{
716 struct pool *pool = tc->pool;
717 unsigned long flags;
718
719 if (!bio_triggers_commit(tc, bio)) {
720 generic_make_request(bio);
721 return;
722 }
723
724
725
726
727
728
729 if (dm_thin_aborted_changes(tc->td)) {
730 bio_io_error(bio);
731 return;
732 }
733
734
735
736
737
738 spin_lock_irqsave(&pool->lock, flags);
739 bio_list_add(&pool->deferred_flush_bios, bio);
740 spin_unlock_irqrestore(&pool->lock, flags);
741}
742
743static void remap_to_origin_and_issue(struct thin_c *tc, struct bio *bio)
744{
745 remap_to_origin(tc, bio);
746 issue(tc, bio);
747}
748
749static void remap_and_issue(struct thin_c *tc, struct bio *bio,
750 dm_block_t block)
751{
752 remap(tc, bio, block);
753 issue(tc, bio);
754}
755
756
757
758
759
760
761struct dm_thin_new_mapping {
762 struct list_head list;
763
764 bool pass_discard:1;
765 bool maybe_shared:1;
766
767
768
769
770
771
772 atomic_t prepare_actions;
773
774 blk_status_t status;
775 struct thin_c *tc;
776 dm_block_t virt_begin, virt_end;
777 dm_block_t data_block;
778 struct dm_bio_prison_cell *cell;
779
780
781
782
783
784
785
786 struct bio *bio;
787 bio_end_io_t *saved_bi_end_io;
788};
789
790static void __complete_mapping_preparation(struct dm_thin_new_mapping *m)
791{
792 struct pool *pool = m->tc->pool;
793
794 if (atomic_dec_and_test(&m->prepare_actions)) {
795 list_add_tail(&m->list, &pool->prepared_mappings);
796 wake_worker(pool);
797 }
798}
799
800static void complete_mapping_preparation(struct dm_thin_new_mapping *m)
801{
802 unsigned long flags;
803 struct pool *pool = m->tc->pool;
804
805 spin_lock_irqsave(&pool->lock, flags);
806 __complete_mapping_preparation(m);
807 spin_unlock_irqrestore(&pool->lock, flags);
808}
809
810static void copy_complete(int read_err, unsigned long write_err, void *context)
811{
812 struct dm_thin_new_mapping *m = context;
813
814 m->status = read_err || write_err ? BLK_STS_IOERR : 0;
815 complete_mapping_preparation(m);
816}
817
818static void overwrite_endio(struct bio *bio)
819{
820 struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook));
821 struct dm_thin_new_mapping *m = h->overwrite_mapping;
822
823 bio->bi_end_io = m->saved_bi_end_io;
824
825 m->status = bio->bi_status;
826 complete_mapping_preparation(m);
827}
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843static void cell_defer_no_holder(struct thin_c *tc, struct dm_bio_prison_cell *cell)
844{
845 struct pool *pool = tc->pool;
846 unsigned long flags;
847
848 spin_lock_irqsave(&tc->lock, flags);
849 cell_release_no_holder(pool, cell, &tc->deferred_bio_list);
850 spin_unlock_irqrestore(&tc->lock, flags);
851
852 wake_worker(pool);
853}
854
855static void thin_defer_bio(struct thin_c *tc, struct bio *bio);
856
857struct remap_info {
858 struct thin_c *tc;
859 struct bio_list defer_bios;
860 struct bio_list issue_bios;
861};
862
863static void __inc_remap_and_issue_cell(void *context,
864 struct dm_bio_prison_cell *cell)
865{
866 struct remap_info *info = context;
867 struct bio *bio;
868
869 while ((bio = bio_list_pop(&cell->bios))) {
870 if (op_is_flush(bio->bi_opf) || bio_op(bio) == REQ_OP_DISCARD)
871 bio_list_add(&info->defer_bios, bio);
872 else {
873 inc_all_io_entry(info->tc->pool, bio);
874
875
876
877
878
879
880 bio_list_add(&info->issue_bios, bio);
881 }
882 }
883}
884
885static void inc_remap_and_issue_cell(struct thin_c *tc,
886 struct dm_bio_prison_cell *cell,
887 dm_block_t block)
888{
889 struct bio *bio;
890 struct remap_info info;
891
892 info.tc = tc;
893 bio_list_init(&info.defer_bios);
894 bio_list_init(&info.issue_bios);
895
896
897
898
899
900
901 cell_visit_release(tc->pool, __inc_remap_and_issue_cell,
902 &info, cell);
903
904 while ((bio = bio_list_pop(&info.defer_bios)))
905 thin_defer_bio(tc, bio);
906
907 while ((bio = bio_list_pop(&info.issue_bios)))
908 remap_and_issue(info.tc, bio, block);
909}
910
911static void process_prepared_mapping_fail(struct dm_thin_new_mapping *m)
912{
913 cell_error(m->tc->pool, m->cell);
914 list_del(&m->list);
915 mempool_free(m, m->tc->pool->mapping_pool);
916}
917
918static void process_prepared_mapping(struct dm_thin_new_mapping *m)
919{
920 struct thin_c *tc = m->tc;
921 struct pool *pool = tc->pool;
922 struct bio *bio = m->bio;
923 int r;
924
925 if (m->status) {
926 cell_error(pool, m->cell);
927 goto out;
928 }
929
930
931
932
933
934
935 r = dm_thin_insert_block(tc->td, m->virt_begin, m->data_block);
936 if (r) {
937 metadata_operation_failed(pool, "dm_thin_insert_block", r);
938 cell_error(pool, m->cell);
939 goto out;
940 }
941
942
943
944
945
946
947
948 if (bio) {
949 inc_remap_and_issue_cell(tc, m->cell, m->data_block);
950 bio_endio(bio);
951 } else {
952 inc_all_io_entry(tc->pool, m->cell->holder);
953 remap_and_issue(tc, m->cell->holder, m->data_block);
954 inc_remap_and_issue_cell(tc, m->cell, m->data_block);
955 }
956
957out:
958 list_del(&m->list);
959 mempool_free(m, pool->mapping_pool);
960}
961
962
963
964static void free_discard_mapping(struct dm_thin_new_mapping *m)
965{
966 struct thin_c *tc = m->tc;
967 if (m->cell)
968 cell_defer_no_holder(tc, m->cell);
969 mempool_free(m, tc->pool->mapping_pool);
970}
971
972static void process_prepared_discard_fail(struct dm_thin_new_mapping *m)
973{
974 bio_io_error(m->bio);
975 free_discard_mapping(m);
976}
977
978static void process_prepared_discard_success(struct dm_thin_new_mapping *m)
979{
980 bio_endio(m->bio);
981 free_discard_mapping(m);
982}
983
984static void process_prepared_discard_no_passdown(struct dm_thin_new_mapping *m)
985{
986 int r;
987 struct thin_c *tc = m->tc;
988
989 r = dm_thin_remove_range(tc->td, m->cell->key.block_begin, m->cell->key.block_end);
990 if (r) {
991 metadata_operation_failed(tc->pool, "dm_thin_remove_range", r);
992 bio_io_error(m->bio);
993 } else
994 bio_endio(m->bio);
995
996 cell_defer_no_holder(tc, m->cell);
997 mempool_free(m, tc->pool->mapping_pool);
998}
999
1000
1001
1002static void passdown_double_checking_shared_status(struct dm_thin_new_mapping *m,
1003 struct bio *discard_parent)
1004{
1005
1006
1007
1008
1009 int r = 0;
1010 bool used = true;
1011 struct thin_c *tc = m->tc;
1012 struct pool *pool = tc->pool;
1013 dm_block_t b = m->data_block, e, end = m->data_block + m->virt_end - m->virt_begin;
1014 struct discard_op op;
1015
1016 begin_discard(&op, tc, discard_parent);
1017 while (b != end) {
1018
1019 for (; b < end; b++) {
1020 r = dm_pool_block_is_used(pool->pmd, b, &used);
1021 if (r)
1022 goto out;
1023
1024 if (!used)
1025 break;
1026 }
1027
1028 if (b == end)
1029 break;
1030
1031
1032 for (e = b + 1; e != end; e++) {
1033 r = dm_pool_block_is_used(pool->pmd, e, &used);
1034 if (r)
1035 goto out;
1036
1037 if (used)
1038 break;
1039 }
1040
1041 r = issue_discard(&op, b, e);
1042 if (r)
1043 goto out;
1044
1045 b = e;
1046 }
1047out:
1048 end_discard(&op, r);
1049}
1050
1051static void queue_passdown_pt2(struct dm_thin_new_mapping *m)
1052{
1053 unsigned long flags;
1054 struct pool *pool = m->tc->pool;
1055
1056 spin_lock_irqsave(&pool->lock, flags);
1057 list_add_tail(&m->list, &pool->prepared_discards_pt2);
1058 spin_unlock_irqrestore(&pool->lock, flags);
1059 wake_worker(pool);
1060}
1061
1062static void passdown_endio(struct bio *bio)
1063{
1064
1065
1066
1067
1068 queue_passdown_pt2(bio->bi_private);
1069 bio_put(bio);
1070}
1071
1072static void process_prepared_discard_passdown_pt1(struct dm_thin_new_mapping *m)
1073{
1074 int r;
1075 struct thin_c *tc = m->tc;
1076 struct pool *pool = tc->pool;
1077 struct bio *discard_parent;
1078 dm_block_t data_end = m->data_block + (m->virt_end - m->virt_begin);
1079
1080
1081
1082
1083
1084
1085 r = dm_thin_remove_range(tc->td, m->virt_begin, m->virt_end);
1086 if (r) {
1087 metadata_operation_failed(pool, "dm_thin_remove_range", r);
1088 bio_io_error(m->bio);
1089 cell_defer_no_holder(tc, m->cell);
1090 mempool_free(m, pool->mapping_pool);
1091 return;
1092 }
1093
1094
1095
1096
1097
1098 r = dm_pool_inc_data_range(pool->pmd, m->data_block, data_end);
1099 if (r) {
1100 metadata_operation_failed(pool, "dm_pool_inc_data_range", r);
1101 bio_io_error(m->bio);
1102 cell_defer_no_holder(tc, m->cell);
1103 mempool_free(m, pool->mapping_pool);
1104 return;
1105 }
1106
1107 discard_parent = bio_alloc(GFP_NOIO, 1);
1108 if (!discard_parent) {
1109 DMWARN("%s: unable to allocate top level discard bio for passdown. Skipping passdown.",
1110 dm_device_name(tc->pool->pool_md));
1111 queue_passdown_pt2(m);
1112
1113 } else {
1114 discard_parent->bi_end_io = passdown_endio;
1115 discard_parent->bi_private = m;
1116
1117 if (m->maybe_shared)
1118 passdown_double_checking_shared_status(m, discard_parent);
1119 else {
1120 struct discard_op op;
1121
1122 begin_discard(&op, tc, discard_parent);
1123 r = issue_discard(&op, m->data_block, data_end);
1124 end_discard(&op, r);
1125 }
1126 }
1127}
1128
1129static void process_prepared_discard_passdown_pt2(struct dm_thin_new_mapping *m)
1130{
1131 int r;
1132 struct thin_c *tc = m->tc;
1133 struct pool *pool = tc->pool;
1134
1135
1136
1137
1138
1139 r = dm_pool_dec_data_range(pool->pmd, m->data_block,
1140 m->data_block + (m->virt_end - m->virt_begin));
1141 if (r) {
1142 metadata_operation_failed(pool, "dm_pool_dec_data_range", r);
1143 bio_io_error(m->bio);
1144 } else
1145 bio_endio(m->bio);
1146
1147 cell_defer_no_holder(tc, m->cell);
1148 mempool_free(m, pool->mapping_pool);
1149}
1150
1151static void process_prepared(struct pool *pool, struct list_head *head,
1152 process_mapping_fn *fn)
1153{
1154 unsigned long flags;
1155 struct list_head maps;
1156 struct dm_thin_new_mapping *m, *tmp;
1157
1158 INIT_LIST_HEAD(&maps);
1159 spin_lock_irqsave(&pool->lock, flags);
1160 list_splice_init(head, &maps);
1161 spin_unlock_irqrestore(&pool->lock, flags);
1162
1163 list_for_each_entry_safe(m, tmp, &maps, list)
1164 (*fn)(m);
1165}
1166
1167
1168
1169
1170static int io_overlaps_block(struct pool *pool, struct bio *bio)
1171{
1172 return bio->bi_iter.bi_size ==
1173 (pool->sectors_per_block << SECTOR_SHIFT);
1174}
1175
1176static int io_overwrites_block(struct pool *pool, struct bio *bio)
1177{
1178 return (bio_data_dir(bio) == WRITE) &&
1179 io_overlaps_block(pool, bio);
1180}
1181
1182static void save_and_set_endio(struct bio *bio, bio_end_io_t **save,
1183 bio_end_io_t *fn)
1184{
1185 *save = bio->bi_end_io;
1186 bio->bi_end_io = fn;
1187}
1188
1189static int ensure_next_mapping(struct pool *pool)
1190{
1191 if (pool->next_mapping)
1192 return 0;
1193
1194 pool->next_mapping = mempool_alloc(pool->mapping_pool, GFP_ATOMIC);
1195
1196 return pool->next_mapping ? 0 : -ENOMEM;
1197}
1198
1199static struct dm_thin_new_mapping *get_next_mapping(struct pool *pool)
1200{
1201 struct dm_thin_new_mapping *m = pool->next_mapping;
1202
1203 BUG_ON(!pool->next_mapping);
1204
1205 memset(m, 0, sizeof(struct dm_thin_new_mapping));
1206 INIT_LIST_HEAD(&m->list);
1207 m->bio = NULL;
1208
1209 pool->next_mapping = NULL;
1210
1211 return m;
1212}
1213
1214static void ll_zero(struct thin_c *tc, struct dm_thin_new_mapping *m,
1215 sector_t begin, sector_t end)
1216{
1217 int r;
1218 struct dm_io_region to;
1219
1220 to.bdev = tc->pool_dev->bdev;
1221 to.sector = begin;
1222 to.count = end - begin;
1223
1224 r = dm_kcopyd_zero(tc->pool->copier, 1, &to, 0, copy_complete, m);
1225 if (r < 0) {
1226 DMERR_LIMIT("dm_kcopyd_zero() failed");
1227 copy_complete(1, 1, m);
1228 }
1229}
1230
1231static void remap_and_issue_overwrite(struct thin_c *tc, struct bio *bio,
1232 dm_block_t data_begin,
1233 struct dm_thin_new_mapping *m)
1234{
1235 struct pool *pool = tc->pool;
1236 struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook));
1237
1238 h->overwrite_mapping = m;
1239 m->bio = bio;
1240 save_and_set_endio(bio, &m->saved_bi_end_io, overwrite_endio);
1241 inc_all_io_entry(pool, bio);
1242 remap_and_issue(tc, bio, data_begin);
1243}
1244
1245
1246
1247
1248static void schedule_copy(struct thin_c *tc, dm_block_t virt_block,
1249 struct dm_dev *origin, dm_block_t data_origin,
1250 dm_block_t data_dest,
1251 struct dm_bio_prison_cell *cell, struct bio *bio,
1252 sector_t len)
1253{
1254 int r;
1255 struct pool *pool = tc->pool;
1256 struct dm_thin_new_mapping *m = get_next_mapping(pool);
1257
1258 m->tc = tc;
1259 m->virt_begin = virt_block;
1260 m->virt_end = virt_block + 1u;
1261 m->data_block = data_dest;
1262 m->cell = cell;
1263
1264
1265
1266
1267
1268
1269 atomic_set(&m->prepare_actions, 3);
1270
1271 if (!dm_deferred_set_add_work(pool->shared_read_ds, &m->list))
1272 complete_mapping_preparation(m);
1273
1274
1275
1276
1277
1278
1279
1280 if (io_overwrites_block(pool, bio))
1281 remap_and_issue_overwrite(tc, bio, data_dest, m);
1282 else {
1283 struct dm_io_region from, to;
1284
1285 from.bdev = origin->bdev;
1286 from.sector = data_origin * pool->sectors_per_block;
1287 from.count = len;
1288
1289 to.bdev = tc->pool_dev->bdev;
1290 to.sector = data_dest * pool->sectors_per_block;
1291 to.count = len;
1292
1293 r = dm_kcopyd_copy(pool->copier, &from, 1, &to,
1294 0, copy_complete, m);
1295 if (r < 0) {
1296 DMERR_LIMIT("dm_kcopyd_copy() failed");
1297 copy_complete(1, 1, m);
1298
1299
1300
1301
1302
1303
1304
1305 }
1306
1307
1308
1309
1310 if (len < pool->sectors_per_block && pool->pf.zero_new_blocks) {
1311 atomic_inc(&m->prepare_actions);
1312 ll_zero(tc, m,
1313 data_dest * pool->sectors_per_block + len,
1314 (data_dest + 1) * pool->sectors_per_block);
1315 }
1316 }
1317
1318 complete_mapping_preparation(m);
1319}
1320
1321static void schedule_internal_copy(struct thin_c *tc, dm_block_t virt_block,
1322 dm_block_t data_origin, dm_block_t data_dest,
1323 struct dm_bio_prison_cell *cell, struct bio *bio)
1324{
1325 schedule_copy(tc, virt_block, tc->pool_dev,
1326 data_origin, data_dest, cell, bio,
1327 tc->pool->sectors_per_block);
1328}
1329
1330static void schedule_zero(struct thin_c *tc, dm_block_t virt_block,
1331 dm_block_t data_block, struct dm_bio_prison_cell *cell,
1332 struct bio *bio)
1333{
1334 struct pool *pool = tc->pool;
1335 struct dm_thin_new_mapping *m = get_next_mapping(pool);
1336
1337 atomic_set(&m->prepare_actions, 1);
1338 m->tc = tc;
1339 m->virt_begin = virt_block;
1340 m->virt_end = virt_block + 1u;
1341 m->data_block = data_block;
1342 m->cell = cell;
1343
1344
1345
1346
1347
1348
1349 if (pool->pf.zero_new_blocks) {
1350 if (io_overwrites_block(pool, bio))
1351 remap_and_issue_overwrite(tc, bio, data_block, m);
1352 else
1353 ll_zero(tc, m, data_block * pool->sectors_per_block,
1354 (data_block + 1) * pool->sectors_per_block);
1355 } else
1356 process_prepared_mapping(m);
1357}
1358
1359static void schedule_external_copy(struct thin_c *tc, dm_block_t virt_block,
1360 dm_block_t data_dest,
1361 struct dm_bio_prison_cell *cell, struct bio *bio)
1362{
1363 struct pool *pool = tc->pool;
1364 sector_t virt_block_begin = virt_block * pool->sectors_per_block;
1365 sector_t virt_block_end = (virt_block + 1) * pool->sectors_per_block;
1366
1367 if (virt_block_end <= tc->origin_size)
1368 schedule_copy(tc, virt_block, tc->origin_dev,
1369 virt_block, data_dest, cell, bio,
1370 pool->sectors_per_block);
1371
1372 else if (virt_block_begin < tc->origin_size)
1373 schedule_copy(tc, virt_block, tc->origin_dev,
1374 virt_block, data_dest, cell, bio,
1375 tc->origin_size - virt_block_begin);
1376
1377 else
1378 schedule_zero(tc, virt_block, data_dest, cell, bio);
1379}
1380
1381static void set_pool_mode(struct pool *pool, enum pool_mode new_mode);
1382
1383static void check_for_space(struct pool *pool)
1384{
1385 int r;
1386 dm_block_t nr_free;
1387
1388 if (get_pool_mode(pool) != PM_OUT_OF_DATA_SPACE)
1389 return;
1390
1391 r = dm_pool_get_free_block_count(pool->pmd, &nr_free);
1392 if (r)
1393 return;
1394
1395 if (nr_free)
1396 set_pool_mode(pool, PM_WRITE);
1397}
1398
1399
1400
1401
1402
1403static int commit(struct pool *pool)
1404{
1405 int r;
1406
1407 if (get_pool_mode(pool) >= PM_READ_ONLY)
1408 return -EINVAL;
1409
1410 r = dm_pool_commit_metadata(pool->pmd);
1411 if (r)
1412 metadata_operation_failed(pool, "dm_pool_commit_metadata", r);
1413 else
1414 check_for_space(pool);
1415
1416 return r;
1417}
1418
1419static void check_low_water_mark(struct pool *pool, dm_block_t free_blocks)
1420{
1421 unsigned long flags;
1422
1423 if (free_blocks <= pool->low_water_blocks && !pool->low_water_triggered) {
1424 DMWARN("%s: reached low water mark for data device: sending event.",
1425 dm_device_name(pool->pool_md));
1426 spin_lock_irqsave(&pool->lock, flags);
1427 pool->low_water_triggered = true;
1428 spin_unlock_irqrestore(&pool->lock, flags);
1429 dm_table_event(pool->ti->table);
1430 }
1431}
1432
1433static int alloc_data_block(struct thin_c *tc, dm_block_t *result)
1434{
1435 int r;
1436 dm_block_t free_blocks;
1437 struct pool *pool = tc->pool;
1438
1439 if (WARN_ON(get_pool_mode(pool) != PM_WRITE))
1440 return -EINVAL;
1441
1442 r = dm_pool_get_free_block_count(pool->pmd, &free_blocks);
1443 if (r) {
1444 metadata_operation_failed(pool, "dm_pool_get_free_block_count", r);
1445 return r;
1446 }
1447
1448 check_low_water_mark(pool, free_blocks);
1449
1450 if (!free_blocks) {
1451
1452
1453
1454
1455 r = commit(pool);
1456 if (r)
1457 return r;
1458
1459 r = dm_pool_get_free_block_count(pool->pmd, &free_blocks);
1460 if (r) {
1461 metadata_operation_failed(pool, "dm_pool_get_free_block_count", r);
1462 return r;
1463 }
1464
1465 if (!free_blocks) {
1466 set_pool_mode(pool, PM_OUT_OF_DATA_SPACE);
1467 return -ENOSPC;
1468 }
1469 }
1470
1471 r = dm_pool_alloc_data_block(pool->pmd, result);
1472 if (r) {
1473 metadata_operation_failed(pool, "dm_pool_alloc_data_block", r);
1474 return r;
1475 }
1476
1477 return 0;
1478}
1479
1480
1481
1482
1483
1484static void retry_on_resume(struct bio *bio)
1485{
1486 struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook));
1487 struct thin_c *tc = h->tc;
1488 unsigned long flags;
1489
1490 spin_lock_irqsave(&tc->lock, flags);
1491 bio_list_add(&tc->retry_on_resume_list, bio);
1492 spin_unlock_irqrestore(&tc->lock, flags);
1493}
1494
1495static blk_status_t should_error_unserviceable_bio(struct pool *pool)
1496{
1497 enum pool_mode m = get_pool_mode(pool);
1498
1499 switch (m) {
1500 case PM_WRITE:
1501
1502 DMERR_LIMIT("bio unserviceable, yet pool is in PM_WRITE mode");
1503 return BLK_STS_IOERR;
1504
1505 case PM_OUT_OF_DATA_SPACE:
1506 return pool->pf.error_if_no_space ? BLK_STS_NOSPC : 0;
1507
1508 case PM_READ_ONLY:
1509 case PM_FAIL:
1510 return BLK_STS_IOERR;
1511 default:
1512
1513 DMERR_LIMIT("bio unserviceable, yet pool has an unknown mode");
1514 return BLK_STS_IOERR;
1515 }
1516}
1517
1518static void handle_unserviceable_bio(struct pool *pool, struct bio *bio)
1519{
1520 blk_status_t error = should_error_unserviceable_bio(pool);
1521
1522 if (error) {
1523 bio->bi_status = error;
1524 bio_endio(bio);
1525 } else
1526 retry_on_resume(bio);
1527}
1528
1529static void retry_bios_on_resume(struct pool *pool, struct dm_bio_prison_cell *cell)
1530{
1531 struct bio *bio;
1532 struct bio_list bios;
1533 blk_status_t error;
1534
1535 error = should_error_unserviceable_bio(pool);
1536 if (error) {
1537 cell_error_with_code(pool, cell, error);
1538 return;
1539 }
1540
1541 bio_list_init(&bios);
1542 cell_release(pool, cell, &bios);
1543
1544 while ((bio = bio_list_pop(&bios)))
1545 retry_on_resume(bio);
1546}
1547
1548static void process_discard_cell_no_passdown(struct thin_c *tc,
1549 struct dm_bio_prison_cell *virt_cell)
1550{
1551 struct pool *pool = tc->pool;
1552 struct dm_thin_new_mapping *m = get_next_mapping(pool);
1553
1554
1555
1556
1557
1558 m->tc = tc;
1559 m->virt_begin = virt_cell->key.block_begin;
1560 m->virt_end = virt_cell->key.block_end;
1561 m->cell = virt_cell;
1562 m->bio = virt_cell->holder;
1563
1564 if (!dm_deferred_set_add_work(pool->all_io_ds, &m->list))
1565 pool->process_prepared_discard(m);
1566}
1567
1568static void break_up_discard_bio(struct thin_c *tc, dm_block_t begin, dm_block_t end,
1569 struct bio *bio)
1570{
1571 struct pool *pool = tc->pool;
1572
1573 int r;
1574 bool maybe_shared;
1575 struct dm_cell_key data_key;
1576 struct dm_bio_prison_cell *data_cell;
1577 struct dm_thin_new_mapping *m;
1578 dm_block_t virt_begin, virt_end, data_begin;
1579
1580 while (begin != end) {
1581 r = ensure_next_mapping(pool);
1582 if (r)
1583
1584 return;
1585
1586 r = dm_thin_find_mapped_range(tc->td, begin, end, &virt_begin, &virt_end,
1587 &data_begin, &maybe_shared);
1588 if (r)
1589
1590
1591
1592
1593 break;
1594
1595 build_key(tc->td, PHYSICAL, data_begin, data_begin + (virt_end - virt_begin), &data_key);
1596 if (bio_detain(tc->pool, &data_key, NULL, &data_cell)) {
1597
1598 begin = virt_end;
1599 continue;
1600 }
1601
1602
1603
1604
1605
1606 m = get_next_mapping(pool);
1607 m->tc = tc;
1608 m->maybe_shared = maybe_shared;
1609 m->virt_begin = virt_begin;
1610 m->virt_end = virt_end;
1611 m->data_block = data_begin;
1612 m->cell = data_cell;
1613 m->bio = bio;
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623 bio_inc_remaining(bio);
1624 if (!dm_deferred_set_add_work(pool->all_io_ds, &m->list))
1625 pool->process_prepared_discard(m);
1626
1627 begin = virt_end;
1628 }
1629}
1630
1631static void process_discard_cell_passdown(struct thin_c *tc, struct dm_bio_prison_cell *virt_cell)
1632{
1633 struct bio *bio = virt_cell->holder;
1634 struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook));
1635
1636
1637
1638
1639
1640
1641 h->cell = virt_cell;
1642 break_up_discard_bio(tc, virt_cell->key.block_begin, virt_cell->key.block_end, bio);
1643
1644
1645
1646
1647
1648
1649 bio_endio(bio);
1650}
1651
1652static void process_discard_bio(struct thin_c *tc, struct bio *bio)
1653{
1654 dm_block_t begin, end;
1655 struct dm_cell_key virt_key;
1656 struct dm_bio_prison_cell *virt_cell;
1657
1658 get_bio_block_range(tc, bio, &begin, &end);
1659 if (begin == end) {
1660
1661
1662
1663 bio_endio(bio);
1664 return;
1665 }
1666
1667 build_key(tc->td, VIRTUAL, begin, end, &virt_key);
1668 if (bio_detain(tc->pool, &virt_key, bio, &virt_cell))
1669
1670
1671
1672
1673
1674
1675
1676 return;
1677
1678 tc->pool->process_discard_cell(tc, virt_cell);
1679}
1680
1681static void break_sharing(struct thin_c *tc, struct bio *bio, dm_block_t block,
1682 struct dm_cell_key *key,
1683 struct dm_thin_lookup_result *lookup_result,
1684 struct dm_bio_prison_cell *cell)
1685{
1686 int r;
1687 dm_block_t data_block;
1688 struct pool *pool = tc->pool;
1689
1690 r = alloc_data_block(tc, &data_block);
1691 switch (r) {
1692 case 0:
1693 schedule_internal_copy(tc, block, lookup_result->block,
1694 data_block, cell, bio);
1695 break;
1696
1697 case -ENOSPC:
1698 retry_bios_on_resume(pool, cell);
1699 break;
1700
1701 default:
1702 DMERR_LIMIT("%s: alloc_data_block() failed: error = %d",
1703 __func__, r);
1704 cell_error(pool, cell);
1705 break;
1706 }
1707}
1708
1709static void __remap_and_issue_shared_cell(void *context,
1710 struct dm_bio_prison_cell *cell)
1711{
1712 struct remap_info *info = context;
1713 struct bio *bio;
1714
1715 while ((bio = bio_list_pop(&cell->bios))) {
1716 if (bio_data_dir(bio) == WRITE || op_is_flush(bio->bi_opf) ||
1717 bio_op(bio) == REQ_OP_DISCARD)
1718 bio_list_add(&info->defer_bios, bio);
1719 else {
1720 struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook));;
1721
1722 h->shared_read_entry = dm_deferred_entry_inc(info->tc->pool->shared_read_ds);
1723 inc_all_io_entry(info->tc->pool, bio);
1724 bio_list_add(&info->issue_bios, bio);
1725 }
1726 }
1727}
1728
1729static void remap_and_issue_shared_cell(struct thin_c *tc,
1730 struct dm_bio_prison_cell *cell,
1731 dm_block_t block)
1732{
1733 struct bio *bio;
1734 struct remap_info info;
1735
1736 info.tc = tc;
1737 bio_list_init(&info.defer_bios);
1738 bio_list_init(&info.issue_bios);
1739
1740 cell_visit_release(tc->pool, __remap_and_issue_shared_cell,
1741 &info, cell);
1742
1743 while ((bio = bio_list_pop(&info.defer_bios)))
1744 thin_defer_bio(tc, bio);
1745
1746 while ((bio = bio_list_pop(&info.issue_bios)))
1747 remap_and_issue(tc, bio, block);
1748}
1749
1750static void process_shared_bio(struct thin_c *tc, struct bio *bio,
1751 dm_block_t block,
1752 struct dm_thin_lookup_result *lookup_result,
1753 struct dm_bio_prison_cell *virt_cell)
1754{
1755 struct dm_bio_prison_cell *data_cell;
1756 struct pool *pool = tc->pool;
1757 struct dm_cell_key key;
1758
1759
1760
1761
1762
1763 build_data_key(tc->td, lookup_result->block, &key);
1764 if (bio_detain(pool, &key, bio, &data_cell)) {
1765 cell_defer_no_holder(tc, virt_cell);
1766 return;
1767 }
1768
1769 if (bio_data_dir(bio) == WRITE && bio->bi_iter.bi_size) {
1770 break_sharing(tc, bio, block, &key, lookup_result, data_cell);
1771 cell_defer_no_holder(tc, virt_cell);
1772 } else {
1773 struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook));
1774
1775 h->shared_read_entry = dm_deferred_entry_inc(pool->shared_read_ds);
1776 inc_all_io_entry(pool, bio);
1777 remap_and_issue(tc, bio, lookup_result->block);
1778
1779 remap_and_issue_shared_cell(tc, data_cell, lookup_result->block);
1780 remap_and_issue_shared_cell(tc, virt_cell, lookup_result->block);
1781 }
1782}
1783
1784static void provision_block(struct thin_c *tc, struct bio *bio, dm_block_t block,
1785 struct dm_bio_prison_cell *cell)
1786{
1787 int r;
1788 dm_block_t data_block;
1789 struct pool *pool = tc->pool;
1790
1791
1792
1793
1794 if (!bio->bi_iter.bi_size) {
1795 inc_all_io_entry(pool, bio);
1796 cell_defer_no_holder(tc, cell);
1797
1798 remap_and_issue(tc, bio, 0);
1799 return;
1800 }
1801
1802
1803
1804
1805 if (bio_data_dir(bio) == READ) {
1806 zero_fill_bio(bio);
1807 cell_defer_no_holder(tc, cell);
1808 bio_endio(bio);
1809 return;
1810 }
1811
1812 r = alloc_data_block(tc, &data_block);
1813 switch (r) {
1814 case 0:
1815 if (tc->origin_dev)
1816 schedule_external_copy(tc, block, data_block, cell, bio);
1817 else
1818 schedule_zero(tc, block, data_block, cell, bio);
1819 break;
1820
1821 case -ENOSPC:
1822 retry_bios_on_resume(pool, cell);
1823 break;
1824
1825 default:
1826 DMERR_LIMIT("%s: alloc_data_block() failed: error = %d",
1827 __func__, r);
1828 cell_error(pool, cell);
1829 break;
1830 }
1831}
1832
1833static void process_cell(struct thin_c *tc, struct dm_bio_prison_cell *cell)
1834{
1835 int r;
1836 struct pool *pool = tc->pool;
1837 struct bio *bio = cell->holder;
1838 dm_block_t block = get_bio_block(tc, bio);
1839 struct dm_thin_lookup_result lookup_result;
1840
1841 if (tc->requeue_mode) {
1842 cell_requeue(pool, cell);
1843 return;
1844 }
1845
1846 r = dm_thin_find_block(tc->td, block, 1, &lookup_result);
1847 switch (r) {
1848 case 0:
1849 if (lookup_result.shared)
1850 process_shared_bio(tc, bio, block, &lookup_result, cell);
1851 else {
1852 inc_all_io_entry(pool, bio);
1853 remap_and_issue(tc, bio, lookup_result.block);
1854 inc_remap_and_issue_cell(tc, cell, lookup_result.block);
1855 }
1856 break;
1857
1858 case -ENODATA:
1859 if (bio_data_dir(bio) == READ && tc->origin_dev) {
1860 inc_all_io_entry(pool, bio);
1861 cell_defer_no_holder(tc, cell);
1862
1863 if (bio_end_sector(bio) <= tc->origin_size)
1864 remap_to_origin_and_issue(tc, bio);
1865
1866 else if (bio->bi_iter.bi_sector < tc->origin_size) {
1867 zero_fill_bio(bio);
1868 bio->bi_iter.bi_size = (tc->origin_size - bio->bi_iter.bi_sector) << SECTOR_SHIFT;
1869 remap_to_origin_and_issue(tc, bio);
1870
1871 } else {
1872 zero_fill_bio(bio);
1873 bio_endio(bio);
1874 }
1875 } else
1876 provision_block(tc, bio, block, cell);
1877 break;
1878
1879 default:
1880 DMERR_LIMIT("%s: dm_thin_find_block() failed: error = %d",
1881 __func__, r);
1882 cell_defer_no_holder(tc, cell);
1883 bio_io_error(bio);
1884 break;
1885 }
1886}
1887
1888static void process_bio(struct thin_c *tc, struct bio *bio)
1889{
1890 struct pool *pool = tc->pool;
1891 dm_block_t block = get_bio_block(tc, bio);
1892 struct dm_bio_prison_cell *cell;
1893 struct dm_cell_key key;
1894
1895
1896
1897
1898
1899 build_virtual_key(tc->td, block, &key);
1900 if (bio_detain(pool, &key, bio, &cell))
1901 return;
1902
1903 process_cell(tc, cell);
1904}
1905
1906static void __process_bio_read_only(struct thin_c *tc, struct bio *bio,
1907 struct dm_bio_prison_cell *cell)
1908{
1909 int r;
1910 int rw = bio_data_dir(bio);
1911 dm_block_t block = get_bio_block(tc, bio);
1912 struct dm_thin_lookup_result lookup_result;
1913
1914 r = dm_thin_find_block(tc->td, block, 1, &lookup_result);
1915 switch (r) {
1916 case 0:
1917 if (lookup_result.shared && (rw == WRITE) && bio->bi_iter.bi_size) {
1918 handle_unserviceable_bio(tc->pool, bio);
1919 if (cell)
1920 cell_defer_no_holder(tc, cell);
1921 } else {
1922 inc_all_io_entry(tc->pool, bio);
1923 remap_and_issue(tc, bio, lookup_result.block);
1924 if (cell)
1925 inc_remap_and_issue_cell(tc, cell, lookup_result.block);
1926 }
1927 break;
1928
1929 case -ENODATA:
1930 if (cell)
1931 cell_defer_no_holder(tc, cell);
1932 if (rw != READ) {
1933 handle_unserviceable_bio(tc->pool, bio);
1934 break;
1935 }
1936
1937 if (tc->origin_dev) {
1938 inc_all_io_entry(tc->pool, bio);
1939 remap_to_origin_and_issue(tc, bio);
1940 break;
1941 }
1942
1943 zero_fill_bio(bio);
1944 bio_endio(bio);
1945 break;
1946
1947 default:
1948 DMERR_LIMIT("%s: dm_thin_find_block() failed: error = %d",
1949 __func__, r);
1950 if (cell)
1951 cell_defer_no_holder(tc, cell);
1952 bio_io_error(bio);
1953 break;
1954 }
1955}
1956
1957static void process_bio_read_only(struct thin_c *tc, struct bio *bio)
1958{
1959 __process_bio_read_only(tc, bio, NULL);
1960}
1961
1962static void process_cell_read_only(struct thin_c *tc, struct dm_bio_prison_cell *cell)
1963{
1964 __process_bio_read_only(tc, cell->holder, cell);
1965}
1966
1967static void process_bio_success(struct thin_c *tc, struct bio *bio)
1968{
1969 bio_endio(bio);
1970}
1971
1972static void process_bio_fail(struct thin_c *tc, struct bio *bio)
1973{
1974 bio_io_error(bio);
1975}
1976
1977static void process_cell_success(struct thin_c *tc, struct dm_bio_prison_cell *cell)
1978{
1979 cell_success(tc->pool, cell);
1980}
1981
1982static void process_cell_fail(struct thin_c *tc, struct dm_bio_prison_cell *cell)
1983{
1984 cell_error(tc->pool, cell);
1985}
1986
1987
1988
1989
1990
1991static int need_commit_due_to_time(struct pool *pool)
1992{
1993 return !time_in_range(jiffies, pool->last_commit_jiffies,
1994 pool->last_commit_jiffies + COMMIT_PERIOD);
1995}
1996
1997#define thin_pbd(node) rb_entry((node), struct dm_thin_endio_hook, rb_node)
1998#define thin_bio(pbd) dm_bio_from_per_bio_data((pbd), sizeof(struct dm_thin_endio_hook))
1999
2000static void __thin_bio_rb_add(struct thin_c *tc, struct bio *bio)
2001{
2002 struct rb_node **rbp, *parent;
2003 struct dm_thin_endio_hook *pbd;
2004 sector_t bi_sector = bio->bi_iter.bi_sector;
2005
2006 rbp = &tc->sort_bio_list.rb_node;
2007 parent = NULL;
2008 while (*rbp) {
2009 parent = *rbp;
2010 pbd = thin_pbd(parent);
2011
2012 if (bi_sector < thin_bio(pbd)->bi_iter.bi_sector)
2013 rbp = &(*rbp)->rb_left;
2014 else
2015 rbp = &(*rbp)->rb_right;
2016 }
2017
2018 pbd = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook));
2019 rb_link_node(&pbd->rb_node, parent, rbp);
2020 rb_insert_color(&pbd->rb_node, &tc->sort_bio_list);
2021}
2022
2023static void __extract_sorted_bios(struct thin_c *tc)
2024{
2025 struct rb_node *node;
2026 struct dm_thin_endio_hook *pbd;
2027 struct bio *bio;
2028
2029 for (node = rb_first(&tc->sort_bio_list); node; node = rb_next(node)) {
2030 pbd = thin_pbd(node);
2031 bio = thin_bio(pbd);
2032
2033 bio_list_add(&tc->deferred_bio_list, bio);
2034 rb_erase(&pbd->rb_node, &tc->sort_bio_list);
2035 }
2036
2037 WARN_ON(!RB_EMPTY_ROOT(&tc->sort_bio_list));
2038}
2039
2040static void __sort_thin_deferred_bios(struct thin_c *tc)
2041{
2042 struct bio *bio;
2043 struct bio_list bios;
2044
2045 bio_list_init(&bios);
2046 bio_list_merge(&bios, &tc->deferred_bio_list);
2047 bio_list_init(&tc->deferred_bio_list);
2048
2049
2050 while ((bio = bio_list_pop(&bios)))
2051 __thin_bio_rb_add(tc, bio);
2052
2053
2054
2055
2056
2057
2058 __extract_sorted_bios(tc);
2059}
2060
2061static void process_thin_deferred_bios(struct thin_c *tc)
2062{
2063 struct pool *pool = tc->pool;
2064 unsigned long flags;
2065 struct bio *bio;
2066 struct bio_list bios;
2067 struct blk_plug plug;
2068 unsigned count = 0;
2069
2070 if (tc->requeue_mode) {
2071 error_thin_bio_list(tc, &tc->deferred_bio_list,
2072 BLK_STS_DM_REQUEUE);
2073 return;
2074 }
2075
2076 bio_list_init(&bios);
2077
2078 spin_lock_irqsave(&tc->lock, flags);
2079
2080 if (bio_list_empty(&tc->deferred_bio_list)) {
2081 spin_unlock_irqrestore(&tc->lock, flags);
2082 return;
2083 }
2084
2085 __sort_thin_deferred_bios(tc);
2086
2087 bio_list_merge(&bios, &tc->deferred_bio_list);
2088 bio_list_init(&tc->deferred_bio_list);
2089
2090 spin_unlock_irqrestore(&tc->lock, flags);
2091
2092 blk_start_plug(&plug);
2093 while ((bio = bio_list_pop(&bios))) {
2094
2095
2096
2097
2098
2099 if (ensure_next_mapping(pool)) {
2100 spin_lock_irqsave(&tc->lock, flags);
2101 bio_list_add(&tc->deferred_bio_list, bio);
2102 bio_list_merge(&tc->deferred_bio_list, &bios);
2103 spin_unlock_irqrestore(&tc->lock, flags);
2104 break;
2105 }
2106
2107 if (bio_op(bio) == REQ_OP_DISCARD)
2108 pool->process_discard(tc, bio);
2109 else
2110 pool->process_bio(tc, bio);
2111
2112 if ((count++ & 127) == 0) {
2113 throttle_work_update(&pool->throttle);
2114 dm_pool_issue_prefetches(pool->pmd);
2115 }
2116 }
2117 blk_finish_plug(&plug);
2118}
2119
2120static int cmp_cells(const void *lhs, const void *rhs)
2121{
2122 struct dm_bio_prison_cell *lhs_cell = *((struct dm_bio_prison_cell **) lhs);
2123 struct dm_bio_prison_cell *rhs_cell = *((struct dm_bio_prison_cell **) rhs);
2124
2125 BUG_ON(!lhs_cell->holder);
2126 BUG_ON(!rhs_cell->holder);
2127
2128 if (lhs_cell->holder->bi_iter.bi_sector < rhs_cell->holder->bi_iter.bi_sector)
2129 return -1;
2130
2131 if (lhs_cell->holder->bi_iter.bi_sector > rhs_cell->holder->bi_iter.bi_sector)
2132 return 1;
2133
2134 return 0;
2135}
2136
2137static unsigned sort_cells(struct pool *pool, struct list_head *cells)
2138{
2139 unsigned count = 0;
2140 struct dm_bio_prison_cell *cell, *tmp;
2141
2142 list_for_each_entry_safe(cell, tmp, cells, user_list) {
2143 if (count >= CELL_SORT_ARRAY_SIZE)
2144 break;
2145
2146 pool->cell_sort_array[count++] = cell;
2147 list_del(&cell->user_list);
2148 }
2149
2150 sort(pool->cell_sort_array, count, sizeof(cell), cmp_cells, NULL);
2151
2152 return count;
2153}
2154
2155static void process_thin_deferred_cells(struct thin_c *tc)
2156{
2157 struct pool *pool = tc->pool;
2158 unsigned long flags;
2159 struct list_head cells;
2160 struct dm_bio_prison_cell *cell;
2161 unsigned i, j, count;
2162
2163 INIT_LIST_HEAD(&cells);
2164
2165 spin_lock_irqsave(&tc->lock, flags);
2166 list_splice_init(&tc->deferred_cells, &cells);
2167 spin_unlock_irqrestore(&tc->lock, flags);
2168
2169 if (list_empty(&cells))
2170 return;
2171
2172 do {
2173 count = sort_cells(tc->pool, &cells);
2174
2175 for (i = 0; i < count; i++) {
2176 cell = pool->cell_sort_array[i];
2177 BUG_ON(!cell->holder);
2178
2179
2180
2181
2182
2183
2184 if (ensure_next_mapping(pool)) {
2185 for (j = i; j < count; j++)
2186 list_add(&pool->cell_sort_array[j]->user_list, &cells);
2187
2188 spin_lock_irqsave(&tc->lock, flags);
2189 list_splice(&cells, &tc->deferred_cells);
2190 spin_unlock_irqrestore(&tc->lock, flags);
2191 return;
2192 }
2193
2194 if (bio_op(cell->holder) == REQ_OP_DISCARD)
2195 pool->process_discard_cell(tc, cell);
2196 else
2197 pool->process_cell(tc, cell);
2198 }
2199 } while (!list_empty(&cells));
2200}
2201
2202static void thin_get(struct thin_c *tc);
2203static void thin_put(struct thin_c *tc);
2204
2205
2206
2207
2208
2209
2210static struct thin_c *get_first_thin(struct pool *pool)
2211{
2212 struct thin_c *tc = NULL;
2213
2214 rcu_read_lock();
2215 if (!list_empty(&pool->active_thins)) {
2216 tc = list_entry_rcu(pool->active_thins.next, struct thin_c, list);
2217 thin_get(tc);
2218 }
2219 rcu_read_unlock();
2220
2221 return tc;
2222}
2223
2224static struct thin_c *get_next_thin(struct pool *pool, struct thin_c *tc)
2225{
2226 struct thin_c *old_tc = tc;
2227
2228 rcu_read_lock();
2229 list_for_each_entry_continue_rcu(tc, &pool->active_thins, list) {
2230 thin_get(tc);
2231 thin_put(old_tc);
2232 rcu_read_unlock();
2233 return tc;
2234 }
2235 thin_put(old_tc);
2236 rcu_read_unlock();
2237
2238 return NULL;
2239}
2240
2241static void process_deferred_bios(struct pool *pool)
2242{
2243 unsigned long flags;
2244 struct bio *bio;
2245 struct bio_list bios;
2246 struct thin_c *tc;
2247
2248 tc = get_first_thin(pool);
2249 while (tc) {
2250 process_thin_deferred_cells(tc);
2251 process_thin_deferred_bios(tc);
2252 tc = get_next_thin(pool, tc);
2253 }
2254
2255
2256
2257
2258
2259 bio_list_init(&bios);
2260 spin_lock_irqsave(&pool->lock, flags);
2261 bio_list_merge(&bios, &pool->deferred_flush_bios);
2262 bio_list_init(&pool->deferred_flush_bios);
2263 spin_unlock_irqrestore(&pool->lock, flags);
2264
2265 if (bio_list_empty(&bios) &&
2266 !(dm_pool_changed_this_transaction(pool->pmd) && need_commit_due_to_time(pool)))
2267 return;
2268
2269 if (commit(pool)) {
2270 while ((bio = bio_list_pop(&bios)))
2271 bio_io_error(bio);
2272 return;
2273 }
2274 pool->last_commit_jiffies = jiffies;
2275
2276 while ((bio = bio_list_pop(&bios)))
2277 generic_make_request(bio);
2278}
2279
2280static void do_worker(struct work_struct *ws)
2281{
2282 struct pool *pool = container_of(ws, struct pool, worker);
2283
2284 throttle_work_start(&pool->throttle);
2285 dm_pool_issue_prefetches(pool->pmd);
2286 throttle_work_update(&pool->throttle);
2287 process_prepared(pool, &pool->prepared_mappings, &pool->process_prepared_mapping);
2288 throttle_work_update(&pool->throttle);
2289 process_prepared(pool, &pool->prepared_discards, &pool->process_prepared_discard);
2290 throttle_work_update(&pool->throttle);
2291 process_prepared(pool, &pool->prepared_discards_pt2, &pool->process_prepared_discard_pt2);
2292 throttle_work_update(&pool->throttle);
2293 process_deferred_bios(pool);
2294 throttle_work_complete(&pool->throttle);
2295}
2296
2297
2298
2299
2300
2301static void do_waker(struct work_struct *ws)
2302{
2303 struct pool *pool = container_of(to_delayed_work(ws), struct pool, waker);
2304 wake_worker(pool);
2305 queue_delayed_work(pool->wq, &pool->waker, COMMIT_PERIOD);
2306}
2307
2308static void notify_of_pool_mode_change_to_oods(struct pool *pool);
2309
2310
2311
2312
2313
2314
2315static void do_no_space_timeout(struct work_struct *ws)
2316{
2317 struct pool *pool = container_of(to_delayed_work(ws), struct pool,
2318 no_space_timeout);
2319
2320 if (get_pool_mode(pool) == PM_OUT_OF_DATA_SPACE && !pool->pf.error_if_no_space) {
2321 pool->pf.error_if_no_space = true;
2322 notify_of_pool_mode_change_to_oods(pool);
2323 error_retry_list_with_code(pool, BLK_STS_NOSPC);
2324 }
2325}
2326
2327
2328
2329struct pool_work {
2330 struct work_struct worker;
2331 struct completion complete;
2332};
2333
2334static struct pool_work *to_pool_work(struct work_struct *ws)
2335{
2336 return container_of(ws, struct pool_work, worker);
2337}
2338
2339static void pool_work_complete(struct pool_work *pw)
2340{
2341 complete(&pw->complete);
2342}
2343
2344static void pool_work_wait(struct pool_work *pw, struct pool *pool,
2345 void (*fn)(struct work_struct *))
2346{
2347 INIT_WORK_ONSTACK(&pw->worker, fn);
2348 init_completion(&pw->complete);
2349 queue_work(pool->wq, &pw->worker);
2350 wait_for_completion(&pw->complete);
2351}
2352
2353
2354
2355struct noflush_work {
2356 struct pool_work pw;
2357 struct thin_c *tc;
2358};
2359
2360static struct noflush_work *to_noflush(struct work_struct *ws)
2361{
2362 return container_of(to_pool_work(ws), struct noflush_work, pw);
2363}
2364
2365static void do_noflush_start(struct work_struct *ws)
2366{
2367 struct noflush_work *w = to_noflush(ws);
2368 w->tc->requeue_mode = true;
2369 requeue_io(w->tc);
2370 pool_work_complete(&w->pw);
2371}
2372
2373static void do_noflush_stop(struct work_struct *ws)
2374{
2375 struct noflush_work *w = to_noflush(ws);
2376 w->tc->requeue_mode = false;
2377 pool_work_complete(&w->pw);
2378}
2379
2380static void noflush_work(struct thin_c *tc, void (*fn)(struct work_struct *))
2381{
2382 struct noflush_work w;
2383
2384 w.tc = tc;
2385 pool_work_wait(&w.pw, tc->pool, fn);
2386}
2387
2388
2389
2390static enum pool_mode get_pool_mode(struct pool *pool)
2391{
2392 return pool->pf.mode;
2393}
2394
2395static void notify_of_pool_mode_change(struct pool *pool, const char *new_mode)
2396{
2397 dm_table_event(pool->ti->table);
2398 DMINFO("%s: switching pool to %s mode",
2399 dm_device_name(pool->pool_md), new_mode);
2400}
2401
2402static void notify_of_pool_mode_change_to_oods(struct pool *pool)
2403{
2404 if (!pool->pf.error_if_no_space)
2405 notify_of_pool_mode_change(pool, "out-of-data-space (queue IO)");
2406 else
2407 notify_of_pool_mode_change(pool, "out-of-data-space (error IO)");
2408}
2409
2410static bool passdown_enabled(struct pool_c *pt)
2411{
2412 return pt->adjusted_pf.discard_passdown;
2413}
2414
2415static void set_discard_callbacks(struct pool *pool)
2416{
2417 struct pool_c *pt = pool->ti->private;
2418
2419 if (passdown_enabled(pt)) {
2420 pool->process_discard_cell = process_discard_cell_passdown;
2421 pool->process_prepared_discard = process_prepared_discard_passdown_pt1;
2422 pool->process_prepared_discard_pt2 = process_prepared_discard_passdown_pt2;
2423 } else {
2424 pool->process_discard_cell = process_discard_cell_no_passdown;
2425 pool->process_prepared_discard = process_prepared_discard_no_passdown;
2426 }
2427}
2428
2429static void set_pool_mode(struct pool *pool, enum pool_mode new_mode)
2430{
2431 struct pool_c *pt = pool->ti->private;
2432 bool needs_check = dm_pool_metadata_needs_check(pool->pmd);
2433 enum pool_mode old_mode = get_pool_mode(pool);
2434 unsigned long no_space_timeout = ACCESS_ONCE(no_space_timeout_secs) * HZ;
2435
2436
2437
2438
2439
2440 if (new_mode == PM_WRITE && needs_check) {
2441 DMERR("%s: unable to switch pool to write mode until repaired.",
2442 dm_device_name(pool->pool_md));
2443 if (old_mode != new_mode)
2444 new_mode = old_mode;
2445 else
2446 new_mode = PM_READ_ONLY;
2447 }
2448
2449
2450
2451
2452
2453 if (old_mode == PM_FAIL)
2454 new_mode = old_mode;
2455
2456 switch (new_mode) {
2457 case PM_FAIL:
2458 if (old_mode != new_mode)
2459 notify_of_pool_mode_change(pool, "failure");
2460 dm_pool_metadata_read_only(pool->pmd);
2461 pool->process_bio = process_bio_fail;
2462 pool->process_discard = process_bio_fail;
2463 pool->process_cell = process_cell_fail;
2464 pool->process_discard_cell = process_cell_fail;
2465 pool->process_prepared_mapping = process_prepared_mapping_fail;
2466 pool->process_prepared_discard = process_prepared_discard_fail;
2467
2468 error_retry_list(pool);
2469 break;
2470
2471 case PM_READ_ONLY:
2472 if (old_mode != new_mode)
2473 notify_of_pool_mode_change(pool, "read-only");
2474 dm_pool_metadata_read_only(pool->pmd);
2475 pool->process_bio = process_bio_read_only;
2476 pool->process_discard = process_bio_success;
2477 pool->process_cell = process_cell_read_only;
2478 pool->process_discard_cell = process_cell_success;
2479 pool->process_prepared_mapping = process_prepared_mapping_fail;
2480 pool->process_prepared_discard = process_prepared_discard_success;
2481
2482 error_retry_list(pool);
2483 break;
2484
2485 case PM_OUT_OF_DATA_SPACE:
2486
2487
2488
2489
2490
2491
2492
2493
2494 if (old_mode != new_mode)
2495 notify_of_pool_mode_change_to_oods(pool);
2496 pool->out_of_data_space = true;
2497 pool->process_bio = process_bio_read_only;
2498 pool->process_discard = process_discard_bio;
2499 pool->process_cell = process_cell_read_only;
2500 pool->process_prepared_mapping = process_prepared_mapping;
2501 set_discard_callbacks(pool);
2502
2503 if (!pool->pf.error_if_no_space && no_space_timeout)
2504 queue_delayed_work(pool->wq, &pool->no_space_timeout, no_space_timeout);
2505 break;
2506
2507 case PM_WRITE:
2508 if (old_mode != new_mode)
2509 notify_of_pool_mode_change(pool, "write");
2510 pool->out_of_data_space = false;
2511 pool->pf.error_if_no_space = pt->requested_pf.error_if_no_space;
2512 dm_pool_metadata_read_write(pool->pmd);
2513 pool->process_bio = process_bio;
2514 pool->process_discard = process_discard_bio;
2515 pool->process_cell = process_cell;
2516 pool->process_prepared_mapping = process_prepared_mapping;
2517 set_discard_callbacks(pool);
2518 break;
2519 }
2520
2521 pool->pf.mode = new_mode;
2522
2523
2524
2525
2526 pt->adjusted_pf.mode = new_mode;
2527}
2528
2529static void abort_transaction(struct pool *pool)
2530{
2531 const char *dev_name = dm_device_name(pool->pool_md);
2532
2533 DMERR_LIMIT("%s: aborting current metadata transaction", dev_name);
2534 if (dm_pool_abort_metadata(pool->pmd)) {
2535 DMERR("%s: failed to abort metadata transaction", dev_name);
2536 set_pool_mode(pool, PM_FAIL);
2537 }
2538
2539 if (dm_pool_metadata_set_needs_check(pool->pmd)) {
2540 DMERR("%s: failed to set 'needs_check' flag in metadata", dev_name);
2541 set_pool_mode(pool, PM_FAIL);
2542 }
2543}
2544
2545static void metadata_operation_failed(struct pool *pool, const char *op, int r)
2546{
2547 DMERR_LIMIT("%s: metadata operation '%s' failed: error = %d",
2548 dm_device_name(pool->pool_md), op, r);
2549
2550 abort_transaction(pool);
2551 set_pool_mode(pool, PM_READ_ONLY);
2552}
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563static void thin_defer_bio(struct thin_c *tc, struct bio *bio)
2564{
2565 unsigned long flags;
2566 struct pool *pool = tc->pool;
2567
2568 spin_lock_irqsave(&tc->lock, flags);
2569 bio_list_add(&tc->deferred_bio_list, bio);
2570 spin_unlock_irqrestore(&tc->lock, flags);
2571
2572 wake_worker(pool);
2573}
2574
2575static void thin_defer_bio_with_throttle(struct thin_c *tc, struct bio *bio)
2576{
2577 struct pool *pool = tc->pool;
2578
2579 throttle_lock(&pool->throttle);
2580 thin_defer_bio(tc, bio);
2581 throttle_unlock(&pool->throttle);
2582}
2583
2584static void thin_defer_cell(struct thin_c *tc, struct dm_bio_prison_cell *cell)
2585{
2586 unsigned long flags;
2587 struct pool *pool = tc->pool;
2588
2589 throttle_lock(&pool->throttle);
2590 spin_lock_irqsave(&tc->lock, flags);
2591 list_add_tail(&cell->user_list, &tc->deferred_cells);
2592 spin_unlock_irqrestore(&tc->lock, flags);
2593 throttle_unlock(&pool->throttle);
2594
2595 wake_worker(pool);
2596}
2597
2598static void thin_hook_bio(struct thin_c *tc, struct bio *bio)
2599{
2600 struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook));
2601
2602 h->tc = tc;
2603 h->shared_read_entry = NULL;
2604 h->all_io_entry = NULL;
2605 h->overwrite_mapping = NULL;
2606 h->cell = NULL;
2607}
2608
2609
2610
2611
2612static int thin_bio_map(struct dm_target *ti, struct bio *bio)
2613{
2614 int r;
2615 struct thin_c *tc = ti->private;
2616 dm_block_t block = get_bio_block(tc, bio);
2617 struct dm_thin_device *td = tc->td;
2618 struct dm_thin_lookup_result result;
2619 struct dm_bio_prison_cell *virt_cell, *data_cell;
2620 struct dm_cell_key key;
2621
2622 thin_hook_bio(tc, bio);
2623
2624 if (tc->requeue_mode) {
2625 bio->bi_status = BLK_STS_DM_REQUEUE;
2626 bio_endio(bio);
2627 return DM_MAPIO_SUBMITTED;
2628 }
2629
2630 if (get_pool_mode(tc->pool) == PM_FAIL) {
2631 bio_io_error(bio);
2632 return DM_MAPIO_SUBMITTED;
2633 }
2634
2635 if (op_is_flush(bio->bi_opf) || bio_op(bio) == REQ_OP_DISCARD) {
2636 thin_defer_bio_with_throttle(tc, bio);
2637 return DM_MAPIO_SUBMITTED;
2638 }
2639
2640
2641
2642
2643
2644 build_virtual_key(tc->td, block, &key);
2645 if (bio_detain(tc->pool, &key, bio, &virt_cell))
2646 return DM_MAPIO_SUBMITTED;
2647
2648 r = dm_thin_find_block(td, block, 0, &result);
2649
2650
2651
2652
2653 switch (r) {
2654 case 0:
2655 if (unlikely(result.shared)) {
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670 thin_defer_cell(tc, virt_cell);
2671 return DM_MAPIO_SUBMITTED;
2672 }
2673
2674 build_data_key(tc->td, result.block, &key);
2675 if (bio_detain(tc->pool, &key, bio, &data_cell)) {
2676 cell_defer_no_holder(tc, virt_cell);
2677 return DM_MAPIO_SUBMITTED;
2678 }
2679
2680 inc_all_io_entry(tc->pool, bio);
2681 cell_defer_no_holder(tc, data_cell);
2682 cell_defer_no_holder(tc, virt_cell);
2683
2684 remap(tc, bio, result.block);
2685 return DM_MAPIO_REMAPPED;
2686
2687 case -ENODATA:
2688 case -EWOULDBLOCK:
2689 thin_defer_cell(tc, virt_cell);
2690 return DM_MAPIO_SUBMITTED;
2691
2692 default:
2693
2694
2695
2696
2697
2698 bio_io_error(bio);
2699 cell_defer_no_holder(tc, virt_cell);
2700 return DM_MAPIO_SUBMITTED;
2701 }
2702}
2703
2704static int pool_is_congested(struct dm_target_callbacks *cb, int bdi_bits)
2705{
2706 struct pool_c *pt = container_of(cb, struct pool_c, callbacks);
2707 struct request_queue *q;
2708
2709 if (get_pool_mode(pt->pool) == PM_OUT_OF_DATA_SPACE)
2710 return 1;
2711
2712 q = bdev_get_queue(pt->data_dev->bdev);
2713 return bdi_congested(q->backing_dev_info, bdi_bits);
2714}
2715
2716static void requeue_bios(struct pool *pool)
2717{
2718 unsigned long flags;
2719 struct thin_c *tc;
2720
2721 rcu_read_lock();
2722 list_for_each_entry_rcu(tc, &pool->active_thins, list) {
2723 spin_lock_irqsave(&tc->lock, flags);
2724 bio_list_merge(&tc->deferred_bio_list, &tc->retry_on_resume_list);
2725 bio_list_init(&tc->retry_on_resume_list);
2726 spin_unlock_irqrestore(&tc->lock, flags);
2727 }
2728 rcu_read_unlock();
2729}
2730
2731
2732
2733
2734static bool data_dev_supports_discard(struct pool_c *pt)
2735{
2736 struct request_queue *q = bdev_get_queue(pt->data_dev->bdev);
2737
2738 return q && blk_queue_discard(q);
2739}
2740
2741static bool is_factor(sector_t block_size, uint32_t n)
2742{
2743 return !sector_div(block_size, n);
2744}
2745
2746
2747
2748
2749
2750static void disable_passdown_if_not_supported(struct pool_c *pt)
2751{
2752 struct pool *pool = pt->pool;
2753 struct block_device *data_bdev = pt->data_dev->bdev;
2754 struct queue_limits *data_limits = &bdev_get_queue(data_bdev)->limits;
2755 const char *reason = NULL;
2756 char buf[BDEVNAME_SIZE];
2757
2758 if (!pt->adjusted_pf.discard_passdown)
2759 return;
2760
2761 if (!data_dev_supports_discard(pt))
2762 reason = "discard unsupported";
2763
2764 else if (data_limits->max_discard_sectors < pool->sectors_per_block)
2765 reason = "max discard sectors smaller than a block";
2766
2767 if (reason) {
2768 DMWARN("Data device (%s) %s: Disabling discard passdown.", bdevname(data_bdev, buf), reason);
2769 pt->adjusted_pf.discard_passdown = false;
2770 }
2771}
2772
2773static int bind_control_target(struct pool *pool, struct dm_target *ti)
2774{
2775 struct pool_c *pt = ti->private;
2776
2777
2778
2779
2780 enum pool_mode old_mode = get_pool_mode(pool);
2781 enum pool_mode new_mode = pt->adjusted_pf.mode;
2782
2783
2784
2785
2786
2787
2788 pt->adjusted_pf.mode = old_mode;
2789
2790 pool->ti = ti;
2791 pool->pf = pt->adjusted_pf;
2792 pool->low_water_blocks = pt->low_water_blocks;
2793
2794 set_pool_mode(pool, new_mode);
2795
2796 return 0;
2797}
2798
2799static void unbind_control_target(struct pool *pool, struct dm_target *ti)
2800{
2801 if (pool->ti == ti)
2802 pool->ti = NULL;
2803}
2804
2805
2806
2807
2808
2809static void pool_features_init(struct pool_features *pf)
2810{
2811 pf->mode = PM_WRITE;
2812 pf->zero_new_blocks = true;
2813 pf->discard_enabled = true;
2814 pf->discard_passdown = true;
2815 pf->error_if_no_space = false;
2816}
2817
2818static void __pool_destroy(struct pool *pool)
2819{
2820 __pool_table_remove(pool);
2821
2822 vfree(pool->cell_sort_array);
2823 if (dm_pool_metadata_close(pool->pmd) < 0)
2824 DMWARN("%s: dm_pool_metadata_close() failed.", __func__);
2825
2826 dm_bio_prison_destroy(pool->prison);
2827 dm_kcopyd_client_destroy(pool->copier);
2828
2829 if (pool->wq)
2830 destroy_workqueue(pool->wq);
2831
2832 if (pool->next_mapping)
2833 mempool_free(pool->next_mapping, pool->mapping_pool);
2834 mempool_destroy(pool->mapping_pool);
2835 dm_deferred_set_destroy(pool->shared_read_ds);
2836 dm_deferred_set_destroy(pool->all_io_ds);
2837 kfree(pool);
2838}
2839
2840static struct kmem_cache *_new_mapping_cache;
2841
2842static struct pool *pool_create(struct mapped_device *pool_md,
2843 struct block_device *metadata_dev,
2844 unsigned long block_size,
2845 int read_only, char **error)
2846{
2847 int r;
2848 void *err_p;
2849 struct pool *pool;
2850 struct dm_pool_metadata *pmd;
2851 bool format_device = read_only ? false : true;
2852
2853 pmd = dm_pool_metadata_open(metadata_dev, block_size, format_device);
2854 if (IS_ERR(pmd)) {
2855 *error = "Error creating metadata object";
2856 return (struct pool *)pmd;
2857 }
2858
2859 pool = kmalloc(sizeof(*pool), GFP_KERNEL);
2860 if (!pool) {
2861 *error = "Error allocating memory for pool";
2862 err_p = ERR_PTR(-ENOMEM);
2863 goto bad_pool;
2864 }
2865
2866 pool->pmd = pmd;
2867 pool->sectors_per_block = block_size;
2868 if (block_size & (block_size - 1))
2869 pool->sectors_per_block_shift = -1;
2870 else
2871 pool->sectors_per_block_shift = __ffs(block_size);
2872 pool->low_water_blocks = 0;
2873 pool_features_init(&pool->pf);
2874 pool->prison = dm_bio_prison_create();
2875 if (!pool->prison) {
2876 *error = "Error creating pool's bio prison";
2877 err_p = ERR_PTR(-ENOMEM);
2878 goto bad_prison;
2879 }
2880
2881 pool->copier = dm_kcopyd_client_create(&dm_kcopyd_throttle);
2882 if (IS_ERR(pool->copier)) {
2883 r = PTR_ERR(pool->copier);
2884 *error = "Error creating pool's kcopyd client";
2885 err_p = ERR_PTR(r);
2886 goto bad_kcopyd_client;
2887 }
2888
2889
2890
2891
2892
2893 pool->wq = alloc_ordered_workqueue("dm-" DM_MSG_PREFIX, WQ_MEM_RECLAIM);
2894 if (!pool->wq) {
2895 *error = "Error creating pool's workqueue";
2896 err_p = ERR_PTR(-ENOMEM);
2897 goto bad_wq;
2898 }
2899
2900 throttle_init(&pool->throttle);
2901 INIT_WORK(&pool->worker, do_worker);
2902 INIT_DELAYED_WORK(&pool->waker, do_waker);
2903 INIT_DELAYED_WORK(&pool->no_space_timeout, do_no_space_timeout);
2904 spin_lock_init(&pool->lock);
2905 bio_list_init(&pool->deferred_flush_bios);
2906 INIT_LIST_HEAD(&pool->prepared_mappings);
2907 INIT_LIST_HEAD(&pool->prepared_discards);
2908 INIT_LIST_HEAD(&pool->prepared_discards_pt2);
2909 INIT_LIST_HEAD(&pool->active_thins);
2910 pool->low_water_triggered = false;
2911 pool->suspended = true;
2912 pool->out_of_data_space = false;
2913
2914 pool->shared_read_ds = dm_deferred_set_create();
2915 if (!pool->shared_read_ds) {
2916 *error = "Error creating pool's shared read deferred set";
2917 err_p = ERR_PTR(-ENOMEM);
2918 goto bad_shared_read_ds;
2919 }
2920
2921 pool->all_io_ds = dm_deferred_set_create();
2922 if (!pool->all_io_ds) {
2923 *error = "Error creating pool's all io deferred set";
2924 err_p = ERR_PTR(-ENOMEM);
2925 goto bad_all_io_ds;
2926 }
2927
2928 pool->next_mapping = NULL;
2929 pool->mapping_pool = mempool_create_slab_pool(MAPPING_POOL_SIZE,
2930 _new_mapping_cache);
2931 if (!pool->mapping_pool) {
2932 *error = "Error creating pool's mapping mempool";
2933 err_p = ERR_PTR(-ENOMEM);
2934 goto bad_mapping_pool;
2935 }
2936
2937 pool->cell_sort_array = vmalloc(sizeof(*pool->cell_sort_array) * CELL_SORT_ARRAY_SIZE);
2938 if (!pool->cell_sort_array) {
2939 *error = "Error allocating cell sort array";
2940 err_p = ERR_PTR(-ENOMEM);
2941 goto bad_sort_array;
2942 }
2943
2944 pool->ref_count = 1;
2945 pool->last_commit_jiffies = jiffies;
2946 pool->pool_md = pool_md;
2947 pool->md_dev = metadata_dev;
2948 __pool_table_insert(pool);
2949
2950 return pool;
2951
2952bad_sort_array:
2953 mempool_destroy(pool->mapping_pool);
2954bad_mapping_pool:
2955 dm_deferred_set_destroy(pool->all_io_ds);
2956bad_all_io_ds:
2957 dm_deferred_set_destroy(pool->shared_read_ds);
2958bad_shared_read_ds:
2959 destroy_workqueue(pool->wq);
2960bad_wq:
2961 dm_kcopyd_client_destroy(pool->copier);
2962bad_kcopyd_client:
2963 dm_bio_prison_destroy(pool->prison);
2964bad_prison:
2965 kfree(pool);
2966bad_pool:
2967 if (dm_pool_metadata_close(pmd))
2968 DMWARN("%s: dm_pool_metadata_close() failed.", __func__);
2969
2970 return err_p;
2971}
2972
2973static void __pool_inc(struct pool *pool)
2974{
2975 BUG_ON(!mutex_is_locked(&dm_thin_pool_table.mutex));
2976 pool->ref_count++;
2977}
2978
2979static void __pool_dec(struct pool *pool)
2980{
2981 BUG_ON(!mutex_is_locked(&dm_thin_pool_table.mutex));
2982 BUG_ON(!pool->ref_count);
2983 if (!--pool->ref_count)
2984 __pool_destroy(pool);
2985}
2986
2987static struct pool *__pool_find(struct mapped_device *pool_md,
2988 struct block_device *metadata_dev,
2989 unsigned long block_size, int read_only,
2990 char **error, int *created)
2991{
2992 struct pool *pool = __pool_table_lookup_metadata_dev(metadata_dev);
2993
2994 if (pool) {
2995 if (pool->pool_md != pool_md) {
2996 *error = "metadata device already in use by a pool";
2997 return ERR_PTR(-EBUSY);
2998 }
2999 __pool_inc(pool);
3000
3001 } else {
3002 pool = __pool_table_lookup(pool_md);
3003 if (pool) {
3004 if (pool->md_dev != metadata_dev) {
3005 *error = "different pool cannot replace a pool";
3006 return ERR_PTR(-EINVAL);
3007 }
3008 __pool_inc(pool);
3009
3010 } else {
3011 pool = pool_create(pool_md, metadata_dev, block_size, read_only, error);
3012 *created = 1;
3013 }
3014 }
3015
3016 return pool;
3017}
3018
3019
3020
3021
3022static void pool_dtr(struct dm_target *ti)
3023{
3024 struct pool_c *pt = ti->private;
3025
3026 mutex_lock(&dm_thin_pool_table.mutex);
3027
3028 unbind_control_target(pt->pool, ti);
3029 __pool_dec(pt->pool);
3030 dm_put_device(ti, pt->metadata_dev);
3031 dm_put_device(ti, pt->data_dev);
3032 kfree(pt);
3033
3034 mutex_unlock(&dm_thin_pool_table.mutex);
3035}
3036
3037static int parse_pool_features(struct dm_arg_set *as, struct pool_features *pf,
3038 struct dm_target *ti)
3039{
3040 int r;
3041 unsigned argc;
3042 const char *arg_name;
3043
3044 static const struct dm_arg _args[] = {
3045 {0, 4, "Invalid number of pool feature arguments"},
3046 };
3047
3048
3049
3050
3051 if (!as->argc)
3052 return 0;
3053
3054 r = dm_read_arg_group(_args, as, &argc, &ti->error);
3055 if (r)
3056 return -EINVAL;
3057
3058 while (argc && !r) {
3059 arg_name = dm_shift_arg(as);
3060 argc--;
3061
3062 if (!strcasecmp(arg_name, "skip_block_zeroing"))
3063 pf->zero_new_blocks = false;
3064
3065 else if (!strcasecmp(arg_name, "ignore_discard"))
3066 pf->discard_enabled = false;
3067
3068 else if (!strcasecmp(arg_name, "no_discard_passdown"))
3069 pf->discard_passdown = false;
3070
3071 else if (!strcasecmp(arg_name, "read_only"))
3072 pf->mode = PM_READ_ONLY;
3073
3074 else if (!strcasecmp(arg_name, "error_if_no_space"))
3075 pf->error_if_no_space = true;
3076
3077 else {
3078 ti->error = "Unrecognised pool feature requested";
3079 r = -EINVAL;
3080 break;
3081 }
3082 }
3083
3084 return r;
3085}
3086
3087static void metadata_low_callback(void *context)
3088{
3089 struct pool *pool = context;
3090
3091 DMWARN("%s: reached low water mark for metadata device: sending event.",
3092 dm_device_name(pool->pool_md));
3093
3094 dm_table_event(pool->ti->table);
3095}
3096
3097static sector_t get_dev_size(struct block_device *bdev)
3098{
3099 return i_size_read(bdev->bd_inode) >> SECTOR_SHIFT;
3100}
3101
3102static void warn_if_metadata_device_too_big(struct block_device *bdev)
3103{
3104 sector_t metadata_dev_size = get_dev_size(bdev);
3105 char buffer[BDEVNAME_SIZE];
3106
3107 if (metadata_dev_size > THIN_METADATA_MAX_SECTORS_WARNING)
3108 DMWARN("Metadata device %s is larger than %u sectors: excess space will not be used.",
3109 bdevname(bdev, buffer), THIN_METADATA_MAX_SECTORS);
3110}
3111
3112static sector_t get_metadata_dev_size(struct block_device *bdev)
3113{
3114 sector_t metadata_dev_size = get_dev_size(bdev);
3115
3116 if (metadata_dev_size > THIN_METADATA_MAX_SECTORS)
3117 metadata_dev_size = THIN_METADATA_MAX_SECTORS;
3118
3119 return metadata_dev_size;
3120}
3121
3122static dm_block_t get_metadata_dev_size_in_blocks(struct block_device *bdev)
3123{
3124 sector_t metadata_dev_size = get_metadata_dev_size(bdev);
3125
3126 sector_div(metadata_dev_size, THIN_METADATA_BLOCK_SIZE);
3127
3128 return metadata_dev_size;
3129}
3130
3131
3132
3133
3134
3135
3136
3137static dm_block_t calc_metadata_threshold(struct pool_c *pt)
3138{
3139
3140
3141
3142
3143
3144 dm_block_t quarter = get_metadata_dev_size_in_blocks(pt->metadata_dev->bdev) / 4;
3145 return min((dm_block_t)1024ULL , quarter);
3146}
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161static int pool_ctr(struct dm_target *ti, unsigned argc, char **argv)
3162{
3163 int r, pool_created = 0;
3164 struct pool_c *pt;
3165 struct pool *pool;
3166 struct pool_features pf;
3167 struct dm_arg_set as;
3168 struct dm_dev *data_dev;
3169 unsigned long block_size;
3170 dm_block_t low_water_blocks;
3171 struct dm_dev *metadata_dev;
3172 fmode_t metadata_mode;
3173
3174
3175
3176
3177 mutex_lock(&dm_thin_pool_table.mutex);
3178
3179 if (argc < 4) {
3180 ti->error = "Invalid argument count";
3181 r = -EINVAL;
3182 goto out_unlock;
3183 }
3184
3185 as.argc = argc;
3186 as.argv = argv;
3187
3188
3189
3190
3191 pool_features_init(&pf);
3192
3193 dm_consume_args(&as, 4);
3194 r = parse_pool_features(&as, &pf, ti);
3195 if (r)
3196 goto out_unlock;
3197
3198 metadata_mode = FMODE_READ | ((pf.mode == PM_READ_ONLY) ? 0 : FMODE_WRITE);
3199 r = dm_get_device(ti, argv[0], metadata_mode, &metadata_dev);
3200 if (r) {
3201 ti->error = "Error opening metadata block device";
3202 goto out_unlock;
3203 }
3204 warn_if_metadata_device_too_big(metadata_dev->bdev);
3205
3206 r = dm_get_device(ti, argv[1], FMODE_READ | FMODE_WRITE, &data_dev);
3207 if (r) {
3208 ti->error = "Error getting data device";
3209 goto out_metadata;
3210 }
3211
3212 if (kstrtoul(argv[2], 10, &block_size) || !block_size ||
3213 block_size < DATA_DEV_BLOCK_SIZE_MIN_SECTORS ||
3214 block_size > DATA_DEV_BLOCK_SIZE_MAX_SECTORS ||
3215 block_size & (DATA_DEV_BLOCK_SIZE_MIN_SECTORS - 1)) {
3216 ti->error = "Invalid block size";
3217 r = -EINVAL;
3218 goto out;
3219 }
3220
3221 if (kstrtoull(argv[3], 10, (unsigned long long *)&low_water_blocks)) {
3222 ti->error = "Invalid low water mark";
3223 r = -EINVAL;
3224 goto out;
3225 }
3226
3227 pt = kzalloc(sizeof(*pt), GFP_KERNEL);
3228 if (!pt) {
3229 r = -ENOMEM;
3230 goto out;
3231 }
3232
3233 pool = __pool_find(dm_table_get_md(ti->table), metadata_dev->bdev,
3234 block_size, pf.mode == PM_READ_ONLY, &ti->error, &pool_created);
3235 if (IS_ERR(pool)) {
3236 r = PTR_ERR(pool);
3237 goto out_free_pt;
3238 }
3239
3240
3241
3242
3243
3244
3245
3246 if (!pool_created && pf.discard_enabled != pool->pf.discard_enabled) {
3247 ti->error = "Discard support cannot be disabled once enabled";
3248 r = -EINVAL;
3249 goto out_flags_changed;
3250 }
3251
3252 pt->pool = pool;
3253 pt->ti = ti;
3254 pt->metadata_dev = metadata_dev;
3255 pt->data_dev = data_dev;
3256 pt->low_water_blocks = low_water_blocks;
3257 pt->adjusted_pf = pt->requested_pf = pf;
3258 ti->num_flush_bios = 1;
3259
3260
3261
3262
3263
3264
3265 if (pf.discard_enabled && pf.discard_passdown) {
3266 ti->num_discard_bios = 1;
3267
3268
3269
3270
3271
3272
3273 ti->discards_supported = true;
3274 }
3275 ti->private = pt;
3276
3277 r = dm_pool_register_metadata_threshold(pt->pool->pmd,
3278 calc_metadata_threshold(pt),
3279 metadata_low_callback,
3280 pool);
3281 if (r)
3282 goto out_flags_changed;
3283
3284 pt->callbacks.congested_fn = pool_is_congested;
3285 dm_table_add_target_callbacks(ti->table, &pt->callbacks);
3286
3287 mutex_unlock(&dm_thin_pool_table.mutex);
3288
3289 return 0;
3290
3291out_flags_changed:
3292 __pool_dec(pool);
3293out_free_pt:
3294 kfree(pt);
3295out:
3296 dm_put_device(ti, data_dev);
3297out_metadata:
3298 dm_put_device(ti, metadata_dev);
3299out_unlock:
3300 mutex_unlock(&dm_thin_pool_table.mutex);
3301
3302 return r;
3303}
3304
3305static int pool_map(struct dm_target *ti, struct bio *bio)
3306{
3307 int r;
3308 struct pool_c *pt = ti->private;
3309 struct pool *pool = pt->pool;
3310 unsigned long flags;
3311
3312
3313
3314
3315 spin_lock_irqsave(&pool->lock, flags);
3316 bio_set_dev(bio, pt->data_dev->bdev);
3317 r = DM_MAPIO_REMAPPED;
3318 spin_unlock_irqrestore(&pool->lock, flags);
3319
3320 return r;
3321}
3322
3323static int maybe_resize_data_dev(struct dm_target *ti, bool *need_commit)
3324{
3325 int r;
3326 struct pool_c *pt = ti->private;
3327 struct pool *pool = pt->pool;
3328 sector_t data_size = ti->len;
3329 dm_block_t sb_data_size;
3330
3331 *need_commit = false;
3332
3333 (void) sector_div(data_size, pool->sectors_per_block);
3334
3335 r = dm_pool_get_data_dev_size(pool->pmd, &sb_data_size);
3336 if (r) {
3337 DMERR("%s: failed to retrieve data device size",
3338 dm_device_name(pool->pool_md));
3339 return r;
3340 }
3341
3342 if (data_size < sb_data_size) {
3343 DMERR("%s: pool target (%llu blocks) too small: expected %llu",
3344 dm_device_name(pool->pool_md),
3345 (unsigned long long)data_size, sb_data_size);
3346 return -EINVAL;
3347
3348 } else if (data_size > sb_data_size) {
3349 if (dm_pool_metadata_needs_check(pool->pmd)) {
3350 DMERR("%s: unable to grow the data device until repaired.",
3351 dm_device_name(pool->pool_md));
3352 return 0;
3353 }
3354
3355 if (sb_data_size)
3356 DMINFO("%s: growing the data device from %llu to %llu blocks",
3357 dm_device_name(pool->pool_md),
3358 sb_data_size, (unsigned long long)data_size);
3359 r = dm_pool_resize_data_dev(pool->pmd, data_size);
3360 if (r) {
3361 metadata_operation_failed(pool, "dm_pool_resize_data_dev", r);
3362 return r;
3363 }
3364
3365 *need_commit = true;
3366 }
3367
3368 return 0;
3369}
3370
3371static int maybe_resize_metadata_dev(struct dm_target *ti, bool *need_commit)
3372{
3373 int r;
3374 struct pool_c *pt = ti->private;
3375 struct pool *pool = pt->pool;
3376 dm_block_t metadata_dev_size, sb_metadata_dev_size;
3377
3378 *need_commit = false;
3379
3380 metadata_dev_size = get_metadata_dev_size_in_blocks(pool->md_dev);
3381
3382 r = dm_pool_get_metadata_dev_size(pool->pmd, &sb_metadata_dev_size);
3383 if (r) {
3384 DMERR("%s: failed to retrieve metadata device size",
3385 dm_device_name(pool->pool_md));
3386 return r;
3387 }
3388
3389 if (metadata_dev_size < sb_metadata_dev_size) {
3390 DMERR("%s: metadata device (%llu blocks) too small: expected %llu",
3391 dm_device_name(pool->pool_md),
3392 metadata_dev_size, sb_metadata_dev_size);
3393 return -EINVAL;
3394
3395 } else if (metadata_dev_size > sb_metadata_dev_size) {
3396 if (dm_pool_metadata_needs_check(pool->pmd)) {
3397 DMERR("%s: unable to grow the metadata device until repaired.",
3398 dm_device_name(pool->pool_md));
3399 return 0;
3400 }
3401
3402 warn_if_metadata_device_too_big(pool->md_dev);
3403 DMINFO("%s: growing the metadata device from %llu to %llu blocks",
3404 dm_device_name(pool->pool_md),
3405 sb_metadata_dev_size, metadata_dev_size);
3406 r = dm_pool_resize_metadata_dev(pool->pmd, metadata_dev_size);
3407 if (r) {
3408 metadata_operation_failed(pool, "dm_pool_resize_metadata_dev", r);
3409 return r;
3410 }
3411
3412 *need_commit = true;
3413 }
3414
3415 return 0;
3416}
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429static int pool_preresume(struct dm_target *ti)
3430{
3431 int r;
3432 bool need_commit1, need_commit2;
3433 struct pool_c *pt = ti->private;
3434 struct pool *pool = pt->pool;
3435
3436
3437
3438
3439 r = bind_control_target(pool, ti);
3440 if (r)
3441 return r;
3442
3443 r = maybe_resize_data_dev(ti, &need_commit1);
3444 if (r)
3445 return r;
3446
3447 r = maybe_resize_metadata_dev(ti, &need_commit2);
3448 if (r)
3449 return r;
3450
3451 if (need_commit1 || need_commit2)
3452 (void) commit(pool);
3453
3454 return 0;
3455}
3456
3457static void pool_suspend_active_thins(struct pool *pool)
3458{
3459 struct thin_c *tc;
3460
3461
3462 tc = get_first_thin(pool);
3463 while (tc) {
3464 dm_internal_suspend_noflush(tc->thin_md);
3465 tc = get_next_thin(pool, tc);
3466 }
3467}
3468
3469static void pool_resume_active_thins(struct pool *pool)
3470{
3471 struct thin_c *tc;
3472
3473
3474 tc = get_first_thin(pool);
3475 while (tc) {
3476 dm_internal_resume(tc->thin_md);
3477 tc = get_next_thin(pool, tc);
3478 }
3479}
3480
3481static void pool_resume(struct dm_target *ti)
3482{
3483 struct pool_c *pt = ti->private;
3484 struct pool *pool = pt->pool;
3485 unsigned long flags;
3486
3487
3488
3489
3490
3491 requeue_bios(pool);
3492 pool_resume_active_thins(pool);
3493
3494 spin_lock_irqsave(&pool->lock, flags);
3495 pool->low_water_triggered = false;
3496 pool->suspended = false;
3497 spin_unlock_irqrestore(&pool->lock, flags);
3498
3499 do_waker(&pool->waker.work);
3500}
3501
3502static void pool_presuspend(struct dm_target *ti)
3503{
3504 struct pool_c *pt = ti->private;
3505 struct pool *pool = pt->pool;
3506 unsigned long flags;
3507
3508 spin_lock_irqsave(&pool->lock, flags);
3509 pool->suspended = true;
3510 spin_unlock_irqrestore(&pool->lock, flags);
3511
3512 pool_suspend_active_thins(pool);
3513}
3514
3515static void pool_presuspend_undo(struct dm_target *ti)
3516{
3517 struct pool_c *pt = ti->private;
3518 struct pool *pool = pt->pool;
3519 unsigned long flags;
3520
3521 pool_resume_active_thins(pool);
3522
3523 spin_lock_irqsave(&pool->lock, flags);
3524 pool->suspended = false;
3525 spin_unlock_irqrestore(&pool->lock, flags);
3526}
3527
3528static void pool_postsuspend(struct dm_target *ti)
3529{
3530 struct pool_c *pt = ti->private;
3531 struct pool *pool = pt->pool;
3532
3533 cancel_delayed_work_sync(&pool->waker);
3534 cancel_delayed_work_sync(&pool->no_space_timeout);
3535 flush_workqueue(pool->wq);
3536 (void) commit(pool);
3537}
3538
3539static int check_arg_count(unsigned argc, unsigned args_required)
3540{
3541 if (argc != args_required) {
3542 DMWARN("Message received with %u arguments instead of %u.",
3543 argc, args_required);
3544 return -EINVAL;
3545 }
3546
3547 return 0;
3548}
3549
3550static int read_dev_id(char *arg, dm_thin_id *dev_id, int warning)
3551{
3552 if (!kstrtoull(arg, 10, (unsigned long long *)dev_id) &&
3553 *dev_id <= MAX_DEV_ID)
3554 return 0;
3555
3556 if (warning)
3557 DMWARN("Message received with invalid device id: %s", arg);
3558
3559 return -EINVAL;
3560}
3561
3562static int process_create_thin_mesg(unsigned argc, char **argv, struct pool *pool)
3563{
3564 dm_thin_id dev_id;
3565 int r;
3566
3567 r = check_arg_count(argc, 2);
3568 if (r)
3569 return r;
3570
3571 r = read_dev_id(argv[1], &dev_id, 1);
3572 if (r)
3573 return r;
3574
3575 r = dm_pool_create_thin(pool->pmd, dev_id);
3576 if (r) {
3577 DMWARN("Creation of new thinly-provisioned device with id %s failed.",
3578 argv[1]);
3579 return r;
3580 }
3581
3582 return 0;
3583}
3584
3585static int process_create_snap_mesg(unsigned argc, char **argv, struct pool *pool)
3586{
3587 dm_thin_id dev_id;
3588 dm_thin_id origin_dev_id;
3589 int r;
3590
3591 r = check_arg_count(argc, 3);
3592 if (r)
3593 return r;
3594
3595 r = read_dev_id(argv[1], &dev_id, 1);
3596 if (r)
3597 return r;
3598
3599 r = read_dev_id(argv[2], &origin_dev_id, 1);
3600 if (r)
3601 return r;
3602
3603 r = dm_pool_create_snap(pool->pmd, dev_id, origin_dev_id);
3604 if (r) {
3605 DMWARN("Creation of new snapshot %s of device %s failed.",
3606 argv[1], argv[2]);
3607 return r;
3608 }
3609
3610 return 0;
3611}
3612
3613static int process_delete_mesg(unsigned argc, char **argv, struct pool *pool)
3614{
3615 dm_thin_id dev_id;
3616 int r;
3617
3618 r = check_arg_count(argc, 2);
3619 if (r)
3620 return r;
3621
3622 r = read_dev_id(argv[1], &dev_id, 1);
3623 if (r)
3624 return r;
3625
3626 r = dm_pool_delete_thin_device(pool->pmd, dev_id);
3627 if (r)
3628 DMWARN("Deletion of thin device %s failed.", argv[1]);
3629
3630 return r;
3631}
3632
3633static int process_set_transaction_id_mesg(unsigned argc, char **argv, struct pool *pool)
3634{
3635 dm_thin_id old_id, new_id;
3636 int r;
3637
3638 r = check_arg_count(argc, 3);
3639 if (r)
3640 return r;
3641
3642 if (kstrtoull(argv[1], 10, (unsigned long long *)&old_id)) {
3643 DMWARN("set_transaction_id message: Unrecognised id %s.", argv[1]);
3644 return -EINVAL;
3645 }
3646
3647 if (kstrtoull(argv[2], 10, (unsigned long long *)&new_id)) {
3648 DMWARN("set_transaction_id message: Unrecognised new id %s.", argv[2]);
3649 return -EINVAL;
3650 }
3651
3652 r = dm_pool_set_metadata_transaction_id(pool->pmd, old_id, new_id);
3653 if (r) {
3654 DMWARN("Failed to change transaction id from %s to %s.",
3655 argv[1], argv[2]);
3656 return r;
3657 }
3658
3659 return 0;
3660}
3661
3662static int process_reserve_metadata_snap_mesg(unsigned argc, char **argv, struct pool *pool)
3663{
3664 int r;
3665
3666 r = check_arg_count(argc, 1);
3667 if (r)
3668 return r;
3669
3670 (void) commit(pool);
3671
3672 r = dm_pool_reserve_metadata_snap(pool->pmd);
3673 if (r)
3674 DMWARN("reserve_metadata_snap message failed.");
3675
3676 return r;
3677}
3678
3679static int process_release_metadata_snap_mesg(unsigned argc, char **argv, struct pool *pool)
3680{
3681 int r;
3682
3683 r = check_arg_count(argc, 1);
3684 if (r)
3685 return r;
3686
3687 r = dm_pool_release_metadata_snap(pool->pmd);
3688 if (r)
3689 DMWARN("release_metadata_snap message failed.");
3690
3691 return r;
3692}
3693
3694
3695
3696
3697
3698
3699
3700
3701
3702
3703static int pool_message(struct dm_target *ti, unsigned argc, char **argv)
3704{
3705 int r = -EINVAL;
3706 struct pool_c *pt = ti->private;
3707 struct pool *pool = pt->pool;
3708
3709 if (get_pool_mode(pool) >= PM_READ_ONLY) {
3710 DMERR("%s: unable to service pool target messages in READ_ONLY or FAIL mode",
3711 dm_device_name(pool->pool_md));
3712 return -EOPNOTSUPP;
3713 }
3714
3715 if (!strcasecmp(argv[0], "create_thin"))
3716 r = process_create_thin_mesg(argc, argv, pool);
3717
3718 else if (!strcasecmp(argv[0], "create_snap"))
3719 r = process_create_snap_mesg(argc, argv, pool);
3720
3721 else if (!strcasecmp(argv[0], "delete"))
3722 r = process_delete_mesg(argc, argv, pool);
3723
3724 else if (!strcasecmp(argv[0], "set_transaction_id"))
3725 r = process_set_transaction_id_mesg(argc, argv, pool);
3726
3727 else if (!strcasecmp(argv[0], "reserve_metadata_snap"))
3728 r = process_reserve_metadata_snap_mesg(argc, argv, pool);
3729
3730 else if (!strcasecmp(argv[0], "release_metadata_snap"))
3731 r = process_release_metadata_snap_mesg(argc, argv, pool);
3732
3733 else
3734 DMWARN("Unrecognised thin pool target message received: %s", argv[0]);
3735
3736 if (!r)
3737 (void) commit(pool);
3738
3739 return r;
3740}
3741
3742static void emit_flags(struct pool_features *pf, char *result,
3743 unsigned sz, unsigned maxlen)
3744{
3745 unsigned count = !pf->zero_new_blocks + !pf->discard_enabled +
3746 !pf->discard_passdown + (pf->mode == PM_READ_ONLY) +
3747 pf->error_if_no_space;
3748 DMEMIT("%u ", count);
3749
3750 if (!pf->zero_new_blocks)
3751 DMEMIT("skip_block_zeroing ");
3752
3753 if (!pf->discard_enabled)
3754 DMEMIT("ignore_discard ");
3755
3756 if (!pf->discard_passdown)
3757 DMEMIT("no_discard_passdown ");
3758
3759 if (pf->mode == PM_READ_ONLY)
3760 DMEMIT("read_only ");
3761
3762 if (pf->error_if_no_space)
3763 DMEMIT("error_if_no_space ");
3764}
3765
3766
3767
3768
3769
3770
3771
3772static void pool_status(struct dm_target *ti, status_type_t type,
3773 unsigned status_flags, char *result, unsigned maxlen)
3774{
3775 int r;
3776 unsigned sz = 0;
3777 uint64_t transaction_id;
3778 dm_block_t nr_free_blocks_data;
3779 dm_block_t nr_free_blocks_metadata;
3780 dm_block_t nr_blocks_data;
3781 dm_block_t nr_blocks_metadata;
3782 dm_block_t held_root;
3783 char buf[BDEVNAME_SIZE];
3784 char buf2[BDEVNAME_SIZE];
3785 struct pool_c *pt = ti->private;
3786 struct pool *pool = pt->pool;
3787
3788 switch (type) {
3789 case STATUSTYPE_INFO:
3790 if (get_pool_mode(pool) == PM_FAIL) {
3791 DMEMIT("Fail");
3792 break;
3793 }
3794
3795
3796 if (!(status_flags & DM_STATUS_NOFLUSH_FLAG) && !dm_suspended(ti))
3797 (void) commit(pool);
3798
3799 r = dm_pool_get_metadata_transaction_id(pool->pmd, &transaction_id);
3800 if (r) {
3801 DMERR("%s: dm_pool_get_metadata_transaction_id returned %d",
3802 dm_device_name(pool->pool_md), r);
3803 goto err;
3804 }
3805
3806 r = dm_pool_get_free_metadata_block_count(pool->pmd, &nr_free_blocks_metadata);
3807 if (r) {
3808 DMERR("%s: dm_pool_get_free_metadata_block_count returned %d",
3809 dm_device_name(pool->pool_md), r);
3810 goto err;
3811 }
3812
3813 r = dm_pool_get_metadata_dev_size(pool->pmd, &nr_blocks_metadata);
3814 if (r) {
3815 DMERR("%s: dm_pool_get_metadata_dev_size returned %d",
3816 dm_device_name(pool->pool_md), r);
3817 goto err;
3818 }
3819
3820 r = dm_pool_get_free_block_count(pool->pmd, &nr_free_blocks_data);
3821 if (r) {
3822 DMERR("%s: dm_pool_get_free_block_count returned %d",
3823 dm_device_name(pool->pool_md), r);
3824 goto err;
3825 }
3826
3827 r = dm_pool_get_data_dev_size(pool->pmd, &nr_blocks_data);
3828 if (r) {
3829 DMERR("%s: dm_pool_get_data_dev_size returned %d",
3830 dm_device_name(pool->pool_md), r);
3831 goto err;
3832 }
3833
3834 r = dm_pool_get_metadata_snap(pool->pmd, &held_root);
3835 if (r) {
3836 DMERR("%s: dm_pool_get_metadata_snap returned %d",
3837 dm_device_name(pool->pool_md), r);
3838 goto err;
3839 }
3840
3841 DMEMIT("%llu %llu/%llu %llu/%llu ",
3842 (unsigned long long)transaction_id,
3843 (unsigned long long)(nr_blocks_metadata - nr_free_blocks_metadata),
3844 (unsigned long long)nr_blocks_metadata,
3845 (unsigned long long)(nr_blocks_data - nr_free_blocks_data),
3846 (unsigned long long)nr_blocks_data);
3847
3848 if (held_root)
3849 DMEMIT("%llu ", held_root);
3850 else
3851 DMEMIT("- ");
3852
3853 if (pool->pf.mode == PM_OUT_OF_DATA_SPACE)
3854 DMEMIT("out_of_data_space ");
3855 else if (pool->pf.mode == PM_READ_ONLY)
3856 DMEMIT("ro ");
3857 else
3858 DMEMIT("rw ");
3859
3860 if (!pool->pf.discard_enabled)
3861 DMEMIT("ignore_discard ");
3862 else if (pool->pf.discard_passdown)
3863 DMEMIT("discard_passdown ");
3864 else
3865 DMEMIT("no_discard_passdown ");
3866
3867 if (pool->pf.error_if_no_space)
3868 DMEMIT("error_if_no_space ");
3869 else
3870 DMEMIT("queue_if_no_space ");
3871
3872 if (dm_pool_metadata_needs_check(pool->pmd))
3873 DMEMIT("needs_check ");
3874 else
3875 DMEMIT("- ");
3876
3877 break;
3878
3879 case STATUSTYPE_TABLE:
3880 DMEMIT("%s %s %lu %llu ",
3881 format_dev_t(buf, pt->metadata_dev->bdev->bd_dev),
3882 format_dev_t(buf2, pt->data_dev->bdev->bd_dev),
3883 (unsigned long)pool->sectors_per_block,
3884 (unsigned long long)pt->low_water_blocks);
3885 emit_flags(&pt->requested_pf, result, sz, maxlen);
3886 break;
3887 }
3888 return;
3889
3890err:
3891 DMEMIT("Error");
3892}
3893
3894static int pool_iterate_devices(struct dm_target *ti,
3895 iterate_devices_callout_fn fn, void *data)
3896{
3897 struct pool_c *pt = ti->private;
3898
3899 return fn(ti, pt->data_dev, 0, ti->len, data);
3900}
3901
3902static void pool_io_hints(struct dm_target *ti, struct queue_limits *limits)
3903{
3904 struct pool_c *pt = ti->private;
3905 struct pool *pool = pt->pool;
3906 sector_t io_opt_sectors = limits->io_opt >> SECTOR_SHIFT;
3907
3908
3909
3910
3911
3912
3913
3914
3915
3916
3917 if (limits->max_sectors < pool->sectors_per_block) {
3918 while (!is_factor(pool->sectors_per_block, limits->max_sectors)) {
3919 if ((limits->max_sectors & (limits->max_sectors - 1)) == 0)
3920 limits->max_sectors--;
3921 limits->max_sectors = rounddown_pow_of_two(limits->max_sectors);
3922 }
3923 }
3924
3925
3926
3927
3928
3929 if (io_opt_sectors < pool->sectors_per_block ||
3930 !is_factor(io_opt_sectors, pool->sectors_per_block)) {
3931 if (is_factor(pool->sectors_per_block, limits->max_sectors))
3932 blk_limits_io_min(limits, limits->max_sectors << SECTOR_SHIFT);
3933 else
3934 blk_limits_io_min(limits, pool->sectors_per_block << SECTOR_SHIFT);
3935 blk_limits_io_opt(limits, pool->sectors_per_block << SECTOR_SHIFT);
3936 }
3937
3938
3939
3940
3941
3942
3943 if (!pt->adjusted_pf.discard_enabled) {
3944
3945
3946
3947
3948
3949
3950 limits->discard_granularity = 0;
3951 return;
3952 }
3953
3954 disable_passdown_if_not_supported(pt);
3955
3956
3957
3958
3959
3960}
3961
3962static struct target_type pool_target = {
3963 .name = "thin-pool",
3964 .features = DM_TARGET_SINGLETON | DM_TARGET_ALWAYS_WRITEABLE |
3965 DM_TARGET_IMMUTABLE,
3966 .version = {1, 19, 0},
3967 .module = THIS_MODULE,
3968 .ctr = pool_ctr,
3969 .dtr = pool_dtr,
3970 .map = pool_map,
3971 .presuspend = pool_presuspend,
3972 .presuspend_undo = pool_presuspend_undo,
3973 .postsuspend = pool_postsuspend,
3974 .preresume = pool_preresume,
3975 .resume = pool_resume,
3976 .message = pool_message,
3977 .status = pool_status,
3978 .iterate_devices = pool_iterate_devices,
3979 .io_hints = pool_io_hints,
3980};
3981
3982
3983
3984
3985static void thin_get(struct thin_c *tc)
3986{
3987 atomic_inc(&tc->refcount);
3988}
3989
3990static void thin_put(struct thin_c *tc)
3991{
3992 if (atomic_dec_and_test(&tc->refcount))
3993 complete(&tc->can_destroy);
3994}
3995
3996static void thin_dtr(struct dm_target *ti)
3997{
3998 struct thin_c *tc = ti->private;
3999 unsigned long flags;
4000
4001 spin_lock_irqsave(&tc->pool->lock, flags);
4002 list_del_rcu(&tc->list);
4003 spin_unlock_irqrestore(&tc->pool->lock, flags);
4004 synchronize_rcu();
4005
4006 thin_put(tc);
4007 wait_for_completion(&tc->can_destroy);
4008
4009 mutex_lock(&dm_thin_pool_table.mutex);
4010
4011 __pool_dec(tc->pool);
4012 dm_pool_close_thin_device(tc->td);
4013 dm_put_device(ti, tc->pool_dev);
4014 if (tc->origin_dev)
4015 dm_put_device(ti, tc->origin_dev);
4016 kfree(tc);
4017
4018 mutex_unlock(&dm_thin_pool_table.mutex);
4019}
4020
4021
4022
4023
4024
4025
4026
4027
4028
4029
4030
4031
4032
4033static int thin_ctr(struct dm_target *ti, unsigned argc, char **argv)
4034{
4035 int r;
4036 struct thin_c *tc;
4037 struct dm_dev *pool_dev, *origin_dev;
4038 struct mapped_device *pool_md;
4039 unsigned long flags;
4040
4041 mutex_lock(&dm_thin_pool_table.mutex);
4042
4043 if (argc != 2 && argc != 3) {
4044 ti->error = "Invalid argument count";
4045 r = -EINVAL;
4046 goto out_unlock;
4047 }
4048
4049 tc = ti->private = kzalloc(sizeof(*tc), GFP_KERNEL);
4050 if (!tc) {
4051 ti->error = "Out of memory";
4052 r = -ENOMEM;
4053 goto out_unlock;
4054 }
4055 tc->thin_md = dm_table_get_md(ti->table);
4056 spin_lock_init(&tc->lock);
4057 INIT_LIST_HEAD(&tc->deferred_cells);
4058 bio_list_init(&tc->deferred_bio_list);
4059 bio_list_init(&tc->retry_on_resume_list);
4060 tc->sort_bio_list = RB_ROOT;
4061
4062 if (argc == 3) {
4063 r = dm_get_device(ti, argv[2], FMODE_READ, &origin_dev);
4064 if (r) {
4065 ti->error = "Error opening origin device";
4066 goto bad_origin_dev;
4067 }
4068 tc->origin_dev = origin_dev;
4069 }
4070
4071 r = dm_get_device(ti, argv[0], dm_table_get_mode(ti->table), &pool_dev);
4072 if (r) {
4073 ti->error = "Error opening pool device";
4074 goto bad_pool_dev;
4075 }
4076 tc->pool_dev = pool_dev;
4077
4078 if (read_dev_id(argv[1], (unsigned long long *)&tc->dev_id, 0)) {
4079 ti->error = "Invalid device id";
4080 r = -EINVAL;
4081 goto bad_common;
4082 }
4083
4084 pool_md = dm_get_md(tc->pool_dev->bdev->bd_dev);
4085 if (!pool_md) {
4086 ti->error = "Couldn't get pool mapped device";
4087 r = -EINVAL;
4088 goto bad_common;
4089 }
4090
4091 tc->pool = __pool_table_lookup(pool_md);
4092 if (!tc->pool) {
4093 ti->error = "Couldn't find pool object";
4094 r = -EINVAL;
4095 goto bad_pool_lookup;
4096 }
4097 __pool_inc(tc->pool);
4098
4099 if (get_pool_mode(tc->pool) == PM_FAIL) {
4100 ti->error = "Couldn't open thin device, Pool is in fail mode";
4101 r = -EINVAL;
4102 goto bad_pool;
4103 }
4104
4105 r = dm_pool_open_thin_device(tc->pool->pmd, tc->dev_id, &tc->td);
4106 if (r) {
4107 ti->error = "Couldn't open thin internal device";
4108 goto bad_pool;
4109 }
4110
4111 r = dm_set_target_max_io_len(ti, tc->pool->sectors_per_block);
4112 if (r)
4113 goto bad;
4114
4115 ti->num_flush_bios = 1;
4116 ti->flush_supported = true;
4117 ti->per_io_data_size = sizeof(struct dm_thin_endio_hook);
4118
4119
4120 if (tc->pool->pf.discard_enabled) {
4121 ti->discards_supported = true;
4122 ti->num_discard_bios = 1;
4123 ti->split_discard_bios = false;
4124 }
4125
4126 mutex_unlock(&dm_thin_pool_table.mutex);
4127
4128 spin_lock_irqsave(&tc->pool->lock, flags);
4129 if (tc->pool->suspended) {
4130 spin_unlock_irqrestore(&tc->pool->lock, flags);
4131 mutex_lock(&dm_thin_pool_table.mutex);
4132 ti->error = "Unable to activate thin device while pool is suspended";
4133 r = -EINVAL;
4134 goto bad;
4135 }
4136 atomic_set(&tc->refcount, 1);
4137 init_completion(&tc->can_destroy);
4138 list_add_tail_rcu(&tc->list, &tc->pool->active_thins);
4139 spin_unlock_irqrestore(&tc->pool->lock, flags);
4140
4141
4142
4143
4144
4145
4146 synchronize_rcu();
4147
4148 dm_put(pool_md);
4149
4150 return 0;
4151
4152bad:
4153 dm_pool_close_thin_device(tc->td);
4154bad_pool:
4155 __pool_dec(tc->pool);
4156bad_pool_lookup:
4157 dm_put(pool_md);
4158bad_common:
4159 dm_put_device(ti, tc->pool_dev);
4160bad_pool_dev:
4161 if (tc->origin_dev)
4162 dm_put_device(ti, tc->origin_dev);
4163bad_origin_dev:
4164 kfree(tc);
4165out_unlock:
4166 mutex_unlock(&dm_thin_pool_table.mutex);
4167
4168 return r;
4169}
4170
4171static int thin_map(struct dm_target *ti, struct bio *bio)
4172{
4173 bio->bi_iter.bi_sector = dm_target_offset(ti, bio->bi_iter.bi_sector);
4174
4175 return thin_bio_map(ti, bio);
4176}
4177
4178static int thin_endio(struct dm_target *ti, struct bio *bio,
4179 blk_status_t *err)
4180{
4181 unsigned long flags;
4182 struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook));
4183 struct list_head work;
4184 struct dm_thin_new_mapping *m, *tmp;
4185 struct pool *pool = h->tc->pool;
4186
4187 if (h->shared_read_entry) {
4188 INIT_LIST_HEAD(&work);
4189 dm_deferred_entry_dec(h->shared_read_entry, &work);
4190
4191 spin_lock_irqsave(&pool->lock, flags);
4192 list_for_each_entry_safe(m, tmp, &work, list) {
4193 list_del(&m->list);
4194 __complete_mapping_preparation(m);
4195 }
4196 spin_unlock_irqrestore(&pool->lock, flags);
4197 }
4198
4199 if (h->all_io_entry) {
4200 INIT_LIST_HEAD(&work);
4201 dm_deferred_entry_dec(h->all_io_entry, &work);
4202 if (!list_empty(&work)) {
4203 spin_lock_irqsave(&pool->lock, flags);
4204 list_for_each_entry_safe(m, tmp, &work, list)
4205 list_add_tail(&m->list, &pool->prepared_discards);
4206 spin_unlock_irqrestore(&pool->lock, flags);
4207 wake_worker(pool);
4208 }
4209 }
4210
4211 if (h->cell)
4212 cell_defer_no_holder(h->tc, h->cell);
4213
4214 return DM_ENDIO_DONE;
4215}
4216
4217static void thin_presuspend(struct dm_target *ti)
4218{
4219 struct thin_c *tc = ti->private;
4220
4221 if (dm_noflush_suspending(ti))
4222 noflush_work(tc, do_noflush_start);
4223}
4224
4225static void thin_postsuspend(struct dm_target *ti)
4226{
4227 struct thin_c *tc = ti->private;
4228
4229
4230
4231
4232
4233 noflush_work(tc, do_noflush_stop);
4234}
4235
4236static int thin_preresume(struct dm_target *ti)
4237{
4238 struct thin_c *tc = ti->private;
4239
4240 if (tc->origin_dev)
4241 tc->origin_size = get_dev_size(tc->origin_dev->bdev);
4242
4243 return 0;
4244}
4245
4246
4247
4248
4249static void thin_status(struct dm_target *ti, status_type_t type,
4250 unsigned status_flags, char *result, unsigned maxlen)
4251{
4252 int r;
4253 ssize_t sz = 0;
4254 dm_block_t mapped, highest;
4255 char buf[BDEVNAME_SIZE];
4256 struct thin_c *tc = ti->private;
4257
4258 if (get_pool_mode(tc->pool) == PM_FAIL) {
4259 DMEMIT("Fail");
4260 return;
4261 }
4262
4263 if (!tc->td)
4264 DMEMIT("-");
4265 else {
4266 switch (type) {
4267 case STATUSTYPE_INFO:
4268 r = dm_thin_get_mapped_count(tc->td, &mapped);
4269 if (r) {
4270 DMERR("dm_thin_get_mapped_count returned %d", r);
4271 goto err;
4272 }
4273
4274 r = dm_thin_get_highest_mapped_block(tc->td, &highest);
4275 if (r < 0) {
4276 DMERR("dm_thin_get_highest_mapped_block returned %d", r);
4277 goto err;
4278 }
4279
4280 DMEMIT("%llu ", mapped * tc->pool->sectors_per_block);
4281 if (r)
4282 DMEMIT("%llu", ((highest + 1) *
4283 tc->pool->sectors_per_block) - 1);
4284 else
4285 DMEMIT("-");
4286 break;
4287
4288 case STATUSTYPE_TABLE:
4289 DMEMIT("%s %lu",
4290 format_dev_t(buf, tc->pool_dev->bdev->bd_dev),
4291 (unsigned long) tc->dev_id);
4292 if (tc->origin_dev)
4293 DMEMIT(" %s", format_dev_t(buf, tc->origin_dev->bdev->bd_dev));
4294 break;
4295 }
4296 }
4297
4298 return;
4299
4300err:
4301 DMEMIT("Error");
4302}
4303
4304static int thin_iterate_devices(struct dm_target *ti,
4305 iterate_devices_callout_fn fn, void *data)
4306{
4307 sector_t blocks;
4308 struct thin_c *tc = ti->private;
4309 struct pool *pool = tc->pool;
4310
4311
4312
4313
4314
4315 if (!pool->ti)
4316 return 0;
4317
4318 blocks = pool->ti->len;
4319 (void) sector_div(blocks, pool->sectors_per_block);
4320 if (blocks)
4321 return fn(ti, tc->pool_dev, 0, pool->sectors_per_block * blocks, data);
4322
4323 return 0;
4324}
4325
4326static void thin_io_hints(struct dm_target *ti, struct queue_limits *limits)
4327{
4328 struct thin_c *tc = ti->private;
4329 struct pool *pool = tc->pool;
4330
4331 if (!pool->pf.discard_enabled)
4332 return;
4333
4334 limits->discard_granularity = pool->sectors_per_block << SECTOR_SHIFT;
4335 limits->max_discard_sectors = 2048 * 1024 * 16;
4336}
4337
4338static struct target_type thin_target = {
4339 .name = "thin",
4340 .version = {1, 19, 0},
4341 .module = THIS_MODULE,
4342 .ctr = thin_ctr,
4343 .dtr = thin_dtr,
4344 .map = thin_map,
4345 .end_io = thin_endio,
4346 .preresume = thin_preresume,
4347 .presuspend = thin_presuspend,
4348 .postsuspend = thin_postsuspend,
4349 .status = thin_status,
4350 .iterate_devices = thin_iterate_devices,
4351 .io_hints = thin_io_hints,
4352};
4353
4354
4355
4356static int __init dm_thin_init(void)
4357{
4358 int r;
4359
4360 pool_table_init();
4361
4362 r = dm_register_target(&thin_target);
4363 if (r)
4364 return r;
4365
4366 r = dm_register_target(&pool_target);
4367 if (r)
4368 goto bad_pool_target;
4369
4370 r = -ENOMEM;
4371
4372 _new_mapping_cache = KMEM_CACHE(dm_thin_new_mapping, 0);
4373 if (!_new_mapping_cache)
4374 goto bad_new_mapping_cache;
4375
4376 return 0;
4377
4378bad_new_mapping_cache:
4379 dm_unregister_target(&pool_target);
4380bad_pool_target:
4381 dm_unregister_target(&thin_target);
4382
4383 return r;
4384}
4385
4386static void dm_thin_exit(void)
4387{
4388 dm_unregister_target(&thin_target);
4389 dm_unregister_target(&pool_target);
4390
4391 kmem_cache_destroy(_new_mapping_cache);
4392}
4393
4394module_init(dm_thin_init);
4395module_exit(dm_thin_exit);
4396
4397module_param_named(no_space_timeout, no_space_timeout_secs, uint, S_IRUGO | S_IWUSR);
4398MODULE_PARM_DESC(no_space_timeout, "Out of data space queue IO timeout in seconds");
4399
4400MODULE_DESCRIPTION(DM_NAME " thin provisioning target");
4401MODULE_AUTHOR("Joe Thornber <dm-devel@redhat.com>");
4402MODULE_LICENSE("GPL");
4403