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1/*
2 * Copyright (C) 2011 Red Hat, Inc.
3 *
4 * This file is released under the GPL.
5 */
6
7#include "dm-space-map-common.h"
8#include "dm-transaction-manager.h"
9#include "dm-btree-internal.h"
10#include "dm-persistent-data-internal.h"
11
12#include <linux/bitops.h>
13#include <linux/device-mapper.h>
14
15#define DM_MSG_PREFIX "space map common"
16
17/*----------------------------------------------------------------*/
18
19/*
20 * Index validator.
21 */
22#define INDEX_CSUM_XOR 160478
23
24static void index_prepare_for_write(struct dm_block_validator *v,
25 struct dm_block *b,
26 size_t block_size)
27{
28 struct disk_metadata_index *mi_le = dm_block_data(b);
29
30 mi_le->blocknr = cpu_to_le64(dm_block_location(b));
31 mi_le->csum = cpu_to_le32(dm_bm_checksum(&mi_le->padding,
32 block_size - sizeof(__le32),
33 INDEX_CSUM_XOR));
34}
35
36static int index_check(struct dm_block_validator *v,
37 struct dm_block *b,
38 size_t block_size)
39{
40 struct disk_metadata_index *mi_le = dm_block_data(b);
41 __le32 csum_disk;
42
43 if (dm_block_location(b) != le64_to_cpu(mi_le->blocknr)) {
44 DMERR_LIMIT("index_check failed: blocknr %llu != wanted %llu",
45 le64_to_cpu(mi_le->blocknr), dm_block_location(b));
46 return -ENOTBLK;
47 }
48
49 csum_disk = cpu_to_le32(dm_bm_checksum(&mi_le->padding,
50 block_size - sizeof(__le32),
51 INDEX_CSUM_XOR));
52 if (csum_disk != mi_le->csum) {
53 DMERR_LIMIT("index_check failed: csum %u != wanted %u",
54 le32_to_cpu(csum_disk), le32_to_cpu(mi_le->csum));
55 return -EILSEQ;
56 }
57
58 return 0;
59}
60
61static struct dm_block_validator index_validator = {
62 .name = "index",
63 .prepare_for_write = index_prepare_for_write,
64 .check = index_check
65};
66
67/*----------------------------------------------------------------*/
68
69/*
70 * Bitmap validator
71 */
72#define BITMAP_CSUM_XOR 240779
73
74static void dm_bitmap_prepare_for_write(struct dm_block_validator *v,
75 struct dm_block *b,
76 size_t block_size)
77{
78 struct disk_bitmap_header *disk_header = dm_block_data(b);
79
80 disk_header->blocknr = cpu_to_le64(dm_block_location(b));
81 disk_header->csum = cpu_to_le32(dm_bm_checksum(&disk_header->not_used,
82 block_size - sizeof(__le32),
83 BITMAP_CSUM_XOR));
84}
85
86static int dm_bitmap_check(struct dm_block_validator *v,
87 struct dm_block *b,
88 size_t block_size)
89{
90 struct disk_bitmap_header *disk_header = dm_block_data(b);
91 __le32 csum_disk;
92
93 if (dm_block_location(b) != le64_to_cpu(disk_header->blocknr)) {
94 DMERR_LIMIT("bitmap check failed: blocknr %llu != wanted %llu",
95 le64_to_cpu(disk_header->blocknr), dm_block_location(b));
96 return -ENOTBLK;
97 }
98
99 csum_disk = cpu_to_le32(dm_bm_checksum(&disk_header->not_used,
100 block_size - sizeof(__le32),
101 BITMAP_CSUM_XOR));
102 if (csum_disk != disk_header->csum) {
103 DMERR_LIMIT("bitmap check failed: csum %u != wanted %u",
104 le32_to_cpu(csum_disk), le32_to_cpu(disk_header->csum));
105 return -EILSEQ;
106 }
107
108 return 0;
109}
110
111static struct dm_block_validator dm_sm_bitmap_validator = {
112 .name = "sm_bitmap",
113 .prepare_for_write = dm_bitmap_prepare_for_write,
114 .check = dm_bitmap_check,
115};
116
117/*----------------------------------------------------------------*/
118
119#define ENTRIES_PER_WORD 32
120#define ENTRIES_SHIFT 5
121
122static void *dm_bitmap_data(struct dm_block *b)
123{
124 return dm_block_data(b) + sizeof(struct disk_bitmap_header);
125}
126
127#define WORD_MASK_HIGH 0xAAAAAAAAAAAAAAAAULL
128
129static unsigned dm_bitmap_word_used(void *addr, unsigned b)
130{
131 __le64 *words_le = addr;
132 __le64 *w_le = words_le + (b >> ENTRIES_SHIFT);
133
134 uint64_t bits = le64_to_cpu(*w_le);
135 uint64_t mask = (bits + WORD_MASK_HIGH + 1) & WORD_MASK_HIGH;
136
137 return !(~bits & mask);
138}
139
140static unsigned sm_lookup_bitmap(void *addr, unsigned b)
141{
142 __le64 *words_le = addr;
143 __le64 *w_le = words_le + (b >> ENTRIES_SHIFT);
144 unsigned hi, lo;
145
146 b = (b & (ENTRIES_PER_WORD - 1)) << 1;
147 hi = !!test_bit_le(b, (void *) w_le);
148 lo = !!test_bit_le(b + 1, (void *) w_le);
149 return (hi << 1) | lo;
150}
151
152static void sm_set_bitmap(void *addr, unsigned b, unsigned val)
153{
154 __le64 *words_le = addr;
155 __le64 *w_le = words_le + (b >> ENTRIES_SHIFT);
156
157 b = (b & (ENTRIES_PER_WORD - 1)) << 1;
158
159 if (val & 2)
160 __set_bit_le(b, (void *) w_le);
161 else
162 __clear_bit_le(b, (void *) w_le);
163
164 if (val & 1)
165 __set_bit_le(b + 1, (void *) w_le);
166 else
167 __clear_bit_le(b + 1, (void *) w_le);
168}
169
170static int sm_find_free(void *addr, unsigned begin, unsigned end,
171 unsigned *result)
172{
173 while (begin < end) {
174 if (!(begin & (ENTRIES_PER_WORD - 1)) &&
175 dm_bitmap_word_used(addr, begin)) {
176 begin += ENTRIES_PER_WORD;
177 continue;
178 }
179
180 if (!sm_lookup_bitmap(addr, begin)) {
181 *result = begin;
182 return 0;
183 }
184
185 begin++;
186 }
187
188 return -ENOSPC;
189}
190
191/*----------------------------------------------------------------*/
192
193static int sm_ll_init(struct ll_disk *ll, struct dm_transaction_manager *tm)
194{
195 memset(ll, 0, sizeof(struct ll_disk));
196
197 ll->tm = tm;
198
199 ll->bitmap_info.tm = tm;
200 ll->bitmap_info.levels = 1;
201
202 /*
203 * Because the new bitmap blocks are created via a shadow
204 * operation, the old entry has already had its reference count
205 * decremented and we don't need the btree to do any bookkeeping.
206 */
207 ll->bitmap_info.value_type.size = sizeof(struct disk_index_entry);
208 ll->bitmap_info.value_type.inc = NULL;
209 ll->bitmap_info.value_type.dec = NULL;
210 ll->bitmap_info.value_type.equal = NULL;
211
212 ll->ref_count_info.tm = tm;
213 ll->ref_count_info.levels = 1;
214 ll->ref_count_info.value_type.size = sizeof(uint32_t);
215 ll->ref_count_info.value_type.inc = NULL;
216 ll->ref_count_info.value_type.dec = NULL;
217 ll->ref_count_info.value_type.equal = NULL;
218
219 ll->block_size = dm_bm_block_size(dm_tm_get_bm(tm));
220
221 if (ll->block_size > (1 << 30)) {
222 DMERR("block size too big to hold bitmaps");
223 return -EINVAL;
224 }
225
226 ll->entries_per_block = (ll->block_size - sizeof(struct disk_bitmap_header)) *
227 ENTRIES_PER_BYTE;
228 ll->nr_blocks = 0;
229 ll->bitmap_root = 0;
230 ll->ref_count_root = 0;
231 ll->bitmap_index_changed = false;
232
233 return 0;
234}
235
236int sm_ll_extend(struct ll_disk *ll, dm_block_t extra_blocks)
237{
238 int r;
239 dm_block_t i, nr_blocks, nr_indexes;
240 unsigned old_blocks, blocks;
241
242 nr_blocks = ll->nr_blocks + extra_blocks;
243 old_blocks = dm_sector_div_up(ll->nr_blocks, ll->entries_per_block);
244 blocks = dm_sector_div_up(nr_blocks, ll->entries_per_block);
245
246 nr_indexes = dm_sector_div_up(nr_blocks, ll->entries_per_block);
247 if (nr_indexes > ll->max_entries(ll)) {
248 DMERR("space map too large");
249 return -EINVAL;
250 }
251
252 /*
253 * We need to set this before the dm_tm_new_block() call below.
254 */
255 ll->nr_blocks = nr_blocks;
256 for (i = old_blocks; i < blocks; i++) {
257 struct dm_block *b;
258 struct disk_index_entry idx;
259
260 r = dm_tm_new_block(ll->tm, &dm_sm_bitmap_validator, &b);
261 if (r < 0)
262 return r;
263
264 idx.blocknr = cpu_to_le64(dm_block_location(b));
265
266 dm_tm_unlock(ll->tm, b);
267
268 idx.nr_free = cpu_to_le32(ll->entries_per_block);
269 idx.none_free_before = 0;
270
271 r = ll->save_ie(ll, i, &idx);
272 if (r < 0)
273 return r;
274 }
275
276 return 0;
277}
278
279int sm_ll_lookup_bitmap(struct ll_disk *ll, dm_block_t b, uint32_t *result)
280{
281 int r;
282 dm_block_t index = b;
283 struct disk_index_entry ie_disk;
284 struct dm_block *blk;
285
286 if (b >= ll->nr_blocks) {
287 DMERR_LIMIT("metadata block out of bounds");
288 return -EINVAL;
289 }
290
291 b = do_div(index, ll->entries_per_block);
292 r = ll->load_ie(ll, index, &ie_disk);
293 if (r < 0)
294 return r;
295
296 r = dm_tm_read_lock(ll->tm, le64_to_cpu(ie_disk.blocknr),
297 &dm_sm_bitmap_validator, &blk);
298 if (r < 0)
299 return r;
300
301 *result = sm_lookup_bitmap(dm_bitmap_data(blk), b);
302
303 dm_tm_unlock(ll->tm, blk);
304
305 return 0;
306}
307
308static int sm_ll_lookup_big_ref_count(struct ll_disk *ll, dm_block_t b,
309 uint32_t *result)
310{
311 __le32 le_rc;
312 int r;
313
314 r = dm_btree_lookup(&ll->ref_count_info, ll->ref_count_root, &b, &le_rc);
315 if (r < 0)
316 return r;
317
318 *result = le32_to_cpu(le_rc);
319
320 return r;
321}
322
323int sm_ll_lookup(struct ll_disk *ll, dm_block_t b, uint32_t *result)
324{
325 int r = sm_ll_lookup_bitmap(ll, b, result);
326
327 if (r)
328 return r;
329
330 if (*result != 3)
331 return r;
332
333 return sm_ll_lookup_big_ref_count(ll, b, result);
334}
335
336int sm_ll_find_free_block(struct ll_disk *ll, dm_block_t begin,
337 dm_block_t end, dm_block_t *result)
338{
339 int r;
340 struct disk_index_entry ie_disk;
341 dm_block_t i, index_begin = begin;
342 dm_block_t index_end = dm_sector_div_up(end, ll->entries_per_block);
343
344 /*
345 * FIXME: Use shifts
346 */
347 begin = do_div(index_begin, ll->entries_per_block);
348 end = do_div(end, ll->entries_per_block);
349 if (end == 0)
350 end = ll->entries_per_block;
351
352 for (i = index_begin; i < index_end; i++, begin = 0) {
353 struct dm_block *blk;
354 unsigned position;
355 uint32_t bit_end;
356
357 r = ll->load_ie(ll, i, &ie_disk);
358 if (r < 0)
359 return r;
360
361 if (le32_to_cpu(ie_disk.nr_free) == 0)
362 continue;
363
364 r = dm_tm_read_lock(ll->tm, le64_to_cpu(ie_disk.blocknr),
365 &dm_sm_bitmap_validator, &blk);
366 if (r < 0)
367 return r;
368
369 bit_end = (i == index_end - 1) ? end : ll->entries_per_block;
370
371 r = sm_find_free(dm_bitmap_data(blk),
372 max_t(unsigned, begin, le32_to_cpu(ie_disk.none_free_before)),
373 bit_end, &position);
374 if (r == -ENOSPC) {
375 /*
376 * This might happen because we started searching
377 * part way through the bitmap.
378 */
379 dm_tm_unlock(ll->tm, blk);
380 continue;
381 }
382
383 dm_tm_unlock(ll->tm, blk);
384
385 *result = i * ll->entries_per_block + (dm_block_t) position;
386 return 0;
387 }
388
389 return -ENOSPC;
390}
391
392int sm_ll_find_common_free_block(struct ll_disk *old_ll, struct ll_disk *new_ll,
393 dm_block_t begin, dm_block_t end, dm_block_t *b)
394{
395 int r;
396 uint32_t count;
397
398 do {
399 r = sm_ll_find_free_block(new_ll, begin, new_ll->nr_blocks, b);
400 if (r)
401 break;
402
403 /* double check this block wasn't used in the old transaction */
404 if (*b >= old_ll->nr_blocks)
405 count = 0;
406 else {
407 r = sm_ll_lookup(old_ll, *b, &count);
408 if (r)
409 break;
410
411 if (count)
412 begin = *b + 1;
413 }
414 } while (count);
415
416 return r;
417}
418
419/*----------------------------------------------------------------*/
420
421int sm_ll_insert(struct ll_disk *ll, dm_block_t b,
422 uint32_t ref_count, int32_t *nr_allocations)
423{
424 int r;
425 uint32_t bit, old;
426 struct dm_block *nb;
427 dm_block_t index = b;
428 struct disk_index_entry ie_disk;
429 void *bm_le;
430 int inc;
431
432 bit = do_div(index, ll->entries_per_block);
433 r = ll->load_ie(ll, index, &ie_disk);
434 if (r < 0)
435 return r;
436
437 r = dm_tm_shadow_block(ll->tm, le64_to_cpu(ie_disk.blocknr),
438 &dm_sm_bitmap_validator, &nb, &inc);
439 if (r < 0) {
440 DMERR("dm_tm_shadow_block() failed");
441 return r;
442 }
443 ie_disk.blocknr = cpu_to_le64(dm_block_location(nb));
444 bm_le = dm_bitmap_data(nb);
445
446 old = sm_lookup_bitmap(bm_le, bit);
447 if (old > 2) {
448 r = sm_ll_lookup_big_ref_count(ll, b, &old);
449 if (r < 0) {
450 dm_tm_unlock(ll->tm, nb);
451 return r;
452 }
453 }
454
455 if (r) {
456 dm_tm_unlock(ll->tm, nb);
457 return r;
458 }
459
460 if (ref_count <= 2) {
461 sm_set_bitmap(bm_le, bit, ref_count);
462 dm_tm_unlock(ll->tm, nb);
463
464 if (old > 2) {
465 r = dm_btree_remove(&ll->ref_count_info,
466 ll->ref_count_root,
467 &b, &ll->ref_count_root);
468 if (r)
469 return r;
470 }
471
472 } else {
473 __le32 le_rc = cpu_to_le32(ref_count);
474
475 sm_set_bitmap(bm_le, bit, 3);
476 dm_tm_unlock(ll->tm, nb);
477
478 __dm_bless_for_disk(&le_rc);
479 r = dm_btree_insert(&ll->ref_count_info, ll->ref_count_root,
480 &b, &le_rc, &ll->ref_count_root);
481 if (r < 0) {
482 DMERR("ref count insert failed");
483 return r;
484 }
485 }
486
487 if (ref_count && !old) {
488 *nr_allocations = 1;
489 ll->nr_allocated++;
490 le32_add_cpu(&ie_disk.nr_free, -1);
491 if (le32_to_cpu(ie_disk.none_free_before) == bit)
492 ie_disk.none_free_before = cpu_to_le32(bit + 1);
493
494 } else if (old && !ref_count) {
495 *nr_allocations = -1;
496 ll->nr_allocated--;
497 le32_add_cpu(&ie_disk.nr_free, 1);
498 ie_disk.none_free_before = cpu_to_le32(min(le32_to_cpu(ie_disk.none_free_before), bit));
499 } else
500 *nr_allocations = 0;
501
502 return ll->save_ie(ll, index, &ie_disk);
503}
504
505/*----------------------------------------------------------------*/
506
507/*
508 * Holds useful intermediate results for the range based inc and dec
509 * operations.
510 */
511struct inc_context {
512 struct disk_index_entry ie_disk;
513 struct dm_block *bitmap_block;
514 void *bitmap;
515
516 struct dm_block *overflow_leaf;
517};
518
519static inline void init_inc_context(struct inc_context *ic)
520{
521 ic->bitmap_block = NULL;
522 ic->bitmap = NULL;
523 ic->overflow_leaf = NULL;
524}
525
526static inline void exit_inc_context(struct ll_disk *ll, struct inc_context *ic)
527{
528 if (ic->bitmap_block)
529 dm_tm_unlock(ll->tm, ic->bitmap_block);
530 if (ic->overflow_leaf)
531 dm_tm_unlock(ll->tm, ic->overflow_leaf);
532}
533
534static inline void reset_inc_context(struct ll_disk *ll, struct inc_context *ic)
535{
536 exit_inc_context(ll, ic);
537 init_inc_context(ic);
538}
539
540/*
541 * Confirms a btree node contains a particular key at an index.
542 */
543static bool contains_key(struct btree_node *n, uint64_t key, int index)
544{
545 return index >= 0 &&
546 index < le32_to_cpu(n->header.nr_entries) &&
547 le64_to_cpu(n->keys[index]) == key;
548}
549
550static int __sm_ll_inc_overflow(struct ll_disk *ll, dm_block_t b, struct inc_context *ic)
551{
552 int r;
553 int index;
554 struct btree_node *n;
555 __le32 *v_ptr;
556 uint32_t rc;
557
558 /*
559 * bitmap_block needs to be unlocked because getting the
560 * overflow_leaf may need to allocate, and thus use the space map.
561 */
562 reset_inc_context(ll, ic);
563
564 r = btree_get_overwrite_leaf(&ll->ref_count_info, ll->ref_count_root,
565 b, &index, &ll->ref_count_root, &ic->overflow_leaf);
566 if (r < 0)
567 return r;
568
569 n = dm_block_data(ic->overflow_leaf);
570
571 if (!contains_key(n, b, index)) {
572 DMERR("overflow btree is missing an entry");
573 return -EINVAL;
574 }
575
576 v_ptr = value_ptr(n, index);
577 rc = le32_to_cpu(*v_ptr) + 1;
578 *v_ptr = cpu_to_le32(rc);
579
580 return 0;
581}
582
583static int sm_ll_inc_overflow(struct ll_disk *ll, dm_block_t b, struct inc_context *ic)
584{
585 int index;
586 struct btree_node *n;
587 __le32 *v_ptr;
588 uint32_t rc;
589
590 /*
591 * Do we already have the correct overflow leaf?
592 */
593 if (ic->overflow_leaf) {
594 n = dm_block_data(ic->overflow_leaf);
595 index = lower_bound(n, b);
596 if (contains_key(n, b, index)) {
597 v_ptr = value_ptr(n, index);
598 rc = le32_to_cpu(*v_ptr) + 1;
599 *v_ptr = cpu_to_le32(rc);
600
601 return 0;
602 }
603 }
604
605 return __sm_ll_inc_overflow(ll, b, ic);
606}
607
608static inline int shadow_bitmap(struct ll_disk *ll, struct inc_context *ic)
609{
610 int r, inc;
611 r = dm_tm_shadow_block(ll->tm, le64_to_cpu(ic->ie_disk.blocknr),
612 &dm_sm_bitmap_validator, &ic->bitmap_block, &inc);
613 if (r < 0) {
614 DMERR("dm_tm_shadow_block() failed");
615 return r;
616 }
617 ic->ie_disk.blocknr = cpu_to_le64(dm_block_location(ic->bitmap_block));
618 ic->bitmap = dm_bitmap_data(ic->bitmap_block);
619 return 0;
620}
621
622/*
623 * Once shadow_bitmap has been called, which always happens at the start of inc/dec,
624 * we can reopen the bitmap with a simple write lock, rather than re calling
625 * dm_tm_shadow_block().
626 */
627static inline int ensure_bitmap(struct ll_disk *ll, struct inc_context *ic)
628{
629 if (!ic->bitmap_block) {
630 int r = dm_bm_write_lock(dm_tm_get_bm(ll->tm), le64_to_cpu(ic->ie_disk.blocknr),
631 &dm_sm_bitmap_validator, &ic->bitmap_block);
632 if (r) {
633 DMERR("unable to re-get write lock for bitmap");
634 return r;
635 }
636 ic->bitmap = dm_bitmap_data(ic->bitmap_block);
637 }
638
639 return 0;
640}
641
642/*
643 * Loops round incrementing entries in a single bitmap.
644 */
645static inline int sm_ll_inc_bitmap(struct ll_disk *ll, dm_block_t b,
646 uint32_t bit, uint32_t bit_end,
647 int32_t *nr_allocations, dm_block_t *new_b,
648 struct inc_context *ic)
649{
650 int r;
651 __le32 le_rc;
652 uint32_t old;
653
654 for (; bit != bit_end; bit++, b++) {
655 /*
656 * We only need to drop the bitmap if we need to find a new btree
657 * leaf for the overflow. So if it was dropped last iteration,
658 * we now re-get it.
659 */
660 r = ensure_bitmap(ll, ic);
661 if (r)
662 return r;
663
664 old = sm_lookup_bitmap(ic->bitmap, bit);
665 switch (old) {
666 case 0:
667 /* inc bitmap, adjust nr_allocated */
668 sm_set_bitmap(ic->bitmap, bit, 1);
669 (*nr_allocations)++;
670 ll->nr_allocated++;
671 le32_add_cpu(&ic->ie_disk.nr_free, -1);
672 if (le32_to_cpu(ic->ie_disk.none_free_before) == bit)
673 ic->ie_disk.none_free_before = cpu_to_le32(bit + 1);
674 break;
675
676 case 1:
677 /* inc bitmap */
678 sm_set_bitmap(ic->bitmap, bit, 2);
679 break;
680
681 case 2:
682 /* inc bitmap and insert into overflow */
683 sm_set_bitmap(ic->bitmap, bit, 3);
684 reset_inc_context(ll, ic);
685
686 le_rc = cpu_to_le32(3);
687 __dm_bless_for_disk(&le_rc);
688 r = dm_btree_insert(&ll->ref_count_info, ll->ref_count_root,
689 &b, &le_rc, &ll->ref_count_root);
690 if (r < 0) {
691 DMERR("ref count insert failed");
692 return r;
693 }
694 break;
695
696 default:
697 /*
698 * inc within the overflow tree only.
699 */
700 r = sm_ll_inc_overflow(ll, b, ic);
701 if (r < 0)
702 return r;
703 }
704 }
705
706 *new_b = b;
707 return 0;
708}
709
710/*
711 * Finds a bitmap that contains entries in the block range, and increments
712 * them.
713 */
714static int __sm_ll_inc(struct ll_disk *ll, dm_block_t b, dm_block_t e,
715 int32_t *nr_allocations, dm_block_t *new_b)
716{
717 int r;
718 struct inc_context ic;
719 uint32_t bit, bit_end;
720 dm_block_t index = b;
721
722 init_inc_context(&ic);
723
724 bit = do_div(index, ll->entries_per_block);
725 r = ll->load_ie(ll, index, &ic.ie_disk);
726 if (r < 0)
727 return r;
728
729 r = shadow_bitmap(ll, &ic);
730 if (r)
731 return r;
732
733 bit_end = min(bit + (e - b), (dm_block_t) ll->entries_per_block);
734 r = sm_ll_inc_bitmap(ll, b, bit, bit_end, nr_allocations, new_b, &ic);
735
736 exit_inc_context(ll, &ic);
737
738 if (r)
739 return r;
740
741 return ll->save_ie(ll, index, &ic.ie_disk);
742}
743
744int sm_ll_inc(struct ll_disk *ll, dm_block_t b, dm_block_t e,
745 int32_t *nr_allocations)
746{
747 *nr_allocations = 0;
748 while (b != e) {
749 int r = __sm_ll_inc(ll, b, e, nr_allocations, &b);
750 if (r)
751 return r;
752 }
753
754 return 0;
755}
756
757/*----------------------------------------------------------------*/
758
759static int __sm_ll_del_overflow(struct ll_disk *ll, dm_block_t b,
760 struct inc_context *ic)
761{
762 reset_inc_context(ll, ic);
763 return dm_btree_remove(&ll->ref_count_info, ll->ref_count_root,
764 &b, &ll->ref_count_root);
765}
766
767static int __sm_ll_dec_overflow(struct ll_disk *ll, dm_block_t b,
768 struct inc_context *ic, uint32_t *old_rc)
769{
770 int r;
771 int index = -1;
772 struct btree_node *n;
773 __le32 *v_ptr;
774 uint32_t rc;
775
776 reset_inc_context(ll, ic);
777 r = btree_get_overwrite_leaf(&ll->ref_count_info, ll->ref_count_root,
778 b, &index, &ll->ref_count_root, &ic->overflow_leaf);
779 if (r < 0)
780 return r;
781
782 n = dm_block_data(ic->overflow_leaf);
783
784 if (!contains_key(n, b, index)) {
785 DMERR("overflow btree is missing an entry");
786 return -EINVAL;
787 }
788
789 v_ptr = value_ptr(n, index);
790 rc = le32_to_cpu(*v_ptr);
791 *old_rc = rc;
792
793 if (rc == 3) {
794 return __sm_ll_del_overflow(ll, b, ic);
795 } else {
796 rc--;
797 *v_ptr = cpu_to_le32(rc);
798 return 0;
799 }
800}
801
802static int sm_ll_dec_overflow(struct ll_disk *ll, dm_block_t b,
803 struct inc_context *ic, uint32_t *old_rc)
804{
805 /*
806 * Do we already have the correct overflow leaf?
807 */
808 if (ic->overflow_leaf) {
809 int index;
810 struct btree_node *n;
811 __le32 *v_ptr;
812 uint32_t rc;
813
814 n = dm_block_data(ic->overflow_leaf);
815 index = lower_bound(n, b);
816 if (contains_key(n, b, index)) {
817 v_ptr = value_ptr(n, index);
818 rc = le32_to_cpu(*v_ptr);
819 *old_rc = rc;
820
821 if (rc > 3) {
822 rc--;
823 *v_ptr = cpu_to_le32(rc);
824 return 0;
825 } else {
826 return __sm_ll_del_overflow(ll, b, ic);
827 }
828
829 }
830 }
831
832 return __sm_ll_dec_overflow(ll, b, ic, old_rc);
833}
834
835/*
836 * Loops round incrementing entries in a single bitmap.
837 */
838static inline int sm_ll_dec_bitmap(struct ll_disk *ll, dm_block_t b,
839 uint32_t bit, uint32_t bit_end,
840 struct inc_context *ic,
841 int32_t *nr_allocations, dm_block_t *new_b)
842{
843 int r;
844 uint32_t old;
845
846 for (; bit != bit_end; bit++, b++) {
847 /*
848 * We only need to drop the bitmap if we need to find a new btree
849 * leaf for the overflow. So if it was dropped last iteration,
850 * we now re-get it.
851 */
852 r = ensure_bitmap(ll, ic);
853 if (r)
854 return r;
855
856 old = sm_lookup_bitmap(ic->bitmap, bit);
857 switch (old) {
858 case 0:
859 DMERR("unable to decrement block");
860 return -EINVAL;
861
862 case 1:
863 /* dec bitmap */
864 sm_set_bitmap(ic->bitmap, bit, 0);
865 (*nr_allocations)--;
866 ll->nr_allocated--;
867 le32_add_cpu(&ic->ie_disk.nr_free, 1);
868 ic->ie_disk.none_free_before =
869 cpu_to_le32(min(le32_to_cpu(ic->ie_disk.none_free_before), bit));
870 break;
871
872 case 2:
873 /* dec bitmap and insert into overflow */
874 sm_set_bitmap(ic->bitmap, bit, 1);
875 break;
876
877 case 3:
878 r = sm_ll_dec_overflow(ll, b, ic, &old);
879 if (r < 0)
880 return r;
881
882 if (old == 3) {
883 r = ensure_bitmap(ll, ic);
884 if (r)
885 return r;
886
887 sm_set_bitmap(ic->bitmap, bit, 2);
888 }
889 break;
890 }
891 }
892
893 *new_b = b;
894 return 0;
895}
896
897static int __sm_ll_dec(struct ll_disk *ll, dm_block_t b, dm_block_t e,
898 int32_t *nr_allocations, dm_block_t *new_b)
899{
900 int r;
901 uint32_t bit, bit_end;
902 struct inc_context ic;
903 dm_block_t index = b;
904
905 init_inc_context(&ic);
906
907 bit = do_div(index, ll->entries_per_block);
908 r = ll->load_ie(ll, index, &ic.ie_disk);
909 if (r < 0)
910 return r;
911
912 r = shadow_bitmap(ll, &ic);
913 if (r)
914 return r;
915
916 bit_end = min(bit + (e - b), (dm_block_t) ll->entries_per_block);
917 r = sm_ll_dec_bitmap(ll, b, bit, bit_end, &ic, nr_allocations, new_b);
918 exit_inc_context(ll, &ic);
919
920 if (r)
921 return r;
922
923 return ll->save_ie(ll, index, &ic.ie_disk);
924}
925
926int sm_ll_dec(struct ll_disk *ll, dm_block_t b, dm_block_t e,
927 int32_t *nr_allocations)
928{
929 *nr_allocations = 0;
930 while (b != e) {
931 int r = __sm_ll_dec(ll, b, e, nr_allocations, &b);
932 if (r)
933 return r;
934 }
935
936 return 0;
937}
938
939/*----------------------------------------------------------------*/
940
941int sm_ll_commit(struct ll_disk *ll)
942{
943 int r = 0;
944
945 if (ll->bitmap_index_changed) {
946 r = ll->commit(ll);
947 if (!r)
948 ll->bitmap_index_changed = false;
949 }
950
951 return r;
952}
953
954/*----------------------------------------------------------------*/
955
956static int metadata_ll_load_ie(struct ll_disk *ll, dm_block_t index,
957 struct disk_index_entry *ie)
958{
959 memcpy(ie, ll->mi_le.index + index, sizeof(*ie));
960 return 0;
961}
962
963static int metadata_ll_save_ie(struct ll_disk *ll, dm_block_t index,
964 struct disk_index_entry *ie)
965{
966 ll->bitmap_index_changed = true;
967 memcpy(ll->mi_le.index + index, ie, sizeof(*ie));
968 return 0;
969}
970
971static int metadata_ll_init_index(struct ll_disk *ll)
972{
973 int r;
974 struct dm_block *b;
975
976 r = dm_tm_new_block(ll->tm, &index_validator, &b);
977 if (r < 0)
978 return r;
979
980 ll->bitmap_root = dm_block_location(b);
981
982 dm_tm_unlock(ll->tm, b);
983
984 return 0;
985}
986
987static int metadata_ll_open(struct ll_disk *ll)
988{
989 int r;
990 struct dm_block *block;
991
992 r = dm_tm_read_lock(ll->tm, ll->bitmap_root,
993 &index_validator, &block);
994 if (r)
995 return r;
996
997 memcpy(&ll->mi_le, dm_block_data(block), sizeof(ll->mi_le));
998 dm_tm_unlock(ll->tm, block);
999
1000 return 0;
1001}
1002
1003static dm_block_t metadata_ll_max_entries(struct ll_disk *ll)
1004{
1005 return MAX_METADATA_BITMAPS;
1006}
1007
1008static int metadata_ll_commit(struct ll_disk *ll)
1009{
1010 int r, inc;
1011 struct dm_block *b;
1012
1013 r = dm_tm_shadow_block(ll->tm, ll->bitmap_root, &index_validator, &b, &inc);
1014 if (r)
1015 return r;
1016
1017 memcpy(dm_block_data(b), &ll->mi_le, sizeof(ll->mi_le));
1018 ll->bitmap_root = dm_block_location(b);
1019
1020 dm_tm_unlock(ll->tm, b);
1021
1022 return 0;
1023}
1024
1025int sm_ll_new_metadata(struct ll_disk *ll, struct dm_transaction_manager *tm)
1026{
1027 int r;
1028
1029 r = sm_ll_init(ll, tm);
1030 if (r < 0)
1031 return r;
1032
1033 ll->load_ie = metadata_ll_load_ie;
1034 ll->save_ie = metadata_ll_save_ie;
1035 ll->init_index = metadata_ll_init_index;
1036 ll->open_index = metadata_ll_open;
1037 ll->max_entries = metadata_ll_max_entries;
1038 ll->commit = metadata_ll_commit;
1039
1040 ll->nr_blocks = 0;
1041 ll->nr_allocated = 0;
1042
1043 r = ll->init_index(ll);
1044 if (r < 0)
1045 return r;
1046
1047 r = dm_btree_empty(&ll->ref_count_info, &ll->ref_count_root);
1048 if (r < 0)
1049 return r;
1050
1051 return 0;
1052}
1053
1054int sm_ll_open_metadata(struct ll_disk *ll, struct dm_transaction_manager *tm,
1055 void *root_le, size_t len)
1056{
1057 int r;
1058 struct disk_sm_root smr;
1059
1060 if (len < sizeof(struct disk_sm_root)) {
1061 DMERR("sm_metadata root too small");
1062 return -ENOMEM;
1063 }
1064
1065 /*
1066 * We don't know the alignment of the root_le buffer, so need to
1067 * copy into a new structure.
1068 */
1069 memcpy(&smr, root_le, sizeof(smr));
1070
1071 r = sm_ll_init(ll, tm);
1072 if (r < 0)
1073 return r;
1074
1075 ll->load_ie = metadata_ll_load_ie;
1076 ll->save_ie = metadata_ll_save_ie;
1077 ll->init_index = metadata_ll_init_index;
1078 ll->open_index = metadata_ll_open;
1079 ll->max_entries = metadata_ll_max_entries;
1080 ll->commit = metadata_ll_commit;
1081
1082 ll->nr_blocks = le64_to_cpu(smr.nr_blocks);
1083 ll->nr_allocated = le64_to_cpu(smr.nr_allocated);
1084 ll->bitmap_root = le64_to_cpu(smr.bitmap_root);
1085 ll->ref_count_root = le64_to_cpu(smr.ref_count_root);
1086
1087 return ll->open_index(ll);
1088}
1089
1090/*----------------------------------------------------------------*/
1091
1092static inline int ie_cache_writeback(struct ll_disk *ll, struct ie_cache *iec)
1093{
1094 iec->dirty = false;
1095 __dm_bless_for_disk(iec->ie);
1096 return dm_btree_insert(&ll->bitmap_info, ll->bitmap_root,
1097 &iec->index, &iec->ie, &ll->bitmap_root);
1098}
1099
1100static inline unsigned hash_index(dm_block_t index)
1101{
1102 return dm_hash_block(index, IE_CACHE_MASK);
1103}
1104
1105static int disk_ll_load_ie(struct ll_disk *ll, dm_block_t index,
1106 struct disk_index_entry *ie)
1107{
1108 int r;
1109 unsigned h = hash_index(index);
1110 struct ie_cache *iec = ll->ie_cache + h;
1111
1112 if (iec->valid) {
1113 if (iec->index == index) {
1114 memcpy(ie, &iec->ie, sizeof(*ie));
1115 return 0;
1116 }
1117
1118 if (iec->dirty) {
1119 r = ie_cache_writeback(ll, iec);
1120 if (r)
1121 return r;
1122 }
1123 }
1124
1125 r = dm_btree_lookup(&ll->bitmap_info, ll->bitmap_root, &index, ie);
1126 if (!r) {
1127 iec->valid = true;
1128 iec->dirty = false;
1129 iec->index = index;
1130 memcpy(&iec->ie, ie, sizeof(*ie));
1131 }
1132
1133 return r;
1134}
1135
1136static int disk_ll_save_ie(struct ll_disk *ll, dm_block_t index,
1137 struct disk_index_entry *ie)
1138{
1139 int r;
1140 unsigned h = hash_index(index);
1141 struct ie_cache *iec = ll->ie_cache + h;
1142
1143 ll->bitmap_index_changed = true;
1144 if (iec->valid) {
1145 if (iec->index == index) {
1146 memcpy(&iec->ie, ie, sizeof(*ie));
1147 iec->dirty = true;
1148 return 0;
1149 }
1150
1151 if (iec->dirty) {
1152 r = ie_cache_writeback(ll, iec);
1153 if (r)
1154 return r;
1155 }
1156 }
1157
1158 iec->valid = true;
1159 iec->dirty = true;
1160 iec->index = index;
1161 memcpy(&iec->ie, ie, sizeof(*ie));
1162 return 0;
1163}
1164
1165static int disk_ll_init_index(struct ll_disk *ll)
1166{
1167 unsigned i;
1168 for (i = 0; i < IE_CACHE_SIZE; i++) {
1169 struct ie_cache *iec = ll->ie_cache + i;
1170 iec->valid = false;
1171 iec->dirty = false;
1172 }
1173 return dm_btree_empty(&ll->bitmap_info, &ll->bitmap_root);
1174}
1175
1176static int disk_ll_open(struct ll_disk *ll)
1177{
1178 return 0;
1179}
1180
1181static dm_block_t disk_ll_max_entries(struct ll_disk *ll)
1182{
1183 return -1ULL;
1184}
1185
1186static int disk_ll_commit(struct ll_disk *ll)
1187{
1188 int r = 0;
1189 unsigned i;
1190
1191 for (i = 0; i < IE_CACHE_SIZE; i++) {
1192 struct ie_cache *iec = ll->ie_cache + i;
1193 if (iec->valid && iec->dirty)
1194 r = ie_cache_writeback(ll, iec);
1195 }
1196
1197 return r;
1198}
1199
1200int sm_ll_new_disk(struct ll_disk *ll, struct dm_transaction_manager *tm)
1201{
1202 int r;
1203
1204 r = sm_ll_init(ll, tm);
1205 if (r < 0)
1206 return r;
1207
1208 ll->load_ie = disk_ll_load_ie;
1209 ll->save_ie = disk_ll_save_ie;
1210 ll->init_index = disk_ll_init_index;
1211 ll->open_index = disk_ll_open;
1212 ll->max_entries = disk_ll_max_entries;
1213 ll->commit = disk_ll_commit;
1214
1215 ll->nr_blocks = 0;
1216 ll->nr_allocated = 0;
1217
1218 r = ll->init_index(ll);
1219 if (r < 0)
1220 return r;
1221
1222 r = dm_btree_empty(&ll->ref_count_info, &ll->ref_count_root);
1223 if (r < 0)
1224 return r;
1225
1226 return 0;
1227}
1228
1229int sm_ll_open_disk(struct ll_disk *ll, struct dm_transaction_manager *tm,
1230 void *root_le, size_t len)
1231{
1232 int r;
1233 struct disk_sm_root *smr = root_le;
1234
1235 if (len < sizeof(struct disk_sm_root)) {
1236 DMERR("sm_metadata root too small");
1237 return -ENOMEM;
1238 }
1239
1240 r = sm_ll_init(ll, tm);
1241 if (r < 0)
1242 return r;
1243
1244 ll->load_ie = disk_ll_load_ie;
1245 ll->save_ie = disk_ll_save_ie;
1246 ll->init_index = disk_ll_init_index;
1247 ll->open_index = disk_ll_open;
1248 ll->max_entries = disk_ll_max_entries;
1249 ll->commit = disk_ll_commit;
1250
1251 ll->nr_blocks = le64_to_cpu(smr->nr_blocks);
1252 ll->nr_allocated = le64_to_cpu(smr->nr_allocated);
1253 ll->bitmap_root = le64_to_cpu(smr->bitmap_root);
1254 ll->ref_count_root = le64_to_cpu(smr->ref_count_root);
1255
1256 return ll->open_index(ll);
1257}
1258
1259/*----------------------------------------------------------------*/
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2011 Red Hat, Inc.
4 *
5 * This file is released under the GPL.
6 */
7
8#include "dm-space-map-common.h"
9#include "dm-transaction-manager.h"
10#include "dm-btree-internal.h"
11#include "dm-persistent-data-internal.h"
12
13#include <linux/bitops.h>
14#include <linux/device-mapper.h>
15
16#define DM_MSG_PREFIX "space map common"
17
18/*----------------------------------------------------------------*/
19
20/*
21 * Index validator.
22 */
23#define INDEX_CSUM_XOR 160478
24
25static void index_prepare_for_write(struct dm_block_validator *v,
26 struct dm_block *b,
27 size_t block_size)
28{
29 struct disk_metadata_index *mi_le = dm_block_data(b);
30
31 mi_le->blocknr = cpu_to_le64(dm_block_location(b));
32 mi_le->csum = cpu_to_le32(dm_bm_checksum(&mi_le->padding,
33 block_size - sizeof(__le32),
34 INDEX_CSUM_XOR));
35}
36
37static int index_check(struct dm_block_validator *v,
38 struct dm_block *b,
39 size_t block_size)
40{
41 struct disk_metadata_index *mi_le = dm_block_data(b);
42 __le32 csum_disk;
43
44 if (dm_block_location(b) != le64_to_cpu(mi_le->blocknr)) {
45 DMERR_LIMIT("%s failed: blocknr %llu != wanted %llu", __func__,
46 le64_to_cpu(mi_le->blocknr), dm_block_location(b));
47 return -ENOTBLK;
48 }
49
50 csum_disk = cpu_to_le32(dm_bm_checksum(&mi_le->padding,
51 block_size - sizeof(__le32),
52 INDEX_CSUM_XOR));
53 if (csum_disk != mi_le->csum) {
54 DMERR_LIMIT("i%s failed: csum %u != wanted %u", __func__,
55 le32_to_cpu(csum_disk), le32_to_cpu(mi_le->csum));
56 return -EILSEQ;
57 }
58
59 return 0;
60}
61
62static struct dm_block_validator index_validator = {
63 .name = "index",
64 .prepare_for_write = index_prepare_for_write,
65 .check = index_check
66};
67
68/*----------------------------------------------------------------*/
69
70/*
71 * Bitmap validator
72 */
73#define BITMAP_CSUM_XOR 240779
74
75static void dm_bitmap_prepare_for_write(struct dm_block_validator *v,
76 struct dm_block *b,
77 size_t block_size)
78{
79 struct disk_bitmap_header *disk_header = dm_block_data(b);
80
81 disk_header->blocknr = cpu_to_le64(dm_block_location(b));
82 disk_header->csum = cpu_to_le32(dm_bm_checksum(&disk_header->not_used,
83 block_size - sizeof(__le32),
84 BITMAP_CSUM_XOR));
85}
86
87static int dm_bitmap_check(struct dm_block_validator *v,
88 struct dm_block *b,
89 size_t block_size)
90{
91 struct disk_bitmap_header *disk_header = dm_block_data(b);
92 __le32 csum_disk;
93
94 if (dm_block_location(b) != le64_to_cpu(disk_header->blocknr)) {
95 DMERR_LIMIT("bitmap check failed: blocknr %llu != wanted %llu",
96 le64_to_cpu(disk_header->blocknr), dm_block_location(b));
97 return -ENOTBLK;
98 }
99
100 csum_disk = cpu_to_le32(dm_bm_checksum(&disk_header->not_used,
101 block_size - sizeof(__le32),
102 BITMAP_CSUM_XOR));
103 if (csum_disk != disk_header->csum) {
104 DMERR_LIMIT("bitmap check failed: csum %u != wanted %u",
105 le32_to_cpu(csum_disk), le32_to_cpu(disk_header->csum));
106 return -EILSEQ;
107 }
108
109 return 0;
110}
111
112static struct dm_block_validator dm_sm_bitmap_validator = {
113 .name = "sm_bitmap",
114 .prepare_for_write = dm_bitmap_prepare_for_write,
115 .check = dm_bitmap_check,
116};
117
118/*----------------------------------------------------------------*/
119
120#define ENTRIES_PER_WORD 32
121#define ENTRIES_SHIFT 5
122
123static void *dm_bitmap_data(struct dm_block *b)
124{
125 return dm_block_data(b) + sizeof(struct disk_bitmap_header);
126}
127
128#define WORD_MASK_HIGH 0xAAAAAAAAAAAAAAAAULL
129
130static unsigned int dm_bitmap_word_used(void *addr, unsigned int b)
131{
132 __le64 *words_le = addr;
133 __le64 *w_le = words_le + (b >> ENTRIES_SHIFT);
134
135 uint64_t bits = le64_to_cpu(*w_le);
136 uint64_t mask = (bits + WORD_MASK_HIGH + 1) & WORD_MASK_HIGH;
137
138 return !(~bits & mask);
139}
140
141static unsigned int sm_lookup_bitmap(void *addr, unsigned int b)
142{
143 __le64 *words_le = addr;
144 __le64 *w_le = words_le + (b >> ENTRIES_SHIFT);
145 unsigned int hi, lo;
146
147 b = (b & (ENTRIES_PER_WORD - 1)) << 1;
148 hi = !!test_bit_le(b, (void *) w_le);
149 lo = !!test_bit_le(b + 1, (void *) w_le);
150 return (hi << 1) | lo;
151}
152
153static void sm_set_bitmap(void *addr, unsigned int b, unsigned int val)
154{
155 __le64 *words_le = addr;
156 __le64 *w_le = words_le + (b >> ENTRIES_SHIFT);
157
158 b = (b & (ENTRIES_PER_WORD - 1)) << 1;
159
160 if (val & 2)
161 __set_bit_le(b, (void *) w_le);
162 else
163 __clear_bit_le(b, (void *) w_le);
164
165 if (val & 1)
166 __set_bit_le(b + 1, (void *) w_le);
167 else
168 __clear_bit_le(b + 1, (void *) w_le);
169}
170
171static int sm_find_free(void *addr, unsigned int begin, unsigned int end,
172 unsigned int *result)
173{
174 while (begin < end) {
175 if (!(begin & (ENTRIES_PER_WORD - 1)) &&
176 dm_bitmap_word_used(addr, begin)) {
177 begin += ENTRIES_PER_WORD;
178 continue;
179 }
180
181 if (!sm_lookup_bitmap(addr, begin)) {
182 *result = begin;
183 return 0;
184 }
185
186 begin++;
187 }
188
189 return -ENOSPC;
190}
191
192/*----------------------------------------------------------------*/
193
194static int sm_ll_init(struct ll_disk *ll, struct dm_transaction_manager *tm)
195{
196 memset(ll, 0, sizeof(struct ll_disk));
197
198 ll->tm = tm;
199
200 ll->bitmap_info.tm = tm;
201 ll->bitmap_info.levels = 1;
202
203 /*
204 * Because the new bitmap blocks are created via a shadow
205 * operation, the old entry has already had its reference count
206 * decremented and we don't need the btree to do any bookkeeping.
207 */
208 ll->bitmap_info.value_type.size = sizeof(struct disk_index_entry);
209 ll->bitmap_info.value_type.inc = NULL;
210 ll->bitmap_info.value_type.dec = NULL;
211 ll->bitmap_info.value_type.equal = NULL;
212
213 ll->ref_count_info.tm = tm;
214 ll->ref_count_info.levels = 1;
215 ll->ref_count_info.value_type.size = sizeof(uint32_t);
216 ll->ref_count_info.value_type.inc = NULL;
217 ll->ref_count_info.value_type.dec = NULL;
218 ll->ref_count_info.value_type.equal = NULL;
219
220 ll->block_size = dm_bm_block_size(dm_tm_get_bm(tm));
221
222 if (ll->block_size > (1 << 30)) {
223 DMERR("block size too big to hold bitmaps");
224 return -EINVAL;
225 }
226
227 ll->entries_per_block = (ll->block_size - sizeof(struct disk_bitmap_header)) *
228 ENTRIES_PER_BYTE;
229 ll->nr_blocks = 0;
230 ll->bitmap_root = 0;
231 ll->ref_count_root = 0;
232 ll->bitmap_index_changed = false;
233
234 return 0;
235}
236
237int sm_ll_extend(struct ll_disk *ll, dm_block_t extra_blocks)
238{
239 int r;
240 dm_block_t i, nr_blocks, nr_indexes;
241 unsigned int old_blocks, blocks;
242
243 nr_blocks = ll->nr_blocks + extra_blocks;
244 old_blocks = dm_sector_div_up(ll->nr_blocks, ll->entries_per_block);
245 blocks = dm_sector_div_up(nr_blocks, ll->entries_per_block);
246
247 nr_indexes = dm_sector_div_up(nr_blocks, ll->entries_per_block);
248 if (nr_indexes > ll->max_entries(ll)) {
249 DMERR("space map too large");
250 return -EINVAL;
251 }
252
253 /*
254 * We need to set this before the dm_tm_new_block() call below.
255 */
256 ll->nr_blocks = nr_blocks;
257 for (i = old_blocks; i < blocks; i++) {
258 struct dm_block *b;
259 struct disk_index_entry idx;
260
261 r = dm_tm_new_block(ll->tm, &dm_sm_bitmap_validator, &b);
262 if (r < 0)
263 return r;
264
265 idx.blocknr = cpu_to_le64(dm_block_location(b));
266
267 dm_tm_unlock(ll->tm, b);
268
269 idx.nr_free = cpu_to_le32(ll->entries_per_block);
270 idx.none_free_before = 0;
271
272 r = ll->save_ie(ll, i, &idx);
273 if (r < 0)
274 return r;
275 }
276
277 return 0;
278}
279
280int sm_ll_lookup_bitmap(struct ll_disk *ll, dm_block_t b, uint32_t *result)
281{
282 int r;
283 dm_block_t index = b;
284 struct disk_index_entry ie_disk;
285 struct dm_block *blk;
286
287 if (b >= ll->nr_blocks) {
288 DMERR_LIMIT("metadata block out of bounds");
289 return -EINVAL;
290 }
291
292 b = do_div(index, ll->entries_per_block);
293 r = ll->load_ie(ll, index, &ie_disk);
294 if (r < 0)
295 return r;
296
297 r = dm_tm_read_lock(ll->tm, le64_to_cpu(ie_disk.blocknr),
298 &dm_sm_bitmap_validator, &blk);
299 if (r < 0)
300 return r;
301
302 *result = sm_lookup_bitmap(dm_bitmap_data(blk), b);
303
304 dm_tm_unlock(ll->tm, blk);
305
306 return 0;
307}
308
309static int sm_ll_lookup_big_ref_count(struct ll_disk *ll, dm_block_t b,
310 uint32_t *result)
311{
312 __le32 le_rc;
313 int r;
314
315 r = dm_btree_lookup(&ll->ref_count_info, ll->ref_count_root, &b, &le_rc);
316 if (r < 0)
317 return r;
318
319 *result = le32_to_cpu(le_rc);
320
321 return r;
322}
323
324int sm_ll_lookup(struct ll_disk *ll, dm_block_t b, uint32_t *result)
325{
326 int r = sm_ll_lookup_bitmap(ll, b, result);
327
328 if (r)
329 return r;
330
331 if (*result != 3)
332 return r;
333
334 return sm_ll_lookup_big_ref_count(ll, b, result);
335}
336
337int sm_ll_find_free_block(struct ll_disk *ll, dm_block_t begin,
338 dm_block_t end, dm_block_t *result)
339{
340 int r;
341 struct disk_index_entry ie_disk;
342 dm_block_t i, index_begin = begin;
343 dm_block_t index_end = dm_sector_div_up(end, ll->entries_per_block);
344
345 /*
346 * FIXME: Use shifts
347 */
348 begin = do_div(index_begin, ll->entries_per_block);
349 end = do_div(end, ll->entries_per_block);
350 if (end == 0)
351 end = ll->entries_per_block;
352
353 for (i = index_begin; i < index_end; i++, begin = 0) {
354 struct dm_block *blk;
355 unsigned int position;
356 uint32_t bit_end;
357
358 r = ll->load_ie(ll, i, &ie_disk);
359 if (r < 0)
360 return r;
361
362 if (le32_to_cpu(ie_disk.nr_free) == 0)
363 continue;
364
365 r = dm_tm_read_lock(ll->tm, le64_to_cpu(ie_disk.blocknr),
366 &dm_sm_bitmap_validator, &blk);
367 if (r < 0)
368 return r;
369
370 bit_end = (i == index_end - 1) ? end : ll->entries_per_block;
371
372 r = sm_find_free(dm_bitmap_data(blk),
373 max_t(unsigned int, begin, le32_to_cpu(ie_disk.none_free_before)),
374 bit_end, &position);
375 if (r == -ENOSPC) {
376 /*
377 * This might happen because we started searching
378 * part way through the bitmap.
379 */
380 dm_tm_unlock(ll->tm, blk);
381 continue;
382 }
383
384 dm_tm_unlock(ll->tm, blk);
385
386 *result = i * ll->entries_per_block + (dm_block_t) position;
387 return 0;
388 }
389
390 return -ENOSPC;
391}
392
393int sm_ll_find_common_free_block(struct ll_disk *old_ll, struct ll_disk *new_ll,
394 dm_block_t begin, dm_block_t end, dm_block_t *b)
395{
396 int r;
397 uint32_t count;
398
399 do {
400 r = sm_ll_find_free_block(new_ll, begin, new_ll->nr_blocks, b);
401 if (r)
402 break;
403
404 /* double check this block wasn't used in the old transaction */
405 if (*b >= old_ll->nr_blocks)
406 count = 0;
407 else {
408 r = sm_ll_lookup(old_ll, *b, &count);
409 if (r)
410 break;
411
412 if (count)
413 begin = *b + 1;
414 }
415 } while (count);
416
417 return r;
418}
419
420/*----------------------------------------------------------------*/
421
422int sm_ll_insert(struct ll_disk *ll, dm_block_t b,
423 uint32_t ref_count, int32_t *nr_allocations)
424{
425 int r;
426 uint32_t bit, old;
427 struct dm_block *nb;
428 dm_block_t index = b;
429 struct disk_index_entry ie_disk;
430 void *bm_le;
431 int inc;
432
433 bit = do_div(index, ll->entries_per_block);
434 r = ll->load_ie(ll, index, &ie_disk);
435 if (r < 0)
436 return r;
437
438 r = dm_tm_shadow_block(ll->tm, le64_to_cpu(ie_disk.blocknr),
439 &dm_sm_bitmap_validator, &nb, &inc);
440 if (r < 0) {
441 DMERR("dm_tm_shadow_block() failed");
442 return r;
443 }
444 ie_disk.blocknr = cpu_to_le64(dm_block_location(nb));
445 bm_le = dm_bitmap_data(nb);
446
447 old = sm_lookup_bitmap(bm_le, bit);
448 if (old > 2) {
449 r = sm_ll_lookup_big_ref_count(ll, b, &old);
450 if (r < 0) {
451 dm_tm_unlock(ll->tm, nb);
452 return r;
453 }
454 }
455
456 if (r) {
457 dm_tm_unlock(ll->tm, nb);
458 return r;
459 }
460
461 if (ref_count <= 2) {
462 sm_set_bitmap(bm_le, bit, ref_count);
463 dm_tm_unlock(ll->tm, nb);
464
465 if (old > 2) {
466 r = dm_btree_remove(&ll->ref_count_info,
467 ll->ref_count_root,
468 &b, &ll->ref_count_root);
469 if (r)
470 return r;
471 }
472
473 } else {
474 __le32 le_rc = cpu_to_le32(ref_count);
475
476 sm_set_bitmap(bm_le, bit, 3);
477 dm_tm_unlock(ll->tm, nb);
478
479 __dm_bless_for_disk(&le_rc);
480 r = dm_btree_insert(&ll->ref_count_info, ll->ref_count_root,
481 &b, &le_rc, &ll->ref_count_root);
482 if (r < 0) {
483 DMERR("ref count insert failed");
484 return r;
485 }
486 }
487
488 if (ref_count && !old) {
489 *nr_allocations = 1;
490 ll->nr_allocated++;
491 le32_add_cpu(&ie_disk.nr_free, -1);
492 if (le32_to_cpu(ie_disk.none_free_before) == bit)
493 ie_disk.none_free_before = cpu_to_le32(bit + 1);
494
495 } else if (old && !ref_count) {
496 *nr_allocations = -1;
497 ll->nr_allocated--;
498 le32_add_cpu(&ie_disk.nr_free, 1);
499 ie_disk.none_free_before = cpu_to_le32(min(le32_to_cpu(ie_disk.none_free_before), bit));
500 } else
501 *nr_allocations = 0;
502
503 return ll->save_ie(ll, index, &ie_disk);
504}
505
506/*----------------------------------------------------------------*/
507
508/*
509 * Holds useful intermediate results for the range based inc and dec
510 * operations.
511 */
512struct inc_context {
513 struct disk_index_entry ie_disk;
514 struct dm_block *bitmap_block;
515 void *bitmap;
516
517 struct dm_block *overflow_leaf;
518};
519
520static inline void init_inc_context(struct inc_context *ic)
521{
522 ic->bitmap_block = NULL;
523 ic->bitmap = NULL;
524 ic->overflow_leaf = NULL;
525}
526
527static inline void exit_inc_context(struct ll_disk *ll, struct inc_context *ic)
528{
529 if (ic->bitmap_block)
530 dm_tm_unlock(ll->tm, ic->bitmap_block);
531 if (ic->overflow_leaf)
532 dm_tm_unlock(ll->tm, ic->overflow_leaf);
533}
534
535static inline void reset_inc_context(struct ll_disk *ll, struct inc_context *ic)
536{
537 exit_inc_context(ll, ic);
538 init_inc_context(ic);
539}
540
541/*
542 * Confirms a btree node contains a particular key at an index.
543 */
544static bool contains_key(struct btree_node *n, uint64_t key, int index)
545{
546 return index >= 0 &&
547 index < le32_to_cpu(n->header.nr_entries) &&
548 le64_to_cpu(n->keys[index]) == key;
549}
550
551static int __sm_ll_inc_overflow(struct ll_disk *ll, dm_block_t b, struct inc_context *ic)
552{
553 int r;
554 int index;
555 struct btree_node *n;
556 __le32 *v_ptr;
557 uint32_t rc;
558
559 /*
560 * bitmap_block needs to be unlocked because getting the
561 * overflow_leaf may need to allocate, and thus use the space map.
562 */
563 reset_inc_context(ll, ic);
564
565 r = btree_get_overwrite_leaf(&ll->ref_count_info, ll->ref_count_root,
566 b, &index, &ll->ref_count_root, &ic->overflow_leaf);
567 if (r < 0)
568 return r;
569
570 n = dm_block_data(ic->overflow_leaf);
571
572 if (!contains_key(n, b, index)) {
573 DMERR("overflow btree is missing an entry");
574 return -EINVAL;
575 }
576
577 v_ptr = value_ptr(n, index);
578 rc = le32_to_cpu(*v_ptr) + 1;
579 *v_ptr = cpu_to_le32(rc);
580
581 return 0;
582}
583
584static int sm_ll_inc_overflow(struct ll_disk *ll, dm_block_t b, struct inc_context *ic)
585{
586 int index;
587 struct btree_node *n;
588 __le32 *v_ptr;
589 uint32_t rc;
590
591 /*
592 * Do we already have the correct overflow leaf?
593 */
594 if (ic->overflow_leaf) {
595 n = dm_block_data(ic->overflow_leaf);
596 index = lower_bound(n, b);
597 if (contains_key(n, b, index)) {
598 v_ptr = value_ptr(n, index);
599 rc = le32_to_cpu(*v_ptr) + 1;
600 *v_ptr = cpu_to_le32(rc);
601
602 return 0;
603 }
604 }
605
606 return __sm_ll_inc_overflow(ll, b, ic);
607}
608
609static inline int shadow_bitmap(struct ll_disk *ll, struct inc_context *ic)
610{
611 int r, inc;
612
613 r = dm_tm_shadow_block(ll->tm, le64_to_cpu(ic->ie_disk.blocknr),
614 &dm_sm_bitmap_validator, &ic->bitmap_block, &inc);
615 if (r < 0) {
616 DMERR("dm_tm_shadow_block() failed");
617 return r;
618 }
619 ic->ie_disk.blocknr = cpu_to_le64(dm_block_location(ic->bitmap_block));
620 ic->bitmap = dm_bitmap_data(ic->bitmap_block);
621 return 0;
622}
623
624/*
625 * Once shadow_bitmap has been called, which always happens at the start of inc/dec,
626 * we can reopen the bitmap with a simple write lock, rather than re calling
627 * dm_tm_shadow_block().
628 */
629static inline int ensure_bitmap(struct ll_disk *ll, struct inc_context *ic)
630{
631 if (!ic->bitmap_block) {
632 int r = dm_bm_write_lock(dm_tm_get_bm(ll->tm), le64_to_cpu(ic->ie_disk.blocknr),
633 &dm_sm_bitmap_validator, &ic->bitmap_block);
634 if (r) {
635 DMERR("unable to re-get write lock for bitmap");
636 return r;
637 }
638 ic->bitmap = dm_bitmap_data(ic->bitmap_block);
639 }
640
641 return 0;
642}
643
644/*
645 * Loops round incrementing entries in a single bitmap.
646 */
647static inline int sm_ll_inc_bitmap(struct ll_disk *ll, dm_block_t b,
648 uint32_t bit, uint32_t bit_end,
649 int32_t *nr_allocations, dm_block_t *new_b,
650 struct inc_context *ic)
651{
652 int r;
653 __le32 le_rc;
654 uint32_t old;
655
656 for (; bit != bit_end; bit++, b++) {
657 /*
658 * We only need to drop the bitmap if we need to find a new btree
659 * leaf for the overflow. So if it was dropped last iteration,
660 * we now re-get it.
661 */
662 r = ensure_bitmap(ll, ic);
663 if (r)
664 return r;
665
666 old = sm_lookup_bitmap(ic->bitmap, bit);
667 switch (old) {
668 case 0:
669 /* inc bitmap, adjust nr_allocated */
670 sm_set_bitmap(ic->bitmap, bit, 1);
671 (*nr_allocations)++;
672 ll->nr_allocated++;
673 le32_add_cpu(&ic->ie_disk.nr_free, -1);
674 if (le32_to_cpu(ic->ie_disk.none_free_before) == bit)
675 ic->ie_disk.none_free_before = cpu_to_le32(bit + 1);
676 break;
677
678 case 1:
679 /* inc bitmap */
680 sm_set_bitmap(ic->bitmap, bit, 2);
681 break;
682
683 case 2:
684 /* inc bitmap and insert into overflow */
685 sm_set_bitmap(ic->bitmap, bit, 3);
686 reset_inc_context(ll, ic);
687
688 le_rc = cpu_to_le32(3);
689 __dm_bless_for_disk(&le_rc);
690 r = dm_btree_insert(&ll->ref_count_info, ll->ref_count_root,
691 &b, &le_rc, &ll->ref_count_root);
692 if (r < 0) {
693 DMERR("ref count insert failed");
694 return r;
695 }
696 break;
697
698 default:
699 /*
700 * inc within the overflow tree only.
701 */
702 r = sm_ll_inc_overflow(ll, b, ic);
703 if (r < 0)
704 return r;
705 }
706 }
707
708 *new_b = b;
709 return 0;
710}
711
712/*
713 * Finds a bitmap that contains entries in the block range, and increments
714 * them.
715 */
716static int __sm_ll_inc(struct ll_disk *ll, dm_block_t b, dm_block_t e,
717 int32_t *nr_allocations, dm_block_t *new_b)
718{
719 int r;
720 struct inc_context ic;
721 uint32_t bit, bit_end;
722 dm_block_t index = b;
723
724 init_inc_context(&ic);
725
726 bit = do_div(index, ll->entries_per_block);
727 r = ll->load_ie(ll, index, &ic.ie_disk);
728 if (r < 0)
729 return r;
730
731 r = shadow_bitmap(ll, &ic);
732 if (r)
733 return r;
734
735 bit_end = min(bit + (e - b), (dm_block_t) ll->entries_per_block);
736 r = sm_ll_inc_bitmap(ll, b, bit, bit_end, nr_allocations, new_b, &ic);
737
738 exit_inc_context(ll, &ic);
739
740 if (r)
741 return r;
742
743 return ll->save_ie(ll, index, &ic.ie_disk);
744}
745
746int sm_ll_inc(struct ll_disk *ll, dm_block_t b, dm_block_t e,
747 int32_t *nr_allocations)
748{
749 *nr_allocations = 0;
750 while (b != e) {
751 int r = __sm_ll_inc(ll, b, e, nr_allocations, &b);
752
753 if (r)
754 return r;
755 }
756
757 return 0;
758}
759
760/*----------------------------------------------------------------*/
761
762static int __sm_ll_del_overflow(struct ll_disk *ll, dm_block_t b,
763 struct inc_context *ic)
764{
765 reset_inc_context(ll, ic);
766 return dm_btree_remove(&ll->ref_count_info, ll->ref_count_root,
767 &b, &ll->ref_count_root);
768}
769
770static int __sm_ll_dec_overflow(struct ll_disk *ll, dm_block_t b,
771 struct inc_context *ic, uint32_t *old_rc)
772{
773 int r;
774 int index = -1;
775 struct btree_node *n;
776 __le32 *v_ptr;
777 uint32_t rc;
778
779 reset_inc_context(ll, ic);
780 r = btree_get_overwrite_leaf(&ll->ref_count_info, ll->ref_count_root,
781 b, &index, &ll->ref_count_root, &ic->overflow_leaf);
782 if (r < 0)
783 return r;
784
785 n = dm_block_data(ic->overflow_leaf);
786
787 if (!contains_key(n, b, index)) {
788 DMERR("overflow btree is missing an entry");
789 return -EINVAL;
790 }
791
792 v_ptr = value_ptr(n, index);
793 rc = le32_to_cpu(*v_ptr);
794 *old_rc = rc;
795
796 if (rc == 3)
797 return __sm_ll_del_overflow(ll, b, ic);
798
799 rc--;
800 *v_ptr = cpu_to_le32(rc);
801 return 0;
802}
803
804static int sm_ll_dec_overflow(struct ll_disk *ll, dm_block_t b,
805 struct inc_context *ic, uint32_t *old_rc)
806{
807 /*
808 * Do we already have the correct overflow leaf?
809 */
810 if (ic->overflow_leaf) {
811 int index;
812 struct btree_node *n;
813 __le32 *v_ptr;
814 uint32_t rc;
815
816 n = dm_block_data(ic->overflow_leaf);
817 index = lower_bound(n, b);
818 if (contains_key(n, b, index)) {
819 v_ptr = value_ptr(n, index);
820 rc = le32_to_cpu(*v_ptr);
821 *old_rc = rc;
822
823 if (rc > 3) {
824 rc--;
825 *v_ptr = cpu_to_le32(rc);
826 return 0;
827 } else {
828 return __sm_ll_del_overflow(ll, b, ic);
829 }
830
831 }
832 }
833
834 return __sm_ll_dec_overflow(ll, b, ic, old_rc);
835}
836
837/*
838 * Loops round incrementing entries in a single bitmap.
839 */
840static inline int sm_ll_dec_bitmap(struct ll_disk *ll, dm_block_t b,
841 uint32_t bit, uint32_t bit_end,
842 struct inc_context *ic,
843 int32_t *nr_allocations, dm_block_t *new_b)
844{
845 int r;
846 uint32_t old;
847
848 for (; bit != bit_end; bit++, b++) {
849 /*
850 * We only need to drop the bitmap if we need to find a new btree
851 * leaf for the overflow. So if it was dropped last iteration,
852 * we now re-get it.
853 */
854 r = ensure_bitmap(ll, ic);
855 if (r)
856 return r;
857
858 old = sm_lookup_bitmap(ic->bitmap, bit);
859 switch (old) {
860 case 0:
861 DMERR("unable to decrement block");
862 return -EINVAL;
863
864 case 1:
865 /* dec bitmap */
866 sm_set_bitmap(ic->bitmap, bit, 0);
867 (*nr_allocations)--;
868 ll->nr_allocated--;
869 le32_add_cpu(&ic->ie_disk.nr_free, 1);
870 ic->ie_disk.none_free_before =
871 cpu_to_le32(min(le32_to_cpu(ic->ie_disk.none_free_before), bit));
872 break;
873
874 case 2:
875 /* dec bitmap and insert into overflow */
876 sm_set_bitmap(ic->bitmap, bit, 1);
877 break;
878
879 case 3:
880 r = sm_ll_dec_overflow(ll, b, ic, &old);
881 if (r < 0)
882 return r;
883
884 if (old == 3) {
885 r = ensure_bitmap(ll, ic);
886 if (r)
887 return r;
888
889 sm_set_bitmap(ic->bitmap, bit, 2);
890 }
891 break;
892 }
893 }
894
895 *new_b = b;
896 return 0;
897}
898
899static int __sm_ll_dec(struct ll_disk *ll, dm_block_t b, dm_block_t e,
900 int32_t *nr_allocations, dm_block_t *new_b)
901{
902 int r;
903 uint32_t bit, bit_end;
904 struct inc_context ic;
905 dm_block_t index = b;
906
907 init_inc_context(&ic);
908
909 bit = do_div(index, ll->entries_per_block);
910 r = ll->load_ie(ll, index, &ic.ie_disk);
911 if (r < 0)
912 return r;
913
914 r = shadow_bitmap(ll, &ic);
915 if (r)
916 return r;
917
918 bit_end = min(bit + (e - b), (dm_block_t) ll->entries_per_block);
919 r = sm_ll_dec_bitmap(ll, b, bit, bit_end, &ic, nr_allocations, new_b);
920 exit_inc_context(ll, &ic);
921
922 if (r)
923 return r;
924
925 return ll->save_ie(ll, index, &ic.ie_disk);
926}
927
928int sm_ll_dec(struct ll_disk *ll, dm_block_t b, dm_block_t e,
929 int32_t *nr_allocations)
930{
931 *nr_allocations = 0;
932 while (b != e) {
933 int r = __sm_ll_dec(ll, b, e, nr_allocations, &b);
934
935 if (r)
936 return r;
937 }
938
939 return 0;
940}
941
942/*----------------------------------------------------------------*/
943
944int sm_ll_commit(struct ll_disk *ll)
945{
946 int r = 0;
947
948 if (ll->bitmap_index_changed) {
949 r = ll->commit(ll);
950 if (!r)
951 ll->bitmap_index_changed = false;
952 }
953
954 return r;
955}
956
957/*----------------------------------------------------------------*/
958
959static int metadata_ll_load_ie(struct ll_disk *ll, dm_block_t index,
960 struct disk_index_entry *ie)
961{
962 memcpy(ie, ll->mi_le.index + index, sizeof(*ie));
963 return 0;
964}
965
966static int metadata_ll_save_ie(struct ll_disk *ll, dm_block_t index,
967 struct disk_index_entry *ie)
968{
969 ll->bitmap_index_changed = true;
970 memcpy(ll->mi_le.index + index, ie, sizeof(*ie));
971 return 0;
972}
973
974static int metadata_ll_init_index(struct ll_disk *ll)
975{
976 int r;
977 struct dm_block *b;
978
979 r = dm_tm_new_block(ll->tm, &index_validator, &b);
980 if (r < 0)
981 return r;
982
983 ll->bitmap_root = dm_block_location(b);
984
985 dm_tm_unlock(ll->tm, b);
986
987 return 0;
988}
989
990static int metadata_ll_open(struct ll_disk *ll)
991{
992 int r;
993 struct dm_block *block;
994
995 r = dm_tm_read_lock(ll->tm, ll->bitmap_root,
996 &index_validator, &block);
997 if (r)
998 return r;
999
1000 memcpy(&ll->mi_le, dm_block_data(block), sizeof(ll->mi_le));
1001 dm_tm_unlock(ll->tm, block);
1002
1003 return 0;
1004}
1005
1006static dm_block_t metadata_ll_max_entries(struct ll_disk *ll)
1007{
1008 return MAX_METADATA_BITMAPS;
1009}
1010
1011static int metadata_ll_commit(struct ll_disk *ll)
1012{
1013 int r, inc;
1014 struct dm_block *b;
1015
1016 r = dm_tm_shadow_block(ll->tm, ll->bitmap_root, &index_validator, &b, &inc);
1017 if (r)
1018 return r;
1019
1020 memcpy(dm_block_data(b), &ll->mi_le, sizeof(ll->mi_le));
1021 ll->bitmap_root = dm_block_location(b);
1022
1023 dm_tm_unlock(ll->tm, b);
1024
1025 return 0;
1026}
1027
1028int sm_ll_new_metadata(struct ll_disk *ll, struct dm_transaction_manager *tm)
1029{
1030 int r;
1031
1032 r = sm_ll_init(ll, tm);
1033 if (r < 0)
1034 return r;
1035
1036 ll->load_ie = metadata_ll_load_ie;
1037 ll->save_ie = metadata_ll_save_ie;
1038 ll->init_index = metadata_ll_init_index;
1039 ll->open_index = metadata_ll_open;
1040 ll->max_entries = metadata_ll_max_entries;
1041 ll->commit = metadata_ll_commit;
1042
1043 ll->nr_blocks = 0;
1044 ll->nr_allocated = 0;
1045
1046 r = ll->init_index(ll);
1047 if (r < 0)
1048 return r;
1049
1050 r = dm_btree_empty(&ll->ref_count_info, &ll->ref_count_root);
1051 if (r < 0)
1052 return r;
1053
1054 return 0;
1055}
1056
1057int sm_ll_open_metadata(struct ll_disk *ll, struct dm_transaction_manager *tm,
1058 void *root_le, size_t len)
1059{
1060 int r;
1061 struct disk_sm_root smr;
1062
1063 if (len < sizeof(struct disk_sm_root)) {
1064 DMERR("sm_metadata root too small");
1065 return -ENOMEM;
1066 }
1067
1068 /*
1069 * We don't know the alignment of the root_le buffer, so need to
1070 * copy into a new structure.
1071 */
1072 memcpy(&smr, root_le, sizeof(smr));
1073
1074 r = sm_ll_init(ll, tm);
1075 if (r < 0)
1076 return r;
1077
1078 ll->load_ie = metadata_ll_load_ie;
1079 ll->save_ie = metadata_ll_save_ie;
1080 ll->init_index = metadata_ll_init_index;
1081 ll->open_index = metadata_ll_open;
1082 ll->max_entries = metadata_ll_max_entries;
1083 ll->commit = metadata_ll_commit;
1084
1085 ll->nr_blocks = le64_to_cpu(smr.nr_blocks);
1086 ll->nr_allocated = le64_to_cpu(smr.nr_allocated);
1087 ll->bitmap_root = le64_to_cpu(smr.bitmap_root);
1088 ll->ref_count_root = le64_to_cpu(smr.ref_count_root);
1089
1090 return ll->open_index(ll);
1091}
1092
1093/*----------------------------------------------------------------*/
1094
1095static inline int ie_cache_writeback(struct ll_disk *ll, struct ie_cache *iec)
1096{
1097 iec->dirty = false;
1098 __dm_bless_for_disk(iec->ie);
1099 return dm_btree_insert(&ll->bitmap_info, ll->bitmap_root,
1100 &iec->index, &iec->ie, &ll->bitmap_root);
1101}
1102
1103static inline unsigned int hash_index(dm_block_t index)
1104{
1105 return dm_hash_block(index, IE_CACHE_MASK);
1106}
1107
1108static int disk_ll_load_ie(struct ll_disk *ll, dm_block_t index,
1109 struct disk_index_entry *ie)
1110{
1111 int r;
1112 unsigned int h = hash_index(index);
1113 struct ie_cache *iec = ll->ie_cache + h;
1114
1115 if (iec->valid) {
1116 if (iec->index == index) {
1117 memcpy(ie, &iec->ie, sizeof(*ie));
1118 return 0;
1119 }
1120
1121 if (iec->dirty) {
1122 r = ie_cache_writeback(ll, iec);
1123 if (r)
1124 return r;
1125 }
1126 }
1127
1128 r = dm_btree_lookup(&ll->bitmap_info, ll->bitmap_root, &index, ie);
1129 if (!r) {
1130 iec->valid = true;
1131 iec->dirty = false;
1132 iec->index = index;
1133 memcpy(&iec->ie, ie, sizeof(*ie));
1134 }
1135
1136 return r;
1137}
1138
1139static int disk_ll_save_ie(struct ll_disk *ll, dm_block_t index,
1140 struct disk_index_entry *ie)
1141{
1142 int r;
1143 unsigned int h = hash_index(index);
1144 struct ie_cache *iec = ll->ie_cache + h;
1145
1146 ll->bitmap_index_changed = true;
1147 if (iec->valid) {
1148 if (iec->index == index) {
1149 memcpy(&iec->ie, ie, sizeof(*ie));
1150 iec->dirty = true;
1151 return 0;
1152 }
1153
1154 if (iec->dirty) {
1155 r = ie_cache_writeback(ll, iec);
1156 if (r)
1157 return r;
1158 }
1159 }
1160
1161 iec->valid = true;
1162 iec->dirty = true;
1163 iec->index = index;
1164 memcpy(&iec->ie, ie, sizeof(*ie));
1165 return 0;
1166}
1167
1168static int disk_ll_init_index(struct ll_disk *ll)
1169{
1170 unsigned int i;
1171
1172 for (i = 0; i < IE_CACHE_SIZE; i++) {
1173 struct ie_cache *iec = ll->ie_cache + i;
1174
1175 iec->valid = false;
1176 iec->dirty = false;
1177 }
1178 return dm_btree_empty(&ll->bitmap_info, &ll->bitmap_root);
1179}
1180
1181static int disk_ll_open(struct ll_disk *ll)
1182{
1183 return 0;
1184}
1185
1186static dm_block_t disk_ll_max_entries(struct ll_disk *ll)
1187{
1188 return -1ULL;
1189}
1190
1191static int disk_ll_commit(struct ll_disk *ll)
1192{
1193 int r = 0;
1194 unsigned int i;
1195
1196 for (i = 0; i < IE_CACHE_SIZE; i++) {
1197 struct ie_cache *iec = ll->ie_cache + i;
1198
1199 if (iec->valid && iec->dirty)
1200 r = ie_cache_writeback(ll, iec);
1201 }
1202
1203 return r;
1204}
1205
1206int sm_ll_new_disk(struct ll_disk *ll, struct dm_transaction_manager *tm)
1207{
1208 int r;
1209
1210 r = sm_ll_init(ll, tm);
1211 if (r < 0)
1212 return r;
1213
1214 ll->load_ie = disk_ll_load_ie;
1215 ll->save_ie = disk_ll_save_ie;
1216 ll->init_index = disk_ll_init_index;
1217 ll->open_index = disk_ll_open;
1218 ll->max_entries = disk_ll_max_entries;
1219 ll->commit = disk_ll_commit;
1220
1221 ll->nr_blocks = 0;
1222 ll->nr_allocated = 0;
1223
1224 r = ll->init_index(ll);
1225 if (r < 0)
1226 return r;
1227
1228 r = dm_btree_empty(&ll->ref_count_info, &ll->ref_count_root);
1229 if (r < 0)
1230 return r;
1231
1232 return 0;
1233}
1234
1235int sm_ll_open_disk(struct ll_disk *ll, struct dm_transaction_manager *tm,
1236 void *root_le, size_t len)
1237{
1238 int r;
1239 struct disk_sm_root *smr = root_le;
1240
1241 if (len < sizeof(struct disk_sm_root)) {
1242 DMERR("sm_metadata root too small");
1243 return -ENOMEM;
1244 }
1245
1246 r = sm_ll_init(ll, tm);
1247 if (r < 0)
1248 return r;
1249
1250 ll->load_ie = disk_ll_load_ie;
1251 ll->save_ie = disk_ll_save_ie;
1252 ll->init_index = disk_ll_init_index;
1253 ll->open_index = disk_ll_open;
1254 ll->max_entries = disk_ll_max_entries;
1255 ll->commit = disk_ll_commit;
1256
1257 ll->nr_blocks = le64_to_cpu(smr->nr_blocks);
1258 ll->nr_allocated = le64_to_cpu(smr->nr_allocated);
1259 ll->bitmap_root = le64_to_cpu(smr->bitmap_root);
1260 ll->ref_count_root = le64_to_cpu(smr->ref_count_root);
1261
1262 return ll->open_index(ll);
1263}
1264
1265/*----------------------------------------------------------------*/