Linux 4.19.133
[linux/fpc-iii.git] / drivers / md / persistent-data / dm-space-map-common.c
blob17aef55ed708a2addd1adfc9d6ab0ddaf2c83927
1 /*
2 * Copyright (C) 2011 Red Hat, Inc.
4 * This file is released under the GPL.
5 */
7 #include "dm-space-map-common.h"
8 #include "dm-transaction-manager.h"
10 #include <linux/bitops.h>
11 #include <linux/device-mapper.h>
13 #define DM_MSG_PREFIX "space map common"
15 /*----------------------------------------------------------------*/
18 * Index validator.
20 #define INDEX_CSUM_XOR 160478
22 static void index_prepare_for_write(struct dm_block_validator *v,
23 struct dm_block *b,
24 size_t block_size)
26 struct disk_metadata_index *mi_le = dm_block_data(b);
28 mi_le->blocknr = cpu_to_le64(dm_block_location(b));
29 mi_le->csum = cpu_to_le32(dm_bm_checksum(&mi_le->padding,
30 block_size - sizeof(__le32),
31 INDEX_CSUM_XOR));
34 static int index_check(struct dm_block_validator *v,
35 struct dm_block *b,
36 size_t block_size)
38 struct disk_metadata_index *mi_le = dm_block_data(b);
39 __le32 csum_disk;
41 if (dm_block_location(b) != le64_to_cpu(mi_le->blocknr)) {
42 DMERR_LIMIT("index_check failed: blocknr %llu != wanted %llu",
43 le64_to_cpu(mi_le->blocknr), dm_block_location(b));
44 return -ENOTBLK;
47 csum_disk = cpu_to_le32(dm_bm_checksum(&mi_le->padding,
48 block_size - sizeof(__le32),
49 INDEX_CSUM_XOR));
50 if (csum_disk != mi_le->csum) {
51 DMERR_LIMIT("index_check failed: csum %u != wanted %u",
52 le32_to_cpu(csum_disk), le32_to_cpu(mi_le->csum));
53 return -EILSEQ;
56 return 0;
59 static struct dm_block_validator index_validator = {
60 .name = "index",
61 .prepare_for_write = index_prepare_for_write,
62 .check = index_check
65 /*----------------------------------------------------------------*/
68 * Bitmap validator
70 #define BITMAP_CSUM_XOR 240779
72 static void dm_bitmap_prepare_for_write(struct dm_block_validator *v,
73 struct dm_block *b,
74 size_t block_size)
76 struct disk_bitmap_header *disk_header = dm_block_data(b);
78 disk_header->blocknr = cpu_to_le64(dm_block_location(b));
79 disk_header->csum = cpu_to_le32(dm_bm_checksum(&disk_header->not_used,
80 block_size - sizeof(__le32),
81 BITMAP_CSUM_XOR));
84 static int dm_bitmap_check(struct dm_block_validator *v,
85 struct dm_block *b,
86 size_t block_size)
88 struct disk_bitmap_header *disk_header = dm_block_data(b);
89 __le32 csum_disk;
91 if (dm_block_location(b) != le64_to_cpu(disk_header->blocknr)) {
92 DMERR_LIMIT("bitmap check failed: blocknr %llu != wanted %llu",
93 le64_to_cpu(disk_header->blocknr), dm_block_location(b));
94 return -ENOTBLK;
97 csum_disk = cpu_to_le32(dm_bm_checksum(&disk_header->not_used,
98 block_size - sizeof(__le32),
99 BITMAP_CSUM_XOR));
100 if (csum_disk != disk_header->csum) {
101 DMERR_LIMIT("bitmap check failed: csum %u != wanted %u",
102 le32_to_cpu(csum_disk), le32_to_cpu(disk_header->csum));
103 return -EILSEQ;
106 return 0;
109 static struct dm_block_validator dm_sm_bitmap_validator = {
110 .name = "sm_bitmap",
111 .prepare_for_write = dm_bitmap_prepare_for_write,
112 .check = dm_bitmap_check,
115 /*----------------------------------------------------------------*/
117 #define ENTRIES_PER_WORD 32
118 #define ENTRIES_SHIFT 5
120 static void *dm_bitmap_data(struct dm_block *b)
122 return dm_block_data(b) + sizeof(struct disk_bitmap_header);
125 #define WORD_MASK_HIGH 0xAAAAAAAAAAAAAAAAULL
127 static unsigned dm_bitmap_word_used(void *addr, unsigned b)
129 __le64 *words_le = addr;
130 __le64 *w_le = words_le + (b >> ENTRIES_SHIFT);
132 uint64_t bits = le64_to_cpu(*w_le);
133 uint64_t mask = (bits + WORD_MASK_HIGH + 1) & WORD_MASK_HIGH;
135 return !(~bits & mask);
138 static unsigned sm_lookup_bitmap(void *addr, unsigned b)
140 __le64 *words_le = addr;
141 __le64 *w_le = words_le + (b >> ENTRIES_SHIFT);
142 unsigned hi, lo;
144 b = (b & (ENTRIES_PER_WORD - 1)) << 1;
145 hi = !!test_bit_le(b, (void *) w_le);
146 lo = !!test_bit_le(b + 1, (void *) w_le);
147 return (hi << 1) | lo;
150 static void sm_set_bitmap(void *addr, unsigned b, unsigned val)
152 __le64 *words_le = addr;
153 __le64 *w_le = words_le + (b >> ENTRIES_SHIFT);
155 b = (b & (ENTRIES_PER_WORD - 1)) << 1;
157 if (val & 2)
158 __set_bit_le(b, (void *) w_le);
159 else
160 __clear_bit_le(b, (void *) w_le);
162 if (val & 1)
163 __set_bit_le(b + 1, (void *) w_le);
164 else
165 __clear_bit_le(b + 1, (void *) w_le);
168 static int sm_find_free(void *addr, unsigned begin, unsigned end,
169 unsigned *result)
171 while (begin < end) {
172 if (!(begin & (ENTRIES_PER_WORD - 1)) &&
173 dm_bitmap_word_used(addr, begin)) {
174 begin += ENTRIES_PER_WORD;
175 continue;
178 if (!sm_lookup_bitmap(addr, begin)) {
179 *result = begin;
180 return 0;
183 begin++;
186 return -ENOSPC;
189 /*----------------------------------------------------------------*/
191 static int sm_ll_init(struct ll_disk *ll, struct dm_transaction_manager *tm)
193 ll->tm = tm;
195 ll->bitmap_info.tm = tm;
196 ll->bitmap_info.levels = 1;
199 * Because the new bitmap blocks are created via a shadow
200 * operation, the old entry has already had its reference count
201 * decremented and we don't need the btree to do any bookkeeping.
203 ll->bitmap_info.value_type.size = sizeof(struct disk_index_entry);
204 ll->bitmap_info.value_type.inc = NULL;
205 ll->bitmap_info.value_type.dec = NULL;
206 ll->bitmap_info.value_type.equal = NULL;
208 ll->ref_count_info.tm = tm;
209 ll->ref_count_info.levels = 1;
210 ll->ref_count_info.value_type.size = sizeof(uint32_t);
211 ll->ref_count_info.value_type.inc = NULL;
212 ll->ref_count_info.value_type.dec = NULL;
213 ll->ref_count_info.value_type.equal = NULL;
215 ll->block_size = dm_bm_block_size(dm_tm_get_bm(tm));
217 if (ll->block_size > (1 << 30)) {
218 DMERR("block size too big to hold bitmaps");
219 return -EINVAL;
222 ll->entries_per_block = (ll->block_size - sizeof(struct disk_bitmap_header)) *
223 ENTRIES_PER_BYTE;
224 ll->nr_blocks = 0;
225 ll->bitmap_root = 0;
226 ll->ref_count_root = 0;
227 ll->bitmap_index_changed = false;
229 return 0;
232 int sm_ll_extend(struct ll_disk *ll, dm_block_t extra_blocks)
234 int r;
235 dm_block_t i, nr_blocks, nr_indexes;
236 unsigned old_blocks, blocks;
238 nr_blocks = ll->nr_blocks + extra_blocks;
239 old_blocks = dm_sector_div_up(ll->nr_blocks, ll->entries_per_block);
240 blocks = dm_sector_div_up(nr_blocks, ll->entries_per_block);
242 nr_indexes = dm_sector_div_up(nr_blocks, ll->entries_per_block);
243 if (nr_indexes > ll->max_entries(ll)) {
244 DMERR("space map too large");
245 return -EINVAL;
249 * We need to set this before the dm_tm_new_block() call below.
251 ll->nr_blocks = nr_blocks;
252 for (i = old_blocks; i < blocks; i++) {
253 struct dm_block *b;
254 struct disk_index_entry idx;
256 r = dm_tm_new_block(ll->tm, &dm_sm_bitmap_validator, &b);
257 if (r < 0)
258 return r;
260 idx.blocknr = cpu_to_le64(dm_block_location(b));
262 dm_tm_unlock(ll->tm, b);
264 idx.nr_free = cpu_to_le32(ll->entries_per_block);
265 idx.none_free_before = 0;
267 r = ll->save_ie(ll, i, &idx);
268 if (r < 0)
269 return r;
272 return 0;
275 int sm_ll_lookup_bitmap(struct ll_disk *ll, dm_block_t b, uint32_t *result)
277 int r;
278 dm_block_t index = b;
279 struct disk_index_entry ie_disk;
280 struct dm_block *blk;
282 b = do_div(index, ll->entries_per_block);
283 r = ll->load_ie(ll, index, &ie_disk);
284 if (r < 0)
285 return r;
287 r = dm_tm_read_lock(ll->tm, le64_to_cpu(ie_disk.blocknr),
288 &dm_sm_bitmap_validator, &blk);
289 if (r < 0)
290 return r;
292 *result = sm_lookup_bitmap(dm_bitmap_data(blk), b);
294 dm_tm_unlock(ll->tm, blk);
296 return 0;
299 static int sm_ll_lookup_big_ref_count(struct ll_disk *ll, dm_block_t b,
300 uint32_t *result)
302 __le32 le_rc;
303 int r;
305 r = dm_btree_lookup(&ll->ref_count_info, ll->ref_count_root, &b, &le_rc);
306 if (r < 0)
307 return r;
309 *result = le32_to_cpu(le_rc);
311 return r;
314 int sm_ll_lookup(struct ll_disk *ll, dm_block_t b, uint32_t *result)
316 int r = sm_ll_lookup_bitmap(ll, b, result);
318 if (r)
319 return r;
321 if (*result != 3)
322 return r;
324 return sm_ll_lookup_big_ref_count(ll, b, result);
327 int sm_ll_find_free_block(struct ll_disk *ll, dm_block_t begin,
328 dm_block_t end, dm_block_t *result)
330 int r;
331 struct disk_index_entry ie_disk;
332 dm_block_t i, index_begin = begin;
333 dm_block_t index_end = dm_sector_div_up(end, ll->entries_per_block);
336 * FIXME: Use shifts
338 begin = do_div(index_begin, ll->entries_per_block);
339 end = do_div(end, ll->entries_per_block);
341 for (i = index_begin; i < index_end; i++, begin = 0) {
342 struct dm_block *blk;
343 unsigned position;
344 uint32_t bit_end;
346 r = ll->load_ie(ll, i, &ie_disk);
347 if (r < 0)
348 return r;
350 if (le32_to_cpu(ie_disk.nr_free) == 0)
351 continue;
353 r = dm_tm_read_lock(ll->tm, le64_to_cpu(ie_disk.blocknr),
354 &dm_sm_bitmap_validator, &blk);
355 if (r < 0)
356 return r;
358 bit_end = (i == index_end - 1) ? end : ll->entries_per_block;
360 r = sm_find_free(dm_bitmap_data(blk),
361 max_t(unsigned, begin, le32_to_cpu(ie_disk.none_free_before)),
362 bit_end, &position);
363 if (r == -ENOSPC) {
365 * This might happen because we started searching
366 * part way through the bitmap.
368 dm_tm_unlock(ll->tm, blk);
369 continue;
371 } else if (r < 0) {
372 dm_tm_unlock(ll->tm, blk);
373 return r;
376 dm_tm_unlock(ll->tm, blk);
378 *result = i * ll->entries_per_block + (dm_block_t) position;
379 return 0;
382 return -ENOSPC;
385 int sm_ll_find_common_free_block(struct ll_disk *old_ll, struct ll_disk *new_ll,
386 dm_block_t begin, dm_block_t end, dm_block_t *b)
388 int r;
389 uint32_t count;
391 do {
392 r = sm_ll_find_free_block(new_ll, begin, new_ll->nr_blocks, b);
393 if (r)
394 break;
396 /* double check this block wasn't used in the old transaction */
397 if (*b >= old_ll->nr_blocks)
398 count = 0;
399 else {
400 r = sm_ll_lookup(old_ll, *b, &count);
401 if (r)
402 break;
404 if (count)
405 begin = *b + 1;
407 } while (count);
409 return r;
412 static int sm_ll_mutate(struct ll_disk *ll, dm_block_t b,
413 int (*mutator)(void *context, uint32_t old, uint32_t *new),
414 void *context, enum allocation_event *ev)
416 int r;
417 uint32_t bit, old, ref_count;
418 struct dm_block *nb;
419 dm_block_t index = b;
420 struct disk_index_entry ie_disk;
421 void *bm_le;
422 int inc;
424 bit = do_div(index, ll->entries_per_block);
425 r = ll->load_ie(ll, index, &ie_disk);
426 if (r < 0)
427 return r;
429 r = dm_tm_shadow_block(ll->tm, le64_to_cpu(ie_disk.blocknr),
430 &dm_sm_bitmap_validator, &nb, &inc);
431 if (r < 0) {
432 DMERR("dm_tm_shadow_block() failed");
433 return r;
435 ie_disk.blocknr = cpu_to_le64(dm_block_location(nb));
437 bm_le = dm_bitmap_data(nb);
438 old = sm_lookup_bitmap(bm_le, bit);
440 if (old > 2) {
441 r = sm_ll_lookup_big_ref_count(ll, b, &old);
442 if (r < 0) {
443 dm_tm_unlock(ll->tm, nb);
444 return r;
448 r = mutator(context, old, &ref_count);
449 if (r) {
450 dm_tm_unlock(ll->tm, nb);
451 return r;
454 if (ref_count <= 2) {
455 sm_set_bitmap(bm_le, bit, ref_count);
457 dm_tm_unlock(ll->tm, nb);
459 if (old > 2) {
460 r = dm_btree_remove(&ll->ref_count_info,
461 ll->ref_count_root,
462 &b, &ll->ref_count_root);
463 if (r)
464 return r;
467 } else {
468 __le32 le_rc = cpu_to_le32(ref_count);
470 sm_set_bitmap(bm_le, bit, 3);
471 dm_tm_unlock(ll->tm, nb);
473 __dm_bless_for_disk(&le_rc);
474 r = dm_btree_insert(&ll->ref_count_info, ll->ref_count_root,
475 &b, &le_rc, &ll->ref_count_root);
476 if (r < 0) {
477 DMERR("ref count insert failed");
478 return r;
482 if (ref_count && !old) {
483 *ev = SM_ALLOC;
484 ll->nr_allocated++;
485 le32_add_cpu(&ie_disk.nr_free, -1);
486 if (le32_to_cpu(ie_disk.none_free_before) == bit)
487 ie_disk.none_free_before = cpu_to_le32(bit + 1);
489 } else if (old && !ref_count) {
490 *ev = SM_FREE;
491 ll->nr_allocated--;
492 le32_add_cpu(&ie_disk.nr_free, 1);
493 ie_disk.none_free_before = cpu_to_le32(min(le32_to_cpu(ie_disk.none_free_before), bit));
494 } else
495 *ev = SM_NONE;
497 return ll->save_ie(ll, index, &ie_disk);
500 static int set_ref_count(void *context, uint32_t old, uint32_t *new)
502 *new = *((uint32_t *) context);
503 return 0;
506 int sm_ll_insert(struct ll_disk *ll, dm_block_t b,
507 uint32_t ref_count, enum allocation_event *ev)
509 return sm_ll_mutate(ll, b, set_ref_count, &ref_count, ev);
512 static int inc_ref_count(void *context, uint32_t old, uint32_t *new)
514 *new = old + 1;
515 return 0;
518 int sm_ll_inc(struct ll_disk *ll, dm_block_t b, enum allocation_event *ev)
520 return sm_ll_mutate(ll, b, inc_ref_count, NULL, ev);
523 static int dec_ref_count(void *context, uint32_t old, uint32_t *new)
525 if (!old) {
526 DMERR_LIMIT("unable to decrement a reference count below 0");
527 return -EINVAL;
530 *new = old - 1;
531 return 0;
534 int sm_ll_dec(struct ll_disk *ll, dm_block_t b, enum allocation_event *ev)
536 return sm_ll_mutate(ll, b, dec_ref_count, NULL, ev);
539 int sm_ll_commit(struct ll_disk *ll)
541 int r = 0;
543 if (ll->bitmap_index_changed) {
544 r = ll->commit(ll);
545 if (!r)
546 ll->bitmap_index_changed = false;
549 return r;
552 /*----------------------------------------------------------------*/
554 static int metadata_ll_load_ie(struct ll_disk *ll, dm_block_t index,
555 struct disk_index_entry *ie)
557 memcpy(ie, ll->mi_le.index + index, sizeof(*ie));
558 return 0;
561 static int metadata_ll_save_ie(struct ll_disk *ll, dm_block_t index,
562 struct disk_index_entry *ie)
564 ll->bitmap_index_changed = true;
565 memcpy(ll->mi_le.index + index, ie, sizeof(*ie));
566 return 0;
569 static int metadata_ll_init_index(struct ll_disk *ll)
571 int r;
572 struct dm_block *b;
574 r = dm_tm_new_block(ll->tm, &index_validator, &b);
575 if (r < 0)
576 return r;
578 ll->bitmap_root = dm_block_location(b);
580 dm_tm_unlock(ll->tm, b);
582 return 0;
585 static int metadata_ll_open(struct ll_disk *ll)
587 int r;
588 struct dm_block *block;
590 r = dm_tm_read_lock(ll->tm, ll->bitmap_root,
591 &index_validator, &block);
592 if (r)
593 return r;
595 memcpy(&ll->mi_le, dm_block_data(block), sizeof(ll->mi_le));
596 dm_tm_unlock(ll->tm, block);
598 return 0;
601 static dm_block_t metadata_ll_max_entries(struct ll_disk *ll)
603 return MAX_METADATA_BITMAPS;
606 static int metadata_ll_commit(struct ll_disk *ll)
608 int r, inc;
609 struct dm_block *b;
611 r = dm_tm_shadow_block(ll->tm, ll->bitmap_root, &index_validator, &b, &inc);
612 if (r)
613 return r;
615 memcpy(dm_block_data(b), &ll->mi_le, sizeof(ll->mi_le));
616 ll->bitmap_root = dm_block_location(b);
618 dm_tm_unlock(ll->tm, b);
620 return 0;
623 int sm_ll_new_metadata(struct ll_disk *ll, struct dm_transaction_manager *tm)
625 int r;
627 r = sm_ll_init(ll, tm);
628 if (r < 0)
629 return r;
631 ll->load_ie = metadata_ll_load_ie;
632 ll->save_ie = metadata_ll_save_ie;
633 ll->init_index = metadata_ll_init_index;
634 ll->open_index = metadata_ll_open;
635 ll->max_entries = metadata_ll_max_entries;
636 ll->commit = metadata_ll_commit;
638 ll->nr_blocks = 0;
639 ll->nr_allocated = 0;
641 r = ll->init_index(ll);
642 if (r < 0)
643 return r;
645 r = dm_btree_empty(&ll->ref_count_info, &ll->ref_count_root);
646 if (r < 0)
647 return r;
649 return 0;
652 int sm_ll_open_metadata(struct ll_disk *ll, struct dm_transaction_manager *tm,
653 void *root_le, size_t len)
655 int r;
656 struct disk_sm_root smr;
658 if (len < sizeof(struct disk_sm_root)) {
659 DMERR("sm_metadata root too small");
660 return -ENOMEM;
664 * We don't know the alignment of the root_le buffer, so need to
665 * copy into a new structure.
667 memcpy(&smr, root_le, sizeof(smr));
669 r = sm_ll_init(ll, tm);
670 if (r < 0)
671 return r;
673 ll->load_ie = metadata_ll_load_ie;
674 ll->save_ie = metadata_ll_save_ie;
675 ll->init_index = metadata_ll_init_index;
676 ll->open_index = metadata_ll_open;
677 ll->max_entries = metadata_ll_max_entries;
678 ll->commit = metadata_ll_commit;
680 ll->nr_blocks = le64_to_cpu(smr.nr_blocks);
681 ll->nr_allocated = le64_to_cpu(smr.nr_allocated);
682 ll->bitmap_root = le64_to_cpu(smr.bitmap_root);
683 ll->ref_count_root = le64_to_cpu(smr.ref_count_root);
685 return ll->open_index(ll);
688 /*----------------------------------------------------------------*/
690 static int disk_ll_load_ie(struct ll_disk *ll, dm_block_t index,
691 struct disk_index_entry *ie)
693 return dm_btree_lookup(&ll->bitmap_info, ll->bitmap_root, &index, ie);
696 static int disk_ll_save_ie(struct ll_disk *ll, dm_block_t index,
697 struct disk_index_entry *ie)
699 __dm_bless_for_disk(ie);
700 return dm_btree_insert(&ll->bitmap_info, ll->bitmap_root,
701 &index, ie, &ll->bitmap_root);
704 static int disk_ll_init_index(struct ll_disk *ll)
706 return dm_btree_empty(&ll->bitmap_info, &ll->bitmap_root);
709 static int disk_ll_open(struct ll_disk *ll)
711 /* nothing to do */
712 return 0;
715 static dm_block_t disk_ll_max_entries(struct ll_disk *ll)
717 return -1ULL;
720 static int disk_ll_commit(struct ll_disk *ll)
722 return 0;
725 int sm_ll_new_disk(struct ll_disk *ll, struct dm_transaction_manager *tm)
727 int r;
729 r = sm_ll_init(ll, tm);
730 if (r < 0)
731 return r;
733 ll->load_ie = disk_ll_load_ie;
734 ll->save_ie = disk_ll_save_ie;
735 ll->init_index = disk_ll_init_index;
736 ll->open_index = disk_ll_open;
737 ll->max_entries = disk_ll_max_entries;
738 ll->commit = disk_ll_commit;
740 ll->nr_blocks = 0;
741 ll->nr_allocated = 0;
743 r = ll->init_index(ll);
744 if (r < 0)
745 return r;
747 r = dm_btree_empty(&ll->ref_count_info, &ll->ref_count_root);
748 if (r < 0)
749 return r;
751 return 0;
754 int sm_ll_open_disk(struct ll_disk *ll, struct dm_transaction_manager *tm,
755 void *root_le, size_t len)
757 int r;
758 struct disk_sm_root *smr = root_le;
760 if (len < sizeof(struct disk_sm_root)) {
761 DMERR("sm_metadata root too small");
762 return -ENOMEM;
765 r = sm_ll_init(ll, tm);
766 if (r < 0)
767 return r;
769 ll->load_ie = disk_ll_load_ie;
770 ll->save_ie = disk_ll_save_ie;
771 ll->init_index = disk_ll_init_index;
772 ll->open_index = disk_ll_open;
773 ll->max_entries = disk_ll_max_entries;
774 ll->commit = disk_ll_commit;
776 ll->nr_blocks = le64_to_cpu(smr->nr_blocks);
777 ll->nr_allocated = le64_to_cpu(smr->nr_allocated);
778 ll->bitmap_root = le64_to_cpu(smr->bitmap_root);
779 ll->ref_count_root = le64_to_cpu(smr->ref_count_root);
781 return ll->open_index(ll);
784 /*----------------------------------------------------------------*/