drivers/md/persistent-data/dm-space-map-common.c

   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
  10 #include <linux/bitops.h>
  11 #include <linux/device-mapper.h>
  12
  13 #define DM_MSG_PREFIX "space map common"
  14
  15 /*----------------------------------------------------------------*/
  16
  17 /*
  18  * Index validator.
  19  */
  20 #define INDEX_CSUM_XOR 160478
  21
  22 static void index_prepare_for_write(struct dm_block_validator *v,
  23                                     struct dm_block *b,
  24                                     size_t block_size)
  25 {
  26         struct disk_metadata_index *mi_le = dm_block_data(b);
  27
  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));
  32 }
  33
  34 static int index_check(struct dm_block_validator *v,
  35                        struct dm_block *b,
  36                        size_t block_size)
  37 {
  38         struct disk_metadata_index *mi_le = dm_block_data(b);
  39         __le32 csum_disk;
  40
  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;
  45         }
  46
  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;
  54         }
  55
  56         return 0;
  57 }
  58
  59 static struct dm_block_validator index_validator = {
  60         .name = "index",
  61         .prepare_for_write = index_prepare_for_write,
  62         .check = index_check
  63 };
  64
  65 /*----------------------------------------------------------------*/
  66
  67 /*
  68  * Bitmap validator
  69  */
  70 #define BITMAP_CSUM_XOR 240779
  71
  72 static void bitmap_prepare_for_write(struct dm_block_validator *v,
  73                                      struct dm_block *b,
  74                                      size_t block_size)
  75 {
  76         struct disk_bitmap_header *disk_header = dm_block_data(b);
  77
  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));
  82 }
  83
  84 static int bitmap_check(struct dm_block_validator *v,
  85                         struct dm_block *b,
  86                         size_t block_size)
  87 {
  88         struct disk_bitmap_header *disk_header = dm_block_data(b);
  89         __le32 csum_disk;
  90
  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;
  95         }
  96
  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;
 104         }
 105
 106         return 0;
 107 }
 108
 109 static struct dm_block_validator dm_sm_bitmap_validator = {
 110         .name = "sm_bitmap",
 111         .prepare_for_write = bitmap_prepare_for_write,
 112         .check = bitmap_check
 113 };
 114
 115 /*----------------------------------------------------------------*/
 116
 117 #define ENTRIES_PER_WORD 32
 118 #define ENTRIES_SHIFT   5
 119
 120 static void *dm_bitmap_data(struct dm_block *b)
 121 {
 122         return dm_block_data(b) + sizeof(struct disk_bitmap_header);
 123 }
 124
 125 #define WORD_MASK_HIGH 0xAAAAAAAAAAAAAAAAULL
 126
 127 static unsigned bitmap_word_used(void *addr, unsigned b)
 128 {
 129         __le64 *words_le = addr;
 130         __le64 *w_le = words_le + (b >> ENTRIES_SHIFT);
 131
 132         uint64_t bits = le64_to_cpu(*w_le);
 133         uint64_t mask = (bits + WORD_MASK_HIGH + 1) & WORD_MASK_HIGH;
 134
 135         return !(~bits & mask);
 136 }
 137
 138 static unsigned sm_lookup_bitmap(void *addr, unsigned b)
 139 {
 140         __le64 *words_le = addr;
 141         __le64 *w_le = words_le + (b >> ENTRIES_SHIFT);
 142         unsigned hi, lo;
 143
 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;
 148 }
 149
 150 static void sm_set_bitmap(void *addr, unsigned b, unsigned val)
 151 {
 152         __le64 *words_le = addr;
 153         __le64 *w_le = words_le + (b >> ENTRIES_SHIFT);
 154
 155         b = (b & (ENTRIES_PER_WORD - 1)) << 1;
 156
 157         if (val & 2)
 158                 __set_bit_le(b, (void *) w_le);
 159         else
 160                 __clear_bit_le(b, (void *) w_le);
 161
 162         if (val & 1)
 163                 __set_bit_le(b + 1, (void *) w_le);
 164         else
 165                 __clear_bit_le(b + 1, (void *) w_le);
 166 }
 167
 168 static int sm_find_free(void *addr, unsigned begin, unsigned end,
 169                         unsigned *result)
 170 {
 171         while (begin < end) {
 172                 if (!(begin & (ENTRIES_PER_WORD - 1)) &&
 173                     bitmap_word_used(addr, begin)) {
 174                         begin += ENTRIES_PER_WORD;
 175                         continue;
 176                 }
 177
 178                 if (!sm_lookup_bitmap(addr, begin)) {
 179                         *result = begin;
 180                         return 0;
 181                 }
 182
 183                 begin++;
 184         }
 185
 186         return -ENOSPC;
 187 }
 188
 189 /*----------------------------------------------------------------*/
 190
 191 static int sm_ll_init(struct ll_disk *ll, struct dm_transaction_manager *tm)
 192 {
 193         ll->tm = tm;
 194
 195         ll->bitmap_info.tm = tm;
 196         ll->bitmap_info.levels = 1;
 197
 198         /*
 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.
 202          */
 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;
 207
 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;
 214
 215         ll->block_size = dm_bm_block_size(dm_tm_get_bm(tm));
 216
 217         if (ll->block_size > (1 << 30)) {
 218                 DMERR("block size too big to hold bitmaps");
 219                 return -EINVAL;
 220         }
 221
 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;
 228
 229         return 0;
 230 }
 231
 232 int sm_ll_extend(struct ll_disk *ll, dm_block_t extra_blocks)
 233 {
 234         int r;
 235         dm_block_t i, nr_blocks, nr_indexes;
 236         unsigned old_blocks, blocks;
 237
 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);
 241
 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;
 246         }
 247
 248         /*
 249          * We need to set this before the dm_tm_new_block() call below.
 250          */
 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;
 255
 256                 r = dm_tm_new_block(ll->tm, &dm_sm_bitmap_validator, &b);
 257                 if (r < 0)
 258                         return r;
 259
 260                 idx.blocknr = cpu_to_le64(dm_block_location(b));
 261
 262                 r = dm_tm_unlock(ll->tm, b);
 263                 if (r < 0)
 264                         return r;
 265
 266                 idx.nr_free = cpu_to_le32(ll->entries_per_block);
 267                 idx.none_free_before = 0;
 268
 269                 r = ll->save_ie(ll, i, &idx);
 270                 if (r < 0)
 271                         return r;
 272         }
 273
 274         return 0;
 275 }
 276
 277 int sm_ll_lookup_bitmap(struct ll_disk *ll, dm_block_t b, uint32_t *result)
 278 {
 279         int r;
 280         dm_block_t index = b;
 281         struct disk_index_entry ie_disk;
 282         struct dm_block *blk;
 283
 284         b = do_div(index, ll->entries_per_block);
 285         r = ll->load_ie(ll, index, &ie_disk);
 286         if (r < 0)
 287                 return r;
 288
 289         r = dm_tm_read_lock(ll->tm, le64_to_cpu(ie_disk.blocknr),
 290                             &dm_sm_bitmap_validator, &blk);
 291         if (r < 0)
 292                 return r;
 293
 294         *result = sm_lookup_bitmap(dm_bitmap_data(blk), b);
 295
 296         return dm_tm_unlock(ll->tm, blk);
 297 }
 298
 299 static int sm_ll_lookup_big_ref_count(struct ll_disk *ll, dm_block_t b,
 300                                       uint32_t *result)
 301 {
 302         __le32 le_rc;
 303         int r;
 304
 305         r = dm_btree_lookup(&ll->ref_count_info, ll->ref_count_root, &b, &le_rc);
 306         if (r < 0)
 307                 return r;
 308
 309         *result = le32_to_cpu(le_rc);
 310
 311         return r;
 312 }
 313
 314 int sm_ll_lookup(struct ll_disk *ll, dm_block_t b, uint32_t *result)
 315 {
 316         int r = sm_ll_lookup_bitmap(ll, b, result);
 317
 318         if (r)
 319                 return r;
 320
 321         if (*result != 3)
 322                 return r;
 323
 324         return sm_ll_lookup_big_ref_count(ll, b, result);
 325 }
 326
 327 int sm_ll_find_free_block(struct ll_disk *ll, dm_block_t begin,
 328                           dm_block_t end, dm_block_t *result)
 329 {
 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);
 334
 335         /*
 336          * FIXME: Use shifts
 337          */
 338         begin = do_div(index_begin, ll->entries_per_block);
 339         end = do_div(end, ll->entries_per_block);
 340
 341         for (i = index_begin; i < index_end; i++, begin = 0) {
 342                 struct dm_block *blk;
 343                 unsigned position;
 344                 uint32_t bit_end;
 345
 346                 r = ll->load_ie(ll, i, &ie_disk);
 347                 if (r < 0)
 348                         return r;
 349
 350                 if (le32_to_cpu(ie_disk.nr_free) == 0)
 351                         continue;
 352
 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;
 357
 358                 bit_end = (i == index_end - 1) ?  end : ll->entries_per_block;
 359
 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) {
 364                         /*
 365                          * This might happen because we started searching
 366                          * part way through the bitmap.
 367                          */
 368                         dm_tm_unlock(ll->tm, blk);
 369                         continue;
 370
 371                 } else if (r < 0) {
 372                         dm_tm_unlock(ll->tm, blk);
 373                         return r;
 374                 }
 375
 376                 r = dm_tm_unlock(ll->tm, blk);
 377                 if (r < 0)
 378                         return r;
 379
 380                 *result = i * ll->entries_per_block + (dm_block_t) position;
 381                 return 0;
 382         }
 383
 384         return -ENOSPC;
 385 }
 386
 387 static int sm_ll_mutate(struct ll_disk *ll, dm_block_t b,
 388                         int (*mutator)(void *context, uint32_t old, uint32_t *new),
 389                         void *context, enum allocation_event *ev)
 390 {
 391         int r;
 392         uint32_t bit, old, ref_count;
 393         struct dm_block *nb;
 394         dm_block_t index = b;
 395         struct disk_index_entry ie_disk;
 396         void *bm_le;
 397         int inc;
 398
 399         bit = do_div(index, ll->entries_per_block);
 400         r = ll->load_ie(ll, index, &ie_disk);
 401         if (r < 0)
 402                 return r;
 403
 404         r = dm_tm_shadow_block(ll->tm, le64_to_cpu(ie_disk.blocknr),
 405                                &dm_sm_bitmap_validator, &nb, &inc);
 406         if (r < 0) {
 407                 DMERR("dm_tm_shadow_block() failed");
 408                 return r;
 409         }
 410         ie_disk.blocknr = cpu_to_le64(dm_block_location(nb));
 411
 412         bm_le = dm_bitmap_data(nb);
 413         old = sm_lookup_bitmap(bm_le, bit);
 414
 415         if (old > 2) {
 416                 r = sm_ll_lookup_big_ref_count(ll, b, &old);
 417                 if (r < 0) {
 418                         dm_tm_unlock(ll->tm, nb);
 419                         return r;
 420                 }
 421         }
 422
 423         r = mutator(context, old, &ref_count);
 424         if (r) {
 425                 dm_tm_unlock(ll->tm, nb);
 426                 return r;
 427         }
 428
 429         if (ref_count <= 2) {
 430                 sm_set_bitmap(bm_le, bit, ref_count);
 431
 432                 r = dm_tm_unlock(ll->tm, nb);
 433                 if (r < 0)
 434                         return r;
 435
 436                 if (old > 2) {
 437                         r = dm_btree_remove(&ll->ref_count_info,
 438                                             ll->ref_count_root,
 439                                             &b, &ll->ref_count_root);
 440                         if (r)
 441                                 return r;
 442                 }
 443
 444         } else {
 445                 __le32 le_rc = cpu_to_le32(ref_count);
 446
 447                 sm_set_bitmap(bm_le, bit, 3);
 448                 r = dm_tm_unlock(ll->tm, nb);
 449                 if (r < 0)
 450                         return r;
 451
 452                 __dm_bless_for_disk(&le_rc);
 453                 r = dm_btree_insert(&ll->ref_count_info, ll->ref_count_root,
 454                                     &b, &le_rc, &ll->ref_count_root);
 455                 if (r < 0) {
 456                         DMERR("ref count insert failed");
 457                         return r;
 458                 }
 459         }
 460
 461         if (ref_count && !old) {
 462                 *ev = SM_ALLOC;
 463                 ll->nr_allocated++;
 464                 le32_add_cpu(&ie_disk.nr_free, -1);
 465                 if (le32_to_cpu(ie_disk.none_free_before) == bit)
 466                         ie_disk.none_free_before = cpu_to_le32(bit + 1);
 467
 468         } else if (old && !ref_count) {
 469                 *ev = SM_FREE;
 470                 ll->nr_allocated--;
 471                 le32_add_cpu(&ie_disk.nr_free, 1);
 472                 ie_disk.none_free_before = cpu_to_le32(min(le32_to_cpu(ie_disk.none_free_before), bit));
 473         }
 474
 475         return ll->save_ie(ll, index, &ie_disk);
 476 }
 477
 478 static int set_ref_count(void *context, uint32_t old, uint32_t *new)
 479 {
 480         *new = *((uint32_t *) context);
 481         return 0;
 482 }
 483
 484 int sm_ll_insert(struct ll_disk *ll, dm_block_t b,
 485                  uint32_t ref_count, enum allocation_event *ev)
 486 {
 487         return sm_ll_mutate(ll, b, set_ref_count, &ref_count, ev);
 488 }
 489
 490 static int inc_ref_count(void *context, uint32_t old, uint32_t *new)
 491 {
 492         *new = old + 1;
 493         return 0;
 494 }
 495
 496 int sm_ll_inc(struct ll_disk *ll, dm_block_t b, enum allocation_event *ev)
 497 {
 498         return sm_ll_mutate(ll, b, inc_ref_count, NULL, ev);
 499 }
 500
 501 static int dec_ref_count(void *context, uint32_t old, uint32_t *new)
 502 {
 503         if (!old) {
 504                 DMERR_LIMIT("unable to decrement a reference count below 0");
 505                 return -EINVAL;
 506         }
 507
 508         *new = old - 1;
 509         return 0;
 510 }
 511
 512 int sm_ll_dec(struct ll_disk *ll, dm_block_t b, enum allocation_event *ev)
 513 {
 514         return sm_ll_mutate(ll, b, dec_ref_count, NULL, ev);
 515 }
 516
 517 int sm_ll_commit(struct ll_disk *ll)
 518 {
 519         int r = 0;
 520
 521         if (ll->bitmap_index_changed) {
 522                 r = ll->commit(ll);
 523                 if (!r)
 524                         ll->bitmap_index_changed = false;
 525         }
 526
 527         return r;
 528 }
 529
 530 /*----------------------------------------------------------------*/
 531
 532 static int metadata_ll_load_ie(struct ll_disk *ll, dm_block_t index,
 533                                struct disk_index_entry *ie)
 534 {
 535         memcpy(ie, ll->mi_le.index + index, sizeof(*ie));
 536         return 0;
 537 }
 538
 539 static int metadata_ll_save_ie(struct ll_disk *ll, dm_block_t index,
 540                                struct disk_index_entry *ie)
 541 {
 542         ll->bitmap_index_changed = true;
 543         memcpy(ll->mi_le.index + index, ie, sizeof(*ie));
 544         return 0;
 545 }
 546
 547 static int metadata_ll_init_index(struct ll_disk *ll)
 548 {
 549         int r;
 550         struct dm_block *b;
 551
 552         r = dm_tm_new_block(ll->tm, &index_validator, &b);
 553         if (r < 0)
 554                 return r;
 555
 556         memcpy(dm_block_data(b), &ll->mi_le, sizeof(ll->mi_le));
 557         ll->bitmap_root = dm_block_location(b);
 558
 559         return dm_tm_unlock(ll->tm, b);
 560 }
 561
 562 static int metadata_ll_open(struct ll_disk *ll)
 563 {
 564         int r;
 565         struct dm_block *block;
 566
 567         r = dm_tm_read_lock(ll->tm, ll->bitmap_root,
 568                             &index_validator, &block);
 569         if (r)
 570                 return r;
 571
 572         memcpy(&ll->mi_le, dm_block_data(block), sizeof(ll->mi_le));
 573         return dm_tm_unlock(ll->tm, block);
 574 }
 575
 576 static dm_block_t metadata_ll_max_entries(struct ll_disk *ll)
 577 {
 578         return MAX_METADATA_BITMAPS;
 579 }
 580
 581 static int metadata_ll_commit(struct ll_disk *ll)
 582 {
 583         int r, inc;
 584         struct dm_block *b;
 585
 586         r = dm_tm_shadow_block(ll->tm, ll->bitmap_root, &index_validator, &b, &inc);
 587         if (r)
 588                 return r;
 589
 590         memcpy(dm_block_data(b), &ll->mi_le, sizeof(ll->mi_le));
 591         ll->bitmap_root = dm_block_location(b);
 592
 593         return dm_tm_unlock(ll->tm, b);
 594 }
 595
 596 int sm_ll_new_metadata(struct ll_disk *ll, struct dm_transaction_manager *tm)
 597 {
 598         int r;
 599
 600         r = sm_ll_init(ll, tm);
 601         if (r < 0)
 602                 return r;
 603
 604         ll->load_ie = metadata_ll_load_ie;
 605         ll->save_ie = metadata_ll_save_ie;
 606         ll->init_index = metadata_ll_init_index;
 607         ll->open_index = metadata_ll_open;
 608         ll->max_entries = metadata_ll_max_entries;
 609         ll->commit = metadata_ll_commit;
 610
 611         ll->nr_blocks = 0;
 612         ll->nr_allocated = 0;
 613
 614         r = ll->init_index(ll);
 615         if (r < 0)
 616                 return r;
 617
 618         r = dm_btree_empty(&ll->ref_count_info, &ll->ref_count_root);
 619         if (r < 0)
 620                 return r;
 621
 622         return 0;
 623 }
 624
 625 int sm_ll_open_metadata(struct ll_disk *ll, struct dm_transaction_manager *tm,
 626                         void *root_le, size_t len)
 627 {
 628         int r;
 629         struct disk_sm_root *smr = root_le;
 630
 631         if (len < sizeof(struct disk_sm_root)) {
 632                 DMERR("sm_metadata root too small");
 633                 return -ENOMEM;
 634         }
 635
 636         r = sm_ll_init(ll, tm);
 637         if (r < 0)
 638                 return r;
 639
 640         ll->load_ie = metadata_ll_load_ie;
 641         ll->save_ie = metadata_ll_save_ie;
 642         ll->init_index = metadata_ll_init_index;
 643         ll->open_index = metadata_ll_open;
 644         ll->max_entries = metadata_ll_max_entries;
 645         ll->commit = metadata_ll_commit;
 646
 647         ll->nr_blocks = le64_to_cpu(smr->nr_blocks);
 648         ll->nr_allocated = le64_to_cpu(smr->nr_allocated);
 649         ll->bitmap_root = le64_to_cpu(smr->bitmap_root);
 650         ll->ref_count_root = le64_to_cpu(smr->ref_count_root);
 651
 652         return ll->open_index(ll);
 653 }
 654
 655 /*----------------------------------------------------------------*/
 656
 657 static int disk_ll_load_ie(struct ll_disk *ll, dm_block_t index,
 658                            struct disk_index_entry *ie)
 659 {
 660         return dm_btree_lookup(&ll->bitmap_info, ll->bitmap_root, &index, ie);
 661 }
 662
 663 static int disk_ll_save_ie(struct ll_disk *ll, dm_block_t index,
 664                            struct disk_index_entry *ie)
 665 {
 666         __dm_bless_for_disk(ie);
 667         return dm_btree_insert(&ll->bitmap_info, ll->bitmap_root,
 668                                &index, ie, &ll->bitmap_root);
 669 }
 670
 671 static int disk_ll_init_index(struct ll_disk *ll)
 672 {
 673         return dm_btree_empty(&ll->bitmap_info, &ll->bitmap_root);
 674 }
 675
 676 static int disk_ll_open(struct ll_disk *ll)
 677 {
 678         /* nothing to do */
 679         return 0;
 680 }
 681
 682 static dm_block_t disk_ll_max_entries(struct ll_disk *ll)
 683 {
 684         return -1ULL;
 685 }
 686
 687 static int disk_ll_commit(struct ll_disk *ll)
 688 {
 689         return 0;
 690 }
 691
 692 int sm_ll_new_disk(struct ll_disk *ll, struct dm_transaction_manager *tm)
 693 {
 694         int r;
 695
 696         r = sm_ll_init(ll, tm);
 697         if (r < 0)
 698                 return r;
 699
 700         ll->load_ie = disk_ll_load_ie;
 701         ll->save_ie = disk_ll_save_ie;
 702         ll->init_index = disk_ll_init_index;
 703         ll->open_index = disk_ll_open;
 704         ll->max_entries = disk_ll_max_entries;
 705         ll->commit = disk_ll_commit;
 706
 707         ll->nr_blocks = 0;
 708         ll->nr_allocated = 0;
 709
 710         r = ll->init_index(ll);
 711         if (r < 0)
 712                 return r;
 713
 714         r = dm_btree_empty(&ll->ref_count_info, &ll->ref_count_root);
 715         if (r < 0)
 716                 return r;
 717
 718         return 0;
 719 }
 720
 721 int sm_ll_open_disk(struct ll_disk *ll, struct dm_transaction_manager *tm,
 722                     void *root_le, size_t len)
 723 {
 724         int r;
 725         struct disk_sm_root *smr = root_le;
 726
 727         if (len < sizeof(struct disk_sm_root)) {
 728                 DMERR("sm_metadata root too small");
 729                 return -ENOMEM;
 730         }
 731
 732         r = sm_ll_init(ll, tm);
 733         if (r < 0)
 734                 return r;
 735
 736         ll->load_ie = disk_ll_load_ie;
 737         ll->save_ie = disk_ll_save_ie;
 738         ll->init_index = disk_ll_init_index;
 739         ll->open_index = disk_ll_open;
 740         ll->max_entries = disk_ll_max_entries;
 741         ll->commit = disk_ll_commit;
 742
 743         ll->nr_blocks = le64_to_cpu(smr->nr_blocks);
 744         ll->nr_allocated = le64_to_cpu(smr->nr_allocated);
 745         ll->bitmap_root = le64_to_cpu(smr->bitmap_root);
 746         ll->ref_count_root = le64_to_cpu(smr->ref_count_root);
 747
 748         return ll->open_index(ll);
 749 }
 750
 751 /*----------------------------------------------------------------*/