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 int sm_ll_lookup(struct ll_disk *ll, dm_block_t b, uint32_t *result)
 300 {
 301         __le32 le_rc;
 302         int r = sm_ll_lookup_bitmap(ll, b, result);
 303
 304         if (r)
 305                 return r;
 306
 307         if (*result != 3)
 308                 return r;
 309
 310         r = dm_btree_lookup(&ll->ref_count_info, ll->ref_count_root, &b, &le_rc);
 311         if (r < 0)
 312                 return r;
 313
 314         *result = le32_to_cpu(le_rc);
 315
 316         return r;
 317 }
 318
 319 int sm_ll_find_free_block(struct ll_disk *ll, dm_block_t begin,
 320                           dm_block_t end, dm_block_t *result)
 321 {
 322         int r;
 323         struct disk_index_entry ie_disk;
 324         dm_block_t i, index_begin = begin;
 325         dm_block_t index_end = dm_sector_div_up(end, ll->entries_per_block);
 326
 327         /*
 328          * FIXME: Use shifts
 329          */
 330         begin = do_div(index_begin, ll->entries_per_block);
 331         end = do_div(end, ll->entries_per_block);
 332
 333         for (i = index_begin; i < index_end; i++, begin = 0) {
 334                 struct dm_block *blk;
 335                 unsigned position;
 336                 uint32_t bit_end;
 337
 338                 r = ll->load_ie(ll, i, &ie_disk);
 339                 if (r < 0)
 340                         return r;
 341
 342                 if (le32_to_cpu(ie_disk.nr_free) == 0)
 343                         continue;
 344
 345                 r = dm_tm_read_lock(ll->tm, le64_to_cpu(ie_disk.blocknr),
 346                                     &dm_sm_bitmap_validator, &blk);
 347                 if (r < 0)
 348                         return r;
 349
 350                 bit_end = (i == index_end - 1) ?  end : ll->entries_per_block;
 351
 352                 r = sm_find_free(dm_bitmap_data(blk),
 353                                  max_t(unsigned, begin, le32_to_cpu(ie_disk.none_free_before)),
 354                                  bit_end, &position);
 355                 if (r == -ENOSPC) {
 356                         /*
 357                          * This might happen because we started searching
 358                          * part way through the bitmap.
 359                          */
 360                         dm_tm_unlock(ll->tm, blk);
 361                         continue;
 362
 363                 } else if (r < 0) {
 364                         dm_tm_unlock(ll->tm, blk);
 365                         return r;
 366                 }
 367
 368                 r = dm_tm_unlock(ll->tm, blk);
 369                 if (r < 0)
 370                         return r;
 371
 372                 *result = i * ll->entries_per_block + (dm_block_t) position;
 373                 return 0;
 374         }
 375
 376         return -ENOSPC;
 377 }
 378
 379 int sm_ll_insert(struct ll_disk *ll, dm_block_t b,
 380                  uint32_t ref_count, enum allocation_event *ev)
 381 {
 382         int r;
 383         uint32_t bit, old;
 384         struct dm_block *nb;
 385         dm_block_t index = b;
 386         struct disk_index_entry ie_disk;
 387         void *bm_le;
 388         int inc;
 389
 390         bit = do_div(index, ll->entries_per_block);
 391         r = ll->load_ie(ll, index, &ie_disk);
 392         if (r < 0)
 393                 return r;
 394
 395         r = dm_tm_shadow_block(ll->tm, le64_to_cpu(ie_disk.blocknr),
 396                                &dm_sm_bitmap_validator, &nb, &inc);
 397         if (r < 0) {
 398                 DMERR("dm_tm_shadow_block() failed");
 399                 return r;
 400         }
 401         ie_disk.blocknr = cpu_to_le64(dm_block_location(nb));
 402
 403         bm_le = dm_bitmap_data(nb);
 404         old = sm_lookup_bitmap(bm_le, bit);
 405
 406         if (ref_count <= 2) {
 407                 sm_set_bitmap(bm_le, bit, ref_count);
 408
 409                 r = dm_tm_unlock(ll->tm, nb);
 410                 if (r < 0)
 411                         return r;
 412
 413                 if (old > 2) {
 414                         r = dm_btree_remove(&ll->ref_count_info,
 415                                             ll->ref_count_root,
 416                                             &b, &ll->ref_count_root);
 417                         if (r)
 418                                 return r;
 419                 }
 420
 421         } else {
 422                 __le32 le_rc = cpu_to_le32(ref_count);
 423
 424                 sm_set_bitmap(bm_le, bit, 3);
 425                 r = dm_tm_unlock(ll->tm, nb);
 426                 if (r < 0)
 427                         return r;
 428
 429                 __dm_bless_for_disk(&le_rc);
 430                 r = dm_btree_insert(&ll->ref_count_info, ll->ref_count_root,
 431                                     &b, &le_rc, &ll->ref_count_root);
 432                 if (r < 0) {
 433                         DMERR("ref count insert failed");
 434                         return r;
 435                 }
 436         }
 437
 438         if (ref_count && !old) {
 439                 *ev = SM_ALLOC;
 440                 ll->nr_allocated++;
 441                 le32_add_cpu(&ie_disk.nr_free, -1);
 442                 if (le32_to_cpu(ie_disk.none_free_before) == bit)
 443                         ie_disk.none_free_before = cpu_to_le32(bit + 1);
 444
 445         } else if (old && !ref_count) {
 446                 *ev = SM_FREE;
 447                 ll->nr_allocated--;
 448                 le32_add_cpu(&ie_disk.nr_free, 1);
 449                 ie_disk.none_free_before = cpu_to_le32(min(le32_to_cpu(ie_disk.none_free_before), bit));
 450         }
 451
 452         return ll->save_ie(ll, index, &ie_disk);
 453 }
 454
 455 int sm_ll_inc(struct ll_disk *ll, dm_block_t b, enum allocation_event *ev)
 456 {
 457         int r;
 458         uint32_t rc;
 459
 460         r = sm_ll_lookup(ll, b, &rc);
 461         if (r)
 462                 return r;
 463
 464         return sm_ll_insert(ll, b, rc + 1, ev);
 465 }
 466
 467 int sm_ll_dec(struct ll_disk *ll, dm_block_t b, enum allocation_event *ev)
 468 {
 469         int r;
 470         uint32_t rc;
 471
 472         r = sm_ll_lookup(ll, b, &rc);
 473         if (r)
 474                 return r;
 475
 476         if (!rc)
 477                 return -EINVAL;
 478
 479         return sm_ll_insert(ll, b, rc - 1, ev);
 480 }
 481
 482 int sm_ll_commit(struct ll_disk *ll)
 483 {
 484         int r = 0;
 485
 486         if (ll->bitmap_index_changed) {
 487                 r = ll->commit(ll);
 488                 if (!r)
 489                         ll->bitmap_index_changed = false;
 490         }
 491
 492         return r;
 493 }
 494
 495 /*----------------------------------------------------------------*/
 496
 497 static int metadata_ll_load_ie(struct ll_disk *ll, dm_block_t index,
 498                                struct disk_index_entry *ie)
 499 {
 500         memcpy(ie, ll->mi_le.index + index, sizeof(*ie));
 501         return 0;
 502 }
 503
 504 static int metadata_ll_save_ie(struct ll_disk *ll, dm_block_t index,
 505                                struct disk_index_entry *ie)
 506 {
 507         ll->bitmap_index_changed = true;
 508         memcpy(ll->mi_le.index + index, ie, sizeof(*ie));
 509         return 0;
 510 }
 511
 512 static int metadata_ll_init_index(struct ll_disk *ll)
 513 {
 514         int r;
 515         struct dm_block *b;
 516
 517         r = dm_tm_new_block(ll->tm, &index_validator, &b);
 518         if (r < 0)
 519                 return r;
 520
 521         memcpy(dm_block_data(b), &ll->mi_le, sizeof(ll->mi_le));
 522         ll->bitmap_root = dm_block_location(b);
 523
 524         return dm_tm_unlock(ll->tm, b);
 525 }
 526
 527 static int metadata_ll_open(struct ll_disk *ll)
 528 {
 529         int r;
 530         struct dm_block *block;
 531
 532         r = dm_tm_read_lock(ll->tm, ll->bitmap_root,
 533                             &index_validator, &block);
 534         if (r)
 535                 return r;
 536
 537         memcpy(&ll->mi_le, dm_block_data(block), sizeof(ll->mi_le));
 538         return dm_tm_unlock(ll->tm, block);
 539 }
 540
 541 static dm_block_t metadata_ll_max_entries(struct ll_disk *ll)
 542 {
 543         return MAX_METADATA_BITMAPS;
 544 }
 545
 546 static int metadata_ll_commit(struct ll_disk *ll)
 547 {
 548         int r, inc;
 549         struct dm_block *b;
 550
 551         r = dm_tm_shadow_block(ll->tm, ll->bitmap_root, &index_validator, &b, &inc);
 552         if (r)
 553                 return r;
 554
 555         memcpy(dm_block_data(b), &ll->mi_le, sizeof(ll->mi_le));
 556         ll->bitmap_root = dm_block_location(b);
 557
 558         return dm_tm_unlock(ll->tm, b);
 559 }
 560
 561 int sm_ll_new_metadata(struct ll_disk *ll, struct dm_transaction_manager *tm)
 562 {
 563         int r;
 564
 565         r = sm_ll_init(ll, tm);
 566         if (r < 0)
 567                 return r;
 568
 569         ll->load_ie = metadata_ll_load_ie;
 570         ll->save_ie = metadata_ll_save_ie;
 571         ll->init_index = metadata_ll_init_index;
 572         ll->open_index = metadata_ll_open;
 573         ll->max_entries = metadata_ll_max_entries;
 574         ll->commit = metadata_ll_commit;
 575
 576         ll->nr_blocks = 0;
 577         ll->nr_allocated = 0;
 578
 579         r = ll->init_index(ll);
 580         if (r < 0)
 581                 return r;
 582
 583         r = dm_btree_empty(&ll->ref_count_info, &ll->ref_count_root);
 584         if (r < 0)
 585                 return r;
 586
 587         return 0;
 588 }
 589
 590 int sm_ll_open_metadata(struct ll_disk *ll, struct dm_transaction_manager *tm,
 591                         void *root_le, size_t len)
 592 {
 593         int r;
 594         struct disk_sm_root *smr = root_le;
 595
 596         if (len < sizeof(struct disk_sm_root)) {
 597                 DMERR("sm_metadata root too small");
 598                 return -ENOMEM;
 599         }
 600
 601         r = sm_ll_init(ll, tm);
 602         if (r < 0)
 603                 return r;
 604
 605         ll->load_ie = metadata_ll_load_ie;
 606         ll->save_ie = metadata_ll_save_ie;
 607         ll->init_index = metadata_ll_init_index;
 608         ll->open_index = metadata_ll_open;
 609         ll->max_entries = metadata_ll_max_entries;
 610         ll->commit = metadata_ll_commit;
 611
 612         ll->nr_blocks = le64_to_cpu(smr->nr_blocks);
 613         ll->nr_allocated = le64_to_cpu(smr->nr_allocated);
 614         ll->bitmap_root = le64_to_cpu(smr->bitmap_root);
 615         ll->ref_count_root = le64_to_cpu(smr->ref_count_root);
 616
 617         return ll->open_index(ll);
 618 }
 619
 620 /*----------------------------------------------------------------*/
 621
 622 static int disk_ll_load_ie(struct ll_disk *ll, dm_block_t index,
 623                            struct disk_index_entry *ie)
 624 {
 625         return dm_btree_lookup(&ll->bitmap_info, ll->bitmap_root, &index, ie);
 626 }
 627
 628 static int disk_ll_save_ie(struct ll_disk *ll, dm_block_t index,
 629                            struct disk_index_entry *ie)
 630 {
 631         __dm_bless_for_disk(ie);
 632         return dm_btree_insert(&ll->bitmap_info, ll->bitmap_root,
 633                                &index, ie, &ll->bitmap_root);
 634 }
 635
 636 static int disk_ll_init_index(struct ll_disk *ll)
 637 {
 638         return dm_btree_empty(&ll->bitmap_info, &ll->bitmap_root);
 639 }
 640
 641 static int disk_ll_open(struct ll_disk *ll)
 642 {
 643         /* nothing to do */
 644         return 0;
 645 }
 646
 647 static dm_block_t disk_ll_max_entries(struct ll_disk *ll)
 648 {
 649         return -1ULL;
 650 }
 651
 652 static int disk_ll_commit(struct ll_disk *ll)
 653 {
 654         return 0;
 655 }
 656
 657 int sm_ll_new_disk(struct ll_disk *ll, struct dm_transaction_manager *tm)
 658 {
 659         int r;
 660
 661         r = sm_ll_init(ll, tm);
 662         if (r < 0)
 663                 return r;
 664
 665         ll->load_ie = disk_ll_load_ie;
 666         ll->save_ie = disk_ll_save_ie;
 667         ll->init_index = disk_ll_init_index;
 668         ll->open_index = disk_ll_open;
 669         ll->max_entries = disk_ll_max_entries;
 670         ll->commit = disk_ll_commit;
 671
 672         ll->nr_blocks = 0;
 673         ll->nr_allocated = 0;
 674
 675         r = ll->init_index(ll);
 676         if (r < 0)
 677                 return r;
 678
 679         r = dm_btree_empty(&ll->ref_count_info, &ll->ref_count_root);
 680         if (r < 0)
 681                 return r;
 682
 683         return 0;
 684 }
 685
 686 int sm_ll_open_disk(struct ll_disk *ll, struct dm_transaction_manager *tm,
 687                     void *root_le, size_t len)
 688 {
 689         int r;
 690         struct disk_sm_root *smr = root_le;
 691
 692         if (len < sizeof(struct disk_sm_root)) {
 693                 DMERR("sm_metadata root too small");
 694                 return -ENOMEM;
 695         }
 696
 697         r = sm_ll_init(ll, tm);
 698         if (r < 0)
 699                 return r;
 700
 701         ll->load_ie = disk_ll_load_ie;
 702         ll->save_ie = disk_ll_save_ie;
 703         ll->init_index = disk_ll_init_index;
 704         ll->open_index = disk_ll_open;
 705         ll->max_entries = disk_ll_max_entries;
 706         ll->commit = disk_ll_commit;
 707
 708         ll->nr_blocks = le64_to_cpu(smr->nr_blocks);
 709         ll->nr_allocated = le64_to_cpu(smr->nr_allocated);
 710         ll->bitmap_root = le64_to_cpu(smr->bitmap_root);
 711         ll->ref_count_root = le64_to_cpu(smr->ref_count_root);
 712
 713         return ll->open_index(ll);
 714 }
 715
 716 /*----------------------------------------------------------------*/