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                 dm_tm_unlock(ll->tm, b);
 263
 264                 idx.nr_free = cpu_to_le32(ll->entries_per_block);
 265                 idx.none_free_before = 0;
 266
 267                 r = ll->save_ie(ll, i, &idx);
 268                 if (r < 0)
 269                         return r;
 270         }
 271
 272         return 0;
 273 }
 274
 275 int sm_ll_lookup_bitmap(struct ll_disk *ll, dm_block_t b, uint32_t *result)
 276 {
 277         int r;
 278         dm_block_t index = b;
 279         struct disk_index_entry ie_disk;
 280         struct dm_block *blk;
 281
 282         if (b >= ll->nr_blocks) {
 283                 DMERR_LIMIT("metadata block out of bounds");
 284                 return -EINVAL;
 285         }
 286
 287         b = do_div(index, ll->entries_per_block);
 288         r = ll->load_ie(ll, index, &ie_disk);
 289         if (r < 0)
 290                 return r;
 291
 292         r = dm_tm_read_lock(ll->tm, le64_to_cpu(ie_disk.blocknr),
 293                             &dm_sm_bitmap_validator, &blk);
 294         if (r < 0)
 295                 return r;
 296
 297         *result = sm_lookup_bitmap(dm_bitmap_data(blk), b);
 298
 299         dm_tm_unlock(ll->tm, blk);
 300
 301         return 0;
 302 }
 303
 304 static int sm_ll_lookup_big_ref_count(struct ll_disk *ll, dm_block_t b,
 305                                       uint32_t *result)
 306 {
 307         __le32 le_rc;
 308         int 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_lookup(struct ll_disk *ll, dm_block_t b, uint32_t *result)
 320 {
 321         int r = sm_ll_lookup_bitmap(ll, b, result);
 322
 323         if (r)
 324                 return r;
 325
 326         if (*result != 3)
 327                 return r;
 328
 329         return sm_ll_lookup_big_ref_count(ll, b, result);
 330 }
 331
 332 int sm_ll_find_free_block(struct ll_disk *ll, dm_block_t begin,
 333                           dm_block_t end, dm_block_t *result)
 334 {
 335         int r;
 336         struct disk_index_entry ie_disk;
 337         dm_block_t i, index_begin = begin;
 338         dm_block_t index_end = dm_sector_div_up(end, ll->entries_per_block);
 339
 340         /*
 341          * FIXME: Use shifts
 342          */
 343         begin = do_div(index_begin, ll->entries_per_block);
 344         end = do_div(end, ll->entries_per_block);
 345         if (end == 0)
 346                 end = ll->entries_per_block;
 347
 348         for (i = index_begin; i < index_end; i++, begin = 0) {
 349                 struct dm_block *blk;
 350                 unsigned position;
 351                 uint32_t bit_end;
 352
 353                 r = ll->load_ie(ll, i, &ie_disk);
 354                 if (r < 0)
 355                         return r;
 356
 357                 if (le32_to_cpu(ie_disk.nr_free) == 0)
 358                         continue;
 359
 360                 r = dm_tm_read_lock(ll->tm, le64_to_cpu(ie_disk.blocknr),
 361                                     &dm_sm_bitmap_validator, &blk);
 362                 if (r < 0)
 363                         return r;
 364
 365                 bit_end = (i == index_end - 1) ?  end : ll->entries_per_block;
 366
 367                 r = sm_find_free(dm_bitmap_data(blk),
 368                                  max_t(unsigned, begin, le32_to_cpu(ie_disk.none_free_before)),
 369                                  bit_end, &position);
 370                 if (r == -ENOSPC) {
 371                         /*
 372                          * This might happen because we started searching
 373                          * part way through the bitmap.
 374                          */
 375                         dm_tm_unlock(ll->tm, blk);
 376                         continue;
 377
 378                 } else if (r < 0) {
 379                         dm_tm_unlock(ll->tm, blk);
 380                         return r;
 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
 392 int 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 static int sm_ll_mutate(struct ll_disk *ll, dm_block_t b,
 420                         int (*mutator)(void *context, uint32_t old, uint32_t *new),
 421                         void *context, enum allocation_event *ev)
 422 {
 423         int r;
 424         uint32_t bit, old, ref_count;
 425         struct dm_block *nb;
 426         dm_block_t index = b;
 427         struct disk_index_entry ie_disk;
 428         void *bm_le;
 429         int inc;
 430
 431         bit = do_div(index, ll->entries_per_block);
 432         r = ll->load_ie(ll, index, &ie_disk);
 433         if (r < 0)
 434                 return r;
 435
 436         r = dm_tm_shadow_block(ll->tm, le64_to_cpu(ie_disk.blocknr),
 437                                &dm_sm_bitmap_validator, &nb, &inc);
 438         if (r < 0) {
 439                 DMERR("dm_tm_shadow_block() failed");
 440                 return r;
 441         }
 442         ie_disk.blocknr = cpu_to_le64(dm_block_location(nb));
 443
 444         bm_le = dm_bitmap_data(nb);
 445         old = sm_lookup_bitmap(bm_le, bit);
 446
 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         r = mutator(context, old, &ref_count);
 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
 464                 dm_tm_unlock(ll->tm, nb);
 465
 466                 if (old > 2) {
 467                         r = dm_btree_remove(&ll->ref_count_info,
 468                                             ll->ref_count_root,
 469                                             &b, &ll->ref_count_root);
 470                         if (r)
 471                                 return r;
 472                 }
 473
 474         } else {
 475                 __le32 le_rc = cpu_to_le32(ref_count);
 476
 477                 sm_set_bitmap(bm_le, bit, 3);
 478                 dm_tm_unlock(ll->tm, nb);
 479
 480                 __dm_bless_for_disk(&le_rc);
 481                 r = dm_btree_insert(&ll->ref_count_info, ll->ref_count_root,
 482                                     &b, &le_rc, &ll->ref_count_root);
 483                 if (r < 0) {
 484                         DMERR("ref count insert failed");
 485                         return r;
 486                 }
 487         }
 488
 489         if (ref_count && !old) {
 490                 *ev = SM_ALLOC;
 491                 ll->nr_allocated++;
 492                 le32_add_cpu(&ie_disk.nr_free, -1);
 493                 if (le32_to_cpu(ie_disk.none_free_before) == bit)
 494                         ie_disk.none_free_before = cpu_to_le32(bit + 1);
 495
 496         } else if (old && !ref_count) {
 497                 *ev = SM_FREE;
 498                 ll->nr_allocated--;
 499                 le32_add_cpu(&ie_disk.nr_free, 1);
 500                 ie_disk.none_free_before = cpu_to_le32(min(le32_to_cpu(ie_disk.none_free_before), bit));
 501         }
 502
 503         return ll->save_ie(ll, index, &ie_disk);
 504 }
 505
 506 static int set_ref_count(void *context, uint32_t old, uint32_t *new)
 507 {
 508         *new = *((uint32_t *) context);
 509         return 0;
 510 }
 511
 512 int sm_ll_insert(struct ll_disk *ll, dm_block_t b,
 513                  uint32_t ref_count, enum allocation_event *ev)
 514 {
 515         return sm_ll_mutate(ll, b, set_ref_count, &ref_count, ev);
 516 }
 517
 518 static int inc_ref_count(void *context, uint32_t old, uint32_t *new)
 519 {
 520         *new = old + 1;
 521         return 0;
 522 }
 523
 524 int sm_ll_inc(struct ll_disk *ll, dm_block_t b, enum allocation_event *ev)
 525 {
 526         return sm_ll_mutate(ll, b, inc_ref_count, NULL, ev);
 527 }
 528
 529 static int dec_ref_count(void *context, uint32_t old, uint32_t *new)
 530 {
 531         if (!old) {
 532                 DMERR_LIMIT("unable to decrement a reference count below 0");
 533                 return -EINVAL;
 534         }
 535
 536         *new = old - 1;
 537         return 0;
 538 }
 539
 540 int sm_ll_dec(struct ll_disk *ll, dm_block_t b, enum allocation_event *ev)
 541 {
 542         return sm_ll_mutate(ll, b, dec_ref_count, NULL, ev);
 543 }
 544
 545 int sm_ll_commit(struct ll_disk *ll)
 546 {
 547         int r = 0;
 548
 549         if (ll->bitmap_index_changed) {
 550                 r = ll->commit(ll);
 551                 if (!r)
 552                         ll->bitmap_index_changed = false;
 553         }
 554
 555         return r;
 556 }
 557
 558 /*----------------------------------------------------------------*/
 559
 560 static int metadata_ll_load_ie(struct ll_disk *ll, dm_block_t index,
 561                                struct disk_index_entry *ie)
 562 {
 563         memcpy(ie, ll->mi_le.index + index, sizeof(*ie));
 564         return 0;
 565 }
 566
 567 static int metadata_ll_save_ie(struct ll_disk *ll, dm_block_t index,
 568                                struct disk_index_entry *ie)
 569 {
 570         ll->bitmap_index_changed = true;
 571         memcpy(ll->mi_le.index + index, ie, sizeof(*ie));
 572         return 0;
 573 }
 574
 575 static int metadata_ll_init_index(struct ll_disk *ll)
 576 {
 577         int r;
 578         struct dm_block *b;
 579
 580         r = dm_tm_new_block(ll->tm, &index_validator, &b);
 581         if (r < 0)
 582                 return r;
 583
 584         memcpy(dm_block_data(b), &ll->mi_le, sizeof(ll->mi_le));
 585         ll->bitmap_root = dm_block_location(b);
 586
 587         dm_tm_unlock(ll->tm, b);
 588
 589         return 0;
 590 }
 591
 592 static int metadata_ll_open(struct ll_disk *ll)
 593 {
 594         int r;
 595         struct dm_block *block;
 596
 597         r = dm_tm_read_lock(ll->tm, ll->bitmap_root,
 598                             &index_validator, &block);
 599         if (r)
 600                 return r;
 601
 602         memcpy(&ll->mi_le, dm_block_data(block), sizeof(ll->mi_le));
 603         dm_tm_unlock(ll->tm, block);
 604
 605         return 0;
 606 }
 607
 608 static dm_block_t metadata_ll_max_entries(struct ll_disk *ll)
 609 {
 610         return MAX_METADATA_BITMAPS;
 611 }
 612
 613 static int metadata_ll_commit(struct ll_disk *ll)
 614 {
 615         int r, inc;
 616         struct dm_block *b;
 617
 618         r = dm_tm_shadow_block(ll->tm, ll->bitmap_root, &index_validator, &b, &inc);
 619         if (r)
 620                 return r;
 621
 622         memcpy(dm_block_data(b), &ll->mi_le, sizeof(ll->mi_le));
 623         ll->bitmap_root = dm_block_location(b);
 624
 625         dm_tm_unlock(ll->tm, b);
 626
 627         return 0;
 628 }
 629
 630 int sm_ll_new_metadata(struct ll_disk *ll, struct dm_transaction_manager *tm)
 631 {
 632         int r;
 633
 634         r = sm_ll_init(ll, tm);
 635         if (r < 0)
 636                 return r;
 637
 638         ll->load_ie = metadata_ll_load_ie;
 639         ll->save_ie = metadata_ll_save_ie;
 640         ll->init_index = metadata_ll_init_index;
 641         ll->open_index = metadata_ll_open;
 642         ll->max_entries = metadata_ll_max_entries;
 643         ll->commit = metadata_ll_commit;
 644
 645         ll->nr_blocks = 0;
 646         ll->nr_allocated = 0;
 647
 648         r = ll->init_index(ll);
 649         if (r < 0)
 650                 return r;
 651
 652         r = dm_btree_empty(&ll->ref_count_info, &ll->ref_count_root);
 653         if (r < 0)
 654                 return r;
 655
 656         return 0;
 657 }
 658
 659 int sm_ll_open_metadata(struct ll_disk *ll, struct dm_transaction_manager *tm,
 660                         void *root_le, size_t len)
 661 {
 662         int r;
 663         struct disk_sm_root *smr = root_le;
 664
 665         if (len < sizeof(struct disk_sm_root)) {
 666                 DMERR("sm_metadata root too small");
 667                 return -ENOMEM;
 668         }
 669
 670         r = sm_ll_init(ll, tm);
 671         if (r < 0)
 672                 return r;
 673
 674         ll->load_ie = metadata_ll_load_ie;
 675         ll->save_ie = metadata_ll_save_ie;
 676         ll->init_index = metadata_ll_init_index;
 677         ll->open_index = metadata_ll_open;
 678         ll->max_entries = metadata_ll_max_entries;
 679         ll->commit = metadata_ll_commit;
 680
 681         ll->nr_blocks = le64_to_cpu(smr->nr_blocks);
 682         ll->nr_allocated = le64_to_cpu(smr->nr_allocated);
 683         ll->bitmap_root = le64_to_cpu(smr->bitmap_root);
 684         ll->ref_count_root = le64_to_cpu(smr->ref_count_root);
 685
 686         return ll->open_index(ll);
 687 }
 688
 689 /*----------------------------------------------------------------*/
 690
 691 static int disk_ll_load_ie(struct ll_disk *ll, dm_block_t index,
 692                            struct disk_index_entry *ie)
 693 {
 694         return dm_btree_lookup(&ll->bitmap_info, ll->bitmap_root, &index, ie);
 695 }
 696
 697 static int disk_ll_save_ie(struct ll_disk *ll, dm_block_t index,
 698                            struct disk_index_entry *ie)
 699 {
 700         __dm_bless_for_disk(ie);
 701         return dm_btree_insert(&ll->bitmap_info, ll->bitmap_root,
 702                                &index, ie, &ll->bitmap_root);
 703 }
 704
 705 static int disk_ll_init_index(struct ll_disk *ll)
 706 {
 707         return dm_btree_empty(&ll->bitmap_info, &ll->bitmap_root);
 708 }
 709
 710 static int disk_ll_open(struct ll_disk *ll)
 711 {
 712         /* nothing to do */
 713         return 0;
 714 }
 715
 716 static dm_block_t disk_ll_max_entries(struct ll_disk *ll)
 717 {
 718         return -1ULL;
 719 }
 720
 721 static int disk_ll_commit(struct ll_disk *ll)
 722 {
 723         return 0;
 724 }
 725
 726 int sm_ll_new_disk(struct ll_disk *ll, struct dm_transaction_manager *tm)
 727 {
 728         int r;
 729
 730         r = sm_ll_init(ll, tm);
 731         if (r < 0)
 732                 return r;
 733
 734         ll->load_ie = disk_ll_load_ie;
 735         ll->save_ie = disk_ll_save_ie;
 736         ll->init_index = disk_ll_init_index;
 737         ll->open_index = disk_ll_open;
 738         ll->max_entries = disk_ll_max_entries;
 739         ll->commit = disk_ll_commit;
 740
 741         ll->nr_blocks = 0;
 742         ll->nr_allocated = 0;
 743
 744         r = ll->init_index(ll);
 745         if (r < 0)
 746                 return r;
 747
 748         r = dm_btree_empty(&ll->ref_count_info, &ll->ref_count_root);
 749         if (r < 0)
 750                 return r;
 751
 752         return 0;
 753 }
 754
 755 int sm_ll_open_disk(struct ll_disk *ll, struct dm_transaction_manager *tm,
 756                     void *root_le, size_t len)
 757 {
 758         int r;
 759         struct disk_sm_root *smr = root_le;
 760
 761         if (len < sizeof(struct disk_sm_root)) {
 762                 DMERR("sm_metadata root too small");
 763                 return -ENOMEM;
 764         }
 765
 766         r = sm_ll_init(ll, tm);
 767         if (r < 0)
 768                 return r;
 769
 770         ll->load_ie = disk_ll_load_ie;
 771         ll->save_ie = disk_ll_save_ie;
 772         ll->init_index = disk_ll_init_index;
 773         ll->open_index = disk_ll_open;
 774         ll->max_entries = disk_ll_max_entries;
 775         ll->commit = disk_ll_commit;
 776
 777         ll->nr_blocks = le64_to_cpu(smr->nr_blocks);
 778         ll->nr_allocated = le64_to_cpu(smr->nr_allocated);
 779         ll->bitmap_root = le64_to_cpu(smr->bitmap_root);
 780         ll->ref_count_root = le64_to_cpu(smr->ref_count_root);
 781
 782         return ll->open_index(ll);
 783 }
 784
 785 /*----------------------------------------------------------------*/