src/ext4_balloc.c

   1 /*
   2  * Copyright (c) 2013 Grzegorz Kostka (kostka.grzegorz@gmail.com)
   3  *
   4  * HelenOS:
   5  * Copyright (c) 2012 Martin Sucha
   6  * Copyright (c) 2012 Frantisek Princ
   7  * All rights reserved.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  *
  13  * - Redistributions of source code must retain the above copyright
  14  *   notice, this list of conditions and the following disclaimer.
  15  * - Redistributions in binary form must reproduce the above copyright
  16  *   notice, this list of conditions and the following disclaimer in the
  17  *   documentation and/or other materials provided with the distribution.
  18  * - The name of the author may not be used to endorse or promote products
  19  *   derived from this software without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  26  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  30  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  31  */
  32
  33 /** @addtogroup lwext4
  34  * @{
  35  */
  36 /**
  37  * @file  ext4_balloc.c
  38  * @brief Physical block allocator.
  39  */
  40
  41 #include <ext4_config.h>
  42 #include <ext4_types.h>
  43 #include <ext4_misc.h>
  44 #include <ext4_errno.h>
  45 #include <ext4_debug.h>
  46
  47 #include <ext4_trans.h>
  48 #include <ext4_balloc.h>
  49 #include <ext4_super.h>
  50 #include <ext4_crc32.h>
  51 #include <ext4_block_group.h>
  52 #include <ext4_fs.h>
  53 #include <ext4_bitmap.h>
  54 #include <ext4_inode.h>
  55
  56 /**@brief Compute number of block group from block address.
  57  * @param sb superblock pointer.
  58  * @param baddr Absolute address of block.
  59  * @return Block group index
  60  */
  61 uint32_t ext4_balloc_get_bgid_of_block(struct ext4_sblock *s,
  62                                        uint64_t baddr)
  63 {
  64         if (ext4_get32(s, first_data_block) && baddr)
  65                 baddr--;
  66
  67         return (uint32_t)(baddr / ext4_get32(s, blocks_per_group));
  68 }
  69
  70 /**@brief Compute the starting block address of a block group
  71  * @param sb   superblock pointer.
  72  * @param bgid block group index
  73  * @return Block address
  74  */
  75 uint64_t ext4_balloc_get_block_of_bgid(struct ext4_sblock *s,
  76                                        uint32_t bgid)
  77 {
  78         uint64_t baddr = 0;
  79         if (ext4_get32(s, first_data_block))
  80                 baddr++;
  81
  82         baddr += bgid * ext4_get32(s, blocks_per_group);
  83         return baddr;
  84 }
  85
  86 #if CONFIG_META_CSUM_ENABLE
  87 static uint32_t ext4_balloc_bitmap_csum(struct ext4_sblock *sb,
  88                                         void *bitmap)
  89 {
  90         uint32_t checksum = 0;
  91         if (ext4_sb_feature_ro_com(sb, EXT4_FRO_COM_METADATA_CSUM)) {
  92                 uint32_t blocks_per_group = ext4_get32(sb, blocks_per_group);
  93
  94                 /* First calculate crc32 checksum against fs uuid */
  95                 checksum = ext4_crc32c(EXT4_CRC32_INIT, sb->uuid,
  96                                 sizeof(sb->uuid));
  97                 /* Then calculate crc32 checksum against block_group_desc */
  98                 checksum = ext4_crc32c(checksum, bitmap, blocks_per_group / 8);
  99         }
 100         return checksum;
 101 }
 102 #else
 103 #define ext4_balloc_bitmap_csum(...) 0
 104 #endif
 105
 106 void ext4_balloc_set_bitmap_csum(struct ext4_sblock *sb,
 107                                  struct ext4_bgroup *bg,
 108                                  void *bitmap __unused)
 109 {
 110         int desc_size = ext4_sb_get_desc_size(sb);
 111         uint32_t checksum = ext4_balloc_bitmap_csum(sb, bitmap);
 112         uint16_t lo_checksum = to_le16(checksum & 0xFFFF),
 113                  hi_checksum = to_le16(checksum >> 16);
 114
 115         if (!ext4_sb_feature_ro_com(sb, EXT4_FRO_COM_METADATA_CSUM))
 116                 return;
 117
 118         /* See if we need to assign a 32bit checksum */
 119         bg->block_bitmap_csum_lo = lo_checksum;
 120         if (desc_size == EXT4_MAX_BLOCK_GROUP_DESCRIPTOR_SIZE)
 121                 bg->block_bitmap_csum_hi = hi_checksum;
 122
 123 }
 124
 125 #if CONFIG_META_CSUM_ENABLE
 126 static bool
 127 ext4_balloc_verify_bitmap_csum(struct ext4_sblock *sb,
 128                                struct ext4_bgroup *bg,
 129                                void *bitmap __unused)
 130 {
 131         int desc_size = ext4_sb_get_desc_size(sb);
 132         uint32_t checksum = ext4_balloc_bitmap_csum(sb, bitmap);
 133         uint16_t lo_checksum = to_le16(checksum & 0xFFFF),
 134                  hi_checksum = to_le16(checksum >> 16);
 135
 136         if (!ext4_sb_feature_ro_com(sb, EXT4_FRO_COM_METADATA_CSUM))
 137                 return true;
 138
 139         if (bg->block_bitmap_csum_lo != lo_checksum)
 140                 return false;
 141
 142         if (desc_size == EXT4_MAX_BLOCK_GROUP_DESCRIPTOR_SIZE)
 143                 if (bg->block_bitmap_csum_hi != hi_checksum)
 144                         return false;
 145
 146         return true;
 147 }
 148 #else
 149 #define ext4_balloc_verify_bitmap_csum(...) true
 150 #endif
 151
 152 int ext4_balloc_free_block(struct ext4_inode_ref *inode_ref, ext4_fsblk_t baddr)
 153 {
 154         struct ext4_fs *fs = inode_ref->fs;
 155         struct ext4_sblock *sb = &fs->sb;
 156
 157         uint32_t bg_id = ext4_balloc_get_bgid_of_block(sb, baddr);
 158         uint32_t index_in_group = ext4_fs_addr_to_idx_bg(sb, baddr);
 159
 160         /* Load block group reference */
 161         struct ext4_block_group_ref bg_ref;
 162         int rc = ext4_fs_get_block_group_ref(fs, bg_id, &bg_ref);
 163         if (rc != EOK)
 164                 return rc;
 165
 166         struct ext4_bgroup *bg = bg_ref.block_group;
 167
 168         /* Load block with bitmap */
 169         ext4_fsblk_t bitmap_block_addr =
 170             ext4_bg_get_block_bitmap(bg, sb);
 171
 172         struct ext4_block bitmap_block;
 173
 174         rc = ext4_trans_block_get(fs->bdev, &bitmap_block, bitmap_block_addr);
 175         if (rc != EOK) {
 176                 ext4_fs_put_block_group_ref(&bg_ref);
 177                 return rc;
 178         }
 179
 180         if (!ext4_balloc_verify_bitmap_csum(sb, bg, bitmap_block.data)) {
 181                 ext4_dbg(DEBUG_BALLOC,
 182                         DBG_WARN "Bitmap checksum failed."
 183                         "Group: %" PRIu32"\n",
 184                         bg_ref.index);
 185         }
 186
 187         /* Modify bitmap */
 188         ext4_bmap_bit_clr(bitmap_block.data, index_in_group);
 189         ext4_balloc_set_bitmap_csum(sb, bg, bitmap_block.data);
 190         ext4_trans_set_block_dirty(bitmap_block.buf);
 191
 192         /* Release block with bitmap */
 193         rc = ext4_block_set(fs->bdev, &bitmap_block);
 194         if (rc != EOK) {
 195                 /* Error in saving bitmap */
 196                 ext4_fs_put_block_group_ref(&bg_ref);
 197                 return rc;
 198         }
 199
 200         uint32_t block_size = ext4_sb_get_block_size(sb);
 201
 202         /* Update superblock free blocks count */
 203         uint64_t sb_free_blocks = ext4_sb_get_free_blocks_cnt(sb);
 204         sb_free_blocks++;
 205         ext4_sb_set_free_blocks_cnt(sb, sb_free_blocks);
 206
 207         /* Update inode blocks count */
 208         uint64_t ino_blocks = ext4_inode_get_blocks_count(sb, inode_ref->inode);
 209         ino_blocks -= block_size / EXT4_INODE_BLOCK_SIZE;
 210         ext4_inode_set_blocks_count(sb, inode_ref->inode, ino_blocks);
 211         inode_ref->dirty = true;
 212
 213         /* Update block group free blocks count */
 214         uint32_t free_blocks = ext4_bg_get_free_blocks_count(bg, sb);
 215         free_blocks++;
 216         ext4_bg_set_free_blocks_count(bg, sb, free_blocks);
 217
 218         bg_ref.dirty = true;
 219
 220         rc = ext4_trans_try_revoke_block(fs->bdev, baddr);
 221         if (rc != EOK) {
 222                 bg_ref.dirty = false;
 223                 ext4_fs_put_block_group_ref(&bg_ref);
 224                 return rc;
 225         }
 226         ext4_bcache_invalidate_lba(fs->bdev->bc, baddr, 1);
 227         /* Release block group reference */
 228         rc = ext4_fs_put_block_group_ref(&bg_ref);
 229
 230         return rc;
 231 }
 232
 233 int ext4_balloc_free_blocks(struct ext4_inode_ref *inode_ref,
 234                             ext4_fsblk_t first, uint32_t count)
 235 {
 236         int rc = EOK;
 237         uint32_t blk_cnt = count;
 238         ext4_fsblk_t start_block = first;
 239         struct ext4_fs *fs = inode_ref->fs;
 240         struct ext4_sblock *sb = &fs->sb;
 241
 242         /* Compute indexes */
 243         uint32_t bg_first = ext4_balloc_get_bgid_of_block(sb, first);
 244
 245         /* Compute indexes */
 246         uint32_t bg_last = ext4_balloc_get_bgid_of_block(sb, first + count - 1);
 247
 248         if (!ext4_sb_feature_incom(sb, EXT4_FINCOM_FLEX_BG)) {
 249                 /*It is not possible without flex_bg that blocks are continuous
 250                  * and and last block belongs to other bg.*/
 251                 if (bg_last != bg_first) {
 252                         ext4_dbg(DEBUG_BALLOC, DBG_WARN "FLEX_BG: disabled & "
 253                                 "bg_last: %"PRIu32" bg_first: %"PRIu32"\n",
 254                                 bg_last, bg_first);
 255                 }
 256         }
 257
 258         /* Load block group reference */
 259         struct ext4_block_group_ref bg_ref;
 260         while (bg_first <= bg_last) {
 261
 262                 rc = ext4_fs_get_block_group_ref(fs, bg_first, &bg_ref);
 263                 if (rc != EOK)
 264                         return rc;
 265
 266                 struct ext4_bgroup *bg = bg_ref.block_group;
 267
 268                 uint32_t idx_in_bg_first;
 269                 idx_in_bg_first = ext4_fs_addr_to_idx_bg(sb, first);
 270
 271                 /* Load block with bitmap */
 272                 ext4_fsblk_t bitmap_blk = ext4_bg_get_block_bitmap(bg, sb);
 273
 274                 struct ext4_block blk;
 275                 rc = ext4_trans_block_get(fs->bdev, &blk, bitmap_blk);
 276                 if (rc != EOK) {
 277                         ext4_fs_put_block_group_ref(&bg_ref);
 278                         return rc;
 279                 }
 280
 281                 if (!ext4_balloc_verify_bitmap_csum(sb, bg, blk.data)) {
 282                         ext4_dbg(DEBUG_BALLOC,
 283                                 DBG_WARN "Bitmap checksum failed."
 284                                 "Group: %" PRIu32"\n",
 285                                 bg_ref.index);
 286                 }
 287                 uint32_t free_cnt;
 288                 free_cnt = ext4_sb_get_block_size(sb) * 8 - idx_in_bg_first;
 289
 290                 /*If last block, free only count blocks*/
 291                 free_cnt = count > free_cnt ? free_cnt : count;
 292
 293                 /* Modify bitmap */
 294                 ext4_bmap_bits_free(blk.data, idx_in_bg_first, free_cnt);
 295                 ext4_balloc_set_bitmap_csum(sb, bg, blk.data);
 296                 ext4_trans_set_block_dirty(blk.buf);
 297
 298                 count -= free_cnt;
 299                 first += free_cnt;
 300
 301                 /* Release block with bitmap */
 302                 rc = ext4_block_set(fs->bdev, &blk);
 303                 if (rc != EOK) {
 304                         ext4_fs_put_block_group_ref(&bg_ref);
 305                         return rc;
 306                 }
 307
 308                 uint32_t block_size = ext4_sb_get_block_size(sb);
 309
 310                 /* Update superblock free blocks count */
 311                 uint64_t sb_free_blocks = ext4_sb_get_free_blocks_cnt(sb);
 312                 sb_free_blocks += free_cnt;
 313                 ext4_sb_set_free_blocks_cnt(sb, sb_free_blocks);
 314
 315                 /* Update inode blocks count */
 316                 uint64_t ino_blocks;
 317                 ino_blocks = ext4_inode_get_blocks_count(sb, inode_ref->inode);
 318                 ino_blocks -= free_cnt * (block_size / EXT4_INODE_BLOCK_SIZE);
 319                 ext4_inode_set_blocks_count(sb, inode_ref->inode, ino_blocks);
 320                 inode_ref->dirty = true;
 321
 322                 /* Update block group free blocks count */
 323                 uint32_t free_blocks;
 324                 free_blocks = ext4_bg_get_free_blocks_count(bg, sb);
 325                 free_blocks += free_cnt;
 326                 ext4_bg_set_free_blocks_count(bg, sb, free_blocks);
 327                 bg_ref.dirty = true;
 328
 329                 /* Release block group reference */
 330                 rc = ext4_fs_put_block_group_ref(&bg_ref);
 331                 if (rc != EOK)
 332                         break;
 333
 334                 bg_first++;
 335         }
 336
 337         uint32_t i;
 338         for (i = 0;i < blk_cnt;i++) {
 339                 rc = ext4_trans_try_revoke_block(fs->bdev, start_block + i);
 340                 if (rc != EOK)
 341                         return rc;
 342
 343         }
 344
 345         ext4_bcache_invalidate_lba(fs->bdev->bc, start_block, blk_cnt);
 346         /*All blocks should be released*/
 347         ext4_assert(count == 0);
 348
 349         return rc;
 350 }
 351
 352 int ext4_balloc_alloc_block(struct ext4_inode_ref *inode_ref,
 353                             ext4_fsblk_t goal,
 354                             ext4_fsblk_t *fblock)
 355 {
 356         ext4_fsblk_t alloc = 0;
 357         ext4_fsblk_t bmp_blk_adr;
 358         uint32_t rel_blk_idx = 0;
 359         uint64_t free_blocks;
 360         int r;
 361         struct ext4_sblock *sb = &inode_ref->fs->sb;
 362
 363         /* Load block group number for goal and relative index */
 364         uint32_t bg_id = ext4_balloc_get_bgid_of_block(sb, goal);
 365         uint32_t idx_in_bg = ext4_fs_addr_to_idx_bg(sb, goal);
 366
 367         struct ext4_block b;
 368         struct ext4_block_group_ref bg_ref;
 369
 370         /* Load block group reference */
 371         r = ext4_fs_get_block_group_ref(inode_ref->fs, bg_id, &bg_ref);
 372         if (r != EOK)
 373                 return r;
 374
 375         struct ext4_bgroup *bg = bg_ref.block_group;
 376
 377         free_blocks = ext4_bg_get_free_blocks_count(bg_ref.block_group, sb);
 378         if (free_blocks == 0) {
 379                 /* This group has no free blocks */
 380                 goto goal_failed;
 381         }
 382
 383         /* Compute indexes */
 384         ext4_fsblk_t first_in_bg;
 385         first_in_bg = ext4_balloc_get_block_of_bgid(sb, bg_ref.index);
 386
 387         uint32_t first_in_bg_index;
 388         first_in_bg_index = ext4_fs_addr_to_idx_bg(sb, first_in_bg);
 389
 390         if (idx_in_bg < first_in_bg_index)
 391                 idx_in_bg = first_in_bg_index;
 392
 393         /* Load block with bitmap */
 394         bmp_blk_adr = ext4_bg_get_block_bitmap(bg_ref.block_group, sb);
 395
 396         r = ext4_trans_block_get(inode_ref->fs->bdev, &b, bmp_blk_adr);
 397         if (r != EOK) {
 398                 ext4_fs_put_block_group_ref(&bg_ref);
 399                 return r;
 400         }
 401
 402         if (!ext4_balloc_verify_bitmap_csum(sb, bg, b.data)) {
 403                 ext4_dbg(DEBUG_BALLOC,
 404                         DBG_WARN "Bitmap checksum failed."
 405                         "Group: %" PRIu32"\n",
 406                         bg_ref.index);
 407         }
 408
 409         /* Check if goal is free */
 410         if (ext4_bmap_is_bit_clr(b.data, idx_in_bg)) {
 411                 ext4_bmap_bit_set(b.data, idx_in_bg);
 412                 ext4_balloc_set_bitmap_csum(sb, bg_ref.block_group,
 413                                             b.data);
 414                 ext4_trans_set_block_dirty(b.buf);
 415                 r = ext4_block_set(inode_ref->fs->bdev, &b);
 416                 if (r != EOK) {
 417                         ext4_fs_put_block_group_ref(&bg_ref);
 418                         return r;
 419                 }
 420
 421                 alloc = ext4_fs_bg_idx_to_addr(sb, idx_in_bg, bg_id);
 422                 goto success;
 423         }
 424
 425         uint32_t blk_in_bg = ext4_blocks_in_group_cnt(sb, bg_id);
 426
 427         uint32_t end_idx = (idx_in_bg + 63) & ~63;
 428         if (end_idx > blk_in_bg)
 429                 end_idx = blk_in_bg;
 430
 431         /* Try to find free block near to goal */
 432         uint32_t tmp_idx;
 433         for (tmp_idx = idx_in_bg + 1; tmp_idx < end_idx; ++tmp_idx) {
 434                 if (ext4_bmap_is_bit_clr(b.data, tmp_idx)) {
 435                         ext4_bmap_bit_set(b.data, tmp_idx);
 436
 437                         ext4_balloc_set_bitmap_csum(sb, bg, b.data);
 438                         ext4_trans_set_block_dirty(b.buf);
 439                         r = ext4_block_set(inode_ref->fs->bdev, &b);
 440                         if (r != EOK)
 441                                 return r;
 442
 443                         alloc = ext4_fs_bg_idx_to_addr(sb, tmp_idx, bg_id);
 444                         goto success;
 445                 }
 446         }
 447
 448         /* Find free bit in bitmap */
 449         r = ext4_bmap_bit_find_clr(b.data, idx_in_bg, blk_in_bg, &rel_blk_idx);
 450         if (r == EOK) {
 451                 ext4_bmap_bit_set(b.data, rel_blk_idx);
 452                 ext4_balloc_set_bitmap_csum(sb, bg_ref.block_group, b.data);
 453                 ext4_trans_set_block_dirty(b.buf);
 454                 r = ext4_block_set(inode_ref->fs->bdev, &b);
 455                 if (r != EOK)
 456                         return r;
 457
 458                 alloc = ext4_fs_bg_idx_to_addr(sb, rel_blk_idx, bg_id);
 459                 goto success;
 460         }
 461
 462         /* No free block found yet */
 463         r = ext4_block_set(inode_ref->fs->bdev, &b);
 464         if (r != EOK) {
 465                 ext4_fs_put_block_group_ref(&bg_ref);
 466                 return r;
 467         }
 468
 469 goal_failed:
 470
 471         r = ext4_fs_put_block_group_ref(&bg_ref);
 472         if (r != EOK)
 473                 return r;
 474
 475         /* Try other block groups */
 476         uint32_t block_group_count = ext4_block_group_cnt(sb);
 477         uint32_t bgid = (bg_id + 1) % block_group_count;
 478         uint32_t count = block_group_count;
 479
 480         while (count > 0) {
 481                 r = ext4_fs_get_block_group_ref(inode_ref->fs, bgid, &bg_ref);
 482                 if (r != EOK)
 483                         return r;
 484
 485                 struct ext4_bgroup *bg = bg_ref.block_group;
 486                 free_blocks = ext4_bg_get_free_blocks_count(bg, sb);
 487                 if (free_blocks == 0) {
 488                         /* This group has no free blocks */
 489                         goto next_group;
 490                 }
 491
 492                 /* Load block with bitmap */
 493                 bmp_blk_adr = ext4_bg_get_block_bitmap(bg, sb);
 494                 r = ext4_trans_block_get(inode_ref->fs->bdev, &b, bmp_blk_adr);
 495                 if (r != EOK) {
 496                         ext4_fs_put_block_group_ref(&bg_ref);
 497                         return r;
 498                 }
 499
 500                 if (!ext4_balloc_verify_bitmap_csum(sb, bg, b.data)) {
 501                         ext4_dbg(DEBUG_BALLOC,
 502                                 DBG_WARN "Bitmap checksum failed."
 503                                 "Group: %" PRIu32"\n",
 504                                 bg_ref.index);
 505                 }
 506
 507                 /* Compute indexes */
 508                 first_in_bg = ext4_balloc_get_block_of_bgid(sb, bgid);
 509                 idx_in_bg = ext4_fs_addr_to_idx_bg(sb, first_in_bg);
 510                 blk_in_bg = ext4_blocks_in_group_cnt(sb, bgid);
 511                 first_in_bg_index = ext4_fs_addr_to_idx_bg(sb, first_in_bg);
 512
 513                 if (idx_in_bg < first_in_bg_index)
 514                         idx_in_bg = first_in_bg_index;
 515
 516                 r = ext4_bmap_bit_find_clr(b.data, idx_in_bg, blk_in_bg,
 517                                 &rel_blk_idx);
 518                 if (r == EOK) {
 519                         ext4_bmap_bit_set(b.data, rel_blk_idx);
 520                         ext4_balloc_set_bitmap_csum(sb, bg, b.data);
 521                         ext4_trans_set_block_dirty(b.buf);
 522                         r = ext4_block_set(inode_ref->fs->bdev, &b);
 523                         if (r != EOK) {
 524                                 ext4_fs_put_block_group_ref(&bg_ref);
 525                                 return r;
 526                         }
 527
 528                         alloc = ext4_fs_bg_idx_to_addr(sb, rel_blk_idx, bgid);
 529                         goto success;
 530                 }
 531
 532                 r = ext4_block_set(inode_ref->fs->bdev, &b);
 533                 if (r != EOK) {
 534                         ext4_fs_put_block_group_ref(&bg_ref);
 535                         return r;
 536                 }
 537
 538         next_group:
 539                 r = ext4_fs_put_block_group_ref(&bg_ref);
 540                 if (r != EOK) {
 541                         return r;
 542                 }
 543
 544                 /* Goto next group */
 545                 bgid = (bgid + 1) % block_group_count;
 546                 count--;
 547         }
 548
 549         return ENOSPC;
 550
 551 success:
 552     /* Empty command - because of syntax */
 553     ;
 554
 555         uint32_t block_size = ext4_sb_get_block_size(sb);
 556
 557         /* Update superblock free blocks count */
 558         uint64_t sb_free_blocks = ext4_sb_get_free_blocks_cnt(sb);
 559         sb_free_blocks--;
 560         ext4_sb_set_free_blocks_cnt(sb, sb_free_blocks);
 561
 562         /* Update inode blocks (different block size!) count */
 563         uint64_t ino_blocks = ext4_inode_get_blocks_count(sb, inode_ref->inode);
 564         ino_blocks += block_size / EXT4_INODE_BLOCK_SIZE;
 565         ext4_inode_set_blocks_count(sb, inode_ref->inode, ino_blocks);
 566         inode_ref->dirty = true;
 567
 568         /* Update block group free blocks count */
 569
 570         uint32_t fb_cnt = ext4_bg_get_free_blocks_count(bg_ref.block_group, sb);
 571         fb_cnt--;
 572         ext4_bg_set_free_blocks_count(bg_ref.block_group, sb, fb_cnt);
 573
 574         bg_ref.dirty = true;
 575         r = ext4_fs_put_block_group_ref(&bg_ref);
 576
 577         *fblock = alloc;
 578         return r;
 579 }
 580
 581 int ext4_balloc_try_alloc_block(struct ext4_inode_ref *inode_ref,
 582                                 ext4_fsblk_t baddr, bool *free)
 583 {
 584         int rc;
 585
 586         struct ext4_fs *fs = inode_ref->fs;
 587         struct ext4_sblock *sb = &fs->sb;
 588
 589         /* Compute indexes */
 590         uint32_t block_group = ext4_balloc_get_bgid_of_block(sb, baddr);
 591         uint32_t index_in_group = ext4_fs_addr_to_idx_bg(sb, baddr);
 592
 593         /* Load block group reference */
 594         struct ext4_block_group_ref bg_ref;
 595         rc = ext4_fs_get_block_group_ref(fs, block_group, &bg_ref);
 596         if (rc != EOK)
 597                 return rc;
 598
 599         /* Load block with bitmap */
 600         ext4_fsblk_t bmp_blk_addr;
 601         bmp_blk_addr = ext4_bg_get_block_bitmap(bg_ref.block_group, sb);
 602
 603         struct ext4_block b;
 604         rc = ext4_trans_block_get(fs->bdev, &b, bmp_blk_addr);
 605         if (rc != EOK) {
 606                 ext4_fs_put_block_group_ref(&bg_ref);
 607                 return rc;
 608         }
 609
 610         if (!ext4_balloc_verify_bitmap_csum(sb, bg_ref.block_group, b.data)) {
 611                 ext4_dbg(DEBUG_BALLOC,
 612                         DBG_WARN "Bitmap checksum failed."
 613                         "Group: %" PRIu32"\n",
 614                         bg_ref.index);
 615         }
 616
 617         /* Check if block is free */
 618         *free = ext4_bmap_is_bit_clr(b.data, index_in_group);
 619
 620         /* Allocate block if possible */
 621         if (*free) {
 622                 ext4_bmap_bit_set(b.data, index_in_group);
 623                 ext4_balloc_set_bitmap_csum(sb, bg_ref.block_group, b.data);
 624                 ext4_trans_set_block_dirty(b.buf);
 625         }
 626
 627         /* Release block with bitmap */
 628         rc = ext4_block_set(fs->bdev, &b);
 629         if (rc != EOK) {
 630                 /* Error in saving bitmap */
 631                 ext4_fs_put_block_group_ref(&bg_ref);
 632                 return rc;
 633         }
 634
 635         /* If block is not free, return */
 636         if (!(*free))
 637                 goto terminate;
 638
 639         uint32_t block_size = ext4_sb_get_block_size(sb);
 640
 641         /* Update superblock free blocks count */
 642         uint64_t sb_free_blocks = ext4_sb_get_free_blocks_cnt(sb);
 643         sb_free_blocks--;
 644         ext4_sb_set_free_blocks_cnt(sb, sb_free_blocks);
 645
 646         /* Update inode blocks count */
 647         uint64_t ino_blocks = ext4_inode_get_blocks_count(sb, inode_ref->inode);
 648         ino_blocks += block_size / EXT4_INODE_BLOCK_SIZE;
 649         ext4_inode_set_blocks_count(sb, inode_ref->inode, ino_blocks);
 650         inode_ref->dirty = true;
 651
 652         /* Update block group free blocks count */
 653         uint32_t fb_cnt = ext4_bg_get_free_blocks_count(bg_ref.block_group, sb);
 654         fb_cnt--;
 655         ext4_bg_set_free_blocks_count(bg_ref.block_group, sb, fb_cnt);
 656
 657         bg_ref.dirty = true;
 658
 659 terminate:
 660         return ext4_fs_put_block_group_ref(&bg_ref);
 661 }
 662
 663 /**
 664  * @}
 665  */