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         return ext4_fs_put_block_group_ref(&bg_ref);
 229 }
 230
 231 int ext4_balloc_free_blocks(struct ext4_inode_ref *inode_ref,
 232                             ext4_fsblk_t first, uint32_t count)
 233 {
 234         int rc = EOK;
 235         struct ext4_fs *fs = inode_ref->fs;
 236         struct ext4_sblock *sb = &fs->sb;
 237
 238         /* Compute indexes */
 239         uint32_t bg_first = ext4_balloc_get_bgid_of_block(sb, first);
 240
 241         /* Compute indexes */
 242         uint32_t bg_last = ext4_balloc_get_bgid_of_block(sb, first + count - 1);
 243
 244         if (!ext4_sb_feature_incom(sb, EXT4_FINCOM_FLEX_BG)) {
 245                 /*It is not possible without flex_bg that blocks are continuous
 246                  * and and last block belongs to other bg.*/
 247                 if (bg_last != bg_first) {
 248                         ext4_dbg(DEBUG_BALLOC, DBG_WARN "FLEX_BG: disabled & "
 249                                 "bg_last: %"PRIu32" bg_first: %"PRIu32"\n",
 250                                 bg_last, bg_first);
 251                 }
 252         }
 253
 254         /* Load block group reference */
 255         struct ext4_block_group_ref bg_ref;
 256         while (bg_first <= bg_last) {
 257
 258                 rc = ext4_fs_get_block_group_ref(fs, bg_first, &bg_ref);
 259                 if (rc != EOK)
 260                         return rc;
 261
 262                 struct ext4_bgroup *bg = bg_ref.block_group;
 263
 264                 uint32_t idx_in_bg_first;
 265                 idx_in_bg_first = ext4_fs_addr_to_idx_bg(sb, first);
 266
 267                 /* Load block with bitmap */
 268                 ext4_fsblk_t bitmap_blk = ext4_bg_get_block_bitmap(bg, sb);
 269
 270                 struct ext4_block blk;
 271                 rc = ext4_trans_block_get(fs->bdev, &blk, bitmap_blk);
 272                 if (rc != EOK) {
 273                         ext4_fs_put_block_group_ref(&bg_ref);
 274                         return rc;
 275                 }
 276
 277                 if (!ext4_balloc_verify_bitmap_csum(sb, bg, blk.data)) {
 278                         ext4_dbg(DEBUG_BALLOC,
 279                                 DBG_WARN "Bitmap checksum failed."
 280                                 "Group: %" PRIu32"\n",
 281                                 bg_ref.index);
 282                 }
 283                 uint32_t free_cnt;
 284                 free_cnt = ext4_sb_get_block_size(sb) * 8 - idx_in_bg_first;
 285
 286                 /*If last block, free only count blocks*/
 287                 free_cnt = count > free_cnt ? free_cnt : count;
 288
 289                 /* Modify bitmap */
 290                 ext4_bmap_bits_free(blk.data, idx_in_bg_first, free_cnt);
 291                 ext4_balloc_set_bitmap_csum(sb, bg, blk.data);
 292                 ext4_trans_set_block_dirty(blk.buf);
 293
 294                 count -= free_cnt;
 295                 first += free_cnt;
 296
 297                 /* Release block with bitmap */
 298                 rc = ext4_block_set(fs->bdev, &blk);
 299                 if (rc != EOK) {
 300                         ext4_fs_put_block_group_ref(&bg_ref);
 301                         return rc;
 302                 }
 303
 304                 uint32_t block_size = ext4_sb_get_block_size(sb);
 305
 306                 /* Update superblock free blocks count */
 307                 uint64_t sb_free_blocks = ext4_sb_get_free_blocks_cnt(sb);
 308                 sb_free_blocks += free_cnt;
 309                 ext4_sb_set_free_blocks_cnt(sb, sb_free_blocks);
 310
 311                 /* Update inode blocks count */
 312                 uint64_t ino_blocks;
 313                 ino_blocks = ext4_inode_get_blocks_count(sb, inode_ref->inode);
 314                 ino_blocks -= free_cnt * (block_size / EXT4_INODE_BLOCK_SIZE);
 315                 ext4_inode_set_blocks_count(sb, inode_ref->inode, ino_blocks);
 316                 inode_ref->dirty = true;
 317
 318                 /* Update block group free blocks count */
 319                 uint32_t free_blocks;
 320                 free_blocks = ext4_bg_get_free_blocks_count(bg, sb);
 321                 free_blocks += free_cnt;
 322                 ext4_bg_set_free_blocks_count(bg, sb, free_blocks);
 323                 bg_ref.dirty = true;
 324
 325                 /* Release block group reference */
 326                 rc = ext4_fs_put_block_group_ref(&bg_ref);
 327                 if (rc != EOK)
 328                         break;
 329
 330                 bg_first++;
 331         }
 332
 333         uint32_t i;
 334         for (i = 0;i < count;i++) {
 335                 rc = ext4_trans_try_revoke_block(fs->bdev, first + i);
 336                 if (rc != EOK)
 337                         return rc;
 338
 339         }
 340
 341         ext4_bcache_invalidate_lba(fs->bdev->bc, first, count);
 342         /*All blocks should be released*/
 343         ext4_assert(count == 0);
 344         return rc;
 345 }
 346
 347 int ext4_balloc_alloc_block(struct ext4_inode_ref *inode_ref,
 348                             ext4_fsblk_t goal,
 349                             ext4_fsblk_t *fblock)
 350 {
 351         ext4_fsblk_t alloc = 0;
 352         ext4_fsblk_t bmp_blk_adr;
 353         uint32_t rel_blk_idx = 0;
 354         uint64_t free_blocks;
 355         int r;
 356         struct ext4_sblock *sb = &inode_ref->fs->sb;
 357
 358         /* Load block group number for goal and relative index */
 359         uint32_t bg_id = ext4_balloc_get_bgid_of_block(sb, goal);
 360         uint32_t idx_in_bg = ext4_fs_addr_to_idx_bg(sb, goal);
 361
 362         struct ext4_block b;
 363         struct ext4_block_group_ref bg_ref;
 364
 365         /* Load block group reference */
 366         r = ext4_fs_get_block_group_ref(inode_ref->fs, bg_id, &bg_ref);
 367         if (r != EOK)
 368                 return r;
 369
 370         struct ext4_bgroup *bg = bg_ref.block_group;
 371
 372         free_blocks = ext4_bg_get_free_blocks_count(bg_ref.block_group, sb);
 373         if (free_blocks == 0) {
 374                 /* This group has no free blocks */
 375                 goto goal_failed;
 376         }
 377
 378         /* Compute indexes */
 379         ext4_fsblk_t first_in_bg;
 380         first_in_bg = ext4_balloc_get_block_of_bgid(sb, bg_ref.index);
 381
 382         uint32_t first_in_bg_index;
 383         first_in_bg_index = ext4_fs_addr_to_idx_bg(sb, first_in_bg);
 384
 385         if (idx_in_bg < first_in_bg_index)
 386                 idx_in_bg = first_in_bg_index;
 387
 388         /* Load block with bitmap */
 389         bmp_blk_adr = ext4_bg_get_block_bitmap(bg_ref.block_group, sb);
 390
 391         r = ext4_trans_block_get(inode_ref->fs->bdev, &b, bmp_blk_adr);
 392         if (r != EOK) {
 393                 ext4_fs_put_block_group_ref(&bg_ref);
 394                 return r;
 395         }
 396
 397         if (!ext4_balloc_verify_bitmap_csum(sb, bg, b.data)) {
 398                 ext4_dbg(DEBUG_BALLOC,
 399                         DBG_WARN "Bitmap checksum failed."
 400                         "Group: %" PRIu32"\n",
 401                         bg_ref.index);
 402         }
 403
 404         /* Check if goal is free */
 405         if (ext4_bmap_is_bit_clr(b.data, idx_in_bg)) {
 406                 ext4_bmap_bit_set(b.data, idx_in_bg);
 407                 ext4_balloc_set_bitmap_csum(sb, bg_ref.block_group,
 408                                             b.data);
 409                 ext4_trans_set_block_dirty(b.buf);
 410                 r = ext4_block_set(inode_ref->fs->bdev, &b);
 411                 if (r != EOK) {
 412                         ext4_fs_put_block_group_ref(&bg_ref);
 413                         return r;
 414                 }
 415
 416                 alloc = ext4_fs_bg_idx_to_addr(sb, idx_in_bg, bg_id);
 417                 goto success;
 418         }
 419
 420         uint32_t blk_in_bg = ext4_blocks_in_group_cnt(sb, bg_id);
 421
 422         uint32_t end_idx = (idx_in_bg + 63) & ~63;
 423         if (end_idx > blk_in_bg)
 424                 end_idx = blk_in_bg;
 425
 426         /* Try to find free block near to goal */
 427         uint32_t tmp_idx;
 428         for (tmp_idx = idx_in_bg + 1; tmp_idx < end_idx; ++tmp_idx) {
 429                 if (ext4_bmap_is_bit_clr(b.data, tmp_idx)) {
 430                         ext4_bmap_bit_set(b.data, tmp_idx);
 431
 432                         ext4_balloc_set_bitmap_csum(sb, bg, b.data);
 433                         ext4_trans_set_block_dirty(b.buf);
 434                         r = ext4_block_set(inode_ref->fs->bdev, &b);
 435                         if (r != EOK)
 436                                 return r;
 437
 438                         alloc = ext4_fs_bg_idx_to_addr(sb, tmp_idx, bg_id);
 439                         goto success;
 440                 }
 441         }
 442
 443         /* Find free bit in bitmap */
 444         r = ext4_bmap_bit_find_clr(b.data, idx_in_bg, blk_in_bg, &rel_blk_idx);
 445         if (r == EOK) {
 446                 ext4_bmap_bit_set(b.data, rel_blk_idx);
 447                 ext4_balloc_set_bitmap_csum(sb, bg_ref.block_group, b.data);
 448                 ext4_trans_set_block_dirty(b.buf);
 449                 r = ext4_block_set(inode_ref->fs->bdev, &b);
 450                 if (r != EOK)
 451                         return r;
 452
 453                 alloc = ext4_fs_bg_idx_to_addr(sb, rel_blk_idx, bg_id);
 454                 goto success;
 455         }
 456
 457         /* No free block found yet */
 458         r = ext4_block_set(inode_ref->fs->bdev, &b);
 459         if (r != EOK) {
 460                 ext4_fs_put_block_group_ref(&bg_ref);
 461                 return r;
 462         }
 463
 464 goal_failed:
 465
 466         r = ext4_fs_put_block_group_ref(&bg_ref);
 467         if (r != EOK)
 468                 return r;
 469
 470         /* Try other block groups */
 471         uint32_t block_group_count = ext4_block_group_cnt(sb);
 472         uint32_t bgid = (bg_id + 1) % block_group_count;
 473         uint32_t count = block_group_count;
 474
 475         while (count > 0) {
 476                 r = ext4_fs_get_block_group_ref(inode_ref->fs, bgid, &bg_ref);
 477                 if (r != EOK)
 478                         return r;
 479
 480                 struct ext4_bgroup *bg = bg_ref.block_group;
 481                 free_blocks = ext4_bg_get_free_blocks_count(bg, sb);
 482                 if (free_blocks == 0) {
 483                         /* This group has no free blocks */
 484                         goto next_group;
 485                 }
 486
 487                 /* Load block with bitmap */
 488                 bmp_blk_adr = ext4_bg_get_block_bitmap(bg, sb);
 489                 r = ext4_trans_block_get(inode_ref->fs->bdev, &b, bmp_blk_adr);
 490                 if (r != EOK) {
 491                         ext4_fs_put_block_group_ref(&bg_ref);
 492                         return r;
 493                 }
 494
 495                 if (!ext4_balloc_verify_bitmap_csum(sb, bg, b.data)) {
 496                         ext4_dbg(DEBUG_BALLOC,
 497                                 DBG_WARN "Bitmap checksum failed."
 498                                 "Group: %" PRIu32"\n",
 499                                 bg_ref.index);
 500                 }
 501
 502                 /* Compute indexes */
 503                 first_in_bg = ext4_balloc_get_block_of_bgid(sb, bgid);
 504                 idx_in_bg = ext4_fs_addr_to_idx_bg(sb, first_in_bg);
 505                 blk_in_bg = ext4_blocks_in_group_cnt(sb, bgid);
 506                 first_in_bg_index = ext4_fs_addr_to_idx_bg(sb, first_in_bg);
 507
 508                 if (idx_in_bg < first_in_bg_index)
 509                         idx_in_bg = first_in_bg_index;
 510
 511                 r = ext4_bmap_bit_find_clr(b.data, idx_in_bg, blk_in_bg,
 512                                 &rel_blk_idx);
 513                 if (r == EOK) {
 514                         ext4_bmap_bit_set(b.data, rel_blk_idx);
 515                         ext4_balloc_set_bitmap_csum(sb, bg, b.data);
 516                         ext4_trans_set_block_dirty(b.buf);
 517                         r = ext4_block_set(inode_ref->fs->bdev, &b);
 518                         if (r != EOK) {
 519                                 ext4_fs_put_block_group_ref(&bg_ref);
 520                                 return r;
 521                         }
 522
 523                         alloc = ext4_fs_bg_idx_to_addr(sb, rel_blk_idx, bgid);
 524                         goto success;
 525                 }
 526
 527                 r = ext4_block_set(inode_ref->fs->bdev, &b);
 528                 if (r != EOK) {
 529                         ext4_fs_put_block_group_ref(&bg_ref);
 530                         return r;
 531                 }
 532
 533         next_group:
 534                 r = ext4_fs_put_block_group_ref(&bg_ref);
 535                 if (r != EOK) {
 536                         return r;
 537                 }
 538
 539                 /* Goto next group */
 540                 bgid = (bgid + 1) % block_group_count;
 541                 count--;
 542         }
 543
 544         return ENOSPC;
 545
 546 success:
 547     /* Empty command - because of syntax */
 548     ;
 549
 550         uint32_t block_size = ext4_sb_get_block_size(sb);
 551
 552         /* Update superblock free blocks count */
 553         uint64_t sb_free_blocks = ext4_sb_get_free_blocks_cnt(sb);
 554         sb_free_blocks--;
 555         ext4_sb_set_free_blocks_cnt(sb, sb_free_blocks);
 556
 557         /* Update inode blocks (different block size!) count */
 558         uint64_t ino_blocks = ext4_inode_get_blocks_count(sb, inode_ref->inode);
 559         ino_blocks += block_size / EXT4_INODE_BLOCK_SIZE;
 560         ext4_inode_set_blocks_count(sb, inode_ref->inode, ino_blocks);
 561         inode_ref->dirty = true;
 562
 563         /* Update block group free blocks count */
 564
 565         uint32_t fb_cnt = ext4_bg_get_free_blocks_count(bg_ref.block_group, sb);
 566         fb_cnt--;
 567         ext4_bg_set_free_blocks_count(bg_ref.block_group, sb, fb_cnt);
 568
 569         bg_ref.dirty = true;
 570         r = ext4_fs_put_block_group_ref(&bg_ref);
 571
 572         *fblock = alloc;
 573         return r;
 574 }
 575
 576 int ext4_balloc_try_alloc_block(struct ext4_inode_ref *inode_ref,
 577                                 ext4_fsblk_t baddr, bool *free)
 578 {
 579         int rc;
 580
 581         struct ext4_fs *fs = inode_ref->fs;
 582         struct ext4_sblock *sb = &fs->sb;
 583
 584         /* Compute indexes */
 585         uint32_t block_group = ext4_balloc_get_bgid_of_block(sb, baddr);
 586         uint32_t index_in_group = ext4_fs_addr_to_idx_bg(sb, baddr);
 587
 588         /* Load block group reference */
 589         struct ext4_block_group_ref bg_ref;
 590         rc = ext4_fs_get_block_group_ref(fs, block_group, &bg_ref);
 591         if (rc != EOK)
 592                 return rc;
 593
 594         /* Load block with bitmap */
 595         ext4_fsblk_t bmp_blk_addr;
 596         bmp_blk_addr = ext4_bg_get_block_bitmap(bg_ref.block_group, sb);
 597
 598         struct ext4_block b;
 599         rc = ext4_trans_block_get(fs->bdev, &b, bmp_blk_addr);
 600         if (rc != EOK) {
 601                 ext4_fs_put_block_group_ref(&bg_ref);
 602                 return rc;
 603         }
 604
 605         if (!ext4_balloc_verify_bitmap_csum(sb, bg_ref.block_group, b.data)) {
 606                 ext4_dbg(DEBUG_BALLOC,
 607                         DBG_WARN "Bitmap checksum failed."
 608                         "Group: %" PRIu32"\n",
 609                         bg_ref.index);
 610         }
 611
 612         /* Check if block is free */
 613         *free = ext4_bmap_is_bit_clr(b.data, index_in_group);
 614
 615         /* Allocate block if possible */
 616         if (*free) {
 617                 ext4_bmap_bit_set(b.data, index_in_group);
 618                 ext4_balloc_set_bitmap_csum(sb, bg_ref.block_group, b.data);
 619                 ext4_trans_set_block_dirty(b.buf);
 620         }
 621
 622         /* Release block with bitmap */
 623         rc = ext4_block_set(fs->bdev, &b);
 624         if (rc != EOK) {
 625                 /* Error in saving bitmap */
 626                 ext4_fs_put_block_group_ref(&bg_ref);
 627                 return rc;
 628         }
 629
 630         /* If block is not free, return */
 631         if (!(*free))
 632                 goto terminate;
 633
 634         uint32_t block_size = ext4_sb_get_block_size(sb);
 635
 636         /* Update superblock free blocks count */
 637         uint64_t sb_free_blocks = ext4_sb_get_free_blocks_cnt(sb);
 638         sb_free_blocks--;
 639         ext4_sb_set_free_blocks_cnt(sb, sb_free_blocks);
 640
 641         /* Update inode blocks count */
 642         uint64_t ino_blocks = ext4_inode_get_blocks_count(sb, inode_ref->inode);
 643         ino_blocks += block_size / EXT4_INODE_BLOCK_SIZE;
 644         ext4_inode_set_blocks_count(sb, inode_ref->inode, ino_blocks);
 645         inode_ref->dirty = true;
 646
 647         /* Update block group free blocks count */
 648         uint32_t fb_cnt = ext4_bg_get_free_blocks_count(bg_ref.block_group, sb);
 649         fb_cnt--;
 650         ext4_bg_set_free_blocks_count(bg_ref.block_group, sb, fb_cnt);
 651
 652         bg_ref.dirty = true;
 653
 654 terminate:
 655         return ext4_fs_put_block_group_ref(&bg_ref);
 656 }
 657
 658 /**
 659  * @}
 660  */