resize/resize2fs.c

   1 /*
   2  * resize2fs.c --- ext2 main routine
   3  *
   4  * Copyright (C) 1997, 1998 by Theodore Ts'o and
   5  *      PowerQuest, Inc.
   6  *
   7  * Copyright (C) 1999, 2000 by Theosore Ts'o
   8  *
   9  * %Begin-Header%
  10  * This file may be redistributed under the terms of the GNU Public
  11  * License.
  12  * %End-Header%
  13  */
  14
  15 /*
  16  * Resizing a filesystem consists of the following phases:
  17  *
  18  *      1.  Adjust superblock and write out new parts of the inode
  19  *              table
  20  *      2.  Determine blocks which need to be relocated, and copy the
  21  *              contents of blocks from their old locations to the new ones.
  22  *      3.  Scan the inode table, doing the following:
  23  *              a.  If blocks have been moved, update the block
  24  *                      pointers in the inodes and indirect blocks to
  25  *                      point at the new block locations.
  26  *              b.  If parts of the inode table need to be evacuated,
  27  *                      copy inodes from their old locations to their
  28  *                      new ones.
  29  *              c.  If (b) needs to be done, note which blocks contain
  30  *                      directory information, since we will need to
  31  *                      update the directory information.
  32  *      4.  Update the directory blocks with the new inode locations.
  33  *      5.  Move the inode tables, if necessary.
  34  */
  35
  36 #include "config.h"
  37 #include "resize2fs.h"
  38 #include <time.h>
  39
  40 #ifdef __linux__                        /* Kludge for debugging */
  41 #define RESIZE2FS_DEBUG
  42 #endif
  43
  44 static void fix_uninit_block_bitmaps(ext2_filsys fs);
  45 static errcode_t adjust_superblock(ext2_resize_t rfs, blk64_t new_size);
  46 static errcode_t blocks_to_move(ext2_resize_t rfs);
  47 static errcode_t block_mover(ext2_resize_t rfs);
  48 static errcode_t inode_scan_and_fix(ext2_resize_t rfs);
  49 static errcode_t inode_ref_fix(ext2_resize_t rfs);
  50 static errcode_t move_itables(ext2_resize_t rfs);
  51 static errcode_t fix_resize_inode(ext2_filsys fs);
  52 static errcode_t ext2fs_calculate_summary_stats(ext2_filsys fs);
  53 static errcode_t fix_sb_journal_backup(ext2_filsys fs);
  54
  55 /*
  56  * Some helper CPP macros
  57  */
  58 #define IS_BLOCK_BM(fs, i, blk) ((blk) == ext2fs_block_bitmap_loc((fs),(i)))
  59 #define IS_INODE_BM(fs, i, blk) ((blk) == ext2fs_inode_bitmap_loc((fs),(i)))
  60
  61 #define IS_INODE_TB(fs, i, blk) (((blk) >= ext2fs_inode_table_loc((fs), (i))) && \
  62                                  ((blk) < (ext2fs_inode_table_loc((fs), (i)) + \
  63                                            (fs)->inode_blocks_per_group)))
  64
  65 int lazy_itable_init;
  66
  67 /*
  68  * This is the top-level routine which does the dirty deed....
  69  */
  70 errcode_t resize_fs(ext2_filsys fs, blk64_t *new_size, int flags,
  71             errcode_t (*progress)(ext2_resize_t rfs, int pass,
  72                                           unsigned long cur,
  73                                           unsigned long max_val))
  74 {
  75         ext2_resize_t   rfs;
  76         errcode_t       retval;
  77
  78         retval = ext2fs_read_bitmaps(fs);
  79         if (retval)
  80                 return retval;
  81
  82         fs->super->s_state |= EXT2_ERROR_FS;
  83         ext2fs_mark_super_dirty(fs);
  84         ext2fs_flush(fs);
  85
  86         /*
  87          * Create the data structure
  88          */
  89         retval = ext2fs_get_mem(sizeof(struct ext2_resize_struct), &rfs);
  90         if (retval)
  91                 return retval;
  92         memset(rfs, 0, sizeof(struct ext2_resize_struct));
  93
  94         fix_uninit_block_bitmaps(fs);
  95         fs->priv_data = rfs;
  96         rfs->old_fs = fs;
  97         rfs->flags = flags;
  98         rfs->itable_buf  = 0;
  99         rfs->progress = progress;
 100         retval = ext2fs_dup_handle(fs, &rfs->new_fs);
 101         if (retval)
 102                 goto errout;
 103
 104         retval = adjust_superblock(rfs, *new_size);
 105         if (retval)
 106                 goto errout;
 107
 108         fix_uninit_block_bitmaps(rfs->new_fs);
 109         /* Clear the block bitmap uninit flag for the last block group */
 110         ext2fs_bg_flags_clear(rfs->new_fs, rfs->new_fs->group_desc_count - 1,
 111                              EXT2_BG_BLOCK_UNINIT);
 112
 113         *new_size = ext2fs_blocks_count(rfs->new_fs->super);
 114
 115         retval = blocks_to_move(rfs);
 116         if (retval)
 117                 goto errout;
 118
 119 #ifdef RESIZE2FS_DEBUG
 120         if (rfs->flags & RESIZE_DEBUG_BMOVE)
 121                 printf("Number of free blocks: %llu/%llu, Needed: %llu\n",
 122                        ext2fs_free_blocks_count(rfs->old_fs->super),
 123                        ext2fs_free_blocks_count(rfs->new_fs->super),
 124                        rfs->needed_blocks);
 125 #endif
 126
 127         retval = block_mover(rfs);
 128         if (retval)
 129                 goto errout;
 130
 131         retval = inode_scan_and_fix(rfs);
 132         if (retval)
 133                 goto errout;
 134
 135         retval = inode_ref_fix(rfs);
 136         if (retval)
 137                 goto errout;
 138
 139         retval = move_itables(rfs);
 140         if (retval)
 141                 goto errout;
 142
 143         retval = ext2fs_calculate_summary_stats(rfs->new_fs);
 144         if (retval)
 145                 goto errout;
 146
 147         retval = fix_resize_inode(rfs->new_fs);
 148         if (retval)
 149                 goto errout;
 150
 151         retval = fix_sb_journal_backup(rfs->new_fs);
 152         if (retval)
 153                 goto errout;
 154
 155         rfs->new_fs->super->s_state &= ~EXT2_ERROR_FS;
 156         rfs->new_fs->flags &= ~EXT2_FLAG_MASTER_SB_ONLY;
 157         retval = ext2fs_close(rfs->new_fs);
 158         if (retval)
 159                 goto errout;
 160
 161         rfs->flags = flags;
 162
 163         ext2fs_free(rfs->old_fs);
 164         if (rfs->itable_buf)
 165                 ext2fs_free_mem(&rfs->itable_buf);
 166         if (rfs->reserve_blocks)
 167                 ext2fs_free_block_bitmap(rfs->reserve_blocks);
 168         if (rfs->move_blocks)
 169                 ext2fs_free_block_bitmap(rfs->move_blocks);
 170         ext2fs_free_mem(&rfs);
 171
 172         return 0;
 173
 174 errout:
 175         if (rfs->new_fs)
 176                 ext2fs_free(rfs->new_fs);
 177         if (rfs->itable_buf)
 178                 ext2fs_free_mem(&rfs->itable_buf);
 179         ext2fs_free_mem(&rfs);
 180         return retval;
 181 }
 182
 183 /*
 184  * Clean up the bitmaps for unitialized bitmaps
 185  */
 186 static void fix_uninit_block_bitmaps(ext2_filsys fs)
 187 {
 188         blk64_t         i, blk, super_blk, old_desc_blk, new_desc_blk;
 189         int             old_desc_blocks;
 190         dgrp_t          g;
 191
 192         if (!(EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
 193                                          EXT4_FEATURE_RO_COMPAT_GDT_CSUM)))
 194                 return;
 195
 196         for (g=0; g < fs->group_desc_count; g++) {
 197                 if (!(ext2fs_bg_flags_test(fs, g, EXT2_BG_BLOCK_UNINIT)))
 198                         continue;
 199
 200                 blk = ext2fs_group_first_block2(fs, g);
 201
 202                 ext2fs_super_and_bgd_loc2(fs, g, &super_blk,
 203                                           &old_desc_blk, &new_desc_blk, 0);
 204
 205                 if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
 206                         old_desc_blocks = fs->super->s_first_meta_bg;
 207                 else
 208                         old_desc_blocks = fs->desc_blocks +
 209                                 fs->super->s_reserved_gdt_blocks;
 210
 211                 for (i=0; i < fs->super->s_blocks_per_group; i++, blk++) {
 212                         if (blk >= ext2fs_blocks_count(fs->super))
 213                                 break;
 214                         if ((blk == super_blk) ||
 215                             (old_desc_blk && old_desc_blocks &&
 216                              (blk >= old_desc_blk) &&
 217                              (blk < old_desc_blk + old_desc_blocks)) ||
 218                             (new_desc_blk && (blk == new_desc_blk)) ||
 219                             (blk == ext2fs_block_bitmap_loc(fs, g)) ||
 220                             (blk == ext2fs_inode_bitmap_loc(fs, g)) ||
 221                             (blk >= ext2fs_inode_table_loc(fs, g) &&
 222                              (blk < ext2fs_inode_table_loc(fs, g)
 223                               + fs->inode_blocks_per_group)))
 224                                 ext2fs_fast_mark_block_bitmap2(fs->block_map, blk);
 225                         else
 226                                 ext2fs_fast_unmark_block_bitmap2(fs->block_map, blk);
 227                 }
 228         }
 229 }
 230
 231 /* --------------------------------------------------------------------
 232  *
 233  * Resize processing, phase 1.
 234  *
 235  * In this phase we adjust the in-memory superblock information, and
 236  * initialize any new parts of the inode table.  The new parts of the
 237  * inode table are created in virgin disk space, so we can abort here
 238  * without any side effects.
 239  * --------------------------------------------------------------------
 240  */
 241
 242 /*
 243  * If the group descriptor's bitmap and inode table blocks are valid,
 244  * release them in the new filesystem data structure, and mark them as
 245  * reserved so the old inode table blocks don't get overwritten.
 246  */
 247 static void free_gdp_blocks(ext2_filsys fs,
 248                             ext2fs_block_bitmap reserve_blocks,
 249                             struct ext2_group_desc *gdp)
 250 {
 251         blk_t   blk;
 252         int     j;
 253
 254         if (gdp->bg_block_bitmap &&
 255             (gdp->bg_block_bitmap < ext2fs_blocks_count(fs->super))) {
 256                 ext2fs_block_alloc_stats(fs, gdp->bg_block_bitmap, -1);
 257                 ext2fs_mark_block_bitmap2(reserve_blocks,
 258                                          gdp->bg_block_bitmap);
 259         }
 260
 261         if (gdp->bg_inode_bitmap &&
 262             (gdp->bg_inode_bitmap < ext2fs_blocks_count(fs->super))) {
 263                 ext2fs_block_alloc_stats(fs, gdp->bg_inode_bitmap, -1);
 264                 ext2fs_mark_block_bitmap2(reserve_blocks,
 265                                          gdp->bg_inode_bitmap);
 266         }
 267
 268         if (gdp->bg_inode_table == 0 ||
 269             (gdp->bg_inode_table >= ext2fs_blocks_count(fs->super)))
 270                 return;
 271
 272         for (blk = gdp->bg_inode_table, j = 0;
 273              j < fs->inode_blocks_per_group; j++, blk++) {
 274                 if (blk >= ext2fs_blocks_count(fs->super))
 275                         break;
 276                 ext2fs_block_alloc_stats(fs, blk, -1);
 277                 ext2fs_mark_block_bitmap2(reserve_blocks, blk);
 278         }
 279 }
 280
 281 /*
 282  * This routine is shared by the online and offline resize routines.
 283  * All of the information which is adjusted in memory is done here.
 284  *
 285  * The reserve_blocks parameter is only needed when shrinking the
 286  * filesystem.
 287  */
 288 errcode_t adjust_fs_info(ext2_filsys fs, ext2_filsys old_fs,
 289                          ext2fs_block_bitmap reserve_blocks, blk64_t new_size)
 290 {
 291         errcode_t       retval;
 292         blk64_t         overhead = 0;
 293         blk64_t         rem;
 294         blk64_t         blk, group_block;
 295         blk64_t         real_end;
 296         blk64_t         old_numblocks, numblocks, adjblocks;
 297         unsigned long   i, j, old_desc_blocks;
 298         unsigned int    meta_bg, meta_bg_size;
 299         int             has_super, csum_flag;
 300         unsigned long long new_inodes;  /* u64 to check for overflow */
 301         double          percent;
 302
 303         ext2fs_blocks_count_set(fs->super, new_size);
 304
 305 retry:
 306         fs->group_desc_count = ext2fs_div64_ceil(ext2fs_blocks_count(fs->super) -
 307                                        fs->super->s_first_data_block,
 308                                        EXT2_BLOCKS_PER_GROUP(fs->super));
 309         if (fs->group_desc_count == 0)
 310                 return EXT2_ET_TOOSMALL;
 311         fs->desc_blocks = ext2fs_div_ceil(fs->group_desc_count,
 312                                           EXT2_DESC_PER_BLOCK(fs->super));
 313
 314         /*
 315          * Overhead is the number of bookkeeping blocks per group.  It
 316          * includes the superblock backup, the group descriptor
 317          * backups, the inode bitmap, the block bitmap, and the inode
 318          * table.
 319          */
 320         overhead = (int) (2 + fs->inode_blocks_per_group);
 321
 322         if (ext2fs_bg_has_super(fs, fs->group_desc_count - 1))
 323                 overhead += 1 + fs->desc_blocks +
 324                         fs->super->s_reserved_gdt_blocks;
 325
 326         /*
 327          * See if the last group is big enough to support the
 328          * necessary data structures.  If not, we need to get rid of
 329          * it.
 330          */
 331         rem = (ext2fs_blocks_count(fs->super) - fs->super->s_first_data_block) %
 332                 fs->super->s_blocks_per_group;
 333         if ((fs->group_desc_count == 1) && rem && (rem < overhead))
 334                 return EXT2_ET_TOOSMALL;
 335         if ((fs->group_desc_count > 1) && rem && (rem < overhead+50)) {
 336                 ext2fs_blocks_count_set(fs->super,
 337                                         ext2fs_blocks_count(fs->super) - rem);
 338                 goto retry;
 339         }
 340         /*
 341          * Adjust the number of inodes
 342          */
 343         new_inodes =(unsigned long long) fs->super->s_inodes_per_group * fs->group_desc_count;
 344         if (new_inodes > ~0U) {
 345                 fprintf(stderr, _("inodes (%llu) must be less than %u"),
 346                                    new_inodes, ~0U);
 347                 return EXT2_ET_TOO_MANY_INODES;
 348         }
 349         fs->super->s_inodes_count = fs->super->s_inodes_per_group *
 350                 fs->group_desc_count;
 351
 352         /*
 353          * Adjust the number of free blocks
 354          */
 355         blk = ext2fs_blocks_count(old_fs->super);
 356         if (blk > ext2fs_blocks_count(fs->super))
 357                 ext2fs_free_blocks_count_set(fs->super,
 358                         ext2fs_free_blocks_count(fs->super) -
 359                         (blk - ext2fs_blocks_count(fs->super)));
 360         else
 361                 ext2fs_free_blocks_count_set(fs->super,
 362                         ext2fs_free_blocks_count(fs->super) +
 363                         (ext2fs_blocks_count(fs->super) - blk));
 364
 365         /*
 366          * Adjust the number of reserved blocks
 367          */
 368         percent = (ext2fs_r_blocks_count(old_fs->super) * 100.0) /
 369                 ext2fs_blocks_count(old_fs->super);
 370         ext2fs_r_blocks_count_set(fs->super,
 371                                   (percent * ext2fs_blocks_count(fs->super) /
 372                                    100.0));
 373
 374         /*
 375          * Adjust the bitmaps for size
 376          */
 377         retval = ext2fs_resize_inode_bitmap2(fs->super->s_inodes_count,
 378                                             fs->super->s_inodes_count,
 379                                             fs->inode_map);
 380         if (retval) goto errout;
 381
 382         real_end = (((blk64_t) EXT2_BLOCKS_PER_GROUP(fs->super) *
 383                      fs->group_desc_count)) - 1 +
 384                 fs->super->s_first_data_block;
 385         retval = ext2fs_resize_block_bitmap2(ext2fs_blocks_count(fs->super)-1,
 386                                             real_end, fs->block_map);
 387
 388         if (retval) goto errout;
 389
 390         /*
 391          * Reallocate the group descriptors as necessary.
 392          */
 393         if (old_fs->desc_blocks != fs->desc_blocks) {
 394                 retval = ext2fs_resize_mem(old_fs->desc_blocks *
 395                                            fs->blocksize,
 396                                            fs->desc_blocks * fs->blocksize,
 397                                            &fs->group_desc);
 398                 if (retval)
 399                         goto errout;
 400                 if (fs->desc_blocks > old_fs->desc_blocks)
 401                         memset((char *) fs->group_desc +
 402                                (old_fs->desc_blocks * fs->blocksize), 0,
 403                                (fs->desc_blocks - old_fs->desc_blocks) *
 404                                fs->blocksize);
 405         }
 406
 407         /*
 408          * If the resize_inode feature is set, and we are changing the
 409          * number of descriptor blocks, then adjust
 410          * s_reserved_gdt_blocks if possible to avoid needing to move
 411          * the inode table either now or in the future.
 412          */
 413         if ((fs->super->s_feature_compat &
 414              EXT2_FEATURE_COMPAT_RESIZE_INODE) &&
 415             (old_fs->desc_blocks != fs->desc_blocks)) {
 416                 int new;
 417
 418                 new = ((int) fs->super->s_reserved_gdt_blocks) +
 419                         (old_fs->desc_blocks - fs->desc_blocks);
 420                 if (new < 0)
 421                         new = 0;
 422                 if (new > (int) fs->blocksize/4)
 423                         new = fs->blocksize/4;
 424                 fs->super->s_reserved_gdt_blocks = new;
 425         }
 426
 427         /*
 428          * If we are shrinking the number of block groups, we're done
 429          * and can exit now.
 430          */
 431         if (old_fs->group_desc_count > fs->group_desc_count) {
 432                 /*
 433                  * Check the block groups that we are chopping off
 434                  * and free any blocks associated with their metadata
 435                  */
 436                 for (i = fs->group_desc_count;
 437                      i < old_fs->group_desc_count; i++) {
 438                         free_gdp_blocks(fs, reserve_blocks,
 439                                         ext2fs_group_desc(old_fs,
 440                                                 old_fs->group_desc, i));
 441                 }
 442                 retval = 0;
 443                 goto errout;
 444         }
 445
 446         /*
 447          * Fix the count of the last (old) block group
 448          */
 449         old_numblocks = (ext2fs_blocks_count(old_fs->super) -
 450                          old_fs->super->s_first_data_block) %
 451                                  old_fs->super->s_blocks_per_group;
 452         if (!old_numblocks)
 453                 old_numblocks = old_fs->super->s_blocks_per_group;
 454         if (old_fs->group_desc_count == fs->group_desc_count) {
 455                 numblocks = (ext2fs_blocks_count(fs->super) -
 456                              fs->super->s_first_data_block) %
 457                         fs->super->s_blocks_per_group;
 458                 if (!numblocks)
 459                         numblocks = fs->super->s_blocks_per_group;
 460         } else
 461                 numblocks = fs->super->s_blocks_per_group;
 462         i = old_fs->group_desc_count - 1;
 463         ext2fs_bg_free_blocks_count_set(fs, i, ext2fs_bg_free_blocks_count(fs, i) + (numblocks - old_numblocks));
 464         ext2fs_group_desc_csum_set(fs, i);
 465
 466         /*
 467          * If the number of block groups is staying the same, we're
 468          * done and can exit now.  (If the number block groups is
 469          * shrinking, we had exited earlier.)
 470          */
 471         if (old_fs->group_desc_count >= fs->group_desc_count) {
 472                 retval = 0;
 473                 goto errout;
 474         }
 475
 476         /*
 477          * Initialize the new block group descriptors
 478          */
 479         group_block = fs->super->s_first_data_block +
 480                 old_fs->group_desc_count * fs->super->s_blocks_per_group;
 481
 482         csum_flag = EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
 483                                                EXT4_FEATURE_RO_COMPAT_GDT_CSUM);
 484         if (access("/sys/fs/ext4/features/lazy_itable_init", F_OK) == 0)
 485                 lazy_itable_init = 1;
 486         if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
 487                 old_desc_blocks = fs->super->s_first_meta_bg;
 488         else
 489                 old_desc_blocks = fs->desc_blocks +
 490                         fs->super->s_reserved_gdt_blocks;
 491         for (i = old_fs->group_desc_count;
 492              i < fs->group_desc_count; i++) {
 493                 memset(ext2fs_group_desc(fs, fs->group_desc, i), 0,
 494                        sizeof(struct ext2_group_desc));
 495                 adjblocks = 0;
 496
 497                 ext2fs_bg_flags_zap(fs, i);
 498                 if (csum_flag) {
 499                         ext2fs_bg_flags_set(fs, i, EXT2_BG_INODE_UNINIT);
 500                         if (!lazy_itable_init)
 501                                 ext2fs_bg_flags_set(fs, i,
 502                                                     EXT2_BG_INODE_ZEROED);
 503                         ext2fs_bg_itable_unused_set(fs, i,
 504                                         fs->super->s_inodes_per_group);
 505                 }
 506
 507                 numblocks = ext2fs_group_blocks_count(fs, i);
 508                 if ((i < fs->group_desc_count - 1) && csum_flag)
 509                         ext2fs_bg_flags_set(fs, i, EXT2_BG_BLOCK_UNINIT);
 510
 511                 has_super = ext2fs_bg_has_super(fs, i);
 512                 if (has_super) {
 513                         ext2fs_block_alloc_stats2(fs, group_block, +1);
 514                         adjblocks++;
 515                 }
 516                 meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
 517                 meta_bg = i / meta_bg_size;
 518                 if (!(fs->super->s_feature_incompat &
 519                       EXT2_FEATURE_INCOMPAT_META_BG) ||
 520                     (meta_bg < fs->super->s_first_meta_bg)) {
 521                         if (has_super) {
 522                                 for (j=0; j < old_desc_blocks; j++)
 523                                         ext2fs_block_alloc_stats2(fs,
 524                                                  group_block + 1 + j, +1);
 525                                 adjblocks += old_desc_blocks;
 526                         }
 527                 } else {
 528                         if (has_super)
 529                                 has_super = 1;
 530                         if (((i % meta_bg_size) == 0) ||
 531                             ((i % meta_bg_size) == 1) ||
 532                             ((i % meta_bg_size) == (meta_bg_size-1)))
 533                                 ext2fs_block_alloc_stats2(fs,
 534                                                  group_block + has_super, +1);
 535                 }
 536
 537                 adjblocks += 2 + fs->inode_blocks_per_group;
 538
 539                 numblocks -= adjblocks;
 540                 ext2fs_free_blocks_count_set(fs->super,
 541                              ext2fs_free_blocks_count(fs->super) - adjblocks);
 542                 fs->super->s_free_inodes_count +=
 543                         fs->super->s_inodes_per_group;
 544                 ext2fs_bg_free_blocks_count_set(fs, i, numblocks);
 545                 ext2fs_bg_free_inodes_count_set(fs, i,
 546                                                 fs->super->s_inodes_per_group);
 547                 ext2fs_bg_used_dirs_count_set(fs, i, 0);
 548                 ext2fs_group_desc_csum_set(fs, i);
 549
 550                 retval = ext2fs_allocate_group_table(fs, i, 0);
 551                 if (retval) goto errout;
 552
 553                 group_block += fs->super->s_blocks_per_group;
 554         }
 555         retval = 0;
 556
 557 errout:
 558         return (retval);
 559 }
 560
 561 /*
 562  * This routine adjusts the superblock and other data structures, both
 563  * in disk as well as in memory...
 564  */
 565 static errcode_t adjust_superblock(ext2_resize_t rfs, blk64_t new_size)
 566 {
 567         ext2_filsys fs;
 568         int             adj = 0;
 569         errcode_t       retval;
 570         blk64_t         group_block;
 571         unsigned long   i;
 572         unsigned long   max_group;
 573
 574         fs = rfs->new_fs;
 575         ext2fs_mark_super_dirty(fs);
 576         ext2fs_mark_bb_dirty(fs);
 577         ext2fs_mark_ib_dirty(fs);
 578
 579         retval = ext2fs_allocate_block_bitmap(fs, _("reserved blocks"),
 580                                               &rfs->reserve_blocks);
 581         if (retval)
 582                 return retval;
 583
 584         retval = adjust_fs_info(fs, rfs->old_fs, rfs->reserve_blocks, new_size);
 585         if (retval)
 586                 goto errout;
 587
 588         /*
 589          * Check to make sure there are enough inodes
 590          */
 591         if ((rfs->old_fs->super->s_inodes_count -
 592              rfs->old_fs->super->s_free_inodes_count) >
 593             rfs->new_fs->super->s_inodes_count) {
 594                 retval = ENOSPC;
 595                 goto errout;
 596         }
 597
 598         /*
 599          * If we are shrinking the number block groups, we're done and
 600          * can exit now.
 601          */
 602         if (rfs->old_fs->group_desc_count > fs->group_desc_count) {
 603                 retval = 0;
 604                 goto errout;
 605         }
 606
 607         /*
 608          * If the number of block groups is staying the same, we're
 609          * done and can exit now.  (If the number block groups is
 610          * shrinking, we had exited earlier.)
 611          */
 612         if (rfs->old_fs->group_desc_count >= fs->group_desc_count) {
 613                 retval = 0;
 614                 goto errout;
 615         }
 616
 617         /*
 618          * If we are using uninit_bg (aka GDT_CSUM) and the kernel
 619          * supports lazy inode initialization, we can skip
 620          * initializing the inode table.
 621          */
 622         if (lazy_itable_init &&
 623             EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
 624                                        EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
 625                 retval = 0;
 626                 goto errout;
 627         }
 628
 629         /*
 630          * Initialize the inode table
 631          */
 632         retval = ext2fs_get_array(fs->blocksize, fs->inode_blocks_per_group,
 633                                 &rfs->itable_buf);
 634         if (retval)
 635                 goto errout;
 636
 637         memset(rfs->itable_buf, 0, fs->blocksize * fs->inode_blocks_per_group);
 638         group_block = fs->super->s_first_data_block +
 639                 rfs->old_fs->group_desc_count * fs->super->s_blocks_per_group;
 640
 641         adj = rfs->old_fs->group_desc_count;
 642         max_group = fs->group_desc_count - adj;
 643         if (rfs->progress) {
 644                 retval = rfs->progress(rfs, E2_RSZ_EXTEND_ITABLE_PASS,
 645                                        0, max_group);
 646                 if (retval)
 647                         goto errout;
 648         }
 649         for (i = rfs->old_fs->group_desc_count;
 650              i < fs->group_desc_count; i++) {
 651                 /*
 652                  * Write out the new inode table
 653                  */
 654                 retval = io_channel_write_blk64(fs->io,
 655                                                 ext2fs_inode_table_loc(fs, i),
 656                                                 fs->inode_blocks_per_group,
 657                                                 rfs->itable_buf);
 658                 if (retval) goto errout;
 659
 660                 io_channel_flush(fs->io);
 661                 if (rfs->progress) {
 662                         retval = rfs->progress(rfs, E2_RSZ_EXTEND_ITABLE_PASS,
 663                                                i - adj + 1, max_group);
 664                         if (retval)
 665                                 goto errout;
 666                 }
 667                 group_block += fs->super->s_blocks_per_group;
 668         }
 669         io_channel_flush(fs->io);
 670         retval = 0;
 671
 672 errout:
 673         return retval;
 674 }
 675
 676 /* --------------------------------------------------------------------
 677  *
 678  * Resize processing, phase 2.
 679  *
 680  * In this phase we adjust determine which blocks need to be moved, in
 681  * blocks_to_move().  We then copy the blocks to their ultimate new
 682  * destinations using block_mover().  Since we are copying blocks to
 683  * their new locations, again during this pass we can abort without
 684  * any problems.
 685  * --------------------------------------------------------------------
 686  */
 687
 688 /*
 689  * This helper function creates a block bitmap with all of the
 690  * filesystem meta-data blocks.
 691  */
 692 static errcode_t mark_table_blocks(ext2_filsys fs,
 693                                    ext2fs_block_bitmap bmap)
 694 {
 695         blk64_t                 b;
 696         unsigned int            j;
 697         dgrp_t                  i;
 698
 699         for (i = 0; i < fs->group_desc_count; i++) {
 700                 ext2fs_reserve_super_and_bgd(fs, i, bmap);
 701
 702                 /*
 703                  * Mark the blocks used for the inode table
 704                  */
 705                 for (j = 0, b = ext2fs_inode_table_loc(fs, i);
 706                      j < (unsigned int) fs->inode_blocks_per_group;
 707                      j++, b++)
 708                         ext2fs_mark_block_bitmap2(bmap, b);
 709
 710                 /*
 711                  * Mark block used for the block bitmap
 712                  */
 713                 ext2fs_mark_block_bitmap2(bmap,
 714                                          ext2fs_block_bitmap_loc(fs, i));
 715
 716                 /*
 717                  * Mark block used for the inode bitmap
 718                  */
 719                 ext2fs_mark_block_bitmap2(bmap,
 720                                          ext2fs_inode_bitmap_loc(fs, i));
 721         }
 722         return 0;
 723 }
 724
 725 /*
 726  * This function checks to see if a particular block (either a
 727  * superblock or a block group descriptor) overlaps with an inode or
 728  * block bitmap block, or with the inode table.
 729  */
 730 static void mark_fs_metablock(ext2_resize_t rfs,
 731                               ext2fs_block_bitmap meta_bmap,
 732                               int group, blk64_t blk)
 733 {
 734         ext2_filsys     fs = rfs->new_fs;
 735
 736         ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
 737         ext2fs_block_alloc_stats2(fs, blk, +1);
 738
 739         /*
 740          * Check to see if we overlap with the inode or block bitmap,
 741          * or the inode tables.  If not, and the block is in use, then
 742          * mark it as a block to be moved.
 743          */
 744         if (IS_BLOCK_BM(fs, group, blk)) {
 745                 ext2fs_block_bitmap_loc_set(fs, group, 0);
 746                 rfs->needed_blocks++;
 747                 return;
 748         }
 749         if (IS_INODE_BM(fs, group, blk)) {
 750                 ext2fs_inode_bitmap_loc_set(fs, group, 0);
 751                 rfs->needed_blocks++;
 752                 return;
 753         }
 754         if (IS_INODE_TB(fs, group, blk)) {
 755                 ext2fs_inode_table_loc_set(fs, group, 0);
 756                 rfs->needed_blocks++;
 757                 return;
 758         }
 759         if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_FLEX_BG) {
 760                 dgrp_t i;
 761
 762                 for (i=0; i < rfs->old_fs->group_desc_count; i++) {
 763                         if (IS_BLOCK_BM(fs, i, blk)) {
 764                                 ext2fs_block_bitmap_loc_set(fs, i, 0);
 765                                 rfs->needed_blocks++;
 766                                 return;
 767                         }
 768                         if (IS_INODE_BM(fs, i, blk)) {
 769                                 ext2fs_inode_bitmap_loc_set(fs, i, 0);
 770                                 rfs->needed_blocks++;
 771                                 return;
 772                         }
 773                         if (IS_INODE_TB(fs, i, blk)) {
 774                                 ext2fs_inode_table_loc_set(fs, i, 0);
 775                                 rfs->needed_blocks++;
 776                                 return;
 777                         }
 778                 }
 779         }
 780         if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
 781                                        EXT4_FEATURE_RO_COMPAT_GDT_CSUM) &&
 782                    (ext2fs_bg_flags_test(fs, group, EXT2_BG_BLOCK_UNINIT))) {
 783                 /*
 784                  * If the block bitmap is uninitialized, which means
 785                  * nothing other than standard metadata in use.
 786                  */
 787                 return;
 788         } else if (ext2fs_test_block_bitmap2(rfs->old_fs->block_map, blk) &&
 789                    !ext2fs_test_block_bitmap2(meta_bmap, blk)) {
 790                 ext2fs_mark_block_bitmap2(rfs->move_blocks, blk);
 791                 rfs->needed_blocks++;
 792         }
 793 }
 794
 795
 796 /*
 797  * This routine marks and unmarks reserved blocks in the new block
 798  * bitmap.  It also determines which blocks need to be moved and
 799  * places this information into the move_blocks bitmap.
 800  */
 801 static errcode_t blocks_to_move(ext2_resize_t rfs)
 802 {
 803         int             j, has_super;
 804         dgrp_t          i, max_groups, g;
 805         blk64_t         blk, group_blk;
 806         blk64_t         old_blocks, new_blocks;
 807         unsigned int    meta_bg, meta_bg_size;
 808         errcode_t       retval;
 809         ext2_filsys     fs, old_fs;
 810         ext2fs_block_bitmap     meta_bmap;
 811         int             flex_bg;
 812
 813         fs = rfs->new_fs;
 814         old_fs = rfs->old_fs;
 815         if (ext2fs_blocks_count(old_fs->super) > ext2fs_blocks_count(fs->super))
 816                 fs = rfs->old_fs;
 817
 818         retval = ext2fs_allocate_block_bitmap(fs, _("blocks to be moved"),
 819                                               &rfs->move_blocks);
 820         if (retval)
 821                 return retval;
 822
 823         retval = ext2fs_allocate_block_bitmap(fs, _("meta-data blocks"),
 824                                               &meta_bmap);
 825         if (retval)
 826                 return retval;
 827
 828         retval = mark_table_blocks(old_fs, meta_bmap);
 829         if (retval)
 830                 return retval;
 831
 832         fs = rfs->new_fs;
 833
 834         /*
 835          * If we're shrinking the filesystem, we need to move all of
 836          * the blocks that don't fit any more
 837          */
 838         for (blk = ext2fs_blocks_count(fs->super);
 839              blk < ext2fs_blocks_count(old_fs->super); blk++) {
 840                 g = ext2fs_group_of_blk2(fs, blk);
 841                 if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
 842                                                EXT4_FEATURE_RO_COMPAT_GDT_CSUM) &&
 843                     ext2fs_bg_flags_test(old_fs, g, EXT2_BG_BLOCK_UNINIT)) {
 844                         /*
 845                          * The block bitmap is uninitialized, so skip
 846                          * to the next block group.
 847                          */
 848                         blk = ext2fs_group_first_block2(fs, g+1) - 1;
 849                         continue;
 850                 }
 851                 if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
 852                     !ext2fs_test_block_bitmap2(meta_bmap, blk)) {
 853                         ext2fs_mark_block_bitmap2(rfs->move_blocks, blk);
 854                         rfs->needed_blocks++;
 855                 }
 856                 ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
 857         }
 858
 859         if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG) {
 860                 old_blocks = old_fs->super->s_first_meta_bg;
 861                 new_blocks = fs->super->s_first_meta_bg;
 862         } else {
 863                 old_blocks = old_fs->desc_blocks + old_fs->super->s_reserved_gdt_blocks;
 864                 new_blocks = fs->desc_blocks + fs->super->s_reserved_gdt_blocks;
 865         }
 866
 867         if (old_blocks == new_blocks) {
 868                 retval = 0;
 869                 goto errout;
 870         }
 871
 872         max_groups = fs->group_desc_count;
 873         if (max_groups > old_fs->group_desc_count)
 874                 max_groups = old_fs->group_desc_count;
 875         group_blk = old_fs->super->s_first_data_block;
 876         /*
 877          * If we're reducing the number of descriptor blocks, this
 878          * makes life easy.  :-)   We just have to mark some extra
 879          * blocks as free.
 880          */
 881         if (old_blocks > new_blocks) {
 882                 for (i = 0; i < max_groups; i++) {
 883                         if (!ext2fs_bg_has_super(fs, i)) {
 884                                 group_blk += fs->super->s_blocks_per_group;
 885                                 continue;
 886                         }
 887                         for (blk = group_blk+1+new_blocks;
 888                              blk < group_blk+1+old_blocks; blk++) {
 889                                 ext2fs_block_alloc_stats2(fs, blk, -1);
 890                                 rfs->needed_blocks--;
 891                         }
 892                         group_blk += fs->super->s_blocks_per_group;
 893                 }
 894                 retval = 0;
 895                 goto errout;
 896         }
 897         /*
 898          * If we're increasing the number of descriptor blocks, life
 899          * gets interesting....
 900          */
 901         meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
 902         flex_bg = fs->super->s_feature_incompat &
 903                 EXT4_FEATURE_INCOMPAT_FLEX_BG;
 904         /* first reserve all of the existing fs meta blocks */
 905         for (i = 0; i < max_groups; i++) {
 906                 has_super = ext2fs_bg_has_super(fs, i);
 907                 if (has_super)
 908                         mark_fs_metablock(rfs, meta_bmap, i, group_blk);
 909
 910                 meta_bg = i / meta_bg_size;
 911                 if (!(fs->super->s_feature_incompat &
 912                       EXT2_FEATURE_INCOMPAT_META_BG) ||
 913                     (meta_bg < fs->super->s_first_meta_bg)) {
 914                         if (has_super) {
 915                                 for (blk = group_blk+1;
 916                                      blk < group_blk + 1 + new_blocks; blk++)
 917                                         mark_fs_metablock(rfs, meta_bmap,
 918                                                           i, blk);
 919                         }
 920                 } else {
 921                         if (has_super)
 922                                 has_super = 1;
 923                         if (((i % meta_bg_size) == 0) ||
 924                             ((i % meta_bg_size) == 1) ||
 925                             ((i % meta_bg_size) == (meta_bg_size-1)))
 926                                 mark_fs_metablock(rfs, meta_bmap, i,
 927                                                   group_blk + has_super);
 928                 }
 929
 930                 /*
 931                  * Reserve the existing meta blocks that we know
 932                  * aren't to be moved.
 933                  *
 934                  * For flex_bg file systems, in order to avoid
 935                  * overwriting fs metadata (especially inode table
 936                  * blocks) belonging to a different block group when
 937                  * we are relocating the inode tables, we need to
 938                  * reserve all existing fs metadata blocks.
 939                  */
 940                 if (ext2fs_block_bitmap_loc(fs, i))
 941                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
 942                                  ext2fs_block_bitmap_loc(fs, i));
 943                 else if (flex_bg && i < old_fs->group_desc_count)
 944                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
 945                                  ext2fs_block_bitmap_loc(old_fs, i));
 946
 947                 if (ext2fs_inode_bitmap_loc(fs, i))
 948                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
 949                                  ext2fs_inode_bitmap_loc(fs, i));
 950                 else if (flex_bg && i < old_fs->group_desc_count)
 951                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
 952                                  ext2fs_inode_bitmap_loc(old_fs, i));
 953
 954                 if (ext2fs_inode_table_loc(fs, i))
 955                         for (blk = ext2fs_inode_table_loc(fs, i), j=0;
 956                              j < fs->inode_blocks_per_group ; j++, blk++)
 957                                 ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
 958                                                          blk);
 959                 else if (flex_bg && i < old_fs->group_desc_count)
 960                         for (blk = ext2fs_inode_table_loc(old_fs, i), j=0;
 961                              j < old_fs->inode_blocks_per_group ; j++, blk++)
 962                                 ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
 963                                                           blk);
 964
 965                 group_blk += rfs->new_fs->super->s_blocks_per_group;
 966         }
 967
 968         /* Allocate the missing data structures */
 969         for (i = 0; i < max_groups; i++) {
 970                 if (ext2fs_inode_table_loc(fs, i) &&
 971                     ext2fs_inode_bitmap_loc(fs, i) &&
 972                     ext2fs_block_bitmap_loc(fs, i))
 973                         continue;
 974
 975                 retval = ext2fs_allocate_group_table(fs, i,
 976                                                      rfs->reserve_blocks);
 977                 if (retval)
 978                         goto errout;
 979
 980                 /*
 981                  * For those structures that have changed, we need to
 982                  * do bookkeepping.
 983                  */
 984                 if (ext2fs_block_bitmap_loc(old_fs, i) !=
 985                     (blk = ext2fs_block_bitmap_loc(fs, i))) {
 986                         ext2fs_block_alloc_stats2(fs, blk, +1);
 987                         if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
 988                             !ext2fs_test_block_bitmap2(meta_bmap, blk))
 989                                 ext2fs_mark_block_bitmap2(rfs->move_blocks,
 990                                                          blk);
 991                 }
 992                 if (ext2fs_inode_bitmap_loc(old_fs, i) !=
 993                     (blk = ext2fs_inode_bitmap_loc(fs, i))) {
 994                         ext2fs_block_alloc_stats2(fs, blk, +1);
 995                         if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
 996                             !ext2fs_test_block_bitmap2(meta_bmap, blk))
 997                                 ext2fs_mark_block_bitmap2(rfs->move_blocks,
 998                                                          blk);
 999                 }
1000
1001                 /*
1002                  * The inode table, if we need to relocate it, is
1003                  * handled specially.  We have to reserve the blocks
1004                  * for both the old and the new inode table, since we
1005                  * can't have the inode table be destroyed during the
1006                  * block relocation phase.
1007                  */
1008                 if (ext2fs_inode_table_loc(fs, i) == ext2fs_inode_table_loc(old_fs, i))
1009                         continue;       /* inode table not moved */
1010
1011                 rfs->needed_blocks += fs->inode_blocks_per_group;
1012
1013                 /*
1014                  * Mark the new inode table as in use in the new block
1015                  * allocation bitmap, and move any blocks that might
1016                  * be necessary.
1017                  */
1018                 for (blk = ext2fs_inode_table_loc(fs, i), j=0;
1019                      j < fs->inode_blocks_per_group ; j++, blk++) {
1020                         ext2fs_block_alloc_stats2(fs, blk, +1);
1021                         if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
1022                             !ext2fs_test_block_bitmap2(meta_bmap, blk))
1023                                 ext2fs_mark_block_bitmap2(rfs->move_blocks,
1024                                                          blk);
1025                 }
1026
1027                 /*
1028                  * Make sure the old inode table is reserved in the
1029                  * block reservation bitmap.
1030                  */
1031                 for (blk = ext2fs_inode_table_loc(rfs->old_fs, i), j=0;
1032                      j < fs->inode_blocks_per_group ; j++, blk++)
1033                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
1034         }
1035         retval = 0;
1036
1037 errout:
1038         if (meta_bmap)
1039                 ext2fs_free_block_bitmap(meta_bmap);
1040
1041         return retval;
1042 }
1043
1044 /*
1045  * This helper function tries to allocate a new block.  We try to
1046  * avoid hitting the original group descriptor blocks at least at
1047  * first, since we want to make it possible to recover from a badly
1048  * aborted resize operation as much as possible.
1049  *
1050  * In the future, I may further modify this routine to balance out
1051  * where we get the new blocks across the various block groups.
1052  * Ideally we would allocate blocks that corresponded with the block
1053  * group of the containing inode, and keep contiguous blocks
1054  * together.  However, this very difficult to do efficiently, since we
1055  * don't have the necessary information up front.
1056  */
1057
1058 #define AVOID_OLD       1
1059 #define DESPERATION     2
1060
1061 static void init_block_alloc(ext2_resize_t rfs)
1062 {
1063         rfs->alloc_state = AVOID_OLD;
1064         rfs->new_blk = rfs->new_fs->super->s_first_data_block;
1065 #if 0
1066         /* HACK for testing */
1067         if (ext2fs_blocks_count(rfs->new_fs->super) >
1068             ext2fs_blocks_count(rfs->old_fs->super))
1069                 rfs->new_blk = ext2fs_blocks_count(rfs->old_fs->super);
1070 #endif
1071 }
1072
1073 static blk64_t get_new_block(ext2_resize_t rfs)
1074 {
1075         ext2_filsys     fs = rfs->new_fs;
1076
1077         while (1) {
1078                 if (rfs->new_blk >= ext2fs_blocks_count(fs->super)) {
1079                         if (rfs->alloc_state == DESPERATION)
1080                                 return 0;
1081
1082 #ifdef RESIZE2FS_DEBUG
1083                         if (rfs->flags & RESIZE_DEBUG_BMOVE)
1084                                 printf("Going into desperation mode "
1085                                        "for block allocations\n");
1086 #endif
1087                         rfs->alloc_state = DESPERATION;
1088                         rfs->new_blk = fs->super->s_first_data_block;
1089                         continue;
1090                 }
1091                 if (ext2fs_test_block_bitmap2(fs->block_map, rfs->new_blk) ||
1092                     ext2fs_test_block_bitmap2(rfs->reserve_blocks,
1093                                              rfs->new_blk) ||
1094                     ((rfs->alloc_state == AVOID_OLD) &&
1095                      (rfs->new_blk < ext2fs_blocks_count(rfs->old_fs->super)) &&
1096                      ext2fs_test_block_bitmap2(rfs->old_fs->block_map,
1097                                               rfs->new_blk))) {
1098                         rfs->new_blk++;
1099                         continue;
1100                 }
1101                 return rfs->new_blk;
1102         }
1103 }
1104
1105 static errcode_t resize2fs_get_alloc_block(ext2_filsys fs, blk64_t goal,
1106                                            blk64_t *ret)
1107 {
1108         ext2_resize_t rfs = (ext2_resize_t) fs->priv_data;
1109         blk64_t blk;
1110
1111         blk = get_new_block(rfs);
1112         if (!blk)
1113                 return ENOSPC;
1114
1115 #ifdef RESIZE2FS_DEBUG
1116         if (rfs->flags & 0xF)
1117                 printf("get_alloc_block allocating %llu\n", blk);
1118 #endif
1119
1120         ext2fs_mark_block_bitmap2(rfs->old_fs->block_map, blk);
1121         ext2fs_mark_block_bitmap2(rfs->new_fs->block_map, blk);
1122         *ret = (blk64_t) blk;
1123         return 0;
1124 }
1125
1126 static errcode_t block_mover(ext2_resize_t rfs)
1127 {
1128         blk64_t                 blk, old_blk, new_blk;
1129         ext2_filsys             fs = rfs->new_fs;
1130         ext2_filsys             old_fs = rfs->old_fs;
1131         errcode_t               retval;
1132         __u64                   size;
1133         int                     c;
1134         int                     to_move, moved;
1135         ext2_badblocks_list     badblock_list = 0;
1136         int                     bb_modified = 0;
1137
1138         fs->get_alloc_block = resize2fs_get_alloc_block;
1139         old_fs->get_alloc_block = resize2fs_get_alloc_block;
1140
1141         retval = ext2fs_read_bb_inode(old_fs, &badblock_list);
1142         if (retval)
1143                 return retval;
1144
1145         new_blk = fs->super->s_first_data_block;
1146         if (!rfs->itable_buf) {
1147                 retval = ext2fs_get_array(fs->blocksize,
1148                                         fs->inode_blocks_per_group,
1149                                         &rfs->itable_buf);
1150                 if (retval)
1151                         return retval;
1152         }
1153         retval = ext2fs_create_extent_table(&rfs->bmap, 0);
1154         if (retval)
1155                 return retval;
1156
1157         /*
1158          * The first step is to figure out where all of the blocks
1159          * will go.
1160          */
1161         to_move = moved = 0;
1162         init_block_alloc(rfs);
1163         for (blk = old_fs->super->s_first_data_block;
1164              blk < ext2fs_blocks_count(old_fs->super); blk++) {
1165                 if (!ext2fs_test_block_bitmap2(old_fs->block_map, blk))
1166                         continue;
1167                 if (!ext2fs_test_block_bitmap2(rfs->move_blocks, blk))
1168                         continue;
1169                 if (ext2fs_badblocks_list_test(badblock_list, blk)) {
1170                         ext2fs_badblocks_list_del(badblock_list, blk);
1171                         bb_modified++;
1172                         continue;
1173                 }
1174
1175                 new_blk = get_new_block(rfs);
1176                 if (!new_blk) {
1177                         retval = ENOSPC;
1178                         goto errout;
1179                 }
1180                 ext2fs_block_alloc_stats2(fs, new_blk, +1);
1181                 ext2fs_add_extent_entry(rfs->bmap, blk, new_blk);
1182                 to_move++;
1183         }
1184
1185         if (to_move == 0) {
1186                 if (rfs->bmap) {
1187                         ext2fs_free_extent_table(rfs->bmap);
1188                         rfs->bmap = 0;
1189                 }
1190                 retval = 0;
1191                 goto errout;
1192         }
1193
1194         /*
1195          * Step two is to actually move the blocks
1196          */
1197         retval =  ext2fs_iterate_extent(rfs->bmap, 0, 0, 0);
1198         if (retval) goto errout;
1199
1200         if (rfs->progress) {
1201                 retval = (rfs->progress)(rfs, E2_RSZ_BLOCK_RELOC_PASS,
1202                                          0, to_move);
1203                 if (retval)
1204                         goto errout;
1205         }
1206         while (1) {
1207                 retval = ext2fs_iterate_extent(rfs->bmap, &old_blk, &new_blk, &size);
1208                 if (retval) goto errout;
1209                 if (!size)
1210                         break;
1211 #ifdef RESIZE2FS_DEBUG
1212                 if (rfs->flags & RESIZE_DEBUG_BMOVE)
1213                         printf("Moving %llu blocks %llu->%llu\n",
1214                                size, old_blk, new_blk);
1215 #endif
1216                 do {
1217                         c = size;
1218                         if (c > fs->inode_blocks_per_group)
1219                                 c = fs->inode_blocks_per_group;
1220                         retval = io_channel_read_blk64(fs->io, old_blk, c,
1221                                                        rfs->itable_buf);
1222                         if (retval) goto errout;
1223                         retval = io_channel_write_blk64(fs->io, new_blk, c,
1224                                                         rfs->itable_buf);
1225                         if (retval) goto errout;
1226                         size -= c;
1227                         new_blk += c;
1228                         old_blk += c;
1229                         moved += c;
1230                         if (rfs->progress) {
1231                                 io_channel_flush(fs->io);
1232                                 retval = (rfs->progress)(rfs,
1233                                                 E2_RSZ_BLOCK_RELOC_PASS,
1234                                                 moved, to_move);
1235                                 if (retval)
1236                                         goto errout;
1237                         }
1238                 } while (size > 0);
1239                 io_channel_flush(fs->io);
1240         }
1241
1242 errout:
1243         if (badblock_list) {
1244                 if (!retval && bb_modified)
1245                         retval = ext2fs_update_bb_inode(old_fs,
1246                                                         badblock_list);
1247                 ext2fs_badblocks_list_free(badblock_list);
1248         }
1249         return retval;
1250 }
1251
1252
1253 /* --------------------------------------------------------------------
1254  *
1255  * Resize processing, phase 3
1256  *
1257  * --------------------------------------------------------------------
1258  */
1259
1260
1261 struct process_block_struct {
1262         ext2_resize_t           rfs;
1263         ext2_ino_t              ino;
1264         struct ext2_inode *     inode;
1265         errcode_t               error;
1266         int                     is_dir;
1267         int                     changed;
1268 };
1269
1270 static int process_block(ext2_filsys fs, blk64_t        *block_nr,
1271                          e2_blkcnt_t blockcnt,
1272                          blk64_t ref_block EXT2FS_ATTR((unused)),
1273                          int ref_offset EXT2FS_ATTR((unused)), void *priv_data)
1274 {
1275         struct process_block_struct *pb;
1276         errcode_t       retval;
1277         blk64_t         block, new_block;
1278         int             ret = 0;
1279
1280         pb = (struct process_block_struct *) priv_data;
1281         block = *block_nr;
1282         if (pb->rfs->bmap) {
1283                 new_block = ext2fs_extent_translate(pb->rfs->bmap, block);
1284                 if (new_block) {
1285                         *block_nr = new_block;
1286                         ret |= BLOCK_CHANGED;
1287                         pb->changed = 1;
1288 #ifdef RESIZE2FS_DEBUG
1289                         if (pb->rfs->flags & RESIZE_DEBUG_BMOVE)
1290                                 printf("ino=%u, blockcnt=%lld, %llu->%llu\n",
1291                                        pb->ino, blockcnt, block, new_block);
1292 #endif
1293                         block = new_block;
1294                 }
1295         }
1296         if (pb->is_dir) {
1297                 retval = ext2fs_add_dir_block2(fs->dblist, pb->ino,
1298                                                block, (int) blockcnt);
1299                 if (retval) {
1300                         pb->error = retval;
1301                         ret |= BLOCK_ABORT;
1302                 }
1303         }
1304         return ret;
1305 }
1306
1307 /*
1308  * Progress callback
1309  */
1310 static errcode_t progress_callback(ext2_filsys fs,
1311                                    ext2_inode_scan scan EXT2FS_ATTR((unused)),
1312                                    dgrp_t group, void * priv_data)
1313 {
1314         ext2_resize_t rfs = (ext2_resize_t) priv_data;
1315         errcode_t               retval;
1316
1317         /*
1318          * This check is to protect against old ext2 libraries.  It
1319          * shouldn't be needed against new libraries.
1320          */
1321         if ((group+1) == 0)
1322                 return 0;
1323
1324         if (rfs->progress) {
1325                 io_channel_flush(fs->io);
1326                 retval = (rfs->progress)(rfs, E2_RSZ_INODE_SCAN_PASS,
1327                                          group+1, fs->group_desc_count);
1328                 if (retval)
1329                         return retval;
1330         }
1331
1332         return 0;
1333 }
1334
1335 static errcode_t inode_scan_and_fix(ext2_resize_t rfs)
1336 {
1337         struct process_block_struct     pb;
1338         ext2_ino_t              ino, new_inode;
1339         struct ext2_inode       *inode = NULL;
1340         ext2_inode_scan         scan = NULL;
1341         errcode_t               retval;
1342         char                    *block_buf = 0;
1343         ext2_ino_t              start_to_move;
1344         blk64_t                 orig_size;
1345         blk64_t                 new_block;
1346         int                     inode_size;
1347
1348         if ((rfs->old_fs->group_desc_count <=
1349              rfs->new_fs->group_desc_count) &&
1350             !rfs->bmap)
1351                 return 0;
1352
1353         /*
1354          * Save the original size of the old filesystem, and
1355          * temporarily set the size to be the new size if the new size
1356          * is larger.  We need to do this to avoid catching an error
1357          * by the block iterator routines
1358          */
1359         orig_size = ext2fs_blocks_count(rfs->old_fs->super);
1360         if (orig_size < ext2fs_blocks_count(rfs->new_fs->super))
1361                 ext2fs_blocks_count_set(rfs->old_fs->super,
1362                                 ext2fs_blocks_count(rfs->new_fs->super));
1363
1364         retval = ext2fs_open_inode_scan(rfs->old_fs, 0, &scan);
1365         if (retval) goto errout;
1366
1367         retval = ext2fs_init_dblist(rfs->old_fs, 0);
1368         if (retval) goto errout;
1369         retval = ext2fs_get_array(rfs->old_fs->blocksize, 3, &block_buf);
1370         if (retval) goto errout;
1371
1372         start_to_move = (rfs->new_fs->group_desc_count *
1373                          rfs->new_fs->super->s_inodes_per_group);
1374
1375         if (rfs->progress) {
1376                 retval = (rfs->progress)(rfs, E2_RSZ_INODE_SCAN_PASS,
1377                                          0, rfs->old_fs->group_desc_count);
1378                 if (retval)
1379                         goto errout;
1380         }
1381         ext2fs_set_inode_callback(scan, progress_callback, (void *) rfs);
1382         pb.rfs = rfs;
1383         pb.inode = inode;
1384         pb.error = 0;
1385         new_inode = EXT2_FIRST_INODE(rfs->new_fs->super);
1386         inode_size = EXT2_INODE_SIZE(rfs->new_fs->super);
1387         inode = malloc(inode_size);
1388         if (!inode) {
1389                 retval = ENOMEM;
1390                 goto errout;
1391         }
1392         /*
1393          * First, copy all of the inodes that need to be moved
1394          * elsewhere in the inode table
1395          */
1396         while (1) {
1397                 retval = ext2fs_get_next_inode_full(scan, &ino, inode, inode_size);
1398                 if (retval) goto errout;
1399                 if (!ino)
1400                         break;
1401
1402                 if (inode->i_links_count == 0 && ino != EXT2_RESIZE_INO)
1403                         continue; /* inode not in use */
1404
1405                 pb.is_dir = LINUX_S_ISDIR(inode->i_mode);
1406                 pb.changed = 0;
1407
1408                 if (ext2fs_file_acl_block(rfs->old_fs, inode) && rfs->bmap) {
1409                         new_block = ext2fs_extent_translate(rfs->bmap,
1410                                 ext2fs_file_acl_block(rfs->old_fs, inode));
1411                         if (new_block) {
1412                                 ext2fs_file_acl_block_set(rfs->old_fs, inode,
1413                                                           new_block);
1414                                 retval = ext2fs_write_inode_full(rfs->old_fs,
1415                                                             ino, inode, inode_size);
1416                                 if (retval) goto errout;
1417                         }
1418                 }
1419
1420                 if (ext2fs_inode_has_valid_blocks2(rfs->old_fs, inode) &&
1421                     (rfs->bmap || pb.is_dir)) {
1422                         pb.ino = ino;
1423                         retval = ext2fs_block_iterate3(rfs->old_fs,
1424                                                        ino, 0, block_buf,
1425                                                        process_block, &pb);
1426                         if (retval)
1427                                 goto errout;
1428                         if (pb.error) {
1429                                 retval = pb.error;
1430                                 goto errout;
1431                         }
1432                 }
1433
1434                 if (ino <= start_to_move)
1435                         continue; /* Don't need to move it. */
1436
1437                 /*
1438                  * Find a new inode
1439                  */
1440                 retval = ext2fs_new_inode(rfs->new_fs, 0, 0, 0, &new_inode);
1441                 if (retval)
1442                         goto errout;
1443
1444                 ext2fs_inode_alloc_stats2(rfs->new_fs, new_inode, +1,
1445                                           pb.is_dir);
1446                 if (pb.changed) {
1447                         /* Get the new version of the inode */
1448                         retval = ext2fs_read_inode_full(rfs->old_fs, ino,
1449                                                 inode, inode_size);
1450                         if (retval) goto errout;
1451                 }
1452                 inode->i_ctime = time(0);
1453                 retval = ext2fs_write_inode_full(rfs->old_fs, new_inode,
1454                                                 inode, inode_size);
1455                 if (retval) goto errout;
1456
1457 #ifdef RESIZE2FS_DEBUG
1458                 if (rfs->flags & RESIZE_DEBUG_INODEMAP)
1459                         printf("Inode moved %u->%u\n", ino, new_inode);
1460 #endif
1461                 if (!rfs->imap) {
1462                         retval = ext2fs_create_extent_table(&rfs->imap, 0);
1463                         if (retval)
1464                                 goto errout;
1465                 }
1466                 ext2fs_add_extent_entry(rfs->imap, ino, new_inode);
1467         }
1468         io_channel_flush(rfs->old_fs->io);
1469
1470 errout:
1471         ext2fs_blocks_count_set(rfs->old_fs->super, orig_size);
1472         if (rfs->bmap) {
1473                 ext2fs_free_extent_table(rfs->bmap);
1474                 rfs->bmap = 0;
1475         }
1476         if (scan)
1477                 ext2fs_close_inode_scan(scan);
1478         if (block_buf)
1479                 ext2fs_free_mem(&block_buf);
1480         free(inode);
1481         return retval;
1482 }
1483
1484 /* --------------------------------------------------------------------
1485  *
1486  * Resize processing, phase 4.
1487  *
1488  * --------------------------------------------------------------------
1489  */
1490
1491 struct istruct {
1492         ext2_resize_t rfs;
1493         errcode_t       err;
1494         unsigned int    max_dirs;
1495         unsigned int    num;
1496 };
1497
1498 static int check_and_change_inodes(ext2_ino_t dir,
1499                                    int entry EXT2FS_ATTR((unused)),
1500                                    struct ext2_dir_entry *dirent, int offset,
1501                                    int  blocksize EXT2FS_ATTR((unused)),
1502                                    char *buf EXT2FS_ATTR((unused)),
1503                                    void *priv_data)
1504 {
1505         struct istruct *is = (struct istruct *) priv_data;
1506         struct ext2_inode       inode;
1507         ext2_ino_t              new_inode;
1508         errcode_t               retval;
1509
1510         if (is->rfs->progress && offset == 0) {
1511                 io_channel_flush(is->rfs->old_fs->io);
1512                 is->err = (is->rfs->progress)(is->rfs,
1513                                               E2_RSZ_INODE_REF_UPD_PASS,
1514                                               ++is->num, is->max_dirs);
1515                 if (is->err)
1516                         return DIRENT_ABORT;
1517         }
1518
1519         if (!dirent->inode)
1520                 return 0;
1521
1522         new_inode = ext2fs_extent_translate(is->rfs->imap, dirent->inode);
1523
1524         if (!new_inode)
1525                 return 0;
1526 #ifdef RESIZE2FS_DEBUG
1527         if (is->rfs->flags & RESIZE_DEBUG_INODEMAP)
1528                 printf("Inode translate (dir=%u, name=%.*s, %u->%u)\n",
1529                        dir, dirent->name_len&0xFF, dirent->name,
1530                        dirent->inode, new_inode);
1531 #endif
1532
1533         dirent->inode = new_inode;
1534
1535         /* Update the directory mtime and ctime */
1536         retval = ext2fs_read_inode(is->rfs->old_fs, dir, &inode);
1537         if (retval == 0) {
1538                 inode.i_mtime = inode.i_ctime = time(0);
1539                 is->err = ext2fs_write_inode(is->rfs->old_fs, dir, &inode);
1540                 if (is->err)
1541                         return DIRENT_ABORT;
1542         }
1543
1544         return DIRENT_CHANGED;
1545 }
1546
1547 static errcode_t inode_ref_fix(ext2_resize_t rfs)
1548 {
1549         errcode_t               retval;
1550         struct istruct          is;
1551
1552         if (!rfs->imap)
1553                 return 0;
1554
1555         /*
1556          * Now, we iterate over all of the directories to update the
1557          * inode references
1558          */
1559         is.num = 0;
1560         is.max_dirs = ext2fs_dblist_count2(rfs->old_fs->dblist);
1561         is.rfs = rfs;
1562         is.err = 0;
1563
1564         if (rfs->progress) {
1565                 retval = (rfs->progress)(rfs, E2_RSZ_INODE_REF_UPD_PASS,
1566                                          0, is.max_dirs);
1567                 if (retval)
1568                         goto errout;
1569         }
1570
1571         retval = ext2fs_dblist_dir_iterate(rfs->old_fs->dblist,
1572                                            DIRENT_FLAG_INCLUDE_EMPTY, 0,
1573                                            check_and_change_inodes, &is);
1574         if (retval)
1575                 goto errout;
1576         if (is.err) {
1577                 retval = is.err;
1578                 goto errout;
1579         }
1580
1581         if (rfs->progress && (is.num < is.max_dirs))
1582                 (rfs->progress)(rfs, E2_RSZ_INODE_REF_UPD_PASS,
1583                                 is.max_dirs, is.max_dirs);
1584
1585 errout:
1586         ext2fs_free_extent_table(rfs->imap);
1587         rfs->imap = 0;
1588         return retval;
1589 }
1590
1591
1592 /* --------------------------------------------------------------------
1593  *
1594  * Resize processing, phase 5.
1595  *
1596  * In this phase we actually move the inode table around, and then
1597  * update the summary statistics.  This is scary, since aborting here
1598  * will potentially scramble the filesystem.  (We are moving the
1599  * inode tables around in place, and so the potential for lost data,
1600  * or at the very least scrambling the mapping between filenames and
1601  * inode numbers is very high in case of a power failure here.)
1602  * --------------------------------------------------------------------
1603  */
1604
1605
1606 /*
1607  * A very scary routine --- this one moves the inode table around!!!
1608  *
1609  * After this you have to use the rfs->new_fs file handle to read and
1610  * write inodes.
1611  */
1612 static errcode_t move_itables(ext2_resize_t rfs)
1613 {
1614         int             n, num, size;
1615         long long       diff;
1616         dgrp_t          i, max_groups;
1617         ext2_filsys     fs = rfs->new_fs;
1618         char            *cp;
1619         blk64_t         old_blk, new_blk, blk;
1620         errcode_t       retval;
1621         int             j, to_move, moved;
1622
1623         max_groups = fs->group_desc_count;
1624         if (max_groups > rfs->old_fs->group_desc_count)
1625                 max_groups = rfs->old_fs->group_desc_count;
1626
1627         size = fs->blocksize * fs->inode_blocks_per_group;
1628         if (!rfs->itable_buf) {
1629                 retval = ext2fs_get_mem(size, &rfs->itable_buf);
1630                 if (retval)
1631                         return retval;
1632         }
1633
1634         /*
1635          * Figure out how many inode tables we need to move
1636          */
1637         to_move = moved = 0;
1638         for (i=0; i < max_groups; i++)
1639                 if (ext2fs_inode_table_loc(rfs->old_fs, i) !=
1640                     ext2fs_inode_table_loc(fs, i))
1641                         to_move++;
1642
1643         if (to_move == 0)
1644                 return 0;
1645
1646         if (rfs->progress) {
1647                 retval = rfs->progress(rfs, E2_RSZ_MOVE_ITABLE_PASS,
1648                                        0, to_move);
1649                 if (retval)
1650                         goto errout;
1651         }
1652
1653         rfs->old_fs->flags |= EXT2_FLAG_MASTER_SB_ONLY;
1654
1655         for (i=0; i < max_groups; i++) {
1656                 old_blk = ext2fs_inode_table_loc(rfs->old_fs, i);
1657                 new_blk = ext2fs_inode_table_loc(fs, i);
1658                 diff = new_blk - old_blk;
1659
1660 #ifdef RESIZE2FS_DEBUG
1661                 if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
1662                         printf("Itable move group %d block %llu->%llu (diff %lld)\n",
1663                                i, old_blk, new_blk, diff);
1664 #endif
1665
1666                 if (!diff)
1667                         continue;
1668
1669                 retval = io_channel_read_blk64(fs->io, old_blk,
1670                                                fs->inode_blocks_per_group,
1671                                                rfs->itable_buf);
1672                 if (retval)
1673                         goto errout;
1674                 /*
1675                  * The end of the inode table segment often contains
1676                  * all zeros, and we're often only moving the inode
1677                  * table down a block or two.  If so, we can optimize
1678                  * things by not rewriting blocks that we know to be zero
1679                  * already.
1680                  */
1681                 for (cp = rfs->itable_buf+size-1, n=0; n < size; n++, cp--)
1682                         if (*cp)
1683                                 break;
1684                 n = n >> EXT2_BLOCK_SIZE_BITS(fs->super);
1685 #ifdef RESIZE2FS_DEBUG
1686                 if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
1687                         printf("%d blocks of zeros...\n", n);
1688 #endif
1689                 num = fs->inode_blocks_per_group;
1690                 if (n > diff)
1691                         num -= n;
1692
1693                 retval = io_channel_write_blk64(fs->io, new_blk,
1694                                                 num, rfs->itable_buf);
1695                 if (retval) {
1696                         io_channel_write_blk64(fs->io, old_blk,
1697                                                num, rfs->itable_buf);
1698                         goto errout;
1699                 }
1700                 if (n > diff) {
1701                         retval = io_channel_write_blk64(fs->io,
1702                               old_blk + fs->inode_blocks_per_group,
1703                               diff, (rfs->itable_buf +
1704                                      (fs->inode_blocks_per_group - diff) *
1705                                      fs->blocksize));
1706                         if (retval)
1707                                 goto errout;
1708                 }
1709
1710                 for (blk = ext2fs_inode_table_loc(rfs->old_fs, i), j=0;
1711                      j < fs->inode_blocks_per_group ; j++, blk++)
1712                         ext2fs_block_alloc_stats2(fs, blk, -1);
1713
1714                 ext2fs_inode_table_loc_set(rfs->old_fs, i, new_blk);
1715                 ext2fs_group_desc_csum_set(rfs->old_fs, i);
1716                 ext2fs_mark_super_dirty(rfs->old_fs);
1717                 ext2fs_flush(rfs->old_fs);
1718
1719                 if (rfs->progress) {
1720                         retval = rfs->progress(rfs, E2_RSZ_MOVE_ITABLE_PASS,
1721                                                ++moved, to_move);
1722                         if (retval)
1723                                 goto errout;
1724                 }
1725         }
1726         mark_table_blocks(fs, fs->block_map);
1727         ext2fs_flush(fs);
1728 #ifdef RESIZE2FS_DEBUG
1729         if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
1730                 printf("Inode table move finished.\n");
1731 #endif
1732         return 0;
1733
1734 errout:
1735         return retval;
1736 }
1737
1738 /*
1739  * Fix the resize inode
1740  */
1741 static errcode_t fix_resize_inode(ext2_filsys fs)
1742 {
1743         struct ext2_inode       inode;
1744         errcode_t               retval;
1745         char                    *block_buf = NULL;
1746
1747         if (!(fs->super->s_feature_compat &
1748               EXT2_FEATURE_COMPAT_RESIZE_INODE))
1749                 return 0;
1750
1751         retval = ext2fs_get_mem(fs->blocksize, &block_buf);
1752         if (retval) goto errout;
1753
1754         retval = ext2fs_read_inode(fs, EXT2_RESIZE_INO, &inode);
1755         if (retval) goto errout;
1756
1757         ext2fs_iblk_set(fs, &inode, 1);
1758
1759         retval = ext2fs_write_inode(fs, EXT2_RESIZE_INO, &inode);
1760         if (retval) goto errout;
1761
1762         if (!inode.i_block[EXT2_DIND_BLOCK]) {
1763                 /*
1764                  * Avoid zeroing out block #0; that's rude.  This
1765                  * should never happen anyway since the filesystem
1766                  * should be fsck'ed and we assume it is consistent.
1767                  */
1768                 fprintf(stderr,
1769                         _("Should never happen: resize inode corrupt!\n"));
1770                 exit(1);
1771         }
1772
1773         memset(block_buf, 0, fs->blocksize);
1774
1775         retval = io_channel_write_blk64(fs->io, inode.i_block[EXT2_DIND_BLOCK],
1776                                         1, block_buf);
1777         if (retval) goto errout;
1778
1779         retval = ext2fs_create_resize_inode(fs);
1780         if (retval)
1781                 goto errout;
1782
1783 errout:
1784         if (block_buf)
1785                 ext2fs_free_mem(&block_buf);
1786         return retval;
1787 }
1788
1789 /*
1790  * Finally, recalculate the summary information
1791  */
1792 static errcode_t ext2fs_calculate_summary_stats(ext2_filsys fs)
1793 {
1794         blk64_t         blk;
1795         ext2_ino_t      ino;
1796         unsigned int    group = 0;
1797         unsigned int    count = 0;
1798         int             total_free = 0;
1799         int             group_free = 0;
1800         int             uninit = 0;
1801         blk64_t         super_blk, old_desc_blk, new_desc_blk;
1802         int             old_desc_blocks;
1803
1804         /*
1805          * First calculate the block statistics
1806          */
1807         uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_BLOCK_UNINIT);
1808         ext2fs_super_and_bgd_loc2(fs, group, &super_blk, &old_desc_blk,
1809                                   &new_desc_blk, 0);
1810         if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
1811                 old_desc_blocks = fs->super->s_first_meta_bg;
1812         else
1813                 old_desc_blocks = fs->desc_blocks +
1814                         fs->super->s_reserved_gdt_blocks;
1815         for (blk = fs->super->s_first_data_block;
1816              blk < ext2fs_blocks_count(fs->super); blk++) {
1817                 if ((uninit &&
1818                      !((blk == super_blk) ||
1819                        ((old_desc_blk && old_desc_blocks &&
1820                          (blk >= old_desc_blk) &&
1821                          (blk < old_desc_blk + old_desc_blocks))) ||
1822                        ((new_desc_blk && (blk == new_desc_blk))) ||
1823                        (blk == ext2fs_block_bitmap_loc(fs, group)) ||
1824                        (blk == ext2fs_inode_bitmap_loc(fs, group)) ||
1825                        ((blk >= ext2fs_inode_table_loc(fs, group) &&
1826                          (blk < ext2fs_inode_table_loc(fs, group)
1827                           + fs->inode_blocks_per_group))))) ||
1828                     (!ext2fs_fast_test_block_bitmap2(fs->block_map, blk))) {
1829                         group_free++;
1830                         total_free++;
1831                 }
1832                 count++;
1833                 if ((count == fs->super->s_blocks_per_group) ||
1834                     (blk == ext2fs_blocks_count(fs->super)-1)) {
1835                         ext2fs_bg_free_blocks_count_set(fs, group, group_free);
1836                         ext2fs_group_desc_csum_set(fs, group);
1837                         group++;
1838                         if (group >= fs->group_desc_count)
1839                                 break;
1840                         count = 0;
1841                         group_free = 0;
1842                         uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_BLOCK_UNINIT);
1843                         ext2fs_super_and_bgd_loc2(fs, group, &super_blk,
1844                                                   &old_desc_blk,
1845                                                   &new_desc_blk, 0);
1846                         if (fs->super->s_feature_incompat &
1847                             EXT2_FEATURE_INCOMPAT_META_BG)
1848                                 old_desc_blocks = fs->super->s_first_meta_bg;
1849                         else
1850                                 old_desc_blocks = fs->desc_blocks +
1851                                         fs->super->s_reserved_gdt_blocks;
1852                 }
1853         }
1854         ext2fs_free_blocks_count_set(fs->super, total_free);
1855
1856         /*
1857          * Next, calculate the inode statistics
1858          */
1859         group_free = 0;
1860         total_free = 0;
1861         count = 0;
1862         group = 0;
1863
1864         /* Protect loop from wrap-around if s_inodes_count maxed */
1865         uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_INODE_UNINIT);
1866         for (ino = 1; ino <= fs->super->s_inodes_count && ino > 0; ino++) {
1867                 if (uninit ||
1868                     !ext2fs_fast_test_inode_bitmap2(fs->inode_map, ino)) {
1869                         group_free++;
1870                         total_free++;
1871                 }
1872                 count++;
1873                 if ((count == fs->super->s_inodes_per_group) ||
1874                     (ino == fs->super->s_inodes_count)) {
1875                         ext2fs_bg_free_inodes_count_set(fs, group, group_free);
1876                         ext2fs_group_desc_csum_set(fs, group);
1877                         group++;
1878                         if (group >= fs->group_desc_count)
1879                                 break;
1880                         count = 0;
1881                         group_free = 0;
1882                         uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_INODE_UNINIT);
1883                 }
1884         }
1885         fs->super->s_free_inodes_count = total_free;
1886         ext2fs_mark_super_dirty(fs);
1887         return 0;
1888 }
1889
1890 /*
1891  *  Journal may have been relocated; update the backup journal blocks
1892  *  in the superblock.
1893  */
1894 static errcode_t fix_sb_journal_backup(ext2_filsys fs)
1895 {
1896         errcode_t         retval;
1897         struct ext2_inode inode;
1898
1899         if (!(fs->super->s_feature_compat & EXT3_FEATURE_COMPAT_HAS_JOURNAL))
1900                 return 0;
1901
1902         /* External journal? Nothing to do. */
1903         if (fs->super->s_journal_dev && !fs->super->s_journal_inum)
1904                 return 0;
1905
1906         retval = ext2fs_read_inode(fs, fs->super->s_journal_inum, &inode);
1907         if (retval)
1908                 return retval;
1909         memcpy(fs->super->s_jnl_blocks, inode.i_block, EXT2_N_BLOCKS*4);
1910         fs->super->s_jnl_blocks[15] = inode.i_size_high;
1911         fs->super->s_jnl_blocks[16] = inode.i_size;
1912         fs->super->s_jnl_backup_type = EXT3_JNL_BACKUP_BLOCKS;
1913         ext2fs_mark_super_dirty(fs);
1914         return 0;
1915 }
1916
1917 static int calc_group_overhead(ext2_filsys fs, blk64_t grp,
1918                                int old_desc_blocks)
1919 {
1920         blk64_t super_blk, old_desc_blk, new_desc_blk;
1921         int overhead;
1922
1923         /* inode table blocks plus allocation bitmaps */
1924         overhead = fs->inode_blocks_per_group + 2;
1925
1926         ext2fs_super_and_bgd_loc2(fs, grp, &super_blk,
1927                                   &old_desc_blk, &new_desc_blk, 0);
1928         if ((grp == 0) || super_blk)
1929                 overhead++;
1930         if (old_desc_blk)
1931                 overhead += old_desc_blocks;
1932         else if (new_desc_blk)
1933                 overhead++;
1934         return overhead;
1935 }
1936
1937
1938 /*
1939  * calcluate the minimum number of blocks the given fs can be resized to
1940  */
1941 blk64_t calculate_minimum_resize_size(ext2_filsys fs)
1942 {
1943         ext2_ino_t inode_count;
1944         blk64_t blks_needed, groups, data_blocks;
1945         blk64_t grp, data_needed, last_start;
1946         blk64_t overhead = 0;
1947         int old_desc_blocks;
1948         int extra_groups = 0;
1949         int flexbg_size = 1 << fs->super->s_log_groups_per_flex;
1950
1951         /*
1952          * first figure out how many group descriptors we need to
1953          * handle the number of inodes we have
1954          */
1955         inode_count = fs->super->s_inodes_count -
1956                 fs->super->s_free_inodes_count;
1957         blks_needed = ext2fs_div_ceil(inode_count,
1958                                       fs->super->s_inodes_per_group) *
1959                 EXT2_BLOCKS_PER_GROUP(fs->super);
1960         groups = ext2fs_div64_ceil(blks_needed,
1961                                    EXT2_BLOCKS_PER_GROUP(fs->super));
1962
1963         /*
1964          * number of old-style block group descriptor blocks
1965          */
1966         if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
1967                 old_desc_blocks = fs->super->s_first_meta_bg;
1968         else
1969                 old_desc_blocks = fs->desc_blocks +
1970                         fs->super->s_reserved_gdt_blocks;
1971
1972         /* calculate how many blocks are needed for data */
1973         data_needed = ext2fs_blocks_count(fs->super) -
1974                 ext2fs_free_blocks_count(fs->super);
1975
1976         for (grp = 0; grp < fs->group_desc_count; grp++)
1977                 data_needed -= calc_group_overhead(fs, grp, old_desc_blocks);
1978
1979         /*
1980          * For ext4 we need to allow for up to a flex_bg worth of
1981          * inode tables of slack space so the resize operation can be
1982          * guaranteed to finish.
1983          */
1984         if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_FLEX_BG) {
1985                 extra_groups = flexbg_size - (groups & (flexbg_size - 1));
1986                 data_needed += fs->inode_blocks_per_group * extra_groups;
1987                 extra_groups = groups % flexbg_size;
1988         }
1989
1990         /*
1991          * figure out how many data blocks we have given the number of groups
1992          * we need for our inodes
1993          */
1994         data_blocks = groups * EXT2_BLOCKS_PER_GROUP(fs->super);
1995         last_start = 0;
1996         for (grp = 0; grp < groups; grp++) {
1997                 overhead = calc_group_overhead(fs, grp, old_desc_blocks);
1998
1999                 /*
2000                  * we want to keep track of how much data we can store in
2001                  * the groups leading up to the last group so we can determine
2002                  * how big the last group needs to be
2003                  */
2004                 if (grp != (groups - 1))
2005                         last_start += EXT2_BLOCKS_PER_GROUP(fs->super) -
2006                                 overhead;
2007
2008                 data_blocks -= overhead;
2009         }
2010
2011         /*
2012          * if we need more group descriptors in order to accomodate our data
2013          * then we need to add them here
2014          */
2015         while (data_needed > data_blocks) {
2016                 blk64_t remainder = data_needed - data_blocks;
2017                 blk64_t extra_grps;
2018
2019                 /* figure out how many more groups we need for the data */
2020                 extra_grps = ext2fs_div64_ceil(remainder,
2021                                                EXT2_BLOCKS_PER_GROUP(fs->super));
2022
2023                 data_blocks += extra_grps * EXT2_BLOCKS_PER_GROUP(fs->super);
2024
2025                 /* ok we have to account for the last group */
2026                 overhead = calc_group_overhead(fs, groups-1, old_desc_blocks);
2027                 last_start += EXT2_BLOCKS_PER_GROUP(fs->super) - overhead;
2028
2029                 for (grp = groups; grp < groups+extra_grps; grp++) {
2030                         overhead = calc_group_overhead(fs, grp,
2031                                                        old_desc_blocks);
2032
2033                         /*
2034                          * again, we need to see how much data we cram into
2035                          * all of the groups leading up to the last group
2036                          */
2037                         if (grp != (groups + extra_grps - 1))
2038                                 last_start += EXT2_BLOCKS_PER_GROUP(fs->super)
2039                                         - overhead;
2040
2041                         data_blocks -= overhead;
2042                 }
2043
2044                 groups += extra_grps;
2045                 extra_groups += extra_grps;
2046                 if (fs->super->s_feature_incompat
2047                         & EXT4_FEATURE_INCOMPAT_FLEX_BG
2048                     && extra_groups > flexbg_size) {
2049                         /*
2050                          * For ext4 we need to allow for up to a flex_bg worth
2051                          * of inode tables of slack space so the resize
2052                          * operation can be guaranteed to finish.
2053                          */
2054                         extra_groups = flexbg_size -
2055                                                 (groups & (flexbg_size - 1));
2056                         data_needed += (fs->inode_blocks_per_group *
2057                                         extra_groups);
2058                         extra_groups = groups % flexbg_size;
2059                 }
2060         }
2061
2062         /* now for the fun voodoo */
2063         overhead = calc_group_overhead(fs, groups-1, old_desc_blocks);
2064
2065         /*
2066          * if this is the case then the last group is going to have data in it
2067          * so we need to adjust the size of the last group accordingly
2068          */
2069         if (last_start < data_needed) {
2070                 blk64_t remainder = data_needed - last_start;
2071
2072                 /*
2073                  * 50 is a magic number that mkfs/resize uses to see if its
2074                  * even worth making/resizing the fs.  basically you need to
2075                  * have at least 50 blocks in addition to the blocks needed
2076                  * for the metadata in the last group
2077                  */
2078                 if (remainder > 50)
2079                         overhead += remainder;
2080                 else
2081                         overhead += 50;
2082         } else
2083                 overhead += 50;
2084
2085         overhead += fs->super->s_first_data_block;
2086
2087         /*
2088          * since our last group doesn't have to be BLOCKS_PER_GROUP large, we
2089          * only do groups-1, and then add the number of blocks needed to
2090          * handle the group descriptor metadata+data that we need
2091          */
2092         blks_needed = (groups-1) * EXT2_BLOCKS_PER_GROUP(fs->super);
2093         blks_needed += overhead;
2094
2095         /*
2096          * If at this point we've already added up more "needed" than
2097          * the current size, just return current size as minimum.
2098          */
2099         if (blks_needed >= ext2fs_blocks_count(fs->super))
2100                 return ext2fs_blocks_count(fs->super);
2101         /*
2102          * We need to reserve a few extra blocks if extents are
2103          * enabled, in case we need to grow the extent tree.  The more
2104          * we shrink the file system, the more space we need.
2105          */
2106         if (fs->super->s_feature_incompat & EXT3_FEATURE_INCOMPAT_EXTENTS)
2107                 blks_needed += (ext2fs_blocks_count(fs->super) -
2108                                 blks_needed)/500;
2109
2110         return blks_needed;
2111 }