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 static errcode_t mark_table_blocks(ext2_filsys fs,
  55                                    ext2fs_block_bitmap bmap);
  56
  57 /*
  58  * Some helper CPP macros
  59  */
  60 #define IS_BLOCK_BM(fs, i, blk) ((blk) == ext2fs_block_bitmap_loc((fs),(i)))
  61 #define IS_INODE_BM(fs, i, blk) ((blk) == ext2fs_inode_bitmap_loc((fs),(i)))
  62
  63 #define IS_INODE_TB(fs, i, blk) (((blk) >= ext2fs_inode_table_loc((fs), (i))) && \
  64                                  ((blk) < (ext2fs_inode_table_loc((fs), (i)) + \
  65                                            (fs)->inode_blocks_per_group)))
  66
  67 /* Some bigalloc helper macros which are more succint... */
  68 #define B2C(x)  EXT2FS_B2C(fs, (x))
  69 #define C2B(x)  EXT2FS_C2B(fs, (x))
  70 #define EQ_CLSTR(x, y) (B2C(x) == B2C(y))
  71 #define LE_CLSTR(x, y) (B2C(x) <= B2C(y))
  72 #define LT_CLSTR(x, y) (B2C(x) <  B2C(y))
  73 #define GE_CLSTR(x, y) (B2C(x) >= B2C(y))
  74 #define GT_CLSTR(x, y) (B2C(x) >  B2C(y))
  75
  76 int lazy_itable_init;
  77
  78 /*
  79  * This is the top-level routine which does the dirty deed....
  80  */
  81 errcode_t resize_fs(ext2_filsys fs, blk64_t *new_size, int flags,
  82             errcode_t (*progress)(ext2_resize_t rfs, int pass,
  83                                           unsigned long cur,
  84                                           unsigned long max_val))
  85 {
  86         ext2_resize_t   rfs;
  87         errcode_t       retval;
  88         struct resource_track   rtrack, overall_track;
  89
  90         /*
  91          * Create the data structure
  92          */
  93         retval = ext2fs_get_mem(sizeof(struct ext2_resize_struct), &rfs);
  94         if (retval)
  95                 return retval;
  96
  97         memset(rfs, 0, sizeof(struct ext2_resize_struct));
  98         fs->priv_data = rfs;
  99         rfs->old_fs = fs;
 100         rfs->flags = flags;
 101         rfs->itable_buf  = 0;
 102         rfs->progress = progress;
 103
 104         init_resource_track(&overall_track, "overall resize2fs", fs->io);
 105         init_resource_track(&rtrack, "read_bitmaps", fs->io);
 106         retval = ext2fs_read_bitmaps(fs);
 107         if (retval)
 108                 goto errout;
 109         print_resource_track(rfs, &rtrack, fs->io);
 110
 111         fs->super->s_state |= EXT2_ERROR_FS;
 112         ext2fs_mark_super_dirty(fs);
 113         ext2fs_flush(fs);
 114
 115         init_resource_track(&rtrack, "fix_uninit_block_bitmaps 1", fs->io);
 116         fix_uninit_block_bitmaps(fs);
 117         print_resource_track(rfs, &rtrack, fs->io);
 118         retval = ext2fs_dup_handle(fs, &rfs->new_fs);
 119         if (retval)
 120                 goto errout;
 121
 122         init_resource_track(&rtrack, "adjust_superblock", fs->io);
 123         retval = adjust_superblock(rfs, *new_size);
 124         if (retval)
 125                 goto errout;
 126         print_resource_track(rfs, &rtrack, fs->io);
 127
 128
 129         init_resource_track(&rtrack, "fix_uninit_block_bitmaps 2", fs->io);
 130         fix_uninit_block_bitmaps(rfs->new_fs);
 131         print_resource_track(rfs, &rtrack, fs->io);
 132         /* Clear the block bitmap uninit flag for the last block group */
 133         ext2fs_bg_flags_clear(rfs->new_fs, rfs->new_fs->group_desc_count - 1,
 134                              EXT2_BG_BLOCK_UNINIT);
 135
 136         *new_size = ext2fs_blocks_count(rfs->new_fs->super);
 137
 138         init_resource_track(&rtrack, "blocks_to_move", fs->io);
 139         retval = blocks_to_move(rfs);
 140         if (retval)
 141                 goto errout;
 142         print_resource_track(rfs, &rtrack, fs->io);
 143
 144 #ifdef RESIZE2FS_DEBUG
 145         if (rfs->flags & RESIZE_DEBUG_BMOVE)
 146                 printf("Number of free blocks: %llu/%llu, Needed: %llu\n",
 147                        ext2fs_free_blocks_count(rfs->old_fs->super),
 148                        ext2fs_free_blocks_count(rfs->new_fs->super),
 149                        rfs->needed_blocks);
 150 #endif
 151
 152         init_resource_track(&rtrack, "block_mover", fs->io);
 153         retval = block_mover(rfs);
 154         if (retval)
 155                 goto errout;
 156         print_resource_track(rfs, &rtrack, fs->io);
 157
 158         init_resource_track(&rtrack, "inode_scan_and_fix", fs->io);
 159         retval = inode_scan_and_fix(rfs);
 160         if (retval)
 161                 goto errout;
 162         print_resource_track(rfs, &rtrack, fs->io);
 163
 164         init_resource_track(&rtrack, "inode_ref_fix", fs->io);
 165         retval = inode_ref_fix(rfs);
 166         if (retval)
 167                 goto errout;
 168         print_resource_track(rfs, &rtrack, fs->io);
 169
 170         init_resource_track(&rtrack, "move_itables", fs->io);
 171         retval = move_itables(rfs);
 172         if (retval)
 173                 goto errout;
 174         print_resource_track(rfs, &rtrack, fs->io);
 175
 176         init_resource_track(&rtrack, "calculate_summary_stats", fs->io);
 177         retval = ext2fs_calculate_summary_stats(rfs->new_fs);
 178         if (retval)
 179                 goto errout;
 180         print_resource_track(rfs, &rtrack, fs->io);
 181
 182         init_resource_track(&rtrack, "fix_resize_inode", fs->io);
 183         retval = fix_resize_inode(rfs->new_fs);
 184         if (retval)
 185                 goto errout;
 186         print_resource_track(rfs, &rtrack, fs->io);
 187
 188         init_resource_track(&rtrack, "fix_sb_journal_backup", fs->io);
 189         retval = fix_sb_journal_backup(rfs->new_fs);
 190         if (retval)
 191                 goto errout;
 192         print_resource_track(rfs, &rtrack, fs->io);
 193
 194         rfs->new_fs->super->s_state &= ~EXT2_ERROR_FS;
 195         rfs->new_fs->flags &= ~EXT2_FLAG_MASTER_SB_ONLY;
 196
 197         print_resource_track(rfs, &overall_track, fs->io);
 198         retval = ext2fs_close(rfs->new_fs);
 199         if (retval)
 200                 goto errout;
 201
 202         rfs->flags = flags;
 203
 204         ext2fs_free(rfs->old_fs);
 205         if (rfs->itable_buf)
 206                 ext2fs_free_mem(&rfs->itable_buf);
 207         if (rfs->reserve_blocks)
 208                 ext2fs_free_block_bitmap(rfs->reserve_blocks);
 209         if (rfs->move_blocks)
 210                 ext2fs_free_block_bitmap(rfs->move_blocks);
 211         ext2fs_free_mem(&rfs);
 212
 213         return 0;
 214
 215 errout:
 216         if (rfs->new_fs)
 217                 ext2fs_free(rfs->new_fs);
 218         if (rfs->itable_buf)
 219                 ext2fs_free_mem(&rfs->itable_buf);
 220         ext2fs_free_mem(&rfs);
 221         return retval;
 222 }
 223
 224 /*
 225  * Clean up the bitmaps for unitialized bitmaps
 226  */
 227 static void fix_uninit_block_bitmaps(ext2_filsys fs)
 228 {
 229         blk64_t         blk, lblk;
 230         dgrp_t          g;
 231         int             i;
 232
 233         if (!(EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
 234                                          EXT4_FEATURE_RO_COMPAT_GDT_CSUM)))
 235                 return;
 236
 237         for (g=0; g < fs->group_desc_count; g++) {
 238                 if (!(ext2fs_bg_flags_test(fs, g, EXT2_BG_BLOCK_UNINIT)))
 239                         continue;
 240
 241                 blk = ext2fs_group_first_block2(fs, g);
 242                 lblk = ext2fs_group_last_block2(fs, g);
 243                 ext2fs_unmark_block_bitmap_range2(fs->block_map, blk,
 244                                                   lblk - blk + 1);
 245
 246                 ext2fs_reserve_super_and_bgd(fs, g, fs->block_map);
 247                 ext2fs_mark_block_bitmap2(fs->block_map,
 248                                           ext2fs_block_bitmap_loc(fs, g));
 249                 ext2fs_mark_block_bitmap2(fs->block_map,
 250                                           ext2fs_inode_bitmap_loc(fs, g));
 251                 for (i = 0, blk = ext2fs_inode_table_loc(fs, g);
 252                      i < (unsigned int) fs->inode_blocks_per_group;
 253                      i++, blk++)
 254                         ext2fs_mark_block_bitmap2(fs->block_map, blk);
 255         }
 256 }
 257
 258 /* --------------------------------------------------------------------
 259  *
 260  * Resize processing, phase 1.
 261  *
 262  * In this phase we adjust the in-memory superblock information, and
 263  * initialize any new parts of the inode table.  The new parts of the
 264  * inode table are created in virgin disk space, so we can abort here
 265  * without any side effects.
 266  * --------------------------------------------------------------------
 267  */
 268
 269 /*
 270  * If the group descriptor's bitmap and inode table blocks are valid,
 271  * release them in the new filesystem data structure, and mark them as
 272  * reserved so the old inode table blocks don't get overwritten.
 273  */
 274 static void free_gdp_blocks(ext2_filsys fs,
 275                             ext2fs_block_bitmap reserve_blocks,
 276                             ext2_filsys old_fs,
 277                             dgrp_t group)
 278 {
 279         blk64_t blk;
 280         int     j;
 281
 282         blk = ext2fs_block_bitmap_loc(old_fs, group);
 283         if (blk &&
 284             (blk < ext2fs_blocks_count(fs->super))) {
 285                 ext2fs_block_alloc_stats2(fs, blk, -1);
 286                 ext2fs_mark_block_bitmap2(reserve_blocks, blk);
 287         }
 288
 289         blk = ext2fs_inode_bitmap_loc(old_fs, group);
 290         if (blk &&
 291             (blk < ext2fs_blocks_count(fs->super))) {
 292                 ext2fs_block_alloc_stats2(fs, blk, -1);
 293                 ext2fs_mark_block_bitmap2(reserve_blocks, blk);
 294         }
 295
 296         blk = ext2fs_inode_table_loc(old_fs, group);
 297         if (blk == 0 ||
 298             (blk >= ext2fs_blocks_count(fs->super)))
 299                 return;
 300
 301         for (j = 0;
 302              j < fs->inode_blocks_per_group; j++, blk++) {
 303                 if (blk >= ext2fs_blocks_count(fs->super))
 304                         break;
 305                 ext2fs_block_alloc_stats2(fs, blk, -1);
 306                 ext2fs_mark_block_bitmap2(reserve_blocks, blk);
 307         }
 308 }
 309
 310 /*
 311  * This routine is shared by the online and offline resize routines.
 312  * All of the information which is adjusted in memory is done here.
 313  */
 314 errcode_t adjust_fs_info(ext2_filsys fs, ext2_filsys old_fs,
 315                          ext2fs_block_bitmap reserve_blocks, blk64_t new_size)
 316 {
 317         errcode_t       retval;
 318         blk64_t         overhead = 0;
 319         blk64_t         rem;
 320         blk64_t         blk, group_block;
 321         blk64_t         real_end;
 322         blk64_t         old_numblocks, numblocks, adjblocks;
 323         unsigned long   i, j, old_desc_blocks;
 324         unsigned int    meta_bg, meta_bg_size;
 325         int             has_super, csum_flag;
 326         unsigned long long new_inodes;  /* u64 to check for overflow */
 327         double          percent;
 328
 329         ext2fs_blocks_count_set(fs->super, new_size);
 330
 331 retry:
 332         fs->group_desc_count = ext2fs_div64_ceil(ext2fs_blocks_count(fs->super) -
 333                                        fs->super->s_first_data_block,
 334                                        EXT2_BLOCKS_PER_GROUP(fs->super));
 335         if (fs->group_desc_count == 0)
 336                 return EXT2_ET_TOOSMALL;
 337         fs->desc_blocks = ext2fs_div_ceil(fs->group_desc_count,
 338                                           EXT2_DESC_PER_BLOCK(fs->super));
 339
 340         /*
 341          * Overhead is the number of bookkeeping blocks per group.  It
 342          * includes the superblock backup, the group descriptor
 343          * backups, the inode bitmap, the block bitmap, and the inode
 344          * table.
 345          */
 346         overhead = (int) (2 + fs->inode_blocks_per_group);
 347
 348         if (ext2fs_bg_has_super(fs, fs->group_desc_count - 1))
 349                 overhead += 1 + fs->desc_blocks +
 350                         fs->super->s_reserved_gdt_blocks;
 351
 352         /*
 353          * See if the last group is big enough to support the
 354          * necessary data structures.  If not, we need to get rid of
 355          * it.
 356          */
 357         rem = (ext2fs_blocks_count(fs->super) - fs->super->s_first_data_block) %
 358                 fs->super->s_blocks_per_group;
 359         if ((fs->group_desc_count == 1) && rem && (rem < overhead))
 360                 return EXT2_ET_TOOSMALL;
 361         if ((fs->group_desc_count > 1) && rem && (rem < overhead+50)) {
 362                 ext2fs_blocks_count_set(fs->super,
 363                                         ext2fs_blocks_count(fs->super) - rem);
 364                 goto retry;
 365         }
 366         /*
 367          * Adjust the number of inodes
 368          */
 369         new_inodes =(unsigned long long) fs->super->s_inodes_per_group * fs->group_desc_count;
 370         if (new_inodes > ~0U) {
 371                 fprintf(stderr, _("inodes (%llu) must be less than %u"),
 372                                    new_inodes, ~0U);
 373                 return EXT2_ET_TOO_MANY_INODES;
 374         }
 375         fs->super->s_inodes_count = fs->super->s_inodes_per_group *
 376                 fs->group_desc_count;
 377
 378         /*
 379          * Adjust the number of free blocks
 380          */
 381         blk = ext2fs_blocks_count(old_fs->super);
 382         if (blk > ext2fs_blocks_count(fs->super))
 383                 ext2fs_free_blocks_count_set(fs->super,
 384                         ext2fs_free_blocks_count(fs->super) -
 385                         (blk - ext2fs_blocks_count(fs->super)));
 386         else
 387                 ext2fs_free_blocks_count_set(fs->super,
 388                         ext2fs_free_blocks_count(fs->super) +
 389                         (ext2fs_blocks_count(fs->super) - blk));
 390
 391         /*
 392          * Adjust the number of reserved blocks
 393          */
 394         percent = (ext2fs_r_blocks_count(old_fs->super) * 100.0) /
 395                 ext2fs_blocks_count(old_fs->super);
 396         ext2fs_r_blocks_count_set(fs->super,
 397                                   (percent * ext2fs_blocks_count(fs->super) /
 398                                    100.0));
 399
 400         /*
 401          * Adjust the bitmaps for size
 402          */
 403         retval = ext2fs_resize_inode_bitmap2(fs->super->s_inodes_count,
 404                                             fs->super->s_inodes_count,
 405                                             fs->inode_map);
 406         if (retval) goto errout;
 407
 408         real_end = (((blk64_t) EXT2_BLOCKS_PER_GROUP(fs->super) *
 409                      fs->group_desc_count)) - 1 +
 410                 fs->super->s_first_data_block;
 411         retval = ext2fs_resize_block_bitmap2(new_size - 1,
 412                                              real_end, fs->block_map);
 413         if (retval) goto errout;
 414
 415         /*
 416          * If we are growing the file system, also grow the size of
 417          * the reserve_blocks bitmap
 418          */
 419         if (reserve_blocks && new_size > ext2fs_blocks_count(old_fs->super)) {
 420                 retval = ext2fs_resize_block_bitmap2(new_size - 1,
 421                                                      real_end, reserve_blocks);
 422                 if (retval) goto errout;
 423         }
 424
 425         /*
 426          * Reallocate the group descriptors as necessary.
 427          */
 428         if (old_fs->desc_blocks != fs->desc_blocks) {
 429                 retval = ext2fs_resize_mem(old_fs->desc_blocks *
 430                                            fs->blocksize,
 431                                            fs->desc_blocks * fs->blocksize,
 432                                            &fs->group_desc);
 433                 if (retval)
 434                         goto errout;
 435                 if (fs->desc_blocks > old_fs->desc_blocks)
 436                         memset((char *) fs->group_desc +
 437                                (old_fs->desc_blocks * fs->blocksize), 0,
 438                                (fs->desc_blocks - old_fs->desc_blocks) *
 439                                fs->blocksize);
 440         }
 441
 442         /*
 443          * If the resize_inode feature is set, and we are changing the
 444          * number of descriptor blocks, then adjust
 445          * s_reserved_gdt_blocks if possible to avoid needing to move
 446          * the inode table either now or in the future.
 447          */
 448         if ((fs->super->s_feature_compat &
 449              EXT2_FEATURE_COMPAT_RESIZE_INODE) &&
 450             (old_fs->desc_blocks != fs->desc_blocks)) {
 451                 int new;
 452
 453                 new = ((int) fs->super->s_reserved_gdt_blocks) +
 454                         (old_fs->desc_blocks - fs->desc_blocks);
 455                 if (new < 0)
 456                         new = 0;
 457                 if (new > (int) fs->blocksize/4)
 458                         new = fs->blocksize/4;
 459                 fs->super->s_reserved_gdt_blocks = new;
 460         }
 461
 462         /*
 463          * If we are shrinking the number of block groups, we're done
 464          * and can exit now.
 465          */
 466         if (old_fs->group_desc_count > fs->group_desc_count) {
 467                 /*
 468                  * Check the block groups that we are chopping off
 469                  * and free any blocks associated with their metadata
 470                  */
 471                 for (i = fs->group_desc_count;
 472                      i < old_fs->group_desc_count; i++)
 473                         free_gdp_blocks(fs, reserve_blocks, old_fs, i);
 474                 retval = 0;
 475                 goto errout;
 476         }
 477
 478         /*
 479          * Fix the count of the last (old) block group
 480          */
 481         old_numblocks = (ext2fs_blocks_count(old_fs->super) -
 482                          old_fs->super->s_first_data_block) %
 483                                  old_fs->super->s_blocks_per_group;
 484         if (!old_numblocks)
 485                 old_numblocks = old_fs->super->s_blocks_per_group;
 486         if (old_fs->group_desc_count == fs->group_desc_count) {
 487                 numblocks = (ext2fs_blocks_count(fs->super) -
 488                              fs->super->s_first_data_block) %
 489                         fs->super->s_blocks_per_group;
 490                 if (!numblocks)
 491                         numblocks = fs->super->s_blocks_per_group;
 492         } else
 493                 numblocks = fs->super->s_blocks_per_group;
 494         i = old_fs->group_desc_count - 1;
 495         ext2fs_bg_free_blocks_count_set(fs, i, ext2fs_bg_free_blocks_count(fs, i) + (numblocks - old_numblocks));
 496         ext2fs_group_desc_csum_set(fs, i);
 497
 498         /*
 499          * If the number of block groups is staying the same, we're
 500          * done and can exit now.  (If the number block groups is
 501          * shrinking, we had exited earlier.)
 502          */
 503         if (old_fs->group_desc_count >= fs->group_desc_count) {
 504                 retval = 0;
 505                 goto errout;
 506         }
 507
 508         /*
 509          * Initialize the new block group descriptors
 510          */
 511         group_block = ext2fs_group_first_block2(fs,
 512                                                 old_fs->group_desc_count);
 513         csum_flag = EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
 514                                                EXT4_FEATURE_RO_COMPAT_GDT_CSUM);
 515         if (access("/sys/fs/ext4/features/lazy_itable_init", F_OK) == 0)
 516                 lazy_itable_init = 1;
 517         if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
 518                 old_desc_blocks = fs->super->s_first_meta_bg;
 519         else
 520                 old_desc_blocks = fs->desc_blocks +
 521                         fs->super->s_reserved_gdt_blocks;
 522
 523         /*
 524          * If we changed the number of block_group descriptor blocks,
 525          * we need to make sure they are all marked as reserved in the
 526          * file systems's block allocation map.
 527          */
 528         for (i = 0; i < old_fs->group_desc_count; i++)
 529                 ext2fs_reserve_super_and_bgd(fs, i, fs->block_map);
 530
 531         for (i = old_fs->group_desc_count;
 532              i < fs->group_desc_count; i++) {
 533                 memset(ext2fs_group_desc(fs, fs->group_desc, i), 0,
 534                        sizeof(struct ext2_group_desc));
 535                 adjblocks = 0;
 536
 537                 ext2fs_bg_flags_zap(fs, i);
 538                 if (csum_flag) {
 539                         ext2fs_bg_flags_set(fs, i, EXT2_BG_INODE_UNINIT);
 540                         if (!lazy_itable_init)
 541                                 ext2fs_bg_flags_set(fs, i,
 542                                                     EXT2_BG_INODE_ZEROED);
 543                         ext2fs_bg_itable_unused_set(fs, i,
 544                                         fs->super->s_inodes_per_group);
 545                 }
 546
 547                 numblocks = ext2fs_group_blocks_count(fs, i);
 548                 if ((i < fs->group_desc_count - 1) && csum_flag)
 549                         ext2fs_bg_flags_set(fs, i, EXT2_BG_BLOCK_UNINIT);
 550
 551                 has_super = ext2fs_bg_has_super(fs, i);
 552                 if (has_super) {
 553                         ext2fs_block_alloc_stats2(fs, group_block, +1);
 554                         adjblocks++;
 555                 }
 556                 meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
 557                 meta_bg = i / meta_bg_size;
 558                 if (!(fs->super->s_feature_incompat &
 559                       EXT2_FEATURE_INCOMPAT_META_BG) ||
 560                     (meta_bg < fs->super->s_first_meta_bg)) {
 561                         if (has_super) {
 562                                 for (j=0; j < old_desc_blocks; j++)
 563                                         ext2fs_block_alloc_stats2(fs,
 564                                                  group_block + 1 + j, +1);
 565                                 adjblocks += old_desc_blocks;
 566                         }
 567                 } else {
 568                         if (has_super)
 569                                 has_super = 1;
 570                         if (((i % meta_bg_size) == 0) ||
 571                             ((i % meta_bg_size) == 1) ||
 572                             ((i % meta_bg_size) == (meta_bg_size-1)))
 573                                 ext2fs_block_alloc_stats2(fs,
 574                                                  group_block + has_super, +1);
 575                 }
 576
 577                 adjblocks += 2 + fs->inode_blocks_per_group;
 578
 579                 numblocks -= adjblocks;
 580                 ext2fs_free_blocks_count_set(fs->super,
 581                              ext2fs_free_blocks_count(fs->super) - adjblocks);
 582                 fs->super->s_free_inodes_count +=
 583                         fs->super->s_inodes_per_group;
 584                 ext2fs_bg_free_blocks_count_set(fs, i, numblocks);
 585                 ext2fs_bg_free_inodes_count_set(fs, i,
 586                                                 fs->super->s_inodes_per_group);
 587                 ext2fs_bg_used_dirs_count_set(fs, i, 0);
 588                 ext2fs_group_desc_csum_set(fs, i);
 589
 590                 retval = ext2fs_allocate_group_table(fs, i, 0);
 591                 if (retval) goto errout;
 592
 593                 group_block += fs->super->s_blocks_per_group;
 594         }
 595         retval = 0;
 596
 597         /*
 598          * Mark all of the metadata blocks as reserved so they won't
 599          * get allocated by the call to ext2fs_allocate_group_table()
 600          * in blocks_to_move(), where we allocate new blocks to
 601          * replace those allocation bitmap and inode table blocks
 602          * which have to get relocated to make space for an increased
 603          * number of the block group descriptors.
 604          */
 605         if (reserve_blocks)
 606                 mark_table_blocks(fs, reserve_blocks);
 607
 608 errout:
 609         return (retval);
 610 }
 611
 612 /*
 613  * This routine adjusts the superblock and other data structures, both
 614  * in disk as well as in memory...
 615  */
 616 static errcode_t adjust_superblock(ext2_resize_t rfs, blk64_t new_size)
 617 {
 618         ext2_filsys fs;
 619         int             adj = 0;
 620         errcode_t       retval;
 621         blk64_t         group_block;
 622         unsigned long   i;
 623         unsigned long   max_group;
 624
 625         fs = rfs->new_fs;
 626         ext2fs_mark_super_dirty(fs);
 627         ext2fs_mark_bb_dirty(fs);
 628         ext2fs_mark_ib_dirty(fs);
 629
 630         retval = ext2fs_allocate_block_bitmap(fs, _("reserved blocks"),
 631                                               &rfs->reserve_blocks);
 632         if (retval)
 633                 return retval;
 634
 635         retval = adjust_fs_info(fs, rfs->old_fs, rfs->reserve_blocks, new_size);
 636         if (retval)
 637                 goto errout;
 638
 639         /*
 640          * Check to make sure there are enough inodes
 641          */
 642         if ((rfs->old_fs->super->s_inodes_count -
 643              rfs->old_fs->super->s_free_inodes_count) >
 644             rfs->new_fs->super->s_inodes_count) {
 645                 retval = ENOSPC;
 646                 goto errout;
 647         }
 648
 649         /*
 650          * If we are shrinking the number block groups, we're done and
 651          * can exit now.
 652          */
 653         if (rfs->old_fs->group_desc_count > fs->group_desc_count) {
 654                 retval = 0;
 655                 goto errout;
 656         }
 657
 658         /*
 659          * If the number of block groups is staying the same, we're
 660          * done and can exit now.  (If the number block groups is
 661          * shrinking, we had exited earlier.)
 662          */
 663         if (rfs->old_fs->group_desc_count >= fs->group_desc_count) {
 664                 retval = 0;
 665                 goto errout;
 666         }
 667
 668         /*
 669          * If we are using uninit_bg (aka GDT_CSUM) and the kernel
 670          * supports lazy inode initialization, we can skip
 671          * initializing the inode table.
 672          */
 673         if (lazy_itable_init &&
 674             EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
 675                                        EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
 676                 retval = 0;
 677                 goto errout;
 678         }
 679
 680         /*
 681          * Initialize the inode table
 682          */
 683         retval = ext2fs_get_array(fs->blocksize, fs->inode_blocks_per_group,
 684                                 &rfs->itable_buf);
 685         if (retval)
 686                 goto errout;
 687
 688         memset(rfs->itable_buf, 0, fs->blocksize * fs->inode_blocks_per_group);
 689         group_block = ext2fs_group_first_block2(fs,
 690                                                 rfs->old_fs->group_desc_count);
 691         adj = rfs->old_fs->group_desc_count;
 692         max_group = fs->group_desc_count - adj;
 693         if (rfs->progress) {
 694                 retval = rfs->progress(rfs, E2_RSZ_EXTEND_ITABLE_PASS,
 695                                        0, max_group);
 696                 if (retval)
 697                         goto errout;
 698         }
 699         for (i = rfs->old_fs->group_desc_count;
 700              i < fs->group_desc_count; i++) {
 701                 /*
 702                  * Write out the new inode table
 703                  */
 704                 retval = io_channel_write_blk64(fs->io,
 705                                                 ext2fs_inode_table_loc(fs, i),
 706                                                 fs->inode_blocks_per_group,
 707                                                 rfs->itable_buf);
 708                 if (retval) goto errout;
 709
 710                 io_channel_flush(fs->io);
 711                 if (rfs->progress) {
 712                         retval = rfs->progress(rfs, E2_RSZ_EXTEND_ITABLE_PASS,
 713                                                i - adj + 1, max_group);
 714                         if (retval)
 715                                 goto errout;
 716                 }
 717                 group_block += fs->super->s_blocks_per_group;
 718         }
 719         io_channel_flush(fs->io);
 720         retval = 0;
 721
 722 errout:
 723         return retval;
 724 }
 725
 726 /* --------------------------------------------------------------------
 727  *
 728  * Resize processing, phase 2.
 729  *
 730  * In this phase we adjust determine which blocks need to be moved, in
 731  * blocks_to_move().  We then copy the blocks to their ultimate new
 732  * destinations using block_mover().  Since we are copying blocks to
 733  * their new locations, again during this pass we can abort without
 734  * any problems.
 735  * --------------------------------------------------------------------
 736  */
 737
 738 /*
 739  * This helper function creates a block bitmap with all of the
 740  * filesystem meta-data blocks.
 741  */
 742 static errcode_t mark_table_blocks(ext2_filsys fs,
 743                                    ext2fs_block_bitmap bmap)
 744 {
 745         dgrp_t                  i;
 746         blk64_t                 blk;
 747
 748         for (i = 0; i < fs->group_desc_count; i++) {
 749                 ext2fs_reserve_super_and_bgd(fs, i, bmap);
 750
 751                 /*
 752                  * Mark the blocks used for the inode table
 753                  */
 754                 blk = ext2fs_inode_table_loc(fs, i);
 755                 if (blk)
 756                         ext2fs_mark_block_bitmap_range2(bmap, blk,
 757                                                 fs->inode_blocks_per_group);
 758
 759                 /*
 760                  * Mark block used for the block bitmap
 761                  */
 762                 blk = ext2fs_block_bitmap_loc(fs, i);
 763                 if (blk)
 764                         ext2fs_mark_block_bitmap2(bmap, blk);
 765
 766                 /*
 767                  * Mark block used for the inode bitmap
 768                  */
 769                 blk = ext2fs_inode_bitmap_loc(fs, i);
 770                 if (blk)
 771                         ext2fs_mark_block_bitmap2(bmap, blk);
 772         }
 773         return 0;
 774 }
 775
 776 /*
 777  * This function checks to see if a particular block (either a
 778  * superblock or a block group descriptor) overlaps with an inode or
 779  * block bitmap block, or with the inode table.
 780  */
 781 static void mark_fs_metablock(ext2_resize_t rfs,
 782                               ext2fs_block_bitmap meta_bmap,
 783                               int group, blk64_t blk)
 784 {
 785         ext2_filsys     fs = rfs->new_fs;
 786
 787         ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
 788         ext2fs_block_alloc_stats2(fs, blk, +1);
 789
 790         /*
 791          * Check to see if we overlap with the inode or block bitmap,
 792          * or the inode tables.  If not, and the block is in use, then
 793          * mark it as a block to be moved.
 794          */
 795         if (IS_BLOCK_BM(fs, group, blk)) {
 796                 ext2fs_block_bitmap_loc_set(fs, group, 0);
 797                 rfs->needed_blocks++;
 798                 return;
 799         }
 800         if (IS_INODE_BM(fs, group, blk)) {
 801                 ext2fs_inode_bitmap_loc_set(fs, group, 0);
 802                 rfs->needed_blocks++;
 803                 return;
 804         }
 805         if (IS_INODE_TB(fs, group, blk)) {
 806                 ext2fs_inode_table_loc_set(fs, group, 0);
 807                 rfs->needed_blocks++;
 808                 return;
 809         }
 810         if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_FLEX_BG) {
 811                 dgrp_t i;
 812
 813                 for (i=0; i < rfs->old_fs->group_desc_count; i++) {
 814                         if (IS_BLOCK_BM(fs, i, blk)) {
 815                                 ext2fs_block_bitmap_loc_set(fs, i, 0);
 816                                 rfs->needed_blocks++;
 817                                 return;
 818                         }
 819                         if (IS_INODE_BM(fs, i, blk)) {
 820                                 ext2fs_inode_bitmap_loc_set(fs, i, 0);
 821                                 rfs->needed_blocks++;
 822                                 return;
 823                         }
 824                         if (IS_INODE_TB(fs, i, blk)) {
 825                                 ext2fs_inode_table_loc_set(fs, i, 0);
 826                                 rfs->needed_blocks++;
 827                                 return;
 828                         }
 829                 }
 830         }
 831         if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
 832                                        EXT4_FEATURE_RO_COMPAT_GDT_CSUM) &&
 833                    (ext2fs_bg_flags_test(fs, group, EXT2_BG_BLOCK_UNINIT))) {
 834                 /*
 835                  * If the block bitmap is uninitialized, which means
 836                  * nothing other than standard metadata in use.
 837                  */
 838                 return;
 839         } else if (ext2fs_test_block_bitmap2(rfs->old_fs->block_map, blk) &&
 840                    !ext2fs_test_block_bitmap2(meta_bmap, blk)) {
 841                 ext2fs_mark_block_bitmap2(rfs->move_blocks, blk);
 842                 rfs->needed_blocks++;
 843         }
 844 }
 845
 846
 847 /*
 848  * This routine marks and unmarks reserved blocks in the new block
 849  * bitmap.  It also determines which blocks need to be moved and
 850  * places this information into the move_blocks bitmap.
 851  */
 852 static errcode_t blocks_to_move(ext2_resize_t rfs)
 853 {
 854         int             j, has_super;
 855         dgrp_t          i, max_groups, g;
 856         blk64_t         blk, group_blk;
 857         blk64_t         old_blocks, new_blocks;
 858         blk64_t         new_size;
 859         unsigned int    meta_bg, meta_bg_size;
 860         errcode_t       retval;
 861         ext2_filsys     fs, old_fs;
 862         ext2fs_block_bitmap     meta_bmap;
 863         int             flex_bg;
 864
 865         fs = rfs->new_fs;
 866         old_fs = rfs->old_fs;
 867         if (ext2fs_blocks_count(old_fs->super) > ext2fs_blocks_count(fs->super))
 868                 fs = rfs->old_fs;
 869
 870         retval = ext2fs_allocate_block_bitmap(fs, _("blocks to be moved"),
 871                                               &rfs->move_blocks);
 872         if (retval)
 873                 return retval;
 874
 875         retval = ext2fs_allocate_block_bitmap(fs, _("meta-data blocks"),
 876                                               &meta_bmap);
 877         if (retval)
 878                 return retval;
 879
 880         retval = mark_table_blocks(old_fs, meta_bmap);
 881         if (retval)
 882                 return retval;
 883
 884         fs = rfs->new_fs;
 885
 886         /*
 887          * If we're shrinking the filesystem, we need to move any group's
 888          * bitmaps which are beyond the end of the new filesystem.
 889          */
 890         new_size = ext2fs_blocks_count(fs->super);
 891         if (new_size < ext2fs_blocks_count(old_fs->super)) {
 892                 for (g = 0; g < fs->group_desc_count; g++) {
 893                         /*
 894                          * ext2fs_allocate_group_table re-allocates bitmaps
 895                          * which are set to block 0.
 896                          */
 897                         if (ext2fs_block_bitmap_loc(fs, g) >= new_size) {
 898                                 ext2fs_block_bitmap_loc_set(fs, g, 0);
 899                                 retval = ext2fs_allocate_group_table(fs, g, 0);
 900                                 if (retval)
 901                                         return retval;
 902                         }
 903                         if (ext2fs_inode_bitmap_loc(fs, g) >= new_size) {
 904                                 ext2fs_inode_bitmap_loc_set(fs, g, 0);
 905                                 retval = ext2fs_allocate_group_table(fs, g, 0);
 906                                 if (retval)
 907                                         return retval;
 908                         }
 909                 }
 910         }
 911
 912         /*
 913          * If we're shrinking the filesystem, we need to move all of
 914          * the blocks that don't fit any more
 915          */
 916         for (blk = ext2fs_blocks_count(fs->super);
 917              blk < ext2fs_blocks_count(old_fs->super); blk++) {
 918                 g = ext2fs_group_of_blk2(fs, blk);
 919                 if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
 920                                                EXT4_FEATURE_RO_COMPAT_GDT_CSUM) &&
 921                     ext2fs_bg_flags_test(old_fs, g, EXT2_BG_BLOCK_UNINIT)) {
 922                         /*
 923                          * The block bitmap is uninitialized, so skip
 924                          * to the next block group.
 925                          */
 926                         blk = ext2fs_group_first_block2(fs, g+1) - 1;
 927                         continue;
 928                 }
 929                 if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
 930                     !ext2fs_test_block_bitmap2(meta_bmap, blk)) {
 931                         ext2fs_mark_block_bitmap2(rfs->move_blocks, blk);
 932                         rfs->needed_blocks++;
 933                 }
 934                 ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
 935         }
 936
 937         if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG) {
 938                 old_blocks = old_fs->super->s_first_meta_bg;
 939                 new_blocks = fs->super->s_first_meta_bg;
 940         } else {
 941                 old_blocks = old_fs->desc_blocks + old_fs->super->s_reserved_gdt_blocks;
 942                 new_blocks = fs->desc_blocks + fs->super->s_reserved_gdt_blocks;
 943         }
 944
 945         if (old_blocks == new_blocks) {
 946                 retval = 0;
 947                 goto errout;
 948         }
 949
 950         max_groups = fs->group_desc_count;
 951         if (max_groups > old_fs->group_desc_count)
 952                 max_groups = old_fs->group_desc_count;
 953         group_blk = old_fs->super->s_first_data_block;
 954         /*
 955          * If we're reducing the number of descriptor blocks, this
 956          * makes life easy.  :-)   We just have to mark some extra
 957          * blocks as free.
 958          */
 959         if (old_blocks > new_blocks) {
 960                 for (i = 0; i < max_groups; i++) {
 961                         if (!ext2fs_bg_has_super(fs, i)) {
 962                                 group_blk += fs->super->s_blocks_per_group;
 963                                 continue;
 964                         }
 965                         for (blk = group_blk+1+new_blocks;
 966                              blk < group_blk+1+old_blocks; blk++) {
 967                                 ext2fs_block_alloc_stats2(fs, blk, -1);
 968                                 rfs->needed_blocks--;
 969                         }
 970                         group_blk += fs->super->s_blocks_per_group;
 971                 }
 972                 retval = 0;
 973                 goto errout;
 974         }
 975         /*
 976          * If we're increasing the number of descriptor blocks, life
 977          * gets interesting....
 978          */
 979         meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
 980         flex_bg = fs->super->s_feature_incompat &
 981                 EXT4_FEATURE_INCOMPAT_FLEX_BG;
 982         /* first reserve all of the existing fs meta blocks */
 983         for (i = 0; i < max_groups; i++) {
 984                 has_super = ext2fs_bg_has_super(fs, i);
 985                 if (has_super)
 986                         mark_fs_metablock(rfs, meta_bmap, i, group_blk);
 987
 988                 meta_bg = i / meta_bg_size;
 989                 if (!(fs->super->s_feature_incompat &
 990                       EXT2_FEATURE_INCOMPAT_META_BG) ||
 991                     (meta_bg < fs->super->s_first_meta_bg)) {
 992                         if (has_super) {
 993                                 for (blk = group_blk+1;
 994                                      blk < group_blk + 1 + new_blocks; blk++)
 995                                         mark_fs_metablock(rfs, meta_bmap,
 996                                                           i, blk);
 997                         }
 998                 } else {
 999                         if (has_super)
1000                                 has_super = 1;
1001                         if (((i % meta_bg_size) == 0) ||
1002                             ((i % meta_bg_size) == 1) ||
1003                             ((i % meta_bg_size) == (meta_bg_size-1)))
1004                                 mark_fs_metablock(rfs, meta_bmap, i,
1005                                                   group_blk + has_super);
1006                 }
1007
1008                 /*
1009                  * Reserve the existing meta blocks that we know
1010                  * aren't to be moved.
1011                  *
1012                  * For flex_bg file systems, in order to avoid
1013                  * overwriting fs metadata (especially inode table
1014                  * blocks) belonging to a different block group when
1015                  * we are relocating the inode tables, we need to
1016                  * reserve all existing fs metadata blocks.
1017                  */
1018                 if (ext2fs_block_bitmap_loc(fs, i))
1019                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
1020                                  ext2fs_block_bitmap_loc(fs, i));
1021                 else if (flex_bg && i < old_fs->group_desc_count)
1022                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
1023                                  ext2fs_block_bitmap_loc(old_fs, i));
1024
1025                 if (ext2fs_inode_bitmap_loc(fs, i))
1026                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
1027                                  ext2fs_inode_bitmap_loc(fs, i));
1028                 else if (flex_bg && i < old_fs->group_desc_count)
1029                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
1030                                  ext2fs_inode_bitmap_loc(old_fs, i));
1031
1032                 if (ext2fs_inode_table_loc(fs, i))
1033                         ext2fs_mark_block_bitmap_range2(rfs->reserve_blocks,
1034                                         ext2fs_inode_table_loc(fs, i),
1035                                         fs->inode_blocks_per_group);
1036                 else if (flex_bg && i < old_fs->group_desc_count)
1037                         ext2fs_mark_block_bitmap_range2(rfs->reserve_blocks,
1038                                         ext2fs_inode_table_loc(old_fs, i),
1039                                         old_fs->inode_blocks_per_group);
1040
1041                 group_blk += rfs->new_fs->super->s_blocks_per_group;
1042         }
1043
1044         /* Allocate the missing data structures */
1045         for (i = 0; i < max_groups; i++) {
1046                 if (ext2fs_inode_table_loc(fs, i) &&
1047                     ext2fs_inode_bitmap_loc(fs, i) &&
1048                     ext2fs_block_bitmap_loc(fs, i))
1049                         continue;
1050
1051                 retval = ext2fs_allocate_group_table(fs, i,
1052                                                      rfs->reserve_blocks);
1053                 if (retval)
1054                         goto errout;
1055
1056                 /*
1057                  * For those structures that have changed, we need to
1058                  * do bookkeepping.
1059                  */
1060                 if (ext2fs_block_bitmap_loc(old_fs, i) !=
1061                     (blk = ext2fs_block_bitmap_loc(fs, i))) {
1062                         ext2fs_block_alloc_stats2(fs, blk, +1);
1063                         if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
1064                             !ext2fs_test_block_bitmap2(meta_bmap, blk))
1065                                 ext2fs_mark_block_bitmap2(rfs->move_blocks,
1066                                                          blk);
1067                 }
1068                 if (ext2fs_inode_bitmap_loc(old_fs, i) !=
1069                     (blk = ext2fs_inode_bitmap_loc(fs, i))) {
1070                         ext2fs_block_alloc_stats2(fs, blk, +1);
1071                         if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
1072                             !ext2fs_test_block_bitmap2(meta_bmap, blk))
1073                                 ext2fs_mark_block_bitmap2(rfs->move_blocks,
1074                                                          blk);
1075                 }
1076
1077                 /*
1078                  * The inode table, if we need to relocate it, is
1079                  * handled specially.  We have to reserve the blocks
1080                  * for both the old and the new inode table, since we
1081                  * can't have the inode table be destroyed during the
1082                  * block relocation phase.
1083                  */
1084                 if (ext2fs_inode_table_loc(fs, i) == ext2fs_inode_table_loc(old_fs, i))
1085                         continue;       /* inode table not moved */
1086
1087                 rfs->needed_blocks += fs->inode_blocks_per_group;
1088
1089                 /*
1090                  * Mark the new inode table as in use in the new block
1091                  * allocation bitmap, and move any blocks that might
1092                  * be necessary.
1093                  */
1094                 for (blk = ext2fs_inode_table_loc(fs, i), j=0;
1095                      j < fs->inode_blocks_per_group ; j++, blk++) {
1096                         ext2fs_block_alloc_stats2(fs, blk, +1);
1097                         if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
1098                             !ext2fs_test_block_bitmap2(meta_bmap, blk))
1099                                 ext2fs_mark_block_bitmap2(rfs->move_blocks,
1100                                                          blk);
1101                 }
1102
1103                 /*
1104                  * Make sure the old inode table is reserved in the
1105                  * block reservation bitmap.
1106                  */
1107                 for (blk = ext2fs_inode_table_loc(rfs->old_fs, i), j=0;
1108                      j < fs->inode_blocks_per_group ; j++, blk++)
1109                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
1110         }
1111         retval = 0;
1112
1113 errout:
1114         if (meta_bmap)
1115                 ext2fs_free_block_bitmap(meta_bmap);
1116
1117         return retval;
1118 }
1119
1120 /*
1121  * This helper function tries to allocate a new block.  We try to
1122  * avoid hitting the original group descriptor blocks at least at
1123  * first, since we want to make it possible to recover from a badly
1124  * aborted resize operation as much as possible.
1125  *
1126  * In the future, I may further modify this routine to balance out
1127  * where we get the new blocks across the various block groups.
1128  * Ideally we would allocate blocks that corresponded with the block
1129  * group of the containing inode, and keep contiguous blocks
1130  * together.  However, this very difficult to do efficiently, since we
1131  * don't have the necessary information up front.
1132  */
1133
1134 #define AVOID_OLD       1
1135 #define DESPERATION     2
1136
1137 static void init_block_alloc(ext2_resize_t rfs)
1138 {
1139         rfs->alloc_state = AVOID_OLD;
1140         rfs->new_blk = rfs->new_fs->super->s_first_data_block;
1141 #if 0
1142         /* HACK for testing */
1143         if (ext2fs_blocks_count(rfs->new_fs->super) >
1144             ext2fs_blocks_count(rfs->old_fs->super))
1145                 rfs->new_blk = ext2fs_blocks_count(rfs->old_fs->super);
1146 #endif
1147 }
1148
1149 static blk64_t get_new_block(ext2_resize_t rfs)
1150 {
1151         ext2_filsys     fs = rfs->new_fs;
1152
1153         while (1) {
1154                 if (rfs->new_blk >= ext2fs_blocks_count(fs->super)) {
1155                         if (rfs->alloc_state == DESPERATION)
1156                                 return 0;
1157
1158 #ifdef RESIZE2FS_DEBUG
1159                         if (rfs->flags & RESIZE_DEBUG_BMOVE)
1160                                 printf("Going into desperation mode "
1161                                        "for block allocations\n");
1162 #endif
1163                         rfs->alloc_state = DESPERATION;
1164                         rfs->new_blk = fs->super->s_first_data_block;
1165                         continue;
1166                 }
1167                 if (ext2fs_test_block_bitmap2(fs->block_map, rfs->new_blk) ||
1168                     ext2fs_test_block_bitmap2(rfs->reserve_blocks,
1169                                              rfs->new_blk) ||
1170                     ((rfs->alloc_state == AVOID_OLD) &&
1171                      (rfs->new_blk < ext2fs_blocks_count(rfs->old_fs->super)) &&
1172                      ext2fs_test_block_bitmap2(rfs->old_fs->block_map,
1173                                               rfs->new_blk))) {
1174                         rfs->new_blk++;
1175                         continue;
1176                 }
1177                 return rfs->new_blk;
1178         }
1179 }
1180
1181 static errcode_t resize2fs_get_alloc_block(ext2_filsys fs, blk64_t goal,
1182                                            blk64_t *ret)
1183 {
1184         ext2_resize_t rfs = (ext2_resize_t) fs->priv_data;
1185         blk64_t blk;
1186
1187         blk = get_new_block(rfs);
1188         if (!blk)
1189                 return ENOSPC;
1190
1191 #ifdef RESIZE2FS_DEBUG
1192         if (rfs->flags & 0xF)
1193                 printf("get_alloc_block allocating %llu\n", blk);
1194 #endif
1195
1196         ext2fs_mark_block_bitmap2(rfs->old_fs->block_map, blk);
1197         ext2fs_mark_block_bitmap2(rfs->new_fs->block_map, blk);
1198         *ret = (blk64_t) blk;
1199         return 0;
1200 }
1201
1202 static errcode_t block_mover(ext2_resize_t rfs)
1203 {
1204         blk64_t                 blk, old_blk, new_blk;
1205         ext2_filsys             fs = rfs->new_fs;
1206         ext2_filsys             old_fs = rfs->old_fs;
1207         errcode_t               retval;
1208         __u64                   size;
1209         int                     c;
1210         int                     to_move, moved;
1211         ext2_badblocks_list     badblock_list = 0;
1212         int                     bb_modified = 0;
1213
1214         fs->get_alloc_block = resize2fs_get_alloc_block;
1215         old_fs->get_alloc_block = resize2fs_get_alloc_block;
1216
1217         retval = ext2fs_read_bb_inode(old_fs, &badblock_list);
1218         if (retval)
1219                 return retval;
1220
1221         new_blk = fs->super->s_first_data_block;
1222         if (!rfs->itable_buf) {
1223                 retval = ext2fs_get_array(fs->blocksize,
1224                                         fs->inode_blocks_per_group,
1225                                         &rfs->itable_buf);
1226                 if (retval)
1227                         return retval;
1228         }
1229         retval = ext2fs_create_extent_table(&rfs->bmap, 0);
1230         if (retval)
1231                 return retval;
1232
1233         /*
1234          * The first step is to figure out where all of the blocks
1235          * will go.
1236          */
1237         to_move = moved = 0;
1238         init_block_alloc(rfs);
1239         for (blk = B2C(old_fs->super->s_first_data_block);
1240              blk < ext2fs_blocks_count(old_fs->super);
1241              blk += EXT2FS_CLUSTER_RATIO(fs)) {
1242                 if (!ext2fs_test_block_bitmap2(old_fs->block_map, blk))
1243                         continue;
1244                 if (!ext2fs_test_block_bitmap2(rfs->move_blocks, blk))
1245                         continue;
1246                 if (ext2fs_badblocks_list_test(badblock_list, blk)) {
1247                         ext2fs_badblocks_list_del(badblock_list, blk);
1248                         bb_modified++;
1249                         continue;
1250                 }
1251
1252                 new_blk = get_new_block(rfs);
1253                 if (!new_blk) {
1254                         retval = ENOSPC;
1255                         goto errout;
1256                 }
1257                 ext2fs_block_alloc_stats2(fs, new_blk, +1);
1258                 ext2fs_add_extent_entry(rfs->bmap, B2C(blk), B2C(new_blk));
1259                 to_move++;
1260         }
1261
1262         if (to_move == 0) {
1263                 if (rfs->bmap) {
1264                         ext2fs_free_extent_table(rfs->bmap);
1265                         rfs->bmap = 0;
1266                 }
1267                 retval = 0;
1268                 goto errout;
1269         }
1270
1271         /*
1272          * Step two is to actually move the blocks
1273          */
1274         retval =  ext2fs_iterate_extent(rfs->bmap, 0, 0, 0);
1275         if (retval) goto errout;
1276
1277         if (rfs->progress) {
1278                 retval = (rfs->progress)(rfs, E2_RSZ_BLOCK_RELOC_PASS,
1279                                          0, to_move);
1280                 if (retval)
1281                         goto errout;
1282         }
1283         while (1) {
1284                 retval = ext2fs_iterate_extent(rfs->bmap, &old_blk, &new_blk, &size);
1285                 if (retval) goto errout;
1286                 if (!size)
1287                         break;
1288                 old_blk = C2B(old_blk);
1289                 new_blk = C2B(new_blk);
1290                 size = C2B(size);
1291 #ifdef RESIZE2FS_DEBUG
1292                 if (rfs->flags & RESIZE_DEBUG_BMOVE)
1293                         printf("Moving %llu blocks %llu->%llu\n",
1294                                size, old_blk, new_blk);
1295 #endif
1296                 do {
1297                         c = size;
1298                         if (c > fs->inode_blocks_per_group)
1299                                 c = fs->inode_blocks_per_group;
1300                         retval = io_channel_read_blk64(fs->io, old_blk, c,
1301                                                        rfs->itable_buf);
1302                         if (retval) goto errout;
1303                         retval = io_channel_write_blk64(fs->io, new_blk, c,
1304                                                         rfs->itable_buf);
1305                         if (retval) goto errout;
1306                         size -= c;
1307                         new_blk += c;
1308                         old_blk += c;
1309                         moved += c;
1310                         if (rfs->progress) {
1311                                 io_channel_flush(fs->io);
1312                                 retval = (rfs->progress)(rfs,
1313                                                 E2_RSZ_BLOCK_RELOC_PASS,
1314                                                 moved, to_move);
1315                                 if (retval)
1316                                         goto errout;
1317                         }
1318                 } while (size > 0);
1319                 io_channel_flush(fs->io);
1320         }
1321
1322 errout:
1323         if (badblock_list) {
1324                 if (!retval && bb_modified)
1325                         retval = ext2fs_update_bb_inode(old_fs,
1326                                                         badblock_list);
1327                 ext2fs_badblocks_list_free(badblock_list);
1328         }
1329         return retval;
1330 }
1331
1332
1333 /* --------------------------------------------------------------------
1334  *
1335  * Resize processing, phase 3
1336  *
1337  * --------------------------------------------------------------------
1338  */
1339
1340
1341 /*
1342  * The extent translation table is stored in clusters so we need to
1343  * take special care when mapping a source block number to its
1344  * destination block number.
1345  */
1346 __u64 extent_translate(ext2_filsys fs, ext2_extent extent, __u64 old_loc)
1347 {
1348         __u64 new_block = C2B(ext2fs_extent_translate(extent, B2C(old_loc)));
1349
1350         if (new_block != 0)
1351                 new_block += old_loc & (EXT2FS_CLUSTER_RATIO(fs) - 1);
1352         return new_block;
1353 }
1354
1355 struct process_block_struct {
1356         ext2_resize_t           rfs;
1357         ext2_ino_t              ino;
1358         struct ext2_inode *     inode;
1359         errcode_t               error;
1360         int                     is_dir;
1361         int                     changed;
1362 };
1363
1364 static int process_block(ext2_filsys fs, blk64_t        *block_nr,
1365                          e2_blkcnt_t blockcnt,
1366                          blk64_t ref_block EXT2FS_ATTR((unused)),
1367                          int ref_offset EXT2FS_ATTR((unused)), void *priv_data)
1368 {
1369         struct process_block_struct *pb;
1370         errcode_t       retval;
1371         blk64_t         block, new_block;
1372         int             ret = 0;
1373
1374         pb = (struct process_block_struct *) priv_data;
1375         block = *block_nr;
1376         if (pb->rfs->bmap) {
1377                 new_block = extent_translate(fs, pb->rfs->bmap, block);
1378                 if (new_block) {
1379                         *block_nr = new_block;
1380                         ret |= BLOCK_CHANGED;
1381                         pb->changed = 1;
1382 #ifdef RESIZE2FS_DEBUG
1383                         if (pb->rfs->flags & RESIZE_DEBUG_BMOVE)
1384                                 printf("ino=%u, blockcnt=%lld, %llu->%llu\n",
1385                                        pb->ino, blockcnt, block, new_block);
1386 #endif
1387                         block = new_block;
1388                 }
1389         }
1390         if (pb->is_dir) {
1391                 retval = ext2fs_add_dir_block2(fs->dblist, pb->ino,
1392                                                block, (int) blockcnt);
1393                 if (retval) {
1394                         pb->error = retval;
1395                         ret |= BLOCK_ABORT;
1396                 }
1397         }
1398         return ret;
1399 }
1400
1401 /*
1402  * Progress callback
1403  */
1404 static errcode_t progress_callback(ext2_filsys fs,
1405                                    ext2_inode_scan scan EXT2FS_ATTR((unused)),
1406                                    dgrp_t group, void * priv_data)
1407 {
1408         ext2_resize_t rfs = (ext2_resize_t) priv_data;
1409         errcode_t               retval;
1410
1411         /*
1412          * This check is to protect against old ext2 libraries.  It
1413          * shouldn't be needed against new libraries.
1414          */
1415         if ((group+1) == 0)
1416                 return 0;
1417
1418         if (rfs->progress) {
1419                 io_channel_flush(fs->io);
1420                 retval = (rfs->progress)(rfs, E2_RSZ_INODE_SCAN_PASS,
1421                                          group+1, fs->group_desc_count);
1422                 if (retval)
1423                         return retval;
1424         }
1425
1426         return 0;
1427 }
1428
1429 static errcode_t inode_scan_and_fix(ext2_resize_t rfs)
1430 {
1431         struct process_block_struct     pb;
1432         ext2_ino_t              ino, new_inode;
1433         struct ext2_inode       *inode = NULL;
1434         ext2_inode_scan         scan = NULL;
1435         errcode_t               retval;
1436         char                    *block_buf = 0;
1437         ext2_ino_t              start_to_move;
1438         blk64_t                 orig_size;
1439         blk64_t                 new_block;
1440         int                     inode_size;
1441
1442         if ((rfs->old_fs->group_desc_count <=
1443              rfs->new_fs->group_desc_count) &&
1444             !rfs->bmap)
1445                 return 0;
1446
1447         /*
1448          * Save the original size of the old filesystem, and
1449          * temporarily set the size to be the new size if the new size
1450          * is larger.  We need to do this to avoid catching an error
1451          * by the block iterator routines
1452          */
1453         orig_size = ext2fs_blocks_count(rfs->old_fs->super);
1454         if (orig_size < ext2fs_blocks_count(rfs->new_fs->super))
1455                 ext2fs_blocks_count_set(rfs->old_fs->super,
1456                                 ext2fs_blocks_count(rfs->new_fs->super));
1457
1458         retval = ext2fs_open_inode_scan(rfs->old_fs, 0, &scan);
1459         if (retval) goto errout;
1460
1461         retval = ext2fs_init_dblist(rfs->old_fs, 0);
1462         if (retval) goto errout;
1463         retval = ext2fs_get_array(rfs->old_fs->blocksize, 3, &block_buf);
1464         if (retval) goto errout;
1465
1466         start_to_move = (rfs->new_fs->group_desc_count *
1467                          rfs->new_fs->super->s_inodes_per_group);
1468
1469         if (rfs->progress) {
1470                 retval = (rfs->progress)(rfs, E2_RSZ_INODE_SCAN_PASS,
1471                                          0, rfs->old_fs->group_desc_count);
1472                 if (retval)
1473                         goto errout;
1474         }
1475         ext2fs_set_inode_callback(scan, progress_callback, (void *) rfs);
1476         pb.rfs = rfs;
1477         pb.inode = inode;
1478         pb.error = 0;
1479         new_inode = EXT2_FIRST_INODE(rfs->new_fs->super);
1480         inode_size = EXT2_INODE_SIZE(rfs->new_fs->super);
1481         inode = malloc(inode_size);
1482         if (!inode) {
1483                 retval = ENOMEM;
1484                 goto errout;
1485         }
1486         /*
1487          * First, copy all of the inodes that need to be moved
1488          * elsewhere in the inode table
1489          */
1490         while (1) {
1491                 retval = ext2fs_get_next_inode_full(scan, &ino, inode, inode_size);
1492                 if (retval) goto errout;
1493                 if (!ino)
1494                         break;
1495
1496                 if (inode->i_links_count == 0 && ino != EXT2_RESIZE_INO)
1497                         continue; /* inode not in use */
1498
1499                 pb.is_dir = LINUX_S_ISDIR(inode->i_mode);
1500                 pb.changed = 0;
1501
1502                 if (ext2fs_file_acl_block(rfs->old_fs, inode) && rfs->bmap) {
1503                         new_block = extent_translate(rfs->old_fs, rfs->bmap,
1504                                 ext2fs_file_acl_block(rfs->old_fs, inode));
1505                         if (new_block) {
1506                                 ext2fs_file_acl_block_set(rfs->old_fs, inode,
1507                                                           new_block);
1508                                 retval = ext2fs_write_inode_full(rfs->old_fs,
1509                                                             ino, inode, inode_size);
1510                                 if (retval) goto errout;
1511                         }
1512                 }
1513
1514                 if (ext2fs_inode_has_valid_blocks2(rfs->old_fs, inode) &&
1515                     (rfs->bmap || pb.is_dir)) {
1516                         pb.ino = ino;
1517                         retval = ext2fs_block_iterate3(rfs->old_fs,
1518                                                        ino, 0, block_buf,
1519                                                        process_block, &pb);
1520                         if (retval)
1521                                 goto errout;
1522                         if (pb.error) {
1523                                 retval = pb.error;
1524                                 goto errout;
1525                         }
1526                 }
1527
1528                 if (ino <= start_to_move)
1529                         continue; /* Don't need to move it. */
1530
1531                 /*
1532                  * Find a new inode
1533                  */
1534                 retval = ext2fs_new_inode(rfs->new_fs, 0, 0, 0, &new_inode);
1535                 if (retval)
1536                         goto errout;
1537
1538                 ext2fs_inode_alloc_stats2(rfs->new_fs, new_inode, +1,
1539                                           pb.is_dir);
1540                 if (pb.changed) {
1541                         /* Get the new version of the inode */
1542                         retval = ext2fs_read_inode_full(rfs->old_fs, ino,
1543                                                 inode, inode_size);
1544                         if (retval) goto errout;
1545                 }
1546                 inode->i_ctime = time(0);
1547                 retval = ext2fs_write_inode_full(rfs->old_fs, new_inode,
1548                                                 inode, inode_size);
1549                 if (retval) goto errout;
1550
1551 #ifdef RESIZE2FS_DEBUG
1552                 if (rfs->flags & RESIZE_DEBUG_INODEMAP)
1553                         printf("Inode moved %u->%u\n", ino, new_inode);
1554 #endif
1555                 if (!rfs->imap) {
1556                         retval = ext2fs_create_extent_table(&rfs->imap, 0);
1557                         if (retval)
1558                                 goto errout;
1559                 }
1560                 ext2fs_add_extent_entry(rfs->imap, ino, new_inode);
1561         }
1562         io_channel_flush(rfs->old_fs->io);
1563
1564 errout:
1565         ext2fs_blocks_count_set(rfs->old_fs->super, orig_size);
1566         if (rfs->bmap) {
1567                 ext2fs_free_extent_table(rfs->bmap);
1568                 rfs->bmap = 0;
1569         }
1570         if (scan)
1571                 ext2fs_close_inode_scan(scan);
1572         if (block_buf)
1573                 ext2fs_free_mem(&block_buf);
1574         free(inode);
1575         return retval;
1576 }
1577
1578 /* --------------------------------------------------------------------
1579  *
1580  * Resize processing, phase 4.
1581  *
1582  * --------------------------------------------------------------------
1583  */
1584
1585 struct istruct {
1586         ext2_resize_t rfs;
1587         errcode_t       err;
1588         unsigned int    max_dirs;
1589         unsigned int    num;
1590 };
1591
1592 static int check_and_change_inodes(ext2_ino_t dir,
1593                                    int entry EXT2FS_ATTR((unused)),
1594                                    struct ext2_dir_entry *dirent, int offset,
1595                                    int  blocksize EXT2FS_ATTR((unused)),
1596                                    char *buf EXT2FS_ATTR((unused)),
1597                                    void *priv_data)
1598 {
1599         struct istruct *is = (struct istruct *) priv_data;
1600         struct ext2_inode       inode;
1601         ext2_ino_t              new_inode;
1602         errcode_t               retval;
1603
1604         if (is->rfs->progress && offset == 0) {
1605                 io_channel_flush(is->rfs->old_fs->io);
1606                 is->err = (is->rfs->progress)(is->rfs,
1607                                               E2_RSZ_INODE_REF_UPD_PASS,
1608                                               ++is->num, is->max_dirs);
1609                 if (is->err)
1610                         return DIRENT_ABORT;
1611         }
1612
1613         if (!dirent->inode)
1614                 return 0;
1615
1616         new_inode = ext2fs_extent_translate(is->rfs->imap, dirent->inode);
1617
1618         if (!new_inode)
1619                 return 0;
1620 #ifdef RESIZE2FS_DEBUG
1621         if (is->rfs->flags & RESIZE_DEBUG_INODEMAP)
1622                 printf("Inode translate (dir=%u, name=%.*s, %u->%u)\n",
1623                        dir, dirent->name_len&0xFF, dirent->name,
1624                        dirent->inode, new_inode);
1625 #endif
1626
1627         dirent->inode = new_inode;
1628
1629         /* Update the directory mtime and ctime */
1630         retval = ext2fs_read_inode(is->rfs->old_fs, dir, &inode);
1631         if (retval == 0) {
1632                 inode.i_mtime = inode.i_ctime = time(0);
1633                 is->err = ext2fs_write_inode(is->rfs->old_fs, dir, &inode);
1634                 if (is->err)
1635                         return DIRENT_ABORT;
1636         }
1637
1638         return DIRENT_CHANGED;
1639 }
1640
1641 static errcode_t inode_ref_fix(ext2_resize_t rfs)
1642 {
1643         errcode_t               retval;
1644         struct istruct          is;
1645
1646         if (!rfs->imap)
1647                 return 0;
1648
1649         /*
1650          * Now, we iterate over all of the directories to update the
1651          * inode references
1652          */
1653         is.num = 0;
1654         is.max_dirs = ext2fs_dblist_count2(rfs->old_fs->dblist);
1655         is.rfs = rfs;
1656         is.err = 0;
1657
1658         if (rfs->progress) {
1659                 retval = (rfs->progress)(rfs, E2_RSZ_INODE_REF_UPD_PASS,
1660                                          0, is.max_dirs);
1661                 if (retval)
1662                         goto errout;
1663         }
1664
1665         retval = ext2fs_dblist_dir_iterate(rfs->old_fs->dblist,
1666                                            DIRENT_FLAG_INCLUDE_EMPTY, 0,
1667                                            check_and_change_inodes, &is);
1668         if (retval)
1669                 goto errout;
1670         if (is.err) {
1671                 retval = is.err;
1672                 goto errout;
1673         }
1674
1675         if (rfs->progress && (is.num < is.max_dirs))
1676                 (rfs->progress)(rfs, E2_RSZ_INODE_REF_UPD_PASS,
1677                                 is.max_dirs, is.max_dirs);
1678
1679 errout:
1680         ext2fs_free_extent_table(rfs->imap);
1681         rfs->imap = 0;
1682         return retval;
1683 }
1684
1685
1686 /* --------------------------------------------------------------------
1687  *
1688  * Resize processing, phase 5.
1689  *
1690  * In this phase we actually move the inode table around, and then
1691  * update the summary statistics.  This is scary, since aborting here
1692  * will potentially scramble the filesystem.  (We are moving the
1693  * inode tables around in place, and so the potential for lost data,
1694  * or at the very least scrambling the mapping between filenames and
1695  * inode numbers is very high in case of a power failure here.)
1696  * --------------------------------------------------------------------
1697  */
1698
1699
1700 /*
1701  * A very scary routine --- this one moves the inode table around!!!
1702  *
1703  * After this you have to use the rfs->new_fs file handle to read and
1704  * write inodes.
1705  */
1706 static errcode_t move_itables(ext2_resize_t rfs)
1707 {
1708         int             n, num, size;
1709         long long       diff;
1710         dgrp_t          i, max_groups;
1711         ext2_filsys     fs = rfs->new_fs;
1712         char            *cp;
1713         blk64_t         old_blk, new_blk, blk;
1714         errcode_t       retval;
1715         int             j, to_move, moved;
1716
1717         max_groups = fs->group_desc_count;
1718         if (max_groups > rfs->old_fs->group_desc_count)
1719                 max_groups = rfs->old_fs->group_desc_count;
1720
1721         size = fs->blocksize * fs->inode_blocks_per_group;
1722         if (!rfs->itable_buf) {
1723                 retval = ext2fs_get_mem(size, &rfs->itable_buf);
1724                 if (retval)
1725                         return retval;
1726         }
1727
1728         /*
1729          * Figure out how many inode tables we need to move
1730          */
1731         to_move = moved = 0;
1732         for (i=0; i < max_groups; i++)
1733                 if (ext2fs_inode_table_loc(rfs->old_fs, i) !=
1734                     ext2fs_inode_table_loc(fs, i))
1735                         to_move++;
1736
1737         if (to_move == 0)
1738                 return 0;
1739
1740         if (rfs->progress) {
1741                 retval = rfs->progress(rfs, E2_RSZ_MOVE_ITABLE_PASS,
1742                                        0, to_move);
1743                 if (retval)
1744                         goto errout;
1745         }
1746
1747         rfs->old_fs->flags |= EXT2_FLAG_MASTER_SB_ONLY;
1748
1749         for (i=0; i < max_groups; i++) {
1750                 old_blk = ext2fs_inode_table_loc(rfs->old_fs, i);
1751                 new_blk = ext2fs_inode_table_loc(fs, i);
1752                 diff = new_blk - old_blk;
1753
1754 #ifdef RESIZE2FS_DEBUG
1755                 if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
1756                         printf("Itable move group %d block %llu->%llu (diff %lld)\n",
1757                                i, old_blk, new_blk, diff);
1758 #endif
1759
1760                 if (!diff)
1761                         continue;
1762
1763                 retval = io_channel_read_blk64(fs->io, old_blk,
1764                                                fs->inode_blocks_per_group,
1765                                                rfs->itable_buf);
1766                 if (retval)
1767                         goto errout;
1768                 /*
1769                  * The end of the inode table segment often contains
1770                  * all zeros, and we're often only moving the inode
1771                  * table down a block or two.  If so, we can optimize
1772                  * things by not rewriting blocks that we know to be zero
1773                  * already.
1774                  */
1775                 for (cp = rfs->itable_buf+size-1, n=0; n < size; n++, cp--)
1776                         if (*cp)
1777                                 break;
1778                 n = n >> EXT2_BLOCK_SIZE_BITS(fs->super);
1779 #ifdef RESIZE2FS_DEBUG
1780                 if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
1781                         printf("%d blocks of zeros...\n", n);
1782 #endif
1783                 num = fs->inode_blocks_per_group;
1784                 if (n > diff)
1785                         num -= n;
1786
1787                 retval = io_channel_write_blk64(fs->io, new_blk,
1788                                                 num, rfs->itable_buf);
1789                 if (retval) {
1790                         io_channel_write_blk64(fs->io, old_blk,
1791                                                num, rfs->itable_buf);
1792                         goto errout;
1793                 }
1794                 if (n > diff) {
1795                         retval = io_channel_write_blk64(fs->io,
1796                               old_blk + fs->inode_blocks_per_group,
1797                               diff, (rfs->itable_buf +
1798                                      (fs->inode_blocks_per_group - diff) *
1799                                      fs->blocksize));
1800                         if (retval)
1801                                 goto errout;
1802                 }
1803
1804                 for (blk = ext2fs_inode_table_loc(rfs->old_fs, i), j=0;
1805                      j < fs->inode_blocks_per_group ; j++, blk++)
1806                         ext2fs_block_alloc_stats2(fs, blk, -1);
1807
1808                 ext2fs_inode_table_loc_set(rfs->old_fs, i, new_blk);
1809                 ext2fs_group_desc_csum_set(rfs->old_fs, i);
1810                 ext2fs_mark_super_dirty(rfs->old_fs);
1811                 ext2fs_flush(rfs->old_fs);
1812
1813                 if (rfs->progress) {
1814                         retval = rfs->progress(rfs, E2_RSZ_MOVE_ITABLE_PASS,
1815                                                ++moved, to_move);
1816                         if (retval)
1817                                 goto errout;
1818                 }
1819         }
1820         mark_table_blocks(fs, fs->block_map);
1821         ext2fs_flush(fs);
1822 #ifdef RESIZE2FS_DEBUG
1823         if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
1824                 printf("Inode table move finished.\n");
1825 #endif
1826         return 0;
1827
1828 errout:
1829         return retval;
1830 }
1831
1832 /*
1833  * Fix the resize inode
1834  */
1835 static errcode_t fix_resize_inode(ext2_filsys fs)
1836 {
1837         struct ext2_inode       inode;
1838         errcode_t               retval;
1839         char                    *block_buf = NULL;
1840
1841         if (!(fs->super->s_feature_compat &
1842               EXT2_FEATURE_COMPAT_RESIZE_INODE))
1843                 return 0;
1844
1845         retval = ext2fs_get_mem(fs->blocksize, &block_buf);
1846         if (retval) goto errout;
1847
1848         retval = ext2fs_read_inode(fs, EXT2_RESIZE_INO, &inode);
1849         if (retval) goto errout;
1850
1851         ext2fs_iblk_set(fs, &inode, 1);
1852
1853         retval = ext2fs_write_inode(fs, EXT2_RESIZE_INO, &inode);
1854         if (retval) goto errout;
1855
1856         if (!inode.i_block[EXT2_DIND_BLOCK]) {
1857                 /*
1858                  * Avoid zeroing out block #0; that's rude.  This
1859                  * should never happen anyway since the filesystem
1860                  * should be fsck'ed and we assume it is consistent.
1861                  */
1862                 fprintf(stderr,
1863                         _("Should never happen: resize inode corrupt!\n"));
1864                 exit(1);
1865         }
1866
1867         memset(block_buf, 0, fs->blocksize);
1868
1869         retval = io_channel_write_blk64(fs->io, inode.i_block[EXT2_DIND_BLOCK],
1870                                         1, block_buf);
1871         if (retval) goto errout;
1872
1873         retval = ext2fs_create_resize_inode(fs);
1874         if (retval)
1875                 goto errout;
1876
1877 errout:
1878         if (block_buf)
1879                 ext2fs_free_mem(&block_buf);
1880         return retval;
1881 }
1882
1883 /*
1884  * Finally, recalculate the summary information
1885  */
1886 static errcode_t ext2fs_calculate_summary_stats(ext2_filsys fs)
1887 {
1888         blk64_t         blk;
1889         ext2_ino_t      ino;
1890         unsigned int    group = 0;
1891         unsigned int    count = 0;
1892         blk64_t         total_blocks_free = 0;
1893         int             total_inodes_free = 0;
1894         int             group_free = 0;
1895         int             uninit = 0;
1896         blk64_t         super_blk, old_desc_blk, new_desc_blk;
1897         int             old_desc_blocks;
1898
1899         /*
1900          * First calculate the block statistics
1901          */
1902         uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_BLOCK_UNINIT);
1903         ext2fs_super_and_bgd_loc2(fs, group, &super_blk, &old_desc_blk,
1904                                   &new_desc_blk, 0);
1905         if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
1906                 old_desc_blocks = fs->super->s_first_meta_bg;
1907         else
1908                 old_desc_blocks = fs->desc_blocks +
1909                         fs->super->s_reserved_gdt_blocks;
1910         for (blk = B2C(fs->super->s_first_data_block);
1911              blk < ext2fs_blocks_count(fs->super);
1912              blk += EXT2FS_CLUSTER_RATIO(fs)) {
1913                 if ((uninit &&
1914                      !(EQ_CLSTR(blk, super_blk) ||
1915                        ((old_desc_blk && old_desc_blocks &&
1916                          GE_CLSTR(blk, old_desc_blk) &&
1917                          LT_CLSTR(blk, old_desc_blk + old_desc_blocks))) ||
1918                        ((new_desc_blk && EQ_CLSTR(blk, new_desc_blk))) ||
1919                        EQ_CLSTR(blk, ext2fs_block_bitmap_loc(fs, group)) ||
1920                        EQ_CLSTR(blk, ext2fs_inode_bitmap_loc(fs, group)) ||
1921                        ((GE_CLSTR(blk, ext2fs_inode_table_loc(fs, group)) &&
1922                          LT_CLSTR(blk, ext2fs_inode_table_loc(fs, group)
1923                                   + fs->inode_blocks_per_group))))) ||
1924                     (!ext2fs_fast_test_block_bitmap2(fs->block_map, blk))) {
1925                         group_free++;
1926                         total_blocks_free++;
1927                 }
1928                 count++;
1929                 if ((count == fs->super->s_clusters_per_group) ||
1930                     EQ_CLSTR(blk, ext2fs_blocks_count(fs->super)-1)) {
1931                         ext2fs_bg_free_blocks_count_set(fs, group, group_free);
1932                         ext2fs_group_desc_csum_set(fs, group);
1933                         group++;
1934                         if (group >= fs->group_desc_count)
1935                                 break;
1936                         count = 0;
1937                         group_free = 0;
1938                         uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_BLOCK_UNINIT);
1939                         ext2fs_super_and_bgd_loc2(fs, group, &super_blk,
1940                                                   &old_desc_blk,
1941                                                   &new_desc_blk, 0);
1942                         if (fs->super->s_feature_incompat &
1943                             EXT2_FEATURE_INCOMPAT_META_BG)
1944                                 old_desc_blocks = fs->super->s_first_meta_bg;
1945                         else
1946                                 old_desc_blocks = fs->desc_blocks +
1947                                         fs->super->s_reserved_gdt_blocks;
1948                 }
1949         }
1950         total_blocks_free = C2B(total_blocks_free);
1951         ext2fs_free_blocks_count_set(fs->super, total_blocks_free);
1952
1953         /*
1954          * Next, calculate the inode statistics
1955          */
1956         group_free = 0;
1957         count = 0;
1958         group = 0;
1959
1960         /* Protect loop from wrap-around if s_inodes_count maxed */
1961         uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_INODE_UNINIT);
1962         for (ino = 1; ino <= fs->super->s_inodes_count && ino > 0; ino++) {
1963                 if (uninit ||
1964                     !ext2fs_fast_test_inode_bitmap2(fs->inode_map, ino)) {
1965                         group_free++;
1966                         total_inodes_free++;
1967                 }
1968                 count++;
1969                 if ((count == fs->super->s_inodes_per_group) ||
1970                     (ino == fs->super->s_inodes_count)) {
1971                         ext2fs_bg_free_inodes_count_set(fs, group, group_free);
1972                         ext2fs_group_desc_csum_set(fs, group);
1973                         group++;
1974                         if (group >= fs->group_desc_count)
1975                                 break;
1976                         count = 0;
1977                         group_free = 0;
1978                         uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_INODE_UNINIT);
1979                 }
1980         }
1981         fs->super->s_free_inodes_count = total_inodes_free;
1982         ext2fs_mark_super_dirty(fs);
1983         return 0;
1984 }
1985
1986 /*
1987  *  Journal may have been relocated; update the backup journal blocks
1988  *  in the superblock.
1989  */
1990 static errcode_t fix_sb_journal_backup(ext2_filsys fs)
1991 {
1992         errcode_t         retval;
1993         struct ext2_inode inode;
1994
1995         if (!(fs->super->s_feature_compat & EXT3_FEATURE_COMPAT_HAS_JOURNAL))
1996                 return 0;
1997
1998         /* External journal? Nothing to do. */
1999         if (fs->super->s_journal_dev && !fs->super->s_journal_inum)
2000                 return 0;
2001
2002         retval = ext2fs_read_inode(fs, fs->super->s_journal_inum, &inode);
2003         if (retval)
2004                 return retval;
2005         memcpy(fs->super->s_jnl_blocks, inode.i_block, EXT2_N_BLOCKS*4);
2006         fs->super->s_jnl_blocks[15] = inode.i_size_high;
2007         fs->super->s_jnl_blocks[16] = inode.i_size;
2008         fs->super->s_jnl_backup_type = EXT3_JNL_BACKUP_BLOCKS;
2009         ext2fs_mark_super_dirty(fs);
2010         return 0;
2011 }
2012
2013 static int calc_group_overhead(ext2_filsys fs, blk64_t grp,
2014                                int old_desc_blocks)
2015 {
2016         blk64_t super_blk, old_desc_blk, new_desc_blk;
2017         int overhead;
2018
2019         /* inode table blocks plus allocation bitmaps */
2020         overhead = fs->inode_blocks_per_group + 2;
2021
2022         ext2fs_super_and_bgd_loc2(fs, grp, &super_blk,
2023                                   &old_desc_blk, &new_desc_blk, 0);
2024         if ((grp == 0) || super_blk)
2025                 overhead++;
2026         if (old_desc_blk)
2027                 overhead += old_desc_blocks;
2028         else if (new_desc_blk)
2029                 overhead++;
2030         return overhead;
2031 }
2032
2033
2034 /*
2035  * calcluate the minimum number of blocks the given fs can be resized to
2036  */
2037 blk64_t calculate_minimum_resize_size(ext2_filsys fs, int flags)
2038 {
2039         ext2_ino_t inode_count;
2040         dgrp_t groups;
2041         blk64_t blks_needed, data_blocks;
2042         blk64_t grp, data_needed, last_start;
2043         blk64_t overhead = 0;
2044         int old_desc_blocks;
2045         int extra_groups = 0;
2046         int flexbg_size = 1 << fs->super->s_log_groups_per_flex;
2047
2048         /*
2049          * first figure out how many group descriptors we need to
2050          * handle the number of inodes we have
2051          */
2052         inode_count = fs->super->s_inodes_count -
2053                 fs->super->s_free_inodes_count;
2054         blks_needed = ext2fs_div_ceil(inode_count,
2055                                       fs->super->s_inodes_per_group) *
2056                 EXT2_BLOCKS_PER_GROUP(fs->super);
2057         groups = ext2fs_div64_ceil(blks_needed,
2058                                    EXT2_BLOCKS_PER_GROUP(fs->super));
2059 #ifdef RESIZE2FS_DEBUG
2060         if (flags & RESIZE_DEBUG_MIN_CALC)
2061                 printf("fs has %d inodes, %d groups required.\n",
2062                        inode_count, groups);
2063 #endif
2064
2065         /*
2066          * number of old-style block group descriptor blocks
2067          */
2068         if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
2069                 old_desc_blocks = fs->super->s_first_meta_bg;
2070         else
2071                 old_desc_blocks = fs->desc_blocks +
2072                         fs->super->s_reserved_gdt_blocks;
2073
2074         /* calculate how many blocks are needed for data */
2075         data_needed = ext2fs_blocks_count(fs->super) -
2076                 ext2fs_free_blocks_count(fs->super);
2077
2078         for (grp = 0; grp < fs->group_desc_count; grp++)
2079                 data_needed -= calc_group_overhead(fs, grp, old_desc_blocks);
2080 #ifdef RESIZE2FS_DEBUG
2081         if (flags & RESIZE_DEBUG_MIN_CALC)
2082                 printf("fs requires %llu data blocks.\n", data_needed);
2083 #endif
2084
2085         /*
2086          * For ext4 we need to allow for up to a flex_bg worth of
2087          * inode tables of slack space so the resize operation can be
2088          * guaranteed to finish.
2089          */
2090         if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_FLEX_BG) {
2091                 extra_groups = flexbg_size - (groups & (flexbg_size - 1));
2092                 data_needed += fs->inode_blocks_per_group * extra_groups;
2093                 extra_groups = groups % flexbg_size;
2094         }
2095
2096         /*
2097          * figure out how many data blocks we have given the number of groups
2098          * we need for our inodes
2099          */
2100         data_blocks = groups * EXT2_BLOCKS_PER_GROUP(fs->super);
2101         last_start = 0;
2102         for (grp = 0; grp < groups; grp++) {
2103                 overhead = calc_group_overhead(fs, grp, old_desc_blocks);
2104
2105                 /*
2106                  * we want to keep track of how much data we can store in
2107                  * the groups leading up to the last group so we can determine
2108                  * how big the last group needs to be
2109                  */
2110                 if (grp != (groups - 1))
2111                         last_start += EXT2_BLOCKS_PER_GROUP(fs->super) -
2112                                 overhead;
2113
2114                 data_blocks -= overhead;
2115         }
2116 #ifdef RESIZE2FS_DEBUG
2117         if (flags & RESIZE_DEBUG_MIN_CALC)
2118                 printf("With %d group(s), we have %llu blocks available.\n",
2119                        groups, data_blocks);
2120 #endif
2121
2122         /*
2123          * if we need more group descriptors in order to accomodate our data
2124          * then we need to add them here
2125          */
2126         while (data_needed > data_blocks) {
2127                 blk64_t remainder = data_needed - data_blocks;
2128                 dgrp_t extra_grps;
2129
2130                 /* figure out how many more groups we need for the data */
2131                 extra_grps = ext2fs_div64_ceil(remainder,
2132                                                EXT2_BLOCKS_PER_GROUP(fs->super));
2133
2134                 data_blocks += extra_grps * EXT2_BLOCKS_PER_GROUP(fs->super);
2135
2136                 /* ok we have to account for the last group */
2137                 overhead = calc_group_overhead(fs, groups-1, old_desc_blocks);
2138                 last_start += EXT2_BLOCKS_PER_GROUP(fs->super) - overhead;
2139
2140                 for (grp = groups; grp < groups+extra_grps; grp++) {
2141                         overhead = calc_group_overhead(fs, grp,
2142                                                        old_desc_blocks);
2143
2144                         /*
2145                          * again, we need to see how much data we cram into
2146                          * all of the groups leading up to the last group
2147                          */
2148                         if (grp != (groups + extra_grps - 1))
2149                                 last_start += EXT2_BLOCKS_PER_GROUP(fs->super)
2150                                         - overhead;
2151
2152                         data_blocks -= overhead;
2153                 }
2154
2155                 groups += extra_grps;
2156                 extra_groups += extra_grps;
2157                 if (fs->super->s_feature_incompat
2158                         & EXT4_FEATURE_INCOMPAT_FLEX_BG
2159                     && extra_groups > flexbg_size) {
2160                         /*
2161                          * For ext4 we need to allow for up to a flex_bg worth
2162                          * of inode tables of slack space so the resize
2163                          * operation can be guaranteed to finish.
2164                          */
2165                         extra_groups = flexbg_size -
2166                                                 (groups & (flexbg_size - 1));
2167                         data_needed += (fs->inode_blocks_per_group *
2168                                         extra_groups);
2169                         extra_groups = groups % flexbg_size;
2170                 }
2171 #ifdef RESIZE2FS_DEBUG
2172                 if (flags & RESIZE_DEBUG_MIN_CALC)
2173                         printf("Added %d extra group(s), "
2174                                "data_needed %llu, data_blocks %llu, "
2175                                "last_start %llu\n",
2176                                extra_grps, data_needed, data_blocks,
2177                                last_start);
2178 #endif
2179         }
2180
2181         /* now for the fun voodoo */
2182         overhead = calc_group_overhead(fs, groups-1, old_desc_blocks);
2183 #ifdef RESIZE2FS_DEBUG
2184         if (flags & RESIZE_DEBUG_MIN_CALC)
2185                 printf("Last group's overhead is %llu\n", overhead);
2186 #endif
2187
2188         /*
2189          * if this is the case then the last group is going to have data in it
2190          * so we need to adjust the size of the last group accordingly
2191          */
2192         if (last_start < data_needed) {
2193                 blk64_t remainder = data_needed - last_start;
2194
2195 #ifdef RESIZE2FS_DEBUG
2196                 if (flags & RESIZE_DEBUG_MIN_CALC)
2197                         printf("Need %llu data blocks in last group\n",
2198                                remainder);
2199 #endif
2200                 /*
2201                  * 50 is a magic number that mkfs/resize uses to see if its
2202                  * even worth making/resizing the fs.  basically you need to
2203                  * have at least 50 blocks in addition to the blocks needed
2204                  * for the metadata in the last group
2205                  */
2206                 if (remainder > 50)
2207                         overhead += remainder;
2208                 else
2209                         overhead += 50;
2210         } else
2211                 overhead += 50;
2212
2213         overhead += fs->super->s_first_data_block;
2214 #ifdef RESIZE2FS_DEBUG
2215         if (flags & RESIZE_DEBUG_MIN_CALC)
2216                 printf("Final size of last group is %lld\n", overhead);
2217 #endif
2218
2219         /*
2220          * since our last group doesn't have to be BLOCKS_PER_GROUP large, we
2221          * only do groups-1, and then add the number of blocks needed to
2222          * handle the group descriptor metadata+data that we need
2223          */
2224         blks_needed = (groups-1) * EXT2_BLOCKS_PER_GROUP(fs->super);
2225         blks_needed += overhead;
2226
2227 #ifdef RESIZE2FS_DEBUG
2228         if (flags & RESIZE_DEBUG_MIN_CALC)
2229                 printf("Estimated blocks needed: %llu\n", blks_needed);
2230 #endif
2231
2232         /*
2233          * If at this point we've already added up more "needed" than
2234          * the current size, just return current size as minimum.
2235          */
2236         if (blks_needed >= ext2fs_blocks_count(fs->super))
2237                 return ext2fs_blocks_count(fs->super);
2238         /*
2239          * We need to reserve a few extra blocks if extents are
2240          * enabled, in case we need to grow the extent tree.  The more
2241          * we shrink the file system, the more space we need.
2242          */
2243         if (fs->super->s_feature_incompat & EXT3_FEATURE_INCOMPAT_EXTENTS) {
2244                 blk64_t safe_margin = (ext2fs_blocks_count(fs->super) -
2245                                        blks_needed)/500;
2246 #ifdef RESIZE2FS_DEBUG
2247                 if (flags & RESIZE_DEBUG_MIN_CALC)
2248                         printf("Extents safety margin: %llu\n", safe_margin);
2249 #endif
2250                 blks_needed += safe_margin;
2251         }
2252
2253         return blks_needed;
2254 }