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
 888          * group's metadata blocks (either allocation bitmaps or the
 889          * inode table) which are beyond the end of the new
 890          * filesystem.
 891          */
 892         new_size = ext2fs_blocks_count(fs->super);
 893         if (new_size < ext2fs_blocks_count(old_fs->super)) {
 894                 for (g = 0; g < fs->group_desc_count; g++) {
 895                         int realloc = 0;
 896                         /*
 897                          * ext2fs_allocate_group_table will re-allocate any
 898                          * metadata blocks whose location is set to zero.
 899                          */
 900                         if (ext2fs_block_bitmap_loc(fs, g) >= new_size) {
 901                                 ext2fs_block_bitmap_loc_set(fs, g, 0);
 902                                 realloc = 1;
 903                         }
 904                         if (ext2fs_inode_bitmap_loc(fs, g) >= new_size) {
 905                                 ext2fs_inode_bitmap_loc_set(fs, g, 0);
 906                                 realloc = 1;
 907                         }
 908                         if ((ext2fs_inode_table_loc(fs, g) +
 909                              fs->inode_blocks_per_group) > new_size) {
 910                                 ext2fs_inode_table_loc_set(fs, g, 0);
 911                                 realloc = 1;
 912                         }
 913
 914                         if (realloc) {
 915                                 retval = ext2fs_allocate_group_table(fs, g, 0);
 916                                 if (retval)
 917                                         return retval;
 918                         }
 919                 }
 920         }
 921
 922         /*
 923          * If we're shrinking the filesystem, we need to move all of
 924          * the blocks that don't fit any more
 925          */
 926         for (blk = ext2fs_blocks_count(fs->super);
 927              blk < ext2fs_blocks_count(old_fs->super); blk++) {
 928                 g = ext2fs_group_of_blk2(fs, blk);
 929                 if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
 930                                                EXT4_FEATURE_RO_COMPAT_GDT_CSUM) &&
 931                     ext2fs_bg_flags_test(old_fs, g, EXT2_BG_BLOCK_UNINIT)) {
 932                         /*
 933                          * The block bitmap is uninitialized, so skip
 934                          * to the next block group.
 935                          */
 936                         blk = ext2fs_group_first_block2(fs, g+1) - 1;
 937                         continue;
 938                 }
 939                 if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
 940                     !ext2fs_test_block_bitmap2(meta_bmap, blk)) {
 941                         ext2fs_mark_block_bitmap2(rfs->move_blocks, blk);
 942                         rfs->needed_blocks++;
 943                 }
 944                 ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
 945         }
 946
 947         if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG) {
 948                 old_blocks = old_fs->super->s_first_meta_bg;
 949                 new_blocks = fs->super->s_first_meta_bg;
 950         } else {
 951                 old_blocks = old_fs->desc_blocks + old_fs->super->s_reserved_gdt_blocks;
 952                 new_blocks = fs->desc_blocks + fs->super->s_reserved_gdt_blocks;
 953         }
 954
 955         if (old_blocks == new_blocks) {
 956                 retval = 0;
 957                 goto errout;
 958         }
 959
 960         max_groups = fs->group_desc_count;
 961         if (max_groups > old_fs->group_desc_count)
 962                 max_groups = old_fs->group_desc_count;
 963         group_blk = old_fs->super->s_first_data_block;
 964         /*
 965          * If we're reducing the number of descriptor blocks, this
 966          * makes life easy.  :-)   We just have to mark some extra
 967          * blocks as free.
 968          */
 969         if (old_blocks > new_blocks) {
 970                 for (i = 0; i < max_groups; i++) {
 971                         if (!ext2fs_bg_has_super(fs, i)) {
 972                                 group_blk += fs->super->s_blocks_per_group;
 973                                 continue;
 974                         }
 975                         for (blk = group_blk+1+new_blocks;
 976                              blk < group_blk+1+old_blocks; blk++) {
 977                                 ext2fs_block_alloc_stats2(fs, blk, -1);
 978                                 rfs->needed_blocks--;
 979                         }
 980                         group_blk += fs->super->s_blocks_per_group;
 981                 }
 982                 retval = 0;
 983                 goto errout;
 984         }
 985         /*
 986          * If we're increasing the number of descriptor blocks, life
 987          * gets interesting....
 988          */
 989         meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
 990         flex_bg = fs->super->s_feature_incompat &
 991                 EXT4_FEATURE_INCOMPAT_FLEX_BG;
 992         /* first reserve all of the existing fs meta blocks */
 993         for (i = 0; i < max_groups; i++) {
 994                 has_super = ext2fs_bg_has_super(fs, i);
 995                 if (has_super)
 996                         mark_fs_metablock(rfs, meta_bmap, i, group_blk);
 997
 998                 meta_bg = i / meta_bg_size;
 999                 if (!(fs->super->s_feature_incompat &
1000                       EXT2_FEATURE_INCOMPAT_META_BG) ||
1001                     (meta_bg < fs->super->s_first_meta_bg)) {
1002                         if (has_super) {
1003                                 for (blk = group_blk+1;
1004                                      blk < group_blk + 1 + new_blocks; blk++)
1005                                         mark_fs_metablock(rfs, meta_bmap,
1006                                                           i, blk);
1007                         }
1008                 } else {
1009                         if (has_super)
1010                                 has_super = 1;
1011                         if (((i % meta_bg_size) == 0) ||
1012                             ((i % meta_bg_size) == 1) ||
1013                             ((i % meta_bg_size) == (meta_bg_size-1)))
1014                                 mark_fs_metablock(rfs, meta_bmap, i,
1015                                                   group_blk + has_super);
1016                 }
1017
1018                 /*
1019                  * Reserve the existing meta blocks that we know
1020                  * aren't to be moved.
1021                  *
1022                  * For flex_bg file systems, in order to avoid
1023                  * overwriting fs metadata (especially inode table
1024                  * blocks) belonging to a different block group when
1025                  * we are relocating the inode tables, we need to
1026                  * reserve all existing fs metadata blocks.
1027                  */
1028                 if (ext2fs_block_bitmap_loc(fs, i))
1029                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
1030                                  ext2fs_block_bitmap_loc(fs, i));
1031                 else if (flex_bg && i < old_fs->group_desc_count)
1032                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
1033                                  ext2fs_block_bitmap_loc(old_fs, i));
1034
1035                 if (ext2fs_inode_bitmap_loc(fs, i))
1036                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
1037                                  ext2fs_inode_bitmap_loc(fs, i));
1038                 else if (flex_bg && i < old_fs->group_desc_count)
1039                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
1040                                  ext2fs_inode_bitmap_loc(old_fs, i));
1041
1042                 if (ext2fs_inode_table_loc(fs, i))
1043                         ext2fs_mark_block_bitmap_range2(rfs->reserve_blocks,
1044                                         ext2fs_inode_table_loc(fs, i),
1045                                         fs->inode_blocks_per_group);
1046                 else if (flex_bg && i < old_fs->group_desc_count)
1047                         ext2fs_mark_block_bitmap_range2(rfs->reserve_blocks,
1048                                         ext2fs_inode_table_loc(old_fs, i),
1049                                         old_fs->inode_blocks_per_group);
1050
1051                 group_blk += rfs->new_fs->super->s_blocks_per_group;
1052         }
1053
1054         /* Allocate the missing data structures */
1055         for (i = 0; i < max_groups; i++) {
1056                 if (ext2fs_inode_table_loc(fs, i) &&
1057                     ext2fs_inode_bitmap_loc(fs, i) &&
1058                     ext2fs_block_bitmap_loc(fs, i))
1059                         continue;
1060
1061                 retval = ext2fs_allocate_group_table(fs, i,
1062                                                      rfs->reserve_blocks);
1063                 if (retval)
1064                         goto errout;
1065
1066                 /*
1067                  * For those structures that have changed, we need to
1068                  * do bookkeepping.
1069                  */
1070                 if (ext2fs_block_bitmap_loc(old_fs, i) !=
1071                     (blk = ext2fs_block_bitmap_loc(fs, i))) {
1072                         ext2fs_block_alloc_stats2(fs, blk, +1);
1073                         if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
1074                             !ext2fs_test_block_bitmap2(meta_bmap, blk))
1075                                 ext2fs_mark_block_bitmap2(rfs->move_blocks,
1076                                                          blk);
1077                 }
1078                 if (ext2fs_inode_bitmap_loc(old_fs, i) !=
1079                     (blk = ext2fs_inode_bitmap_loc(fs, i))) {
1080                         ext2fs_block_alloc_stats2(fs, blk, +1);
1081                         if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
1082                             !ext2fs_test_block_bitmap2(meta_bmap, blk))
1083                                 ext2fs_mark_block_bitmap2(rfs->move_blocks,
1084                                                          blk);
1085                 }
1086
1087                 /*
1088                  * The inode table, if we need to relocate it, is
1089                  * handled specially.  We have to reserve the blocks
1090                  * for both the old and the new inode table, since we
1091                  * can't have the inode table be destroyed during the
1092                  * block relocation phase.
1093                  */
1094                 if (ext2fs_inode_table_loc(fs, i) == ext2fs_inode_table_loc(old_fs, i))
1095                         continue;       /* inode table not moved */
1096
1097                 rfs->needed_blocks += fs->inode_blocks_per_group;
1098
1099                 /*
1100                  * Mark the new inode table as in use in the new block
1101                  * allocation bitmap, and move any blocks that might
1102                  * be necessary.
1103                  */
1104                 for (blk = ext2fs_inode_table_loc(fs, i), j=0;
1105                      j < fs->inode_blocks_per_group ; j++, blk++) {
1106                         ext2fs_block_alloc_stats2(fs, blk, +1);
1107                         if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
1108                             !ext2fs_test_block_bitmap2(meta_bmap, blk))
1109                                 ext2fs_mark_block_bitmap2(rfs->move_blocks,
1110                                                          blk);
1111                 }
1112
1113                 /*
1114                  * Make sure the old inode table is reserved in the
1115                  * block reservation bitmap.
1116                  */
1117                 for (blk = ext2fs_inode_table_loc(rfs->old_fs, i), j=0;
1118                      j < fs->inode_blocks_per_group ; j++, blk++)
1119                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
1120         }
1121         retval = 0;
1122
1123 errout:
1124         if (meta_bmap)
1125                 ext2fs_free_block_bitmap(meta_bmap);
1126
1127         return retval;
1128 }
1129
1130 /*
1131  * This helper function tries to allocate a new block.  We try to
1132  * avoid hitting the original group descriptor blocks at least at
1133  * first, since we want to make it possible to recover from a badly
1134  * aborted resize operation as much as possible.
1135  *
1136  * In the future, I may further modify this routine to balance out
1137  * where we get the new blocks across the various block groups.
1138  * Ideally we would allocate blocks that corresponded with the block
1139  * group of the containing inode, and keep contiguous blocks
1140  * together.  However, this very difficult to do efficiently, since we
1141  * don't have the necessary information up front.
1142  */
1143
1144 #define AVOID_OLD       1
1145 #define DESPERATION     2
1146
1147 static void init_block_alloc(ext2_resize_t rfs)
1148 {
1149         rfs->alloc_state = AVOID_OLD;
1150         rfs->new_blk = rfs->new_fs->super->s_first_data_block;
1151 #if 0
1152         /* HACK for testing */
1153         if (ext2fs_blocks_count(rfs->new_fs->super) >
1154             ext2fs_blocks_count(rfs->old_fs->super))
1155                 rfs->new_blk = ext2fs_blocks_count(rfs->old_fs->super);
1156 #endif
1157 }
1158
1159 static blk64_t get_new_block(ext2_resize_t rfs)
1160 {
1161         ext2_filsys     fs = rfs->new_fs;
1162
1163         while (1) {
1164                 if (rfs->new_blk >= ext2fs_blocks_count(fs->super)) {
1165                         if (rfs->alloc_state == DESPERATION)
1166                                 return 0;
1167
1168 #ifdef RESIZE2FS_DEBUG
1169                         if (rfs->flags & RESIZE_DEBUG_BMOVE)
1170                                 printf("Going into desperation mode "
1171                                        "for block allocations\n");
1172 #endif
1173                         rfs->alloc_state = DESPERATION;
1174                         rfs->new_blk = fs->super->s_first_data_block;
1175                         continue;
1176                 }
1177                 if (ext2fs_test_block_bitmap2(fs->block_map, rfs->new_blk) ||
1178                     ext2fs_test_block_bitmap2(rfs->reserve_blocks,
1179                                              rfs->new_blk) ||
1180                     ((rfs->alloc_state == AVOID_OLD) &&
1181                      (rfs->new_blk < ext2fs_blocks_count(rfs->old_fs->super)) &&
1182                      ext2fs_test_block_bitmap2(rfs->old_fs->block_map,
1183                                               rfs->new_blk))) {
1184                         rfs->new_blk++;
1185                         continue;
1186                 }
1187                 return rfs->new_blk;
1188         }
1189 }
1190
1191 static errcode_t resize2fs_get_alloc_block(ext2_filsys fs, blk64_t goal,
1192                                            blk64_t *ret)
1193 {
1194         ext2_resize_t rfs = (ext2_resize_t) fs->priv_data;
1195         blk64_t blk;
1196
1197         blk = get_new_block(rfs);
1198         if (!blk)
1199                 return ENOSPC;
1200
1201 #ifdef RESIZE2FS_DEBUG
1202         if (rfs->flags & 0xF)
1203                 printf("get_alloc_block allocating %llu\n", blk);
1204 #endif
1205
1206         ext2fs_mark_block_bitmap2(rfs->old_fs->block_map, blk);
1207         ext2fs_mark_block_bitmap2(rfs->new_fs->block_map, blk);
1208         *ret = (blk64_t) blk;
1209         return 0;
1210 }
1211
1212 static errcode_t block_mover(ext2_resize_t rfs)
1213 {
1214         blk64_t                 blk, old_blk, new_blk;
1215         ext2_filsys             fs = rfs->new_fs;
1216         ext2_filsys             old_fs = rfs->old_fs;
1217         errcode_t               retval;
1218         __u64                   size;
1219         int                     c;
1220         int                     to_move, moved;
1221         ext2_badblocks_list     badblock_list = 0;
1222         int                     bb_modified = 0;
1223
1224         fs->get_alloc_block = resize2fs_get_alloc_block;
1225         old_fs->get_alloc_block = resize2fs_get_alloc_block;
1226
1227         retval = ext2fs_read_bb_inode(old_fs, &badblock_list);
1228         if (retval)
1229                 return retval;
1230
1231         new_blk = fs->super->s_first_data_block;
1232         if (!rfs->itable_buf) {
1233                 retval = ext2fs_get_array(fs->blocksize,
1234                                         fs->inode_blocks_per_group,
1235                                         &rfs->itable_buf);
1236                 if (retval)
1237                         return retval;
1238         }
1239         retval = ext2fs_create_extent_table(&rfs->bmap, 0);
1240         if (retval)
1241                 return retval;
1242
1243         /*
1244          * The first step is to figure out where all of the blocks
1245          * will go.
1246          */
1247         to_move = moved = 0;
1248         init_block_alloc(rfs);
1249         for (blk = B2C(old_fs->super->s_first_data_block);
1250              blk < ext2fs_blocks_count(old_fs->super);
1251              blk += EXT2FS_CLUSTER_RATIO(fs)) {
1252                 if (!ext2fs_test_block_bitmap2(old_fs->block_map, blk))
1253                         continue;
1254                 if (!ext2fs_test_block_bitmap2(rfs->move_blocks, blk))
1255                         continue;
1256                 if (ext2fs_badblocks_list_test(badblock_list, blk)) {
1257                         ext2fs_badblocks_list_del(badblock_list, blk);
1258                         bb_modified++;
1259                         continue;
1260                 }
1261
1262                 new_blk = get_new_block(rfs);
1263                 if (!new_blk) {
1264                         retval = ENOSPC;
1265                         goto errout;
1266                 }
1267                 ext2fs_block_alloc_stats2(fs, new_blk, +1);
1268                 ext2fs_add_extent_entry(rfs->bmap, B2C(blk), B2C(new_blk));
1269                 to_move++;
1270         }
1271
1272         if (to_move == 0) {
1273                 if (rfs->bmap) {
1274                         ext2fs_free_extent_table(rfs->bmap);
1275                         rfs->bmap = 0;
1276                 }
1277                 retval = 0;
1278                 goto errout;
1279         }
1280
1281         /*
1282          * Step two is to actually move the blocks
1283          */
1284         retval =  ext2fs_iterate_extent(rfs->bmap, 0, 0, 0);
1285         if (retval) goto errout;
1286
1287         if (rfs->progress) {
1288                 retval = (rfs->progress)(rfs, E2_RSZ_BLOCK_RELOC_PASS,
1289                                          0, to_move);
1290                 if (retval)
1291                         goto errout;
1292         }
1293         while (1) {
1294                 retval = ext2fs_iterate_extent(rfs->bmap, &old_blk, &new_blk, &size);
1295                 if (retval) goto errout;
1296                 if (!size)
1297                         break;
1298                 old_blk = C2B(old_blk);
1299                 new_blk = C2B(new_blk);
1300                 size = C2B(size);
1301 #ifdef RESIZE2FS_DEBUG
1302                 if (rfs->flags & RESIZE_DEBUG_BMOVE)
1303                         printf("Moving %llu blocks %llu->%llu\n",
1304                                size, old_blk, new_blk);
1305 #endif
1306                 do {
1307                         c = size;
1308                         if (c > fs->inode_blocks_per_group)
1309                                 c = fs->inode_blocks_per_group;
1310                         retval = io_channel_read_blk64(fs->io, old_blk, c,
1311                                                        rfs->itable_buf);
1312                         if (retval) goto errout;
1313                         retval = io_channel_write_blk64(fs->io, new_blk, c,
1314                                                         rfs->itable_buf);
1315                         if (retval) goto errout;
1316                         size -= c;
1317                         new_blk += c;
1318                         old_blk += c;
1319                         moved += c;
1320                         if (rfs->progress) {
1321                                 io_channel_flush(fs->io);
1322                                 retval = (rfs->progress)(rfs,
1323                                                 E2_RSZ_BLOCK_RELOC_PASS,
1324                                                 moved, to_move);
1325                                 if (retval)
1326                                         goto errout;
1327                         }
1328                 } while (size > 0);
1329                 io_channel_flush(fs->io);
1330         }
1331
1332 errout:
1333         if (badblock_list) {
1334                 if (!retval && bb_modified)
1335                         retval = ext2fs_update_bb_inode(old_fs,
1336                                                         badblock_list);
1337                 ext2fs_badblocks_list_free(badblock_list);
1338         }
1339         return retval;
1340 }
1341
1342
1343 /* --------------------------------------------------------------------
1344  *
1345  * Resize processing, phase 3
1346  *
1347  * --------------------------------------------------------------------
1348  */
1349
1350
1351 /*
1352  * The extent translation table is stored in clusters so we need to
1353  * take special care when mapping a source block number to its
1354  * destination block number.
1355  */
1356 __u64 extent_translate(ext2_filsys fs, ext2_extent extent, __u64 old_loc)
1357 {
1358         __u64 new_block = C2B(ext2fs_extent_translate(extent, B2C(old_loc)));
1359
1360         if (new_block != 0)
1361                 new_block += old_loc & (EXT2FS_CLUSTER_RATIO(fs) - 1);
1362         return new_block;
1363 }
1364
1365 struct process_block_struct {
1366         ext2_resize_t           rfs;
1367         ext2_ino_t              ino;
1368         struct ext2_inode *     inode;
1369         errcode_t               error;
1370         int                     is_dir;
1371         int                     changed;
1372 };
1373
1374 static int process_block(ext2_filsys fs, blk64_t        *block_nr,
1375                          e2_blkcnt_t blockcnt,
1376                          blk64_t ref_block EXT2FS_ATTR((unused)),
1377                          int ref_offset EXT2FS_ATTR((unused)), void *priv_data)
1378 {
1379         struct process_block_struct *pb;
1380         errcode_t       retval;
1381         blk64_t         block, new_block;
1382         int             ret = 0;
1383
1384         pb = (struct process_block_struct *) priv_data;
1385         block = *block_nr;
1386         if (pb->rfs->bmap) {
1387                 new_block = extent_translate(fs, pb->rfs->bmap, block);
1388                 if (new_block) {
1389                         *block_nr = new_block;
1390                         ret |= BLOCK_CHANGED;
1391                         pb->changed = 1;
1392 #ifdef RESIZE2FS_DEBUG
1393                         if (pb->rfs->flags & RESIZE_DEBUG_BMOVE)
1394                                 printf("ino=%u, blockcnt=%lld, %llu->%llu\n",
1395                                        pb->ino, blockcnt, block, new_block);
1396 #endif
1397                         block = new_block;
1398                 }
1399         }
1400         if (pb->is_dir) {
1401                 retval = ext2fs_add_dir_block2(fs->dblist, pb->ino,
1402                                                block, (int) blockcnt);
1403                 if (retval) {
1404                         pb->error = retval;
1405                         ret |= BLOCK_ABORT;
1406                 }
1407         }
1408         return ret;
1409 }
1410
1411 /*
1412  * Progress callback
1413  */
1414 static errcode_t progress_callback(ext2_filsys fs,
1415                                    ext2_inode_scan scan EXT2FS_ATTR((unused)),
1416                                    dgrp_t group, void * priv_data)
1417 {
1418         ext2_resize_t rfs = (ext2_resize_t) priv_data;
1419         errcode_t               retval;
1420
1421         /*
1422          * This check is to protect against old ext2 libraries.  It
1423          * shouldn't be needed against new libraries.
1424          */
1425         if ((group+1) == 0)
1426                 return 0;
1427
1428         if (rfs->progress) {
1429                 io_channel_flush(fs->io);
1430                 retval = (rfs->progress)(rfs, E2_RSZ_INODE_SCAN_PASS,
1431                                          group+1, fs->group_desc_count);
1432                 if (retval)
1433                         return retval;
1434         }
1435
1436         return 0;
1437 }
1438
1439 static errcode_t inode_scan_and_fix(ext2_resize_t rfs)
1440 {
1441         struct process_block_struct     pb;
1442         ext2_ino_t              ino, new_inode;
1443         struct ext2_inode       *inode = NULL;
1444         ext2_inode_scan         scan = NULL;
1445         errcode_t               retval;
1446         char                    *block_buf = 0;
1447         ext2_ino_t              start_to_move;
1448         blk64_t                 orig_size;
1449         blk64_t                 new_block;
1450         int                     inode_size;
1451
1452         if ((rfs->old_fs->group_desc_count <=
1453              rfs->new_fs->group_desc_count) &&
1454             !rfs->bmap)
1455                 return 0;
1456
1457         /*
1458          * Save the original size of the old filesystem, and
1459          * temporarily set the size to be the new size if the new size
1460          * is larger.  We need to do this to avoid catching an error
1461          * by the block iterator routines
1462          */
1463         orig_size = ext2fs_blocks_count(rfs->old_fs->super);
1464         if (orig_size < ext2fs_blocks_count(rfs->new_fs->super))
1465                 ext2fs_blocks_count_set(rfs->old_fs->super,
1466                                 ext2fs_blocks_count(rfs->new_fs->super));
1467
1468         retval = ext2fs_open_inode_scan(rfs->old_fs, 0, &scan);
1469         if (retval) goto errout;
1470
1471         retval = ext2fs_init_dblist(rfs->old_fs, 0);
1472         if (retval) goto errout;
1473         retval = ext2fs_get_array(rfs->old_fs->blocksize, 3, &block_buf);
1474         if (retval) goto errout;
1475
1476         start_to_move = (rfs->new_fs->group_desc_count *
1477                          rfs->new_fs->super->s_inodes_per_group);
1478
1479         if (rfs->progress) {
1480                 retval = (rfs->progress)(rfs, E2_RSZ_INODE_SCAN_PASS,
1481                                          0, rfs->old_fs->group_desc_count);
1482                 if (retval)
1483                         goto errout;
1484         }
1485         ext2fs_set_inode_callback(scan, progress_callback, (void *) rfs);
1486         pb.rfs = rfs;
1487         pb.inode = inode;
1488         pb.error = 0;
1489         new_inode = EXT2_FIRST_INODE(rfs->new_fs->super);
1490         inode_size = EXT2_INODE_SIZE(rfs->new_fs->super);
1491         inode = malloc(inode_size);
1492         if (!inode) {
1493                 retval = ENOMEM;
1494                 goto errout;
1495         }
1496         /*
1497          * First, copy all of the inodes that need to be moved
1498          * elsewhere in the inode table
1499          */
1500         while (1) {
1501                 retval = ext2fs_get_next_inode_full(scan, &ino, inode, inode_size);
1502                 if (retval) goto errout;
1503                 if (!ino)
1504                         break;
1505
1506                 if (inode->i_links_count == 0 && ino != EXT2_RESIZE_INO)
1507                         continue; /* inode not in use */
1508
1509                 pb.is_dir = LINUX_S_ISDIR(inode->i_mode);
1510                 pb.changed = 0;
1511
1512                 if (ext2fs_file_acl_block(rfs->old_fs, inode) && rfs->bmap) {
1513                         new_block = extent_translate(rfs->old_fs, rfs->bmap,
1514                                 ext2fs_file_acl_block(rfs->old_fs, inode));
1515                         if (new_block) {
1516                                 ext2fs_file_acl_block_set(rfs->old_fs, inode,
1517                                                           new_block);
1518                                 retval = ext2fs_write_inode_full(rfs->old_fs,
1519                                                             ino, inode, inode_size);
1520                                 if (retval) goto errout;
1521                         }
1522                 }
1523
1524                 if (ext2fs_inode_has_valid_blocks2(rfs->old_fs, inode) &&
1525                     (rfs->bmap || pb.is_dir)) {
1526                         pb.ino = ino;
1527                         retval = ext2fs_block_iterate3(rfs->old_fs,
1528                                                        ino, 0, block_buf,
1529                                                        process_block, &pb);
1530                         if (retval)
1531                                 goto errout;
1532                         if (pb.error) {
1533                                 retval = pb.error;
1534                                 goto errout;
1535                         }
1536                 }
1537
1538                 if (ino <= start_to_move)
1539                         continue; /* Don't need to move it. */
1540
1541                 /*
1542                  * Find a new inode
1543                  */
1544                 retval = ext2fs_new_inode(rfs->new_fs, 0, 0, 0, &new_inode);
1545                 if (retval)
1546                         goto errout;
1547
1548                 ext2fs_inode_alloc_stats2(rfs->new_fs, new_inode, +1,
1549                                           pb.is_dir);
1550                 if (pb.changed) {
1551                         /* Get the new version of the inode */
1552                         retval = ext2fs_read_inode_full(rfs->old_fs, ino,
1553                                                 inode, inode_size);
1554                         if (retval) goto errout;
1555                 }
1556                 inode->i_ctime = time(0);
1557                 retval = ext2fs_write_inode_full(rfs->old_fs, new_inode,
1558                                                 inode, inode_size);
1559                 if (retval) goto errout;
1560
1561 #ifdef RESIZE2FS_DEBUG
1562                 if (rfs->flags & RESIZE_DEBUG_INODEMAP)
1563                         printf("Inode moved %u->%u\n", ino, new_inode);
1564 #endif
1565                 if (!rfs->imap) {
1566                         retval = ext2fs_create_extent_table(&rfs->imap, 0);
1567                         if (retval)
1568                                 goto errout;
1569                 }
1570                 ext2fs_add_extent_entry(rfs->imap, ino, new_inode);
1571         }
1572         io_channel_flush(rfs->old_fs->io);
1573
1574 errout:
1575         ext2fs_blocks_count_set(rfs->old_fs->super, orig_size);
1576         if (rfs->bmap) {
1577                 ext2fs_free_extent_table(rfs->bmap);
1578                 rfs->bmap = 0;
1579         }
1580         if (scan)
1581                 ext2fs_close_inode_scan(scan);
1582         if (block_buf)
1583                 ext2fs_free_mem(&block_buf);
1584         free(inode);
1585         return retval;
1586 }
1587
1588 /* --------------------------------------------------------------------
1589  *
1590  * Resize processing, phase 4.
1591  *
1592  * --------------------------------------------------------------------
1593  */
1594
1595 struct istruct {
1596         ext2_resize_t rfs;
1597         errcode_t       err;
1598         unsigned int    max_dirs;
1599         unsigned int    num;
1600 };
1601
1602 static int check_and_change_inodes(ext2_ino_t dir,
1603                                    int entry EXT2FS_ATTR((unused)),
1604                                    struct ext2_dir_entry *dirent, int offset,
1605                                    int  blocksize EXT2FS_ATTR((unused)),
1606                                    char *buf EXT2FS_ATTR((unused)),
1607                                    void *priv_data)
1608 {
1609         struct istruct *is = (struct istruct *) priv_data;
1610         struct ext2_inode       inode;
1611         ext2_ino_t              new_inode;
1612         errcode_t               retval;
1613
1614         if (is->rfs->progress && offset == 0) {
1615                 io_channel_flush(is->rfs->old_fs->io);
1616                 is->err = (is->rfs->progress)(is->rfs,
1617                                               E2_RSZ_INODE_REF_UPD_PASS,
1618                                               ++is->num, is->max_dirs);
1619                 if (is->err)
1620                         return DIRENT_ABORT;
1621         }
1622
1623         if (!dirent->inode)
1624                 return 0;
1625
1626         new_inode = ext2fs_extent_translate(is->rfs->imap, dirent->inode);
1627
1628         if (!new_inode)
1629                 return 0;
1630 #ifdef RESIZE2FS_DEBUG
1631         if (is->rfs->flags & RESIZE_DEBUG_INODEMAP)
1632                 printf("Inode translate (dir=%u, name=%.*s, %u->%u)\n",
1633                        dir, dirent->name_len&0xFF, dirent->name,
1634                        dirent->inode, new_inode);
1635 #endif
1636
1637         dirent->inode = new_inode;
1638
1639         /* Update the directory mtime and ctime */
1640         retval = ext2fs_read_inode(is->rfs->old_fs, dir, &inode);
1641         if (retval == 0) {
1642                 inode.i_mtime = inode.i_ctime = time(0);
1643                 is->err = ext2fs_write_inode(is->rfs->old_fs, dir, &inode);
1644                 if (is->err)
1645                         return DIRENT_ABORT;
1646         }
1647
1648         return DIRENT_CHANGED;
1649 }
1650
1651 static errcode_t inode_ref_fix(ext2_resize_t rfs)
1652 {
1653         errcode_t               retval;
1654         struct istruct          is;
1655
1656         if (!rfs->imap)
1657                 return 0;
1658
1659         /*
1660          * Now, we iterate over all of the directories to update the
1661          * inode references
1662          */
1663         is.num = 0;
1664         is.max_dirs = ext2fs_dblist_count2(rfs->old_fs->dblist);
1665         is.rfs = rfs;
1666         is.err = 0;
1667
1668         if (rfs->progress) {
1669                 retval = (rfs->progress)(rfs, E2_RSZ_INODE_REF_UPD_PASS,
1670                                          0, is.max_dirs);
1671                 if (retval)
1672                         goto errout;
1673         }
1674
1675         retval = ext2fs_dblist_dir_iterate(rfs->old_fs->dblist,
1676                                            DIRENT_FLAG_INCLUDE_EMPTY, 0,
1677                                            check_and_change_inodes, &is);
1678         if (retval)
1679                 goto errout;
1680         if (is.err) {
1681                 retval = is.err;
1682                 goto errout;
1683         }
1684
1685         if (rfs->progress && (is.num < is.max_dirs))
1686                 (rfs->progress)(rfs, E2_RSZ_INODE_REF_UPD_PASS,
1687                                 is.max_dirs, is.max_dirs);
1688
1689 errout:
1690         ext2fs_free_extent_table(rfs->imap);
1691         rfs->imap = 0;
1692         return retval;
1693 }
1694
1695
1696 /* --------------------------------------------------------------------
1697  *
1698  * Resize processing, phase 5.
1699  *
1700  * In this phase we actually move the inode table around, and then
1701  * update the summary statistics.  This is scary, since aborting here
1702  * will potentially scramble the filesystem.  (We are moving the
1703  * inode tables around in place, and so the potential for lost data,
1704  * or at the very least scrambling the mapping between filenames and
1705  * inode numbers is very high in case of a power failure here.)
1706  * --------------------------------------------------------------------
1707  */
1708
1709
1710 /*
1711  * A very scary routine --- this one moves the inode table around!!!
1712  *
1713  * After this you have to use the rfs->new_fs file handle to read and
1714  * write inodes.
1715  */
1716 static errcode_t move_itables(ext2_resize_t rfs)
1717 {
1718         int             n, num, size;
1719         long long       diff;
1720         dgrp_t          i, max_groups;
1721         ext2_filsys     fs = rfs->new_fs;
1722         char            *cp;
1723         blk64_t         old_blk, new_blk, blk;
1724         errcode_t       retval;
1725         int             j, to_move, moved;
1726
1727         max_groups = fs->group_desc_count;
1728         if (max_groups > rfs->old_fs->group_desc_count)
1729                 max_groups = rfs->old_fs->group_desc_count;
1730
1731         size = fs->blocksize * fs->inode_blocks_per_group;
1732         if (!rfs->itable_buf) {
1733                 retval = ext2fs_get_mem(size, &rfs->itable_buf);
1734                 if (retval)
1735                         return retval;
1736         }
1737
1738         /*
1739          * Figure out how many inode tables we need to move
1740          */
1741         to_move = moved = 0;
1742         for (i=0; i < max_groups; i++)
1743                 if (ext2fs_inode_table_loc(rfs->old_fs, i) !=
1744                     ext2fs_inode_table_loc(fs, i))
1745                         to_move++;
1746
1747         if (to_move == 0)
1748                 return 0;
1749
1750         if (rfs->progress) {
1751                 retval = rfs->progress(rfs, E2_RSZ_MOVE_ITABLE_PASS,
1752                                        0, to_move);
1753                 if (retval)
1754                         goto errout;
1755         }
1756
1757         rfs->old_fs->flags |= EXT2_FLAG_MASTER_SB_ONLY;
1758
1759         for (i=0; i < max_groups; i++) {
1760                 old_blk = ext2fs_inode_table_loc(rfs->old_fs, i);
1761                 new_blk = ext2fs_inode_table_loc(fs, i);
1762                 diff = new_blk - old_blk;
1763
1764 #ifdef RESIZE2FS_DEBUG
1765                 if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
1766                         printf("Itable move group %d block %llu->%llu (diff %lld)\n",
1767                                i, old_blk, new_blk, diff);
1768 #endif
1769
1770                 if (!diff)
1771                         continue;
1772
1773                 retval = io_channel_read_blk64(fs->io, old_blk,
1774                                                fs->inode_blocks_per_group,
1775                                                rfs->itable_buf);
1776                 if (retval)
1777                         goto errout;
1778                 /*
1779                  * The end of the inode table segment often contains
1780                  * all zeros, and we're often only moving the inode
1781                  * table down a block or two.  If so, we can optimize
1782                  * things by not rewriting blocks that we know to be zero
1783                  * already.
1784                  */
1785                 for (cp = rfs->itable_buf+size-1, n=0; n < size; n++, cp--)
1786                         if (*cp)
1787                                 break;
1788                 n = n >> EXT2_BLOCK_SIZE_BITS(fs->super);
1789 #ifdef RESIZE2FS_DEBUG
1790                 if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
1791                         printf("%d blocks of zeros...\n", n);
1792 #endif
1793                 num = fs->inode_blocks_per_group;
1794                 if (n > diff)
1795                         num -= n;
1796
1797                 retval = io_channel_write_blk64(fs->io, new_blk,
1798                                                 num, rfs->itable_buf);
1799                 if (retval) {
1800                         io_channel_write_blk64(fs->io, old_blk,
1801                                                num, rfs->itable_buf);
1802                         goto errout;
1803                 }
1804                 if (n > diff) {
1805                         retval = io_channel_write_blk64(fs->io,
1806                               old_blk + fs->inode_blocks_per_group,
1807                               diff, (rfs->itable_buf +
1808                                      (fs->inode_blocks_per_group - diff) *
1809                                      fs->blocksize));
1810                         if (retval)
1811                                 goto errout;
1812                 }
1813
1814                 for (blk = ext2fs_inode_table_loc(rfs->old_fs, i), j=0;
1815                      j < fs->inode_blocks_per_group ; j++, blk++)
1816                         ext2fs_block_alloc_stats2(fs, blk, -1);
1817
1818                 ext2fs_inode_table_loc_set(rfs->old_fs, i, new_blk);
1819                 ext2fs_group_desc_csum_set(rfs->old_fs, i);
1820                 ext2fs_mark_super_dirty(rfs->old_fs);
1821                 ext2fs_flush(rfs->old_fs);
1822
1823                 if (rfs->progress) {
1824                         retval = rfs->progress(rfs, E2_RSZ_MOVE_ITABLE_PASS,
1825                                                ++moved, to_move);
1826                         if (retval)
1827                                 goto errout;
1828                 }
1829         }
1830         mark_table_blocks(fs, fs->block_map);
1831         ext2fs_flush(fs);
1832 #ifdef RESIZE2FS_DEBUG
1833         if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
1834                 printf("Inode table move finished.\n");
1835 #endif
1836         return 0;
1837
1838 errout:
1839         return retval;
1840 }
1841
1842 /*
1843  * Fix the resize inode
1844  */
1845 static errcode_t fix_resize_inode(ext2_filsys fs)
1846 {
1847         struct ext2_inode       inode;
1848         errcode_t               retval;
1849         char                    *block_buf = NULL;
1850
1851         if (!(fs->super->s_feature_compat &
1852               EXT2_FEATURE_COMPAT_RESIZE_INODE))
1853                 return 0;
1854
1855         retval = ext2fs_get_mem(fs->blocksize, &block_buf);
1856         if (retval) goto errout;
1857
1858         retval = ext2fs_read_inode(fs, EXT2_RESIZE_INO, &inode);
1859         if (retval) goto errout;
1860
1861         ext2fs_iblk_set(fs, &inode, 1);
1862
1863         retval = ext2fs_write_inode(fs, EXT2_RESIZE_INO, &inode);
1864         if (retval) goto errout;
1865
1866         if (!inode.i_block[EXT2_DIND_BLOCK]) {
1867                 /*
1868                  * Avoid zeroing out block #0; that's rude.  This
1869                  * should never happen anyway since the filesystem
1870                  * should be fsck'ed and we assume it is consistent.
1871                  */
1872                 fprintf(stderr,
1873                         _("Should never happen: resize inode corrupt!\n"));
1874                 exit(1);
1875         }
1876
1877         memset(block_buf, 0, fs->blocksize);
1878
1879         retval = io_channel_write_blk64(fs->io, inode.i_block[EXT2_DIND_BLOCK],
1880                                         1, block_buf);
1881         if (retval) goto errout;
1882
1883         retval = ext2fs_create_resize_inode(fs);
1884         if (retval)
1885                 goto errout;
1886
1887 errout:
1888         if (block_buf)
1889                 ext2fs_free_mem(&block_buf);
1890         return retval;
1891 }
1892
1893 /*
1894  * Finally, recalculate the summary information
1895  */
1896 static errcode_t ext2fs_calculate_summary_stats(ext2_filsys fs)
1897 {
1898         blk64_t         blk;
1899         ext2_ino_t      ino;
1900         unsigned int    group = 0;
1901         unsigned int    count = 0;
1902         blk64_t         total_blocks_free = 0;
1903         int             total_inodes_free = 0;
1904         int             group_free = 0;
1905         int             uninit = 0;
1906         blk64_t         super_blk, old_desc_blk, new_desc_blk;
1907         int             old_desc_blocks;
1908
1909         /*
1910          * First calculate the block statistics
1911          */
1912         uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_BLOCK_UNINIT);
1913         ext2fs_super_and_bgd_loc2(fs, group, &super_blk, &old_desc_blk,
1914                                   &new_desc_blk, 0);
1915         if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
1916                 old_desc_blocks = fs->super->s_first_meta_bg;
1917         else
1918                 old_desc_blocks = fs->desc_blocks +
1919                         fs->super->s_reserved_gdt_blocks;
1920         for (blk = B2C(fs->super->s_first_data_block);
1921              blk < ext2fs_blocks_count(fs->super);
1922              blk += EXT2FS_CLUSTER_RATIO(fs)) {
1923                 if ((uninit &&
1924                      !(EQ_CLSTR(blk, super_blk) ||
1925                        ((old_desc_blk && old_desc_blocks &&
1926                          GE_CLSTR(blk, old_desc_blk) &&
1927                          LT_CLSTR(blk, old_desc_blk + old_desc_blocks))) ||
1928                        ((new_desc_blk && EQ_CLSTR(blk, new_desc_blk))) ||
1929                        EQ_CLSTR(blk, ext2fs_block_bitmap_loc(fs, group)) ||
1930                        EQ_CLSTR(blk, ext2fs_inode_bitmap_loc(fs, group)) ||
1931                        ((GE_CLSTR(blk, ext2fs_inode_table_loc(fs, group)) &&
1932                          LT_CLSTR(blk, ext2fs_inode_table_loc(fs, group)
1933                                   + fs->inode_blocks_per_group))))) ||
1934                     (!ext2fs_fast_test_block_bitmap2(fs->block_map, blk))) {
1935                         group_free++;
1936                         total_blocks_free++;
1937                 }
1938                 count++;
1939                 if ((count == fs->super->s_clusters_per_group) ||
1940                     EQ_CLSTR(blk, ext2fs_blocks_count(fs->super)-1)) {
1941                         ext2fs_bg_free_blocks_count_set(fs, group, group_free);
1942                         ext2fs_group_desc_csum_set(fs, group);
1943                         group++;
1944                         if (group >= fs->group_desc_count)
1945                                 break;
1946                         count = 0;
1947                         group_free = 0;
1948                         uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_BLOCK_UNINIT);
1949                         ext2fs_super_and_bgd_loc2(fs, group, &super_blk,
1950                                                   &old_desc_blk,
1951                                                   &new_desc_blk, 0);
1952                         if (fs->super->s_feature_incompat &
1953                             EXT2_FEATURE_INCOMPAT_META_BG)
1954                                 old_desc_blocks = fs->super->s_first_meta_bg;
1955                         else
1956                                 old_desc_blocks = fs->desc_blocks +
1957                                         fs->super->s_reserved_gdt_blocks;
1958                 }
1959         }
1960         total_blocks_free = C2B(total_blocks_free);
1961         ext2fs_free_blocks_count_set(fs->super, total_blocks_free);
1962
1963         /*
1964          * Next, calculate the inode statistics
1965          */
1966         group_free = 0;
1967         count = 0;
1968         group = 0;
1969
1970         /* Protect loop from wrap-around if s_inodes_count maxed */
1971         uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_INODE_UNINIT);
1972         for (ino = 1; ino <= fs->super->s_inodes_count && ino > 0; ino++) {
1973                 if (uninit ||
1974                     !ext2fs_fast_test_inode_bitmap2(fs->inode_map, ino)) {
1975                         group_free++;
1976                         total_inodes_free++;
1977                 }
1978                 count++;
1979                 if ((count == fs->super->s_inodes_per_group) ||
1980                     (ino == fs->super->s_inodes_count)) {
1981                         ext2fs_bg_free_inodes_count_set(fs, group, group_free);
1982                         ext2fs_group_desc_csum_set(fs, group);
1983                         group++;
1984                         if (group >= fs->group_desc_count)
1985                                 break;
1986                         count = 0;
1987                         group_free = 0;
1988                         uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_INODE_UNINIT);
1989                 }
1990         }
1991         fs->super->s_free_inodes_count = total_inodes_free;
1992         ext2fs_mark_super_dirty(fs);
1993         return 0;
1994 }
1995
1996 /*
1997  *  Journal may have been relocated; update the backup journal blocks
1998  *  in the superblock.
1999  */
2000 static errcode_t fix_sb_journal_backup(ext2_filsys fs)
2001 {
2002         errcode_t         retval;
2003         struct ext2_inode inode;
2004
2005         if (!(fs->super->s_feature_compat & EXT3_FEATURE_COMPAT_HAS_JOURNAL))
2006                 return 0;
2007
2008         /* External journal? Nothing to do. */
2009         if (fs->super->s_journal_dev && !fs->super->s_journal_inum)
2010                 return 0;
2011
2012         retval = ext2fs_read_inode(fs, fs->super->s_journal_inum, &inode);
2013         if (retval)
2014                 return retval;
2015         memcpy(fs->super->s_jnl_blocks, inode.i_block, EXT2_N_BLOCKS*4);
2016         fs->super->s_jnl_blocks[15] = inode.i_size_high;
2017         fs->super->s_jnl_blocks[16] = inode.i_size;
2018         fs->super->s_jnl_backup_type = EXT3_JNL_BACKUP_BLOCKS;
2019         ext2fs_mark_super_dirty(fs);
2020         return 0;
2021 }
2022
2023 static int calc_group_overhead(ext2_filsys fs, blk64_t grp,
2024                                int old_desc_blocks)
2025 {
2026         blk64_t super_blk, old_desc_blk, new_desc_blk;
2027         int overhead;
2028
2029         /* inode table blocks plus allocation bitmaps */
2030         overhead = fs->inode_blocks_per_group + 2;
2031
2032         ext2fs_super_and_bgd_loc2(fs, grp, &super_blk,
2033                                   &old_desc_blk, &new_desc_blk, 0);
2034         if ((grp == 0) || super_blk)
2035                 overhead++;
2036         if (old_desc_blk)
2037                 overhead += old_desc_blocks;
2038         else if (new_desc_blk)
2039                 overhead++;
2040         return overhead;
2041 }
2042
2043
2044 /*
2045  * calcluate the minimum number of blocks the given fs can be resized to
2046  */
2047 blk64_t calculate_minimum_resize_size(ext2_filsys fs, int flags)
2048 {
2049         ext2_ino_t inode_count;
2050         dgrp_t groups;
2051         blk64_t blks_needed, data_blocks;
2052         blk64_t grp, data_needed, last_start;
2053         blk64_t overhead = 0;
2054         int old_desc_blocks;
2055         int extra_groups = 0;
2056         int flexbg_size = 1 << fs->super->s_log_groups_per_flex;
2057
2058         /*
2059          * first figure out how many group descriptors we need to
2060          * handle the number of inodes we have
2061          */
2062         inode_count = fs->super->s_inodes_count -
2063                 fs->super->s_free_inodes_count;
2064         blks_needed = ext2fs_div_ceil(inode_count,
2065                                       fs->super->s_inodes_per_group) *
2066                 EXT2_BLOCKS_PER_GROUP(fs->super);
2067         groups = ext2fs_div64_ceil(blks_needed,
2068                                    EXT2_BLOCKS_PER_GROUP(fs->super));
2069 #ifdef RESIZE2FS_DEBUG
2070         if (flags & RESIZE_DEBUG_MIN_CALC)
2071                 printf("fs has %d inodes, %d groups required.\n",
2072                        inode_count, groups);
2073 #endif
2074
2075         /*
2076          * number of old-style block group descriptor blocks
2077          */
2078         if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
2079                 old_desc_blocks = fs->super->s_first_meta_bg;
2080         else
2081                 old_desc_blocks = fs->desc_blocks +
2082                         fs->super->s_reserved_gdt_blocks;
2083
2084         /* calculate how many blocks are needed for data */
2085         data_needed = ext2fs_blocks_count(fs->super) -
2086                 ext2fs_free_blocks_count(fs->super);
2087
2088         for (grp = 0; grp < fs->group_desc_count; grp++)
2089                 data_needed -= calc_group_overhead(fs, grp, old_desc_blocks);
2090 #ifdef RESIZE2FS_DEBUG
2091         if (flags & RESIZE_DEBUG_MIN_CALC)
2092                 printf("fs requires %llu data blocks.\n", data_needed);
2093 #endif
2094
2095         /*
2096          * For ext4 we need to allow for up to a flex_bg worth of
2097          * inode tables of slack space so the resize operation can be
2098          * guaranteed to finish.
2099          */
2100         if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_FLEX_BG) {
2101                 extra_groups = flexbg_size - (groups & (flexbg_size - 1));
2102                 data_needed += fs->inode_blocks_per_group * extra_groups;
2103                 extra_groups = groups % flexbg_size;
2104         }
2105
2106         /*
2107          * figure out how many data blocks we have given the number of groups
2108          * we need for our inodes
2109          */
2110         data_blocks = groups * EXT2_BLOCKS_PER_GROUP(fs->super);
2111         last_start = 0;
2112         for (grp = 0; grp < groups; grp++) {
2113                 overhead = calc_group_overhead(fs, grp, old_desc_blocks);
2114
2115                 /*
2116                  * we want to keep track of how much data we can store in
2117                  * the groups leading up to the last group so we can determine
2118                  * how big the last group needs to be
2119                  */
2120                 if (grp != (groups - 1))
2121                         last_start += EXT2_BLOCKS_PER_GROUP(fs->super) -
2122                                 overhead;
2123
2124                 data_blocks -= overhead;
2125         }
2126 #ifdef RESIZE2FS_DEBUG
2127         if (flags & RESIZE_DEBUG_MIN_CALC)
2128                 printf("With %d group(s), we have %llu blocks available.\n",
2129                        groups, data_blocks);
2130 #endif
2131
2132         /*
2133          * if we need more group descriptors in order to accomodate our data
2134          * then we need to add them here
2135          */
2136         while (data_needed > data_blocks) {
2137                 blk64_t remainder = data_needed - data_blocks;
2138                 dgrp_t extra_grps;
2139
2140                 /* figure out how many more groups we need for the data */
2141                 extra_grps = ext2fs_div64_ceil(remainder,
2142                                                EXT2_BLOCKS_PER_GROUP(fs->super));
2143
2144                 data_blocks += extra_grps * EXT2_BLOCKS_PER_GROUP(fs->super);
2145
2146                 /* ok we have to account for the last group */
2147                 overhead = calc_group_overhead(fs, groups-1, old_desc_blocks);
2148                 last_start += EXT2_BLOCKS_PER_GROUP(fs->super) - overhead;
2149
2150                 for (grp = groups; grp < groups+extra_grps; grp++) {
2151                         overhead = calc_group_overhead(fs, grp,
2152                                                        old_desc_blocks);
2153
2154                         /*
2155                          * again, we need to see how much data we cram into
2156                          * all of the groups leading up to the last group
2157                          */
2158                         if (grp != (groups + extra_grps - 1))
2159                                 last_start += EXT2_BLOCKS_PER_GROUP(fs->super)
2160                                         - overhead;
2161
2162                         data_blocks -= overhead;
2163                 }
2164
2165                 groups += extra_grps;
2166                 extra_groups += extra_grps;
2167                 if (fs->super->s_feature_incompat
2168                         & EXT4_FEATURE_INCOMPAT_FLEX_BG
2169                     && extra_groups > flexbg_size) {
2170                         /*
2171                          * For ext4 we need to allow for up to a flex_bg worth
2172                          * of inode tables of slack space so the resize
2173                          * operation can be guaranteed to finish.
2174                          */
2175                         extra_groups = flexbg_size -
2176                                                 (groups & (flexbg_size - 1));
2177                         data_needed += (fs->inode_blocks_per_group *
2178                                         extra_groups);
2179                         extra_groups = groups % flexbg_size;
2180                 }
2181 #ifdef RESIZE2FS_DEBUG
2182                 if (flags & RESIZE_DEBUG_MIN_CALC)
2183                         printf("Added %d extra group(s), "
2184                                "data_needed %llu, data_blocks %llu, "
2185                                "last_start %llu\n",
2186                                extra_grps, data_needed, data_blocks,
2187                                last_start);
2188 #endif
2189         }
2190
2191         /* now for the fun voodoo */
2192         overhead = calc_group_overhead(fs, groups-1, old_desc_blocks);
2193 #ifdef RESIZE2FS_DEBUG
2194         if (flags & RESIZE_DEBUG_MIN_CALC)
2195                 printf("Last group's overhead is %llu\n", overhead);
2196 #endif
2197
2198         /*
2199          * if this is the case then the last group is going to have data in it
2200          * so we need to adjust the size of the last group accordingly
2201          */
2202         if (last_start < data_needed) {
2203                 blk64_t remainder = data_needed - last_start;
2204
2205 #ifdef RESIZE2FS_DEBUG
2206                 if (flags & RESIZE_DEBUG_MIN_CALC)
2207                         printf("Need %llu data blocks in last group\n",
2208                                remainder);
2209 #endif
2210                 /*
2211                  * 50 is a magic number that mkfs/resize uses to see if its
2212                  * even worth making/resizing the fs.  basically you need to
2213                  * have at least 50 blocks in addition to the blocks needed
2214                  * for the metadata in the last group
2215                  */
2216                 if (remainder > 50)
2217                         overhead += remainder;
2218                 else
2219                         overhead += 50;
2220         } else
2221                 overhead += 50;
2222
2223         overhead += fs->super->s_first_data_block;
2224 #ifdef RESIZE2FS_DEBUG
2225         if (flags & RESIZE_DEBUG_MIN_CALC)
2226                 printf("Final size of last group is %lld\n", overhead);
2227 #endif
2228
2229         /*
2230          * since our last group doesn't have to be BLOCKS_PER_GROUP large, we
2231          * only do groups-1, and then add the number of blocks needed to
2232          * handle the group descriptor metadata+data that we need
2233          */
2234         blks_needed = (groups-1) * EXT2_BLOCKS_PER_GROUP(fs->super);
2235         blks_needed += overhead;
2236
2237         /*
2238          * Make sure blks_needed covers the end of the inode table in
2239          * the last block group.
2240          */
2241         overhead = ext2fs_inode_table_loc(fs, groups-1) +
2242                 fs->inode_blocks_per_group;
2243         if (blks_needed < overhead)
2244                 blks_needed = overhead;
2245
2246 #ifdef RESIZE2FS_DEBUG
2247         if (flags & RESIZE_DEBUG_MIN_CALC)
2248                 printf("Estimated blocks needed: %llu\n", blks_needed);
2249 #endif
2250
2251         /*
2252          * If at this point we've already added up more "needed" than
2253          * the current size, just return current size as minimum.
2254          */
2255         if (blks_needed >= ext2fs_blocks_count(fs->super))
2256                 return ext2fs_blocks_count(fs->super);
2257         /*
2258          * We need to reserve a few extra blocks if extents are
2259          * enabled, in case we need to grow the extent tree.  The more
2260          * we shrink the file system, the more space we need.
2261          */
2262         if (fs->super->s_feature_incompat & EXT3_FEATURE_INCOMPAT_EXTENTS) {
2263                 blk64_t safe_margin = (ext2fs_blocks_count(fs->super) -
2264                                        blks_needed)/500;
2265 #ifdef RESIZE2FS_DEBUG
2266                 if (flags & RESIZE_DEBUG_MIN_CALC)
2267                         printf("Extents safety margin: %llu\n", safe_margin);
2268 #endif
2269                 blks_needed += safe_margin;
2270         }
2271
2272         return blks_needed;
2273 }