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 "resize2fs.h"
  37 #include <time.h>
  38
  39 #ifdef __linux__                        /* Kludge for debugging */
  40 #define RESIZE2FS_DEBUG
  41 #endif
  42
  43 static void fix_uninit_block_bitmaps(ext2_filsys fs);
  44 static errcode_t adjust_superblock(ext2_resize_t rfs, blk64_t new_size);
  45 static errcode_t blocks_to_move(ext2_resize_t rfs);
  46 static errcode_t block_mover(ext2_resize_t rfs);
  47 static errcode_t inode_scan_and_fix(ext2_resize_t rfs);
  48 static errcode_t inode_ref_fix(ext2_resize_t rfs);
  49 static errcode_t move_itables(ext2_resize_t rfs);
  50 static errcode_t fix_resize_inode(ext2_filsys fs);
  51 static errcode_t ext2fs_calculate_summary_stats(ext2_filsys fs);
  52 static errcode_t fix_sb_journal_backup(ext2_filsys fs);
  53 static errcode_t mark_table_blocks(ext2_filsys fs,
  54                                    ext2fs_block_bitmap bmap);
  55
  56 /*
  57  * Some helper CPP macros
  58  */
  59 #define IS_BLOCK_BM(fs, i, blk) ((blk) == ext2fs_block_bitmap_loc((fs),(i)))
  60 #define IS_INODE_BM(fs, i, blk) ((blk) == ext2fs_inode_bitmap_loc((fs),(i)))
  61
  62 #define IS_INODE_TB(fs, i, blk) (((blk) >= ext2fs_inode_table_loc((fs), (i))) && \
  63                                  ((blk) < (ext2fs_inode_table_loc((fs), (i)) + \
  64                                            (fs)->inode_blocks_per_group)))
  65
  66 /* Some bigalloc helper macros which are more succint... */
  67 #define B2C(x)  EXT2FS_B2C(fs, (x))
  68 #define C2B(x)  EXT2FS_C2B(fs, (x))
  69 #define EQ_CLSTR(x, y) (B2C(x) == B2C(y))
  70 #define LE_CLSTR(x, y) (B2C(x) <= B2C(y))
  71 #define LT_CLSTR(x, y) (B2C(x) <  B2C(y))
  72 #define GE_CLSTR(x, y) (B2C(x) >= B2C(y))
  73 #define GT_CLSTR(x, y) (B2C(x) >  B2C(y))
  74
  75 static int lazy_itable_init;
  76
  77 /*
  78  * This is the top-level routine which does the dirty deed....
  79  */
  80 errcode_t resize_fs(ext2_filsys fs, blk64_t *new_size, int flags,
  81             errcode_t (*progress)(ext2_resize_t rfs, int pass,
  82                                           unsigned long cur,
  83                                           unsigned long max_val))
  84 {
  85         ext2_resize_t   rfs;
  86         errcode_t       retval;
  87         struct resource_track   rtrack, overall_track;
  88
  89         /*
  90          * Create the data structure
  91          */
  92         retval = ext2fs_get_mem(sizeof(struct ext2_resize_struct), &rfs);
  93         if (retval)
  94                 return retval;
  95
  96         memset(rfs, 0, sizeof(struct ext2_resize_struct));
  97         fs->priv_data = rfs;
  98         rfs->old_fs = fs;
  99         rfs->flags = flags;
 100         rfs->itable_buf  = 0;
 101         rfs->progress = progress;
 102
 103         init_resource_track(&overall_track, "overall resize2fs", fs->io);
 104         init_resource_track(&rtrack, "read_bitmaps", fs->io);
 105         retval = ext2fs_read_bitmaps(fs);
 106         if (retval)
 107                 goto errout;
 108         print_resource_track(rfs, &rtrack, fs->io);
 109
 110         fs->super->s_state |= EXT2_ERROR_FS;
 111         ext2fs_mark_super_dirty(fs);
 112         ext2fs_flush(fs);
 113
 114         init_resource_track(&rtrack, "fix_uninit_block_bitmaps 1", fs->io);
 115         fix_uninit_block_bitmaps(fs);
 116         print_resource_track(rfs, &rtrack, fs->io);
 117         retval = ext2fs_dup_handle(fs, &rfs->new_fs);
 118         if (retval)
 119                 goto errout;
 120
 121         init_resource_track(&rtrack, "adjust_superblock", fs->io);
 122         retval = adjust_superblock(rfs, *new_size);
 123         if (retval)
 124                 goto errout;
 125         print_resource_track(rfs, &rtrack, fs->io);
 126
 127
 128         init_resource_track(&rtrack, "fix_uninit_block_bitmaps 2", fs->io);
 129         fix_uninit_block_bitmaps(rfs->new_fs);
 130         print_resource_track(rfs, &rtrack, fs->io);
 131         /* Clear the block bitmap uninit flag for the last block group */
 132         ext2fs_bg_flags_clear(rfs->new_fs, rfs->new_fs->group_desc_count - 1,
 133                              EXT2_BG_BLOCK_UNINIT);
 134
 135         *new_size = ext2fs_blocks_count(rfs->new_fs->super);
 136
 137         init_resource_track(&rtrack, "blocks_to_move", fs->io);
 138         retval = blocks_to_move(rfs);
 139         if (retval)
 140                 goto errout;
 141         print_resource_track(rfs, &rtrack, fs->io);
 142
 143 #ifdef RESIZE2FS_DEBUG
 144         if (rfs->flags & RESIZE_DEBUG_BMOVE)
 145                 printf("Number of free blocks: %llu/%llu, Needed: %llu\n",
 146                        ext2fs_free_blocks_count(rfs->old_fs->super),
 147                        ext2fs_free_blocks_count(rfs->new_fs->super),
 148                        rfs->needed_blocks);
 149 #endif
 150
 151         init_resource_track(&rtrack, "block_mover", fs->io);
 152         retval = block_mover(rfs);
 153         if (retval)
 154                 goto errout;
 155         print_resource_track(rfs, &rtrack, fs->io);
 156
 157         init_resource_track(&rtrack, "inode_scan_and_fix", fs->io);
 158         retval = inode_scan_and_fix(rfs);
 159         if (retval)
 160                 goto errout;
 161         print_resource_track(rfs, &rtrack, fs->io);
 162
 163         init_resource_track(&rtrack, "inode_ref_fix", fs->io);
 164         retval = inode_ref_fix(rfs);
 165         if (retval)
 166                 goto errout;
 167         print_resource_track(rfs, &rtrack, fs->io);
 168
 169         init_resource_track(&rtrack, "move_itables", fs->io);
 170         retval = move_itables(rfs);
 171         if (retval)
 172                 goto errout;
 173         print_resource_track(rfs, &rtrack, fs->io);
 174
 175         init_resource_track(&rtrack, "calculate_summary_stats", fs->io);
 176         retval = ext2fs_calculate_summary_stats(rfs->new_fs);
 177         if (retval)
 178                 goto errout;
 179         print_resource_track(rfs, &rtrack, fs->io);
 180
 181         init_resource_track(&rtrack, "fix_resize_inode", fs->io);
 182         retval = fix_resize_inode(rfs->new_fs);
 183         if (retval)
 184                 goto errout;
 185         print_resource_track(rfs, &rtrack, fs->io);
 186
 187         init_resource_track(&rtrack, "fix_sb_journal_backup", fs->io);
 188         retval = fix_sb_journal_backup(rfs->new_fs);
 189         if (retval)
 190                 goto errout;
 191         print_resource_track(rfs, &rtrack, fs->io);
 192
 193         rfs->new_fs->super->s_state &= ~EXT2_ERROR_FS;
 194         rfs->new_fs->flags &= ~EXT2_FLAG_MASTER_SB_ONLY;
 195
 196         print_resource_track(rfs, &overall_track, fs->io);
 197         retval = ext2fs_close(rfs->new_fs);
 198         if (retval)
 199                 goto errout;
 200
 201         rfs->flags = flags;
 202
 203         ext2fs_free(rfs->old_fs);
 204         if (rfs->itable_buf)
 205                 ext2fs_free_mem(&rfs->itable_buf);
 206         if (rfs->reserve_blocks)
 207                 ext2fs_free_block_bitmap(rfs->reserve_blocks);
 208         if (rfs->move_blocks)
 209                 ext2fs_free_block_bitmap(rfs->move_blocks);
 210         ext2fs_free_mem(&rfs);
 211
 212         return 0;
 213
 214 errout:
 215         if (rfs->new_fs)
 216                 ext2fs_free(rfs->new_fs);
 217         if (rfs->itable_buf)
 218                 ext2fs_free_mem(&rfs->itable_buf);
 219         ext2fs_free_mem(&rfs);
 220         return retval;
 221 }
 222
 223 /*
 224  * Clean up the bitmaps for unitialized bitmaps
 225  */
 226 static void fix_uninit_block_bitmaps(ext2_filsys fs)
 227 {
 228         blk64_t         blk, lblk;
 229         dgrp_t          g;
 230         int             i;
 231
 232         if (!(EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
 233                                          EXT4_FEATURE_RO_COMPAT_GDT_CSUM)))
 234                 return;
 235
 236         for (g=0; g < fs->group_desc_count; g++) {
 237                 if (!(ext2fs_bg_flags_test(fs, g, EXT2_BG_BLOCK_UNINIT)))
 238                         continue;
 239
 240                 blk = ext2fs_group_first_block2(fs, g);
 241                 lblk = ext2fs_group_last_block2(fs, g);
 242                 ext2fs_unmark_block_bitmap_range2(fs->block_map, blk,
 243                                                   lblk - blk + 1);
 244
 245                 ext2fs_reserve_super_and_bgd(fs, g, fs->block_map);
 246                 ext2fs_mark_block_bitmap2(fs->block_map,
 247                                           ext2fs_block_bitmap_loc(fs, g));
 248                 ext2fs_mark_block_bitmap2(fs->block_map,
 249                                           ext2fs_inode_bitmap_loc(fs, g));
 250                 for (i = 0, blk = ext2fs_inode_table_loc(fs, g);
 251                      i < (unsigned int) fs->inode_blocks_per_group;
 252                      i++, blk++)
 253                         ext2fs_mark_block_bitmap2(fs->block_map, blk);
 254         }
 255 }
 256
 257 /* --------------------------------------------------------------------
 258  *
 259  * Resize processing, phase 1.
 260  *
 261  * In this phase we adjust the in-memory superblock information, and
 262  * initialize any new parts of the inode table.  The new parts of the
 263  * inode table are created in virgin disk space, so we can abort here
 264  * without any side effects.
 265  * --------------------------------------------------------------------
 266  */
 267
 268 /*
 269  * If the group descriptor's bitmap and inode table blocks are valid,
 270  * release them in the new filesystem data structure, and mark them as
 271  * reserved so the old inode table blocks don't get overwritten.
 272  */
 273 static void free_gdp_blocks(ext2_filsys fs,
 274                             ext2fs_block_bitmap reserve_blocks,
 275                             ext2_filsys old_fs,
 276                             dgrp_t group)
 277 {
 278         blk64_t blk;
 279         int     j;
 280
 281         blk = ext2fs_block_bitmap_loc(old_fs, group);
 282         if (blk &&
 283             (blk < ext2fs_blocks_count(fs->super))) {
 284                 ext2fs_block_alloc_stats2(fs, blk, -1);
 285                 ext2fs_mark_block_bitmap2(reserve_blocks, blk);
 286         }
 287
 288         blk = ext2fs_inode_bitmap_loc(old_fs, group);
 289         if (blk &&
 290             (blk < ext2fs_blocks_count(fs->super))) {
 291                 ext2fs_block_alloc_stats2(fs, blk, -1);
 292                 ext2fs_mark_block_bitmap2(reserve_blocks, blk);
 293         }
 294
 295         blk = ext2fs_inode_table_loc(old_fs, group);
 296         if (blk == 0 ||
 297             (blk >= ext2fs_blocks_count(fs->super)))
 298                 return;
 299
 300         for (j = 0;
 301              j < fs->inode_blocks_per_group; j++, blk++) {
 302                 if (blk >= ext2fs_blocks_count(fs->super))
 303                         break;
 304                 ext2fs_block_alloc_stats2(fs, blk, -1);
 305                 ext2fs_mark_block_bitmap2(reserve_blocks, blk);
 306         }
 307 }
 308
 309 /*
 310  * This routine is shared by the online and offline resize routines.
 311  * All of the information which is adjusted in memory is done here.
 312  */
 313 errcode_t adjust_fs_info(ext2_filsys fs, ext2_filsys old_fs,
 314                          ext2fs_block_bitmap reserve_blocks, blk64_t new_size)
 315 {
 316         errcode_t       retval;
 317         blk64_t         overhead = 0;
 318         blk64_t         rem;
 319         blk64_t         blk, group_block;
 320         blk64_t         real_end;
 321         blk64_t         old_numblocks, numblocks, adjblocks;
 322         unsigned long   i, j, old_desc_blocks;
 323         unsigned int    meta_bg, meta_bg_size;
 324         int             has_super, csum_flag;
 325         unsigned long long new_inodes;  /* u64 to check for overflow */
 326         double          percent;
 327
 328         ext2fs_blocks_count_set(fs->super, new_size);
 329
 330 retry:
 331         fs->group_desc_count = ext2fs_div64_ceil(ext2fs_blocks_count(fs->super) -
 332                                        fs->super->s_first_data_block,
 333                                        EXT2_BLOCKS_PER_GROUP(fs->super));
 334         if (fs->group_desc_count == 0)
 335                 return EXT2_ET_TOOSMALL;
 336         fs->desc_blocks = ext2fs_div_ceil(fs->group_desc_count,
 337                                           EXT2_DESC_PER_BLOCK(fs->super));
 338
 339         /*
 340          * Overhead is the number of bookkeeping blocks per group.  It
 341          * includes the superblock backup, the group descriptor
 342          * backups, the inode bitmap, the block bitmap, and the inode
 343          * table.
 344          */
 345         overhead = (int) (2 + fs->inode_blocks_per_group);
 346
 347         if (ext2fs_bg_has_super(fs, fs->group_desc_count - 1))
 348                 overhead += 1 + fs->desc_blocks +
 349                         fs->super->s_reserved_gdt_blocks;
 350
 351         /*
 352          * See if the last group is big enough to support the
 353          * necessary data structures.  If not, we need to get rid of
 354          * it.
 355          */
 356         rem = (ext2fs_blocks_count(fs->super) - fs->super->s_first_data_block) %
 357                 fs->super->s_blocks_per_group;
 358         if ((fs->group_desc_count == 1) && rem && (rem < overhead))
 359                 return EXT2_ET_TOOSMALL;
 360         if ((fs->group_desc_count > 1) && rem && (rem < overhead+50)) {
 361                 ext2fs_blocks_count_set(fs->super,
 362                                         ext2fs_blocks_count(fs->super) - rem);
 363                 goto retry;
 364         }
 365         /*
 366          * Adjust the number of inodes
 367          */
 368         new_inodes =(unsigned long long) fs->super->s_inodes_per_group * fs->group_desc_count;
 369         if (new_inodes > ~0U) {
 370                 fprintf(stderr, _("inodes (%llu) must be less than %u"),
 371                                    new_inodes, ~0U);
 372                 return EXT2_ET_TOO_MANY_INODES;
 373         }
 374         fs->super->s_inodes_count = fs->super->s_inodes_per_group *
 375                 fs->group_desc_count;
 376
 377         /*
 378          * Adjust the number of free blocks
 379          */
 380         blk = ext2fs_blocks_count(old_fs->super);
 381         if (blk > ext2fs_blocks_count(fs->super))
 382                 ext2fs_free_blocks_count_set(fs->super,
 383                         ext2fs_free_blocks_count(fs->super) -
 384                         (blk - ext2fs_blocks_count(fs->super)));
 385         else
 386                 ext2fs_free_blocks_count_set(fs->super,
 387                         ext2fs_free_blocks_count(fs->super) +
 388                         (ext2fs_blocks_count(fs->super) - blk));
 389
 390         /*
 391          * Adjust the number of reserved blocks
 392          */
 393         percent = (ext2fs_r_blocks_count(old_fs->super) * 100.0) /
 394                 ext2fs_blocks_count(old_fs->super);
 395         ext2fs_r_blocks_count_set(fs->super,
 396                                   (percent * ext2fs_blocks_count(fs->super) /
 397                                    100.0));
 398
 399         /*
 400          * Adjust the bitmaps for size
 401          */
 402         retval = ext2fs_resize_inode_bitmap2(fs->super->s_inodes_count,
 403                                             fs->super->s_inodes_count,
 404                                             fs->inode_map);
 405         if (retval) goto errout;
 406
 407         real_end = (((blk64_t) EXT2_BLOCKS_PER_GROUP(fs->super) *
 408                      fs->group_desc_count)) - 1 +
 409                 fs->super->s_first_data_block;
 410         retval = ext2fs_resize_block_bitmap2(new_size - 1,
 411                                              real_end, fs->block_map);
 412         if (retval) goto errout;
 413
 414         /*
 415          * If we are growing the file system, also grow the size of
 416          * the reserve_blocks bitmap
 417          */
 418         if (reserve_blocks && new_size > ext2fs_blocks_count(old_fs->super)) {
 419                 retval = ext2fs_resize_block_bitmap2(new_size - 1,
 420                                                      real_end, reserve_blocks);
 421                 if (retval) goto errout;
 422         }
 423
 424         /*
 425          * Reallocate the group descriptors as necessary.
 426          */
 427         if (old_fs->desc_blocks != fs->desc_blocks) {
 428                 retval = ext2fs_resize_mem(old_fs->desc_blocks *
 429                                            fs->blocksize,
 430                                            fs->desc_blocks * fs->blocksize,
 431                                            &fs->group_desc);
 432                 if (retval)
 433                         goto errout;
 434                 if (fs->desc_blocks > old_fs->desc_blocks)
 435                         memset((char *) fs->group_desc +
 436                                (old_fs->desc_blocks * fs->blocksize), 0,
 437                                (fs->desc_blocks - old_fs->desc_blocks) *
 438                                fs->blocksize);
 439         }
 440
 441         /*
 442          * If the resize_inode feature is set, and we are changing the
 443          * number of descriptor blocks, then adjust
 444          * s_reserved_gdt_blocks if possible to avoid needing to move
 445          * the inode table either now or in the future.
 446          */
 447         if ((fs->super->s_feature_compat &
 448              EXT2_FEATURE_COMPAT_RESIZE_INODE) &&
 449             (old_fs->desc_blocks != fs->desc_blocks)) {
 450                 int new;
 451
 452                 new = ((int) fs->super->s_reserved_gdt_blocks) +
 453                         (old_fs->desc_blocks - fs->desc_blocks);
 454                 if (new < 0)
 455                         new = 0;
 456                 if (new > (int) fs->blocksize/4)
 457                         new = fs->blocksize/4;
 458                 fs->super->s_reserved_gdt_blocks = new;
 459         }
 460
 461         /*
 462          * If we are shrinking the number of block groups, we're done
 463          * and can exit now.
 464          */
 465         if (old_fs->group_desc_count > fs->group_desc_count) {
 466                 /*
 467                  * Check the block groups that we are chopping off
 468                  * and free any blocks associated with their metadata
 469                  */
 470                 for (i = fs->group_desc_count;
 471                      i < old_fs->group_desc_count; i++)
 472                         free_gdp_blocks(fs, reserve_blocks, old_fs, i);
 473                 retval = 0;
 474                 goto errout;
 475         }
 476
 477         /*
 478          * Fix the count of the last (old) block group
 479          */
 480         old_numblocks = (ext2fs_blocks_count(old_fs->super) -
 481                          old_fs->super->s_first_data_block) %
 482                                  old_fs->super->s_blocks_per_group;
 483         if (!old_numblocks)
 484                 old_numblocks = old_fs->super->s_blocks_per_group;
 485         if (old_fs->group_desc_count == fs->group_desc_count) {
 486                 numblocks = (ext2fs_blocks_count(fs->super) -
 487                              fs->super->s_first_data_block) %
 488                         fs->super->s_blocks_per_group;
 489                 if (!numblocks)
 490                         numblocks = fs->super->s_blocks_per_group;
 491         } else
 492                 numblocks = fs->super->s_blocks_per_group;
 493         i = old_fs->group_desc_count - 1;
 494         ext2fs_bg_free_blocks_count_set(fs, i, ext2fs_bg_free_blocks_count(fs, i) + (numblocks - old_numblocks));
 495         ext2fs_group_desc_csum_set(fs, i);
 496
 497         /*
 498          * If the number of block groups is staying the same, we're
 499          * done and can exit now.  (If the number block groups is
 500          * shrinking, we had exited earlier.)
 501          */
 502         if (old_fs->group_desc_count >= fs->group_desc_count) {
 503                 retval = 0;
 504                 goto errout;
 505         }
 506
 507         /*
 508          * Initialize the new block group descriptors
 509          */
 510         group_block = ext2fs_group_first_block2(fs,
 511                                                 old_fs->group_desc_count);
 512         csum_flag = EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
 513                                                EXT4_FEATURE_RO_COMPAT_GDT_CSUM);
 514         if (access("/sys/fs/ext4/features/lazy_itable_init", F_OK) == 0)
 515                 lazy_itable_init = 1;
 516         if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
 517                 old_desc_blocks = fs->super->s_first_meta_bg;
 518         else
 519                 old_desc_blocks = fs->desc_blocks +
 520                         fs->super->s_reserved_gdt_blocks;
 521
 522         /*
 523          * If we changed the number of block_group descriptor blocks,
 524          * we need to make sure they are all marked as reserved in the
 525          * file systems's block allocation map.
 526          */
 527         for (i = 0; i < old_fs->group_desc_count; i++)
 528                 ext2fs_reserve_super_and_bgd(fs, i, fs->block_map);
 529
 530         for (i = old_fs->group_desc_count;
 531              i < fs->group_desc_count; i++) {
 532                 memset(ext2fs_group_desc(fs, fs->group_desc, i), 0,
 533                        sizeof(struct ext2_group_desc));
 534                 adjblocks = 0;
 535
 536                 ext2fs_bg_flags_zap(fs, i);
 537                 if (csum_flag) {
 538                         ext2fs_bg_flags_set(fs, i, EXT2_BG_INODE_UNINIT);
 539                         if (!lazy_itable_init)
 540                                 ext2fs_bg_flags_set(fs, i,
 541                                                     EXT2_BG_INODE_ZEROED);
 542                         ext2fs_bg_itable_unused_set(fs, i,
 543                                         fs->super->s_inodes_per_group);
 544                 }
 545
 546                 numblocks = ext2fs_group_blocks_count(fs, i);
 547                 if ((i < fs->group_desc_count - 1) && csum_flag)
 548                         ext2fs_bg_flags_set(fs, i, EXT2_BG_BLOCK_UNINIT);
 549
 550                 has_super = ext2fs_bg_has_super(fs, i);
 551                 if (has_super) {
 552                         ext2fs_block_alloc_stats2(fs, group_block, +1);
 553                         adjblocks++;
 554                 }
 555                 meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
 556                 meta_bg = i / meta_bg_size;
 557                 if (!(fs->super->s_feature_incompat &
 558                       EXT2_FEATURE_INCOMPAT_META_BG) ||
 559                     (meta_bg < fs->super->s_first_meta_bg)) {
 560                         if (has_super) {
 561                                 for (j=0; j < old_desc_blocks; j++)
 562                                         ext2fs_block_alloc_stats2(fs,
 563                                                  group_block + 1 + j, +1);
 564                                 adjblocks += old_desc_blocks;
 565                         }
 566                 } else {
 567                         if (has_super)
 568                                 has_super = 1;
 569                         if (((i % meta_bg_size) == 0) ||
 570                             ((i % meta_bg_size) == 1) ||
 571                             ((i % meta_bg_size) == (meta_bg_size-1)))
 572                                 ext2fs_block_alloc_stats2(fs,
 573                                                  group_block + has_super, +1);
 574                 }
 575
 576                 adjblocks += 2 + fs->inode_blocks_per_group;
 577
 578                 numblocks -= adjblocks;
 579                 ext2fs_free_blocks_count_set(fs->super,
 580                              ext2fs_free_blocks_count(fs->super) - adjblocks);
 581                 fs->super->s_free_inodes_count +=
 582                         fs->super->s_inodes_per_group;
 583                 ext2fs_bg_free_blocks_count_set(fs, i, numblocks);
 584                 ext2fs_bg_free_inodes_count_set(fs, i,
 585                                                 fs->super->s_inodes_per_group);
 586                 ext2fs_bg_used_dirs_count_set(fs, i, 0);
 587                 ext2fs_group_desc_csum_set(fs, i);
 588
 589                 retval = ext2fs_allocate_group_table(fs, i, 0);
 590                 if (retval) goto errout;
 591
 592                 group_block += fs->super->s_blocks_per_group;
 593         }
 594         retval = 0;
 595
 596         /*
 597          * Mark all of the metadata blocks as reserved so they won't
 598          * get allocated by the call to ext2fs_allocate_group_table()
 599          * in blocks_to_move(), where we allocate new blocks to
 600          * replace those allocation bitmap and inode table blocks
 601          * which have to get relocated to make space for an increased
 602          * number of the block group descriptors.
 603          */
 604         if (reserve_blocks)
 605                 mark_table_blocks(fs, reserve_blocks);
 606
 607 errout:
 608         return (retval);
 609 }
 610
 611 /*
 612  * This routine adjusts the superblock and other data structures, both
 613  * in disk as well as in memory...
 614  */
 615 static errcode_t adjust_superblock(ext2_resize_t rfs, blk64_t new_size)
 616 {
 617         ext2_filsys fs;
 618         int             adj = 0;
 619         errcode_t       retval;
 620         blk64_t         group_block;
 621         unsigned long   i;
 622         unsigned long   max_group;
 623
 624         fs = rfs->new_fs;
 625         ext2fs_mark_super_dirty(fs);
 626         ext2fs_mark_bb_dirty(fs);
 627         ext2fs_mark_ib_dirty(fs);
 628
 629         retval = ext2fs_allocate_block_bitmap(fs, _("reserved blocks"),
 630                                               &rfs->reserve_blocks);
 631         if (retval)
 632                 return retval;
 633
 634         retval = adjust_fs_info(fs, rfs->old_fs, rfs->reserve_blocks, new_size);
 635         if (retval)
 636                 goto errout;
 637
 638         /*
 639          * Check to make sure there are enough inodes
 640          */
 641         if ((rfs->old_fs->super->s_inodes_count -
 642              rfs->old_fs->super->s_free_inodes_count) >
 643             rfs->new_fs->super->s_inodes_count) {
 644                 retval = ENOSPC;
 645                 goto errout;
 646         }
 647
 648         /*
 649          * If we are shrinking the number block groups, we're done and
 650          * can exit now.
 651          */
 652         if (rfs->old_fs->group_desc_count > fs->group_desc_count) {
 653                 retval = 0;
 654                 goto errout;
 655         }
 656
 657         /*
 658          * If the number of block groups is staying the same, we're
 659          * done and can exit now.  (If the number block groups is
 660          * shrinking, we had exited earlier.)
 661          */
 662         if (rfs->old_fs->group_desc_count >= fs->group_desc_count) {
 663                 retval = 0;
 664                 goto errout;
 665         }
 666
 667         /*
 668          * If we are using uninit_bg (aka GDT_CSUM) and the kernel
 669          * supports lazy inode initialization, we can skip
 670          * initializing the inode table.
 671          */
 672         if (lazy_itable_init &&
 673             EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
 674                                        EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
 675                 retval = 0;
 676                 goto errout;
 677         }
 678
 679         /*
 680          * Initialize the inode table
 681          */
 682         retval = ext2fs_get_array(fs->blocksize, fs->inode_blocks_per_group,
 683                                 &rfs->itable_buf);
 684         if (retval)
 685                 goto errout;
 686
 687         memset(rfs->itable_buf, 0, fs->blocksize * fs->inode_blocks_per_group);
 688         group_block = ext2fs_group_first_block2(fs,
 689                                                 rfs->old_fs->group_desc_count);
 690         adj = rfs->old_fs->group_desc_count;
 691         max_group = fs->group_desc_count - adj;
 692         if (rfs->progress) {
 693                 retval = rfs->progress(rfs, E2_RSZ_EXTEND_ITABLE_PASS,
 694                                        0, max_group);
 695                 if (retval)
 696                         goto errout;
 697         }
 698         for (i = rfs->old_fs->group_desc_count;
 699              i < fs->group_desc_count; i++) {
 700                 /*
 701                  * Write out the new inode table
 702                  */
 703                 retval = io_channel_write_blk64(fs->io,
 704                                                 ext2fs_inode_table_loc(fs, i),
 705                                                 fs->inode_blocks_per_group,
 706                                                 rfs->itable_buf);
 707                 if (retval) goto errout;
 708
 709                 io_channel_flush(fs->io);
 710                 if (rfs->progress) {
 711                         retval = rfs->progress(rfs, E2_RSZ_EXTEND_ITABLE_PASS,
 712                                                i - adj + 1, max_group);
 713                         if (retval)
 714                                 goto errout;
 715                 }
 716                 group_block += fs->super->s_blocks_per_group;
 717         }
 718         io_channel_flush(fs->io);
 719         retval = 0;
 720
 721 errout:
 722         return retval;
 723 }
 724
 725 /* --------------------------------------------------------------------
 726  *
 727  * Resize processing, phase 2.
 728  *
 729  * In this phase we adjust determine which blocks need to be moved, in
 730  * blocks_to_move().  We then copy the blocks to their ultimate new
 731  * destinations using block_mover().  Since we are copying blocks to
 732  * their new locations, again during this pass we can abort without
 733  * any problems.
 734  * --------------------------------------------------------------------
 735  */
 736
 737 /*
 738  * This helper function creates a block bitmap with all of the
 739  * filesystem meta-data blocks.
 740  */
 741 static errcode_t mark_table_blocks(ext2_filsys fs,
 742                                    ext2fs_block_bitmap bmap)
 743 {
 744         dgrp_t                  i;
 745         blk64_t                 blk;
 746
 747         for (i = 0; i < fs->group_desc_count; i++) {
 748                 ext2fs_reserve_super_and_bgd(fs, i, bmap);
 749
 750                 /*
 751                  * Mark the blocks used for the inode table
 752                  */
 753                 blk = ext2fs_inode_table_loc(fs, i);
 754                 if (blk)
 755                         ext2fs_mark_block_bitmap_range2(bmap, blk,
 756                                                 fs->inode_blocks_per_group);
 757
 758                 /*
 759                  * Mark block used for the block bitmap
 760                  */
 761                 blk = ext2fs_block_bitmap_loc(fs, i);
 762                 if (blk)
 763                         ext2fs_mark_block_bitmap2(bmap, blk);
 764
 765                 /*
 766                  * Mark block used for the inode bitmap
 767                  */
 768                 blk = ext2fs_inode_bitmap_loc(fs, i);
 769                 if (blk)
 770                         ext2fs_mark_block_bitmap2(bmap, blk);
 771         }
 772         return 0;
 773 }
 774
 775 /*
 776  * This function checks to see if a particular block (either a
 777  * superblock or a block group descriptor) overlaps with an inode or
 778  * block bitmap block, or with the inode table.
 779  */
 780 static void mark_fs_metablock(ext2_resize_t rfs,
 781                               ext2fs_block_bitmap meta_bmap,
 782                               int group, blk64_t blk)
 783 {
 784         ext2_filsys     fs = rfs->new_fs;
 785
 786         ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
 787         ext2fs_block_alloc_stats2(fs, blk, +1);
 788
 789         /*
 790          * Check to see if we overlap with the inode or block bitmap,
 791          * or the inode tables.  If not, and the block is in use, then
 792          * mark it as a block to be moved.
 793          */
 794         if (IS_BLOCK_BM(fs, group, blk)) {
 795                 ext2fs_block_bitmap_loc_set(fs, group, 0);
 796                 rfs->needed_blocks++;
 797                 return;
 798         }
 799         if (IS_INODE_BM(fs, group, blk)) {
 800                 ext2fs_inode_bitmap_loc_set(fs, group, 0);
 801                 rfs->needed_blocks++;
 802                 return;
 803         }
 804         if (IS_INODE_TB(fs, group, blk)) {
 805                 ext2fs_inode_table_loc_set(fs, group, 0);
 806                 rfs->needed_blocks++;
 807                 return;
 808         }
 809         if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_FLEX_BG) {
 810                 dgrp_t i;
 811
 812                 for (i=0; i < rfs->old_fs->group_desc_count; i++) {
 813                         if (IS_BLOCK_BM(fs, i, blk)) {
 814                                 ext2fs_block_bitmap_loc_set(fs, i, 0);
 815                                 rfs->needed_blocks++;
 816                                 return;
 817                         }
 818                         if (IS_INODE_BM(fs, i, blk)) {
 819                                 ext2fs_inode_bitmap_loc_set(fs, i, 0);
 820                                 rfs->needed_blocks++;
 821                                 return;
 822                         }
 823                         if (IS_INODE_TB(fs, i, blk)) {
 824                                 ext2fs_inode_table_loc_set(fs, i, 0);
 825                                 rfs->needed_blocks++;
 826                                 return;
 827                         }
 828                 }
 829         }
 830         if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
 831                                        EXT4_FEATURE_RO_COMPAT_GDT_CSUM) &&
 832                    (ext2fs_bg_flags_test(fs, group, EXT2_BG_BLOCK_UNINIT))) {
 833                 /*
 834                  * If the block bitmap is uninitialized, which means
 835                  * nothing other than standard metadata in use.
 836                  */
 837                 return;
 838         } else if (ext2fs_test_block_bitmap2(rfs->old_fs->block_map, blk) &&
 839                    !ext2fs_test_block_bitmap2(meta_bmap, blk)) {
 840                 ext2fs_mark_block_bitmap2(rfs->move_blocks, blk);
 841                 rfs->needed_blocks++;
 842         }
 843 }
 844
 845
 846 /*
 847  * This routine marks and unmarks reserved blocks in the new block
 848  * bitmap.  It also determines which blocks need to be moved and
 849  * places this information into the move_blocks bitmap.
 850  */
 851 static errcode_t blocks_to_move(ext2_resize_t rfs)
 852 {
 853         int             j, has_super;
 854         dgrp_t          i, max_groups, g;
 855         blk64_t         blk, group_blk;
 856         blk64_t         old_blocks, new_blocks;
 857         blk64_t         new_size;
 858         unsigned int    meta_bg, meta_bg_size;
 859         errcode_t       retval;
 860         ext2_filsys     fs, old_fs;
 861         ext2fs_block_bitmap     meta_bmap;
 862         int             flex_bg;
 863
 864         fs = rfs->new_fs;
 865         old_fs = rfs->old_fs;
 866         if (ext2fs_blocks_count(old_fs->super) > ext2fs_blocks_count(fs->super))
 867                 fs = rfs->old_fs;
 868
 869         retval = ext2fs_allocate_block_bitmap(fs, _("blocks to be moved"),
 870                                               &rfs->move_blocks);
 871         if (retval)
 872                 return retval;
 873
 874         retval = ext2fs_allocate_block_bitmap(fs, _("meta-data blocks"),
 875                                               &meta_bmap);
 876         if (retval)
 877                 return retval;
 878
 879         retval = mark_table_blocks(old_fs, meta_bmap);
 880         if (retval)
 881                 return retval;
 882
 883         fs = rfs->new_fs;
 884
 885         /*
 886          * If we're shrinking the filesystem, we need to move any
 887          * group's metadata blocks (either allocation bitmaps or the
 888          * inode table) which are beyond the end of the new
 889          * filesystem.
 890          */
 891         new_size = ext2fs_blocks_count(fs->super);
 892         if (new_size < ext2fs_blocks_count(old_fs->super)) {
 893                 for (g = 0; g < fs->group_desc_count; g++) {
 894                         int realloc = 0;
 895                         /*
 896                          * ext2fs_allocate_group_table will re-allocate any
 897                          * metadata blocks whose location is set to zero.
 898                          */
 899                         if (ext2fs_block_bitmap_loc(fs, g) >= new_size) {
 900                                 ext2fs_block_bitmap_loc_set(fs, g, 0);
 901                                 realloc = 1;
 902                         }
 903                         if (ext2fs_inode_bitmap_loc(fs, g) >= new_size) {
 904                                 ext2fs_inode_bitmap_loc_set(fs, g, 0);
 905                                 realloc = 1;
 906                         }
 907                         if ((ext2fs_inode_table_loc(fs, g) +
 908                              fs->inode_blocks_per_group) > new_size) {
 909                                 ext2fs_inode_table_loc_set(fs, g, 0);
 910                                 realloc = 1;
 911                         }
 912
 913                         if (realloc) {
 914                                 retval = ext2fs_allocate_group_table(fs, g, 0);
 915                                 if (retval)
 916                                         return retval;
 917                         }
 918                 }
 919         }
 920
 921         /*
 922          * If we're shrinking the filesystem, we need to move all of
 923          * the blocks that don't fit any more
 924          */
 925         for (blk = ext2fs_blocks_count(fs->super);
 926              blk < ext2fs_blocks_count(old_fs->super); blk++) {
 927                 g = ext2fs_group_of_blk2(fs, blk);
 928                 if (EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
 929                                                EXT4_FEATURE_RO_COMPAT_GDT_CSUM) &&
 930                     ext2fs_bg_flags_test(old_fs, g, EXT2_BG_BLOCK_UNINIT)) {
 931                         /*
 932                          * The block bitmap is uninitialized, so skip
 933                          * to the next block group.
 934                          */
 935                         blk = ext2fs_group_first_block2(fs, g+1) - 1;
 936                         continue;
 937                 }
 938                 if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
 939                     !ext2fs_test_block_bitmap2(meta_bmap, blk)) {
 940                         ext2fs_mark_block_bitmap2(rfs->move_blocks, blk);
 941                         rfs->needed_blocks++;
 942                 }
 943                 ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
 944         }
 945
 946         if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG) {
 947                 old_blocks = old_fs->super->s_first_meta_bg;
 948                 new_blocks = fs->super->s_first_meta_bg;
 949         } else {
 950                 old_blocks = old_fs->desc_blocks + old_fs->super->s_reserved_gdt_blocks;
 951                 new_blocks = fs->desc_blocks + fs->super->s_reserved_gdt_blocks;
 952         }
 953
 954         if (old_blocks == new_blocks) {
 955                 retval = 0;
 956                 goto errout;
 957         }
 958
 959         max_groups = fs->group_desc_count;
 960         if (max_groups > old_fs->group_desc_count)
 961                 max_groups = old_fs->group_desc_count;
 962         group_blk = old_fs->super->s_first_data_block;
 963         /*
 964          * If we're reducing the number of descriptor blocks, this
 965          * makes life easy.  :-)   We just have to mark some extra
 966          * blocks as free.
 967          */
 968         if (old_blocks > new_blocks) {
 969                 for (i = 0; i < max_groups; i++) {
 970                         if (!ext2fs_bg_has_super(fs, i)) {
 971                                 group_blk += fs->super->s_blocks_per_group;
 972                                 continue;
 973                         }
 974                         for (blk = group_blk+1+new_blocks;
 975                              blk < group_blk+1+old_blocks; blk++) {
 976                                 ext2fs_block_alloc_stats2(fs, blk, -1);
 977                                 rfs->needed_blocks--;
 978                         }
 979                         group_blk += fs->super->s_blocks_per_group;
 980                 }
 981                 retval = 0;
 982                 goto errout;
 983         }
 984         /*
 985          * If we're increasing the number of descriptor blocks, life
 986          * gets interesting....
 987          */
 988         meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
 989         flex_bg = fs->super->s_feature_incompat &
 990                 EXT4_FEATURE_INCOMPAT_FLEX_BG;
 991         /* first reserve all of the existing fs meta blocks */
 992         for (i = 0; i < max_groups; i++) {
 993                 has_super = ext2fs_bg_has_super(fs, i);
 994                 if (has_super)
 995                         mark_fs_metablock(rfs, meta_bmap, i, group_blk);
 996
 997                 meta_bg = i / meta_bg_size;
 998                 if (!(fs->super->s_feature_incompat &
 999                       EXT2_FEATURE_INCOMPAT_META_BG) ||
1000                     (meta_bg < fs->super->s_first_meta_bg)) {
1001                         if (has_super) {
1002                                 for (blk = group_blk+1;
1003                                      blk < group_blk + 1 + new_blocks; blk++)
1004                                         mark_fs_metablock(rfs, meta_bmap,
1005                                                           i, blk);
1006                         }
1007                 } else {
1008                         if (has_super)
1009                                 has_super = 1;
1010                         if (((i % meta_bg_size) == 0) ||
1011                             ((i % meta_bg_size) == 1) ||
1012                             ((i % meta_bg_size) == (meta_bg_size-1)))
1013                                 mark_fs_metablock(rfs, meta_bmap, i,
1014                                                   group_blk + has_super);
1015                 }
1016
1017                 /*
1018                  * Reserve the existing meta blocks that we know
1019                  * aren't to be moved.
1020                  *
1021                  * For flex_bg file systems, in order to avoid
1022                  * overwriting fs metadata (especially inode table
1023                  * blocks) belonging to a different block group when
1024                  * we are relocating the inode tables, we need to
1025                  * reserve all existing fs metadata blocks.
1026                  */
1027                 if (ext2fs_block_bitmap_loc(fs, i))
1028                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
1029                                  ext2fs_block_bitmap_loc(fs, i));
1030                 else if (flex_bg && i < old_fs->group_desc_count)
1031                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
1032                                  ext2fs_block_bitmap_loc(old_fs, i));
1033
1034                 if (ext2fs_inode_bitmap_loc(fs, i))
1035                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
1036                                  ext2fs_inode_bitmap_loc(fs, i));
1037                 else if (flex_bg && i < old_fs->group_desc_count)
1038                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
1039                                  ext2fs_inode_bitmap_loc(old_fs, i));
1040
1041                 if (ext2fs_inode_table_loc(fs, i))
1042                         ext2fs_mark_block_bitmap_range2(rfs->reserve_blocks,
1043                                         ext2fs_inode_table_loc(fs, i),
1044                                         fs->inode_blocks_per_group);
1045                 else if (flex_bg && i < old_fs->group_desc_count)
1046                         ext2fs_mark_block_bitmap_range2(rfs->reserve_blocks,
1047                                         ext2fs_inode_table_loc(old_fs, i),
1048                                         old_fs->inode_blocks_per_group);
1049
1050                 group_blk += rfs->new_fs->super->s_blocks_per_group;
1051         }
1052
1053         /* Allocate the missing data structures */
1054         for (i = 0; i < max_groups; i++) {
1055                 if (ext2fs_inode_table_loc(fs, i) &&
1056                     ext2fs_inode_bitmap_loc(fs, i) &&
1057                     ext2fs_block_bitmap_loc(fs, i))
1058                         continue;
1059
1060                 retval = ext2fs_allocate_group_table(fs, i,
1061                                                      rfs->reserve_blocks);
1062                 if (retval)
1063                         goto errout;
1064
1065                 /*
1066                  * For those structures that have changed, we need to
1067                  * do bookkeepping.
1068                  */
1069                 if (ext2fs_block_bitmap_loc(old_fs, i) !=
1070                     (blk = ext2fs_block_bitmap_loc(fs, i))) {
1071                         ext2fs_block_alloc_stats2(fs, blk, +1);
1072                         if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
1073                             !ext2fs_test_block_bitmap2(meta_bmap, blk))
1074                                 ext2fs_mark_block_bitmap2(rfs->move_blocks,
1075                                                          blk);
1076                 }
1077                 if (ext2fs_inode_bitmap_loc(old_fs, i) !=
1078                     (blk = ext2fs_inode_bitmap_loc(fs, i))) {
1079                         ext2fs_block_alloc_stats2(fs, blk, +1);
1080                         if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
1081                             !ext2fs_test_block_bitmap2(meta_bmap, blk))
1082                                 ext2fs_mark_block_bitmap2(rfs->move_blocks,
1083                                                          blk);
1084                 }
1085
1086                 /*
1087                  * The inode table, if we need to relocate it, is
1088                  * handled specially.  We have to reserve the blocks
1089                  * for both the old and the new inode table, since we
1090                  * can't have the inode table be destroyed during the
1091                  * block relocation phase.
1092                  */
1093                 if (ext2fs_inode_table_loc(fs, i) == ext2fs_inode_table_loc(old_fs, i))
1094                         continue;       /* inode table not moved */
1095
1096                 rfs->needed_blocks += fs->inode_blocks_per_group;
1097
1098                 /*
1099                  * Mark the new inode table as in use in the new block
1100                  * allocation bitmap, and move any blocks that might
1101                  * be necessary.
1102                  */
1103                 for (blk = ext2fs_inode_table_loc(fs, i), j=0;
1104                      j < fs->inode_blocks_per_group ; j++, blk++) {
1105                         ext2fs_block_alloc_stats2(fs, blk, +1);
1106                         if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
1107                             !ext2fs_test_block_bitmap2(meta_bmap, blk))
1108                                 ext2fs_mark_block_bitmap2(rfs->move_blocks,
1109                                                          blk);
1110                 }
1111
1112                 /*
1113                  * Make sure the old inode table is reserved in the
1114                  * block reservation bitmap.
1115                  */
1116                 for (blk = ext2fs_inode_table_loc(rfs->old_fs, i), j=0;
1117                      j < fs->inode_blocks_per_group ; j++, blk++)
1118                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
1119         }
1120         retval = 0;
1121
1122 errout:
1123         if (meta_bmap)
1124                 ext2fs_free_block_bitmap(meta_bmap);
1125
1126         return retval;
1127 }
1128
1129 /*
1130  * This helper function tries to allocate a new block.  We try to
1131  * avoid hitting the original group descriptor blocks at least at
1132  * first, since we want to make it possible to recover from a badly
1133  * aborted resize operation as much as possible.
1134  *
1135  * In the future, I may further modify this routine to balance out
1136  * where we get the new blocks across the various block groups.
1137  * Ideally we would allocate blocks that corresponded with the block
1138  * group of the containing inode, and keep contiguous blocks
1139  * together.  However, this very difficult to do efficiently, since we
1140  * don't have the necessary information up front.
1141  */
1142
1143 #define AVOID_OLD       1
1144 #define DESPERATION     2
1145
1146 static void init_block_alloc(ext2_resize_t rfs)
1147 {
1148         rfs->alloc_state = AVOID_OLD;
1149         rfs->new_blk = rfs->new_fs->super->s_first_data_block;
1150 #if 0
1151         /* HACK for testing */
1152         if (ext2fs_blocks_count(rfs->new_fs->super) >
1153             ext2fs_blocks_count(rfs->old_fs->super))
1154                 rfs->new_blk = ext2fs_blocks_count(rfs->old_fs->super);
1155 #endif
1156 }
1157
1158 static blk64_t get_new_block(ext2_resize_t rfs)
1159 {
1160         ext2_filsys     fs = rfs->new_fs;
1161
1162         while (1) {
1163                 if (rfs->new_blk >= ext2fs_blocks_count(fs->super)) {
1164                         if (rfs->alloc_state == DESPERATION)
1165                                 return 0;
1166
1167 #ifdef RESIZE2FS_DEBUG
1168                         if (rfs->flags & RESIZE_DEBUG_BMOVE)
1169                                 printf("Going into desperation mode "
1170                                        "for block allocations\n");
1171 #endif
1172                         rfs->alloc_state = DESPERATION;
1173                         rfs->new_blk = fs->super->s_first_data_block;
1174                         continue;
1175                 }
1176                 if (ext2fs_test_block_bitmap2(fs->block_map, rfs->new_blk) ||
1177                     ext2fs_test_block_bitmap2(rfs->reserve_blocks,
1178                                              rfs->new_blk) ||
1179                     ((rfs->alloc_state == AVOID_OLD) &&
1180                      (rfs->new_blk < ext2fs_blocks_count(rfs->old_fs->super)) &&
1181                      ext2fs_test_block_bitmap2(rfs->old_fs->block_map,
1182                                               rfs->new_blk))) {
1183                         rfs->new_blk++;
1184                         continue;
1185                 }
1186                 return rfs->new_blk;
1187         }
1188 }
1189
1190 static errcode_t resize2fs_get_alloc_block(ext2_filsys fs, blk64_t goal,
1191                                            blk64_t *ret)
1192 {
1193         ext2_resize_t rfs = (ext2_resize_t) fs->priv_data;
1194         blk64_t blk;
1195
1196         blk = get_new_block(rfs);
1197         if (!blk)
1198                 return ENOSPC;
1199
1200 #ifdef RESIZE2FS_DEBUG
1201         if (rfs->flags & 0xF)
1202                 printf("get_alloc_block allocating %llu\n", blk);
1203 #endif
1204
1205         ext2fs_mark_block_bitmap2(rfs->old_fs->block_map, blk);
1206         ext2fs_mark_block_bitmap2(rfs->new_fs->block_map, blk);
1207         *ret = (blk64_t) blk;
1208         return 0;
1209 }
1210
1211 static errcode_t block_mover(ext2_resize_t rfs)
1212 {
1213         blk64_t                 blk, old_blk, new_blk;
1214         ext2_filsys             fs = rfs->new_fs;
1215         ext2_filsys             old_fs = rfs->old_fs;
1216         errcode_t               retval;
1217         __u64                   size;
1218         int                     c;
1219         int                     to_move, moved;
1220         ext2_badblocks_list     badblock_list = 0;
1221         int                     bb_modified = 0;
1222
1223         fs->get_alloc_block = resize2fs_get_alloc_block;
1224         old_fs->get_alloc_block = resize2fs_get_alloc_block;
1225
1226         retval = ext2fs_read_bb_inode(old_fs, &badblock_list);
1227         if (retval)
1228                 return retval;
1229
1230         new_blk = fs->super->s_first_data_block;
1231         if (!rfs->itable_buf) {
1232                 retval = ext2fs_get_array(fs->blocksize,
1233                                         fs->inode_blocks_per_group,
1234                                         &rfs->itable_buf);
1235                 if (retval)
1236                         return retval;
1237         }
1238         retval = ext2fs_create_extent_table(&rfs->bmap, 0);
1239         if (retval)
1240                 return retval;
1241
1242         /*
1243          * The first step is to figure out where all of the blocks
1244          * will go.
1245          */
1246         to_move = moved = 0;
1247         init_block_alloc(rfs);
1248         for (blk = B2C(old_fs->super->s_first_data_block);
1249              blk < ext2fs_blocks_count(old_fs->super);
1250              blk += EXT2FS_CLUSTER_RATIO(fs)) {
1251                 if (!ext2fs_test_block_bitmap2(old_fs->block_map, blk))
1252                         continue;
1253                 if (!ext2fs_test_block_bitmap2(rfs->move_blocks, blk))
1254                         continue;
1255                 if (ext2fs_badblocks_list_test(badblock_list, blk)) {
1256                         ext2fs_badblocks_list_del(badblock_list, blk);
1257                         bb_modified++;
1258                         continue;
1259                 }
1260
1261                 new_blk = get_new_block(rfs);
1262                 if (!new_blk) {
1263                         retval = ENOSPC;
1264                         goto errout;
1265                 }
1266                 ext2fs_block_alloc_stats2(fs, new_blk, +1);
1267                 ext2fs_add_extent_entry(rfs->bmap, B2C(blk), B2C(new_blk));
1268                 to_move++;
1269         }
1270
1271         if (to_move == 0) {
1272                 if (rfs->bmap) {
1273                         ext2fs_free_extent_table(rfs->bmap);
1274                         rfs->bmap = 0;
1275                 }
1276                 retval = 0;
1277                 goto errout;
1278         }
1279
1280         /*
1281          * Step two is to actually move the blocks
1282          */
1283         retval =  ext2fs_iterate_extent(rfs->bmap, 0, 0, 0);
1284         if (retval) goto errout;
1285
1286         if (rfs->progress) {
1287                 retval = (rfs->progress)(rfs, E2_RSZ_BLOCK_RELOC_PASS,
1288                                          0, to_move);
1289                 if (retval)
1290                         goto errout;
1291         }
1292         while (1) {
1293                 retval = ext2fs_iterate_extent(rfs->bmap, &old_blk, &new_blk, &size);
1294                 if (retval) goto errout;
1295                 if (!size)
1296                         break;
1297                 old_blk = C2B(old_blk);
1298                 new_blk = C2B(new_blk);
1299                 size = C2B(size);
1300 #ifdef RESIZE2FS_DEBUG
1301                 if (rfs->flags & RESIZE_DEBUG_BMOVE)
1302                         printf("Moving %llu blocks %llu->%llu\n",
1303                                size, old_blk, new_blk);
1304 #endif
1305                 do {
1306                         c = size;
1307                         if (c > fs->inode_blocks_per_group)
1308                                 c = fs->inode_blocks_per_group;
1309                         retval = io_channel_read_blk64(fs->io, old_blk, c,
1310                                                        rfs->itable_buf);
1311                         if (retval) goto errout;
1312                         retval = io_channel_write_blk64(fs->io, new_blk, c,
1313                                                         rfs->itable_buf);
1314                         if (retval) goto errout;
1315                         size -= c;
1316                         new_blk += c;
1317                         old_blk += c;
1318                         moved += c;
1319                         if (rfs->progress) {
1320                                 io_channel_flush(fs->io);
1321                                 retval = (rfs->progress)(rfs,
1322                                                 E2_RSZ_BLOCK_RELOC_PASS,
1323                                                 moved, to_move);
1324                                 if (retval)
1325                                         goto errout;
1326                         }
1327                 } while (size > 0);
1328                 io_channel_flush(fs->io);
1329         }
1330
1331 errout:
1332         if (badblock_list) {
1333                 if (!retval && bb_modified)
1334                         retval = ext2fs_update_bb_inode(old_fs,
1335                                                         badblock_list);
1336                 ext2fs_badblocks_list_free(badblock_list);
1337         }
1338         return retval;
1339 }
1340
1341
1342 /* --------------------------------------------------------------------
1343  *
1344  * Resize processing, phase 3
1345  *
1346  * --------------------------------------------------------------------
1347  */
1348
1349
1350 /*
1351  * The extent translation table is stored in clusters so we need to
1352  * take special care when mapping a source block number to its
1353  * destination block number.
1354  */
1355 static __u64 extent_translate(ext2_filsys fs, ext2_extent extent, __u64 old_loc)
1356 {
1357         __u64 new_block = C2B(ext2fs_extent_translate(extent, B2C(old_loc)));
1358
1359         if (new_block != 0)
1360                 new_block += old_loc & (EXT2FS_CLUSTER_RATIO(fs) - 1);
1361         return new_block;
1362 }
1363
1364 struct process_block_struct {
1365         ext2_resize_t           rfs;
1366         ext2_ino_t              ino;
1367         struct ext2_inode *     inode;
1368         errcode_t               error;
1369         int                     is_dir;
1370         int                     changed;
1371 };
1372
1373 static int process_block(ext2_filsys fs, blk64_t        *block_nr,
1374                          e2_blkcnt_t blockcnt,
1375                          blk64_t ref_block EXT2FS_ATTR((unused)),
1376                          int ref_offset EXT2FS_ATTR((unused)), void *priv_data)
1377 {
1378         struct process_block_struct *pb;
1379         errcode_t       retval;
1380         blk64_t         block, new_block;
1381         int             ret = 0;
1382
1383         pb = (struct process_block_struct *) priv_data;
1384         block = *block_nr;
1385         if (pb->rfs->bmap) {
1386                 new_block = extent_translate(fs, pb->rfs->bmap, block);
1387                 if (new_block) {
1388                         *block_nr = new_block;
1389                         ret |= BLOCK_CHANGED;
1390                         pb->changed = 1;
1391 #ifdef RESIZE2FS_DEBUG
1392                         if (pb->rfs->flags & RESIZE_DEBUG_BMOVE)
1393                                 printf("ino=%u, blockcnt=%lld, %llu->%llu\n",
1394                                        pb->ino, blockcnt, block, new_block);
1395 #endif
1396                         block = new_block;
1397                 }
1398         }
1399         if (pb->is_dir) {
1400                 retval = ext2fs_add_dir_block2(fs->dblist, pb->ino,
1401                                                block, (int) blockcnt);
1402                 if (retval) {
1403                         pb->error = retval;
1404                         ret |= BLOCK_ABORT;
1405                 }
1406         }
1407         return ret;
1408 }
1409
1410 /*
1411  * Progress callback
1412  */
1413 static errcode_t progress_callback(ext2_filsys fs,
1414                                    ext2_inode_scan scan EXT2FS_ATTR((unused)),
1415                                    dgrp_t group, void * priv_data)
1416 {
1417         ext2_resize_t rfs = (ext2_resize_t) priv_data;
1418         errcode_t               retval;
1419
1420         /*
1421          * This check is to protect against old ext2 libraries.  It
1422          * shouldn't be needed against new libraries.
1423          */
1424         if ((group+1) == 0)
1425                 return 0;
1426
1427         if (rfs->progress) {
1428                 io_channel_flush(fs->io);
1429                 retval = (rfs->progress)(rfs, E2_RSZ_INODE_SCAN_PASS,
1430                                          group+1, fs->group_desc_count);
1431                 if (retval)
1432                         return retval;
1433         }
1434
1435         return 0;
1436 }
1437
1438 static errcode_t inode_scan_and_fix(ext2_resize_t rfs)
1439 {
1440         struct process_block_struct     pb;
1441         ext2_ino_t              ino, new_inode;
1442         struct ext2_inode       *inode = NULL;
1443         ext2_inode_scan         scan = NULL;
1444         errcode_t               retval;
1445         char                    *block_buf = 0;
1446         ext2_ino_t              start_to_move;
1447         blk64_t                 orig_size;
1448         blk64_t                 new_block;
1449         int                     inode_size;
1450
1451         if ((rfs->old_fs->group_desc_count <=
1452              rfs->new_fs->group_desc_count) &&
1453             !rfs->bmap)
1454                 return 0;
1455
1456         /*
1457          * Save the original size of the old filesystem, and
1458          * temporarily set the size to be the new size if the new size
1459          * is larger.  We need to do this to avoid catching an error
1460          * by the block iterator routines
1461          */
1462         orig_size = ext2fs_blocks_count(rfs->old_fs->super);
1463         if (orig_size < ext2fs_blocks_count(rfs->new_fs->super))
1464                 ext2fs_blocks_count_set(rfs->old_fs->super,
1465                                 ext2fs_blocks_count(rfs->new_fs->super));
1466
1467         retval = ext2fs_open_inode_scan(rfs->old_fs, 0, &scan);
1468         if (retval) goto errout;
1469
1470         retval = ext2fs_init_dblist(rfs->old_fs, 0);
1471         if (retval) goto errout;
1472         retval = ext2fs_get_array(rfs->old_fs->blocksize, 3, &block_buf);
1473         if (retval) goto errout;
1474
1475         start_to_move = (rfs->new_fs->group_desc_count *
1476                          rfs->new_fs->super->s_inodes_per_group);
1477
1478         if (rfs->progress) {
1479                 retval = (rfs->progress)(rfs, E2_RSZ_INODE_SCAN_PASS,
1480                                          0, rfs->old_fs->group_desc_count);
1481                 if (retval)
1482                         goto errout;
1483         }
1484         ext2fs_set_inode_callback(scan, progress_callback, (void *) rfs);
1485         pb.rfs = rfs;
1486         pb.inode = inode;
1487         pb.error = 0;
1488         new_inode = EXT2_FIRST_INODE(rfs->new_fs->super);
1489         inode_size = EXT2_INODE_SIZE(rfs->new_fs->super);
1490         inode = malloc(inode_size);
1491         if (!inode) {
1492                 retval = ENOMEM;
1493                 goto errout;
1494         }
1495         /*
1496          * First, copy all of the inodes that need to be moved
1497          * elsewhere in the inode table
1498          */
1499         while (1) {
1500                 retval = ext2fs_get_next_inode_full(scan, &ino, inode, inode_size);
1501                 if (retval) goto errout;
1502                 if (!ino)
1503                         break;
1504
1505                 if (inode->i_links_count == 0 && ino != EXT2_RESIZE_INO)
1506                         continue; /* inode not in use */
1507
1508                 pb.is_dir = LINUX_S_ISDIR(inode->i_mode);
1509                 pb.changed = 0;
1510
1511                 if (ext2fs_file_acl_block(rfs->old_fs, inode) && rfs->bmap) {
1512                         new_block = extent_translate(rfs->old_fs, rfs->bmap,
1513                                 ext2fs_file_acl_block(rfs->old_fs, inode));
1514                         if (new_block) {
1515                                 ext2fs_file_acl_block_set(rfs->old_fs, inode,
1516                                                           new_block);
1517                                 retval = ext2fs_write_inode_full(rfs->old_fs,
1518                                                             ino, inode, inode_size);
1519                                 if (retval) goto errout;
1520                         }
1521                 }
1522
1523                 if (ext2fs_inode_has_valid_blocks2(rfs->old_fs, inode) &&
1524                     (rfs->bmap || pb.is_dir)) {
1525                         pb.ino = ino;
1526                         retval = ext2fs_block_iterate3(rfs->old_fs,
1527                                                        ino, 0, block_buf,
1528                                                        process_block, &pb);
1529                         if (retval)
1530                                 goto errout;
1531                         if (pb.error) {
1532                                 retval = pb.error;
1533                                 goto errout;
1534                         }
1535                 }
1536
1537                 if (ino <= start_to_move)
1538                         continue; /* Don't need to move it. */
1539
1540                 /*
1541                  * Find a new inode
1542                  */
1543                 retval = ext2fs_new_inode(rfs->new_fs, 0, 0, 0, &new_inode);
1544                 if (retval)
1545                         goto errout;
1546
1547                 ext2fs_inode_alloc_stats2(rfs->new_fs, new_inode, +1,
1548                                           pb.is_dir);
1549                 if (pb.changed) {
1550                         /* Get the new version of the inode */
1551                         retval = ext2fs_read_inode_full(rfs->old_fs, ino,
1552                                                 inode, inode_size);
1553                         if (retval) goto errout;
1554                 }
1555                 inode->i_ctime = time(0);
1556                 retval = ext2fs_write_inode_full(rfs->old_fs, new_inode,
1557                                                 inode, inode_size);
1558                 if (retval) goto errout;
1559
1560 #ifdef RESIZE2FS_DEBUG
1561                 if (rfs->flags & RESIZE_DEBUG_INODEMAP)
1562                         printf("Inode moved %u->%u\n", ino, new_inode);
1563 #endif
1564                 if (!rfs->imap) {
1565                         retval = ext2fs_create_extent_table(&rfs->imap, 0);
1566                         if (retval)
1567                                 goto errout;
1568                 }
1569                 ext2fs_add_extent_entry(rfs->imap, ino, new_inode);
1570         }
1571         io_channel_flush(rfs->old_fs->io);
1572
1573 errout:
1574         ext2fs_blocks_count_set(rfs->old_fs->super, orig_size);
1575         if (rfs->bmap) {
1576                 ext2fs_free_extent_table(rfs->bmap);
1577                 rfs->bmap = 0;
1578         }
1579         if (scan)
1580                 ext2fs_close_inode_scan(scan);
1581         if (block_buf)
1582                 ext2fs_free_mem(&block_buf);
1583         free(inode);
1584         return retval;
1585 }
1586
1587 /* --------------------------------------------------------------------
1588  *
1589  * Resize processing, phase 4.
1590  *
1591  * --------------------------------------------------------------------
1592  */
1593
1594 struct istruct {
1595         ext2_resize_t rfs;
1596         errcode_t       err;
1597         unsigned int    max_dirs;
1598         unsigned int    num;
1599 };
1600
1601 static int check_and_change_inodes(ext2_ino_t dir,
1602                                    int entry EXT2FS_ATTR((unused)),
1603                                    struct ext2_dir_entry *dirent, int offset,
1604                                    int  blocksize EXT2FS_ATTR((unused)),
1605                                    char *buf EXT2FS_ATTR((unused)),
1606                                    void *priv_data)
1607 {
1608         struct istruct *is = (struct istruct *) priv_data;
1609         struct ext2_inode       inode;
1610         ext2_ino_t              new_inode;
1611         errcode_t               retval;
1612
1613         if (is->rfs->progress && offset == 0) {
1614                 io_channel_flush(is->rfs->old_fs->io);
1615                 is->err = (is->rfs->progress)(is->rfs,
1616                                               E2_RSZ_INODE_REF_UPD_PASS,
1617                                               ++is->num, is->max_dirs);
1618                 if (is->err)
1619                         return DIRENT_ABORT;
1620         }
1621
1622         if (!dirent->inode)
1623                 return 0;
1624
1625         new_inode = ext2fs_extent_translate(is->rfs->imap, dirent->inode);
1626
1627         if (!new_inode)
1628                 return 0;
1629 #ifdef RESIZE2FS_DEBUG
1630         if (is->rfs->flags & RESIZE_DEBUG_INODEMAP)
1631                 printf("Inode translate (dir=%u, name=%.*s, %u->%u)\n",
1632                        dir, dirent->name_len&0xFF, dirent->name,
1633                        dirent->inode, new_inode);
1634 #endif
1635
1636         dirent->inode = new_inode;
1637
1638         /* Update the directory mtime and ctime */
1639         retval = ext2fs_read_inode(is->rfs->old_fs, dir, &inode);
1640         if (retval == 0) {
1641                 inode.i_mtime = inode.i_ctime = time(0);
1642                 is->err = ext2fs_write_inode(is->rfs->old_fs, dir, &inode);
1643                 if (is->err)
1644                         return DIRENT_ABORT;
1645         }
1646
1647         return DIRENT_CHANGED;
1648 }
1649
1650 static errcode_t inode_ref_fix(ext2_resize_t rfs)
1651 {
1652         errcode_t               retval;
1653         struct istruct          is;
1654
1655         if (!rfs->imap)
1656                 return 0;
1657
1658         /*
1659          * Now, we iterate over all of the directories to update the
1660          * inode references
1661          */
1662         is.num = 0;
1663         is.max_dirs = ext2fs_dblist_count2(rfs->old_fs->dblist);
1664         is.rfs = rfs;
1665         is.err = 0;
1666
1667         if (rfs->progress) {
1668                 retval = (rfs->progress)(rfs, E2_RSZ_INODE_REF_UPD_PASS,
1669                                          0, is.max_dirs);
1670                 if (retval)
1671                         goto errout;
1672         }
1673
1674         retval = ext2fs_dblist_dir_iterate(rfs->old_fs->dblist,
1675                                            DIRENT_FLAG_INCLUDE_EMPTY, 0,
1676                                            check_and_change_inodes, &is);
1677         if (retval)
1678                 goto errout;
1679         if (is.err) {
1680                 retval = is.err;
1681                 goto errout;
1682         }
1683
1684         if (rfs->progress && (is.num < is.max_dirs))
1685                 (rfs->progress)(rfs, E2_RSZ_INODE_REF_UPD_PASS,
1686                                 is.max_dirs, is.max_dirs);
1687
1688 errout:
1689         ext2fs_free_extent_table(rfs->imap);
1690         rfs->imap = 0;
1691         return retval;
1692 }
1693
1694
1695 /* --------------------------------------------------------------------
1696  *
1697  * Resize processing, phase 5.
1698  *
1699  * In this phase we actually move the inode table around, and then
1700  * update the summary statistics.  This is scary, since aborting here
1701  * will potentially scramble the filesystem.  (We are moving the
1702  * inode tables around in place, and so the potential for lost data,
1703  * or at the very least scrambling the mapping between filenames and
1704  * inode numbers is very high in case of a power failure here.)
1705  * --------------------------------------------------------------------
1706  */
1707
1708
1709 /*
1710  * A very scary routine --- this one moves the inode table around!!!
1711  *
1712  * After this you have to use the rfs->new_fs file handle to read and
1713  * write inodes.
1714  */
1715 static errcode_t move_itables(ext2_resize_t rfs)
1716 {
1717         int             n, num, size;
1718         long long       diff;
1719         dgrp_t          i, max_groups;
1720         ext2_filsys     fs = rfs->new_fs;
1721         char            *cp;
1722         blk64_t         old_blk, new_blk, blk;
1723         errcode_t       retval;
1724         int             j, to_move, moved;
1725
1726         max_groups = fs->group_desc_count;
1727         if (max_groups > rfs->old_fs->group_desc_count)
1728                 max_groups = rfs->old_fs->group_desc_count;
1729
1730         size = fs->blocksize * fs->inode_blocks_per_group;
1731         if (!rfs->itable_buf) {
1732                 retval = ext2fs_get_mem(size, &rfs->itable_buf);
1733                 if (retval)
1734                         return retval;
1735         }
1736
1737         /*
1738          * Figure out how many inode tables we need to move
1739          */
1740         to_move = moved = 0;
1741         for (i=0; i < max_groups; i++)
1742                 if (ext2fs_inode_table_loc(rfs->old_fs, i) !=
1743                     ext2fs_inode_table_loc(fs, i))
1744                         to_move++;
1745
1746         if (to_move == 0)
1747                 return 0;
1748
1749         if (rfs->progress) {
1750                 retval = rfs->progress(rfs, E2_RSZ_MOVE_ITABLE_PASS,
1751                                        0, to_move);
1752                 if (retval)
1753                         goto errout;
1754         }
1755
1756         rfs->old_fs->flags |= EXT2_FLAG_MASTER_SB_ONLY;
1757
1758         for (i=0; i < max_groups; i++) {
1759                 old_blk = ext2fs_inode_table_loc(rfs->old_fs, i);
1760                 new_blk = ext2fs_inode_table_loc(fs, i);
1761                 diff = new_blk - old_blk;
1762
1763 #ifdef RESIZE2FS_DEBUG
1764                 if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
1765                         printf("Itable move group %d block %llu->%llu (diff %lld)\n",
1766                                i, old_blk, new_blk, diff);
1767 #endif
1768
1769                 if (!diff)
1770                         continue;
1771
1772                 retval = io_channel_read_blk64(fs->io, old_blk,
1773                                                fs->inode_blocks_per_group,
1774                                                rfs->itable_buf);
1775                 if (retval)
1776                         goto errout;
1777                 /*
1778                  * The end of the inode table segment often contains
1779                  * all zeros, and we're often only moving the inode
1780                  * table down a block or two.  If so, we can optimize
1781                  * things by not rewriting blocks that we know to be zero
1782                  * already.
1783                  */
1784                 for (cp = rfs->itable_buf+size-1, n=0; n < size; n++, cp--)
1785                         if (*cp)
1786                                 break;
1787                 n = n >> EXT2_BLOCK_SIZE_BITS(fs->super);
1788 #ifdef RESIZE2FS_DEBUG
1789                 if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
1790                         printf("%d blocks of zeros...\n", n);
1791 #endif
1792                 num = fs->inode_blocks_per_group;
1793                 if (n > diff)
1794                         num -= n;
1795
1796                 retval = io_channel_write_blk64(fs->io, new_blk,
1797                                                 num, rfs->itable_buf);
1798                 if (retval) {
1799                         io_channel_write_blk64(fs->io, old_blk,
1800                                                num, rfs->itable_buf);
1801                         goto errout;
1802                 }
1803                 if (n > diff) {
1804                         retval = io_channel_write_blk64(fs->io,
1805                               old_blk + fs->inode_blocks_per_group,
1806                               diff, (rfs->itable_buf +
1807                                      (fs->inode_blocks_per_group - diff) *
1808                                      fs->blocksize));
1809                         if (retval)
1810                                 goto errout;
1811                 }
1812
1813                 for (blk = ext2fs_inode_table_loc(rfs->old_fs, i), j=0;
1814                      j < fs->inode_blocks_per_group ; j++, blk++)
1815                         ext2fs_block_alloc_stats2(fs, blk, -1);
1816
1817                 ext2fs_inode_table_loc_set(rfs->old_fs, i, new_blk);
1818                 ext2fs_group_desc_csum_set(rfs->old_fs, i);
1819                 ext2fs_mark_super_dirty(rfs->old_fs);
1820                 ext2fs_flush(rfs->old_fs);
1821
1822                 if (rfs->progress) {
1823                         retval = rfs->progress(rfs, E2_RSZ_MOVE_ITABLE_PASS,
1824                                                ++moved, to_move);
1825                         if (retval)
1826                                 goto errout;
1827                 }
1828         }
1829         mark_table_blocks(fs, fs->block_map);
1830         ext2fs_flush(fs);
1831 #ifdef RESIZE2FS_DEBUG
1832         if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
1833                 printf("Inode table move finished.\n");
1834 #endif
1835         return 0;
1836
1837 errout:
1838         return retval;
1839 }
1840
1841 /*
1842  * Fix the resize inode
1843  */
1844 static errcode_t fix_resize_inode(ext2_filsys fs)
1845 {
1846         struct ext2_inode       inode;
1847         errcode_t               retval;
1848         char                    *block_buf = NULL;
1849
1850         if (!(fs->super->s_feature_compat &
1851               EXT2_FEATURE_COMPAT_RESIZE_INODE))
1852                 return 0;
1853
1854         retval = ext2fs_get_mem(fs->blocksize, &block_buf);
1855         if (retval) goto errout;
1856
1857         retval = ext2fs_read_inode(fs, EXT2_RESIZE_INO, &inode);
1858         if (retval) goto errout;
1859
1860         ext2fs_iblk_set(fs, &inode, 1);
1861
1862         retval = ext2fs_write_inode(fs, EXT2_RESIZE_INO, &inode);
1863         if (retval) goto errout;
1864
1865         if (!inode.i_block[EXT2_DIND_BLOCK]) {
1866                 /*
1867                  * Avoid zeroing out block #0; that's rude.  This
1868                  * should never happen anyway since the filesystem
1869                  * should be fsck'ed and we assume it is consistent.
1870                  */
1871                 fprintf(stderr, "%s",
1872                         _("Should never happen: resize inode corrupt!\n"));
1873                 exit(1);
1874         }
1875
1876         memset(block_buf, 0, fs->blocksize);
1877
1878         retval = io_channel_write_blk64(fs->io, inode.i_block[EXT2_DIND_BLOCK],
1879                                         1, block_buf);
1880         if (retval) goto errout;
1881
1882         retval = ext2fs_create_resize_inode(fs);
1883         if (retval)
1884                 goto errout;
1885
1886 errout:
1887         if (block_buf)
1888                 ext2fs_free_mem(&block_buf);
1889         return retval;
1890 }
1891
1892 /*
1893  * Finally, recalculate the summary information
1894  */
1895 static errcode_t ext2fs_calculate_summary_stats(ext2_filsys fs)
1896 {
1897         blk64_t         blk;
1898         ext2_ino_t      ino;
1899         unsigned int    group = 0;
1900         unsigned int    count = 0;
1901         blk64_t         total_blocks_free = 0;
1902         int             total_inodes_free = 0;
1903         int             group_free = 0;
1904         int             uninit = 0;
1905         blk64_t         super_blk, old_desc_blk, new_desc_blk;
1906         int             old_desc_blocks;
1907
1908         /*
1909          * First calculate the block statistics
1910          */
1911         uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_BLOCK_UNINIT);
1912         ext2fs_super_and_bgd_loc2(fs, group, &super_blk, &old_desc_blk,
1913                                   &new_desc_blk, 0);
1914         if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
1915                 old_desc_blocks = fs->super->s_first_meta_bg;
1916         else
1917                 old_desc_blocks = fs->desc_blocks +
1918                         fs->super->s_reserved_gdt_blocks;
1919         for (blk = B2C(fs->super->s_first_data_block);
1920              blk < ext2fs_blocks_count(fs->super);
1921              blk += EXT2FS_CLUSTER_RATIO(fs)) {
1922                 if ((uninit &&
1923                      !(EQ_CLSTR(blk, super_blk) ||
1924                        ((old_desc_blk && old_desc_blocks &&
1925                          GE_CLSTR(blk, old_desc_blk) &&
1926                          LT_CLSTR(blk, old_desc_blk + old_desc_blocks))) ||
1927                        ((new_desc_blk && EQ_CLSTR(blk, new_desc_blk))) ||
1928                        EQ_CLSTR(blk, ext2fs_block_bitmap_loc(fs, group)) ||
1929                        EQ_CLSTR(blk, ext2fs_inode_bitmap_loc(fs, group)) ||
1930                        ((GE_CLSTR(blk, ext2fs_inode_table_loc(fs, group)) &&
1931                          LT_CLSTR(blk, ext2fs_inode_table_loc(fs, group)
1932                                   + fs->inode_blocks_per_group))))) ||
1933                     (!ext2fs_fast_test_block_bitmap2(fs->block_map, blk))) {
1934                         group_free++;
1935                         total_blocks_free++;
1936                 }
1937                 count++;
1938                 if ((count == fs->super->s_clusters_per_group) ||
1939                     EQ_CLSTR(blk, ext2fs_blocks_count(fs->super)-1)) {
1940                         ext2fs_bg_free_blocks_count_set(fs, group, group_free);
1941                         ext2fs_group_desc_csum_set(fs, group);
1942                         group++;
1943                         if (group >= fs->group_desc_count)
1944                                 break;
1945                         count = 0;
1946                         group_free = 0;
1947                         uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_BLOCK_UNINIT);
1948                         ext2fs_super_and_bgd_loc2(fs, group, &super_blk,
1949                                                   &old_desc_blk,
1950                                                   &new_desc_blk, 0);
1951                         if (fs->super->s_feature_incompat &
1952                             EXT2_FEATURE_INCOMPAT_META_BG)
1953                                 old_desc_blocks = fs->super->s_first_meta_bg;
1954                         else
1955                                 old_desc_blocks = fs->desc_blocks +
1956                                         fs->super->s_reserved_gdt_blocks;
1957                 }
1958         }
1959         total_blocks_free = C2B(total_blocks_free);
1960         ext2fs_free_blocks_count_set(fs->super, total_blocks_free);
1961
1962         /*
1963          * Next, calculate the inode statistics
1964          */
1965         group_free = 0;
1966         count = 0;
1967         group = 0;
1968
1969         /* Protect loop from wrap-around if s_inodes_count maxed */
1970         uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_INODE_UNINIT);
1971         for (ino = 1; ino <= fs->super->s_inodes_count && ino > 0; ino++) {
1972                 if (uninit ||
1973                     !ext2fs_fast_test_inode_bitmap2(fs->inode_map, ino)) {
1974                         group_free++;
1975                         total_inodes_free++;
1976                 }
1977                 count++;
1978                 if ((count == fs->super->s_inodes_per_group) ||
1979                     (ino == fs->super->s_inodes_count)) {
1980                         ext2fs_bg_free_inodes_count_set(fs, group, group_free);
1981                         ext2fs_group_desc_csum_set(fs, group);
1982                         group++;
1983                         if (group >= fs->group_desc_count)
1984                                 break;
1985                         count = 0;
1986                         group_free = 0;
1987                         uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_INODE_UNINIT);
1988                 }
1989         }
1990         fs->super->s_free_inodes_count = total_inodes_free;
1991         ext2fs_mark_super_dirty(fs);
1992         return 0;
1993 }
1994
1995 /*
1996  *  Journal may have been relocated; update the backup journal blocks
1997  *  in the superblock.
1998  */
1999 static errcode_t fix_sb_journal_backup(ext2_filsys fs)
2000 {
2001         errcode_t         retval;
2002         struct ext2_inode inode;
2003
2004         if (!(fs->super->s_feature_compat & EXT3_FEATURE_COMPAT_HAS_JOURNAL))
2005                 return 0;
2006
2007         /* External journal? Nothing to do. */
2008         if (fs->super->s_journal_dev && !fs->super->s_journal_inum)
2009                 return 0;
2010
2011         retval = ext2fs_read_inode(fs, fs->super->s_journal_inum, &inode);
2012         if (retval)
2013                 return retval;
2014         memcpy(fs->super->s_jnl_blocks, inode.i_block, EXT2_N_BLOCKS*4);
2015         fs->super->s_jnl_blocks[15] = inode.i_size_high;
2016         fs->super->s_jnl_blocks[16] = inode.i_size;
2017         fs->super->s_jnl_backup_type = EXT3_JNL_BACKUP_BLOCKS;
2018         ext2fs_mark_super_dirty(fs);
2019         return 0;
2020 }
2021
2022 static int calc_group_overhead(ext2_filsys fs, blk64_t grp,
2023                                int old_desc_blocks)
2024 {
2025         blk64_t super_blk, old_desc_blk, new_desc_blk;
2026         int overhead;
2027
2028         /* inode table blocks plus allocation bitmaps */
2029         overhead = fs->inode_blocks_per_group + 2;
2030
2031         ext2fs_super_and_bgd_loc2(fs, grp, &super_blk,
2032                                   &old_desc_blk, &new_desc_blk, 0);
2033         if ((grp == 0) || super_blk)
2034                 overhead++;
2035         if (old_desc_blk)
2036                 overhead += old_desc_blocks;
2037         else if (new_desc_blk)
2038                 overhead++;
2039         return overhead;
2040 }
2041
2042
2043 /*
2044  * calcluate the minimum number of blocks the given fs can be resized to
2045  */
2046 blk64_t calculate_minimum_resize_size(ext2_filsys fs, int flags)
2047 {
2048         ext2_ino_t inode_count;
2049         dgrp_t groups;
2050         blk64_t blks_needed, data_blocks;
2051         blk64_t grp, data_needed, last_start;
2052         blk64_t overhead = 0;
2053         int old_desc_blocks;
2054         int extra_groups = 0;
2055         int flexbg_size = 1 << fs->super->s_log_groups_per_flex;
2056
2057         /*
2058          * first figure out how many group descriptors we need to
2059          * handle the number of inodes we have
2060          */
2061         inode_count = fs->super->s_inodes_count -
2062                 fs->super->s_free_inodes_count;
2063         blks_needed = ext2fs_div_ceil(inode_count,
2064                                       fs->super->s_inodes_per_group) *
2065                 EXT2_BLOCKS_PER_GROUP(fs->super);
2066         groups = ext2fs_div64_ceil(blks_needed,
2067                                    EXT2_BLOCKS_PER_GROUP(fs->super));
2068 #ifdef RESIZE2FS_DEBUG
2069         if (flags & RESIZE_DEBUG_MIN_CALC)
2070                 printf("fs has %d inodes, %d groups required.\n",
2071                        inode_count, groups);
2072 #endif
2073
2074         /*
2075          * number of old-style block group descriptor blocks
2076          */
2077         if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
2078                 old_desc_blocks = fs->super->s_first_meta_bg;
2079         else
2080                 old_desc_blocks = fs->desc_blocks +
2081                         fs->super->s_reserved_gdt_blocks;
2082
2083         /* calculate how many blocks are needed for data */
2084         data_needed = ext2fs_blocks_count(fs->super) -
2085                 ext2fs_free_blocks_count(fs->super);
2086
2087         for (grp = 0; grp < fs->group_desc_count; grp++)
2088                 data_needed -= calc_group_overhead(fs, grp, old_desc_blocks);
2089 #ifdef RESIZE2FS_DEBUG
2090         if (flags & RESIZE_DEBUG_MIN_CALC)
2091                 printf("fs requires %llu data blocks.\n", data_needed);
2092 #endif
2093
2094         /*
2095          * For ext4 we need to allow for up to a flex_bg worth of
2096          * inode tables of slack space so the resize operation can be
2097          * guaranteed to finish.
2098          */
2099         if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_FLEX_BG) {
2100                 extra_groups = flexbg_size - (groups & (flexbg_size - 1));
2101                 data_needed += fs->inode_blocks_per_group * extra_groups;
2102                 extra_groups = groups % flexbg_size;
2103         }
2104
2105         /*
2106          * figure out how many data blocks we have given the number of groups
2107          * we need for our inodes
2108          */
2109         data_blocks = groups * EXT2_BLOCKS_PER_GROUP(fs->super);
2110         last_start = 0;
2111         for (grp = 0; grp < groups; grp++) {
2112                 overhead = calc_group_overhead(fs, grp, old_desc_blocks);
2113
2114                 /*
2115                  * we want to keep track of how much data we can store in
2116                  * the groups leading up to the last group so we can determine
2117                  * how big the last group needs to be
2118                  */
2119                 if (grp != (groups - 1))
2120                         last_start += EXT2_BLOCKS_PER_GROUP(fs->super) -
2121                                 overhead;
2122
2123                 data_blocks -= overhead;
2124         }
2125 #ifdef RESIZE2FS_DEBUG
2126         if (flags & RESIZE_DEBUG_MIN_CALC)
2127                 printf("With %d group(s), we have %llu blocks available.\n",
2128                        groups, data_blocks);
2129 #endif
2130
2131         /*
2132          * if we need more group descriptors in order to accomodate our data
2133          * then we need to add them here
2134          */
2135         while (data_needed > data_blocks) {
2136                 blk64_t remainder = data_needed - data_blocks;
2137                 dgrp_t extra_grps;
2138
2139                 /* figure out how many more groups we need for the data */
2140                 extra_grps = ext2fs_div64_ceil(remainder,
2141                                                EXT2_BLOCKS_PER_GROUP(fs->super));
2142
2143                 data_blocks += extra_grps * EXT2_BLOCKS_PER_GROUP(fs->super);
2144
2145                 /* ok we have to account for the last group */
2146                 overhead = calc_group_overhead(fs, groups-1, old_desc_blocks);
2147                 last_start += EXT2_BLOCKS_PER_GROUP(fs->super) - overhead;
2148
2149                 for (grp = groups; grp < groups+extra_grps; grp++) {
2150                         overhead = calc_group_overhead(fs, grp,
2151                                                        old_desc_blocks);
2152
2153                         /*
2154                          * again, we need to see how much data we cram into
2155                          * all of the groups leading up to the last group
2156                          */
2157                         if (grp != (groups + extra_grps - 1))
2158                                 last_start += EXT2_BLOCKS_PER_GROUP(fs->super)
2159                                         - overhead;
2160
2161                         data_blocks -= overhead;
2162                 }
2163
2164                 groups += extra_grps;
2165                 extra_groups += extra_grps;
2166                 if (fs->super->s_feature_incompat
2167                         & EXT4_FEATURE_INCOMPAT_FLEX_BG
2168                     && extra_groups > flexbg_size) {
2169                         /*
2170                          * For ext4 we need to allow for up to a flex_bg worth
2171                          * of inode tables of slack space so the resize
2172                          * operation can be guaranteed to finish.
2173                          */
2174                         extra_groups = flexbg_size -
2175                                                 (groups & (flexbg_size - 1));
2176                         data_needed += (fs->inode_blocks_per_group *
2177                                         extra_groups);
2178                         extra_groups = groups % flexbg_size;
2179                 }
2180 #ifdef RESIZE2FS_DEBUG
2181                 if (flags & RESIZE_DEBUG_MIN_CALC)
2182                         printf("Added %d extra group(s), "
2183                                "data_needed %llu, data_blocks %llu, "
2184                                "last_start %llu\n",
2185                                extra_grps, data_needed, data_blocks,
2186                                last_start);
2187 #endif
2188         }
2189
2190         /* now for the fun voodoo */
2191         overhead = calc_group_overhead(fs, groups-1, old_desc_blocks);
2192 #ifdef RESIZE2FS_DEBUG
2193         if (flags & RESIZE_DEBUG_MIN_CALC)
2194                 printf("Last group's overhead is %llu\n", overhead);
2195 #endif
2196
2197         /*
2198          * if this is the case then the last group is going to have data in it
2199          * so we need to adjust the size of the last group accordingly
2200          */
2201         if (last_start < data_needed) {
2202                 blk64_t remainder = data_needed - last_start;
2203
2204 #ifdef RESIZE2FS_DEBUG
2205                 if (flags & RESIZE_DEBUG_MIN_CALC)
2206                         printf("Need %llu data blocks in last group\n",
2207                                remainder);
2208 #endif
2209                 /*
2210                  * 50 is a magic number that mkfs/resize uses to see if its
2211                  * even worth making/resizing the fs.  basically you need to
2212                  * have at least 50 blocks in addition to the blocks needed
2213                  * for the metadata in the last group
2214                  */
2215                 if (remainder > 50)
2216                         overhead += remainder;
2217                 else
2218                         overhead += 50;
2219         } else
2220                 overhead += 50;
2221
2222         overhead += fs->super->s_first_data_block;
2223 #ifdef RESIZE2FS_DEBUG
2224         if (flags & RESIZE_DEBUG_MIN_CALC)
2225                 printf("Final size of last group is %lld\n", overhead);
2226 #endif
2227
2228         /*
2229          * since our last group doesn't have to be BLOCKS_PER_GROUP large, we
2230          * only do groups-1, and then add the number of blocks needed to
2231          * handle the group descriptor metadata+data that we need
2232          */
2233         blks_needed = (groups-1) * EXT2_BLOCKS_PER_GROUP(fs->super);
2234         blks_needed += overhead;
2235
2236         /*
2237          * Make sure blks_needed covers the end of the inode table in
2238          * the last block group.
2239          */
2240         overhead = ext2fs_inode_table_loc(fs, groups-1) +
2241                 fs->inode_blocks_per_group;
2242         if (blks_needed < overhead)
2243                 blks_needed = overhead;
2244
2245 #ifdef RESIZE2FS_DEBUG
2246         if (flags & RESIZE_DEBUG_MIN_CALC)
2247                 printf("Estimated blocks needed: %llu\n", blks_needed);
2248 #endif
2249
2250         /*
2251          * If at this point we've already added up more "needed" than
2252          * the current size, just return current size as minimum.
2253          */
2254         if (blks_needed >= ext2fs_blocks_count(fs->super))
2255                 return ext2fs_blocks_count(fs->super);
2256         /*
2257          * We need to reserve a few extra blocks if extents are
2258          * enabled, in case we need to grow the extent tree.  The more
2259          * we shrink the file system, the more space we need.
2260          */
2261         if (fs->super->s_feature_incompat & EXT3_FEATURE_INCOMPAT_EXTENTS) {
2262                 blk64_t safe_margin = (ext2fs_blocks_count(fs->super) -
2263                                        blks_needed)/500;
2264 #ifdef RESIZE2FS_DEBUG
2265                 if (flags & RESIZE_DEBUG_MIN_CALC)
2266                         printf("Extents safety margin: %llu\n", safe_margin);
2267 #endif
2268                 blks_needed += safe_margin;
2269         }
2270
2271         return blks_needed;
2272 }