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 errcode_t adjust_superblock(ext2_resize_t rfs, blk_t new_size);
  44 static errcode_t blocks_to_move(ext2_resize_t rfs);
  45 static errcode_t block_mover(ext2_resize_t rfs);
  46 static errcode_t inode_scan_and_fix(ext2_resize_t rfs);
  47 static errcode_t inode_ref_fix(ext2_resize_t rfs);
  48 static errcode_t move_itables(ext2_resize_t rfs);
  49 static errcode_t fix_resize_inode(ext2_filsys fs);
  50 static errcode_t ext2fs_calculate_summary_stats(ext2_filsys fs);
  51
  52 /*
  53  * Some helper CPP macros
  54  */
  55 #define FS_BLOCK_BM(fs, i) ((fs)->group_desc[(i)].bg_block_bitmap)
  56 #define FS_INODE_BM(fs, i) ((fs)->group_desc[(i)].bg_inode_bitmap)
  57 #define FS_INODE_TB(fs, i) ((fs)->group_desc[(i)].bg_inode_table)
  58
  59 #define IS_BLOCK_BM(fs, i, blk) ((blk) == FS_BLOCK_BM((fs),(i)))
  60 #define IS_INODE_BM(fs, i, blk) ((blk) == FS_INODE_BM((fs),(i)))
  61
  62 #define IS_INODE_TB(fs, i, blk) (((blk) >= FS_INODE_TB((fs), (i))) && \
  63                                  ((blk) < (FS_INODE_TB((fs), (i)) + \
  64                                            (fs)->inode_blocks_per_group)))
  65
  66
  67
  68 /*
  69  * This is the top-level routine which does the dirty deed....
  70  */
  71 errcode_t resize_fs(ext2_filsys fs, blk_t *new_size, int flags,
  72                     errcode_t (*progress)(ext2_resize_t rfs, int pass,
  73                                      unsigned long cur,
  74                                      unsigned long max_val))
  75 {
  76         ext2_resize_t   rfs;
  77         errcode_t       retval;
  78
  79         retval = ext2fs_read_bitmaps(fs);
  80         if (retval)
  81                 return retval;
  82
  83         /*
  84          * Create the data structure
  85          */
  86         retval = ext2fs_get_mem(sizeof(struct ext2_resize_struct), &rfs);
  87         if (retval)
  88                 return retval;
  89         memset(rfs, 0, sizeof(struct ext2_resize_struct));
  90
  91         rfs->old_fs = fs;
  92         rfs->flags = flags;
  93         rfs->itable_buf  = 0;
  94         rfs->progress = progress;
  95         retval = ext2fs_dup_handle(fs, &rfs->new_fs);
  96         if (retval)
  97                 goto errout;
  98
  99         retval = adjust_superblock(rfs, *new_size);
 100         if (retval)
 101                 goto errout;
 102
 103         *new_size = rfs->new_fs->super->s_blocks_count;
 104
 105         retval = blocks_to_move(rfs);
 106         if (retval)
 107                 goto errout;
 108
 109 #ifdef RESIZE2FS_DEBUG
 110         if (rfs->flags & RESIZE_DEBUG_BMOVE)
 111                 printf("Number of free blocks: %u/%u, Needed: %d\n",
 112                        rfs->old_fs->super->s_free_blocks_count,
 113                        rfs->new_fs->super->s_free_blocks_count,
 114                        rfs->needed_blocks);
 115 #endif
 116
 117         retval = block_mover(rfs);
 118         if (retval)
 119                 goto errout;
 120
 121         retval = inode_scan_and_fix(rfs);
 122         if (retval)
 123                 goto errout;
 124
 125         retval = inode_ref_fix(rfs);
 126         if (retval)
 127                 goto errout;
 128
 129         retval = move_itables(rfs);
 130         if (retval)
 131                 goto errout;
 132
 133         retval = ext2fs_calculate_summary_stats(rfs->new_fs);
 134         if (retval)
 135                 goto errout;
 136
 137         retval = fix_resize_inode(rfs->new_fs);
 138         if (retval)
 139                 goto errout;
 140
 141         retval = ext2fs_close(rfs->new_fs);
 142         if (retval)
 143                 goto errout;
 144
 145         rfs->flags = flags;
 146
 147         ext2fs_free(rfs->old_fs);
 148         if (rfs->itable_buf)
 149                 ext2fs_free_mem(&rfs->itable_buf);
 150         ext2fs_free_mem(&rfs);
 151
 152         return 0;
 153
 154 errout:
 155         if (rfs->new_fs)
 156                 ext2fs_free(rfs->new_fs);
 157         if (rfs->itable_buf)
 158                 ext2fs_free_mem(&rfs->itable_buf);
 159         ext2fs_free_mem(&rfs);
 160         return retval;
 161 }
 162
 163 /* --------------------------------------------------------------------
 164  *
 165  * Resize processing, phase 1.
 166  *
 167  * In this phase we adjust the in-memory superblock information, and
 168  * initialize any new parts of the inode table.  The new parts of the
 169  * inode table are created in virgin disk space, so we can abort here
 170  * without any side effects.
 171  * --------------------------------------------------------------------
 172  */
 173
 174 /*
 175  * This routine is shared by the online and offline resize routines.
 176  * All of the information which is adjusted in memory is done here.
 177  */
 178 errcode_t adjust_fs_info(ext2_filsys fs, ext2_filsys old_fs, blk_t new_size)
 179 {
 180         errcode_t       retval;
 181         int             overhead = 0;
 182         int             rem;
 183         blk_t           blk, group_block;
 184         ext2_ino_t      real_end;
 185         int             adj, old_numblocks, numblocks, adjblocks;
 186         unsigned long   i, j, old_desc_blocks, max_group;
 187         unsigned int    meta_bg, meta_bg_size;
 188         int             has_super;
 189         __u64           new_inodes;     /* u64 to check for overflow */
 190
 191         fs->super->s_blocks_count = new_size;
 192
 193 retry:
 194         fs->group_desc_count = ext2fs_div_ceil(fs->super->s_blocks_count -
 195                                        fs->super->s_first_data_block,
 196                                        EXT2_BLOCKS_PER_GROUP(fs->super));
 197         if (fs->group_desc_count == 0)
 198                 return EXT2_ET_TOOSMALL;
 199         fs->desc_blocks = ext2fs_div_ceil(fs->group_desc_count,
 200                                           EXT2_DESC_PER_BLOCK(fs->super));
 201
 202         /*
 203          * Overhead is the number of bookkeeping blocks per group.  It
 204          * includes the superblock backup, the group descriptor
 205          * backups, the inode bitmap, the block bitmap, and the inode
 206          * table.
 207          */
 208         overhead = (int) (2 + fs->inode_blocks_per_group);
 209
 210         if (ext2fs_bg_has_super(fs, fs->group_desc_count - 1))
 211                 overhead += 1 + fs->desc_blocks +
 212                         fs->super->s_reserved_gdt_blocks;
 213
 214         /*
 215          * See if the last group is big enough to support the
 216          * necessary data structures.  If not, we need to get rid of
 217          * it.
 218          */
 219         rem = (fs->super->s_blocks_count - fs->super->s_first_data_block) %
 220                 fs->super->s_blocks_per_group;
 221         if ((fs->group_desc_count == 1) && rem && (rem < overhead))
 222                 return EXT2_ET_TOOSMALL;
 223         if (rem && (rem < overhead+50)) {
 224                 fs->super->s_blocks_count -= rem;
 225                 goto retry;
 226         }
 227         /*
 228          * Adjust the number of inodes
 229          */
 230         new_inodes =(__u64)fs->super->s_inodes_per_group * fs->group_desc_count;
 231         if (new_inodes > ~0U) {
 232                 fprintf(stderr, _("inodes (%llu) must be less than %u"),
 233                                    new_inodes, ~0U);
 234                 return EXT2_ET_TOO_MANY_INODES;
 235         }
 236         fs->super->s_inodes_count = fs->super->s_inodes_per_group *
 237                 fs->group_desc_count;
 238
 239         /*
 240          * Adjust the number of free blocks
 241          */
 242         blk = old_fs->super->s_blocks_count;
 243         if (blk > fs->super->s_blocks_count)
 244                 fs->super->s_free_blocks_count -=
 245                         (blk - fs->super->s_blocks_count);
 246         else
 247                 fs->super->s_free_blocks_count +=
 248                         (fs->super->s_blocks_count - blk);
 249
 250         /*
 251          * Adjust the number of reserved blocks
 252          */
 253         blk = (__u64)old_fs->super->s_r_blocks_count * 100 /
 254                 old_fs->super->s_blocks_count;
 255         fs->super->s_r_blocks_count = e2p_percent(blk,
 256                                                   fs->super->s_blocks_count);
 257
 258         /*
 259          * Adjust the bitmaps for size
 260          */
 261         retval = ext2fs_resize_inode_bitmap(fs->super->s_inodes_count,
 262                                             fs->super->s_inodes_count,
 263                                             fs->inode_map);
 264         if (retval) goto errout;
 265
 266         real_end = ((EXT2_BLOCKS_PER_GROUP(fs->super)
 267                      * fs->group_desc_count)) - 1 +
 268                              fs->super->s_first_data_block;
 269         retval = ext2fs_resize_block_bitmap(fs->super->s_blocks_count-1,
 270                                             real_end, fs->block_map);
 271
 272         if (retval) goto errout;
 273
 274         /*
 275          * Reallocate the group descriptors as necessary.
 276          */
 277         if (old_fs->desc_blocks != fs->desc_blocks) {
 278                 retval = ext2fs_resize_mem(old_fs->desc_blocks *
 279                                            fs->blocksize,
 280                                            fs->desc_blocks * fs->blocksize,
 281                                            &fs->group_desc);
 282                 if (retval)
 283                         goto errout;
 284                 if (fs->desc_blocks > old_fs->desc_blocks)
 285                         memset((char *) fs->group_desc +
 286                                (old_fs->desc_blocks * fs->blocksize), 0,
 287                                (fs->desc_blocks - old_fs->desc_blocks) *
 288                                fs->blocksize);
 289         }
 290
 291         /*
 292          * If the resize_inode feature is set, and we are changing the
 293          * number of descriptor blocks, then adjust
 294          * s_reserved_gdt_blocks if possible to avoid needing to move
 295          * the inode table either now or in the future.
 296          */
 297         if ((fs->super->s_feature_compat &
 298              EXT2_FEATURE_COMPAT_RESIZE_INODE) &&
 299             (old_fs->desc_blocks != fs->desc_blocks)) {
 300                 int new;
 301
 302                 new = ((int) fs->super->s_reserved_gdt_blocks) +
 303                         (old_fs->desc_blocks - fs->desc_blocks);
 304                 if (new < 0)
 305                         new = 0;
 306                 if (new > fs->blocksize/4)
 307                         new = fs->blocksize/4;
 308                 fs->super->s_reserved_gdt_blocks = new;
 309                 if (new == 0)
 310                         fs->super->s_feature_compat &=
 311                                 ~EXT2_FEATURE_COMPAT_RESIZE_INODE;
 312         }
 313
 314         /*
 315          * If we are shrinking the number block groups, we're done and
 316          * can exit now.
 317          */
 318         if (old_fs->group_desc_count > fs->group_desc_count) {
 319                 retval = 0;
 320                 goto errout;
 321         }
 322
 323         /*
 324          * Fix the count of the last (old) block group
 325          */
 326         old_numblocks = (old_fs->super->s_blocks_count -
 327                          old_fs->super->s_first_data_block) %
 328                                  old_fs->super->s_blocks_per_group;
 329         if (!old_numblocks)
 330                 old_numblocks = old_fs->super->s_blocks_per_group;
 331         if (old_fs->group_desc_count == fs->group_desc_count) {
 332                 numblocks = (fs->super->s_blocks_count -
 333                              fs->super->s_first_data_block) %
 334                         fs->super->s_blocks_per_group;
 335                 if (!numblocks)
 336                         numblocks = fs->super->s_blocks_per_group;
 337         } else
 338                 numblocks = fs->super->s_blocks_per_group;
 339         i = old_fs->group_desc_count - 1;
 340         fs->group_desc[i].bg_free_blocks_count += (numblocks-old_numblocks);
 341
 342         /*
 343          * If the number of block groups is staying the same, we're
 344          * done and can exit now.  (If the number block groups is
 345          * shrinking, we had exited earlier.)
 346          */
 347         if (old_fs->group_desc_count >= fs->group_desc_count) {
 348                 retval = 0;
 349                 goto errout;
 350         }
 351
 352         /*
 353          * Initialize the new block group descriptors
 354          */
 355         group_block = fs->super->s_first_data_block +
 356                 old_fs->group_desc_count * fs->super->s_blocks_per_group;
 357
 358         adj = old_fs->group_desc_count;
 359         max_group = fs->group_desc_count - adj;
 360         if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
 361                 old_desc_blocks = fs->super->s_first_meta_bg;
 362         else
 363                 old_desc_blocks = fs->desc_blocks +
 364                         fs->super->s_reserved_gdt_blocks;
 365         for (i = old_fs->group_desc_count;
 366              i < fs->group_desc_count; i++) {
 367                 memset(&fs->group_desc[i], 0,
 368                        sizeof(struct ext2_group_desc));
 369                 adjblocks = 0;
 370
 371                 if (i == fs->group_desc_count-1) {
 372                         numblocks = (fs->super->s_blocks_count -
 373                                      fs->super->s_first_data_block) %
 374                                              fs->super->s_blocks_per_group;
 375                         if (!numblocks)
 376                                 numblocks = fs->super->s_blocks_per_group;
 377                 } else
 378                         numblocks = fs->super->s_blocks_per_group;
 379
 380                 has_super = ext2fs_bg_has_super(fs, i);
 381                 if (has_super) {
 382                         ext2fs_mark_block_bitmap(fs->block_map, group_block);
 383                         adjblocks++;
 384                 }
 385                 meta_bg_size = (fs->blocksize /
 386                                 sizeof (struct ext2_group_desc));
 387                 meta_bg = i / meta_bg_size;
 388                 if (!(fs->super->s_feature_incompat &
 389                       EXT2_FEATURE_INCOMPAT_META_BG) ||
 390                     (meta_bg < fs->super->s_first_meta_bg)) {
 391                         if (has_super) {
 392                                 for (j=0; j < old_desc_blocks; j++)
 393                                         ext2fs_mark_block_bitmap(fs->block_map,
 394                                                          group_block + 1 + j);
 395                                 adjblocks += old_desc_blocks;
 396                         }
 397                 } else {
 398                         if (has_super)
 399                                 has_super = 1;
 400                         if (((i % meta_bg_size) == 0) ||
 401                             ((i % meta_bg_size) == 1) ||
 402                             ((i % meta_bg_size) == (meta_bg_size-1)))
 403                                 ext2fs_mark_block_bitmap(fs->block_map,
 404                                                  group_block + has_super);
 405                 }
 406
 407                 adjblocks += 2 + fs->inode_blocks_per_group;
 408
 409                 numblocks -= adjblocks;
 410                 fs->super->s_free_blocks_count -= adjblocks;
 411                 fs->super->s_free_inodes_count +=
 412                         fs->super->s_inodes_per_group;
 413                 fs->group_desc[i].bg_free_blocks_count = numblocks;
 414                 fs->group_desc[i].bg_free_inodes_count =
 415                         fs->super->s_inodes_per_group;
 416                 fs->group_desc[i].bg_used_dirs_count = 0;
 417
 418                 retval = ext2fs_allocate_group_table(fs, i, 0);
 419                 if (retval) goto errout;
 420
 421                 group_block += fs->super->s_blocks_per_group;
 422         }
 423         retval = 0;
 424
 425 errout:
 426         return (retval);
 427 }
 428
 429 /*
 430  * This routine adjusts the superblock and other data structures, both
 431  * in disk as well as in memory...
 432  */
 433 static errcode_t adjust_superblock(ext2_resize_t rfs, blk_t new_size)
 434 {
 435         ext2_filsys fs;
 436         int             adj = 0;
 437         errcode_t       retval;
 438         blk_t           group_block;
 439         unsigned long   i;
 440         unsigned long   max_group;
 441
 442         fs = rfs->new_fs;
 443         ext2fs_mark_super_dirty(fs);
 444         ext2fs_mark_bb_dirty(fs);
 445         ext2fs_mark_ib_dirty(fs);
 446
 447         retval = adjust_fs_info(fs, rfs->old_fs, new_size);
 448         if (retval)
 449                 goto errout;
 450
 451         /*
 452          * Check to make sure there are enough inodes
 453          */
 454         if ((rfs->old_fs->super->s_inodes_count -
 455              rfs->old_fs->super->s_free_inodes_count) >
 456             rfs->new_fs->super->s_inodes_count) {
 457                 retval = ENOSPC;
 458                 goto errout;
 459         }
 460
 461         /*
 462          * If we are shrinking the number block groups, we're done and
 463          * can exit now.
 464          */
 465         if (rfs->old_fs->group_desc_count > fs->group_desc_count) {
 466                 retval = 0;
 467                 goto errout;
 468         }
 469
 470         /*
 471          * If the number of block groups is staying the same, we're
 472          * done and can exit now.  (If the number block groups is
 473          * shrinking, we had exited earlier.)
 474          */
 475         if (rfs->old_fs->group_desc_count >= fs->group_desc_count) {
 476                 retval = 0;
 477                 goto errout;
 478         }
 479
 480         /*
 481          * Initialize the new block group descriptors
 482          */
 483         retval = ext2fs_get_mem(fs->blocksize * fs->inode_blocks_per_group,
 484                                 &rfs->itable_buf);
 485         if (retval)
 486                 goto errout;
 487
 488         memset(rfs->itable_buf, 0, fs->blocksize * fs->inode_blocks_per_group);
 489         group_block = fs->super->s_first_data_block +
 490                 rfs->old_fs->group_desc_count * fs->super->s_blocks_per_group;
 491
 492         adj = rfs->old_fs->group_desc_count;
 493         max_group = fs->group_desc_count - adj;
 494         if (rfs->progress) {
 495                 retval = rfs->progress(rfs, E2_RSZ_EXTEND_ITABLE_PASS,
 496                                        0, max_group);
 497                 if (retval)
 498                         goto errout;
 499         }
 500         for (i = rfs->old_fs->group_desc_count;
 501              i < fs->group_desc_count; i++) {
 502                 /*
 503                  * Write out the new inode table
 504                  */
 505                 retval = io_channel_write_blk(fs->io,
 506                                               fs->group_desc[i].bg_inode_table,
 507                                               fs->inode_blocks_per_group,
 508                                               rfs->itable_buf);
 509                 if (retval) goto errout;
 510
 511                 io_channel_flush(fs->io);
 512                 if (rfs->progress) {
 513                         retval = rfs->progress(rfs, E2_RSZ_EXTEND_ITABLE_PASS,
 514                                                i - adj + 1, max_group);
 515                         if (retval)
 516                                 goto errout;
 517                 }
 518                 group_block += fs->super->s_blocks_per_group;
 519         }
 520         io_channel_flush(fs->io);
 521         retval = 0;
 522
 523 errout:
 524         return retval;
 525 }
 526
 527 /* --------------------------------------------------------------------
 528  *
 529  * Resize processing, phase 2.
 530  *
 531  * In this phase we adjust determine which blocks need to be moved, in
 532  * blocks_to_move().  We then copy the blocks to their ultimate new
 533  * destinations using block_mover().  Since we are copying blocks to
 534  * their new locations, again during this pass we can abort without
 535  * any problems.
 536  * --------------------------------------------------------------------
 537  */
 538
 539 /*
 540  * This helper function creates a block bitmap with all of the
 541  * filesystem meta-data blocks.
 542  */
 543 static errcode_t mark_table_blocks(ext2_filsys fs,
 544                                    ext2fs_block_bitmap bmap)
 545 {
 546         blk_t                   b;
 547         unsigned int            j;
 548         dgrp_t                  i;
 549         unsigned long           meta_bg_size;
 550         unsigned int            old_desc_blocks;
 551
 552         meta_bg_size = (fs->blocksize / sizeof (struct ext2_group_desc));
 553         if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
 554                 old_desc_blocks = fs->super->s_first_meta_bg;
 555         else
 556                 old_desc_blocks = fs->desc_blocks +
 557                         fs->super->s_reserved_gdt_blocks;
 558         for (i = 0; i < fs->group_desc_count; i++) {
 559                 ext2fs_reserve_super_and_bgd(fs, i, bmap);
 560
 561                 /*
 562                  * Mark the blocks used for the inode table
 563                  */
 564                 for (j = 0, b = fs->group_desc[i].bg_inode_table;
 565                      j < (unsigned int) fs->inode_blocks_per_group;
 566                      j++, b++)
 567                         ext2fs_mark_block_bitmap(bmap, b);
 568
 569                 /*
 570                  * Mark block used for the block bitmap
 571                  */
 572                 ext2fs_mark_block_bitmap(bmap,
 573                                          fs->group_desc[i].bg_block_bitmap);
 574
 575                 /*
 576                  * Mark block used for the inode bitmap
 577                  */
 578                 ext2fs_mark_block_bitmap(bmap,
 579                                          fs->group_desc[i].bg_inode_bitmap);
 580         }
 581         return 0;
 582 }
 583
 584 /*
 585  * This function checks to see if a particular block (either a
 586  * superblock or a block group descriptor) overlaps with an inode or
 587  * block bitmap block, or with the inode table.
 588  */
 589 static void mark_fs_metablock(ext2_resize_t rfs,
 590                               ext2fs_block_bitmap meta_bmap,
 591                               int group, blk_t blk)
 592 {
 593         ext2_filsys     fs = rfs->new_fs;
 594
 595         ext2fs_mark_block_bitmap(rfs->reserve_blocks, blk);
 596         ext2fs_mark_block_bitmap(fs->block_map, blk);
 597
 598         /*
 599          * Check to see if we overlap with the inode or block bitmap,
 600          * or the inode tables.  If not, and the block is in use, then
 601          * mark it as a block to be moved.
 602          */
 603         if (IS_BLOCK_BM(fs, group, blk)) {
 604                 FS_BLOCK_BM(fs, group) = 0;
 605                 rfs->needed_blocks++;
 606         } else if (IS_INODE_BM(fs, group, blk)) {
 607                 FS_INODE_BM(fs, group) = 0;
 608                 rfs->needed_blocks++;
 609         } else if (IS_INODE_TB(fs, group, blk)) {
 610                 FS_INODE_TB(fs, group) = 0;
 611                 rfs->needed_blocks++;
 612         } else if (ext2fs_test_block_bitmap(rfs->old_fs->block_map, blk) &&
 613                    !ext2fs_test_block_bitmap(meta_bmap, blk)) {
 614                 ext2fs_mark_block_bitmap(rfs->move_blocks, blk);
 615                 rfs->needed_blocks++;
 616         }
 617 }
 618
 619
 620 /*
 621  * This routine marks and unmarks reserved blocks in the new block
 622  * bitmap.  It also determines which blocks need to be moved and
 623  * places this information into the move_blocks bitmap.
 624  */
 625 static errcode_t blocks_to_move(ext2_resize_t rfs)
 626 {
 627         int             j, has_super;
 628         dgrp_t          i, max_groups;
 629         blk_t           blk, group_blk;
 630         unsigned long   old_blocks, new_blocks;
 631         unsigned int    meta_bg, meta_bg_size;
 632         errcode_t       retval;
 633         ext2_filsys     fs, old_fs;
 634         ext2fs_block_bitmap     meta_bmap;
 635
 636         fs = rfs->new_fs;
 637         old_fs = rfs->old_fs;
 638         if (old_fs->super->s_blocks_count > fs->super->s_blocks_count)
 639                 fs = rfs->old_fs;
 640
 641         retval = ext2fs_allocate_block_bitmap(fs, _("reserved blocks"),
 642                                               &rfs->reserve_blocks);
 643         if (retval)
 644                 return retval;
 645
 646         retval = ext2fs_allocate_block_bitmap(fs, _("blocks to be moved"),
 647                                               &rfs->move_blocks);
 648         if (retval)
 649                 return retval;
 650
 651         retval = ext2fs_allocate_block_bitmap(fs, _("meta-data blocks"),
 652                                               &meta_bmap);
 653         if (retval)
 654                 return retval;
 655
 656         retval = mark_table_blocks(old_fs, meta_bmap);
 657         if (retval)
 658                 return retval;
 659
 660         fs = rfs->new_fs;
 661
 662         /*
 663          * If we're shrinking the filesystem, we need to move all of
 664          * the blocks that don't fit any more
 665          */
 666         for (blk = fs->super->s_blocks_count;
 667              blk < old_fs->super->s_blocks_count; blk++) {
 668                 if (ext2fs_test_block_bitmap(old_fs->block_map, blk) &&
 669                     !ext2fs_test_block_bitmap(meta_bmap, blk)) {
 670                         ext2fs_mark_block_bitmap(rfs->move_blocks, blk);
 671                         rfs->needed_blocks++;
 672                 }
 673                 ext2fs_mark_block_bitmap(rfs->reserve_blocks, blk);
 674         }
 675
 676         if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG) {
 677                 old_blocks = old_fs->super->s_first_meta_bg;
 678                 new_blocks = fs->super->s_first_meta_bg;
 679         } else {
 680                 old_blocks = old_fs->desc_blocks + old_fs->super->s_reserved_gdt_blocks;
 681                 new_blocks = fs->desc_blocks + fs->super->s_reserved_gdt_blocks;
 682         }
 683
 684         if (old_blocks == new_blocks) {
 685                 retval = 0;
 686                 goto errout;
 687         }
 688
 689         max_groups = fs->group_desc_count;
 690         if (max_groups > old_fs->group_desc_count)
 691                 max_groups = old_fs->group_desc_count;
 692         group_blk = old_fs->super->s_first_data_block;
 693         /*
 694          * If we're reducing the number of descriptor blocks, this
 695          * makes life easy.  :-)   We just have to mark some extra
 696          * blocks as free.
 697          */
 698         if (old_blocks > new_blocks) {
 699                 for (i = 0; i < max_groups; i++) {
 700                         if (!ext2fs_bg_has_super(fs, i)) {
 701                                 group_blk += fs->super->s_blocks_per_group;
 702                                 continue;
 703                         }
 704                         for (blk = group_blk+1+new_blocks;
 705                              blk < group_blk+1+old_blocks; blk++) {
 706                                 ext2fs_unmark_block_bitmap(fs->block_map,
 707                                                            blk);
 708                                 rfs->needed_blocks--;
 709                         }
 710                         group_blk += fs->super->s_blocks_per_group;
 711                 }
 712                 retval = 0;
 713                 goto errout;
 714         }
 715         /*
 716          * If we're increasing the number of descriptor blocks, life
 717          * gets interesting....
 718          */
 719         meta_bg_size = (fs->blocksize / sizeof (struct ext2_group_desc));
 720         for (i = 0; i < max_groups; i++) {
 721                 has_super = ext2fs_bg_has_super(fs, i);
 722                 if (has_super)
 723                         mark_fs_metablock(rfs, meta_bmap, i, group_blk);
 724
 725                 meta_bg = i / meta_bg_size;
 726                 if (!(fs->super->s_feature_incompat &
 727                       EXT2_FEATURE_INCOMPAT_META_BG) ||
 728                     (meta_bg < fs->super->s_first_meta_bg)) {
 729                         if (has_super) {
 730                                 for (blk = group_blk+1;
 731                                      blk < group_blk + 1 + new_blocks; blk++)
 732                                         mark_fs_metablock(rfs, meta_bmap,
 733                                                           i, blk);
 734                         }
 735                 } else {
 736                         if (has_super)
 737                                 has_super = 1;
 738                         if (((i % meta_bg_size) == 0) ||
 739                             ((i % meta_bg_size) == 1) ||
 740                             ((i % meta_bg_size) == (meta_bg_size-1)))
 741                                 mark_fs_metablock(rfs, meta_bmap, i,
 742                                                   group_blk + has_super);
 743                 }
 744
 745                 if (fs->group_desc[i].bg_inode_table &&
 746                     fs->group_desc[i].bg_inode_bitmap &&
 747                     fs->group_desc[i].bg_block_bitmap)
 748                         goto next_group;
 749
 750                 /*
 751                  * Reserve the existing meta blocks that we know
 752                  * aren't to be moved.
 753                  */
 754                 if (fs->group_desc[i].bg_block_bitmap)
 755                         ext2fs_mark_block_bitmap(rfs->reserve_blocks,
 756                                  fs->group_desc[i].bg_block_bitmap);
 757                 if (fs->group_desc[i].bg_inode_bitmap)
 758                         ext2fs_mark_block_bitmap(rfs->reserve_blocks,
 759                                  fs->group_desc[i].bg_inode_bitmap);
 760                 if (fs->group_desc[i].bg_inode_table)
 761                         for (blk = fs->group_desc[i].bg_inode_table, j=0;
 762                              j < fs->inode_blocks_per_group ; j++, blk++)
 763                                 ext2fs_mark_block_bitmap(rfs->reserve_blocks,
 764                                                          blk);
 765
 766                 /*
 767                  * Allocate the missing data structures
 768                  */
 769                 retval = ext2fs_allocate_group_table(fs, i,
 770                                                      rfs->reserve_blocks);
 771                 if (retval)
 772                         goto errout;
 773
 774                 /*
 775                  * For those structures that have changed, we need to
 776                  * do bookkeepping.
 777                  */
 778                 if (FS_BLOCK_BM(old_fs, i) !=
 779                     (blk = FS_BLOCK_BM(fs, i))) {
 780                         ext2fs_mark_block_bitmap(fs->block_map, blk);
 781                         if (ext2fs_test_block_bitmap(old_fs->block_map, blk) &&
 782                             !ext2fs_test_block_bitmap(meta_bmap, blk))
 783                                 ext2fs_mark_block_bitmap(rfs->move_blocks,
 784                                                          blk);
 785                 }
 786                 if (FS_INODE_BM(old_fs, i) !=
 787                     (blk = FS_INODE_BM(fs, i))) {
 788                         ext2fs_mark_block_bitmap(fs->block_map, blk);
 789                         if (ext2fs_test_block_bitmap(old_fs->block_map, blk) &&
 790                             !ext2fs_test_block_bitmap(meta_bmap, blk))
 791                                 ext2fs_mark_block_bitmap(rfs->move_blocks,
 792                                                          blk);
 793                 }
 794
 795                 /*
 796                  * The inode table, if we need to relocate it, is
 797                  * handled specially.  We have to reserve the blocks
 798                  * for both the old and the new inode table, since we
 799                  * can't have the inode table be destroyed during the
 800                  * block relocation phase.
 801                  */
 802                 if (FS_INODE_TB(fs, i) == FS_INODE_TB(old_fs, i))
 803                         goto next_group; /* inode table not moved */
 804
 805                 rfs->needed_blocks += fs->inode_blocks_per_group;
 806
 807                 /*
 808                  * Mark the new inode table as in use in the new block
 809                  * allocation bitmap, and move any blocks that might
 810                  * be necessary.
 811                  */
 812                 for (blk = fs->group_desc[i].bg_inode_table, j=0;
 813                      j < fs->inode_blocks_per_group ; j++, blk++) {
 814                         ext2fs_mark_block_bitmap(fs->block_map, blk);
 815                         if (ext2fs_test_block_bitmap(old_fs->block_map, blk) &&
 816                             !ext2fs_test_block_bitmap(meta_bmap, blk))
 817                                 ext2fs_mark_block_bitmap(rfs->move_blocks,
 818                                                          blk);
 819                 }
 820
 821                 /*
 822                  * Make sure the old inode table is reserved in the
 823                  * block reservation bitmap.
 824                  */
 825                 for (blk = rfs->old_fs->group_desc[i].bg_inode_table, j=0;
 826                      j < fs->inode_blocks_per_group ; j++, blk++)
 827                         ext2fs_mark_block_bitmap(rfs->reserve_blocks, blk);
 828
 829         next_group:
 830                 group_blk += rfs->new_fs->super->s_blocks_per_group;
 831         }
 832         retval = 0;
 833
 834 errout:
 835         if (meta_bmap)
 836                 ext2fs_free_block_bitmap(meta_bmap);
 837
 838         return retval;
 839 }
 840
 841 /*
 842  * This helper function tries to allocate a new block.  We try to
 843  * avoid hitting the original group descriptor blocks at least at
 844  * first, since we want to make it possible to recover from a badly
 845  * aborted resize operation as much as possible.
 846  *
 847  * In the future, I may further modify this routine to balance out
 848  * where we get the new blocks across the various block groups.
 849  * Ideally we would allocate blocks that corresponded with the block
 850  * group of the containing inode, and keep contiguous blocks
 851  * together.  However, this very difficult to do efficiently, since we
 852  * don't have the necessary information up front.
 853  */
 854
 855 #define AVOID_OLD       1
 856 #define DESPERATION     2
 857
 858 static void init_block_alloc(ext2_resize_t rfs)
 859 {
 860         rfs->alloc_state = AVOID_OLD;
 861         rfs->new_blk = rfs->new_fs->super->s_first_data_block;
 862 #if 0
 863         /* HACK for testing */
 864         if (rfs->new_fs->super->s_blocks_count >
 865             rfs->old_fs->super->s_blocks_count)
 866                 rfs->new_blk = rfs->old_fs->super->s_blocks_count;
 867 #endif
 868 }
 869
 870 static blk_t get_new_block(ext2_resize_t rfs)
 871 {
 872         ext2_filsys     fs = rfs->new_fs;
 873
 874         while (1) {
 875                 if (rfs->new_blk >= fs->super->s_blocks_count) {
 876                         if (rfs->alloc_state == DESPERATION)
 877                                 return 0;
 878
 879 #ifdef RESIZE2FS_DEBUG
 880                         if (rfs->flags & RESIZE_DEBUG_BMOVE)
 881                                 printf("Going into desperation mode "
 882                                        "for block allocations\n");
 883 #endif
 884                         rfs->alloc_state = DESPERATION;
 885                         rfs->new_blk = fs->super->s_first_data_block;
 886                         continue;
 887                 }
 888                 if (ext2fs_test_block_bitmap(fs->block_map, rfs->new_blk) ||
 889                     ext2fs_test_block_bitmap(rfs->reserve_blocks,
 890                                              rfs->new_blk) ||
 891                     ((rfs->alloc_state == AVOID_OLD) &&
 892                      (rfs->new_blk < rfs->old_fs->super->s_blocks_count) &&
 893                      ext2fs_test_block_bitmap(rfs->old_fs->block_map,
 894                                               rfs->new_blk))) {
 895                         rfs->new_blk++;
 896                         continue;
 897                 }
 898                 return rfs->new_blk;
 899         }
 900 }
 901
 902 static errcode_t block_mover(ext2_resize_t rfs)
 903 {
 904         blk_t                   blk, old_blk, new_blk;
 905         ext2_filsys             fs = rfs->new_fs;
 906         ext2_filsys             old_fs = rfs->old_fs;
 907         errcode_t               retval;
 908         int                     size, c;
 909         int                     to_move, moved;
 910         ext2_badblocks_list     badblock_list = 0;
 911         int                     bb_modified = 0;
 912
 913         retval = ext2fs_read_bb_inode(old_fs, &badblock_list);
 914         if (retval)
 915                 return retval;
 916
 917         new_blk = fs->super->s_first_data_block;
 918         if (!rfs->itable_buf) {
 919                 retval = ext2fs_get_mem(fs->blocksize *
 920                                         fs->inode_blocks_per_group,
 921                                         &rfs->itable_buf);
 922                 if (retval)
 923                         return retval;
 924         }
 925         retval = ext2fs_create_extent_table(&rfs->bmap, 0);
 926         if (retval)
 927                 return retval;
 928
 929         /*
 930          * The first step is to figure out where all of the blocks
 931          * will go.
 932          */
 933         to_move = moved = 0;
 934         init_block_alloc(rfs);
 935         for (blk = old_fs->super->s_first_data_block;
 936              blk < old_fs->super->s_blocks_count; blk++) {
 937                 if (!ext2fs_test_block_bitmap(old_fs->block_map, blk))
 938                         continue;
 939                 if (!ext2fs_test_block_bitmap(rfs->move_blocks, blk))
 940                         continue;
 941                 if (ext2fs_badblocks_list_test(badblock_list, blk)) {
 942                         ext2fs_badblocks_list_del(badblock_list, blk);
 943                         bb_modified++;
 944                         continue;
 945                 }
 946
 947                 new_blk = get_new_block(rfs);
 948                 if (!new_blk) {
 949                         retval = ENOSPC;
 950                         goto errout;
 951                 }
 952                 ext2fs_mark_block_bitmap(fs->block_map, new_blk);
 953                 ext2fs_add_extent_entry(rfs->bmap, blk, new_blk);
 954                 to_move++;
 955         }
 956
 957         if (to_move == 0) {
 958                 if (rfs->bmap) {
 959                         ext2fs_free_extent_table(rfs->bmap);
 960                         rfs->bmap = 0;
 961                 }
 962                 retval = 0;
 963                 goto errout;
 964         }
 965
 966         /*
 967          * Step two is to actually move the blocks
 968          */
 969         retval =  ext2fs_iterate_extent(rfs->bmap, 0, 0, 0);
 970         if (retval) goto errout;
 971
 972         if (rfs->progress) {
 973                 retval = (rfs->progress)(rfs, E2_RSZ_BLOCK_RELOC_PASS,
 974                                          0, to_move);
 975                 if (retval)
 976                         goto errout;
 977         }
 978         while (1) {
 979                 retval = ext2fs_iterate_extent(rfs->bmap, &old_blk, &new_blk, &size);
 980                 if (retval) goto errout;
 981                 if (!size)
 982                         break;
 983 #ifdef RESIZE2FS_DEBUG
 984                 if (rfs->flags & RESIZE_DEBUG_BMOVE)
 985                         printf("Moving %d blocks %u->%u\n",
 986                                size, old_blk, new_blk);
 987 #endif
 988                 do {
 989                         c = size;
 990                         if (c > fs->inode_blocks_per_group)
 991                                 c = fs->inode_blocks_per_group;
 992                         retval = io_channel_read_blk(fs->io, old_blk, c,
 993                                                      rfs->itable_buf);
 994                         if (retval) goto errout;
 995                         retval = io_channel_write_blk(fs->io, new_blk, c,
 996                                                       rfs->itable_buf);
 997                         if (retval) goto errout;
 998                         size -= c;
 999                         new_blk += c;
1000                         old_blk += c;
1001                         moved += c;
1002                         if (rfs->progress) {
1003                                 io_channel_flush(fs->io);
1004                                 retval = (rfs->progress)(rfs,
1005                                                 E2_RSZ_BLOCK_RELOC_PASS,
1006                                                 moved, to_move);
1007                                 if (retval)
1008                                         goto errout;
1009                         }
1010                 } while (size > 0);
1011                 io_channel_flush(fs->io);
1012         }
1013
1014 errout:
1015         if (badblock_list) {
1016                 if (!retval && bb_modified)
1017                         retval = ext2fs_update_bb_inode(old_fs,
1018                                                         badblock_list);
1019                 ext2fs_badblocks_list_free(badblock_list);
1020         }
1021         return retval;
1022 }
1023
1024
1025 /* --------------------------------------------------------------------
1026  *
1027  * Resize processing, phase 3
1028  *
1029  * --------------------------------------------------------------------
1030  */
1031
1032
1033 struct process_block_struct {
1034         ext2_resize_t           rfs;
1035         ext2_ino_t              ino;
1036         struct ext2_inode *     inode;
1037         errcode_t               error;
1038         int                     is_dir;
1039         int                     changed;
1040 };
1041
1042 static int process_block(ext2_filsys fs, blk_t  *block_nr,
1043                          e2_blkcnt_t blockcnt,
1044                          blk_t ref_block EXT2FS_ATTR((unused)),
1045                          int ref_offset EXT2FS_ATTR((unused)), void *priv_data)
1046 {
1047         struct process_block_struct *pb;
1048         errcode_t       retval;
1049         blk_t           block, new_block;
1050         int             ret = 0;
1051
1052         pb = (struct process_block_struct *) priv_data;
1053         block = *block_nr;
1054         if (pb->rfs->bmap) {
1055                 new_block = ext2fs_extent_translate(pb->rfs->bmap, block);
1056                 if (new_block) {
1057                         *block_nr = new_block;
1058                         ret |= BLOCK_CHANGED;
1059                         pb->changed = 1;
1060 #ifdef RESIZE2FS_DEBUG
1061                         if (pb->rfs->flags & RESIZE_DEBUG_BMOVE)
1062                                 printf("ino=%u, blockcnt=%lld, %u->%u\n",
1063                                        pb->ino, blockcnt, block, new_block);
1064 #endif
1065                         block = new_block;
1066                 }
1067         }
1068         if (pb->is_dir) {
1069                 retval = ext2fs_add_dir_block(fs->dblist, pb->ino,
1070                                               block, (int) blockcnt);
1071                 if (retval) {
1072                         pb->error = retval;
1073                         ret |= BLOCK_ABORT;
1074                 }
1075         }
1076         return ret;
1077 }
1078
1079 /*
1080  * Progress callback
1081  */
1082 static errcode_t progress_callback(ext2_filsys fs,
1083                                    ext2_inode_scan scan EXT2FS_ATTR((unused)),
1084                                    dgrp_t group, void * priv_data)
1085 {
1086         ext2_resize_t rfs = (ext2_resize_t) priv_data;
1087         errcode_t               retval;
1088
1089         /*
1090          * This check is to protect against old ext2 libraries.  It
1091          * shouldn't be needed against new libraries.
1092          */
1093         if ((group+1) == 0)
1094                 return 0;
1095
1096         if (rfs->progress) {
1097                 io_channel_flush(fs->io);
1098                 retval = (rfs->progress)(rfs, E2_RSZ_INODE_SCAN_PASS,
1099                                          group+1, fs->group_desc_count);
1100                 if (retval)
1101                         return retval;
1102         }
1103
1104         return 0;
1105 }
1106
1107 static errcode_t inode_scan_and_fix(ext2_resize_t rfs)
1108 {
1109         struct process_block_struct     pb;
1110         ext2_ino_t              ino, new_inode;
1111         struct ext2_inode       inode;
1112         ext2_inode_scan         scan = NULL;
1113         errcode_t               retval;
1114         int                     group;
1115         char                    *block_buf = 0;
1116         ext2_ino_t              start_to_move;
1117         blk_t                   orig_size, new_block;
1118
1119         if ((rfs->old_fs->group_desc_count <=
1120              rfs->new_fs->group_desc_count) &&
1121             !rfs->bmap)
1122                 return 0;
1123
1124         /*
1125          * Save the original size of the old filesystem, and
1126          * temporarily set the size to be the new size if the new size
1127          * is larger.  We need to do this to avoid catching an error
1128          * by the block iterator routines
1129          */
1130         orig_size = rfs->old_fs->super->s_blocks_count;
1131         if (orig_size < rfs->new_fs->super->s_blocks_count)
1132                 rfs->old_fs->super->s_blocks_count =
1133                         rfs->new_fs->super->s_blocks_count;
1134
1135         retval = ext2fs_open_inode_scan(rfs->old_fs, 0, &scan);
1136         if (retval) goto errout;
1137
1138         retval = ext2fs_init_dblist(rfs->old_fs, 0);
1139         if (retval) goto errout;
1140         retval = ext2fs_get_mem(rfs->old_fs->blocksize * 3, &block_buf);
1141         if (retval) goto errout;
1142
1143         start_to_move = (rfs->new_fs->group_desc_count *
1144                          rfs->new_fs->super->s_inodes_per_group);
1145
1146         if (rfs->progress) {
1147                 retval = (rfs->progress)(rfs, E2_RSZ_INODE_SCAN_PASS,
1148                                          0, rfs->old_fs->group_desc_count);
1149                 if (retval)
1150                         goto errout;
1151         }
1152         ext2fs_set_inode_callback(scan, progress_callback, (void *) rfs);
1153         pb.rfs = rfs;
1154         pb.inode = &inode;
1155         pb.error = 0;
1156         new_inode = EXT2_FIRST_INODE(rfs->new_fs->super);
1157         /*
1158          * First, copy all of the inodes that need to be moved
1159          * elsewhere in the inode table
1160          */
1161         while (1) {
1162                 retval = ext2fs_get_next_inode(scan, &ino, &inode);
1163                 if (retval) goto errout;
1164                 if (!ino)
1165                         break;
1166
1167                 if (inode.i_links_count == 0 && ino != EXT2_RESIZE_INO)
1168                         continue; /* inode not in use */
1169
1170                 pb.is_dir = LINUX_S_ISDIR(inode.i_mode);
1171                 pb.changed = 0;
1172
1173                 if (inode.i_file_acl && rfs->bmap) {
1174                         new_block = ext2fs_extent_translate(rfs->bmap,
1175                                                             inode.i_file_acl);
1176                         if (new_block) {
1177                                 inode.i_file_acl = new_block;
1178                                 retval = ext2fs_write_inode(rfs->old_fs,
1179                                                             ino, &inode);
1180                                 if (retval) goto errout;
1181                         }
1182                 }
1183
1184                 if (ext2fs_inode_has_valid_blocks(&inode) &&
1185                     (rfs->bmap || pb.is_dir)) {
1186                         pb.ino = ino;
1187                         retval = ext2fs_block_iterate2(rfs->old_fs,
1188                                                        ino, 0, block_buf,
1189                                                        process_block, &pb);
1190                         if (retval)
1191                                 goto errout;
1192                         if (pb.error) {
1193                                 retval = pb.error;
1194                                 goto errout;
1195                         }
1196                 }
1197
1198                 if (ino <= start_to_move)
1199                         continue; /* Don't need to move it. */
1200
1201                 /*
1202                  * Find a new inode
1203                  */
1204                 while (1) {
1205                         if (!ext2fs_test_inode_bitmap(rfs->new_fs->inode_map,
1206                                                       new_inode))
1207                                 break;
1208                         new_inode++;
1209                         if (new_inode > rfs->new_fs->super->s_inodes_count) {
1210                                 retval = ENOSPC;
1211                                 goto errout;
1212                         }
1213                 }
1214                 ext2fs_mark_inode_bitmap(rfs->new_fs->inode_map, new_inode);
1215                 if (pb.changed) {
1216                         /* Get the new version of the inode */
1217                         retval = ext2fs_read_inode(rfs->old_fs, ino, &inode);
1218                         if (retval) goto errout;
1219                 }
1220                 inode.i_ctime = time(0);
1221                 retval = ext2fs_write_inode(rfs->old_fs, new_inode, &inode);
1222                 if (retval) goto errout;
1223
1224                 group = (new_inode-1) / EXT2_INODES_PER_GROUP(rfs->new_fs->super);
1225                 if (LINUX_S_ISDIR(inode.i_mode))
1226                         rfs->new_fs->group_desc[group].bg_used_dirs_count++;
1227
1228 #ifdef RESIZE2FS_DEBUG
1229                 if (rfs->flags & RESIZE_DEBUG_INODEMAP)
1230                         printf("Inode moved %u->%u\n", ino, new_inode);
1231 #endif
1232                 if (!rfs->imap) {
1233                         retval = ext2fs_create_extent_table(&rfs->imap, 0);
1234                         if (retval)
1235                                 goto errout;
1236                 }
1237                 ext2fs_add_extent_entry(rfs->imap, ino, new_inode);
1238         }
1239         io_channel_flush(rfs->old_fs->io);
1240
1241 errout:
1242         rfs->old_fs->super->s_blocks_count = orig_size;
1243         if (rfs->bmap) {
1244                 ext2fs_free_extent_table(rfs->bmap);
1245                 rfs->bmap = 0;
1246         }
1247         if (scan)
1248                 ext2fs_close_inode_scan(scan);
1249         if (block_buf)
1250                 ext2fs_free_mem(&block_buf);
1251         return retval;
1252 }
1253
1254 /* --------------------------------------------------------------------
1255  *
1256  * Resize processing, phase 4.
1257  *
1258  * --------------------------------------------------------------------
1259  */
1260
1261 struct istruct {
1262         ext2_resize_t rfs;
1263         errcode_t       err;
1264         unsigned long   max_dirs;
1265         int             num;
1266 };
1267
1268 static int check_and_change_inodes(ext2_ino_t dir,
1269                                    int entry EXT2FS_ATTR((unused)),
1270                                    struct ext2_dir_entry *dirent, int offset,
1271                                    int  blocksize EXT2FS_ATTR((unused)),
1272                                    char *buf EXT2FS_ATTR((unused)),
1273                                    void *priv_data)
1274 {
1275         struct istruct *is = (struct istruct *) priv_data;
1276         struct ext2_inode       inode;
1277         ext2_ino_t              new_inode;
1278         errcode_t               retval;
1279
1280         if (is->rfs->progress && offset == 0) {
1281                 io_channel_flush(is->rfs->old_fs->io);
1282                 is->err = (is->rfs->progress)(is->rfs,
1283                                               E2_RSZ_INODE_REF_UPD_PASS,
1284                                               ++is->num, is->max_dirs);
1285                 if (is->err)
1286                         return DIRENT_ABORT;
1287         }
1288
1289         if (!dirent->inode)
1290                 return 0;
1291
1292         new_inode = ext2fs_extent_translate(is->rfs->imap, dirent->inode);
1293
1294         if (!new_inode)
1295                 return 0;
1296 #ifdef RESIZE2FS_DEBUG
1297         if (is->rfs->flags & RESIZE_DEBUG_INODEMAP)
1298                 printf("Inode translate (dir=%u, name=%.*s, %u->%u)\n",
1299                        dir, dirent->name_len&0xFF, dirent->name,
1300                        dirent->inode, new_inode);
1301 #endif
1302
1303         dirent->inode = new_inode;
1304
1305         /* Update the directory mtime and ctime */
1306         retval = ext2fs_read_inode(is->rfs->old_fs, dir, &inode);
1307         if (retval == 0) {
1308                 inode.i_mtime = inode.i_ctime = time(0);
1309                 is->err = ext2fs_write_inode(is->rfs->old_fs, dir, &inode);
1310                 if (is->err)
1311                         return DIRENT_ABORT;
1312         }
1313
1314         return DIRENT_CHANGED;
1315 }
1316
1317 static errcode_t inode_ref_fix(ext2_resize_t rfs)
1318 {
1319         errcode_t               retval;
1320         struct istruct          is;
1321
1322         if (!rfs->imap)
1323                 return 0;
1324
1325         /*
1326          * Now, we iterate over all of the directories to update the
1327          * inode references
1328          */
1329         is.num = 0;
1330         is.max_dirs = ext2fs_dblist_count(rfs->old_fs->dblist);
1331         is.rfs = rfs;
1332         is.err = 0;
1333
1334         if (rfs->progress) {
1335                 retval = (rfs->progress)(rfs, E2_RSZ_INODE_REF_UPD_PASS,
1336                                          0, is.max_dirs);
1337                 if (retval)
1338                         goto errout;
1339         }
1340
1341         retval = ext2fs_dblist_dir_iterate(rfs->old_fs->dblist,
1342                                            DIRENT_FLAG_INCLUDE_EMPTY, 0,
1343                                            check_and_change_inodes, &is);
1344         if (retval)
1345                 goto errout;
1346         if (is.err) {
1347                 retval = is.err;
1348                 goto errout;
1349         }
1350
1351 errout:
1352         ext2fs_free_extent_table(rfs->imap);
1353         rfs->imap = 0;
1354         return retval;
1355 }
1356
1357
1358 /* --------------------------------------------------------------------
1359  *
1360  * Resize processing, phase 5.
1361  *
1362  * In this phase we actually move the inode table around, and then
1363  * update the summary statistics.  This is scary, since aborting here
1364  * will potentially scramble the filesystem.  (We are moving the
1365  * inode tables around in place, and so the potential for lost data,
1366  * or at the very least scrambling the mapping between filenames and
1367  * inode numbers is very high in case of a power failure here.)
1368  * --------------------------------------------------------------------
1369  */
1370
1371
1372 /*
1373  * A very scary routine --- this one moves the inode table around!!!
1374  *
1375  * After this you have to use the rfs->new_fs file handle to read and
1376  * write inodes.
1377  */
1378 static errcode_t move_itables(ext2_resize_t rfs)
1379 {
1380         int             n, num, size, diff;
1381         dgrp_t          i, max_groups;
1382         ext2_filsys     fs = rfs->new_fs;
1383         char            *cp;
1384         blk_t           old_blk, new_blk, blk;
1385         errcode_t       retval;
1386         int             j, to_move, moved;
1387
1388         max_groups = fs->group_desc_count;
1389         if (max_groups > rfs->old_fs->group_desc_count)
1390                 max_groups = rfs->old_fs->group_desc_count;
1391
1392         size = fs->blocksize * fs->inode_blocks_per_group;
1393         if (!rfs->itable_buf) {
1394                 retval = ext2fs_get_mem(size, &rfs->itable_buf);
1395                 if (retval)
1396                         return retval;
1397         }
1398
1399         /*
1400          * Figure out how many inode tables we need to move
1401          */
1402         to_move = moved = 0;
1403         for (i=0; i < max_groups; i++)
1404                 if (rfs->old_fs->group_desc[i].bg_inode_table !=
1405                     fs->group_desc[i].bg_inode_table)
1406                         to_move++;
1407
1408         if (to_move == 0)
1409                 return 0;
1410
1411         if (rfs->progress) {
1412                 retval = rfs->progress(rfs, E2_RSZ_MOVE_ITABLE_PASS,
1413                                        0, to_move);
1414                 if (retval)
1415                         goto errout;
1416         }
1417
1418         rfs->old_fs->flags |= EXT2_FLAG_MASTER_SB_ONLY;
1419
1420         for (i=0; i < max_groups; i++) {
1421                 old_blk = rfs->old_fs->group_desc[i].bg_inode_table;
1422                 new_blk = fs->group_desc[i].bg_inode_table;
1423                 diff = new_blk - old_blk;
1424
1425 #ifdef RESIZE2FS_DEBUG
1426                 if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
1427                         printf("Itable move group %d block %u->%u (diff %d)\n",
1428                                i, old_blk, new_blk, diff);
1429 #endif
1430
1431                 if (!diff)
1432                         continue;
1433
1434                 retval = io_channel_read_blk(fs->io, old_blk,
1435                                              fs->inode_blocks_per_group,
1436                                              rfs->itable_buf);
1437                 if (retval)
1438                         goto errout;
1439                 /*
1440                  * The end of the inode table segment often contains
1441                  * all zeros, and we're often only moving the inode
1442                  * table down a block or two.  If so, we can optimize
1443                  * things by not rewriting blocks that we know to be zero
1444                  * already.
1445                  */
1446                 for (cp = rfs->itable_buf+size-1, n=0; n < size; n++, cp--)
1447                         if (*cp)
1448                                 break;
1449                 n = n >> EXT2_BLOCK_SIZE_BITS(fs->super);
1450 #ifdef RESIZE2FS_DEBUG
1451                 if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
1452                         printf("%d blocks of zeros...\n", n);
1453 #endif
1454                 num = fs->inode_blocks_per_group;
1455                 if (n > diff)
1456                         num -= n;
1457
1458                 retval = io_channel_write_blk(fs->io, new_blk,
1459                                               num, rfs->itable_buf);
1460                 if (retval) {
1461                         io_channel_write_blk(fs->io, old_blk,
1462                                              num, rfs->itable_buf);
1463                         goto errout;
1464                 }
1465                 if (n > diff) {
1466                         retval = io_channel_write_blk(fs->io,
1467                               old_blk + fs->inode_blocks_per_group,
1468                               diff, (rfs->itable_buf +
1469                                      (fs->inode_blocks_per_group - diff) *
1470                                      fs->blocksize));
1471                         if (retval)
1472                                 goto errout;
1473                 }
1474
1475                 for (blk = rfs->old_fs->group_desc[i].bg_inode_table, j=0;
1476                      j < fs->inode_blocks_per_group ; j++, blk++)
1477                         ext2fs_unmark_block_bitmap(fs->block_map, blk);
1478
1479                 rfs->old_fs->group_desc[i].bg_inode_table = new_blk;
1480                 ext2fs_mark_super_dirty(rfs->old_fs);
1481                 ext2fs_flush(rfs->old_fs);
1482
1483                 if (rfs->progress) {
1484                         retval = rfs->progress(rfs, E2_RSZ_MOVE_ITABLE_PASS,
1485                                                ++moved, to_move);
1486                         if (retval)
1487                                 goto errout;
1488                 }
1489         }
1490         mark_table_blocks(fs, fs->block_map);
1491         ext2fs_flush(fs);
1492 #ifdef RESIZE2FS_DEBUG
1493         if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
1494                 printf("Inode table move finished.\n");
1495 #endif
1496         return 0;
1497
1498 errout:
1499         return retval;
1500 }
1501
1502 /*
1503  * Fix the resize inode
1504  */
1505 static errcode_t fix_resize_inode(ext2_filsys fs)
1506 {
1507         struct ext2_inode       inode;
1508         errcode_t               retval;
1509         char *                  block_buf;
1510
1511         if (!(fs->super->s_feature_compat &
1512               EXT2_FEATURE_COMPAT_RESIZE_INODE))
1513                 return 0;
1514
1515         retval = ext2fs_get_mem(fs->blocksize, &block_buf);
1516         if (retval) goto errout;
1517
1518         retval = ext2fs_read_inode(fs, EXT2_RESIZE_INO, &inode);
1519         if (retval) goto errout;
1520
1521         inode.i_blocks = fs->blocksize/512;
1522
1523         retval = ext2fs_write_inode(fs, EXT2_RESIZE_INO, &inode);
1524         if (retval) goto errout;
1525
1526         if (!inode.i_block[EXT2_DIND_BLOCK]) {
1527                 /*
1528                  * Avoid zeroing out block #0; that's rude.  This
1529                  * should never happen anyway since the filesystem
1530                  * should be fsck'ed and we assume it is consistent.
1531                  */
1532                 fprintf(stderr,
1533                         _("Should never happen: resize inode corrupt!\n"));
1534                 exit(1);
1535         }
1536
1537         memset(block_buf, 0, fs->blocksize);
1538
1539         retval = io_channel_write_blk(fs->io, inode.i_block[EXT2_DIND_BLOCK],
1540                                       1, block_buf);
1541         if (retval) goto errout;
1542
1543         retval = ext2fs_create_resize_inode(fs);
1544         if (retval)
1545                 goto errout;
1546
1547 errout:
1548         if (block_buf)
1549                 ext2fs_free_mem(&block_buf);
1550         return retval;
1551 }
1552
1553 /*
1554  * Finally, recalculate the summary information
1555  */
1556 static errcode_t ext2fs_calculate_summary_stats(ext2_filsys fs)
1557 {
1558         blk_t           blk;
1559         ext2_ino_t      ino;
1560         unsigned int    group = 0;
1561         unsigned int    count = 0;
1562         int             total_free = 0;
1563         int             group_free = 0;
1564
1565         /*
1566          * First calculate the block statistics
1567          */
1568         for (blk = fs->super->s_first_data_block;
1569              blk < fs->super->s_blocks_count; blk++) {
1570                 if (!ext2fs_fast_test_block_bitmap(fs->block_map, blk)) {
1571                         group_free++;
1572                         total_free++;
1573                 }
1574                 count++;
1575                 if ((count == fs->super->s_blocks_per_group) ||
1576                     (blk == fs->super->s_blocks_count-1)) {
1577                         fs->group_desc[group++].bg_free_blocks_count =
1578                                 group_free;
1579                         count = 0;
1580                         group_free = 0;
1581                 }
1582         }
1583         fs->super->s_free_blocks_count = total_free;
1584
1585         /*
1586          * Next, calculate the inode statistics
1587          */
1588         group_free = 0;
1589         total_free = 0;
1590         count = 0;
1591         group = 0;
1592
1593         /* Protect loop from wrap-around if s_inodes_count maxed */
1594         for (ino = 1; ino <= fs->super->s_inodes_count && ino > 0; ino++) {
1595                 if (!ext2fs_fast_test_inode_bitmap(fs->inode_map, ino)) {
1596                         group_free++;
1597                         total_free++;
1598                 }
1599                 count++;
1600                 if ((count == fs->super->s_inodes_per_group) ||
1601                     (ino == fs->super->s_inodes_count)) {
1602                         fs->group_desc[group++].bg_free_inodes_count =
1603                                 group_free;
1604                         count = 0;
1605                         group_free = 0;
1606                 }
1607         }
1608         fs->super->s_free_inodes_count = total_free;
1609         ext2fs_mark_super_dirty(fs);
1610         return 0;
1611 }