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 Theodore Ts'o
   8  *
   9  * %Begin-Header%
  10  * This file may be redistributed under the terms of the GNU Public
  11  * License.
  12  * %End-Header%
  13  */
  14
  15 /*
  16  * Resizing a filesystem consists of the following phases:
  17  *
  18  *      1.  Adjust superblock and write out new parts of the inode
  19  *              table
  20  *      2.  Determine blocks which need to be relocated, and copy the
  21  *              contents of blocks from their old locations to the new ones.
  22  *      3.  Scan the inode table, doing the following:
  23  *              a.  If blocks have been moved, update the block
  24  *                      pointers in the inodes and indirect blocks to
  25  *                      point at the new block locations.
  26  *              b.  If parts of the inode table need to be evacuated,
  27  *                      copy inodes from their old locations to their
  28  *                      new ones.
  29  *              c.  If (b) needs to be done, note which blocks contain
  30  *                      directory information, since we will need to
  31  *                      update the directory information.
  32  *      4.  Update the directory blocks with the new inode locations.
  33  *      5.  Move the inode tables, if necessary.
  34  */
  35
  36 #include "config.h"
  37 #include "resize2fs.h"
  38 #include <time.h>
  39
  40 #ifdef __linux__                        /* Kludge for debugging */
  41 #define RESIZE2FS_DEBUG
  42 #endif
  43
  44 static void fix_uninit_block_bitmaps(ext2_filsys fs);
  45 static errcode_t adjust_superblock(ext2_resize_t rfs, blk64_t new_size);
  46 static errcode_t blocks_to_move(ext2_resize_t rfs);
  47 static errcode_t block_mover(ext2_resize_t rfs);
  48 static errcode_t inode_scan_and_fix(ext2_resize_t rfs);
  49 static errcode_t inode_ref_fix(ext2_resize_t rfs);
  50 static errcode_t move_itables(ext2_resize_t rfs);
  51 static errcode_t fix_resize_inode(ext2_filsys fs);
  52 static errcode_t ext2fs_calculate_summary_stats(ext2_filsys fs);
  53 static errcode_t fix_sb_journal_backup(ext2_filsys fs);
  54 static errcode_t mark_table_blocks(ext2_filsys fs,
  55                                    ext2fs_block_bitmap bmap);
  56 static errcode_t clear_sparse_super2_last_group(ext2_resize_t rfs);
  57 static errcode_t reserve_sparse_super2_last_group(ext2_resize_t rfs,
  58                                                  ext2fs_block_bitmap meta_bmap);
  59 static errcode_t resize_group_descriptors(ext2_resize_t rfs, blk64_t new_size);
  60 static errcode_t move_bg_metadata(ext2_resize_t rfs);
  61 static errcode_t zero_high_bits_in_inodes(ext2_resize_t rfs);
  62
  63 /*
  64  * Some helper functions to check if a block is in a metadata area
  65  */
  66 static inline int is_block_bm(ext2_filsys fs, unsigned int grp, blk64_t blk)
  67 {
  68         return blk == ext2fs_block_bitmap_loc(fs, grp);
  69 }
  70
  71 static inline int is_inode_bm(ext2_filsys fs, unsigned int grp, blk64_t blk)
  72 {
  73         return blk == ext2fs_inode_bitmap_loc(fs, grp);
  74 }
  75
  76 static int is_inode_tb(ext2_filsys fs, unsigned int grp, blk64_t blk)
  77 {
  78         return blk >= ext2fs_inode_table_loc(fs, grp) &&
  79                blk < (ext2fs_inode_table_loc(fs, grp) +
  80                       fs->inode_blocks_per_group);
  81 }
  82
  83 /* Some bigalloc helper macros which are more succinct... */
  84 #define B2C(x)  EXT2FS_B2C(fs, (x))
  85 #define C2B(x)  EXT2FS_C2B(fs, (x))
  86 #define EQ_CLSTR(x, y) (B2C(x) == B2C(y))
  87 #define LE_CLSTR(x, y) (B2C(x) <= B2C(y))
  88 #define LT_CLSTR(x, y) (B2C(x) <  B2C(y))
  89 #define GE_CLSTR(x, y) (B2C(x) >= B2C(y))
  90 #define GT_CLSTR(x, y) (B2C(x) >  B2C(y))
  91
  92 static int lazy_itable_init;
  93
  94 /*
  95  * This is the top-level routine which does the dirty deed....
  96  */
  97 errcode_t resize_fs(ext2_filsys fs, blk64_t *new_size, int flags,
  98             errcode_t (*progress)(ext2_resize_t rfs, int pass,
  99                                           unsigned long cur,
 100                                           unsigned long max_val))
 101 {
 102         ext2_resize_t   rfs;
 103         errcode_t       retval;
 104         struct resource_track   rtrack, overall_track;
 105
 106         /*
 107          * Create the data structure
 108          */
 109         retval = ext2fs_get_mem(sizeof(struct ext2_resize_struct), &rfs);
 110         if (retval)
 111                 return retval;
 112
 113         memset(rfs, 0, sizeof(struct ext2_resize_struct));
 114         fs->priv_data = rfs;
 115         rfs->old_fs = fs;
 116         rfs->flags = flags;
 117         rfs->itable_buf  = 0;
 118         rfs->progress = progress;
 119
 120         init_resource_track(&overall_track, "overall resize2fs", fs->io);
 121         init_resource_track(&rtrack, "read_bitmaps", fs->io);
 122         retval = ext2fs_read_bitmaps(fs);
 123         if (retval)
 124                 goto errout;
 125         print_resource_track(rfs, &rtrack, fs->io);
 126
 127         fs->super->s_state |= EXT2_ERROR_FS;
 128         ext2fs_mark_super_dirty(fs);
 129         ext2fs_flush(fs);
 130
 131         init_resource_track(&rtrack, "fix_uninit_block_bitmaps 1", fs->io);
 132         fix_uninit_block_bitmaps(fs);
 133         print_resource_track(rfs, &rtrack, fs->io);
 134         retval = ext2fs_dup_handle(fs, &rfs->new_fs);
 135         if (retval)
 136                 goto errout;
 137
 138         init_resource_track(&rtrack, "resize_group_descriptors", fs->io);
 139         retval = resize_group_descriptors(rfs, *new_size);
 140         if (retval)
 141                 goto errout;
 142         print_resource_track(rfs, &rtrack, fs->io);
 143
 144         init_resource_track(&rtrack, "move_bg_metadata", fs->io);
 145         retval = move_bg_metadata(rfs);
 146         if (retval)
 147                 goto errout;
 148         print_resource_track(rfs, &rtrack, fs->io);
 149
 150         init_resource_track(&rtrack, "zero_high_bits_in_metadata", fs->io);
 151         retval = zero_high_bits_in_inodes(rfs);
 152         if (retval)
 153                 goto errout;
 154         print_resource_track(rfs, &rtrack, fs->io);
 155
 156         init_resource_track(&rtrack, "adjust_superblock", fs->io);
 157         retval = adjust_superblock(rfs, *new_size);
 158         if (retval)
 159                 goto errout;
 160         print_resource_track(rfs, &rtrack, fs->io);
 161
 162         init_resource_track(&rtrack, "fix_uninit_block_bitmaps 2", fs->io);
 163         fix_uninit_block_bitmaps(rfs->new_fs);
 164         print_resource_track(rfs, &rtrack, fs->io);
 165         /* Clear the block bitmap uninit flag for the last block group */
 166         ext2fs_bg_flags_clear(rfs->new_fs, rfs->new_fs->group_desc_count - 1,
 167                              EXT2_BG_BLOCK_UNINIT);
 168
 169         *new_size = ext2fs_blocks_count(rfs->new_fs->super);
 170
 171         init_resource_track(&rtrack, "blocks_to_move", fs->io);
 172         retval = blocks_to_move(rfs);
 173         if (retval)
 174                 goto errout;
 175         print_resource_track(rfs, &rtrack, fs->io);
 176
 177 #ifdef RESIZE2FS_DEBUG
 178         if (rfs->flags & RESIZE_DEBUG_BMOVE)
 179                 printf("Number of free blocks: %llu/%llu, Needed: %llu\n",
 180                        ext2fs_free_blocks_count(rfs->old_fs->super),
 181                        ext2fs_free_blocks_count(rfs->new_fs->super),
 182                        rfs->needed_blocks);
 183 #endif
 184
 185         init_resource_track(&rtrack, "block_mover", fs->io);
 186         retval = block_mover(rfs);
 187         if (retval)
 188                 goto errout;
 189         print_resource_track(rfs, &rtrack, fs->io);
 190
 191         init_resource_track(&rtrack, "inode_scan_and_fix", fs->io);
 192         retval = inode_scan_and_fix(rfs);
 193         if (retval)
 194                 goto errout;
 195         print_resource_track(rfs, &rtrack, fs->io);
 196
 197         init_resource_track(&rtrack, "inode_ref_fix", fs->io);
 198         retval = inode_ref_fix(rfs);
 199         if (retval)
 200                 goto errout;
 201         print_resource_track(rfs, &rtrack, fs->io);
 202
 203         init_resource_track(&rtrack, "move_itables", fs->io);
 204         retval = move_itables(rfs);
 205         if (retval)
 206                 goto errout;
 207         print_resource_track(rfs, &rtrack, fs->io);
 208
 209         retval = clear_sparse_super2_last_group(rfs);
 210         if (retval)
 211                 goto errout;
 212
 213         init_resource_track(&rtrack, "calculate_summary_stats", fs->io);
 214         retval = ext2fs_calculate_summary_stats(rfs->new_fs);
 215         if (retval)
 216                 goto errout;
 217         print_resource_track(rfs, &rtrack, fs->io);
 218
 219         init_resource_track(&rtrack, "fix_resize_inode", fs->io);
 220         retval = fix_resize_inode(rfs->new_fs);
 221         if (retval)
 222                 goto errout;
 223         print_resource_track(rfs, &rtrack, fs->io);
 224
 225         init_resource_track(&rtrack, "fix_sb_journal_backup", fs->io);
 226         retval = fix_sb_journal_backup(rfs->new_fs);
 227         if (retval)
 228                 goto errout;
 229         print_resource_track(rfs, &rtrack, fs->io);
 230
 231         retval = ext2fs_set_gdt_csum(rfs->new_fs);
 232         if (retval)
 233                 goto errout;
 234
 235         rfs->new_fs->super->s_state &= ~EXT2_ERROR_FS;
 236         rfs->new_fs->flags &= ~EXT2_FLAG_MASTER_SB_ONLY;
 237
 238         print_resource_track(rfs, &overall_track, fs->io);
 239         retval = ext2fs_close_free(&rfs->new_fs);
 240         if (retval)
 241                 goto errout;
 242
 243         rfs->flags = flags;
 244
 245         ext2fs_free(rfs->old_fs);
 246         rfs->old_fs = NULL;
 247         if (rfs->itable_buf)
 248                 ext2fs_free_mem(&rfs->itable_buf);
 249         if (rfs->reserve_blocks)
 250                 ext2fs_free_block_bitmap(rfs->reserve_blocks);
 251         if (rfs->move_blocks)
 252                 ext2fs_free_block_bitmap(rfs->move_blocks);
 253         ext2fs_free_mem(&rfs);
 254
 255         return 0;
 256
 257 errout:
 258         if (rfs->new_fs) {
 259                 ext2fs_free(rfs->new_fs);
 260                 rfs->new_fs = NULL;
 261         }
 262         if (rfs->itable_buf)
 263                 ext2fs_free_mem(&rfs->itable_buf);
 264         ext2fs_free_mem(&rfs);
 265         return retval;
 266 }
 267
 268 /* Keep the size of the group descriptor region constant */
 269 static void adjust_reserved_gdt_blocks(ext2_filsys old_fs, ext2_filsys fs)
 270 {
 271         if (ext2fs_has_feature_resize_inode(fs->super) &&
 272             (old_fs->desc_blocks != fs->desc_blocks)) {
 273                 int new;
 274
 275                 new = ((int) fs->super->s_reserved_gdt_blocks) +
 276                         (old_fs->desc_blocks - fs->desc_blocks);
 277                 if (new < 0)
 278                         new = 0;
 279                 if (new > (int) fs->blocksize/4)
 280                         new = fs->blocksize/4;
 281                 fs->super->s_reserved_gdt_blocks = new;
 282         }
 283 }
 284
 285 /* Toggle 64bit mode */
 286 static errcode_t resize_group_descriptors(ext2_resize_t rfs, blk64_t new_size)
 287 {
 288         void *o, *n, *new_group_desc;
 289         dgrp_t i;
 290         int copy_size;
 291         errcode_t retval;
 292
 293         if (!(rfs->flags & (RESIZE_DISABLE_64BIT | RESIZE_ENABLE_64BIT)))
 294                 return 0;
 295
 296         if (new_size != ext2fs_blocks_count(rfs->new_fs->super) ||
 297             ext2fs_blocks_count(rfs->new_fs->super) >= (1ULL << 32) ||
 298             (rfs->flags & RESIZE_DISABLE_64BIT &&
 299              rfs->flags & RESIZE_ENABLE_64BIT))
 300                 return EXT2_ET_INVALID_ARGUMENT;
 301
 302         if (rfs->flags & RESIZE_DISABLE_64BIT) {
 303                 ext2fs_clear_feature_64bit(rfs->new_fs->super);
 304                 rfs->new_fs->super->s_desc_size = EXT2_MIN_DESC_SIZE;
 305         } else if (rfs->flags & RESIZE_ENABLE_64BIT) {
 306                 ext2fs_set_feature_64bit(rfs->new_fs->super);
 307                 rfs->new_fs->super->s_desc_size = EXT2_MIN_DESC_SIZE_64BIT;
 308         }
 309
 310         if (EXT2_DESC_SIZE(rfs->old_fs->super) ==
 311             EXT2_DESC_SIZE(rfs->new_fs->super))
 312                 return 0;
 313
 314         o = rfs->new_fs->group_desc;
 315         rfs->new_fs->desc_blocks = ext2fs_div_ceil(
 316                         rfs->old_fs->group_desc_count,
 317                         EXT2_DESC_PER_BLOCK(rfs->new_fs->super));
 318         retval = ext2fs_get_arrayzero(rfs->new_fs->desc_blocks,
 319                                       rfs->old_fs->blocksize, &new_group_desc);
 320         if (retval)
 321                 return retval;
 322
 323         n = new_group_desc;
 324
 325         if (EXT2_DESC_SIZE(rfs->old_fs->super) <=
 326             EXT2_DESC_SIZE(rfs->new_fs->super))
 327                 copy_size = EXT2_DESC_SIZE(rfs->old_fs->super);
 328         else
 329                 copy_size = EXT2_DESC_SIZE(rfs->new_fs->super);
 330         for (i = 0; i < rfs->old_fs->group_desc_count; i++) {
 331                 memcpy(n, o, copy_size);
 332                 n = (char *)n + EXT2_DESC_SIZE(rfs->new_fs->super);
 333                 o = (char *)o + EXT2_DESC_SIZE(rfs->old_fs->super);
 334         }
 335
 336         ext2fs_free_mem(&rfs->new_fs->group_desc);
 337         rfs->new_fs->group_desc = new_group_desc;
 338
 339         for (i = 0; i < rfs->old_fs->group_desc_count; i++)
 340                 ext2fs_group_desc_csum_set(rfs->new_fs, i);
 341
 342         adjust_reserved_gdt_blocks(rfs->old_fs, rfs->new_fs);
 343
 344         return 0;
 345 }
 346
 347 /* Move bitmaps/inode tables out of the way. */
 348 static errcode_t move_bg_metadata(ext2_resize_t rfs)
 349 {
 350         dgrp_t i;
 351         blk64_t b, c, d, old_desc_blocks, new_desc_blocks, j;
 352         ext2fs_block_bitmap old_map, new_map;
 353         int old, new;
 354         errcode_t retval;
 355         int cluster_ratio;
 356
 357         if (!(rfs->flags & (RESIZE_DISABLE_64BIT | RESIZE_ENABLE_64BIT)))
 358                 return 0;
 359
 360         retval = ext2fs_allocate_block_bitmap(rfs->old_fs, "oldfs", &old_map);
 361         if (retval)
 362                 return retval;
 363
 364         retval = ext2fs_allocate_block_bitmap(rfs->new_fs, "newfs", &new_map);
 365         if (retval)
 366                 goto out;
 367
 368         if (ext2fs_has_feature_meta_bg(rfs->old_fs->super)) {
 369                 old_desc_blocks = rfs->old_fs->super->s_first_meta_bg;
 370                 new_desc_blocks = rfs->new_fs->super->s_first_meta_bg;
 371         } else {
 372                 old_desc_blocks = rfs->old_fs->desc_blocks +
 373                                 rfs->old_fs->super->s_reserved_gdt_blocks;
 374                 new_desc_blocks = rfs->new_fs->desc_blocks +
 375                                 rfs->new_fs->super->s_reserved_gdt_blocks;
 376         }
 377
 378         /* Construct bitmaps of super/descriptor blocks in old and new fs */
 379         for (i = 0; i < rfs->old_fs->group_desc_count; i++) {
 380                 retval = ext2fs_super_and_bgd_loc2(rfs->old_fs, i, &b, &c, &d,
 381                                                    NULL);
 382                 if (retval)
 383                         goto out;
 384                 if (b)
 385                         ext2fs_mark_block_bitmap2(old_map, b);
 386                 for (j = 0; c != 0 && j < old_desc_blocks; j++)
 387                         ext2fs_mark_block_bitmap2(old_map, c + j);
 388                 if (d)
 389                         ext2fs_mark_block_bitmap2(old_map, d);
 390
 391                 retval = ext2fs_super_and_bgd_loc2(rfs->new_fs, i, &b, &c, &d,
 392                                                    NULL);
 393                 if (retval)
 394                         goto out;
 395                 if (b)
 396                         ext2fs_mark_block_bitmap2(new_map, b);
 397                 for (j = 0; c != 0 && j < new_desc_blocks; j++)
 398                         ext2fs_mark_block_bitmap2(new_map, c + j);
 399                 if (d)
 400                         ext2fs_mark_block_bitmap2(new_map, d);
 401         }
 402
 403         cluster_ratio = EXT2FS_CLUSTER_RATIO(rfs->new_fs);
 404
 405         /* Find changes in block allocations for bg metadata */
 406         for (b = EXT2FS_B2C(rfs->old_fs,
 407                             rfs->old_fs->super->s_first_data_block);
 408              b < ext2fs_blocks_count(rfs->new_fs->super);
 409              b += cluster_ratio) {
 410                 old = ext2fs_test_block_bitmap2(old_map, b);
 411                 new = ext2fs_test_block_bitmap2(new_map, b);
 412
 413                 if (old && !new) {
 414                         /* mark old_map, unmark new_map */
 415                         if (cluster_ratio == 1)
 416                                 ext2fs_unmark_block_bitmap2(
 417                                                 rfs->new_fs->block_map, b);
 418                 } else if (!old && new)
 419                         ; /* unmark old_map, mark new_map */
 420                 else {
 421                         ext2fs_unmark_block_bitmap2(old_map, b);
 422                         ext2fs_unmark_block_bitmap2(new_map, b);
 423                 }
 424         }
 425
 426         /*
 427          * new_map now shows blocks that have been newly allocated.
 428          * old_map now shows blocks that have been newly freed.
 429          */
 430
 431         /*
 432          * Move any conflicting bitmaps and inode tables.  Ensure that we
 433          * don't try to free clusters associated with bitmaps or tables.
 434          */
 435         for (i = 0; i < rfs->old_fs->group_desc_count; i++) {
 436                 b = ext2fs_block_bitmap_loc(rfs->new_fs, i);
 437                 if (ext2fs_test_block_bitmap2(new_map, b))
 438                         ext2fs_block_bitmap_loc_set(rfs->new_fs, i, 0);
 439                 else if (ext2fs_test_block_bitmap2(old_map, b))
 440                         ext2fs_unmark_block_bitmap2(old_map, b);
 441
 442                 b = ext2fs_inode_bitmap_loc(rfs->new_fs, i);
 443                 if (ext2fs_test_block_bitmap2(new_map, b))
 444                         ext2fs_inode_bitmap_loc_set(rfs->new_fs, i, 0);
 445                 else if (ext2fs_test_block_bitmap2(old_map, b))
 446                         ext2fs_unmark_block_bitmap2(old_map, b);
 447
 448                 c = ext2fs_inode_table_loc(rfs->new_fs, i);
 449                 for (b = 0;
 450                      b < rfs->new_fs->inode_blocks_per_group;
 451                      b++) {
 452                         if (ext2fs_test_block_bitmap2(new_map, b + c))
 453                                 ext2fs_inode_table_loc_set(rfs->new_fs, i, 0);
 454                         else if (ext2fs_test_block_bitmap2(old_map, b + c))
 455                                 ext2fs_unmark_block_bitmap2(old_map, b + c);
 456                 }
 457         }
 458
 459         /* Free unused clusters */
 460         for (b = 0;
 461              cluster_ratio > 1 && b < ext2fs_blocks_count(rfs->new_fs->super);
 462              b += cluster_ratio)
 463                 if (ext2fs_test_block_bitmap2(old_map, b))
 464                         ext2fs_unmark_block_bitmap2(rfs->new_fs->block_map, b);
 465 out:
 466         if (old_map)
 467                 ext2fs_free_block_bitmap(old_map);
 468         if (new_map)
 469                 ext2fs_free_block_bitmap(new_map);
 470         return retval;
 471 }
 472
 473 /* Zero out the high bits of extent fields */
 474 static errcode_t zero_high_bits_in_extents(ext2_filsys fs, ext2_ino_t ino,
 475                                  struct ext2_inode *inode)
 476 {
 477         ext2_extent_handle_t    handle;
 478         struct ext2fs_extent    extent;
 479         int                     op = EXT2_EXTENT_ROOT;
 480         errcode_t               errcode;
 481
 482         if (!(inode->i_flags & EXT4_EXTENTS_FL))
 483                 return 0;
 484
 485         errcode = ext2fs_extent_open(fs, ino, &handle);
 486         if (errcode)
 487                 return errcode;
 488
 489         while (1) {
 490                 errcode = ext2fs_extent_get(handle, op, &extent);
 491                 if (errcode)
 492                         break;
 493
 494                 op = EXT2_EXTENT_NEXT_SIB;
 495
 496                 if (extent.e_pblk > (1ULL << 32)) {
 497                         extent.e_pblk &= (1ULL << 32) - 1;
 498                         errcode = ext2fs_extent_replace(handle, 0, &extent);
 499                         if (errcode)
 500                                 break;
 501                 }
 502         }
 503
 504         /* Ok if we run off the end */
 505         if (errcode == EXT2_ET_EXTENT_NO_NEXT)
 506                 errcode = 0;
 507         ext2fs_extent_free(handle);
 508         return errcode;
 509 }
 510
 511 /* Zero out the high bits of inodes. */
 512 static errcode_t zero_high_bits_in_inodes(ext2_resize_t rfs)
 513 {
 514         ext2_filsys     fs = rfs->old_fs;
 515         int length = EXT2_INODE_SIZE(fs->super);
 516         struct ext2_inode *inode = NULL;
 517         ext2_inode_scan scan = NULL;
 518         errcode_t       retval;
 519         ext2_ino_t      ino;
 520
 521         if (!(rfs->flags & (RESIZE_DISABLE_64BIT | RESIZE_ENABLE_64BIT)))
 522                 return 0;
 523
 524         if (fs->super->s_creator_os == EXT2_OS_HURD)
 525                 return 0;
 526
 527         retval = ext2fs_open_inode_scan(fs, 0, &scan);
 528         if (retval)
 529                 return retval;
 530
 531         retval = ext2fs_get_mem(length, &inode);
 532         if (retval)
 533                 goto out;
 534
 535         do {
 536                 retval = ext2fs_get_next_inode_full(scan, &ino, inode, length);
 537                 if (retval)
 538                         goto out;
 539                 if (!ino)
 540                         break;
 541                 if (!ext2fs_test_inode_bitmap2(fs->inode_map, ino))
 542                         continue;
 543
 544                 /*
 545                  * Here's how we deal with high block number fields:
 546                  *
 547                  *  - i_size_high has been been written out with i_size_lo
 548                  *    since the ext2 days, so no conversion is needed.
 549                  *
 550                  *  - i_blocks_hi is guarded by both the huge_file feature and
 551                  *    inode flags and has always been written out with
 552                  *    i_blocks_lo if the feature is set.  The field is only
 553                  *    ever read if both feature and inode flag are set, so
 554                  *    we don't need to zero it now.
 555                  *
 556                  *  - i_file_acl_high can be uninitialized, so zero it if
 557                  *    it isn't already.
 558                  */
 559                 if (inode->osd2.linux2.l_i_file_acl_high) {
 560                         inode->osd2.linux2.l_i_file_acl_high = 0;
 561                         retval = ext2fs_write_inode_full(fs, ino, inode,
 562                                                          length);
 563                         if (retval)
 564                                 goto out;
 565                 }
 566
 567                 retval = zero_high_bits_in_extents(fs, ino, inode);
 568                 if (retval)
 569                         goto out;
 570         } while (ino);
 571
 572 out:
 573         if (inode)
 574                 ext2fs_free_mem(&inode);
 575         if (scan)
 576                 ext2fs_close_inode_scan(scan);
 577         return retval;
 578 }
 579
 580 /*
 581  * Clean up the bitmaps for uninitialized bitmaps
 582  */
 583 static void fix_uninit_block_bitmaps(ext2_filsys fs)
 584 {
 585         blk64_t         blk, lblk;
 586         dgrp_t          g;
 587         unsigned int    i;
 588
 589         if (!ext2fs_has_group_desc_csum(fs))
 590                 return;
 591
 592         for (g=0; g < fs->group_desc_count; g++) {
 593                 if (!(ext2fs_bg_flags_test(fs, g, EXT2_BG_BLOCK_UNINIT)))
 594                         continue;
 595
 596                 blk = ext2fs_group_first_block2(fs, g);
 597                 lblk = ext2fs_group_last_block2(fs, g);
 598                 ext2fs_unmark_block_bitmap_range2(fs->block_map, blk,
 599                                                   lblk - blk + 1);
 600
 601                 ext2fs_reserve_super_and_bgd(fs, g, fs->block_map);
 602                 ext2fs_mark_block_bitmap2(fs->block_map,
 603                                           ext2fs_block_bitmap_loc(fs, g));
 604                 ext2fs_mark_block_bitmap2(fs->block_map,
 605                                           ext2fs_inode_bitmap_loc(fs, g));
 606                 for (i = 0, blk = ext2fs_inode_table_loc(fs, g);
 607                      i < fs->inode_blocks_per_group;
 608                      i++, blk++)
 609                         ext2fs_mark_block_bitmap2(fs->block_map, blk);
 610         }
 611 }
 612
 613 /* --------------------------------------------------------------------
 614  *
 615  * Resize processing, phase 1.
 616  *
 617  * In this phase we adjust the in-memory superblock information, and
 618  * initialize any new parts of the inode table.  The new parts of the
 619  * inode table are created in virgin disk space, so we can abort here
 620  * without any side effects.
 621  * --------------------------------------------------------------------
 622  */
 623
 624 /*
 625  * If the group descriptor's bitmap and inode table blocks are valid,
 626  * release them in the new filesystem data structure, and mark them as
 627  * reserved so the old inode table blocks don't get overwritten.
 628  */
 629 static errcode_t free_gdp_blocks(ext2_filsys fs,
 630                                  ext2fs_block_bitmap reserve_blocks,
 631                                  ext2_filsys old_fs,
 632                                  dgrp_t group)
 633 {
 634         blk64_t         blk;
 635         unsigned int    j;
 636         dgrp_t          i;
 637         ext2fs_block_bitmap bg_map = NULL;
 638         errcode_t       retval = 0;
 639         dgrp_t          count = old_fs->group_desc_count - fs->group_desc_count;
 640
 641         /* If bigalloc, don't free metadata living in the same cluster */
 642         if (EXT2FS_CLUSTER_RATIO(fs) > 1) {
 643                 retval = ext2fs_allocate_block_bitmap(fs, "bgdata", &bg_map);
 644                 if (retval)
 645                         goto out;
 646
 647                 retval = mark_table_blocks(fs, bg_map);
 648                 if (retval)
 649                         goto out;
 650         }
 651
 652         for (i = group; i < group + count; i++) {
 653                 blk = ext2fs_block_bitmap_loc(old_fs, i);
 654                 if (blk &&
 655                     (blk < ext2fs_blocks_count(fs->super)) &&
 656                     !(bg_map && ext2fs_test_block_bitmap2(bg_map, blk))) {
 657                         ext2fs_block_alloc_stats2(fs, blk, -1);
 658                         ext2fs_mark_block_bitmap2(reserve_blocks, blk);
 659                 }
 660
 661                 blk = ext2fs_inode_bitmap_loc(old_fs, i);
 662                 if (blk &&
 663                     (blk < ext2fs_blocks_count(fs->super)) &&
 664                     !(bg_map && ext2fs_test_block_bitmap2(bg_map, blk))) {
 665                         ext2fs_block_alloc_stats2(fs, blk, -1);
 666                         ext2fs_mark_block_bitmap2(reserve_blocks, blk);
 667                 }
 668
 669                 blk = ext2fs_inode_table_loc(old_fs, i);
 670                 for (j = 0;
 671                      j < fs->inode_blocks_per_group; j++, blk++) {
 672                         if (blk >= ext2fs_blocks_count(fs->super) ||
 673                             (bg_map && ext2fs_test_block_bitmap2(bg_map, blk)))
 674                                 continue;
 675                         ext2fs_block_alloc_stats2(fs, blk, -1);
 676                         ext2fs_mark_block_bitmap2(reserve_blocks, blk);
 677                 }
 678         }
 679
 680 out:
 681         if (bg_map)
 682                 ext2fs_free_block_bitmap(bg_map);
 683         return retval;
 684 }
 685
 686 /*
 687  * This routine is shared by the online and offline resize routines.
 688  * All of the information which is adjusted in memory is done here.
 689  */
 690 errcode_t adjust_fs_info(ext2_filsys fs, ext2_filsys old_fs,
 691                          ext2fs_block_bitmap reserve_blocks, blk64_t new_size)
 692 {
 693         errcode_t       retval;
 694         blk64_t         overhead = 0;
 695         blk64_t         rem;
 696         blk64_t         blk, group_block;
 697         blk64_t         real_end;
 698         blk64_t         old_numblocks, numblocks, adjblocks;
 699         unsigned long   i, j, old_desc_blocks;
 700         unsigned int    meta_bg, meta_bg_size;
 701         int             has_super, csum_flag, has_bg;
 702         unsigned long long new_inodes;  /* u64 to check for overflow */
 703         double          percent;
 704
 705         ext2fs_blocks_count_set(fs->super, new_size);
 706
 707 retry:
 708         fs->group_desc_count = ext2fs_div64_ceil(ext2fs_blocks_count(fs->super) -
 709                                        fs->super->s_first_data_block,
 710                                        EXT2_BLOCKS_PER_GROUP(fs->super));
 711         if (fs->group_desc_count == 0)
 712                 return EXT2_ET_TOOSMALL;
 713         fs->desc_blocks = ext2fs_div_ceil(fs->group_desc_count,
 714                                           EXT2_DESC_PER_BLOCK(fs->super));
 715
 716         /*
 717          * Overhead is the number of bookkeeping blocks per group.  It
 718          * includes the superblock backup, the group descriptor
 719          * backups, the inode bitmap, the block bitmap, and the inode
 720          * table.
 721          */
 722         overhead = (int) (2 + fs->inode_blocks_per_group);
 723
 724         has_bg = 0;
 725         if (ext2fs_has_feature_sparse_super2(fs->super)) {
 726                 /*
 727                  * We have to do this manually since
 728                  * super->s_backup_bgs hasn't been set up yet.
 729                  */
 730                 if (fs->group_desc_count == 2)
 731                         has_bg = fs->super->s_backup_bgs[0] != 0;
 732                 else
 733                         has_bg = fs->super->s_backup_bgs[1] != 0;
 734         } else
 735                 has_bg = ext2fs_bg_has_super(fs, fs->group_desc_count - 1);
 736         if (has_bg)
 737                 overhead += 1 + fs->desc_blocks +
 738                         fs->super->s_reserved_gdt_blocks;
 739
 740         /*
 741          * See if the last group is big enough to support the
 742          * necessary data structures.  If not, we need to get rid of
 743          * it.
 744          */
 745         rem = (ext2fs_blocks_count(fs->super) - fs->super->s_first_data_block) %
 746                 fs->super->s_blocks_per_group;
 747         if ((fs->group_desc_count == 1) && rem && (rem < overhead))
 748                 return EXT2_ET_TOOSMALL;
 749         if ((fs->group_desc_count > 1) && rem && (rem < overhead+50)) {
 750                 ext2fs_blocks_count_set(fs->super,
 751                                         ext2fs_blocks_count(fs->super) - rem);
 752                 goto retry;
 753         }
 754         /*
 755          * Adjust the number of inodes
 756          */
 757         new_inodes =(unsigned long long) fs->super->s_inodes_per_group * fs->group_desc_count;
 758         if (new_inodes > ~0U) {
 759                 fprintf(stderr, _("inodes (%llu) must be less than %u\n"),
 760                                    new_inodes, ~0U);
 761                 return EXT2_ET_TOO_MANY_INODES;
 762         }
 763         fs->super->s_inodes_count = fs->super->s_inodes_per_group *
 764                 fs->group_desc_count;
 765
 766         /*
 767          * Adjust the number of free blocks
 768          */
 769         blk = ext2fs_blocks_count(old_fs->super);
 770         if (blk > ext2fs_blocks_count(fs->super))
 771                 ext2fs_free_blocks_count_set(fs->super,
 772                         ext2fs_free_blocks_count(fs->super) -
 773                         (blk - ext2fs_blocks_count(fs->super)));
 774         else
 775                 ext2fs_free_blocks_count_set(fs->super,
 776                         ext2fs_free_blocks_count(fs->super) +
 777                         (ext2fs_blocks_count(fs->super) - blk));
 778
 779         /*
 780          * Adjust the number of reserved blocks
 781          */
 782         percent = (ext2fs_r_blocks_count(old_fs->super) * 100.0) /
 783                 ext2fs_blocks_count(old_fs->super);
 784         ext2fs_r_blocks_count_set(fs->super,
 785                                   (percent * ext2fs_blocks_count(fs->super) /
 786                                    100.0));
 787
 788         /*
 789          * Adjust the bitmaps for size
 790          */
 791         retval = ext2fs_resize_inode_bitmap2(fs->super->s_inodes_count,
 792                                             fs->super->s_inodes_count,
 793                                             fs->inode_map);
 794         if (retval) goto errout;
 795
 796         real_end = EXT2_GROUPS_TO_BLOCKS(fs->super, fs->group_desc_count) - 1 +
 797                 fs->super->s_first_data_block;
 798         retval = ext2fs_resize_block_bitmap2(new_size - 1,
 799                                              real_end, fs->block_map);
 800         if (retval) goto errout;
 801
 802         /*
 803          * If we are growing the file system, also grow the size of
 804          * the reserve_blocks bitmap
 805          */
 806         if (reserve_blocks && new_size > ext2fs_blocks_count(old_fs->super)) {
 807                 retval = ext2fs_resize_block_bitmap2(new_size - 1,
 808                                                      real_end, reserve_blocks);
 809                 if (retval) goto errout;
 810         }
 811
 812         /*
 813          * Reallocate the group descriptors as necessary.
 814          */
 815         if (EXT2_DESC_SIZE(old_fs->super) == EXT2_DESC_SIZE(fs->super) &&
 816             old_fs->desc_blocks != fs->desc_blocks) {
 817                 retval = ext2fs_resize_mem(old_fs->desc_blocks *
 818                                            fs->blocksize,
 819                                            fs->desc_blocks * fs->blocksize,
 820                                            &fs->group_desc);
 821                 if (retval)
 822                         goto errout;
 823                 if (fs->desc_blocks > old_fs->desc_blocks)
 824                         memset((char *) fs->group_desc +
 825                                (old_fs->desc_blocks * fs->blocksize), 0,
 826                                (fs->desc_blocks - old_fs->desc_blocks) *
 827                                fs->blocksize);
 828         }
 829
 830         /*
 831          * If the resize_inode feature is set, and we are changing the
 832          * number of descriptor blocks, then adjust
 833          * s_reserved_gdt_blocks if possible to avoid needing to move
 834          * the inode table either now or in the future.
 835          *
 836          * Note: If we're converting to 64bit mode, we did this earlier.
 837          */
 838         if (EXT2_DESC_SIZE(old_fs->super) == EXT2_DESC_SIZE(fs->super))
 839                 adjust_reserved_gdt_blocks(old_fs, fs);
 840
 841         if (ext2fs_has_feature_meta_bg(fs->super) &&
 842             (fs->super->s_first_meta_bg > fs->desc_blocks)) {
 843                 ext2fs_clear_feature_meta_bg(fs->super);
 844                 fs->super->s_first_meta_bg = 0;
 845         }
 846
 847         /*
 848          * Update the location of the backup superblocks if the
 849          * sparse_super2 feature is enabled.
 850          */
 851         if (ext2fs_has_feature_sparse_super2(fs->super)) {
 852                 dgrp_t last_bg = fs->group_desc_count - 1;
 853                 dgrp_t old_last_bg = old_fs->group_desc_count - 1;
 854
 855                 if (last_bg > old_last_bg) {
 856                         if (old_fs->group_desc_count == 1)
 857                                 fs->super->s_backup_bgs[0] = 1;
 858                         if ((old_fs->group_desc_count < 3 &&
 859                              fs->group_desc_count > 2) ||
 860                             fs->super->s_backup_bgs[1])
 861                                 fs->super->s_backup_bgs[1] = last_bg;
 862                 } else if (last_bg < old_last_bg) {
 863                         if (fs->super->s_backup_bgs[0] > last_bg)
 864                                 fs->super->s_backup_bgs[0] = 0;
 865                         if (fs->super->s_backup_bgs[1] > last_bg)
 866                                 fs->super->s_backup_bgs[1] = 0;
 867                         if (last_bg > 1 &&
 868                             old_fs->super->s_backup_bgs[1] == old_last_bg)
 869                                 fs->super->s_backup_bgs[1] = last_bg;
 870                 }
 871         }
 872
 873         /*
 874          * If we are shrinking the number of block groups, we're done
 875          * and can exit now.
 876          */
 877         if (old_fs->group_desc_count > fs->group_desc_count) {
 878                 /*
 879                  * Check the block groups that we are chopping off
 880                  * and free any blocks associated with their metadata
 881                  */
 882                 retval = free_gdp_blocks(fs, reserve_blocks, old_fs,
 883                                          fs->group_desc_count);
 884                 goto errout;
 885         }
 886
 887         /*
 888          * Fix the count of the last (old) block group
 889          */
 890         old_numblocks = (ext2fs_blocks_count(old_fs->super) -
 891                          old_fs->super->s_first_data_block) %
 892                                  old_fs->super->s_blocks_per_group;
 893         if (!old_numblocks)
 894                 old_numblocks = old_fs->super->s_blocks_per_group;
 895         if (old_fs->group_desc_count == fs->group_desc_count) {
 896                 numblocks = (ext2fs_blocks_count(fs->super) -
 897                              fs->super->s_first_data_block) %
 898                         fs->super->s_blocks_per_group;
 899                 if (!numblocks)
 900                         numblocks = fs->super->s_blocks_per_group;
 901         } else
 902                 numblocks = fs->super->s_blocks_per_group;
 903         i = old_fs->group_desc_count - 1;
 904         ext2fs_bg_free_blocks_count_set(fs, i, ext2fs_bg_free_blocks_count(fs, i) + (numblocks - old_numblocks));
 905         ext2fs_group_desc_csum_set(fs, i);
 906
 907         /*
 908          * If the number of block groups is staying the same, we're
 909          * done and can exit now.  (If the number block groups is
 910          * shrinking, we had exited earlier.)
 911          */
 912         if (old_fs->group_desc_count >= fs->group_desc_count) {
 913                 retval = 0;
 914                 goto errout;
 915         }
 916
 917         /*
 918          * Initialize the new block group descriptors
 919          */
 920         group_block = ext2fs_group_first_block2(fs,
 921                                                 old_fs->group_desc_count);
 922         csum_flag = ext2fs_has_group_desc_csum(fs);
 923         if (getenv("RESIZE2FS_FORCE_LAZY_ITABLE_INIT") ||
 924             (!getenv("RESIZE2FS_FORCE_ITABLE_INIT") &&
 925              access("/sys/fs/ext4/features/lazy_itable_init", F_OK) == 0))
 926                 lazy_itable_init = 1;
 927         if (ext2fs_has_feature_meta_bg(fs->super))
 928                 old_desc_blocks = fs->super->s_first_meta_bg;
 929         else
 930                 old_desc_blocks = fs->desc_blocks +
 931                         fs->super->s_reserved_gdt_blocks;
 932
 933         /*
 934          * If we changed the number of block_group descriptor blocks,
 935          * we need to make sure they are all marked as reserved in the
 936          * filesystem's block allocation map.
 937          */
 938         for (i = 0; i < old_fs->group_desc_count; i++)
 939                 ext2fs_reserve_super_and_bgd(fs, i, fs->block_map);
 940
 941         for (i = old_fs->group_desc_count;
 942              i < fs->group_desc_count; i++) {
 943                 memset(ext2fs_group_desc(fs, fs->group_desc, i), 0,
 944                        sizeof(struct ext2_group_desc));
 945                 adjblocks = 0;
 946
 947                 ext2fs_bg_flags_zap(fs, i);
 948                 if (csum_flag) {
 949                         ext2fs_bg_flags_set(fs, i, EXT2_BG_INODE_UNINIT);
 950                         if (!lazy_itable_init)
 951                                 ext2fs_bg_flags_set(fs, i,
 952                                                     EXT2_BG_INODE_ZEROED);
 953                         ext2fs_bg_itable_unused_set(fs, i,
 954                                         fs->super->s_inodes_per_group);
 955                 }
 956
 957                 numblocks = ext2fs_group_blocks_count(fs, i);
 958                 if ((i < fs->group_desc_count - 1) && csum_flag)
 959                         ext2fs_bg_flags_set(fs, i, EXT2_BG_BLOCK_UNINIT);
 960
 961                 has_super = ext2fs_bg_has_super(fs, i);
 962                 if (has_super) {
 963                         ext2fs_block_alloc_stats2(fs, group_block, +1);
 964                         adjblocks++;
 965                 }
 966                 meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
 967                 meta_bg = i / meta_bg_size;
 968                 if (!ext2fs_has_feature_meta_bg(fs->super) ||
 969                     (meta_bg < fs->super->s_first_meta_bg)) {
 970                         if (has_super) {
 971                                 for (j=0; j < old_desc_blocks; j++)
 972                                         ext2fs_block_alloc_stats2(fs,
 973                                                  group_block + 1 + j, +1);
 974                                 adjblocks += old_desc_blocks;
 975                         }
 976                 } else {
 977                         if (has_super)
 978                                 has_super = 1;
 979                         if (((i % meta_bg_size) == 0) ||
 980                             ((i % meta_bg_size) == 1) ||
 981                             ((i % meta_bg_size) == (meta_bg_size-1)))
 982                                 ext2fs_block_alloc_stats2(fs,
 983                                                  group_block + has_super, +1);
 984                 }
 985
 986                 adjblocks += 2 + fs->inode_blocks_per_group;
 987
 988                 numblocks -= adjblocks;
 989                 ext2fs_free_blocks_count_set(fs->super,
 990                              ext2fs_free_blocks_count(fs->super) - adjblocks);
 991                 fs->super->s_free_inodes_count +=
 992                         fs->super->s_inodes_per_group;
 993                 ext2fs_bg_free_blocks_count_set(fs, i, numblocks);
 994                 ext2fs_bg_free_inodes_count_set(fs, i,
 995                                                 fs->super->s_inodes_per_group);
 996                 ext2fs_bg_used_dirs_count_set(fs, i, 0);
 997                 ext2fs_group_desc_csum_set(fs, i);
 998
 999                 retval = ext2fs_allocate_group_table(fs, i, 0);
1000                 if (retval) goto errout;
1001
1002                 group_block += fs->super->s_blocks_per_group;
1003         }
1004         retval = 0;
1005
1006         /*
1007          * Mark all of the metadata blocks as reserved so they won't
1008          * get allocated by the call to ext2fs_allocate_group_table()
1009          * in blocks_to_move(), where we allocate new blocks to
1010          * replace those allocation bitmap and inode table blocks
1011          * which have to get relocated to make space for an increased
1012          * number of the block group descriptors.
1013          */
1014         if (reserve_blocks)
1015                 mark_table_blocks(fs, reserve_blocks);
1016
1017 errout:
1018         return (retval);
1019 }
1020
1021 /*
1022  * This routine adjusts the superblock and other data structures, both
1023  * in disk as well as in memory...
1024  */
1025 static errcode_t adjust_superblock(ext2_resize_t rfs, blk64_t new_size)
1026 {
1027         ext2_filsys     fs = rfs->new_fs;
1028         int             adj = 0;
1029         errcode_t       retval;
1030         blk64_t         group_block;
1031         unsigned long   i;
1032         unsigned long   max_group;
1033
1034         ext2fs_mark_super_dirty(fs);
1035         ext2fs_mark_bb_dirty(fs);
1036         ext2fs_mark_ib_dirty(fs);
1037
1038         retval = ext2fs_allocate_block_bitmap(fs, _("reserved blocks"),
1039                                               &rfs->reserve_blocks);
1040         if (retval)
1041                 return retval;
1042
1043         retval = adjust_fs_info(fs, rfs->old_fs, rfs->reserve_blocks, new_size);
1044         if (retval)
1045                 goto errout;
1046
1047         /*
1048          * Check to make sure there are enough inodes
1049          */
1050         if ((rfs->old_fs->super->s_inodes_count -
1051              rfs->old_fs->super->s_free_inodes_count) >
1052             rfs->new_fs->super->s_inodes_count) {
1053                 retval = ENOSPC;
1054                 goto errout;
1055         }
1056
1057         /*
1058          * If we are shrinking the number block groups, we're done and
1059          * can exit now.
1060          */
1061         if (rfs->old_fs->group_desc_count > fs->group_desc_count) {
1062                 retval = 0;
1063                 goto errout;
1064         }
1065
1066         /*
1067          * If the number of block groups is staying the same, we're
1068          * done and can exit now.  (If the number block groups is
1069          * shrinking, we had exited earlier.)
1070          */
1071         if (rfs->old_fs->group_desc_count >= fs->group_desc_count) {
1072                 retval = 0;
1073                 goto errout;
1074         }
1075
1076         /*
1077          * If we are using uninit_bg (aka GDT_CSUM) and the kernel
1078          * supports lazy inode initialization, we can skip
1079          * initializing the inode table.
1080          */
1081         if (lazy_itable_init && ext2fs_has_group_desc_csum(fs)) {
1082                 retval = 0;
1083                 goto errout;
1084         }
1085
1086         /*
1087          * Initialize the inode table
1088          */
1089         retval = ext2fs_get_array(fs->blocksize, fs->inode_blocks_per_group,
1090                                 &rfs->itable_buf);
1091         if (retval)
1092                 goto errout;
1093
1094         memset(rfs->itable_buf, 0, fs->blocksize * fs->inode_blocks_per_group);
1095         group_block = ext2fs_group_first_block2(fs,
1096                                                 rfs->old_fs->group_desc_count);
1097         adj = rfs->old_fs->group_desc_count;
1098         max_group = fs->group_desc_count - adj;
1099         if (rfs->progress) {
1100                 retval = rfs->progress(rfs, E2_RSZ_EXTEND_ITABLE_PASS,
1101                                        0, max_group);
1102                 if (retval)
1103                         goto errout;
1104         }
1105         for (i = rfs->old_fs->group_desc_count;
1106              i < fs->group_desc_count; i++) {
1107                 /*
1108                  * Write out the new inode table
1109                  */
1110                 retval = ext2fs_zero_blocks2(fs, ext2fs_inode_table_loc(fs, i),
1111                                              fs->inode_blocks_per_group, NULL,
1112                                              NULL);
1113                 if (retval)
1114                         goto errout;
1115
1116                 io_channel_flush(fs->io);
1117                 if (rfs->progress) {
1118                         retval = rfs->progress(rfs, E2_RSZ_EXTEND_ITABLE_PASS,
1119                                                i - adj + 1, max_group);
1120                         if (retval)
1121                                 goto errout;
1122                 }
1123                 group_block += fs->super->s_blocks_per_group;
1124         }
1125         io_channel_flush(fs->io);
1126         retval = 0;
1127
1128 errout:
1129         return retval;
1130 }
1131
1132 /* --------------------------------------------------------------------
1133  *
1134  * Resize processing, phase 2.
1135  *
1136  * In this phase we adjust determine which blocks need to be moved, in
1137  * blocks_to_move().  We then copy the blocks to their ultimate new
1138  * destinations using block_mover().  Since we are copying blocks to
1139  * their new locations, again during this pass we can abort without
1140  * any problems.
1141  * --------------------------------------------------------------------
1142  */
1143
1144 /*
1145  * This helper function creates a block bitmap with all of the
1146  * filesystem meta-data blocks.
1147  */
1148 static errcode_t mark_table_blocks(ext2_filsys fs,
1149                                    ext2fs_block_bitmap bmap)
1150 {
1151         dgrp_t                  i;
1152         blk64_t                 blk;
1153
1154         for (i = 0; i < fs->group_desc_count; i++) {
1155                 ext2fs_reserve_super_and_bgd(fs, i, bmap);
1156
1157                 /*
1158                  * Mark the blocks used for the inode table
1159                  */
1160                 blk = ext2fs_inode_table_loc(fs, i);
1161                 if (blk)
1162                         ext2fs_mark_block_bitmap_range2(bmap, blk,
1163                                                 fs->inode_blocks_per_group);
1164
1165                 /*
1166                  * Mark block used for the block bitmap
1167                  */
1168                 blk = ext2fs_block_bitmap_loc(fs, i);
1169                 if (blk)
1170                         ext2fs_mark_block_bitmap2(bmap, blk);
1171
1172                 /*
1173                  * Mark block used for the inode bitmap
1174                  */
1175                 blk = ext2fs_inode_bitmap_loc(fs, i);
1176                 if (blk)
1177                         ext2fs_mark_block_bitmap2(bmap, blk);
1178         }
1179         return 0;
1180 }
1181
1182 /*
1183  * This function checks to see if a particular block (either a
1184  * superblock or a block group descriptor) overlaps with an inode or
1185  * block bitmap block, or with the inode table.
1186  */
1187 static void mark_fs_metablock(ext2_resize_t rfs,
1188                               ext2fs_block_bitmap meta_bmap,
1189                               int group, blk64_t blk)
1190 {
1191         ext2_filsys fs = rfs->new_fs;
1192
1193         ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
1194         ext2fs_block_alloc_stats2(fs, blk, +1);
1195
1196         /*
1197          * Check to see if we overlap with the inode or block bitmap,
1198          * or the inode tables.  If not, and the block is in use, then
1199          * mark it as a block to be moved.
1200          */
1201         if (is_block_bm(fs, group, blk)) {
1202                 ext2fs_block_bitmap_loc_set(fs, group, 0);
1203                 rfs->needed_blocks++;
1204                 return;
1205         }
1206         if (is_inode_bm(fs, group, blk)) {
1207                 ext2fs_inode_bitmap_loc_set(fs, group, 0);
1208                 rfs->needed_blocks++;
1209                 return;
1210         }
1211         if (is_inode_tb(fs, group, blk)) {
1212                 ext2fs_inode_table_loc_set(fs, group, 0);
1213                 rfs->needed_blocks++;
1214                 return;
1215         }
1216         if (ext2fs_has_feature_flex_bg(fs->super)) {
1217                 dgrp_t i;
1218
1219                 for (i = 0; i < rfs->old_fs->group_desc_count; i++) {
1220                         if (is_block_bm(fs, i, blk)) {
1221                                 ext2fs_block_bitmap_loc_set(fs, i, 0);
1222                                 rfs->needed_blocks++;
1223                                 return;
1224                         }
1225                         if (is_inode_bm(fs, i, blk)) {
1226                                 ext2fs_inode_bitmap_loc_set(fs, i, 0);
1227                                 rfs->needed_blocks++;
1228                                 return;
1229                         }
1230                         if (is_inode_tb(fs, i, blk)) {
1231                                 ext2fs_inode_table_loc_set(fs, i, 0);
1232                                 rfs->needed_blocks++;
1233                                 return;
1234                         }
1235                 }
1236         }
1237
1238         if (ext2fs_has_group_desc_csum(fs) &&
1239             (ext2fs_bg_flags_test(fs, group, EXT2_BG_BLOCK_UNINIT))) {
1240                 /*
1241                  * If the block bitmap is uninitialized, which means
1242                  * nothing other than standard metadata in use.
1243                  */
1244                 return;
1245         } else if (ext2fs_test_block_bitmap2(rfs->old_fs->block_map, blk) &&
1246                    !ext2fs_test_block_bitmap2(meta_bmap, blk)) {
1247                 ext2fs_mark_block_bitmap2(rfs->move_blocks, blk);
1248                 rfs->needed_blocks++;
1249         }
1250 }
1251
1252
1253 /*
1254  * This routine marks and unmarks reserved blocks in the new block
1255  * bitmap.  It also determines which blocks need to be moved and
1256  * places this information into the move_blocks bitmap.
1257  */
1258 static errcode_t blocks_to_move(ext2_resize_t rfs)
1259 {
1260         unsigned int    j;
1261         int             has_super;
1262         dgrp_t          i, max_groups, g;
1263         blk64_t         blk, group_blk;
1264         blk64_t         old_blocks, new_blocks, group_end, cluster_freed;
1265         blk64_t         new_size;
1266         unsigned int    meta_bg, meta_bg_size;
1267         errcode_t       retval;
1268         ext2_filsys     fs, old_fs;
1269         ext2fs_block_bitmap     meta_bmap, new_meta_bmap = NULL;
1270         int             flex_bg;
1271
1272         fs = rfs->new_fs;
1273         old_fs = rfs->old_fs;
1274         if (ext2fs_blocks_count(old_fs->super) > ext2fs_blocks_count(fs->super))
1275                 fs = rfs->old_fs;
1276
1277         retval = ext2fs_allocate_block_bitmap(fs, _("blocks to be moved"),
1278                                               &rfs->move_blocks);
1279         if (retval)
1280                 return retval;
1281
1282         retval = ext2fs_allocate_block_bitmap(fs, _("meta-data blocks"),
1283                                               &meta_bmap);
1284         if (retval)
1285                 return retval;
1286
1287         retval = mark_table_blocks(old_fs, meta_bmap);
1288         if (retval)
1289                 return retval;
1290
1291         fs = rfs->new_fs;
1292
1293         /*
1294          * If we're shrinking the filesystem, we need to move any
1295          * group's metadata blocks (either allocation bitmaps or the
1296          * inode table) which are beyond the end of the new
1297          * filesystem.
1298          */
1299         new_size = ext2fs_blocks_count(fs->super);
1300         if (new_size < ext2fs_blocks_count(old_fs->super)) {
1301                 for (g = 0; g < fs->group_desc_count; g++) {
1302                         int realloc = 0;
1303                         /*
1304                          * ext2fs_allocate_group_table will re-allocate any
1305                          * metadata blocks whose location is set to zero.
1306                          */
1307                         if (ext2fs_block_bitmap_loc(fs, g) >= new_size) {
1308                                 ext2fs_block_bitmap_loc_set(fs, g, 0);
1309                                 realloc = 1;
1310                         }
1311                         if (ext2fs_inode_bitmap_loc(fs, g) >= new_size) {
1312                                 ext2fs_inode_bitmap_loc_set(fs, g, 0);
1313                                 realloc = 1;
1314                         }
1315                         if ((ext2fs_inode_table_loc(fs, g) +
1316                              fs->inode_blocks_per_group) > new_size) {
1317                                 ext2fs_inode_table_loc_set(fs, g, 0);
1318                                 realloc = 1;
1319                         }
1320
1321                         if (realloc) {
1322                                 retval = ext2fs_allocate_group_table(fs, g, 0);
1323                                 if (retval)
1324                                         return retval;
1325                         }
1326                 }
1327         }
1328
1329         /*
1330          * If we're shrinking the filesystem, we need to move all of
1331          * the blocks that don't fit any more
1332          */
1333         for (blk = ext2fs_blocks_count(fs->super);
1334              blk < ext2fs_blocks_count(old_fs->super); blk++) {
1335                 g = ext2fs_group_of_blk2(fs, blk);
1336                 if (ext2fs_has_group_desc_csum(fs) &&
1337                     ext2fs_bg_flags_test(old_fs, g, EXT2_BG_BLOCK_UNINIT)) {
1338                         /*
1339                          * The block bitmap is uninitialized, so skip
1340                          * to the next block group.
1341                          */
1342                         blk = ext2fs_group_first_block2(fs, g+1) - 1;
1343                         continue;
1344                 }
1345                 if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
1346                     !ext2fs_test_block_bitmap2(meta_bmap, blk)) {
1347                         ext2fs_mark_block_bitmap2(rfs->move_blocks, blk);
1348                         rfs->needed_blocks++;
1349                 }
1350                 ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
1351         }
1352
1353         if (ext2fs_has_feature_meta_bg(old_fs->super))
1354                 old_blocks = old_fs->super->s_first_meta_bg;
1355         else
1356                 old_blocks = old_fs->desc_blocks +
1357                         old_fs->super->s_reserved_gdt_blocks;
1358         if (ext2fs_has_feature_meta_bg(fs->super))
1359                 new_blocks = fs->super->s_first_meta_bg;
1360         else
1361                 new_blocks = fs->desc_blocks + fs->super->s_reserved_gdt_blocks;
1362
1363         retval = reserve_sparse_super2_last_group(rfs, meta_bmap);
1364         if (retval)
1365                 goto errout;
1366
1367         if (EXT2_DESC_SIZE(rfs->old_fs->super) ==
1368             EXT2_DESC_SIZE(rfs->new_fs->super) &&
1369             old_blocks == new_blocks) {
1370                 retval = 0;
1371                 goto errout;
1372         }
1373
1374         max_groups = fs->group_desc_count;
1375         if (max_groups > old_fs->group_desc_count)
1376                 max_groups = old_fs->group_desc_count;
1377         group_blk = old_fs->super->s_first_data_block;
1378         /*
1379          * If we're reducing the number of descriptor blocks, this
1380          * makes life easy.  :-)   We just have to mark some extra
1381          * blocks as free.
1382          */
1383         if (old_blocks > new_blocks) {
1384                 if (EXT2FS_CLUSTER_RATIO(fs) > 1) {
1385                         retval = ext2fs_allocate_block_bitmap(fs,
1386                                                         _("new meta blocks"),
1387                                                         &new_meta_bmap);
1388                         if (retval)
1389                                 goto errout;
1390
1391                         retval = mark_table_blocks(fs, new_meta_bmap);
1392                         if (retval)
1393                                 goto errout;
1394                 }
1395
1396                 for (i = 0; i < max_groups; i++) {
1397                         if (!ext2fs_bg_has_super(old_fs, i)) {
1398                                 group_blk += fs->super->s_blocks_per_group;
1399                                 continue;
1400                         }
1401                         group_end = group_blk + 1 + old_blocks;
1402                         for (blk = group_blk + 1 + new_blocks;
1403                              blk < group_end;) {
1404                                 if (new_meta_bmap == NULL ||
1405                                     !ext2fs_test_block_bitmap2(new_meta_bmap,
1406                                                                blk)) {
1407                                         cluster_freed =
1408                                                 EXT2FS_CLUSTER_RATIO(fs) -
1409                                                 (blk &
1410                                                  EXT2FS_CLUSTER_MASK(fs));
1411                                         if (cluster_freed > group_end - blk)
1412                                                 cluster_freed = group_end - blk;
1413                                         ext2fs_block_alloc_stats2(fs, blk, -1);
1414                                         blk += EXT2FS_CLUSTER_RATIO(fs);
1415                                         rfs->needed_blocks -= cluster_freed;
1416                                         continue;
1417                                 }
1418                                 rfs->needed_blocks--;
1419                                 blk++;
1420                         }
1421                         group_blk += fs->super->s_blocks_per_group;
1422                 }
1423                 retval = 0;
1424                 goto errout;
1425         }
1426         /*
1427          * If we're increasing the number of descriptor blocks, life
1428          * gets interesting....
1429          */
1430         meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
1431         flex_bg = ext2fs_has_feature_flex_bg(fs->super);
1432         /* first reserve all of the existing fs meta blocks */
1433         for (i = 0; i < max_groups; i++) {
1434                 has_super = ext2fs_bg_has_super(fs, i);
1435                 if (has_super)
1436                         mark_fs_metablock(rfs, meta_bmap, i, group_blk);
1437
1438                 meta_bg = i / meta_bg_size;
1439                 if (!ext2fs_has_feature_meta_bg(fs->super) ||
1440                     (meta_bg < fs->super->s_first_meta_bg)) {
1441                         if (has_super) {
1442                                 for (blk = group_blk+1;
1443                                      blk < group_blk + 1 + new_blocks; blk++)
1444                                         mark_fs_metablock(rfs, meta_bmap,
1445                                                           i, blk);
1446                         }
1447                 } else {
1448                         if (has_super)
1449                                 has_super = 1;
1450                         if (((i % meta_bg_size) == 0) ||
1451                             ((i % meta_bg_size) == 1) ||
1452                             ((i % meta_bg_size) == (meta_bg_size-1)))
1453                                 mark_fs_metablock(rfs, meta_bmap, i,
1454                                                   group_blk + has_super);
1455                 }
1456
1457                 /*
1458                  * Reserve the existing meta blocks that we know
1459                  * aren't to be moved.
1460                  *
1461                  * For flex_bg file systems, in order to avoid
1462                  * overwriting fs metadata (especially inode table
1463                  * blocks) belonging to a different block group when
1464                  * we are relocating the inode tables, we need to
1465                  * reserve all existing fs metadata blocks.
1466                  */
1467                 if (ext2fs_block_bitmap_loc(fs, i))
1468                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
1469                                  ext2fs_block_bitmap_loc(fs, i));
1470                 else if (flex_bg && i < old_fs->group_desc_count)
1471                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
1472                                  ext2fs_block_bitmap_loc(old_fs, i));
1473
1474                 if (ext2fs_inode_bitmap_loc(fs, i))
1475                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
1476                                  ext2fs_inode_bitmap_loc(fs, i));
1477                 else if (flex_bg && i < old_fs->group_desc_count)
1478                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
1479                                  ext2fs_inode_bitmap_loc(old_fs, i));
1480
1481                 if (ext2fs_inode_table_loc(fs, i))
1482                         ext2fs_mark_block_bitmap_range2(rfs->reserve_blocks,
1483                                         ext2fs_inode_table_loc(fs, i),
1484                                         fs->inode_blocks_per_group);
1485                 else if (flex_bg && i < old_fs->group_desc_count)
1486                         ext2fs_mark_block_bitmap_range2(rfs->reserve_blocks,
1487                                         ext2fs_inode_table_loc(old_fs, i),
1488                                         old_fs->inode_blocks_per_group);
1489
1490                 group_blk += rfs->new_fs->super->s_blocks_per_group;
1491         }
1492
1493         /* Allocate the missing data structures */
1494         for (i = 0; i < max_groups; i++) {
1495                 if (ext2fs_inode_table_loc(fs, i) &&
1496                     ext2fs_inode_bitmap_loc(fs, i) &&
1497                     ext2fs_block_bitmap_loc(fs, i))
1498                         continue;
1499
1500                 retval = ext2fs_allocate_group_table(fs, i,
1501                                                      rfs->reserve_blocks);
1502                 if (retval)
1503                         goto errout;
1504
1505                 /*
1506                  * For those structures that have changed, we need to
1507                  * do bookkeeping.
1508                  */
1509                 if (ext2fs_block_bitmap_loc(old_fs, i) !=
1510                     (blk = ext2fs_block_bitmap_loc(fs, i))) {
1511                         ext2fs_block_alloc_stats2(fs, blk, +1);
1512                         if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
1513                             !ext2fs_test_block_bitmap2(meta_bmap, blk))
1514                                 ext2fs_mark_block_bitmap2(rfs->move_blocks,
1515                                                          blk);
1516                 }
1517                 if (ext2fs_inode_bitmap_loc(old_fs, i) !=
1518                     (blk = ext2fs_inode_bitmap_loc(fs, i))) {
1519                         ext2fs_block_alloc_stats2(fs, blk, +1);
1520                         if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
1521                             !ext2fs_test_block_bitmap2(meta_bmap, blk))
1522                                 ext2fs_mark_block_bitmap2(rfs->move_blocks,
1523                                                          blk);
1524                 }
1525
1526                 /*
1527                  * The inode table, if we need to relocate it, is
1528                  * handled specially.  We have to reserve the blocks
1529                  * for both the old and the new inode table, since we
1530                  * can't have the inode table be destroyed during the
1531                  * block relocation phase.
1532                  */
1533                 if (ext2fs_inode_table_loc(fs, i) == ext2fs_inode_table_loc(old_fs, i))
1534                         continue;       /* inode table not moved */
1535
1536                 rfs->needed_blocks += fs->inode_blocks_per_group;
1537
1538                 /*
1539                  * Mark the new inode table as in use in the new block
1540                  * allocation bitmap, and move any blocks that might
1541                  * be necessary.
1542                  */
1543                 for (blk = ext2fs_inode_table_loc(fs, i), j=0;
1544                      j < fs->inode_blocks_per_group ; j++, blk++) {
1545                         ext2fs_block_alloc_stats2(fs, blk, +1);
1546                         if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
1547                             !ext2fs_test_block_bitmap2(meta_bmap, blk))
1548                                 ext2fs_mark_block_bitmap2(rfs->move_blocks,
1549                                                          blk);
1550                 }
1551
1552                 /*
1553                  * Make sure the old inode table is reserved in the
1554                  * block reservation bitmap.
1555                  */
1556                 for (blk = ext2fs_inode_table_loc(rfs->old_fs, i), j=0;
1557                      j < fs->inode_blocks_per_group ; j++, blk++)
1558                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
1559         }
1560         retval = 0;
1561
1562 errout:
1563         if (new_meta_bmap)
1564                 ext2fs_free_block_bitmap(new_meta_bmap);
1565         if (meta_bmap)
1566                 ext2fs_free_block_bitmap(meta_bmap);
1567
1568         return retval;
1569 }
1570
1571 /*
1572  * This helper function tries to allocate a new block.  We try to
1573  * avoid hitting the original group descriptor blocks at least at
1574  * first, since we want to make it possible to recover from a badly
1575  * aborted resize operation as much as possible.
1576  *
1577  * In the future, I may further modify this routine to balance out
1578  * where we get the new blocks across the various block groups.
1579  * Ideally we would allocate blocks that corresponded with the block
1580  * group of the containing inode, and keep contiguous blocks
1581  * together.  However, this very difficult to do efficiently, since we
1582  * don't have the necessary information up front.
1583  */
1584
1585 #define AVOID_OLD       1
1586 #define DESPERATION     2
1587
1588 static void init_block_alloc(ext2_resize_t rfs)
1589 {
1590         rfs->alloc_state = AVOID_OLD;
1591         rfs->new_blk = rfs->new_fs->super->s_first_data_block;
1592 #if 0
1593         /* HACK for testing */
1594         if (ext2fs_blocks_count(rfs->new_fs->super) >
1595             ext2fs_blocks_count(rfs->old_fs->super))
1596                 rfs->new_blk = ext2fs_blocks_count(rfs->old_fs->super);
1597 #endif
1598 }
1599
1600 static blk64_t get_new_block(ext2_resize_t rfs)
1601 {
1602         ext2_filsys     fs = rfs->new_fs;
1603
1604         while (1) {
1605                 if (rfs->new_blk >= ext2fs_blocks_count(fs->super)) {
1606                         if (rfs->alloc_state == DESPERATION)
1607                                 return 0;
1608
1609 #ifdef RESIZE2FS_DEBUG
1610                         if (rfs->flags & RESIZE_DEBUG_BMOVE)
1611                                 printf("Going into desperation mode "
1612                                        "for block allocations\n");
1613 #endif
1614                         rfs->alloc_state = DESPERATION;
1615                         rfs->new_blk = fs->super->s_first_data_block;
1616                         continue;
1617                 }
1618                 if (ext2fs_test_block_bitmap2(fs->block_map, rfs->new_blk) ||
1619                     ext2fs_test_block_bitmap2(rfs->reserve_blocks,
1620                                              rfs->new_blk) ||
1621                     ((rfs->alloc_state == AVOID_OLD) &&
1622                      (rfs->new_blk < ext2fs_blocks_count(rfs->old_fs->super)) &&
1623                      ext2fs_test_block_bitmap2(rfs->old_fs->block_map,
1624                                               rfs->new_blk))) {
1625                         rfs->new_blk++;
1626                         continue;
1627                 }
1628                 return rfs->new_blk;
1629         }
1630 }
1631
1632 static errcode_t resize2fs_get_alloc_block(ext2_filsys fs,
1633                                            blk64_t goal EXT2FS_ATTR((unused)),
1634                                            blk64_t *ret)
1635 {
1636         ext2_resize_t rfs = (ext2_resize_t) fs->priv_data;
1637         blk64_t blk;
1638         int group;
1639
1640         blk = get_new_block(rfs);
1641         if (!blk)
1642                 return ENOSPC;
1643
1644 #ifdef RESIZE2FS_DEBUG
1645         if (rfs->flags & 0xF)
1646                 printf("get_alloc_block allocating %llu\n", blk);
1647 #endif
1648
1649         ext2fs_mark_block_bitmap2(rfs->old_fs->block_map, blk);
1650         ext2fs_mark_block_bitmap2(rfs->new_fs->block_map, blk);
1651
1652         group = ext2fs_group_of_blk2(rfs->old_fs, blk);
1653         ext2fs_clear_block_uninit(rfs->old_fs, group);
1654         group = ext2fs_group_of_blk2(rfs->new_fs, blk);
1655         ext2fs_clear_block_uninit(rfs->new_fs, group);
1656
1657         *ret = (blk64_t) blk;
1658         return 0;
1659 }
1660
1661 static errcode_t block_mover(ext2_resize_t rfs)
1662 {
1663         blk64_t                 blk, old_blk, new_blk;
1664         ext2_filsys             fs = rfs->new_fs;
1665         ext2_filsys             old_fs = rfs->old_fs;
1666         errcode_t               retval;
1667         __u64                   c, size;
1668         int                     to_move, moved;
1669         ext2_badblocks_list     badblock_list = 0;
1670         int                     bb_modified = 0;
1671
1672         fs->get_alloc_block = resize2fs_get_alloc_block;
1673         old_fs->get_alloc_block = resize2fs_get_alloc_block;
1674
1675         retval = ext2fs_read_bb_inode(old_fs, &badblock_list);
1676         if (retval)
1677                 return retval;
1678
1679         new_blk = fs->super->s_first_data_block;
1680         if (!rfs->itable_buf) {
1681                 retval = ext2fs_get_array(fs->blocksize,
1682                                         fs->inode_blocks_per_group,
1683                                         &rfs->itable_buf);
1684                 if (retval)
1685                         return retval;
1686         }
1687         retval = ext2fs_create_extent_table(&rfs->bmap, 0);
1688         if (retval)
1689                 return retval;
1690
1691         /*
1692          * The first step is to figure out where all of the blocks
1693          * will go.
1694          */
1695         to_move = moved = 0;
1696         init_block_alloc(rfs);
1697         for (blk = B2C(old_fs->super->s_first_data_block);
1698              blk < ext2fs_blocks_count(old_fs->super);
1699              blk += EXT2FS_CLUSTER_RATIO(fs)) {
1700                 if (!ext2fs_test_block_bitmap2(old_fs->block_map, blk))
1701                         continue;
1702                 if (!ext2fs_test_block_bitmap2(rfs->move_blocks, blk))
1703                         continue;
1704                 if (ext2fs_badblocks_list_test(badblock_list, blk)) {
1705                         ext2fs_badblocks_list_del(badblock_list, blk);
1706                         bb_modified++;
1707                         continue;
1708                 }
1709
1710                 new_blk = get_new_block(rfs);
1711                 if (!new_blk) {
1712                         retval = ENOSPC;
1713                         goto errout;
1714                 }
1715                 ext2fs_block_alloc_stats2(fs, new_blk, +1);
1716                 ext2fs_add_extent_entry(rfs->bmap, B2C(blk), B2C(new_blk));
1717                 to_move++;
1718         }
1719
1720         if (to_move == 0) {
1721                 if (rfs->bmap) {
1722                         ext2fs_free_extent_table(rfs->bmap);
1723                         rfs->bmap = 0;
1724                 }
1725                 retval = 0;
1726                 goto errout;
1727         }
1728
1729         /*
1730          * Step two is to actually move the blocks
1731          */
1732         retval =  ext2fs_iterate_extent(rfs->bmap, 0, 0, 0);
1733         if (retval) goto errout;
1734
1735         if (rfs->progress) {
1736                 retval = (rfs->progress)(rfs, E2_RSZ_BLOCK_RELOC_PASS,
1737                                          0, to_move);
1738                 if (retval)
1739                         goto errout;
1740         }
1741         while (1) {
1742                 retval = ext2fs_iterate_extent(rfs->bmap, &old_blk, &new_blk, &size);
1743                 if (retval) goto errout;
1744                 if (!size)
1745                         break;
1746                 old_blk = C2B(old_blk);
1747                 new_blk = C2B(new_blk);
1748                 size = C2B(size);
1749 #ifdef RESIZE2FS_DEBUG
1750                 if (rfs->flags & RESIZE_DEBUG_BMOVE)
1751                         printf("Moving %llu blocks %llu->%llu\n",
1752                                size, old_blk, new_blk);
1753 #endif
1754                 do {
1755                         c = size;
1756                         if (c > fs->inode_blocks_per_group)
1757                                 c = fs->inode_blocks_per_group;
1758                         retval = io_channel_read_blk64(fs->io, old_blk, c,
1759                                                        rfs->itable_buf);
1760                         if (retval) goto errout;
1761                         retval = io_channel_write_blk64(fs->io, new_blk, c,
1762                                                         rfs->itable_buf);
1763                         if (retval) goto errout;
1764                         size -= c;
1765                         new_blk += c;
1766                         old_blk += c;
1767                         moved += c;
1768                         if (rfs->progress) {
1769                                 io_channel_flush(fs->io);
1770                                 retval = (rfs->progress)(rfs,
1771                                                 E2_RSZ_BLOCK_RELOC_PASS,
1772                                                 moved, to_move);
1773                                 if (retval)
1774                                         goto errout;
1775                         }
1776                 } while (size > 0);
1777                 io_channel_flush(fs->io);
1778         }
1779
1780 errout:
1781         if (badblock_list) {
1782                 if (!retval && bb_modified)
1783                         retval = ext2fs_update_bb_inode(old_fs,
1784                                                         badblock_list);
1785                 ext2fs_badblocks_list_free(badblock_list);
1786         }
1787         return retval;
1788 }
1789
1790
1791 /* --------------------------------------------------------------------
1792  *
1793  * Resize processing, phase 3
1794  *
1795  * --------------------------------------------------------------------
1796  */
1797
1798
1799 /*
1800  * The extent translation table is stored in clusters so we need to
1801  * take special care when mapping a source block number to its
1802  * destination block number.
1803  */
1804 static __u64 extent_translate(ext2_filsys fs, ext2_extent extent, __u64 old_loc)
1805 {
1806         __u64 new_block = C2B(ext2fs_extent_translate(extent, B2C(old_loc)));
1807
1808         if (new_block != 0)
1809                 new_block += old_loc & (EXT2FS_CLUSTER_RATIO(fs) - 1);
1810         return new_block;
1811 }
1812
1813 struct process_block_struct {
1814         ext2_resize_t           rfs;
1815         ext2_ino_t              ino;
1816         ext2_ino_t              old_ino;
1817         struct ext2_inode *     inode;
1818         errcode_t               error;
1819         int                     is_dir;
1820         int                     changed;
1821         int                     has_extents;
1822 };
1823
1824 static int process_block(ext2_filsys fs, blk64_t        *block_nr,
1825                          e2_blkcnt_t blockcnt,
1826                          blk64_t ref_block EXT2FS_ATTR((unused)),
1827                          int ref_offset EXT2FS_ATTR((unused)), void *priv_data)
1828 {
1829         struct process_block_struct *pb;
1830         errcode_t       retval;
1831         blk64_t         block, new_block;
1832         int             ret = 0;
1833
1834         pb = (struct process_block_struct *) priv_data;
1835         block = *block_nr;
1836         if (pb->rfs->bmap) {
1837                 new_block = extent_translate(fs, pb->rfs->bmap, block);
1838                 if (new_block) {
1839                         *block_nr = new_block;
1840                         ret |= BLOCK_CHANGED;
1841                         pb->changed = 1;
1842 #ifdef RESIZE2FS_DEBUG
1843                         if (pb->rfs->flags & RESIZE_DEBUG_BMOVE)
1844                                 printf("ino=%u, blockcnt=%lld, %llu->%llu\n",
1845                                        pb->old_ino, blockcnt, block,
1846                                        new_block);
1847 #endif
1848                         block = new_block;
1849                 }
1850         }
1851
1852         if (pb->is_dir) {
1853                 retval = ext2fs_add_dir_block2(fs->dblist, pb->ino,
1854                                                block, (int) blockcnt);
1855                 if (retval) {
1856                         pb->error = retval;
1857                         ret |= BLOCK_ABORT;
1858                 }
1859         }
1860         return ret;
1861 }
1862
1863 /*
1864  * Progress callback
1865  */
1866 static errcode_t progress_callback(ext2_filsys fs,
1867                                    ext2_inode_scan scan EXT2FS_ATTR((unused)),
1868                                    dgrp_t group, void * priv_data)
1869 {
1870         ext2_resize_t rfs = (ext2_resize_t) priv_data;
1871         errcode_t               retval;
1872
1873         /*
1874          * This check is to protect against old ext2 libraries.  It
1875          * shouldn't be needed against new libraries.
1876          */
1877         if ((group+1) == 0)
1878                 return 0;
1879
1880         if (rfs->progress) {
1881                 io_channel_flush(fs->io);
1882                 retval = (rfs->progress)(rfs, E2_RSZ_INODE_SCAN_PASS,
1883                                          group+1, fs->group_desc_count);
1884                 if (retval)
1885                         return retval;
1886         }
1887
1888         return 0;
1889 }
1890
1891 static errcode_t migrate_ea_block(ext2_resize_t rfs, ext2_ino_t ino,
1892                                   struct ext2_inode *inode, int *changed)
1893 {
1894         char *buf = NULL;
1895         blk64_t new_block;
1896         errcode_t err = 0;
1897
1898         /* No EA block or no remapping?  Quit early. */
1899         if (ext2fs_file_acl_block(rfs->old_fs, inode) == 0 || !rfs->bmap)
1900                 return 0;
1901         new_block = extent_translate(rfs->old_fs, rfs->bmap,
1902                 ext2fs_file_acl_block(rfs->old_fs, inode));
1903         if (new_block == 0)
1904                 return 0;
1905
1906         /* Set the new ACL block */
1907         ext2fs_file_acl_block_set(rfs->old_fs, inode, new_block);
1908
1909         /* Update checksum */
1910         if (ext2fs_has_feature_metadata_csum(rfs->new_fs->super)) {
1911                 err = ext2fs_get_mem(rfs->old_fs->blocksize, &buf);
1912                 if (err)
1913                         return err;
1914                 rfs->old_fs->flags |= EXT2_FLAG_IGNORE_CSUM_ERRORS;
1915                 err = ext2fs_read_ext_attr3(rfs->old_fs, new_block, buf, ino);
1916                 rfs->old_fs->flags &= ~EXT2_FLAG_IGNORE_CSUM_ERRORS;
1917                 if (err)
1918                         goto out;
1919                 err = ext2fs_write_ext_attr3(rfs->old_fs, new_block, buf, ino);
1920                 if (err)
1921                         goto out;
1922         }
1923         *changed = 1;
1924
1925 out:
1926         ext2fs_free_mem(&buf);
1927         return err;
1928 }
1929
1930 /* Rewrite extents */
1931 static errcode_t rewrite_extents(ext2_filsys fs, ext2_ino_t ino)
1932 {
1933         ext2_extent_handle_t    handle;
1934         struct ext2fs_extent    extent;
1935         errcode_t               errcode;
1936         struct ext2_extent_info info;
1937
1938         errcode = ext2fs_extent_open(fs, ino, &handle);
1939         if (errcode)
1940                 return errcode;
1941
1942         errcode = ext2fs_extent_get(handle, EXT2_EXTENT_ROOT, &extent);
1943         if (errcode)
1944                 goto out;
1945
1946         do {
1947                 errcode = ext2fs_extent_get_info(handle, &info);
1948                 if (errcode)
1949                         break;
1950
1951                 /*
1952                  * If this is the first extent in an extent block that we
1953                  * haven't visited, rewrite the extent to force the ETB
1954                  * checksum to be rewritten.
1955                  */
1956                 if (info.curr_entry == 1 && info.curr_level != 0 &&
1957                     !(extent.e_flags & EXT2_EXTENT_FLAGS_SECOND_VISIT)) {
1958                         errcode = ext2fs_extent_replace(handle, 0, &extent);
1959                         if (errcode)
1960                                 break;
1961                 }
1962
1963                 /* Skip to the end of a block of leaf nodes */
1964                 if (extent.e_flags & EXT2_EXTENT_FLAGS_LEAF) {
1965                         errcode = ext2fs_extent_get(handle,
1966                                                     EXT2_EXTENT_LAST_SIB,
1967                                                     &extent);
1968                         if (errcode)
1969                                 break;
1970                 }
1971
1972                 errcode = ext2fs_extent_get(handle, EXT2_EXTENT_NEXT, &extent);
1973         } while (errcode == 0);
1974
1975 out:
1976         /* Ok if we run off the end */
1977         if (errcode == EXT2_ET_EXTENT_NO_NEXT)
1978                 errcode = 0;
1979         ext2fs_extent_free(handle);
1980         return errcode;
1981 }
1982
1983 static void quiet_com_err_proc(const char *whoami EXT2FS_ATTR((unused)),
1984                                errcode_t code EXT2FS_ATTR((unused)),
1985                                const char *fmt EXT2FS_ATTR((unused)),
1986                                va_list args EXT2FS_ATTR((unused)))
1987 {
1988 }
1989
1990 static int fix_ea_entries(ext2_extent imap, struct ext2_ext_attr_entry *entry,
1991                           struct ext2_ext_attr_entry *end, ext2_ino_t last_ino)
1992 {
1993         int modified = 0;
1994         ext2_ino_t new_ino;
1995
1996         while (entry < end && !EXT2_EXT_IS_LAST_ENTRY(entry)) {
1997                 if (entry->e_value_inum > last_ino) {
1998                         new_ino = ext2fs_extent_translate(imap,
1999                                                           entry->e_value_inum);
2000                         entry->e_value_inum = new_ino;
2001                         modified = 1;
2002                 }
2003                 entry = EXT2_EXT_ATTR_NEXT(entry);
2004         }
2005         return modified;
2006 }
2007
2008 static int fix_ea_ibody_entries(ext2_extent imap,
2009                                 struct ext2_inode_large *inode, int inode_size,
2010                                 ext2_ino_t last_ino)
2011 {
2012         struct ext2_ext_attr_entry *start, *end;
2013         __u32 *ea_magic;
2014
2015         if (inode->i_extra_isize == 0)
2016                 return 0;
2017
2018         ea_magic = (__u32 *)((char *)inode + EXT2_GOOD_OLD_INODE_SIZE +
2019                                 inode->i_extra_isize);
2020         if (*ea_magic != EXT2_EXT_ATTR_MAGIC)
2021                 return 0;
2022
2023         start = (struct ext2_ext_attr_entry *)(ea_magic + 1);
2024         end = (struct ext2_ext_attr_entry *)((char *)inode + inode_size);
2025
2026         return fix_ea_entries(imap, start, end, last_ino);
2027 }
2028
2029 static int fix_ea_block_entries(ext2_extent imap, char *block_buf,
2030                                 unsigned int blocksize, ext2_ino_t last_ino)
2031 {
2032         struct ext2_ext_attr_header *header;
2033         struct ext2_ext_attr_entry *start, *end;
2034
2035         header = (struct ext2_ext_attr_header *)block_buf;
2036         start = (struct ext2_ext_attr_entry *)(header+1);
2037         end = (struct ext2_ext_attr_entry *)(block_buf + blocksize);
2038
2039         return fix_ea_entries(imap, start, end, last_ino);
2040 }
2041
2042 /* A simple LRU cache to check recently processed blocks. */
2043 struct blk_cache {
2044         int cursor;
2045         blk64_t blks[4];
2046 };
2047
2048 #define BLK_IN_CACHE(b,c) ((b) == (c).blks[0] || (b) == (c).blks[1] || \
2049                            (b) == (c).blks[2] || (b) == (c).blks[3])
2050 #define BLK_ADD_CACHE(b,c) {                    \
2051         (c).blks[(c).cursor] = (b);             \
2052         (c).cursor = ((c).cursor + 1) % 4;      \
2053 }
2054
2055 static errcode_t fix_ea_inode_refs(ext2_resize_t rfs, struct ext2_inode *inode,
2056                                    char *block_buf, ext2_ino_t last_ino)
2057 {
2058         ext2_filsys     fs = rfs->new_fs;
2059         ext2_inode_scan scan = NULL;
2060         ext2_ino_t      ino;
2061         int             inode_size = EXT2_INODE_SIZE(fs->super);
2062         blk64_t         blk;
2063         int             modified;
2064         struct blk_cache blk_cache;
2065         struct ext2_ext_attr_header *header;
2066         errcode_t               retval;
2067
2068         memset(&blk_cache, 0, sizeof(blk_cache));
2069
2070         header = (struct ext2_ext_attr_header *)block_buf;
2071
2072         retval = ext2fs_open_inode_scan(fs, 0, &scan);
2073         if (retval)
2074                 goto out;
2075
2076         while (1) {
2077                 retval = ext2fs_get_next_inode_full(scan, &ino, inode,
2078                                                     inode_size);
2079                 if (retval)
2080                         goto out;
2081                 if (!ino)
2082                         break;
2083
2084                 if (inode->i_links_count == 0 && ino != EXT2_RESIZE_INO)
2085                         continue; /* inode not in use */
2086
2087                 if (inode_size != EXT2_GOOD_OLD_INODE_SIZE) {
2088                         modified = fix_ea_ibody_entries(rfs->imap,
2089                                         (struct ext2_inode_large *)inode,
2090                                         inode_size, last_ino);
2091                         if (modified) {
2092                                 retval = ext2fs_write_inode_full(fs, ino, inode,
2093                                                                  inode_size);
2094                                 if (retval)
2095                                         goto out;
2096                         }
2097                 }
2098
2099                 blk = ext2fs_file_acl_block(fs, inode);
2100                 if (blk && !BLK_IN_CACHE(blk, blk_cache)) {
2101                         retval = ext2fs_read_ext_attr3(fs, blk, block_buf, ino);
2102                         if (retval)
2103                                 goto out;
2104
2105                         modified = fix_ea_block_entries(rfs->imap, block_buf,
2106                                                         fs->blocksize,
2107                                                         last_ino);
2108                         if (modified) {
2109                                 retval = ext2fs_write_ext_attr3(fs, blk,
2110                                                                 block_buf, ino);
2111                                 if (retval)
2112                                         goto out;
2113                                 /*
2114                                  * If refcount is greater than 1, we might see
2115                                  * the same block referenced by other inodes
2116                                  * later.
2117                                  */
2118                                 if (header->h_refcount > 1)
2119                                         BLK_ADD_CACHE(blk, blk_cache);
2120                         }
2121                 }
2122         }
2123         retval = 0;
2124 out:
2125         if (scan)
2126                 ext2fs_close_inode_scan(scan);
2127         return retval;
2128
2129 }
2130 static errcode_t inode_scan_and_fix(ext2_resize_t rfs)
2131 {
2132         struct process_block_struct     pb;
2133         ext2_ino_t              ino, new_inode;
2134         struct ext2_inode       *inode = NULL;
2135         ext2_inode_scan         scan = NULL;
2136         errcode_t               retval;
2137         char                    *block_buf = 0;
2138         ext2_ino_t              start_to_move;
2139         int                     inode_size;
2140         int                     update_ea_inode_refs = 0;
2141
2142         if ((rfs->old_fs->group_desc_count <=
2143              rfs->new_fs->group_desc_count) &&
2144             !rfs->bmap)
2145                 return 0;
2146
2147         set_com_err_hook(quiet_com_err_proc);
2148
2149         retval = ext2fs_open_inode_scan(rfs->old_fs, 0, &scan);
2150         if (retval) goto errout;
2151
2152         retval = ext2fs_init_dblist(rfs->old_fs, 0);
2153         if (retval) goto errout;
2154         retval = ext2fs_get_array(rfs->old_fs->blocksize, 3, &block_buf);
2155         if (retval) goto errout;
2156
2157         start_to_move = (rfs->new_fs->group_desc_count *
2158                          rfs->new_fs->super->s_inodes_per_group);
2159
2160         if (rfs->progress) {
2161                 retval = (rfs->progress)(rfs, E2_RSZ_INODE_SCAN_PASS,
2162                                          0, rfs->old_fs->group_desc_count);
2163                 if (retval)
2164                         goto errout;
2165         }
2166         ext2fs_set_inode_callback(scan, progress_callback, (void *) rfs);
2167         pb.rfs = rfs;
2168         pb.inode = inode;
2169         pb.error = 0;
2170         new_inode = EXT2_FIRST_INODE(rfs->new_fs->super);
2171         inode_size = EXT2_INODE_SIZE(rfs->new_fs->super);
2172         inode = malloc(inode_size);
2173         if (!inode) {
2174                 retval = ENOMEM;
2175                 goto errout;
2176         }
2177         /*
2178          * First, copy all of the inodes that need to be moved
2179          * elsewhere in the inode table
2180          */
2181         while (1) {
2182                 retval = ext2fs_get_next_inode_full(scan, &ino, inode, inode_size);
2183                 if (retval) goto errout;
2184                 if (!ino)
2185                         break;
2186
2187                 if (inode->i_links_count == 0 && ino != EXT2_RESIZE_INO)
2188                         continue; /* inode not in use */
2189
2190                 pb.is_dir = LINUX_S_ISDIR(inode->i_mode);
2191                 pb.changed = 0;
2192
2193                 /* Remap EA block */
2194                 retval = migrate_ea_block(rfs, ino, inode, &pb.changed);
2195                 if (retval)
2196                         goto errout;
2197
2198                 new_inode = ino;
2199                 if (ino <= start_to_move)
2200                         goto remap_blocks; /* Don't need to move inode. */
2201
2202                 /*
2203                  * Find a new inode.  Now that extents and directory blocks
2204                  * are tied to the inode number through the checksum, we must
2205                  * set up the new inode before we start rewriting blocks.
2206                  */
2207                 retval = ext2fs_new_inode(rfs->new_fs, 0, 0, 0, &new_inode);
2208                 if (retval)
2209                         goto errout;
2210
2211                 ext2fs_inode_alloc_stats2(rfs->new_fs, new_inode, +1,
2212                                           pb.is_dir);
2213                 /*
2214                  * i_ctime field in xattr inodes contain a portion of the ref
2215                  * count, do not overwrite.
2216                  */
2217                 if (inode->i_flags & EXT4_EA_INODE_FL)
2218                         update_ea_inode_refs = 1;
2219                 else
2220                         inode->i_ctime = time(0);
2221
2222                 retval = ext2fs_write_inode_full(rfs->old_fs, new_inode,
2223                                                 inode, inode_size);
2224                 if (retval)
2225                         goto errout;
2226                 pb.changed = 0;
2227
2228 #ifdef RESIZE2FS_DEBUG
2229                 if (rfs->flags & RESIZE_DEBUG_INODEMAP)
2230                         printf("Inode moved %u->%u\n", ino, new_inode);
2231 #endif
2232                 if (!rfs->imap) {
2233                         retval = ext2fs_create_extent_table(&rfs->imap, 0);
2234                         if (retval)
2235                                 goto errout;
2236                 }
2237                 ext2fs_add_extent_entry(rfs->imap, ino, new_inode);
2238
2239 remap_blocks:
2240                 if (pb.changed)
2241                         retval = ext2fs_write_inode_full(rfs->old_fs,
2242                                                          new_inode,
2243                                                          inode, inode_size);
2244                 if (retval)
2245                         goto errout;
2246
2247                 /*
2248                  * Update inodes to point to new blocks; schedule directory
2249                  * blocks for inode remapping.  Need to write out dir blocks
2250                  * with new inode numbers if we have metadata_csum enabled.
2251                  */
2252                 rfs->old_fs->flags |= EXT2_FLAG_IGNORE_CSUM_ERRORS;
2253                 if (ext2fs_inode_has_valid_blocks2(rfs->old_fs, inode) &&
2254                     (rfs->bmap || pb.is_dir)) {
2255                         pb.ino = new_inode;
2256                         pb.old_ino = ino;
2257                         pb.has_extents = inode->i_flags & EXT4_EXTENTS_FL;
2258                         retval = ext2fs_block_iterate3(rfs->old_fs,
2259                                                        new_inode, 0, block_buf,
2260                                                        process_block, &pb);
2261                         if (retval)
2262                                 goto errout;
2263                         if (pb.error) {
2264                                 retval = pb.error;
2265                                 goto errout;
2266                         }
2267                 } else if ((inode->i_flags & EXT4_INLINE_DATA_FL) &&
2268                            (rfs->bmap || pb.is_dir)) {
2269                         /* inline data dir; update it too */
2270                         retval = ext2fs_add_dir_block2(rfs->old_fs->dblist,
2271                                                        new_inode, 0, 0);
2272                         if (retval)
2273                                 goto errout;
2274                 }
2275
2276                 /* Fix up extent block checksums with the new inode number */
2277                 if (ext2fs_has_feature_metadata_csum(rfs->old_fs->super) &&
2278                     (inode->i_flags & EXT4_EXTENTS_FL)) {
2279                         retval = rewrite_extents(rfs->old_fs, new_inode);
2280                         if (retval)
2281                                 goto errout;
2282                 }
2283         }
2284
2285         if (update_ea_inode_refs &&
2286             ext2fs_has_feature_ea_inode(rfs->new_fs->super)) {
2287                 retval = fix_ea_inode_refs(rfs, inode, block_buf,
2288                                            start_to_move);
2289                 if (retval)
2290                         goto errout;
2291         }
2292         io_channel_flush(rfs->old_fs->io);
2293
2294 errout:
2295         reset_com_err_hook();
2296         rfs->old_fs->flags &= ~EXT2_FLAG_IGNORE_CSUM_ERRORS;
2297         if (rfs->bmap) {
2298                 ext2fs_free_extent_table(rfs->bmap);
2299                 rfs->bmap = 0;
2300         }
2301         if (scan)
2302                 ext2fs_close_inode_scan(scan);
2303         if (block_buf)
2304                 ext2fs_free_mem(&block_buf);
2305         free(inode);
2306         return retval;
2307 }
2308
2309 /* --------------------------------------------------------------------
2310  *
2311  * Resize processing, phase 4.
2312  *
2313  * --------------------------------------------------------------------
2314  */
2315
2316 struct istruct {
2317         ext2_resize_t rfs;
2318         errcode_t       err;
2319         unsigned int    max_dirs;
2320         unsigned int    num;
2321 };
2322
2323 static int check_and_change_inodes(ext2_ino_t dir,
2324                                    int entry EXT2FS_ATTR((unused)),
2325                                    struct ext2_dir_entry *dirent, int offset,
2326                                    int  blocksize EXT2FS_ATTR((unused)),
2327                                    char *buf EXT2FS_ATTR((unused)),
2328                                    void *priv_data)
2329 {
2330         struct istruct *is = (struct istruct *) priv_data;
2331         struct ext2_inode       inode;
2332         ext2_ino_t              new_inode;
2333         errcode_t               retval;
2334         int                     ret = 0;
2335
2336         if (is->rfs->progress && offset == 0) {
2337                 io_channel_flush(is->rfs->old_fs->io);
2338                 is->err = (is->rfs->progress)(is->rfs,
2339                                               E2_RSZ_INODE_REF_UPD_PASS,
2340                                               ++is->num, is->max_dirs);
2341                 if (is->err)
2342                         return DIRENT_ABORT;
2343         }
2344
2345         /*
2346          * If we have checksums enabled and the inode wasn't present in the
2347          * old fs, then we must rewrite all dir blocks with new checksums.
2348          */
2349         if (ext2fs_has_feature_metadata_csum(is->rfs->old_fs->super) &&
2350             !ext2fs_test_inode_bitmap2(is->rfs->old_fs->inode_map, dir))
2351                 ret |= DIRENT_CHANGED;
2352
2353         if (!dirent->inode)
2354                 return ret;
2355
2356         new_inode = ext2fs_extent_translate(is->rfs->imap, dirent->inode);
2357
2358         if (!new_inode)
2359                 return ret;
2360 #ifdef RESIZE2FS_DEBUG
2361         if (is->rfs->flags & RESIZE_DEBUG_INODEMAP)
2362                 printf("Inode translate (dir=%u, name=%.*s, %u->%u)\n",
2363                        dir, ext2fs_dirent_name_len(dirent), dirent->name,
2364                        dirent->inode, new_inode);
2365 #endif
2366
2367         dirent->inode = new_inode;
2368
2369         /* Update the directory mtime and ctime */
2370         retval = ext2fs_read_inode(is->rfs->old_fs, dir, &inode);
2371         if (retval == 0) {
2372                 inode.i_mtime = inode.i_ctime = time(0);
2373                 is->err = ext2fs_write_inode(is->rfs->old_fs, dir, &inode);
2374                 if (is->err)
2375                         return ret | DIRENT_ABORT;
2376         }
2377
2378         return ret | DIRENT_CHANGED;
2379 }
2380
2381 static errcode_t inode_ref_fix(ext2_resize_t rfs)
2382 {
2383         errcode_t               retval;
2384         struct istruct          is;
2385
2386         if (!rfs->imap)
2387                 return 0;
2388
2389         /*
2390          * Now, we iterate over all of the directories to update the
2391          * inode references
2392          */
2393         is.num = 0;
2394         is.max_dirs = ext2fs_dblist_count2(rfs->old_fs->dblist);
2395         is.rfs = rfs;
2396         is.err = 0;
2397
2398         if (rfs->progress) {
2399                 retval = (rfs->progress)(rfs, E2_RSZ_INODE_REF_UPD_PASS,
2400                                          0, is.max_dirs);
2401                 if (retval)
2402                         goto errout;
2403         }
2404
2405         rfs->old_fs->flags |= EXT2_FLAG_IGNORE_CSUM_ERRORS;
2406         retval = ext2fs_dblist_dir_iterate(rfs->old_fs->dblist,
2407                                            DIRENT_FLAG_INCLUDE_EMPTY, 0,
2408                                            check_and_change_inodes, &is);
2409         rfs->old_fs->flags &= ~EXT2_FLAG_IGNORE_CSUM_ERRORS;
2410         if (retval)
2411                 goto errout;
2412         if (is.err) {
2413                 retval = is.err;
2414                 goto errout;
2415         }
2416
2417         if (rfs->progress && (is.num < is.max_dirs))
2418                 (rfs->progress)(rfs, E2_RSZ_INODE_REF_UPD_PASS,
2419                                 is.max_dirs, is.max_dirs);
2420
2421 errout:
2422         ext2fs_free_extent_table(rfs->imap);
2423         rfs->imap = 0;
2424         return retval;
2425 }
2426
2427
2428 /* --------------------------------------------------------------------
2429  *
2430  * Resize processing, phase 5.
2431  *
2432  * In this phase we actually move the inode table around, and then
2433  * update the summary statistics.  This is scary, since aborting here
2434  * will potentially scramble the filesystem.  (We are moving the
2435  * inode tables around in place, and so the potential for lost data,
2436  * or at the very least scrambling the mapping between filenames and
2437  * inode numbers is very high in case of a power failure here.)
2438  * --------------------------------------------------------------------
2439  */
2440
2441
2442 /*
2443  * A very scary routine --- this one moves the inode table around!!!
2444  *
2445  * After this you have to use the rfs->new_fs file handle to read and
2446  * write inodes.
2447  */
2448 static errcode_t move_itables(ext2_resize_t rfs)
2449 {
2450         int             n, num, size;
2451         long long       diff;
2452         dgrp_t          i, max_groups;
2453         ext2_filsys     fs = rfs->new_fs;
2454         char            *cp;
2455         blk64_t         old_blk, new_blk, blk, cluster_freed;
2456         errcode_t       retval;
2457         int             to_move, moved;
2458         unsigned int    j;
2459         ext2fs_block_bitmap     new_bmap = NULL;
2460
2461         max_groups = fs->group_desc_count;
2462         if (max_groups > rfs->old_fs->group_desc_count)
2463                 max_groups = rfs->old_fs->group_desc_count;
2464
2465         size = fs->blocksize * fs->inode_blocks_per_group;
2466         if (!rfs->itable_buf) {
2467                 retval = ext2fs_get_mem(size, &rfs->itable_buf);
2468                 if (retval)
2469                         return retval;
2470         }
2471
2472         if (EXT2FS_CLUSTER_RATIO(fs) > 1) {
2473                 retval = ext2fs_allocate_block_bitmap(fs, _("new meta blocks"),
2474                                                       &new_bmap);
2475                 if (retval)
2476                         return retval;
2477
2478                 retval = mark_table_blocks(fs, new_bmap);
2479                 if (retval)
2480                         goto errout;
2481         }
2482
2483         /*
2484          * Figure out how many inode tables we need to move
2485          */
2486         to_move = moved = 0;
2487         for (i=0; i < max_groups; i++)
2488                 if (ext2fs_inode_table_loc(rfs->old_fs, i) !=
2489                     ext2fs_inode_table_loc(fs, i))
2490                         to_move++;
2491
2492         if (to_move == 0) {
2493                 retval = 0;
2494                 goto errout;
2495         }
2496
2497         if (rfs->progress) {
2498                 retval = rfs->progress(rfs, E2_RSZ_MOVE_ITABLE_PASS,
2499                                        0, to_move);
2500                 if (retval)
2501                         goto errout;
2502         }
2503
2504         rfs->old_fs->flags |= EXT2_FLAG_MASTER_SB_ONLY;
2505
2506         for (i=0; i < max_groups; i++) {
2507                 old_blk = ext2fs_inode_table_loc(rfs->old_fs, i);
2508                 new_blk = ext2fs_inode_table_loc(fs, i);
2509                 diff = new_blk - old_blk;
2510
2511 #ifdef RESIZE2FS_DEBUG
2512                 if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
2513                         printf("Itable move group %d block %llu->%llu (diff %lld)\n",
2514                                i, old_blk, new_blk, diff);
2515 #endif
2516
2517                 if (!diff)
2518                         continue;
2519                 if (diff < 0)
2520                         diff = 0;
2521
2522                 retval = io_channel_read_blk64(fs->io, old_blk,
2523                                                fs->inode_blocks_per_group,
2524                                                rfs->itable_buf);
2525                 if (retval)
2526                         goto errout;
2527                 /*
2528                  * The end of the inode table segment often contains
2529                  * all zeros, and we're often only moving the inode
2530                  * table down a block or two.  If so, we can optimize
2531                  * things by not rewriting blocks that we know to be zero
2532                  * already.
2533                  */
2534                 for (cp = rfs->itable_buf+size-1, n=0; n < size; n++, cp--)
2535                         if (*cp)
2536                                 break;
2537                 n = n >> EXT2_BLOCK_SIZE_BITS(fs->super);
2538 #ifdef RESIZE2FS_DEBUG
2539                 if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
2540                         printf("%d blocks of zeros...\n", n);
2541 #endif
2542                 num = fs->inode_blocks_per_group;
2543                 if (n > diff)
2544                         num -= n;
2545
2546                 retval = io_channel_write_blk64(fs->io, new_blk,
2547                                                 num, rfs->itable_buf);
2548                 if (retval) {
2549                         io_channel_write_blk64(fs->io, old_blk,
2550                                                num, rfs->itable_buf);
2551                         goto errout;
2552                 }
2553                 if (n > diff) {
2554                         retval = io_channel_write_blk64(fs->io,
2555                               old_blk + fs->inode_blocks_per_group,
2556                               diff, (rfs->itable_buf +
2557                                      (fs->inode_blocks_per_group - diff) *
2558                                      fs->blocksize));
2559                         if (retval)
2560                                 goto errout;
2561                 }
2562
2563                 for (blk = ext2fs_inode_table_loc(rfs->old_fs, i), j=0;
2564                      j < fs->inode_blocks_per_group;) {
2565                         if (new_bmap == NULL ||
2566                             !ext2fs_test_block_bitmap2(new_bmap, blk)) {
2567                                 ext2fs_block_alloc_stats2(fs, blk, -1);
2568                                 cluster_freed = EXT2FS_CLUSTER_RATIO(fs) -
2569                                                 (blk & EXT2FS_CLUSTER_MASK(fs));
2570                                 blk += cluster_freed;
2571                                 j += cluster_freed;
2572                                 continue;
2573                         }
2574                         blk++;
2575                         j++;
2576                 }
2577
2578                 ext2fs_inode_table_loc_set(rfs->old_fs, i, new_blk);
2579                 ext2fs_group_desc_csum_set(rfs->old_fs, i);
2580                 ext2fs_mark_super_dirty(rfs->old_fs);
2581                 ext2fs_flush(rfs->old_fs);
2582
2583                 if (rfs->progress) {
2584                         retval = rfs->progress(rfs, E2_RSZ_MOVE_ITABLE_PASS,
2585                                                ++moved, to_move);
2586                         if (retval)
2587                                 goto errout;
2588                 }
2589         }
2590         mark_table_blocks(fs, fs->block_map);
2591         ext2fs_flush(fs);
2592 #ifdef RESIZE2FS_DEBUG
2593         if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
2594                 printf("Inode table move finished.\n");
2595 #endif
2596         retval = 0;
2597
2598 errout:
2599         if (new_bmap)
2600                 ext2fs_free_block_bitmap(new_bmap);
2601         return retval;
2602 }
2603
2604 /*
2605  * This function is used when expanding a file system.  It frees the
2606  * superblock and block group descriptor blocks from the block group
2607  * which is no longer the last block group.
2608  */
2609 static errcode_t clear_sparse_super2_last_group(ext2_resize_t rfs)
2610 {
2611         ext2_filsys     fs = rfs->new_fs;
2612         ext2_filsys     old_fs = rfs->old_fs;
2613         errcode_t       retval;
2614         dgrp_t          old_last_bg = rfs->old_fs->group_desc_count - 1;
2615         dgrp_t          last_bg = fs->group_desc_count - 1;
2616         blk64_t         sb, old_desc;
2617         blk_t           num;
2618
2619         if (!ext2fs_has_feature_sparse_super2(fs->super))
2620                 return 0;
2621
2622         if (last_bg <= old_last_bg)
2623                 return 0;
2624
2625         if (fs->super->s_backup_bgs[0] == old_fs->super->s_backup_bgs[0] &&
2626             fs->super->s_backup_bgs[1] == old_fs->super->s_backup_bgs[1])
2627                 return 0;
2628
2629         if (old_fs->super->s_backup_bgs[0] != old_last_bg &&
2630             old_fs->super->s_backup_bgs[1] != old_last_bg)
2631                 return 0;
2632
2633         if (fs->super->s_backup_bgs[0] == old_last_bg ||
2634             fs->super->s_backup_bgs[1] == old_last_bg)
2635                 return 0;
2636
2637         if (old_last_bg == 0)
2638                 return 0;
2639
2640         retval = ext2fs_super_and_bgd_loc2(rfs->old_fs, old_last_bg,
2641                                            &sb, &old_desc, NULL, &num);
2642         if (retval)
2643                 return retval;
2644
2645         if (sb)
2646                 ext2fs_unmark_block_bitmap2(fs->block_map, sb);
2647         if (old_desc)
2648                 ext2fs_unmark_block_bitmap_range2(fs->block_map, old_desc, num);
2649         return 0;
2650 }
2651
2652 /*
2653  * This function is used when shrinking a file system.  We need to
2654  * utilize blocks from what will be the new last block group for the
2655  * backup superblock and block group descriptor blocks.
2656  * Unfortunately, those blocks may be used by other files or fs
2657  * metadata blocks.  We need to mark them as being in use.
2658  */
2659 static errcode_t reserve_sparse_super2_last_group(ext2_resize_t rfs,
2660                                                  ext2fs_block_bitmap meta_bmap)
2661 {
2662         ext2_filsys     fs = rfs->new_fs;
2663         ext2_filsys     old_fs = rfs->old_fs;
2664         errcode_t       retval;
2665         dgrp_t          old_last_bg = rfs->old_fs->group_desc_count - 1;
2666         dgrp_t          last_bg = fs->group_desc_count - 1;
2667         dgrp_t          g;
2668         blk64_t         blk, sb, old_desc;
2669         blk_t           i, num;
2670         int             realloc = 0;
2671
2672         if (!ext2fs_has_feature_sparse_super2(fs->super))
2673                 return 0;
2674
2675         if (last_bg >= old_last_bg)
2676                 return 0;
2677
2678         if (fs->super->s_backup_bgs[0] == old_fs->super->s_backup_bgs[0] &&
2679             fs->super->s_backup_bgs[1] == old_fs->super->s_backup_bgs[1])
2680                 return 0;
2681
2682         if (fs->super->s_backup_bgs[0] != last_bg &&
2683             fs->super->s_backup_bgs[1] != last_bg)
2684                 return 0;
2685
2686         if (old_fs->super->s_backup_bgs[0] == last_bg ||
2687             old_fs->super->s_backup_bgs[1] == last_bg)
2688                 return 0;
2689
2690         retval = ext2fs_super_and_bgd_loc2(rfs->new_fs, last_bg,
2691                                            &sb, &old_desc, NULL, &num);
2692         if (retval)
2693                 return retval;
2694
2695         if (last_bg && !sb) {
2696                 fputs(_("Should never happen!  No sb in last super_sparse bg?\n"),
2697                       stderr);
2698                 exit(1);
2699         }
2700         if (old_desc && old_desc != sb+1) {
2701                 fputs(_("Should never happen!  Unexpected old_desc in "
2702                         "super_sparse bg?\n"),
2703                       stderr);
2704                 exit(1);
2705         }
2706         num = (old_desc) ? num : 1;
2707
2708         /* Reserve the backup blocks */
2709         ext2fs_mark_block_bitmap_range2(fs->block_map, sb, num);
2710
2711         for (g = 0; g < fs->group_desc_count; g++) {
2712                 blk64_t mb;
2713
2714                 mb = ext2fs_block_bitmap_loc(fs, g);
2715                 if ((mb >= sb) && (mb < sb + num)) {
2716                         ext2fs_block_bitmap_loc_set(fs, g, 0);
2717                         realloc = 1;
2718                 }
2719                 mb = ext2fs_inode_bitmap_loc(fs, g);
2720                 if ((mb >= sb) && (mb < sb + num)) {
2721                         ext2fs_inode_bitmap_loc_set(fs, g, 0);
2722                         realloc = 1;
2723                 }
2724                 mb = ext2fs_inode_table_loc(fs, g);
2725                 if ((mb < sb + num) &&
2726                     (sb < mb + fs->inode_blocks_per_group)) {
2727                         ext2fs_inode_table_loc_set(fs, g, 0);
2728                         realloc = 1;
2729                 }
2730                 if (realloc) {
2731                         retval = ext2fs_allocate_group_table(fs, g, 0);
2732                         if (retval)
2733                                 return retval;
2734                 }
2735         }
2736
2737         for (blk = sb, i = 0; i < num; blk++, i++) {
2738                 if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
2739                     !ext2fs_test_block_bitmap2(meta_bmap, blk)) {
2740                         ext2fs_mark_block_bitmap2(rfs->move_blocks, blk);
2741                         rfs->needed_blocks++;
2742                 }
2743                 ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
2744         }
2745         return 0;
2746 }
2747
2748 /*
2749  * Fix the resize inode
2750  */
2751 static errcode_t fix_resize_inode(ext2_filsys fs)
2752 {
2753         struct ext2_inode       inode;
2754         errcode_t               retval;
2755
2756         if (!ext2fs_has_feature_resize_inode(fs->super))
2757                 return 0;
2758
2759         retval = ext2fs_read_inode(fs, EXT2_RESIZE_INO, &inode);
2760         if (retval) goto errout;
2761
2762         ext2fs_iblk_set(fs, &inode, 1);
2763
2764         retval = ext2fs_write_inode(fs, EXT2_RESIZE_INO, &inode);
2765         if (retval) goto errout;
2766
2767         if (!inode.i_block[EXT2_DIND_BLOCK]) {
2768                 /*
2769                  * Avoid zeroing out block #0; that's rude.  This
2770                  * should never happen anyway since the filesystem
2771                  * should be fsck'ed and we assume it is consistent.
2772                  */
2773                 fprintf(stderr, "%s",
2774                         _("Should never happen: resize inode corrupt!\n"));
2775                 exit(1);
2776         }
2777
2778         retval = ext2fs_zero_blocks2(fs, inode.i_block[EXT2_DIND_BLOCK], 1,
2779                                      NULL, NULL);
2780         if (retval)
2781                 goto errout;
2782
2783         retval = ext2fs_create_resize_inode(fs);
2784         if (retval)
2785                 goto errout;
2786
2787 errout:
2788         return retval;
2789 }
2790
2791 /*
2792  * Finally, recalculate the summary information
2793  */
2794 static errcode_t ext2fs_calculate_summary_stats(ext2_filsys fs)
2795 {
2796         blk64_t         blk;
2797         ext2_ino_t      ino;
2798         unsigned int    group = 0;
2799         unsigned int    count = 0;
2800         blk64_t         total_blocks_free = 0;
2801         int             total_inodes_free = 0;
2802         int             group_free = 0;
2803         int             uninit = 0;
2804         blk64_t         super_blk, old_desc_blk, new_desc_blk;
2805         int             old_desc_blocks;
2806
2807         /*
2808          * First calculate the block statistics
2809          */
2810         uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_BLOCK_UNINIT);
2811         ext2fs_super_and_bgd_loc2(fs, group, &super_blk, &old_desc_blk,
2812                                   &new_desc_blk, 0);
2813         if (ext2fs_has_feature_meta_bg(fs->super))
2814                 old_desc_blocks = fs->super->s_first_meta_bg;
2815         else
2816                 old_desc_blocks = fs->desc_blocks +
2817                         fs->super->s_reserved_gdt_blocks;
2818         for (blk = B2C(fs->super->s_first_data_block);
2819              blk < ext2fs_blocks_count(fs->super);
2820              blk += EXT2FS_CLUSTER_RATIO(fs)) {
2821                 if ((uninit &&
2822                      !(EQ_CLSTR(blk, super_blk) ||
2823                        ((old_desc_blk && old_desc_blocks &&
2824                          GE_CLSTR(blk, old_desc_blk) &&
2825                          LT_CLSTR(blk, old_desc_blk + old_desc_blocks))) ||
2826                        ((new_desc_blk && EQ_CLSTR(blk, new_desc_blk))) ||
2827                        EQ_CLSTR(blk, ext2fs_block_bitmap_loc(fs, group)) ||
2828                        EQ_CLSTR(blk, ext2fs_inode_bitmap_loc(fs, group)) ||
2829                        ((GE_CLSTR(blk, ext2fs_inode_table_loc(fs, group)) &&
2830                          LT_CLSTR(blk, ext2fs_inode_table_loc(fs, group)
2831                                   + fs->inode_blocks_per_group))))) ||
2832                     (!ext2fs_fast_test_block_bitmap2(fs->block_map, blk))) {
2833                         group_free++;
2834                         total_blocks_free++;
2835                 }
2836                 count++;
2837                 if ((count == fs->super->s_clusters_per_group) ||
2838                     EQ_CLSTR(blk, ext2fs_blocks_count(fs->super)-1)) {
2839                         ext2fs_bg_free_blocks_count_set(fs, group, group_free);
2840                         ext2fs_group_desc_csum_set(fs, group);
2841                         group++;
2842                         if (group >= fs->group_desc_count)
2843                                 break;
2844                         count = 0;
2845                         group_free = 0;
2846                         uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_BLOCK_UNINIT);
2847                         ext2fs_super_and_bgd_loc2(fs, group, &super_blk,
2848                                                   &old_desc_blk,
2849                                                   &new_desc_blk, 0);
2850                         if (ext2fs_has_feature_meta_bg(fs->super))
2851                                 old_desc_blocks = fs->super->s_first_meta_bg;
2852                         else
2853                                 old_desc_blocks = fs->desc_blocks +
2854                                         fs->super->s_reserved_gdt_blocks;
2855                 }
2856         }
2857         total_blocks_free = C2B(total_blocks_free);
2858         ext2fs_free_blocks_count_set(fs->super, total_blocks_free);
2859
2860         /*
2861          * Next, calculate the inode statistics
2862          */
2863         group_free = 0;
2864         count = 0;
2865         group = 0;
2866
2867         /* Protect loop from wrap-around if s_inodes_count maxed */
2868         uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_INODE_UNINIT);
2869         for (ino = 1; ino <= fs->super->s_inodes_count && ino > 0; ino++) {
2870                 if (uninit ||
2871                     !ext2fs_fast_test_inode_bitmap2(fs->inode_map, ino)) {
2872                         group_free++;
2873                         total_inodes_free++;
2874                 }
2875                 count++;
2876                 if ((count == fs->super->s_inodes_per_group) ||
2877                     (ino == fs->super->s_inodes_count)) {
2878                         ext2fs_bg_free_inodes_count_set(fs, group, group_free);
2879                         ext2fs_group_desc_csum_set(fs, group);
2880                         group++;
2881                         if (group >= fs->group_desc_count)
2882                                 break;
2883                         count = 0;
2884                         group_free = 0;
2885                         uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_INODE_UNINIT);
2886                 }
2887         }
2888         fs->super->s_free_inodes_count = total_inodes_free;
2889         ext2fs_mark_super_dirty(fs);
2890         return 0;
2891 }
2892
2893 /*
2894  *  Journal may have been relocated; update the backup journal blocks
2895  *  in the superblock.
2896  */
2897 static errcode_t fix_sb_journal_backup(ext2_filsys fs)
2898 {
2899         errcode_t         retval;
2900         struct ext2_inode inode;
2901
2902         if (!ext2fs_has_feature_journal(fs->super))
2903                 return 0;
2904
2905         /* External journal? Nothing to do. */
2906         if (fs->super->s_journal_dev && !fs->super->s_journal_inum)
2907                 return 0;
2908
2909         retval = ext2fs_read_inode(fs, fs->super->s_journal_inum, &inode);
2910         if (retval)
2911                 return retval;
2912         memcpy(fs->super->s_jnl_blocks, inode.i_block, EXT2_N_BLOCKS*4);
2913         fs->super->s_jnl_blocks[15] = inode.i_size_high;
2914         fs->super->s_jnl_blocks[16] = inode.i_size;
2915         fs->super->s_jnl_backup_type = EXT3_JNL_BACKUP_BLOCKS;
2916         ext2fs_mark_super_dirty(fs);
2917         return 0;
2918 }
2919
2920 static int calc_group_overhead(ext2_filsys fs, blk64_t grp,
2921                                int old_desc_blocks)
2922 {
2923         blk64_t super_blk, old_desc_blk, new_desc_blk;
2924         int overhead;
2925
2926         /* inode table blocks plus allocation bitmaps */
2927         overhead = fs->inode_blocks_per_group + 2;
2928
2929         ext2fs_super_and_bgd_loc2(fs, grp, &super_blk,
2930                                   &old_desc_blk, &new_desc_blk, 0);
2931         if ((grp == 0) || super_blk)
2932                 overhead++;
2933         if (old_desc_blk)
2934                 overhead += old_desc_blocks;
2935         else if (new_desc_blk)
2936                 overhead++;
2937         return overhead;
2938 }
2939
2940
2941 /*
2942  * calculate the minimum number of blocks the given fs can be resized to
2943  */
2944 blk64_t calculate_minimum_resize_size(ext2_filsys fs, int flags)
2945 {
2946         ext2_ino_t inode_count;
2947         dgrp_t groups, flex_groups;
2948         blk64_t blks_needed, data_blocks;
2949         blk64_t grp, data_needed, last_start;
2950         blk64_t overhead = 0;
2951         int old_desc_blocks;
2952         int flexbg_size = 1 << fs->super->s_log_groups_per_flex;
2953
2954         /*
2955          * first figure out how many group descriptors we need to
2956          * handle the number of inodes we have
2957          */
2958         inode_count = fs->super->s_inodes_count -
2959                 fs->super->s_free_inodes_count;
2960         blks_needed = ext2fs_div_ceil(inode_count,
2961                                       fs->super->s_inodes_per_group) *
2962                 (blk64_t) EXT2_BLOCKS_PER_GROUP(fs->super);
2963         groups = ext2fs_div64_ceil(blks_needed,
2964                                    EXT2_BLOCKS_PER_GROUP(fs->super));
2965 #ifdef RESIZE2FS_DEBUG
2966         if (flags & RESIZE_DEBUG_MIN_CALC)
2967                 printf("fs has %d inodes, %d groups required.\n",
2968                        inode_count, groups);
2969 #endif
2970
2971         /*
2972          * number of old-style block group descriptor blocks
2973          */
2974         if (ext2fs_has_feature_meta_bg(fs->super))
2975                 old_desc_blocks = fs->super->s_first_meta_bg;
2976         else
2977                 old_desc_blocks = fs->desc_blocks +
2978                         fs->super->s_reserved_gdt_blocks;
2979
2980         /* calculate how many blocks are needed for data */
2981         data_needed = ext2fs_blocks_count(fs->super) -
2982                 ext2fs_free_blocks_count(fs->super);
2983
2984         for (grp = 0; grp < fs->group_desc_count; grp++)
2985                 data_needed -= calc_group_overhead(fs, grp, old_desc_blocks);
2986 #ifdef RESIZE2FS_DEBUG
2987         if (flags & RESIZE_DEBUG_MIN_CALC)
2988                 printf("fs requires %llu data blocks.\n", data_needed);
2989 #endif
2990
2991         /*
2992          * For ext4 we need to allow for up to a flex_bg worth of
2993          * inode tables of slack space so the resize operation can be
2994          * guaranteed to finish.
2995          */
2996         flex_groups = groups;
2997         if (ext2fs_has_feature_flex_bg(fs->super)) {
2998                 dgrp_t remainder = groups & (flexbg_size - 1);
2999
3000                 flex_groups += flexbg_size - remainder;
3001                 if (flex_groups > fs->group_desc_count)
3002                         flex_groups = fs->group_desc_count;
3003         }
3004
3005         /*
3006          * figure out how many data blocks we have given the number of groups
3007          * we need for our inodes
3008          */
3009         data_blocks = EXT2_GROUPS_TO_BLOCKS(fs->super, groups);
3010         last_start = 0;
3011         for (grp = 0; grp < flex_groups; grp++) {
3012                 overhead = calc_group_overhead(fs, grp, old_desc_blocks);
3013
3014                 /*
3015                  * we want to keep track of how much data we can store in
3016                  * the groups leading up to the last group so we can determine
3017                  * how big the last group needs to be
3018                  */
3019                 if (grp < (groups - 1))
3020                         last_start += EXT2_BLOCKS_PER_GROUP(fs->super) -
3021                                 overhead;
3022
3023                 if (data_blocks > overhead)
3024                         data_blocks -= overhead;
3025                 else
3026                         data_blocks = 0;
3027         }
3028 #ifdef RESIZE2FS_DEBUG
3029         if (flags & RESIZE_DEBUG_MIN_CALC)
3030                 printf("With %d group(s), we have %llu blocks available.\n",
3031                        groups, data_blocks);
3032 #endif
3033
3034         /*
3035          * if we need more group descriptors in order to accommodate our data
3036          * then we need to add them here
3037          */
3038         blks_needed = data_needed;
3039         while (blks_needed > data_blocks) {
3040                 blk64_t remainder = blks_needed - data_blocks;
3041                 dgrp_t extra_grps;
3042
3043                 /* figure out how many more groups we need for the data */
3044                 extra_grps = ext2fs_div64_ceil(remainder,
3045                                                EXT2_BLOCKS_PER_GROUP(fs->super));
3046
3047                 data_blocks += EXT2_GROUPS_TO_BLOCKS(fs->super, extra_grps);
3048
3049                 /* ok we have to account for the last group */
3050                 overhead = calc_group_overhead(fs, groups-1, old_desc_blocks);
3051                 last_start += EXT2_BLOCKS_PER_GROUP(fs->super) - overhead;
3052
3053                 grp = flex_groups;
3054                 groups += extra_grps;
3055                 if (!ext2fs_has_feature_flex_bg(fs->super))
3056                         flex_groups = groups;
3057                 else if (groups > flex_groups) {
3058                         dgrp_t r = groups & (flexbg_size - 1);
3059
3060                         flex_groups = groups + flexbg_size - r;
3061                         if (flex_groups > fs->group_desc_count)
3062                                 flex_groups = fs->group_desc_count;
3063                 }
3064
3065                 for (; grp < flex_groups; grp++) {
3066                         overhead = calc_group_overhead(fs, grp,
3067                                                        old_desc_blocks);
3068
3069                         /*
3070                          * again, we need to see how much data we cram into
3071                          * all of the groups leading up to the last group
3072                          */
3073                         if (grp < groups - 1)
3074                                 last_start += EXT2_BLOCKS_PER_GROUP(fs->super)
3075                                         - overhead;
3076
3077                         data_blocks -= overhead;
3078                 }
3079
3080 #ifdef RESIZE2FS_DEBUG
3081                 if (flags & RESIZE_DEBUG_MIN_CALC)
3082                         printf("Added %d extra group(s), "
3083                                "blks_needed %llu, data_blocks %llu, "
3084                                "last_start %llu\n", extra_grps, blks_needed,
3085                                data_blocks, last_start);
3086 #endif
3087         }
3088
3089         /* now for the fun voodoo */
3090         grp = groups - 1;
3091         if (ext2fs_has_feature_flex_bg(fs->super) &&
3092             (grp & ~(flexbg_size - 1)) == 0)
3093                 grp = grp & ~(flexbg_size - 1);
3094         overhead = 0;
3095         for (; grp < flex_groups; grp++)
3096                 overhead += calc_group_overhead(fs, grp, old_desc_blocks);
3097
3098 #ifdef RESIZE2FS_DEBUG
3099         if (flags & RESIZE_DEBUG_MIN_CALC)
3100                 printf("Last group's overhead is %llu\n", overhead);
3101 #endif
3102
3103         /*
3104          * if this is the case then the last group is going to have data in it
3105          * so we need to adjust the size of the last group accordingly
3106          */
3107         if (last_start < blks_needed) {
3108                 blk64_t remainder = blks_needed - last_start;
3109
3110 #ifdef RESIZE2FS_DEBUG
3111                 if (flags & RESIZE_DEBUG_MIN_CALC)
3112                         printf("Need %llu data blocks in last group\n",
3113                                remainder);
3114 #endif
3115                 /*
3116                  * 50 is a magic number that mkfs/resize uses to see if its
3117                  * even worth making/resizing the fs.  basically you need to
3118                  * have at least 50 blocks in addition to the blocks needed
3119                  * for the metadata in the last group
3120                  */
3121                 if (remainder > 50)
3122                         overhead += remainder;
3123                 else
3124                         overhead += 50;
3125         } else
3126                 overhead += 50;
3127
3128         overhead += fs->super->s_first_data_block;
3129 #ifdef RESIZE2FS_DEBUG
3130         if (flags & RESIZE_DEBUG_MIN_CALC)
3131                 printf("Final size of last group is %lld\n", overhead);
3132 #endif
3133
3134         /* Add extra slack for bigalloc file systems */
3135         if (EXT2FS_CLUSTER_RATIO(fs) > 1)
3136                 overhead += EXT2FS_CLUSTER_RATIO(fs) * 2;
3137
3138         /*
3139          * since our last group doesn't have to be BLOCKS_PER_GROUP
3140          * large, we only do groups-1, and then add the number of
3141          * blocks needed to handle the group descriptor metadata+data
3142          * that we need
3143          */
3144         blks_needed = EXT2_GROUPS_TO_BLOCKS(fs->super, groups - 1);
3145         blks_needed += overhead;
3146
3147         /*
3148          * Make sure blks_needed covers the end of the inode table in
3149          * the last block group.
3150          */
3151         overhead = ext2fs_inode_table_loc(fs, groups-1) +
3152                 fs->inode_blocks_per_group;
3153         if (blks_needed < overhead)
3154                 blks_needed = overhead;
3155
3156 #ifdef RESIZE2FS_DEBUG
3157         if (flags & RESIZE_DEBUG_MIN_CALC)
3158                 printf("Estimated blocks needed: %llu\n", blks_needed);
3159 #endif
3160
3161         /*
3162          * If at this point we've already added up more "needed" than
3163          * the current size, just return current size as minimum.
3164          */
3165         if (blks_needed >= ext2fs_blocks_count(fs->super))
3166                 return ext2fs_blocks_count(fs->super);
3167         /*
3168          * We need to reserve a few extra blocks if extents are
3169          * enabled, in case we need to grow the extent tree.  The more
3170          * we shrink the file system, the more space we need.
3171          *
3172          * The absolute worst case is every single data block is in
3173          * the part of the file system that needs to be evacuated,
3174          * with each data block needs to be in its own extent, and
3175          * with each inode needing at least one extent block.
3176          */
3177         if (ext2fs_has_feature_extents(fs->super)) {
3178                 blk64_t safe_margin = (ext2fs_blocks_count(fs->super) -
3179                                        blks_needed)/500;
3180                 unsigned int exts_per_blk = (fs->blocksize /
3181                                              sizeof(struct ext3_extent)) - 1;
3182                 blk64_t worst_case = ((data_needed + exts_per_blk - 1) /
3183                                       exts_per_blk);
3184
3185                 if (worst_case < inode_count)
3186                         worst_case = inode_count;
3187
3188                 if (safe_margin > worst_case)
3189                         safe_margin = worst_case;
3190
3191 #ifdef RESIZE2FS_DEBUG
3192                 if (flags & RESIZE_DEBUG_MIN_CALC)
3193                         printf("Extents safety margin: %llu\n", safe_margin);
3194 #endif
3195                 blks_needed += safe_margin;
3196         }
3197
3198         return blks_needed;
3199 }