resize/resize2fs.c

   1 /*
   2  * resize2fs.c --- ext2 main routine
   3  *
   4  * Copyright (C) 1997, 1998 by Theodore Ts'o and
   5  *      PowerQuest, Inc.
   6  *
   7  * Copyright (C) 1999, 2000 by Theosore Ts'o
   8  *
   9  * %Begin-Header%
  10  * This file may be redistributed under the terms of the GNU Public
  11  * License.
  12  * %End-Header%
  13  */
  14
  15 /*
  16  * Resizing a filesystem consists of the following phases:
  17  *
  18  *      1.  Adjust superblock and write out new parts of the inode
  19  *              table
  20  *      2.  Determine blocks which need to be relocated, and copy the
  21  *              contents of blocks from their old locations to the new ones.
  22  *      3.  Scan the inode table, doing the following:
  23  *              a.  If blocks have been moved, update the block
  24  *                      pointers in the inodes and indirect blocks to
  25  *                      point at the new block locations.
  26  *              b.  If parts of the inode table need to be evacuated,
  27  *                      copy inodes from their old locations to their
  28  *                      new ones.
  29  *              c.  If (b) needs to be done, note which blocks contain
  30  *                      directory information, since we will need to
  31  *                      update the directory information.
  32  *      4.  Update the directory blocks with the new inode locations.
  33  *      5.  Move the inode tables, if necessary.
  34  */
  35
  36 #include "config.h"
  37 #include "resize2fs.h"
  38 #include <time.h>
  39
  40 #ifdef __linux__                        /* Kludge for debugging */
  41 #define RESIZE2FS_DEBUG
  42 #endif
  43
  44 static void fix_uninit_block_bitmaps(ext2_filsys fs);
  45 static errcode_t adjust_superblock(ext2_resize_t rfs, blk64_t new_size);
  46 static errcode_t blocks_to_move(ext2_resize_t rfs);
  47 static errcode_t block_mover(ext2_resize_t rfs);
  48 static errcode_t inode_scan_and_fix(ext2_resize_t rfs);
  49 static errcode_t inode_ref_fix(ext2_resize_t rfs);
  50 static errcode_t move_itables(ext2_resize_t rfs);
  51 static errcode_t fix_resize_inode(ext2_filsys fs);
  52 static errcode_t ext2fs_calculate_summary_stats(ext2_filsys fs);
  53 static errcode_t fix_sb_journal_backup(ext2_filsys fs);
  54 static errcode_t mark_table_blocks(ext2_filsys fs,
  55                                    ext2fs_block_bitmap bmap);
  56
  57 /*
  58  * Some helper CPP macros
  59  */
  60 #define IS_BLOCK_BM(fs, i, blk) ((blk) == ext2fs_block_bitmap_loc((fs),(i)))
  61 #define IS_INODE_BM(fs, i, blk) ((blk) == ext2fs_inode_bitmap_loc((fs),(i)))
  62
  63 #define IS_INODE_TB(fs, i, blk) (((blk) >= ext2fs_inode_table_loc((fs), (i))) && \
  64                                  ((blk) < (ext2fs_inode_table_loc((fs), (i)) + \
  65                                            (fs)->inode_blocks_per_group)))
  66
  67 /* Some bigalloc helper macros which are more succint... */
  68 #define B2C(x)  EXT2FS_B2C(fs, (x))
  69 #define C2B(x)  EXT2FS_C2B(fs, (x))
  70 #define EQ_CLSTR(x, y) (B2C(x) == B2C(y))
  71 #define LE_CLSTR(x, y) (B2C(x) <= B2C(y))
  72 #define LT_CLSTR(x, y) (B2C(x) <  B2C(y))
  73 #define GE_CLSTR(x, y) (B2C(x) >= B2C(y))
  74 #define GT_CLSTR(x, y) (B2C(x) >  B2C(y))
  75
  76 int lazy_itable_init;
  77
  78 /*
  79  * This is the top-level routine which does the dirty deed....
  80  */
  81 errcode_t resize_fs(ext2_filsys fs, blk64_t *new_size, int flags,
  82             errcode_t (*progress)(ext2_resize_t rfs, int pass,
  83                                           unsigned long cur,
  84                                           unsigned long max_val))
  85 {
  86         ext2_resize_t   rfs;
  87         errcode_t       retval;
  88         struct resource_track   rtrack, overall_track;
  89
  90         /*
  91          * Create the data structure
  92          */
  93         retval = ext2fs_get_mem(sizeof(struct ext2_resize_struct), &rfs);
  94         if (retval)
  95                 return retval;
  96
  97         memset(rfs, 0, sizeof(struct ext2_resize_struct));
  98         fs->priv_data = rfs;
  99         rfs->old_fs = fs;
 100         rfs->flags = flags;
 101         rfs->itable_buf  = 0;
 102         rfs->progress = progress;
 103
 104         init_resource_track(&overall_track, "overall resize2fs", fs->io);
 105         init_resource_track(&rtrack, "read_bitmaps", fs->io);
 106         retval = ext2fs_read_bitmaps(fs);
 107         if (retval)
 108                 goto errout;
 109         print_resource_track(rfs, &rtrack, fs->io);
 110
 111         fs->super->s_state |= EXT2_ERROR_FS;
 112         ext2fs_mark_super_dirty(fs);
 113         ext2fs_flush(fs);
 114
 115         init_resource_track(&rtrack, "fix_uninit_block_bitmaps 1", fs->io);
 116         fix_uninit_block_bitmaps(fs);
 117         print_resource_track(rfs, &rtrack, fs->io);
 118         retval = ext2fs_dup_handle(fs, &rfs->new_fs);
 119         if (retval)
 120                 goto errout;
 121
 122         init_resource_track(&rtrack, "adjust_superblock", fs->io);
 123         retval = adjust_superblock(rfs, *new_size);
 124         if (retval)
 125                 goto errout;
 126         print_resource_track(rfs, &rtrack, fs->io);
 127
 128
 129         init_resource_track(&rtrack, "fix_uninit_block_bitmaps 2", fs->io);
 130         fix_uninit_block_bitmaps(rfs->new_fs);
 131         print_resource_track(rfs, &rtrack, fs->io);
 132         /* Clear the block bitmap uninit flag for the last block group */
 133         ext2fs_bg_flags_clear(rfs->new_fs, rfs->new_fs->group_desc_count - 1,
 134                              EXT2_BG_BLOCK_UNINIT);
 135
 136         *new_size = ext2fs_blocks_count(rfs->new_fs->super);
 137
 138         init_resource_track(&rtrack, "blocks_to_move", fs->io);
 139         retval = blocks_to_move(rfs);
 140         if (retval)
 141                 goto errout;
 142         print_resource_track(rfs, &rtrack, fs->io);
 143
 144 #ifdef RESIZE2FS_DEBUG
 145         if (rfs->flags & RESIZE_DEBUG_BMOVE)
 146                 printf("Number of free blocks: %llu/%llu, Needed: %llu\n",
 147                        ext2fs_free_blocks_count(rfs->old_fs->super),
 148                        ext2fs_free_blocks_count(rfs->new_fs->super),
 149                        rfs->needed_blocks);
 150 #endif
 151
 152         init_resource_track(&rtrack, "block_mover", fs->io);
 153         retval = block_mover(rfs);
 154         if (retval)
 155                 goto errout;
 156         print_resource_track(rfs, &rtrack, fs->io);
 157
 158         init_resource_track(&rtrack, "inode_scan_and_fix", fs->io);
 159         retval = inode_scan_and_fix(rfs);
 160         if (retval)
 161                 goto errout;
 162         print_resource_track(rfs, &rtrack, fs->io);
 163
 164         init_resource_track(&rtrack, "inode_ref_fix", fs->io);
 165         retval = inode_ref_fix(rfs);
 166         if (retval)
 167                 goto errout;
 168         print_resource_track(rfs, &rtrack, fs->io);
 169
 170         init_resource_track(&rtrack, "move_itables", fs->io);
 171         retval = move_itables(rfs);
 172         if (retval)
 173                 goto errout;
 174         print_resource_track(rfs, &rtrack, fs->io);
 175
 176         init_resource_track(&rtrack, "calculate_summary_stats", fs->io);
 177         retval = ext2fs_calculate_summary_stats(rfs->new_fs);
 178         if (retval)
 179                 goto errout;
 180         print_resource_track(rfs, &rtrack, fs->io);
 181
 182         init_resource_track(&rtrack, "fix_resize_inode", fs->io);
 183         retval = fix_resize_inode(rfs->new_fs);
 184         if (retval)
 185                 goto errout;
 186         print_resource_track(rfs, &rtrack, fs->io);
 187
 188         init_resource_track(&rtrack, "fix_sb_journal_backup", fs->io);
 189         retval = fix_sb_journal_backup(rfs->new_fs);
 190         if (retval)
 191                 goto errout;
 192         print_resource_track(rfs, &rtrack, fs->io);
 193
 194         rfs->new_fs->super->s_state &= ~EXT2_ERROR_FS;
 195         rfs->new_fs->flags &= ~EXT2_FLAG_MASTER_SB_ONLY;
 196
 197         print_resource_track(rfs, &overall_track, fs->io);
 198         retval = ext2fs_close(rfs->new_fs);
 199         if (retval)
 200                 goto errout;
 201
 202         rfs->flags = flags;
 203
 204         ext2fs_free(rfs->old_fs);
 205         if (rfs->itable_buf)
 206                 ext2fs_free_mem(&rfs->itable_buf);
 207         if (rfs->reserve_blocks)
 208                 ext2fs_free_block_bitmap(rfs->reserve_blocks);
 209         if (rfs->move_blocks)
 210                 ext2fs_free_block_bitmap(rfs->move_blocks);
 211         ext2fs_free_mem(&rfs);
 212
 213         return 0;
 214
 215 errout:
 216         if (rfs->new_fs)
 217                 ext2fs_free(rfs->new_fs);
 218         if (rfs->itable_buf)
 219                 ext2fs_free_mem(&rfs->itable_buf);
 220         ext2fs_free_mem(&rfs);
 221         return retval;
 222 }
 223
 224 /*
 225  * Clean up the bitmaps for unitialized bitmaps
 226  */
 227 static void fix_uninit_block_bitmaps(ext2_filsys fs)
 228 {
 229         blk64_t         blk, lblk;
 230         dgrp_t          g;
 231         int             i;
 232
 233         if (!ext2fs_has_group_desc_csum(fs))
 234                 return;
 235
 236         for (g=0; g < fs->group_desc_count; g++) {
 237                 if (!(ext2fs_bg_flags_test(fs, g, EXT2_BG_BLOCK_UNINIT)))
 238                         continue;
 239
 240                 blk = ext2fs_group_first_block2(fs, g);
 241                 lblk = ext2fs_group_last_block2(fs, g);
 242                 ext2fs_unmark_block_bitmap_range2(fs->block_map, blk,
 243                                                   lblk - blk + 1);
 244
 245                 ext2fs_reserve_super_and_bgd(fs, g, fs->block_map);
 246                 ext2fs_mark_block_bitmap2(fs->block_map,
 247                                           ext2fs_block_bitmap_loc(fs, g));
 248                 ext2fs_mark_block_bitmap2(fs->block_map,
 249                                           ext2fs_inode_bitmap_loc(fs, g));
 250                 for (i = 0, blk = ext2fs_inode_table_loc(fs, g);
 251                      i < (unsigned int) fs->inode_blocks_per_group;
 252                      i++, blk++)
 253                         ext2fs_mark_block_bitmap2(fs->block_map, blk);
 254         }
 255 }
 256
 257 /* --------------------------------------------------------------------
 258  *
 259  * Resize processing, phase 1.
 260  *
 261  * In this phase we adjust the in-memory superblock information, and
 262  * initialize any new parts of the inode table.  The new parts of the
 263  * inode table are created in virgin disk space, so we can abort here
 264  * without any side effects.
 265  * --------------------------------------------------------------------
 266  */
 267
 268 /*
 269  * If the group descriptor's bitmap and inode table blocks are valid,
 270  * release them in the new filesystem data structure, and mark them as
 271  * reserved so the old inode table blocks don't get overwritten.
 272  */
 273 static void free_gdp_blocks(ext2_filsys fs,
 274                             ext2fs_block_bitmap reserve_blocks,
 275                             struct ext2_group_desc *gdp)
 276 {
 277         blk_t   blk;
 278         int     j;
 279
 280         if (gdp->bg_block_bitmap &&
 281             (gdp->bg_block_bitmap < ext2fs_blocks_count(fs->super))) {
 282                 ext2fs_block_alloc_stats(fs, gdp->bg_block_bitmap, -1);
 283                 ext2fs_mark_block_bitmap2(reserve_blocks,
 284                                          gdp->bg_block_bitmap);
 285         }
 286
 287         if (gdp->bg_inode_bitmap &&
 288             (gdp->bg_inode_bitmap < ext2fs_blocks_count(fs->super))) {
 289                 ext2fs_block_alloc_stats(fs, gdp->bg_inode_bitmap, -1);
 290                 ext2fs_mark_block_bitmap2(reserve_blocks,
 291                                          gdp->bg_inode_bitmap);
 292         }
 293
 294         if (gdp->bg_inode_table == 0 ||
 295             (gdp->bg_inode_table >= ext2fs_blocks_count(fs->super)))
 296                 return;
 297
 298         for (blk = gdp->bg_inode_table, j = 0;
 299              j < fs->inode_blocks_per_group; j++, blk++) {
 300                 if (blk >= ext2fs_blocks_count(fs->super))
 301                         break;
 302                 ext2fs_block_alloc_stats(fs, blk, -1);
 303                 ext2fs_mark_block_bitmap2(reserve_blocks, blk);
 304         }
 305 }
 306
 307 /*
 308  * This routine is shared by the online and offline resize routines.
 309  * All of the information which is adjusted in memory is done here.
 310  */
 311 errcode_t adjust_fs_info(ext2_filsys fs, ext2_filsys old_fs,
 312                          ext2fs_block_bitmap reserve_blocks, blk64_t new_size)
 313 {
 314         errcode_t       retval;
 315         blk64_t         overhead = 0;
 316         blk64_t         rem;
 317         blk64_t         blk, group_block;
 318         blk64_t         real_end;
 319         blk64_t         old_numblocks, numblocks, adjblocks;
 320         unsigned long   i, j, old_desc_blocks;
 321         unsigned int    meta_bg, meta_bg_size;
 322         int             has_super, csum_flag;
 323         unsigned long long new_inodes;  /* u64 to check for overflow */
 324         double          percent;
 325
 326         ext2fs_blocks_count_set(fs->super, new_size);
 327
 328 retry:
 329         fs->group_desc_count = ext2fs_div64_ceil(ext2fs_blocks_count(fs->super) -
 330                                        fs->super->s_first_data_block,
 331                                        EXT2_BLOCKS_PER_GROUP(fs->super));
 332         if (fs->group_desc_count == 0)
 333                 return EXT2_ET_TOOSMALL;
 334         fs->desc_blocks = ext2fs_div_ceil(fs->group_desc_count,
 335                                           EXT2_DESC_PER_BLOCK(fs->super));
 336
 337         /*
 338          * Overhead is the number of bookkeeping blocks per group.  It
 339          * includes the superblock backup, the group descriptor
 340          * backups, the inode bitmap, the block bitmap, and the inode
 341          * table.
 342          */
 343         overhead = (int) (2 + fs->inode_blocks_per_group);
 344
 345         if (ext2fs_bg_has_super(fs, fs->group_desc_count - 1))
 346                 overhead += 1 + fs->desc_blocks +
 347                         fs->super->s_reserved_gdt_blocks;
 348
 349         /*
 350          * See if the last group is big enough to support the
 351          * necessary data structures.  If not, we need to get rid of
 352          * it.
 353          */
 354         rem = (ext2fs_blocks_count(fs->super) - fs->super->s_first_data_block) %
 355                 fs->super->s_blocks_per_group;
 356         if ((fs->group_desc_count == 1) && rem && (rem < overhead))
 357                 return EXT2_ET_TOOSMALL;
 358         if ((fs->group_desc_count > 1) && rem && (rem < overhead+50)) {
 359                 ext2fs_blocks_count_set(fs->super,
 360                                         ext2fs_blocks_count(fs->super) - rem);
 361                 goto retry;
 362         }
 363         /*
 364          * Adjust the number of inodes
 365          */
 366         new_inodes =(unsigned long long) fs->super->s_inodes_per_group * fs->group_desc_count;
 367         if (new_inodes > ~0U) {
 368                 fprintf(stderr, _("inodes (%llu) must be less than %u"),
 369                                    new_inodes, ~0U);
 370                 return EXT2_ET_TOO_MANY_INODES;
 371         }
 372         fs->super->s_inodes_count = fs->super->s_inodes_per_group *
 373                 fs->group_desc_count;
 374
 375         /*
 376          * Adjust the number of free blocks
 377          */
 378         blk = ext2fs_blocks_count(old_fs->super);
 379         if (blk > ext2fs_blocks_count(fs->super))
 380                 ext2fs_free_blocks_count_set(fs->super,
 381                         ext2fs_free_blocks_count(fs->super) -
 382                         (blk - ext2fs_blocks_count(fs->super)));
 383         else
 384                 ext2fs_free_blocks_count_set(fs->super,
 385                         ext2fs_free_blocks_count(fs->super) +
 386                         (ext2fs_blocks_count(fs->super) - blk));
 387
 388         /*
 389          * Adjust the number of reserved blocks
 390          */
 391         percent = (ext2fs_r_blocks_count(old_fs->super) * 100.0) /
 392                 ext2fs_blocks_count(old_fs->super);
 393         ext2fs_r_blocks_count_set(fs->super,
 394                                   (percent * ext2fs_blocks_count(fs->super) /
 395                                    100.0));
 396
 397         /*
 398          * Adjust the bitmaps for size
 399          */
 400         retval = ext2fs_resize_inode_bitmap2(fs->super->s_inodes_count,
 401                                             fs->super->s_inodes_count,
 402                                             fs->inode_map);
 403         if (retval) goto errout;
 404
 405         real_end = (((blk64_t) EXT2_BLOCKS_PER_GROUP(fs->super) *
 406                      fs->group_desc_count)) - 1 +
 407                 fs->super->s_first_data_block;
 408         retval = ext2fs_resize_block_bitmap2(new_size - 1,
 409                                              real_end, fs->block_map);
 410         if (retval) goto errout;
 411
 412         /*
 413          * If we are growing the file system, also grow the size of
 414          * the reserve_blocks bitmap
 415          */
 416         if (reserve_blocks && new_size > ext2fs_blocks_count(old_fs->super)) {
 417                 retval = ext2fs_resize_block_bitmap2(new_size - 1,
 418                                                      real_end, reserve_blocks);
 419                 if (retval) goto errout;
 420         }
 421
 422         /*
 423          * Reallocate the group descriptors as necessary.
 424          */
 425         if (old_fs->desc_blocks != fs->desc_blocks) {
 426                 retval = ext2fs_resize_mem(old_fs->desc_blocks *
 427                                            fs->blocksize,
 428                                            fs->desc_blocks * fs->blocksize,
 429                                            &fs->group_desc);
 430                 if (retval)
 431                         goto errout;
 432                 if (fs->desc_blocks > old_fs->desc_blocks)
 433                         memset((char *) fs->group_desc +
 434                                (old_fs->desc_blocks * fs->blocksize), 0,
 435                                (fs->desc_blocks - old_fs->desc_blocks) *
 436                                fs->blocksize);
 437         }
 438
 439         /*
 440          * If the resize_inode feature is set, and we are changing the
 441          * number of descriptor blocks, then adjust
 442          * s_reserved_gdt_blocks if possible to avoid needing to move
 443          * the inode table either now or in the future.
 444          */
 445         if ((fs->super->s_feature_compat &
 446              EXT2_FEATURE_COMPAT_RESIZE_INODE) &&
 447             (old_fs->desc_blocks != fs->desc_blocks)) {
 448                 int new;
 449
 450                 new = ((int) fs->super->s_reserved_gdt_blocks) +
 451                         (old_fs->desc_blocks - fs->desc_blocks);
 452                 if (new < 0)
 453                         new = 0;
 454                 if (new > (int) fs->blocksize/4)
 455                         new = fs->blocksize/4;
 456                 fs->super->s_reserved_gdt_blocks = new;
 457         }
 458
 459         /*
 460          * If we are shrinking the number of block groups, we're done
 461          * and can exit now.
 462          */
 463         if (old_fs->group_desc_count > fs->group_desc_count) {
 464                 /*
 465                  * Check the block groups that we are chopping off
 466                  * and free any blocks associated with their metadata
 467                  */
 468                 for (i = fs->group_desc_count;
 469                      i < old_fs->group_desc_count; i++) {
 470                         free_gdp_blocks(fs, reserve_blocks,
 471                                         ext2fs_group_desc(old_fs,
 472                                                 old_fs->group_desc, i));
 473                 }
 474                 retval = 0;
 475                 goto errout;
 476         }
 477
 478         /*
 479          * Fix the count of the last (old) block group
 480          */
 481         old_numblocks = (ext2fs_blocks_count(old_fs->super) -
 482                          old_fs->super->s_first_data_block) %
 483                                  old_fs->super->s_blocks_per_group;
 484         if (!old_numblocks)
 485                 old_numblocks = old_fs->super->s_blocks_per_group;
 486         if (old_fs->group_desc_count == fs->group_desc_count) {
 487                 numblocks = (ext2fs_blocks_count(fs->super) -
 488                              fs->super->s_first_data_block) %
 489                         fs->super->s_blocks_per_group;
 490                 if (!numblocks)
 491                         numblocks = fs->super->s_blocks_per_group;
 492         } else
 493                 numblocks = fs->super->s_blocks_per_group;
 494         i = old_fs->group_desc_count - 1;
 495         ext2fs_bg_free_blocks_count_set(fs, i, ext2fs_bg_free_blocks_count(fs, i) + (numblocks - old_numblocks));
 496         ext2fs_group_desc_csum_set(fs, i);
 497
 498         /*
 499          * If the number of block groups is staying the same, we're
 500          * done and can exit now.  (If the number block groups is
 501          * shrinking, we had exited earlier.)
 502          */
 503         if (old_fs->group_desc_count >= fs->group_desc_count) {
 504                 retval = 0;
 505                 goto errout;
 506         }
 507
 508         /*
 509          * Initialize the new block group descriptors
 510          */
 511         group_block = ext2fs_group_first_block2(fs,
 512                                                 old_fs->group_desc_count);
 513         csum_flag = ext2fs_has_group_desc_csum(fs);
 514         if (access("/sys/fs/ext4/features/lazy_itable_init", F_OK) == 0)
 515                 lazy_itable_init = 1;
 516         if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
 517                 old_desc_blocks = fs->super->s_first_meta_bg;
 518         else
 519                 old_desc_blocks = fs->desc_blocks +
 520                         fs->super->s_reserved_gdt_blocks;
 521
 522         /*
 523          * If we changed the number of block_group descriptor blocks,
 524          * we need to make sure they are all marked as reserved in the
 525          * file systems's block allocation map.
 526          */
 527         for (i = 0; i < old_fs->group_desc_count; i++)
 528                 ext2fs_reserve_super_and_bgd(fs, i, fs->block_map);
 529
 530         for (i = old_fs->group_desc_count;
 531              i < fs->group_desc_count; i++) {
 532                 memset(ext2fs_group_desc(fs, fs->group_desc, i), 0,
 533                        sizeof(struct ext2_group_desc));
 534                 adjblocks = 0;
 535
 536                 ext2fs_bg_flags_zap(fs, i);
 537                 if (csum_flag) {
 538                         ext2fs_bg_flags_set(fs, i, EXT2_BG_INODE_UNINIT);
 539                         if (!lazy_itable_init)
 540                                 ext2fs_bg_flags_set(fs, i,
 541                                                     EXT2_BG_INODE_ZEROED);
 542                         ext2fs_bg_itable_unused_set(fs, i,
 543                                         fs->super->s_inodes_per_group);
 544                 }
 545
 546                 numblocks = ext2fs_group_blocks_count(fs, i);
 547                 if ((i < fs->group_desc_count - 1) && csum_flag)
 548                         ext2fs_bg_flags_set(fs, i, EXT2_BG_BLOCK_UNINIT);
 549
 550                 has_super = ext2fs_bg_has_super(fs, i);
 551                 if (has_super) {
 552                         ext2fs_block_alloc_stats2(fs, group_block, +1);
 553                         adjblocks++;
 554                 }
 555                 meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
 556                 meta_bg = i / meta_bg_size;
 557                 if (!(fs->super->s_feature_incompat &
 558                       EXT2_FEATURE_INCOMPAT_META_BG) ||
 559                     (meta_bg < fs->super->s_first_meta_bg)) {
 560                         if (has_super) {
 561                                 for (j=0; j < old_desc_blocks; j++)
 562                                         ext2fs_block_alloc_stats2(fs,
 563                                                  group_block + 1 + j, +1);
 564                                 adjblocks += old_desc_blocks;
 565                         }
 566                 } else {
 567                         if (has_super)
 568                                 has_super = 1;
 569                         if (((i % meta_bg_size) == 0) ||
 570                             ((i % meta_bg_size) == 1) ||
 571                             ((i % meta_bg_size) == (meta_bg_size-1)))
 572                                 ext2fs_block_alloc_stats2(fs,
 573                                                  group_block + has_super, +1);
 574                 }
 575
 576                 adjblocks += 2 + fs->inode_blocks_per_group;
 577
 578                 numblocks -= adjblocks;
 579                 ext2fs_free_blocks_count_set(fs->super,
 580                              ext2fs_free_blocks_count(fs->super) - adjblocks);
 581                 fs->super->s_free_inodes_count +=
 582                         fs->super->s_inodes_per_group;
 583                 ext2fs_bg_free_blocks_count_set(fs, i, numblocks);
 584                 ext2fs_bg_free_inodes_count_set(fs, i,
 585                                                 fs->super->s_inodes_per_group);
 586                 ext2fs_bg_used_dirs_count_set(fs, i, 0);
 587                 ext2fs_group_desc_csum_set(fs, i);
 588
 589                 retval = ext2fs_allocate_group_table(fs, i, 0);
 590                 if (retval) goto errout;
 591
 592                 group_block += fs->super->s_blocks_per_group;
 593         }
 594         retval = 0;
 595
 596         /*
 597          * Mark all of the metadata blocks as reserved so they won't
 598          * get allocated by the call to ext2fs_allocate_group_table()
 599          * in blocks_to_move(), where we allocate new blocks to
 600          * replace those allocation bitmap and inode table blocks
 601          * which have to get relocated to make space for an increased
 602          * number of the block group descriptors.
 603          */
 604         if (reserve_blocks)
 605                 mark_table_blocks(fs, reserve_blocks);
 606
 607 errout:
 608         return (retval);
 609 }
 610
 611 /*
 612  * This routine adjusts the superblock and other data structures, both
 613  * in disk as well as in memory...
 614  */
 615 static errcode_t adjust_superblock(ext2_resize_t rfs, blk64_t new_size)
 616 {
 617         ext2_filsys fs;
 618         int             adj = 0;
 619         errcode_t       retval;
 620         blk64_t         group_block;
 621         unsigned long   i;
 622         unsigned long   max_group;
 623
 624         fs = rfs->new_fs;
 625         ext2fs_mark_super_dirty(fs);
 626         ext2fs_mark_bb_dirty(fs);
 627         ext2fs_mark_ib_dirty(fs);
 628
 629         retval = ext2fs_allocate_block_bitmap(fs, _("reserved blocks"),
 630                                               &rfs->reserve_blocks);
 631         if (retval)
 632                 return retval;
 633
 634         retval = adjust_fs_info(fs, rfs->old_fs, rfs->reserve_blocks, new_size);
 635         if (retval)
 636                 goto errout;
 637
 638         /*
 639          * Check to make sure there are enough inodes
 640          */
 641         if ((rfs->old_fs->super->s_inodes_count -
 642              rfs->old_fs->super->s_free_inodes_count) >
 643             rfs->new_fs->super->s_inodes_count) {
 644                 retval = ENOSPC;
 645                 goto errout;
 646         }
 647
 648         /*
 649          * If we are shrinking the number block groups, we're done and
 650          * can exit now.
 651          */
 652         if (rfs->old_fs->group_desc_count > fs->group_desc_count) {
 653                 retval = 0;
 654                 goto errout;
 655         }
 656
 657         /*
 658          * If the number of block groups is staying the same, we're
 659          * done and can exit now.  (If the number block groups is
 660          * shrinking, we had exited earlier.)
 661          */
 662         if (rfs->old_fs->group_desc_count >= fs->group_desc_count) {
 663                 retval = 0;
 664                 goto errout;
 665         }
 666
 667         /*
 668          * If we are using uninit_bg (aka GDT_CSUM) and the kernel
 669          * supports lazy inode initialization, we can skip
 670          * initializing the inode table.
 671          */
 672         if (lazy_itable_init &&
 673             EXT2_HAS_RO_COMPAT_FEATURE(fs->super,
 674                                        EXT4_FEATURE_RO_COMPAT_GDT_CSUM)) {
 675                 retval = 0;
 676                 goto errout;
 677         }
 678
 679         /*
 680          * Initialize the inode table
 681          */
 682         retval = ext2fs_get_array(fs->blocksize, fs->inode_blocks_per_group,
 683                                 &rfs->itable_buf);
 684         if (retval)
 685                 goto errout;
 686
 687         memset(rfs->itable_buf, 0, fs->blocksize * fs->inode_blocks_per_group);
 688         group_block = ext2fs_group_first_block2(fs,
 689                                                 rfs->old_fs->group_desc_count);
 690         adj = rfs->old_fs->group_desc_count;
 691         max_group = fs->group_desc_count - adj;
 692         if (rfs->progress) {
 693                 retval = rfs->progress(rfs, E2_RSZ_EXTEND_ITABLE_PASS,
 694                                        0, max_group);
 695                 if (retval)
 696                         goto errout;
 697         }
 698         for (i = rfs->old_fs->group_desc_count;
 699              i < fs->group_desc_count; i++) {
 700                 /*
 701                  * Write out the new inode table
 702                  */
 703                 retval = io_channel_write_blk64(fs->io,
 704                                                 ext2fs_inode_table_loc(fs, i),
 705                                                 fs->inode_blocks_per_group,
 706                                                 rfs->itable_buf);
 707                 if (retval) goto errout;
 708
 709                 io_channel_flush(fs->io);
 710                 if (rfs->progress) {
 711                         retval = rfs->progress(rfs, E2_RSZ_EXTEND_ITABLE_PASS,
 712                                                i - adj + 1, max_group);
 713                         if (retval)
 714                                 goto errout;
 715                 }
 716                 group_block += fs->super->s_blocks_per_group;
 717         }
 718         io_channel_flush(fs->io);
 719         retval = 0;
 720
 721 errout:
 722         return retval;
 723 }
 724
 725 /* --------------------------------------------------------------------
 726  *
 727  * Resize processing, phase 2.
 728  *
 729  * In this phase we adjust determine which blocks need to be moved, in
 730  * blocks_to_move().  We then copy the blocks to their ultimate new
 731  * destinations using block_mover().  Since we are copying blocks to
 732  * their new locations, again during this pass we can abort without
 733  * any problems.
 734  * --------------------------------------------------------------------
 735  */
 736
 737 /*
 738  * This helper function creates a block bitmap with all of the
 739  * filesystem meta-data blocks.
 740  */
 741 static errcode_t mark_table_blocks(ext2_filsys fs,
 742                                    ext2fs_block_bitmap bmap)
 743 {
 744         dgrp_t                  i;
 745         blk64_t                 blk;
 746
 747         for (i = 0; i < fs->group_desc_count; i++) {
 748                 ext2fs_reserve_super_and_bgd(fs, i, bmap);
 749
 750                 /*
 751                  * Mark the blocks used for the inode table
 752                  */
 753                 blk = ext2fs_inode_table_loc(fs, i);
 754                 if (blk)
 755                         ext2fs_mark_block_bitmap_range2(bmap, blk,
 756                                                 fs->inode_blocks_per_group);
 757
 758                 /*
 759                  * Mark block used for the block bitmap
 760                  */
 761                 blk = ext2fs_block_bitmap_loc(fs, i);
 762                 if (blk)
 763                         ext2fs_mark_block_bitmap2(bmap, blk);
 764
 765                 /*
 766                  * Mark block used for the inode bitmap
 767                  */
 768                 blk = ext2fs_inode_bitmap_loc(fs, i);
 769                 if (blk)
 770                         ext2fs_mark_block_bitmap2(bmap, blk);
 771         }
 772         return 0;
 773 }
 774
 775 /*
 776  * This function checks to see if a particular block (either a
 777  * superblock or a block group descriptor) overlaps with an inode or
 778  * block bitmap block, or with the inode table.
 779  */
 780 static void mark_fs_metablock(ext2_resize_t rfs,
 781                               ext2fs_block_bitmap meta_bmap,
 782                               int group, blk64_t blk)
 783 {
 784         ext2_filsys     fs = rfs->new_fs;
 785
 786         ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
 787         ext2fs_block_alloc_stats2(fs, blk, +1);
 788
 789         /*
 790          * Check to see if we overlap with the inode or block bitmap,
 791          * or the inode tables.  If not, and the block is in use, then
 792          * mark it as a block to be moved.
 793          */
 794         if (IS_BLOCK_BM(fs, group, blk)) {
 795                 ext2fs_block_bitmap_loc_set(fs, group, 0);
 796                 rfs->needed_blocks++;
 797                 return;
 798         }
 799         if (IS_INODE_BM(fs, group, blk)) {
 800                 ext2fs_inode_bitmap_loc_set(fs, group, 0);
 801                 rfs->needed_blocks++;
 802                 return;
 803         }
 804         if (IS_INODE_TB(fs, group, blk)) {
 805                 ext2fs_inode_table_loc_set(fs, group, 0);
 806                 rfs->needed_blocks++;
 807                 return;
 808         }
 809         if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_FLEX_BG) {
 810                 dgrp_t i;
 811
 812                 for (i=0; i < rfs->old_fs->group_desc_count; i++) {
 813                         if (IS_BLOCK_BM(fs, i, blk)) {
 814                                 ext2fs_block_bitmap_loc_set(fs, i, 0);
 815                                 rfs->needed_blocks++;
 816                                 return;
 817                         }
 818                         if (IS_INODE_BM(fs, i, blk)) {
 819                                 ext2fs_inode_bitmap_loc_set(fs, i, 0);
 820                                 rfs->needed_blocks++;
 821                                 return;
 822                         }
 823                         if (IS_INODE_TB(fs, i, blk)) {
 824                                 ext2fs_inode_table_loc_set(fs, i, 0);
 825                                 rfs->needed_blocks++;
 826                                 return;
 827                         }
 828                 }
 829         }
 830
 831         if (ext2fs_has_group_desc_csum(fs) &&
 832             (ext2fs_bg_flags_test(fs, group, EXT2_BG_BLOCK_UNINIT))) {
 833                 /*
 834                  * If the block bitmap is uninitialized, which means
 835                  * nothing other than standard metadata in use.
 836                  */
 837                 return;
 838         } else if (ext2fs_test_block_bitmap2(rfs->old_fs->block_map, blk) &&
 839                    !ext2fs_test_block_bitmap2(meta_bmap, blk)) {
 840                 ext2fs_mark_block_bitmap2(rfs->move_blocks, blk);
 841                 rfs->needed_blocks++;
 842         }
 843 }
 844
 845
 846 /*
 847  * This routine marks and unmarks reserved blocks in the new block
 848  * bitmap.  It also determines which blocks need to be moved and
 849  * places this information into the move_blocks bitmap.
 850  */
 851 static errcode_t blocks_to_move(ext2_resize_t rfs)
 852 {
 853         int             j, has_super;
 854         dgrp_t          i, max_groups, g;
 855         blk64_t         blk, group_blk;
 856         blk64_t         old_blocks, new_blocks;
 857         unsigned int    meta_bg, meta_bg_size;
 858         errcode_t       retval;
 859         ext2_filsys     fs, old_fs;
 860         ext2fs_block_bitmap     meta_bmap;
 861         int             flex_bg;
 862
 863         fs = rfs->new_fs;
 864         old_fs = rfs->old_fs;
 865         if (ext2fs_blocks_count(old_fs->super) > ext2fs_blocks_count(fs->super))
 866                 fs = rfs->old_fs;
 867
 868         retval = ext2fs_allocate_block_bitmap(fs, _("blocks to be moved"),
 869                                               &rfs->move_blocks);
 870         if (retval)
 871                 return retval;
 872
 873         retval = ext2fs_allocate_block_bitmap(fs, _("meta-data blocks"),
 874                                               &meta_bmap);
 875         if (retval)
 876                 return retval;
 877
 878         retval = mark_table_blocks(old_fs, meta_bmap);
 879         if (retval)
 880                 return retval;
 881
 882         fs = rfs->new_fs;
 883
 884         /*
 885          * If we're shrinking the filesystem, we need to move all of
 886          * the blocks that don't fit any more
 887          */
 888         for (blk = ext2fs_blocks_count(fs->super);
 889              blk < ext2fs_blocks_count(old_fs->super); blk++) {
 890                 g = ext2fs_group_of_blk2(fs, blk);
 891                 if (ext2fs_has_group_desc_csum(fs) &&
 892                     ext2fs_bg_flags_test(old_fs, g, EXT2_BG_BLOCK_UNINIT)) {
 893                         /*
 894                          * The block bitmap is uninitialized, so skip
 895                          * to the next block group.
 896                          */
 897                         blk = ext2fs_group_first_block2(fs, g+1) - 1;
 898                         continue;
 899                 }
 900                 if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
 901                     !ext2fs_test_block_bitmap2(meta_bmap, blk)) {
 902                         ext2fs_mark_block_bitmap2(rfs->move_blocks, blk);
 903                         rfs->needed_blocks++;
 904                 }
 905                 ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
 906         }
 907
 908         if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG) {
 909                 old_blocks = old_fs->super->s_first_meta_bg;
 910                 new_blocks = fs->super->s_first_meta_bg;
 911         } else {
 912                 old_blocks = old_fs->desc_blocks + old_fs->super->s_reserved_gdt_blocks;
 913                 new_blocks = fs->desc_blocks + fs->super->s_reserved_gdt_blocks;
 914         }
 915
 916         if (old_blocks == new_blocks) {
 917                 retval = 0;
 918                 goto errout;
 919         }
 920
 921         max_groups = fs->group_desc_count;
 922         if (max_groups > old_fs->group_desc_count)
 923                 max_groups = old_fs->group_desc_count;
 924         group_blk = old_fs->super->s_first_data_block;
 925         /*
 926          * If we're reducing the number of descriptor blocks, this
 927          * makes life easy.  :-)   We just have to mark some extra
 928          * blocks as free.
 929          */
 930         if (old_blocks > new_blocks) {
 931                 for (i = 0; i < max_groups; i++) {
 932                         if (!ext2fs_bg_has_super(fs, i)) {
 933                                 group_blk += fs->super->s_blocks_per_group;
 934                                 continue;
 935                         }
 936                         for (blk = group_blk+1+new_blocks;
 937                              blk < group_blk+1+old_blocks; blk++) {
 938                                 ext2fs_block_alloc_stats2(fs, blk, -1);
 939                                 rfs->needed_blocks--;
 940                         }
 941                         group_blk += fs->super->s_blocks_per_group;
 942                 }
 943                 retval = 0;
 944                 goto errout;
 945         }
 946         /*
 947          * If we're increasing the number of descriptor blocks, life
 948          * gets interesting....
 949          */
 950         meta_bg_size = EXT2_DESC_PER_BLOCK(fs->super);
 951         flex_bg = fs->super->s_feature_incompat &
 952                 EXT4_FEATURE_INCOMPAT_FLEX_BG;
 953         /* first reserve all of the existing fs meta blocks */
 954         for (i = 0; i < max_groups; i++) {
 955                 has_super = ext2fs_bg_has_super(fs, i);
 956                 if (has_super)
 957                         mark_fs_metablock(rfs, meta_bmap, i, group_blk);
 958
 959                 meta_bg = i / meta_bg_size;
 960                 if (!(fs->super->s_feature_incompat &
 961                       EXT2_FEATURE_INCOMPAT_META_BG) ||
 962                     (meta_bg < fs->super->s_first_meta_bg)) {
 963                         if (has_super) {
 964                                 for (blk = group_blk+1;
 965                                      blk < group_blk + 1 + new_blocks; blk++)
 966                                         mark_fs_metablock(rfs, meta_bmap,
 967                                                           i, blk);
 968                         }
 969                 } else {
 970                         if (has_super)
 971                                 has_super = 1;
 972                         if (((i % meta_bg_size) == 0) ||
 973                             ((i % meta_bg_size) == 1) ||
 974                             ((i % meta_bg_size) == (meta_bg_size-1)))
 975                                 mark_fs_metablock(rfs, meta_bmap, i,
 976                                                   group_blk + has_super);
 977                 }
 978
 979                 /*
 980                  * Reserve the existing meta blocks that we know
 981                  * aren't to be moved.
 982                  *
 983                  * For flex_bg file systems, in order to avoid
 984                  * overwriting fs metadata (especially inode table
 985                  * blocks) belonging to a different block group when
 986                  * we are relocating the inode tables, we need to
 987                  * reserve all existing fs metadata blocks.
 988                  */
 989                 if (ext2fs_block_bitmap_loc(fs, i))
 990                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
 991                                  ext2fs_block_bitmap_loc(fs, i));
 992                 else if (flex_bg && i < old_fs->group_desc_count)
 993                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
 994                                  ext2fs_block_bitmap_loc(old_fs, i));
 995
 996                 if (ext2fs_inode_bitmap_loc(fs, i))
 997                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
 998                                  ext2fs_inode_bitmap_loc(fs, i));
 999                 else if (flex_bg && i < old_fs->group_desc_count)
1000                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks,
1001                                  ext2fs_inode_bitmap_loc(old_fs, i));
1002
1003                 if (ext2fs_inode_table_loc(fs, i))
1004                         ext2fs_mark_block_bitmap_range2(rfs->reserve_blocks,
1005                                         ext2fs_inode_table_loc(fs, i),
1006                                         fs->inode_blocks_per_group);
1007                 else if (flex_bg && i < old_fs->group_desc_count)
1008                         ext2fs_mark_block_bitmap_range2(rfs->reserve_blocks,
1009                                         ext2fs_inode_table_loc(old_fs, i),
1010                                         old_fs->inode_blocks_per_group);
1011
1012                 group_blk += rfs->new_fs->super->s_blocks_per_group;
1013         }
1014
1015         /* Allocate the missing data structures */
1016         for (i = 0; i < max_groups; i++) {
1017                 if (ext2fs_inode_table_loc(fs, i) &&
1018                     ext2fs_inode_bitmap_loc(fs, i) &&
1019                     ext2fs_block_bitmap_loc(fs, i))
1020                         continue;
1021
1022                 retval = ext2fs_allocate_group_table(fs, i,
1023                                                      rfs->reserve_blocks);
1024                 if (retval)
1025                         goto errout;
1026
1027                 /*
1028                  * For those structures that have changed, we need to
1029                  * do bookkeepping.
1030                  */
1031                 if (ext2fs_block_bitmap_loc(old_fs, i) !=
1032                     (blk = ext2fs_block_bitmap_loc(fs, i))) {
1033                         ext2fs_block_alloc_stats2(fs, blk, +1);
1034                         if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
1035                             !ext2fs_test_block_bitmap2(meta_bmap, blk))
1036                                 ext2fs_mark_block_bitmap2(rfs->move_blocks,
1037                                                          blk);
1038                 }
1039                 if (ext2fs_inode_bitmap_loc(old_fs, i) !=
1040                     (blk = ext2fs_inode_bitmap_loc(fs, i))) {
1041                         ext2fs_block_alloc_stats2(fs, blk, +1);
1042                         if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
1043                             !ext2fs_test_block_bitmap2(meta_bmap, blk))
1044                                 ext2fs_mark_block_bitmap2(rfs->move_blocks,
1045                                                          blk);
1046                 }
1047
1048                 /*
1049                  * The inode table, if we need to relocate it, is
1050                  * handled specially.  We have to reserve the blocks
1051                  * for both the old and the new inode table, since we
1052                  * can't have the inode table be destroyed during the
1053                  * block relocation phase.
1054                  */
1055                 if (ext2fs_inode_table_loc(fs, i) == ext2fs_inode_table_loc(old_fs, i))
1056                         continue;       /* inode table not moved */
1057
1058                 rfs->needed_blocks += fs->inode_blocks_per_group;
1059
1060                 /*
1061                  * Mark the new inode table as in use in the new block
1062                  * allocation bitmap, and move any blocks that might
1063                  * be necessary.
1064                  */
1065                 for (blk = ext2fs_inode_table_loc(fs, i), j=0;
1066                      j < fs->inode_blocks_per_group ; j++, blk++) {
1067                         ext2fs_block_alloc_stats2(fs, blk, +1);
1068                         if (ext2fs_test_block_bitmap2(old_fs->block_map, blk) &&
1069                             !ext2fs_test_block_bitmap2(meta_bmap, blk))
1070                                 ext2fs_mark_block_bitmap2(rfs->move_blocks,
1071                                                          blk);
1072                 }
1073
1074                 /*
1075                  * Make sure the old inode table is reserved in the
1076                  * block reservation bitmap.
1077                  */
1078                 for (blk = ext2fs_inode_table_loc(rfs->old_fs, i), j=0;
1079                      j < fs->inode_blocks_per_group ; j++, blk++)
1080                         ext2fs_mark_block_bitmap2(rfs->reserve_blocks, blk);
1081         }
1082         retval = 0;
1083
1084 errout:
1085         if (meta_bmap)
1086                 ext2fs_free_block_bitmap(meta_bmap);
1087
1088         return retval;
1089 }
1090
1091 /*
1092  * This helper function tries to allocate a new block.  We try to
1093  * avoid hitting the original group descriptor blocks at least at
1094  * first, since we want to make it possible to recover from a badly
1095  * aborted resize operation as much as possible.
1096  *
1097  * In the future, I may further modify this routine to balance out
1098  * where we get the new blocks across the various block groups.
1099  * Ideally we would allocate blocks that corresponded with the block
1100  * group of the containing inode, and keep contiguous blocks
1101  * together.  However, this very difficult to do efficiently, since we
1102  * don't have the necessary information up front.
1103  */
1104
1105 #define AVOID_OLD       1
1106 #define DESPERATION     2
1107
1108 static void init_block_alloc(ext2_resize_t rfs)
1109 {
1110         rfs->alloc_state = AVOID_OLD;
1111         rfs->new_blk = rfs->new_fs->super->s_first_data_block;
1112 #if 0
1113         /* HACK for testing */
1114         if (ext2fs_blocks_count(rfs->new_fs->super) >
1115             ext2fs_blocks_count(rfs->old_fs->super))
1116                 rfs->new_blk = ext2fs_blocks_count(rfs->old_fs->super);
1117 #endif
1118 }
1119
1120 static blk64_t get_new_block(ext2_resize_t rfs)
1121 {
1122         ext2_filsys     fs = rfs->new_fs;
1123
1124         while (1) {
1125                 if (rfs->new_blk >= ext2fs_blocks_count(fs->super)) {
1126                         if (rfs->alloc_state == DESPERATION)
1127                                 return 0;
1128
1129 #ifdef RESIZE2FS_DEBUG
1130                         if (rfs->flags & RESIZE_DEBUG_BMOVE)
1131                                 printf("Going into desperation mode "
1132                                        "for block allocations\n");
1133 #endif
1134                         rfs->alloc_state = DESPERATION;
1135                         rfs->new_blk = fs->super->s_first_data_block;
1136                         continue;
1137                 }
1138                 if (ext2fs_test_block_bitmap2(fs->block_map, rfs->new_blk) ||
1139                     ext2fs_test_block_bitmap2(rfs->reserve_blocks,
1140                                              rfs->new_blk) ||
1141                     ((rfs->alloc_state == AVOID_OLD) &&
1142                      (rfs->new_blk < ext2fs_blocks_count(rfs->old_fs->super)) &&
1143                      ext2fs_test_block_bitmap2(rfs->old_fs->block_map,
1144                                               rfs->new_blk))) {
1145                         rfs->new_blk++;
1146                         continue;
1147                 }
1148                 return rfs->new_blk;
1149         }
1150 }
1151
1152 static errcode_t resize2fs_get_alloc_block(ext2_filsys fs, blk64_t goal,
1153                                            blk64_t *ret)
1154 {
1155         ext2_resize_t rfs = (ext2_resize_t) fs->priv_data;
1156         blk64_t blk;
1157
1158         blk = get_new_block(rfs);
1159         if (!blk)
1160                 return ENOSPC;
1161
1162 #ifdef RESIZE2FS_DEBUG
1163         if (rfs->flags & 0xF)
1164                 printf("get_alloc_block allocating %llu\n", blk);
1165 #endif
1166
1167         ext2fs_mark_block_bitmap2(rfs->old_fs->block_map, blk);
1168         ext2fs_mark_block_bitmap2(rfs->new_fs->block_map, blk);
1169         *ret = (blk64_t) blk;
1170         return 0;
1171 }
1172
1173 static errcode_t block_mover(ext2_resize_t rfs)
1174 {
1175         blk64_t                 blk, old_blk, new_blk;
1176         ext2_filsys             fs = rfs->new_fs;
1177         ext2_filsys             old_fs = rfs->old_fs;
1178         errcode_t               retval;
1179         __u64                   size;
1180         int                     c;
1181         int                     to_move, moved;
1182         ext2_badblocks_list     badblock_list = 0;
1183         int                     bb_modified = 0;
1184
1185         fs->get_alloc_block = resize2fs_get_alloc_block;
1186         old_fs->get_alloc_block = resize2fs_get_alloc_block;
1187
1188         retval = ext2fs_read_bb_inode(old_fs, &badblock_list);
1189         if (retval)
1190                 return retval;
1191
1192         new_blk = fs->super->s_first_data_block;
1193         if (!rfs->itable_buf) {
1194                 retval = ext2fs_get_array(fs->blocksize,
1195                                         fs->inode_blocks_per_group,
1196                                         &rfs->itable_buf);
1197                 if (retval)
1198                         return retval;
1199         }
1200         retval = ext2fs_create_extent_table(&rfs->bmap, 0);
1201         if (retval)
1202                 return retval;
1203
1204         /*
1205          * The first step is to figure out where all of the blocks
1206          * will go.
1207          */
1208         to_move = moved = 0;
1209         init_block_alloc(rfs);
1210         for (blk = B2C(old_fs->super->s_first_data_block);
1211              blk < ext2fs_blocks_count(old_fs->super);
1212              blk += EXT2FS_CLUSTER_RATIO(fs)) {
1213                 if (!ext2fs_test_block_bitmap2(old_fs->block_map, blk))
1214                         continue;
1215                 if (!ext2fs_test_block_bitmap2(rfs->move_blocks, blk))
1216                         continue;
1217                 if (ext2fs_badblocks_list_test(badblock_list, blk)) {
1218                         ext2fs_badblocks_list_del(badblock_list, blk);
1219                         bb_modified++;
1220                         continue;
1221                 }
1222
1223                 new_blk = get_new_block(rfs);
1224                 if (!new_blk) {
1225                         retval = ENOSPC;
1226                         goto errout;
1227                 }
1228                 ext2fs_block_alloc_stats2(fs, new_blk, +1);
1229                 ext2fs_add_extent_entry(rfs->bmap, B2C(blk), B2C(new_blk));
1230                 to_move++;
1231         }
1232
1233         if (to_move == 0) {
1234                 if (rfs->bmap) {
1235                         ext2fs_free_extent_table(rfs->bmap);
1236                         rfs->bmap = 0;
1237                 }
1238                 retval = 0;
1239                 goto errout;
1240         }
1241
1242         /*
1243          * Step two is to actually move the blocks
1244          */
1245         retval =  ext2fs_iterate_extent(rfs->bmap, 0, 0, 0);
1246         if (retval) goto errout;
1247
1248         if (rfs->progress) {
1249                 retval = (rfs->progress)(rfs, E2_RSZ_BLOCK_RELOC_PASS,
1250                                          0, to_move);
1251                 if (retval)
1252                         goto errout;
1253         }
1254         while (1) {
1255                 retval = ext2fs_iterate_extent(rfs->bmap, &old_blk, &new_blk, &size);
1256                 if (retval) goto errout;
1257                 if (!size)
1258                         break;
1259                 old_blk = C2B(old_blk);
1260                 new_blk = C2B(new_blk);
1261                 size = C2B(size);
1262 #ifdef RESIZE2FS_DEBUG
1263                 if (rfs->flags & RESIZE_DEBUG_BMOVE)
1264                         printf("Moving %llu blocks %llu->%llu\n",
1265                                size, old_blk, new_blk);
1266 #endif
1267                 do {
1268                         c = size;
1269                         if (c > fs->inode_blocks_per_group)
1270                                 c = fs->inode_blocks_per_group;
1271                         retval = io_channel_read_blk64(fs->io, old_blk, c,
1272                                                        rfs->itable_buf);
1273                         if (retval) goto errout;
1274                         retval = io_channel_write_blk64(fs->io, new_blk, c,
1275                                                         rfs->itable_buf);
1276                         if (retval) goto errout;
1277                         size -= c;
1278                         new_blk += c;
1279                         old_blk += c;
1280                         moved += c;
1281                         if (rfs->progress) {
1282                                 io_channel_flush(fs->io);
1283                                 retval = (rfs->progress)(rfs,
1284                                                 E2_RSZ_BLOCK_RELOC_PASS,
1285                                                 moved, to_move);
1286                                 if (retval)
1287                                         goto errout;
1288                         }
1289                 } while (size > 0);
1290                 io_channel_flush(fs->io);
1291         }
1292
1293 errout:
1294         if (badblock_list) {
1295                 if (!retval && bb_modified)
1296                         retval = ext2fs_update_bb_inode(old_fs,
1297                                                         badblock_list);
1298                 ext2fs_badblocks_list_free(badblock_list);
1299         }
1300         return retval;
1301 }
1302
1303
1304 /* --------------------------------------------------------------------
1305  *
1306  * Resize processing, phase 3
1307  *
1308  * --------------------------------------------------------------------
1309  */
1310
1311
1312 /*
1313  * The extent translation table is stored in clusters so we need to
1314  * take special care when mapping a source block number to its
1315  * destination block number.
1316  */
1317 __u64 extent_translate(ext2_filsys fs, ext2_extent extent, __u64 old_loc)
1318 {
1319         __u64 new_block = C2B(ext2fs_extent_translate(extent, B2C(old_loc)));
1320
1321         if (new_block != 0)
1322                 new_block += old_loc & (EXT2FS_CLUSTER_RATIO(fs) - 1);
1323         return new_block;
1324 }
1325
1326 struct process_block_struct {
1327         ext2_resize_t           rfs;
1328         ext2_ino_t              ino;
1329         struct ext2_inode *     inode;
1330         errcode_t               error;
1331         int                     is_dir;
1332         int                     changed;
1333 };
1334
1335 static int process_block(ext2_filsys fs, blk64_t        *block_nr,
1336                          e2_blkcnt_t blockcnt,
1337                          blk64_t ref_block EXT2FS_ATTR((unused)),
1338                          int ref_offset EXT2FS_ATTR((unused)), void *priv_data)
1339 {
1340         struct process_block_struct *pb;
1341         errcode_t       retval;
1342         blk64_t         block, new_block;
1343         int             ret = 0;
1344
1345         pb = (struct process_block_struct *) priv_data;
1346         block = *block_nr;
1347         if (pb->rfs->bmap) {
1348                 new_block = extent_translate(fs, pb->rfs->bmap, block);
1349                 if (new_block) {
1350                         *block_nr = new_block;
1351                         ret |= BLOCK_CHANGED;
1352                         pb->changed = 1;
1353 #ifdef RESIZE2FS_DEBUG
1354                         if (pb->rfs->flags & RESIZE_DEBUG_BMOVE)
1355                                 printf("ino=%u, blockcnt=%lld, %llu->%llu\n",
1356                                        pb->ino, blockcnt, block, new_block);
1357 #endif
1358                         block = new_block;
1359                 }
1360         }
1361         if (pb->is_dir) {
1362                 retval = ext2fs_add_dir_block2(fs->dblist, pb->ino,
1363                                                block, (int) blockcnt);
1364                 if (retval) {
1365                         pb->error = retval;
1366                         ret |= BLOCK_ABORT;
1367                 }
1368         }
1369         return ret;
1370 }
1371
1372 /*
1373  * Progress callback
1374  */
1375 static errcode_t progress_callback(ext2_filsys fs,
1376                                    ext2_inode_scan scan EXT2FS_ATTR((unused)),
1377                                    dgrp_t group, void * priv_data)
1378 {
1379         ext2_resize_t rfs = (ext2_resize_t) priv_data;
1380         errcode_t               retval;
1381
1382         /*
1383          * This check is to protect against old ext2 libraries.  It
1384          * shouldn't be needed against new libraries.
1385          */
1386         if ((group+1) == 0)
1387                 return 0;
1388
1389         if (rfs->progress) {
1390                 io_channel_flush(fs->io);
1391                 retval = (rfs->progress)(rfs, E2_RSZ_INODE_SCAN_PASS,
1392                                          group+1, fs->group_desc_count);
1393                 if (retval)
1394                         return retval;
1395         }
1396
1397         return 0;
1398 }
1399
1400 static errcode_t inode_scan_and_fix(ext2_resize_t rfs)
1401 {
1402         struct process_block_struct     pb;
1403         ext2_ino_t              ino, new_inode;
1404         struct ext2_inode       *inode = NULL;
1405         ext2_inode_scan         scan = NULL;
1406         errcode_t               retval;
1407         char                    *block_buf = 0;
1408         ext2_ino_t              start_to_move;
1409         blk64_t                 orig_size;
1410         blk64_t                 new_block;
1411         int                     inode_size;
1412
1413         if ((rfs->old_fs->group_desc_count <=
1414              rfs->new_fs->group_desc_count) &&
1415             !rfs->bmap)
1416                 return 0;
1417
1418         /*
1419          * Save the original size of the old filesystem, and
1420          * temporarily set the size to be the new size if the new size
1421          * is larger.  We need to do this to avoid catching an error
1422          * by the block iterator routines
1423          */
1424         orig_size = ext2fs_blocks_count(rfs->old_fs->super);
1425         if (orig_size < ext2fs_blocks_count(rfs->new_fs->super))
1426                 ext2fs_blocks_count_set(rfs->old_fs->super,
1427                                 ext2fs_blocks_count(rfs->new_fs->super));
1428
1429         retval = ext2fs_open_inode_scan(rfs->old_fs, 0, &scan);
1430         if (retval) goto errout;
1431
1432         retval = ext2fs_init_dblist(rfs->old_fs, 0);
1433         if (retval) goto errout;
1434         retval = ext2fs_get_array(rfs->old_fs->blocksize, 3, &block_buf);
1435         if (retval) goto errout;
1436
1437         start_to_move = (rfs->new_fs->group_desc_count *
1438                          rfs->new_fs->super->s_inodes_per_group);
1439
1440         if (rfs->progress) {
1441                 retval = (rfs->progress)(rfs, E2_RSZ_INODE_SCAN_PASS,
1442                                          0, rfs->old_fs->group_desc_count);
1443                 if (retval)
1444                         goto errout;
1445         }
1446         ext2fs_set_inode_callback(scan, progress_callback, (void *) rfs);
1447         pb.rfs = rfs;
1448         pb.inode = inode;
1449         pb.error = 0;
1450         new_inode = EXT2_FIRST_INODE(rfs->new_fs->super);
1451         inode_size = EXT2_INODE_SIZE(rfs->new_fs->super);
1452         inode = malloc(inode_size);
1453         if (!inode) {
1454                 retval = ENOMEM;
1455                 goto errout;
1456         }
1457         /*
1458          * First, copy all of the inodes that need to be moved
1459          * elsewhere in the inode table
1460          */
1461         while (1) {
1462                 retval = ext2fs_get_next_inode_full(scan, &ino, inode, inode_size);
1463                 if (retval) goto errout;
1464                 if (!ino)
1465                         break;
1466
1467                 if (inode->i_links_count == 0 && ino != EXT2_RESIZE_INO)
1468                         continue; /* inode not in use */
1469
1470                 pb.is_dir = LINUX_S_ISDIR(inode->i_mode);
1471                 pb.changed = 0;
1472
1473                 if (ext2fs_file_acl_block(rfs->old_fs, inode) && rfs->bmap) {
1474                         new_block = extent_translate(rfs->old_fs, rfs->bmap,
1475                                 ext2fs_file_acl_block(rfs->old_fs, inode));
1476                         if (new_block) {
1477                                 ext2fs_file_acl_block_set(rfs->old_fs, inode,
1478                                                           new_block);
1479                                 retval = ext2fs_write_inode_full(rfs->old_fs,
1480                                                             ino, inode, inode_size);
1481                                 if (retval) goto errout;
1482                         }
1483                 }
1484
1485                 if (ext2fs_inode_has_valid_blocks2(rfs->old_fs, inode) &&
1486                     (rfs->bmap || pb.is_dir)) {
1487                         pb.ino = ino;
1488                         retval = ext2fs_block_iterate3(rfs->old_fs,
1489                                                        ino, 0, block_buf,
1490                                                        process_block, &pb);
1491                         if (retval)
1492                                 goto errout;
1493                         if (pb.error) {
1494                                 retval = pb.error;
1495                                 goto errout;
1496                         }
1497                 }
1498
1499                 if (ino <= start_to_move)
1500                         continue; /* Don't need to move it. */
1501
1502                 /*
1503                  * Find a new inode
1504                  */
1505                 retval = ext2fs_new_inode(rfs->new_fs, 0, 0, 0, &new_inode);
1506                 if (retval)
1507                         goto errout;
1508
1509                 ext2fs_inode_alloc_stats2(rfs->new_fs, new_inode, +1,
1510                                           pb.is_dir);
1511                 if (pb.changed) {
1512                         /* Get the new version of the inode */
1513                         retval = ext2fs_read_inode_full(rfs->old_fs, ino,
1514                                                 inode, inode_size);
1515                         if (retval) goto errout;
1516                 }
1517                 inode->i_ctime = time(0);
1518                 retval = ext2fs_write_inode_full(rfs->old_fs, new_inode,
1519                                                 inode, inode_size);
1520                 if (retval) goto errout;
1521
1522 #ifdef RESIZE2FS_DEBUG
1523                 if (rfs->flags & RESIZE_DEBUG_INODEMAP)
1524                         printf("Inode moved %u->%u\n", ino, new_inode);
1525 #endif
1526                 if (!rfs->imap) {
1527                         retval = ext2fs_create_extent_table(&rfs->imap, 0);
1528                         if (retval)
1529                                 goto errout;
1530                 }
1531                 ext2fs_add_extent_entry(rfs->imap, ino, new_inode);
1532         }
1533         io_channel_flush(rfs->old_fs->io);
1534
1535 errout:
1536         ext2fs_blocks_count_set(rfs->old_fs->super, orig_size);
1537         if (rfs->bmap) {
1538                 ext2fs_free_extent_table(rfs->bmap);
1539                 rfs->bmap = 0;
1540         }
1541         if (scan)
1542                 ext2fs_close_inode_scan(scan);
1543         if (block_buf)
1544                 ext2fs_free_mem(&block_buf);
1545         free(inode);
1546         return retval;
1547 }
1548
1549 /* --------------------------------------------------------------------
1550  *
1551  * Resize processing, phase 4.
1552  *
1553  * --------------------------------------------------------------------
1554  */
1555
1556 struct istruct {
1557         ext2_resize_t rfs;
1558         errcode_t       err;
1559         unsigned int    max_dirs;
1560         unsigned int    num;
1561 };
1562
1563 static int check_and_change_inodes(ext2_ino_t dir,
1564                                    int entry EXT2FS_ATTR((unused)),
1565                                    struct ext2_dir_entry *dirent, int offset,
1566                                    int  blocksize EXT2FS_ATTR((unused)),
1567                                    char *buf EXT2FS_ATTR((unused)),
1568                                    void *priv_data)
1569 {
1570         struct istruct *is = (struct istruct *) priv_data;
1571         struct ext2_inode       inode;
1572         ext2_ino_t              new_inode;
1573         errcode_t               retval;
1574
1575         if (is->rfs->progress && offset == 0) {
1576                 io_channel_flush(is->rfs->old_fs->io);
1577                 is->err = (is->rfs->progress)(is->rfs,
1578                                               E2_RSZ_INODE_REF_UPD_PASS,
1579                                               ++is->num, is->max_dirs);
1580                 if (is->err)
1581                         return DIRENT_ABORT;
1582         }
1583
1584         if (!dirent->inode)
1585                 return 0;
1586
1587         new_inode = ext2fs_extent_translate(is->rfs->imap, dirent->inode);
1588
1589         if (!new_inode)
1590                 return 0;
1591 #ifdef RESIZE2FS_DEBUG
1592         if (is->rfs->flags & RESIZE_DEBUG_INODEMAP)
1593                 printf("Inode translate (dir=%u, name=%.*s, %u->%u)\n",
1594                        dir, dirent->name_len&0xFF, dirent->name,
1595                        dirent->inode, new_inode);
1596 #endif
1597
1598         dirent->inode = new_inode;
1599
1600         /* Update the directory mtime and ctime */
1601         retval = ext2fs_read_inode(is->rfs->old_fs, dir, &inode);
1602         if (retval == 0) {
1603                 inode.i_mtime = inode.i_ctime = time(0);
1604                 is->err = ext2fs_write_inode(is->rfs->old_fs, dir, &inode);
1605                 if (is->err)
1606                         return DIRENT_ABORT;
1607         }
1608
1609         return DIRENT_CHANGED;
1610 }
1611
1612 static errcode_t inode_ref_fix(ext2_resize_t rfs)
1613 {
1614         errcode_t               retval;
1615         struct istruct          is;
1616
1617         if (!rfs->imap)
1618                 return 0;
1619
1620         /*
1621          * Now, we iterate over all of the directories to update the
1622          * inode references
1623          */
1624         is.num = 0;
1625         is.max_dirs = ext2fs_dblist_count2(rfs->old_fs->dblist);
1626         is.rfs = rfs;
1627         is.err = 0;
1628
1629         if (rfs->progress) {
1630                 retval = (rfs->progress)(rfs, E2_RSZ_INODE_REF_UPD_PASS,
1631                                          0, is.max_dirs);
1632                 if (retval)
1633                         goto errout;
1634         }
1635
1636         retval = ext2fs_dblist_dir_iterate(rfs->old_fs->dblist,
1637                                            DIRENT_FLAG_INCLUDE_EMPTY, 0,
1638                                            check_and_change_inodes, &is);
1639         if (retval)
1640                 goto errout;
1641         if (is.err) {
1642                 retval = is.err;
1643                 goto errout;
1644         }
1645
1646         if (rfs->progress && (is.num < is.max_dirs))
1647                 (rfs->progress)(rfs, E2_RSZ_INODE_REF_UPD_PASS,
1648                                 is.max_dirs, is.max_dirs);
1649
1650 errout:
1651         ext2fs_free_extent_table(rfs->imap);
1652         rfs->imap = 0;
1653         return retval;
1654 }
1655
1656
1657 /* --------------------------------------------------------------------
1658  *
1659  * Resize processing, phase 5.
1660  *
1661  * In this phase we actually move the inode table around, and then
1662  * update the summary statistics.  This is scary, since aborting here
1663  * will potentially scramble the filesystem.  (We are moving the
1664  * inode tables around in place, and so the potential for lost data,
1665  * or at the very least scrambling the mapping between filenames and
1666  * inode numbers is very high in case of a power failure here.)
1667  * --------------------------------------------------------------------
1668  */
1669
1670
1671 /*
1672  * A very scary routine --- this one moves the inode table around!!!
1673  *
1674  * After this you have to use the rfs->new_fs file handle to read and
1675  * write inodes.
1676  */
1677 static errcode_t move_itables(ext2_resize_t rfs)
1678 {
1679         int             n, num, size;
1680         long long       diff;
1681         dgrp_t          i, max_groups;
1682         ext2_filsys     fs = rfs->new_fs;
1683         char            *cp;
1684         blk64_t         old_blk, new_blk, blk;
1685         errcode_t       retval;
1686         int             j, to_move, moved;
1687
1688         max_groups = fs->group_desc_count;
1689         if (max_groups > rfs->old_fs->group_desc_count)
1690                 max_groups = rfs->old_fs->group_desc_count;
1691
1692         size = fs->blocksize * fs->inode_blocks_per_group;
1693         if (!rfs->itable_buf) {
1694                 retval = ext2fs_get_mem(size, &rfs->itable_buf);
1695                 if (retval)
1696                         return retval;
1697         }
1698
1699         /*
1700          * Figure out how many inode tables we need to move
1701          */
1702         to_move = moved = 0;
1703         for (i=0; i < max_groups; i++)
1704                 if (ext2fs_inode_table_loc(rfs->old_fs, i) !=
1705                     ext2fs_inode_table_loc(fs, i))
1706                         to_move++;
1707
1708         if (to_move == 0)
1709                 return 0;
1710
1711         if (rfs->progress) {
1712                 retval = rfs->progress(rfs, E2_RSZ_MOVE_ITABLE_PASS,
1713                                        0, to_move);
1714                 if (retval)
1715                         goto errout;
1716         }
1717
1718         rfs->old_fs->flags |= EXT2_FLAG_MASTER_SB_ONLY;
1719
1720         for (i=0; i < max_groups; i++) {
1721                 old_blk = ext2fs_inode_table_loc(rfs->old_fs, i);
1722                 new_blk = ext2fs_inode_table_loc(fs, i);
1723                 diff = new_blk - old_blk;
1724
1725 #ifdef RESIZE2FS_DEBUG
1726                 if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
1727                         printf("Itable move group %d block %llu->%llu (diff %lld)\n",
1728                                i, old_blk, new_blk, diff);
1729 #endif
1730
1731                 if (!diff)
1732                         continue;
1733
1734                 retval = io_channel_read_blk64(fs->io, old_blk,
1735                                                fs->inode_blocks_per_group,
1736                                                rfs->itable_buf);
1737                 if (retval)
1738                         goto errout;
1739                 /*
1740                  * The end of the inode table segment often contains
1741                  * all zeros, and we're often only moving the inode
1742                  * table down a block or two.  If so, we can optimize
1743                  * things by not rewriting blocks that we know to be zero
1744                  * already.
1745                  */
1746                 for (cp = rfs->itable_buf+size-1, n=0; n < size; n++, cp--)
1747                         if (*cp)
1748                                 break;
1749                 n = n >> EXT2_BLOCK_SIZE_BITS(fs->super);
1750 #ifdef RESIZE2FS_DEBUG
1751                 if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
1752                         printf("%d blocks of zeros...\n", n);
1753 #endif
1754                 num = fs->inode_blocks_per_group;
1755                 if (n > diff)
1756                         num -= n;
1757
1758                 retval = io_channel_write_blk64(fs->io, new_blk,
1759                                                 num, rfs->itable_buf);
1760                 if (retval) {
1761                         io_channel_write_blk64(fs->io, old_blk,
1762                                                num, rfs->itable_buf);
1763                         goto errout;
1764                 }
1765                 if (n > diff) {
1766                         retval = io_channel_write_blk64(fs->io,
1767                               old_blk + fs->inode_blocks_per_group,
1768                               diff, (rfs->itable_buf +
1769                                      (fs->inode_blocks_per_group - diff) *
1770                                      fs->blocksize));
1771                         if (retval)
1772                                 goto errout;
1773                 }
1774
1775                 for (blk = ext2fs_inode_table_loc(rfs->old_fs, i), j=0;
1776                      j < fs->inode_blocks_per_group ; j++, blk++)
1777                         ext2fs_block_alloc_stats2(fs, blk, -1);
1778
1779                 ext2fs_inode_table_loc_set(rfs->old_fs, i, new_blk);
1780                 ext2fs_group_desc_csum_set(rfs->old_fs, i);
1781                 ext2fs_mark_super_dirty(rfs->old_fs);
1782                 ext2fs_flush(rfs->old_fs);
1783
1784                 if (rfs->progress) {
1785                         retval = rfs->progress(rfs, E2_RSZ_MOVE_ITABLE_PASS,
1786                                                ++moved, to_move);
1787                         if (retval)
1788                                 goto errout;
1789                 }
1790         }
1791         mark_table_blocks(fs, fs->block_map);
1792         ext2fs_flush(fs);
1793 #ifdef RESIZE2FS_DEBUG
1794         if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE)
1795                 printf("Inode table move finished.\n");
1796 #endif
1797         return 0;
1798
1799 errout:
1800         return retval;
1801 }
1802
1803 /*
1804  * Fix the resize inode
1805  */
1806 static errcode_t fix_resize_inode(ext2_filsys fs)
1807 {
1808         struct ext2_inode       inode;
1809         errcode_t               retval;
1810         char                    *block_buf = NULL;
1811
1812         if (!(fs->super->s_feature_compat &
1813               EXT2_FEATURE_COMPAT_RESIZE_INODE))
1814                 return 0;
1815
1816         retval = ext2fs_get_mem(fs->blocksize, &block_buf);
1817         if (retval) goto errout;
1818
1819         retval = ext2fs_read_inode(fs, EXT2_RESIZE_INO, &inode);
1820         if (retval) goto errout;
1821
1822         ext2fs_iblk_set(fs, &inode, 1);
1823
1824         retval = ext2fs_write_inode(fs, EXT2_RESIZE_INO, &inode);
1825         if (retval) goto errout;
1826
1827         if (!inode.i_block[EXT2_DIND_BLOCK]) {
1828                 /*
1829                  * Avoid zeroing out block #0; that's rude.  This
1830                  * should never happen anyway since the filesystem
1831                  * should be fsck'ed and we assume it is consistent.
1832                  */
1833                 fprintf(stderr,
1834                         _("Should never happen: resize inode corrupt!\n"));
1835                 exit(1);
1836         }
1837
1838         memset(block_buf, 0, fs->blocksize);
1839
1840         retval = io_channel_write_blk64(fs->io, inode.i_block[EXT2_DIND_BLOCK],
1841                                         1, block_buf);
1842         if (retval) goto errout;
1843
1844         retval = ext2fs_create_resize_inode(fs);
1845         if (retval)
1846                 goto errout;
1847
1848 errout:
1849         if (block_buf)
1850                 ext2fs_free_mem(&block_buf);
1851         return retval;
1852 }
1853
1854 /*
1855  * Finally, recalculate the summary information
1856  */
1857 static errcode_t ext2fs_calculate_summary_stats(ext2_filsys fs)
1858 {
1859         blk64_t         blk;
1860         ext2_ino_t      ino;
1861         unsigned int    group = 0;
1862         unsigned int    count = 0;
1863         blk64_t         total_blocks_free = 0;
1864         int             total_inodes_free = 0;
1865         int             group_free = 0;
1866         int             uninit = 0;
1867         blk64_t         super_blk, old_desc_blk, new_desc_blk;
1868         int             old_desc_blocks;
1869
1870         /*
1871          * First calculate the block statistics
1872          */
1873         uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_BLOCK_UNINIT);
1874         ext2fs_super_and_bgd_loc2(fs, group, &super_blk, &old_desc_blk,
1875                                   &new_desc_blk, 0);
1876         if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
1877                 old_desc_blocks = fs->super->s_first_meta_bg;
1878         else
1879                 old_desc_blocks = fs->desc_blocks +
1880                         fs->super->s_reserved_gdt_blocks;
1881         for (blk = B2C(fs->super->s_first_data_block);
1882              blk < ext2fs_blocks_count(fs->super);
1883              blk += EXT2FS_CLUSTER_RATIO(fs)) {
1884                 if ((uninit &&
1885                      !(EQ_CLSTR(blk, super_blk) ||
1886                        ((old_desc_blk && old_desc_blocks &&
1887                          GE_CLSTR(blk, old_desc_blk) &&
1888                          LT_CLSTR(blk, old_desc_blk + old_desc_blocks))) ||
1889                        ((new_desc_blk && EQ_CLSTR(blk, new_desc_blk))) ||
1890                        EQ_CLSTR(blk, ext2fs_block_bitmap_loc(fs, group)) ||
1891                        EQ_CLSTR(blk, ext2fs_inode_bitmap_loc(fs, group)) ||
1892                        ((GE_CLSTR(blk, ext2fs_inode_table_loc(fs, group)) &&
1893                          LT_CLSTR(blk, ext2fs_inode_table_loc(fs, group)
1894                                   + fs->inode_blocks_per_group))))) ||
1895                     (!ext2fs_fast_test_block_bitmap2(fs->block_map, blk))) {
1896                         group_free++;
1897                         total_blocks_free++;
1898                 }
1899                 count++;
1900                 if ((count == fs->super->s_clusters_per_group) ||
1901                     EQ_CLSTR(blk, ext2fs_blocks_count(fs->super)-1)) {
1902                         ext2fs_bg_free_blocks_count_set(fs, group, group_free);
1903                         ext2fs_group_desc_csum_set(fs, group);
1904                         group++;
1905                         if (group >= fs->group_desc_count)
1906                                 break;
1907                         count = 0;
1908                         group_free = 0;
1909                         uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_BLOCK_UNINIT);
1910                         ext2fs_super_and_bgd_loc2(fs, group, &super_blk,
1911                                                   &old_desc_blk,
1912                                                   &new_desc_blk, 0);
1913                         if (fs->super->s_feature_incompat &
1914                             EXT2_FEATURE_INCOMPAT_META_BG)
1915                                 old_desc_blocks = fs->super->s_first_meta_bg;
1916                         else
1917                                 old_desc_blocks = fs->desc_blocks +
1918                                         fs->super->s_reserved_gdt_blocks;
1919                 }
1920         }
1921         total_blocks_free = C2B(total_blocks_free);
1922         ext2fs_free_blocks_count_set(fs->super, total_blocks_free);
1923
1924         /*
1925          * Next, calculate the inode statistics
1926          */
1927         group_free = 0;
1928         count = 0;
1929         group = 0;
1930
1931         /* Protect loop from wrap-around if s_inodes_count maxed */
1932         uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_INODE_UNINIT);
1933         for (ino = 1; ino <= fs->super->s_inodes_count && ino > 0; ino++) {
1934                 if (uninit ||
1935                     !ext2fs_fast_test_inode_bitmap2(fs->inode_map, ino)) {
1936                         group_free++;
1937                         total_inodes_free++;
1938                 }
1939                 count++;
1940                 if ((count == fs->super->s_inodes_per_group) ||
1941                     (ino == fs->super->s_inodes_count)) {
1942                         ext2fs_bg_free_inodes_count_set(fs, group, group_free);
1943                         ext2fs_group_desc_csum_set(fs, group);
1944                         group++;
1945                         if (group >= fs->group_desc_count)
1946                                 break;
1947                         count = 0;
1948                         group_free = 0;
1949                         uninit = ext2fs_bg_flags_test(fs, group, EXT2_BG_INODE_UNINIT);
1950                 }
1951         }
1952         fs->super->s_free_inodes_count = total_inodes_free;
1953         ext2fs_mark_super_dirty(fs);
1954         return 0;
1955 }
1956
1957 /*
1958  *  Journal may have been relocated; update the backup journal blocks
1959  *  in the superblock.
1960  */
1961 static errcode_t fix_sb_journal_backup(ext2_filsys fs)
1962 {
1963         errcode_t         retval;
1964         struct ext2_inode inode;
1965
1966         if (!(fs->super->s_feature_compat & EXT3_FEATURE_COMPAT_HAS_JOURNAL))
1967                 return 0;
1968
1969         /* External journal? Nothing to do. */
1970         if (fs->super->s_journal_dev && !fs->super->s_journal_inum)
1971                 return 0;
1972
1973         retval = ext2fs_read_inode(fs, fs->super->s_journal_inum, &inode);
1974         if (retval)
1975                 return retval;
1976         memcpy(fs->super->s_jnl_blocks, inode.i_block, EXT2_N_BLOCKS*4);
1977         fs->super->s_jnl_blocks[15] = inode.i_size_high;
1978         fs->super->s_jnl_blocks[16] = inode.i_size;
1979         fs->super->s_jnl_backup_type = EXT3_JNL_BACKUP_BLOCKS;
1980         ext2fs_mark_super_dirty(fs);
1981         return 0;
1982 }
1983
1984 static int calc_group_overhead(ext2_filsys fs, blk64_t grp,
1985                                int old_desc_blocks)
1986 {
1987         blk64_t super_blk, old_desc_blk, new_desc_blk;
1988         int overhead;
1989
1990         /* inode table blocks plus allocation bitmaps */
1991         overhead = fs->inode_blocks_per_group + 2;
1992
1993         ext2fs_super_and_bgd_loc2(fs, grp, &super_blk,
1994                                   &old_desc_blk, &new_desc_blk, 0);
1995         if ((grp == 0) || super_blk)
1996                 overhead++;
1997         if (old_desc_blk)
1998                 overhead += old_desc_blocks;
1999         else if (new_desc_blk)
2000                 overhead++;
2001         return overhead;
2002 }
2003
2004
2005 /*
2006  * calcluate the minimum number of blocks the given fs can be resized to
2007  */
2008 blk64_t calculate_minimum_resize_size(ext2_filsys fs)
2009 {
2010         ext2_ino_t inode_count;
2011         blk64_t blks_needed, groups, data_blocks;
2012         blk64_t grp, data_needed, last_start;
2013         blk64_t overhead = 0;
2014         int old_desc_blocks;
2015         int extra_groups = 0;
2016         int flexbg_size = 1 << fs->super->s_log_groups_per_flex;
2017
2018         /*
2019          * first figure out how many group descriptors we need to
2020          * handle the number of inodes we have
2021          */
2022         inode_count = fs->super->s_inodes_count -
2023                 fs->super->s_free_inodes_count;
2024         blks_needed = ext2fs_div_ceil(inode_count,
2025                                       fs->super->s_inodes_per_group) *
2026                 EXT2_BLOCKS_PER_GROUP(fs->super);
2027         groups = ext2fs_div64_ceil(blks_needed,
2028                                    EXT2_BLOCKS_PER_GROUP(fs->super));
2029
2030         /*
2031          * number of old-style block group descriptor blocks
2032          */
2033         if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG)
2034                 old_desc_blocks = fs->super->s_first_meta_bg;
2035         else
2036                 old_desc_blocks = fs->desc_blocks +
2037                         fs->super->s_reserved_gdt_blocks;
2038
2039         /* calculate how many blocks are needed for data */
2040         data_needed = ext2fs_blocks_count(fs->super) -
2041                 ext2fs_free_blocks_count(fs->super);
2042
2043         for (grp = 0; grp < fs->group_desc_count; grp++)
2044                 data_needed -= calc_group_overhead(fs, grp, old_desc_blocks);
2045
2046         /*
2047          * For ext4 we need to allow for up to a flex_bg worth of
2048          * inode tables of slack space so the resize operation can be
2049          * guaranteed to finish.
2050          */
2051         if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_FLEX_BG) {
2052                 extra_groups = flexbg_size - (groups & (flexbg_size - 1));
2053                 data_needed += fs->inode_blocks_per_group * extra_groups;
2054                 extra_groups = groups % flexbg_size;
2055         }
2056
2057         /*
2058          * figure out how many data blocks we have given the number of groups
2059          * we need for our inodes
2060          */
2061         data_blocks = groups * EXT2_BLOCKS_PER_GROUP(fs->super);
2062         last_start = 0;
2063         for (grp = 0; grp < groups; grp++) {
2064                 overhead = calc_group_overhead(fs, grp, old_desc_blocks);
2065
2066                 /*
2067                  * we want to keep track of how much data we can store in
2068                  * the groups leading up to the last group so we can determine
2069                  * how big the last group needs to be
2070                  */
2071                 if (grp != (groups - 1))
2072                         last_start += EXT2_BLOCKS_PER_GROUP(fs->super) -
2073                                 overhead;
2074
2075                 data_blocks -= overhead;
2076         }
2077
2078         /*
2079          * if we need more group descriptors in order to accomodate our data
2080          * then we need to add them here
2081          */
2082         while (data_needed > data_blocks) {
2083                 blk64_t remainder = data_needed - data_blocks;
2084                 blk64_t extra_grps;
2085
2086                 /* figure out how many more groups we need for the data */
2087                 extra_grps = ext2fs_div64_ceil(remainder,
2088                                                EXT2_BLOCKS_PER_GROUP(fs->super));
2089
2090                 data_blocks += extra_grps * EXT2_BLOCKS_PER_GROUP(fs->super);
2091
2092                 /* ok we have to account for the last group */
2093                 overhead = calc_group_overhead(fs, groups-1, old_desc_blocks);
2094                 last_start += EXT2_BLOCKS_PER_GROUP(fs->super) - overhead;
2095
2096                 for (grp = groups; grp < groups+extra_grps; grp++) {
2097                         overhead = calc_group_overhead(fs, grp,
2098                                                        old_desc_blocks);
2099
2100                         /*
2101                          * again, we need to see how much data we cram into
2102                          * all of the groups leading up to the last group
2103                          */
2104                         if (grp != (groups + extra_grps - 1))
2105                                 last_start += EXT2_BLOCKS_PER_GROUP(fs->super)
2106                                         - overhead;
2107
2108                         data_blocks -= overhead;
2109                 }
2110
2111                 groups += extra_grps;
2112                 extra_groups += extra_grps;
2113                 if (fs->super->s_feature_incompat
2114                         & EXT4_FEATURE_INCOMPAT_FLEX_BG
2115                     && extra_groups > flexbg_size) {
2116                         /*
2117                          * For ext4 we need to allow for up to a flex_bg worth
2118                          * of inode tables of slack space so the resize
2119                          * operation can be guaranteed to finish.
2120                          */
2121                         extra_groups = flexbg_size -
2122                                                 (groups & (flexbg_size - 1));
2123                         data_needed += (fs->inode_blocks_per_group *
2124                                         extra_groups);
2125                         extra_groups = groups % flexbg_size;
2126                 }
2127         }
2128
2129         /* now for the fun voodoo */
2130         overhead = calc_group_overhead(fs, groups-1, old_desc_blocks);
2131
2132         /*
2133          * if this is the case then the last group is going to have data in it
2134          * so we need to adjust the size of the last group accordingly
2135          */
2136         if (last_start < data_needed) {
2137                 blk64_t remainder = data_needed - last_start;
2138
2139                 /*
2140                  * 50 is a magic number that mkfs/resize uses to see if its
2141                  * even worth making/resizing the fs.  basically you need to
2142                  * have at least 50 blocks in addition to the blocks needed
2143                  * for the metadata in the last group
2144                  */
2145                 if (remainder > 50)
2146                         overhead += remainder;
2147                 else
2148                         overhead += 50;
2149         } else
2150                 overhead += 50;
2151
2152         overhead += fs->super->s_first_data_block;
2153
2154         /*
2155          * since our last group doesn't have to be BLOCKS_PER_GROUP large, we
2156          * only do groups-1, and then add the number of blocks needed to
2157          * handle the group descriptor metadata+data that we need
2158          */
2159         blks_needed = (groups-1) * EXT2_BLOCKS_PER_GROUP(fs->super);
2160         blks_needed += overhead;
2161
2162         /*
2163          * If at this point we've already added up more "needed" than
2164          * the current size, just return current size as minimum.
2165          */
2166         if (blks_needed >= ext2fs_blocks_count(fs->super))
2167                 return ext2fs_blocks_count(fs->super);
2168         /*
2169          * We need to reserve a few extra blocks if extents are
2170          * enabled, in case we need to grow the extent tree.  The more
2171          * we shrink the file system, the more space we need.
2172          */
2173         if (fs->super->s_feature_incompat & EXT3_FEATURE_INCOMPAT_EXTENTS)
2174                 blks_needed += (ext2fs_blocks_count(fs->super) -
2175                                 blks_needed)/500;
2176
2177         return blks_needed;
2178 }