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