1 /* 2 * resize2fs.c --- ext2 main routine 3 * 4 * Copyright (C) 1997, 1998 by Theodore Ts'o and 5 * PowerQuest, Inc. 6 * 7 * Copyright (C) 1999, 2000 by Theosore Ts'o 8 * 9 * %Begin-Header% 10 * This file may be redistributed under the terms of the GNU Public 11 * License. 12 * %End-Header% 13 */ 14 15 /* 16 * Resizing a filesystem consists of the following phases: 17 * 18 * 1. Adjust superblock and write out new parts of the inode 19 * table 20 * 2. Determine blocks which need to be relocated, and copy the 21 * contents of blocks from their old locations to the new ones. 22 * 3. Scan the inode table, doing the following: 23 * a. If blocks have been moved, update the block 24 * pointers in the inodes and indirect blocks to 25 * point at the new block locations. 26 * b. If parts of the inode table need to be evacuated, 27 * copy inodes from their old locations to their 28 * new ones. 29 * c. If (b) needs to be done, note which blocks contain 30 * directory information, since we will need to 31 * update the directory information. 32 * 4. Update the directory blocks with the new inode locations. 33 * 5. Move the inode tables, if necessary. 34 */ 35 36 #include "resize2fs.h" 37 #include <time.h> 38 39 #ifdef __linux__ /* Kludge for debugging */ 40 #define RESIZE2FS_DEBUG 41 #endif 42 43 static errcode_t adjust_superblock(ext2_resize_t rfs, blk_t new_size); 44 static errcode_t blocks_to_move(ext2_resize_t rfs); 45 static errcode_t block_mover(ext2_resize_t rfs); 46 static errcode_t inode_scan_and_fix(ext2_resize_t rfs); 47 static errcode_t inode_ref_fix(ext2_resize_t rfs); 48 static errcode_t move_itables(ext2_resize_t rfs); 49 static errcode_t fix_resize_inode(ext2_filsys fs); 50 static errcode_t ext2fs_calculate_summary_stats(ext2_filsys fs); 51 52 /* 53 * Some helper CPP macros 54 */ 55 #define FS_BLOCK_BM(fs, i) ((fs)->group_desc[(i)].bg_block_bitmap) 56 #define FS_INODE_BM(fs, i) ((fs)->group_desc[(i)].bg_inode_bitmap) 57 #define FS_INODE_TB(fs, i) ((fs)->group_desc[(i)].bg_inode_table) 58 59 #define IS_BLOCK_BM(fs, i, blk) ((blk) == FS_BLOCK_BM((fs),(i))) 60 #define IS_INODE_BM(fs, i, blk) ((blk) == FS_INODE_BM((fs),(i))) 61 62 #define IS_INODE_TB(fs, i, blk) (((blk) >= FS_INODE_TB((fs), (i))) && \ 63 ((blk) < (FS_INODE_TB((fs), (i)) + \ 64 (fs)->inode_blocks_per_group))) 65 66 67 68 /* 69 * This is the top-level routine which does the dirty deed.... 70 */ 71 errcode_t resize_fs(ext2_filsys fs, blk_t *new_size, int flags, 72 errcode_t (*progress)(ext2_resize_t rfs, int pass, 73 unsigned long cur, 74 unsigned long max_val)) 75 { 76 ext2_resize_t rfs; 77 errcode_t retval; 78 79 retval = ext2fs_read_bitmaps(fs); 80 if (retval) 81 return retval; 82 83 /* 84 * Create the data structure 85 */ 86 retval = ext2fs_get_mem(sizeof(struct ext2_resize_struct), &rfs); 87 if (retval) 88 return retval; 89 memset(rfs, 0, sizeof(struct ext2_resize_struct)); 90 91 rfs->old_fs = fs; 92 rfs->flags = flags; 93 rfs->itable_buf = 0; 94 rfs->progress = progress; 95 retval = ext2fs_dup_handle(fs, &rfs->new_fs); 96 if (retval) 97 goto errout; 98 99 retval = adjust_superblock(rfs, *new_size); 100 if (retval) 101 goto errout; 102 103 *new_size = rfs->new_fs->super->s_blocks_count; 104 105 retval = blocks_to_move(rfs); 106 if (retval) 107 goto errout; 108 109 #ifdef RESIZE2FS_DEBUG 110 if (rfs->flags & RESIZE_DEBUG_BMOVE) 111 printf("Number of free blocks: %u/%u, Needed: %d\n", 112 rfs->old_fs->super->s_free_blocks_count, 113 rfs->new_fs->super->s_free_blocks_count, 114 rfs->needed_blocks); 115 #endif 116 117 retval = block_mover(rfs); 118 if (retval) 119 goto errout; 120 121 retval = inode_scan_and_fix(rfs); 122 if (retval) 123 goto errout; 124 125 retval = inode_ref_fix(rfs); 126 if (retval) 127 goto errout; 128 129 retval = move_itables(rfs); 130 if (retval) 131 goto errout; 132 133 retval = ext2fs_calculate_summary_stats(rfs->new_fs); 134 if (retval) 135 goto errout; 136 137 retval = fix_resize_inode(rfs->new_fs); 138 if (retval) 139 goto errout; 140 141 rfs->new_fs->flags &= ~EXT2_FLAG_MASTER_SB_ONLY; 142 retval = ext2fs_close(rfs->new_fs); 143 if (retval) 144 goto errout; 145 146 rfs->flags = flags; 147 148 ext2fs_free(rfs->old_fs); 149 if (rfs->itable_buf) 150 ext2fs_free_mem(&rfs->itable_buf); 151 ext2fs_free_mem(&rfs); 152 153 return 0; 154 155 errout: 156 if (rfs->new_fs) 157 ext2fs_free(rfs->new_fs); 158 if (rfs->itable_buf) 159 ext2fs_free_mem(&rfs->itable_buf); 160 ext2fs_free_mem(&rfs); 161 return retval; 162 } 163 164 /* -------------------------------------------------------------------- 165 * 166 * Resize processing, phase 1. 167 * 168 * In this phase we adjust the in-memory superblock information, and 169 * initialize any new parts of the inode table. The new parts of the 170 * inode table are created in virgin disk space, so we can abort here 171 * without any side effects. 172 * -------------------------------------------------------------------- 173 */ 174 175 /* 176 * This routine is shared by the online and offline resize routines. 177 * All of the information which is adjusted in memory is done here. 178 */ 179 errcode_t adjust_fs_info(ext2_filsys fs, ext2_filsys old_fs, blk_t new_size) 180 { 181 errcode_t retval; 182 int overhead = 0; 183 int rem; 184 blk_t blk, group_block; 185 ext2_ino_t real_end; 186 int adj, old_numblocks, numblocks, adjblocks; 187 unsigned long i, j, old_desc_blocks, max_group; 188 unsigned int meta_bg, meta_bg_size; 189 int has_super; 190 unsigned long long new_inodes; /* u64 to check for overflow */ 191 192 fs->super->s_blocks_count = new_size; 193 194 retry: 195 fs->group_desc_count = ext2fs_div_ceil(fs->super->s_blocks_count - 196 fs->super->s_first_data_block, 197 EXT2_BLOCKS_PER_GROUP(fs->super)); 198 if (fs->group_desc_count == 0) 199 return EXT2_ET_TOOSMALL; 200 fs->desc_blocks = ext2fs_div_ceil(fs->group_desc_count, 201 EXT2_DESC_PER_BLOCK(fs->super)); 202 203 /* 204 * Overhead is the number of bookkeeping blocks per group. It 205 * includes the superblock backup, the group descriptor 206 * backups, the inode bitmap, the block bitmap, and the inode 207 * table. 208 */ 209 overhead = (int) (2 + fs->inode_blocks_per_group); 210 211 if (ext2fs_bg_has_super(fs, fs->group_desc_count - 1)) 212 overhead += 1 + fs->desc_blocks + 213 fs->super->s_reserved_gdt_blocks; 214 215 /* 216 * See if the last group is big enough to support the 217 * necessary data structures. If not, we need to get rid of 218 * it. 219 */ 220 rem = (fs->super->s_blocks_count - fs->super->s_first_data_block) % 221 fs->super->s_blocks_per_group; 222 if ((fs->group_desc_count == 1) && rem && (rem < overhead)) 223 return EXT2_ET_TOOSMALL; 224 if (rem && (rem < overhead+50)) { 225 fs->super->s_blocks_count -= rem; 226 goto retry; 227 } 228 /* 229 * Adjust the number of inodes 230 */ 231 new_inodes =(unsigned long long) fs->super->s_inodes_per_group * fs->group_desc_count; 232 if (new_inodes > ~0U) { 233 fprintf(stderr, _("inodes (%llu) must be less than %u"), 234 new_inodes, ~0U); 235 return EXT2_ET_TOO_MANY_INODES; 236 } 237 fs->super->s_inodes_count = fs->super->s_inodes_per_group * 238 fs->group_desc_count; 239 240 /* 241 * Adjust the number of free blocks 242 */ 243 blk = old_fs->super->s_blocks_count; 244 if (blk > fs->super->s_blocks_count) 245 fs->super->s_free_blocks_count -= 246 (blk - fs->super->s_blocks_count); 247 else 248 fs->super->s_free_blocks_count += 249 (fs->super->s_blocks_count - blk); 250 251 /* 252 * Adjust the number of reserved blocks 253 */ 254 blk = (__u64)old_fs->super->s_r_blocks_count * 100 / 255 old_fs->super->s_blocks_count; 256 fs->super->s_r_blocks_count = e2p_percent(blk, 257 fs->super->s_blocks_count); 258 259 /* 260 * Adjust the bitmaps for size 261 */ 262 retval = ext2fs_resize_inode_bitmap(fs->super->s_inodes_count, 263 fs->super->s_inodes_count, 264 fs->inode_map); 265 if (retval) goto errout; 266 267 real_end = ((EXT2_BLOCKS_PER_GROUP(fs->super) 268 * fs->group_desc_count)) - 1 + 269 fs->super->s_first_data_block; 270 retval = ext2fs_resize_block_bitmap(fs->super->s_blocks_count-1, 271 real_end, fs->block_map); 272 273 if (retval) goto errout; 274 275 /* 276 * Reallocate the group descriptors as necessary. 277 */ 278 if (old_fs->desc_blocks != fs->desc_blocks) { 279 retval = ext2fs_resize_mem(old_fs->desc_blocks * 280 fs->blocksize, 281 fs->desc_blocks * fs->blocksize, 282 &fs->group_desc); 283 if (retval) 284 goto errout; 285 if (fs->desc_blocks > old_fs->desc_blocks) 286 memset((char *) fs->group_desc + 287 (old_fs->desc_blocks * fs->blocksize), 0, 288 (fs->desc_blocks - old_fs->desc_blocks) * 289 fs->blocksize); 290 } 291 292 /* 293 * If the resize_inode feature is set, and we are changing the 294 * number of descriptor blocks, then adjust 295 * s_reserved_gdt_blocks if possible to avoid needing to move 296 * the inode table either now or in the future. 297 */ 298 if ((fs->super->s_feature_compat & 299 EXT2_FEATURE_COMPAT_RESIZE_INODE) && 300 (old_fs->desc_blocks != fs->desc_blocks)) { 301 int new; 302 303 new = ((int) fs->super->s_reserved_gdt_blocks) + 304 (old_fs->desc_blocks - fs->desc_blocks); 305 if (new < 0) 306 new = 0; 307 if (new > (int) fs->blocksize/4) 308 new = fs->blocksize/4; 309 fs->super->s_reserved_gdt_blocks = new; 310 if (new == 0) 311 fs->super->s_feature_compat &= 312 ~EXT2_FEATURE_COMPAT_RESIZE_INODE; 313 } 314 315 /* 316 * If we are shrinking the number block groups, we're done and 317 * can exit now. 318 */ 319 if (old_fs->group_desc_count > fs->group_desc_count) { 320 retval = 0; 321 goto errout; 322 } 323 324 /* 325 * Fix the count of the last (old) block group 326 */ 327 old_numblocks = (old_fs->super->s_blocks_count - 328 old_fs->super->s_first_data_block) % 329 old_fs->super->s_blocks_per_group; 330 if (!old_numblocks) 331 old_numblocks = old_fs->super->s_blocks_per_group; 332 if (old_fs->group_desc_count == fs->group_desc_count) { 333 numblocks = (fs->super->s_blocks_count - 334 fs->super->s_first_data_block) % 335 fs->super->s_blocks_per_group; 336 if (!numblocks) 337 numblocks = fs->super->s_blocks_per_group; 338 } else 339 numblocks = fs->super->s_blocks_per_group; 340 i = old_fs->group_desc_count - 1; 341 fs->group_desc[i].bg_free_blocks_count += (numblocks-old_numblocks); 342 343 /* 344 * If the number of block groups is staying the same, we're 345 * done and can exit now. (If the number block groups is 346 * shrinking, we had exited earlier.) 347 */ 348 if (old_fs->group_desc_count >= fs->group_desc_count) { 349 retval = 0; 350 goto errout; 351 } 352 353 /* 354 * Initialize the new block group descriptors 355 */ 356 group_block = fs->super->s_first_data_block + 357 old_fs->group_desc_count * fs->super->s_blocks_per_group; 358 359 adj = old_fs->group_desc_count; 360 max_group = fs->group_desc_count - adj; 361 if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG) 362 old_desc_blocks = fs->super->s_first_meta_bg; 363 else 364 old_desc_blocks = fs->desc_blocks + 365 fs->super->s_reserved_gdt_blocks; 366 for (i = old_fs->group_desc_count; 367 i < fs->group_desc_count; i++) { 368 memset(&fs->group_desc[i], 0, 369 sizeof(struct ext2_group_desc)); 370 adjblocks = 0; 371 372 if (i == fs->group_desc_count-1) { 373 numblocks = (fs->super->s_blocks_count - 374 fs->super->s_first_data_block) % 375 fs->super->s_blocks_per_group; 376 if (!numblocks) 377 numblocks = fs->super->s_blocks_per_group; 378 } else 379 numblocks = fs->super->s_blocks_per_group; 380 381 has_super = ext2fs_bg_has_super(fs, i); 382 if (has_super) { 383 ext2fs_mark_block_bitmap(fs->block_map, group_block); 384 adjblocks++; 385 } 386 meta_bg_size = (fs->blocksize / 387 sizeof (struct ext2_group_desc)); 388 meta_bg = i / meta_bg_size; 389 if (!(fs->super->s_feature_incompat & 390 EXT2_FEATURE_INCOMPAT_META_BG) || 391 (meta_bg < fs->super->s_first_meta_bg)) { 392 if (has_super) { 393 for (j=0; j < old_desc_blocks; j++) 394 ext2fs_mark_block_bitmap(fs->block_map, 395 group_block + 1 + j); 396 adjblocks += old_desc_blocks; 397 } 398 } else { 399 if (has_super) 400 has_super = 1; 401 if (((i % meta_bg_size) == 0) || 402 ((i % meta_bg_size) == 1) || 403 ((i % meta_bg_size) == (meta_bg_size-1))) 404 ext2fs_mark_block_bitmap(fs->block_map, 405 group_block + has_super); 406 } 407 408 adjblocks += 2 + fs->inode_blocks_per_group; 409 410 numblocks -= adjblocks; 411 fs->super->s_free_blocks_count -= adjblocks; 412 fs->super->s_free_inodes_count += 413 fs->super->s_inodes_per_group; 414 fs->group_desc[i].bg_free_blocks_count = numblocks; 415 fs->group_desc[i].bg_free_inodes_count = 416 fs->super->s_inodes_per_group; 417 fs->group_desc[i].bg_used_dirs_count = 0; 418 419 retval = ext2fs_allocate_group_table(fs, i, 0); 420 if (retval) goto errout; 421 422 group_block += fs->super->s_blocks_per_group; 423 } 424 retval = 0; 425 426 errout: 427 return (retval); 428 } 429 430 /* 431 * This routine adjusts the superblock and other data structures, both 432 * in disk as well as in memory... 433 */ 434 static errcode_t adjust_superblock(ext2_resize_t rfs, blk_t new_size) 435 { 436 ext2_filsys fs; 437 int adj = 0; 438 errcode_t retval; 439 blk_t group_block; 440 unsigned long i; 441 unsigned long max_group; 442 443 fs = rfs->new_fs; 444 ext2fs_mark_super_dirty(fs); 445 ext2fs_mark_bb_dirty(fs); 446 ext2fs_mark_ib_dirty(fs); 447 448 retval = adjust_fs_info(fs, rfs->old_fs, new_size); 449 if (retval) 450 goto errout; 451 452 /* 453 * Check to make sure there are enough inodes 454 */ 455 if ((rfs->old_fs->super->s_inodes_count - 456 rfs->old_fs->super->s_free_inodes_count) > 457 rfs->new_fs->super->s_inodes_count) { 458 retval = ENOSPC; 459 goto errout; 460 } 461 462 /* 463 * If we are shrinking the number block groups, we're done and 464 * can exit now. 465 */ 466 if (rfs->old_fs->group_desc_count > fs->group_desc_count) { 467 retval = 0; 468 goto errout; 469 } 470 471 /* 472 * If the number of block groups is staying the same, we're 473 * done and can exit now. (If the number block groups is 474 * shrinking, we had exited earlier.) 475 */ 476 if (rfs->old_fs->group_desc_count >= fs->group_desc_count) { 477 retval = 0; 478 goto errout; 479 } 480 481 /* 482 * Initialize the new block group descriptors 483 */ 484 retval = ext2fs_get_array(fs->blocksize, fs->inode_blocks_per_group, 485 &rfs->itable_buf); 486 if (retval) 487 goto errout; 488 489 memset(rfs->itable_buf, 0, fs->blocksize * fs->inode_blocks_per_group); 490 group_block = fs->super->s_first_data_block + 491 rfs->old_fs->group_desc_count * fs->super->s_blocks_per_group; 492 493 adj = rfs->old_fs->group_desc_count; 494 max_group = fs->group_desc_count - adj; 495 if (rfs->progress) { 496 retval = rfs->progress(rfs, E2_RSZ_EXTEND_ITABLE_PASS, 497 0, max_group); 498 if (retval) 499 goto errout; 500 } 501 for (i = rfs->old_fs->group_desc_count; 502 i < fs->group_desc_count; i++) { 503 /* 504 * Write out the new inode table 505 */ 506 retval = io_channel_write_blk(fs->io, 507 fs->group_desc[i].bg_inode_table, 508 fs->inode_blocks_per_group, 509 rfs->itable_buf); 510 if (retval) goto errout; 511 512 io_channel_flush(fs->io); 513 if (rfs->progress) { 514 retval = rfs->progress(rfs, E2_RSZ_EXTEND_ITABLE_PASS, 515 i - adj + 1, max_group); 516 if (retval) 517 goto errout; 518 } 519 group_block += fs->super->s_blocks_per_group; 520 } 521 io_channel_flush(fs->io); 522 retval = 0; 523 524 errout: 525 return retval; 526 } 527 528 /* -------------------------------------------------------------------- 529 * 530 * Resize processing, phase 2. 531 * 532 * In this phase we adjust determine which blocks need to be moved, in 533 * blocks_to_move(). We then copy the blocks to their ultimate new 534 * destinations using block_mover(). Since we are copying blocks to 535 * their new locations, again during this pass we can abort without 536 * any problems. 537 * -------------------------------------------------------------------- 538 */ 539 540 /* 541 * This helper function creates a block bitmap with all of the 542 * filesystem meta-data blocks. 543 */ 544 static errcode_t mark_table_blocks(ext2_filsys fs, 545 ext2fs_block_bitmap bmap) 546 { 547 blk_t b; 548 unsigned int j; 549 dgrp_t i; 550 unsigned long meta_bg_size; 551 unsigned int old_desc_blocks; 552 553 meta_bg_size = (fs->blocksize / sizeof (struct ext2_group_desc)); 554 if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG) 555 old_desc_blocks = fs->super->s_first_meta_bg; 556 else 557 old_desc_blocks = fs->desc_blocks + 558 fs->super->s_reserved_gdt_blocks; 559 for (i = 0; i < fs->group_desc_count; i++) { 560 ext2fs_reserve_super_and_bgd(fs, i, bmap); 561 562 /* 563 * Mark the blocks used for the inode table 564 */ 565 for (j = 0, b = fs->group_desc[i].bg_inode_table; 566 j < (unsigned int) fs->inode_blocks_per_group; 567 j++, b++) 568 ext2fs_mark_block_bitmap(bmap, b); 569 570 /* 571 * Mark block used for the block bitmap 572 */ 573 ext2fs_mark_block_bitmap(bmap, 574 fs->group_desc[i].bg_block_bitmap); 575 576 /* 577 * Mark block used for the inode bitmap 578 */ 579 ext2fs_mark_block_bitmap(bmap, 580 fs->group_desc[i].bg_inode_bitmap); 581 } 582 return 0; 583 } 584 585 /* 586 * This function checks to see if a particular block (either a 587 * superblock or a block group descriptor) overlaps with an inode or 588 * block bitmap block, or with the inode table. 589 */ 590 static void mark_fs_metablock(ext2_resize_t rfs, 591 ext2fs_block_bitmap meta_bmap, 592 int group, blk_t blk) 593 { 594 ext2_filsys fs = rfs->new_fs; 595 596 ext2fs_mark_block_bitmap(rfs->reserve_blocks, blk); 597 ext2fs_mark_block_bitmap(fs->block_map, blk); 598 599 /* 600 * Check to see if we overlap with the inode or block bitmap, 601 * or the inode tables. If not, and the block is in use, then 602 * mark it as a block to be moved. 603 */ 604 if (IS_BLOCK_BM(fs, group, blk)) { 605 FS_BLOCK_BM(fs, group) = 0; 606 rfs->needed_blocks++; 607 } else if (IS_INODE_BM(fs, group, blk)) { 608 FS_INODE_BM(fs, group) = 0; 609 rfs->needed_blocks++; 610 } else if (IS_INODE_TB(fs, group, blk)) { 611 FS_INODE_TB(fs, group) = 0; 612 rfs->needed_blocks++; 613 } else if (ext2fs_test_block_bitmap(rfs->old_fs->block_map, blk) && 614 !ext2fs_test_block_bitmap(meta_bmap, blk)) { 615 ext2fs_mark_block_bitmap(rfs->move_blocks, blk); 616 rfs->needed_blocks++; 617 } 618 } 619 620 621 /* 622 * This routine marks and unmarks reserved blocks in the new block 623 * bitmap. It also determines which blocks need to be moved and 624 * places this information into the move_blocks bitmap. 625 */ 626 static errcode_t blocks_to_move(ext2_resize_t rfs) 627 { 628 int j, has_super; 629 dgrp_t i, max_groups; 630 blk_t blk, group_blk; 631 unsigned long old_blocks, new_blocks; 632 unsigned int meta_bg, meta_bg_size; 633 errcode_t retval; 634 ext2_filsys fs, old_fs; 635 ext2fs_block_bitmap meta_bmap; 636 637 fs = rfs->new_fs; 638 old_fs = rfs->old_fs; 639 if (old_fs->super->s_blocks_count > fs->super->s_blocks_count) 640 fs = rfs->old_fs; 641 642 retval = ext2fs_allocate_block_bitmap(fs, _("reserved blocks"), 643 &rfs->reserve_blocks); 644 if (retval) 645 return retval; 646 647 retval = ext2fs_allocate_block_bitmap(fs, _("blocks to be moved"), 648 &rfs->move_blocks); 649 if (retval) 650 return retval; 651 652 retval = ext2fs_allocate_block_bitmap(fs, _("meta-data blocks"), 653 &meta_bmap); 654 if (retval) 655 return retval; 656 657 retval = mark_table_blocks(old_fs, meta_bmap); 658 if (retval) 659 return retval; 660 661 fs = rfs->new_fs; 662 663 /* 664 * If we're shrinking the filesystem, we need to move all of 665 * the blocks that don't fit any more 666 */ 667 for (blk = fs->super->s_blocks_count; 668 blk < old_fs->super->s_blocks_count; blk++) { 669 if (ext2fs_test_block_bitmap(old_fs->block_map, blk) && 670 !ext2fs_test_block_bitmap(meta_bmap, blk)) { 671 ext2fs_mark_block_bitmap(rfs->move_blocks, blk); 672 rfs->needed_blocks++; 673 } 674 ext2fs_mark_block_bitmap(rfs->reserve_blocks, blk); 675 } 676 677 if (fs->super->s_feature_incompat & EXT2_FEATURE_INCOMPAT_META_BG) { 678 old_blocks = old_fs->super->s_first_meta_bg; 679 new_blocks = fs->super->s_first_meta_bg; 680 } else { 681 old_blocks = old_fs->desc_blocks + old_fs->super->s_reserved_gdt_blocks; 682 new_blocks = fs->desc_blocks + fs->super->s_reserved_gdt_blocks; 683 } 684 685 if (old_blocks == new_blocks) { 686 retval = 0; 687 goto errout; 688 } 689 690 max_groups = fs->group_desc_count; 691 if (max_groups > old_fs->group_desc_count) 692 max_groups = old_fs->group_desc_count; 693 group_blk = old_fs->super->s_first_data_block; 694 /* 695 * If we're reducing the number of descriptor blocks, this 696 * makes life easy. :-) We just have to mark some extra 697 * blocks as free. 698 */ 699 if (old_blocks > new_blocks) { 700 for (i = 0; i < max_groups; i++) { 701 if (!ext2fs_bg_has_super(fs, i)) { 702 group_blk += fs->super->s_blocks_per_group; 703 continue; 704 } 705 for (blk = group_blk+1+new_blocks; 706 blk < group_blk+1+old_blocks; blk++) { 707 ext2fs_unmark_block_bitmap(fs->block_map, 708 blk); 709 rfs->needed_blocks--; 710 } 711 group_blk += fs->super->s_blocks_per_group; 712 } 713 retval = 0; 714 goto errout; 715 } 716 /* 717 * If we're increasing the number of descriptor blocks, life 718 * gets interesting.... 719 */ 720 meta_bg_size = (fs->blocksize / sizeof (struct ext2_group_desc)); 721 for (i = 0; i < max_groups; i++) { 722 has_super = ext2fs_bg_has_super(fs, i); 723 if (has_super) 724 mark_fs_metablock(rfs, meta_bmap, i, group_blk); 725 726 meta_bg = i / meta_bg_size; 727 if (!(fs->super->s_feature_incompat & 728 EXT2_FEATURE_INCOMPAT_META_BG) || 729 (meta_bg < fs->super->s_first_meta_bg)) { 730 if (has_super) { 731 for (blk = group_blk+1; 732 blk < group_blk + 1 + new_blocks; blk++) 733 mark_fs_metablock(rfs, meta_bmap, 734 i, blk); 735 } 736 } else { 737 if (has_super) 738 has_super = 1; 739 if (((i % meta_bg_size) == 0) || 740 ((i % meta_bg_size) == 1) || 741 ((i % meta_bg_size) == (meta_bg_size-1))) 742 mark_fs_metablock(rfs, meta_bmap, i, 743 group_blk + has_super); 744 } 745 746 if (fs->group_desc[i].bg_inode_table && 747 fs->group_desc[i].bg_inode_bitmap && 748 fs->group_desc[i].bg_block_bitmap) 749 goto next_group; 750 751 /* 752 * Reserve the existing meta blocks that we know 753 * aren't to be moved. 754 */ 755 if (fs->group_desc[i].bg_block_bitmap) 756 ext2fs_mark_block_bitmap(rfs->reserve_blocks, 757 fs->group_desc[i].bg_block_bitmap); 758 if (fs->group_desc[i].bg_inode_bitmap) 759 ext2fs_mark_block_bitmap(rfs->reserve_blocks, 760 fs->group_desc[i].bg_inode_bitmap); 761 if (fs->group_desc[i].bg_inode_table) 762 for (blk = fs->group_desc[i].bg_inode_table, j=0; 763 j < fs->inode_blocks_per_group ; j++, blk++) 764 ext2fs_mark_block_bitmap(rfs->reserve_blocks, 765 blk); 766 767 /* 768 * Allocate the missing data structures 769 */ 770 retval = ext2fs_allocate_group_table(fs, i, 771 rfs->reserve_blocks); 772 if (retval) 773 goto errout; 774 775 /* 776 * For those structures that have changed, we need to 777 * do bookkeepping. 778 */ 779 if (FS_BLOCK_BM(old_fs, i) != 780 (blk = FS_BLOCK_BM(fs, i))) { 781 ext2fs_mark_block_bitmap(fs->block_map, blk); 782 if (ext2fs_test_block_bitmap(old_fs->block_map, blk) && 783 !ext2fs_test_block_bitmap(meta_bmap, blk)) 784 ext2fs_mark_block_bitmap(rfs->move_blocks, 785 blk); 786 } 787 if (FS_INODE_BM(old_fs, i) != 788 (blk = FS_INODE_BM(fs, i))) { 789 ext2fs_mark_block_bitmap(fs->block_map, blk); 790 if (ext2fs_test_block_bitmap(old_fs->block_map, blk) && 791 !ext2fs_test_block_bitmap(meta_bmap, blk)) 792 ext2fs_mark_block_bitmap(rfs->move_blocks, 793 blk); 794 } 795 796 /* 797 * The inode table, if we need to relocate it, is 798 * handled specially. We have to reserve the blocks 799 * for both the old and the new inode table, since we 800 * can't have the inode table be destroyed during the 801 * block relocation phase. 802 */ 803 if (FS_INODE_TB(fs, i) == FS_INODE_TB(old_fs, i)) 804 goto next_group; /* inode table not moved */ 805 806 rfs->needed_blocks += fs->inode_blocks_per_group; 807 808 /* 809 * Mark the new inode table as in use in the new block 810 * allocation bitmap, and move any blocks that might 811 * be necessary. 812 */ 813 for (blk = fs->group_desc[i].bg_inode_table, j=0; 814 j < fs->inode_blocks_per_group ; j++, blk++) { 815 ext2fs_mark_block_bitmap(fs->block_map, blk); 816 if (ext2fs_test_block_bitmap(old_fs->block_map, blk) && 817 !ext2fs_test_block_bitmap(meta_bmap, blk)) 818 ext2fs_mark_block_bitmap(rfs->move_blocks, 819 blk); 820 } 821 822 /* 823 * Make sure the old inode table is reserved in the 824 * block reservation bitmap. 825 */ 826 for (blk = rfs->old_fs->group_desc[i].bg_inode_table, j=0; 827 j < fs->inode_blocks_per_group ; j++, blk++) 828 ext2fs_mark_block_bitmap(rfs->reserve_blocks, blk); 829 830 next_group: 831 group_blk += rfs->new_fs->super->s_blocks_per_group; 832 } 833 retval = 0; 834 835 errout: 836 if (meta_bmap) 837 ext2fs_free_block_bitmap(meta_bmap); 838 839 return retval; 840 } 841 842 /* 843 * This helper function tries to allocate a new block. We try to 844 * avoid hitting the original group descriptor blocks at least at 845 * first, since we want to make it possible to recover from a badly 846 * aborted resize operation as much as possible. 847 * 848 * In the future, I may further modify this routine to balance out 849 * where we get the new blocks across the various block groups. 850 * Ideally we would allocate blocks that corresponded with the block 851 * group of the containing inode, and keep contiguous blocks 852 * together. However, this very difficult to do efficiently, since we 853 * don't have the necessary information up front. 854 */ 855 856 #define AVOID_OLD 1 857 #define DESPERATION 2 858 859 static void init_block_alloc(ext2_resize_t rfs) 860 { 861 rfs->alloc_state = AVOID_OLD; 862 rfs->new_blk = rfs->new_fs->super->s_first_data_block; 863 #if 0 864 /* HACK for testing */ 865 if (rfs->new_fs->super->s_blocks_count > 866 rfs->old_fs->super->s_blocks_count) 867 rfs->new_blk = rfs->old_fs->super->s_blocks_count; 868 #endif 869 } 870 871 static blk_t get_new_block(ext2_resize_t rfs) 872 { 873 ext2_filsys fs = rfs->new_fs; 874 875 while (1) { 876 if (rfs->new_blk >= fs->super->s_blocks_count) { 877 if (rfs->alloc_state == DESPERATION) 878 return 0; 879 880 #ifdef RESIZE2FS_DEBUG 881 if (rfs->flags & RESIZE_DEBUG_BMOVE) 882 printf("Going into desperation mode " 883 "for block allocations\n"); 884 #endif 885 rfs->alloc_state = DESPERATION; 886 rfs->new_blk = fs->super->s_first_data_block; 887 continue; 888 } 889 if (ext2fs_test_block_bitmap(fs->block_map, rfs->new_blk) || 890 ext2fs_test_block_bitmap(rfs->reserve_blocks, 891 rfs->new_blk) || 892 ((rfs->alloc_state == AVOID_OLD) && 893 (rfs->new_blk < rfs->old_fs->super->s_blocks_count) && 894 ext2fs_test_block_bitmap(rfs->old_fs->block_map, 895 rfs->new_blk))) { 896 rfs->new_blk++; 897 continue; 898 } 899 return rfs->new_blk; 900 } 901 } 902 903 static errcode_t block_mover(ext2_resize_t rfs) 904 { 905 blk_t blk, old_blk, new_blk; 906 ext2_filsys fs = rfs->new_fs; 907 ext2_filsys old_fs = rfs->old_fs; 908 errcode_t retval; 909 int size, c; 910 int to_move, moved; 911 ext2_badblocks_list badblock_list = 0; 912 int bb_modified = 0; 913 914 retval = ext2fs_read_bb_inode(old_fs, &badblock_list); 915 if (retval) 916 return retval; 917 918 new_blk = fs->super->s_first_data_block; 919 if (!rfs->itable_buf) { 920 retval = ext2fs_get_array(fs->blocksize, 921 fs->inode_blocks_per_group, 922 &rfs->itable_buf); 923 if (retval) 924 return retval; 925 } 926 retval = ext2fs_create_extent_table(&rfs->bmap, 0); 927 if (retval) 928 return retval; 929 930 /* 931 * The first step is to figure out where all of the blocks 932 * will go. 933 */ 934 to_move = moved = 0; 935 init_block_alloc(rfs); 936 for (blk = old_fs->super->s_first_data_block; 937 blk < old_fs->super->s_blocks_count; blk++) { 938 if (!ext2fs_test_block_bitmap(old_fs->block_map, blk)) 939 continue; 940 if (!ext2fs_test_block_bitmap(rfs->move_blocks, blk)) 941 continue; 942 if (ext2fs_badblocks_list_test(badblock_list, blk)) { 943 ext2fs_badblocks_list_del(badblock_list, blk); 944 bb_modified++; 945 continue; 946 } 947 948 new_blk = get_new_block(rfs); 949 if (!new_blk) { 950 retval = ENOSPC; 951 goto errout; 952 } 953 ext2fs_mark_block_bitmap(fs->block_map, new_blk); 954 ext2fs_add_extent_entry(rfs->bmap, blk, new_blk); 955 to_move++; 956 } 957 958 if (to_move == 0) { 959 if (rfs->bmap) { 960 ext2fs_free_extent_table(rfs->bmap); 961 rfs->bmap = 0; 962 } 963 retval = 0; 964 goto errout; 965 } 966 967 /* 968 * Step two is to actually move the blocks 969 */ 970 retval = ext2fs_iterate_extent(rfs->bmap, 0, 0, 0); 971 if (retval) goto errout; 972 973 if (rfs->progress) { 974 retval = (rfs->progress)(rfs, E2_RSZ_BLOCK_RELOC_PASS, 975 0, to_move); 976 if (retval) 977 goto errout; 978 } 979 while (1) { 980 retval = ext2fs_iterate_extent(rfs->bmap, &old_blk, &new_blk, &size); 981 if (retval) goto errout; 982 if (!size) 983 break; 984 #ifdef RESIZE2FS_DEBUG 985 if (rfs->flags & RESIZE_DEBUG_BMOVE) 986 printf("Moving %d blocks %u->%u\n", 987 size, old_blk, new_blk); 988 #endif 989 do { 990 c = size; 991 if (c > fs->inode_blocks_per_group) 992 c = fs->inode_blocks_per_group; 993 retval = io_channel_read_blk(fs->io, old_blk, c, 994 rfs->itable_buf); 995 if (retval) goto errout; 996 retval = io_channel_write_blk(fs->io, new_blk, c, 997 rfs->itable_buf); 998 if (retval) goto errout; 999 size -= c; 1000 new_blk += c; 1001 old_blk += c; 1002 moved += c; 1003 if (rfs->progress) { 1004 io_channel_flush(fs->io); 1005 retval = (rfs->progress)(rfs, 1006 E2_RSZ_BLOCK_RELOC_PASS, 1007 moved, to_move); 1008 if (retval) 1009 goto errout; 1010 } 1011 } while (size > 0); 1012 io_channel_flush(fs->io); 1013 } 1014 1015 errout: 1016 if (badblock_list) { 1017 if (!retval && bb_modified) 1018 retval = ext2fs_update_bb_inode(old_fs, 1019 badblock_list); 1020 ext2fs_badblocks_list_free(badblock_list); 1021 } 1022 return retval; 1023 } 1024 1025 1026 /* -------------------------------------------------------------------- 1027 * 1028 * Resize processing, phase 3 1029 * 1030 * -------------------------------------------------------------------- 1031 */ 1032 1033 1034 struct process_block_struct { 1035 ext2_resize_t rfs; 1036 ext2_ino_t ino; 1037 struct ext2_inode * inode; 1038 errcode_t error; 1039 int is_dir; 1040 int changed; 1041 }; 1042 1043 static int process_block(ext2_filsys fs, blk_t *block_nr, 1044 e2_blkcnt_t blockcnt, 1045 blk_t ref_block EXT2FS_ATTR((unused)), 1046 int ref_offset EXT2FS_ATTR((unused)), void *priv_data) 1047 { 1048 struct process_block_struct *pb; 1049 errcode_t retval; 1050 blk_t block, new_block; 1051 int ret = 0; 1052 1053 pb = (struct process_block_struct *) priv_data; 1054 block = *block_nr; 1055 if (pb->rfs->bmap) { 1056 new_block = ext2fs_extent_translate(pb->rfs->bmap, block); 1057 if (new_block) { 1058 *block_nr = new_block; 1059 ret |= BLOCK_CHANGED; 1060 pb->changed = 1; 1061 #ifdef RESIZE2FS_DEBUG 1062 if (pb->rfs->flags & RESIZE_DEBUG_BMOVE) 1063 printf("ino=%u, blockcnt=%lld, %u->%u\n", 1064 pb->ino, blockcnt, block, new_block); 1065 #endif 1066 block = new_block; 1067 } 1068 } 1069 if (pb->is_dir) { 1070 retval = ext2fs_add_dir_block(fs->dblist, pb->ino, 1071 block, (int) blockcnt); 1072 if (retval) { 1073 pb->error = retval; 1074 ret |= BLOCK_ABORT; 1075 } 1076 } 1077 return ret; 1078 } 1079 1080 /* 1081 * Progress callback 1082 */ 1083 static errcode_t progress_callback(ext2_filsys fs, 1084 ext2_inode_scan scan EXT2FS_ATTR((unused)), 1085 dgrp_t group, void * priv_data) 1086 { 1087 ext2_resize_t rfs = (ext2_resize_t) priv_data; 1088 errcode_t retval; 1089 1090 /* 1091 * This check is to protect against old ext2 libraries. It 1092 * shouldn't be needed against new libraries. 1093 */ 1094 if ((group+1) == 0) 1095 return 0; 1096 1097 if (rfs->progress) { 1098 io_channel_flush(fs->io); 1099 retval = (rfs->progress)(rfs, E2_RSZ_INODE_SCAN_PASS, 1100 group+1, fs->group_desc_count); 1101 if (retval) 1102 return retval; 1103 } 1104 1105 return 0; 1106 } 1107 1108 static errcode_t inode_scan_and_fix(ext2_resize_t rfs) 1109 { 1110 struct process_block_struct pb; 1111 ext2_ino_t ino, new_inode; 1112 struct ext2_inode *inode = NULL; 1113 ext2_inode_scan scan = NULL; 1114 errcode_t retval; 1115 int group; 1116 char *block_buf = 0; 1117 ext2_ino_t start_to_move; 1118 blk_t orig_size, new_block; 1119 int inode_size; 1120 1121 if ((rfs->old_fs->group_desc_count <= 1122 rfs->new_fs->group_desc_count) && 1123 !rfs->bmap) 1124 return 0; 1125 1126 /* 1127 * Save the original size of the old filesystem, and 1128 * temporarily set the size to be the new size if the new size 1129 * is larger. We need to do this to avoid catching an error 1130 * by the block iterator routines 1131 */ 1132 orig_size = rfs->old_fs->super->s_blocks_count; 1133 if (orig_size < rfs->new_fs->super->s_blocks_count) 1134 rfs->old_fs->super->s_blocks_count = 1135 rfs->new_fs->super->s_blocks_count; 1136 1137 retval = ext2fs_open_inode_scan(rfs->old_fs, 0, &scan); 1138 if (retval) goto errout; 1139 1140 retval = ext2fs_init_dblist(rfs->old_fs, 0); 1141 if (retval) goto errout; 1142 retval = ext2fs_get_array(rfs->old_fs->blocksize, 3, &block_buf); 1143 if (retval) goto errout; 1144 1145 start_to_move = (rfs->new_fs->group_desc_count * 1146 rfs->new_fs->super->s_inodes_per_group); 1147 1148 if (rfs->progress) { 1149 retval = (rfs->progress)(rfs, E2_RSZ_INODE_SCAN_PASS, 1150 0, rfs->old_fs->group_desc_count); 1151 if (retval) 1152 goto errout; 1153 } 1154 ext2fs_set_inode_callback(scan, progress_callback, (void *) rfs); 1155 pb.rfs = rfs; 1156 pb.inode = inode; 1157 pb.error = 0; 1158 new_inode = EXT2_FIRST_INODE(rfs->new_fs->super); 1159 inode_size = EXT2_INODE_SIZE(rfs->new_fs->super); 1160 inode = malloc(inode_size); 1161 if (!inode) { 1162 retval = ENOMEM; 1163 goto errout; 1164 } 1165 /* 1166 * First, copy all of the inodes that need to be moved 1167 * elsewhere in the inode table 1168 */ 1169 while (1) { 1170 retval = ext2fs_get_next_inode_full(scan, &ino, inode, inode_size); 1171 if (retval) goto errout; 1172 if (!ino) 1173 break; 1174 1175 if (inode->i_links_count == 0 && ino != EXT2_RESIZE_INO) 1176 continue; /* inode not in use */ 1177 1178 pb.is_dir = LINUX_S_ISDIR(inode->i_mode); 1179 pb.changed = 0; 1180 1181 if (inode->i_file_acl && rfs->bmap) { 1182 new_block = ext2fs_extent_translate(rfs->bmap, 1183 inode->i_file_acl); 1184 if (new_block) { 1185 inode->i_file_acl = new_block; 1186 retval = ext2fs_write_inode_full(rfs->old_fs, 1187 ino, inode, inode_size); 1188 if (retval) goto errout; 1189 } 1190 } 1191 1192 if (ext2fs_inode_has_valid_blocks(inode) && 1193 (rfs->bmap || pb.is_dir)) { 1194 pb.ino = ino; 1195 retval = ext2fs_block_iterate2(rfs->old_fs, 1196 ino, 0, block_buf, 1197 process_block, &pb); 1198 if (retval) 1199 goto errout; 1200 if (pb.error) { 1201 retval = pb.error; 1202 goto errout; 1203 } 1204 } 1205 1206 if (ino <= start_to_move) 1207 continue; /* Don't need to move it. */ 1208 1209 /* 1210 * Find a new inode 1211 */ 1212 while (1) { 1213 if (!ext2fs_test_inode_bitmap(rfs->new_fs->inode_map, 1214 new_inode)) 1215 break; 1216 new_inode++; 1217 if (new_inode > rfs->new_fs->super->s_inodes_count) { 1218 retval = ENOSPC; 1219 goto errout; 1220 } 1221 } 1222 ext2fs_mark_inode_bitmap(rfs->new_fs->inode_map, new_inode); 1223 if (pb.changed) { 1224 /* Get the new version of the inode */ 1225 retval = ext2fs_read_inode_full(rfs->old_fs, ino, 1226 inode, inode_size); 1227 if (retval) goto errout; 1228 } 1229 inode->i_ctime = time(0); 1230 retval = ext2fs_write_inode_full(rfs->old_fs, new_inode, 1231 inode, inode_size); 1232 if (retval) goto errout; 1233 1234 group = (new_inode-1) / EXT2_INODES_PER_GROUP(rfs->new_fs->super); 1235 if (LINUX_S_ISDIR(inode->i_mode)) 1236 rfs->new_fs->group_desc[group].bg_used_dirs_count++; 1237 1238 #ifdef RESIZE2FS_DEBUG 1239 if (rfs->flags & RESIZE_DEBUG_INODEMAP) 1240 printf("Inode moved %u->%u\n", ino, new_inode); 1241 #endif 1242 if (!rfs->imap) { 1243 retval = ext2fs_create_extent_table(&rfs->imap, 0); 1244 if (retval) 1245 goto errout; 1246 } 1247 ext2fs_add_extent_entry(rfs->imap, ino, new_inode); 1248 } 1249 io_channel_flush(rfs->old_fs->io); 1250 1251 errout: 1252 rfs->old_fs->super->s_blocks_count = orig_size; 1253 if (rfs->bmap) { 1254 ext2fs_free_extent_table(rfs->bmap); 1255 rfs->bmap = 0; 1256 } 1257 if (scan) 1258 ext2fs_close_inode_scan(scan); 1259 if (block_buf) 1260 ext2fs_free_mem(&block_buf); 1261 if (inode) 1262 free(inode); 1263 return retval; 1264 } 1265 1266 /* -------------------------------------------------------------------- 1267 * 1268 * Resize processing, phase 4. 1269 * 1270 * -------------------------------------------------------------------- 1271 */ 1272 1273 struct istruct { 1274 ext2_resize_t rfs; 1275 errcode_t err; 1276 unsigned long max_dirs; 1277 int num; 1278 }; 1279 1280 static int check_and_change_inodes(ext2_ino_t dir, 1281 int entry EXT2FS_ATTR((unused)), 1282 struct ext2_dir_entry *dirent, int offset, 1283 int blocksize EXT2FS_ATTR((unused)), 1284 char *buf EXT2FS_ATTR((unused)), 1285 void *priv_data) 1286 { 1287 struct istruct *is = (struct istruct *) priv_data; 1288 struct ext2_inode inode; 1289 ext2_ino_t new_inode; 1290 errcode_t retval; 1291 1292 if (is->rfs->progress && offset == 0) { 1293 io_channel_flush(is->rfs->old_fs->io); 1294 is->err = (is->rfs->progress)(is->rfs, 1295 E2_RSZ_INODE_REF_UPD_PASS, 1296 ++is->num, is->max_dirs); 1297 if (is->err) 1298 return DIRENT_ABORT; 1299 } 1300 1301 if (!dirent->inode) 1302 return 0; 1303 1304 new_inode = ext2fs_extent_translate(is->rfs->imap, dirent->inode); 1305 1306 if (!new_inode) 1307 return 0; 1308 #ifdef RESIZE2FS_DEBUG 1309 if (is->rfs->flags & RESIZE_DEBUG_INODEMAP) 1310 printf("Inode translate (dir=%u, name=%.*s, %u->%u)\n", 1311 dir, dirent->name_len&0xFF, dirent->name, 1312 dirent->inode, new_inode); 1313 #endif 1314 1315 dirent->inode = new_inode; 1316 1317 /* Update the directory mtime and ctime */ 1318 retval = ext2fs_read_inode(is->rfs->old_fs, dir, &inode); 1319 if (retval == 0) { 1320 inode.i_mtime = inode.i_ctime = time(0); 1321 is->err = ext2fs_write_inode(is->rfs->old_fs, dir, &inode); 1322 if (is->err) 1323 return DIRENT_ABORT; 1324 } 1325 1326 return DIRENT_CHANGED; 1327 } 1328 1329 static errcode_t inode_ref_fix(ext2_resize_t rfs) 1330 { 1331 errcode_t retval; 1332 struct istruct is; 1333 1334 if (!rfs->imap) 1335 return 0; 1336 1337 /* 1338 * Now, we iterate over all of the directories to update the 1339 * inode references 1340 */ 1341 is.num = 0; 1342 is.max_dirs = ext2fs_dblist_count(rfs->old_fs->dblist); 1343 is.rfs = rfs; 1344 is.err = 0; 1345 1346 if (rfs->progress) { 1347 retval = (rfs->progress)(rfs, E2_RSZ_INODE_REF_UPD_PASS, 1348 0, is.max_dirs); 1349 if (retval) 1350 goto errout; 1351 } 1352 1353 retval = ext2fs_dblist_dir_iterate(rfs->old_fs->dblist, 1354 DIRENT_FLAG_INCLUDE_EMPTY, 0, 1355 check_and_change_inodes, &is); 1356 if (retval) 1357 goto errout; 1358 if (is.err) { 1359 retval = is.err; 1360 goto errout; 1361 } 1362 1363 errout: 1364 ext2fs_free_extent_table(rfs->imap); 1365 rfs->imap = 0; 1366 return retval; 1367 } 1368 1369 1370 /* -------------------------------------------------------------------- 1371 * 1372 * Resize processing, phase 5. 1373 * 1374 * In this phase we actually move the inode table around, and then 1375 * update the summary statistics. This is scary, since aborting here 1376 * will potentially scramble the filesystem. (We are moving the 1377 * inode tables around in place, and so the potential for lost data, 1378 * or at the very least scrambling the mapping between filenames and 1379 * inode numbers is very high in case of a power failure here.) 1380 * -------------------------------------------------------------------- 1381 */ 1382 1383 1384 /* 1385 * A very scary routine --- this one moves the inode table around!!! 1386 * 1387 * After this you have to use the rfs->new_fs file handle to read and 1388 * write inodes. 1389 */ 1390 static errcode_t move_itables(ext2_resize_t rfs) 1391 { 1392 int n, num, size, diff; 1393 dgrp_t i, max_groups; 1394 ext2_filsys fs = rfs->new_fs; 1395 char *cp; 1396 blk_t old_blk, new_blk, blk; 1397 errcode_t retval; 1398 int j, to_move, moved; 1399 1400 max_groups = fs->group_desc_count; 1401 if (max_groups > rfs->old_fs->group_desc_count) 1402 max_groups = rfs->old_fs->group_desc_count; 1403 1404 size = fs->blocksize * fs->inode_blocks_per_group; 1405 if (!rfs->itable_buf) { 1406 retval = ext2fs_get_mem(size, &rfs->itable_buf); 1407 if (retval) 1408 return retval; 1409 } 1410 1411 /* 1412 * Figure out how many inode tables we need to move 1413 */ 1414 to_move = moved = 0; 1415 for (i=0; i < max_groups; i++) 1416 if (rfs->old_fs->group_desc[i].bg_inode_table != 1417 fs->group_desc[i].bg_inode_table) 1418 to_move++; 1419 1420 if (to_move == 0) 1421 return 0; 1422 1423 if (rfs->progress) { 1424 retval = rfs->progress(rfs, E2_RSZ_MOVE_ITABLE_PASS, 1425 0, to_move); 1426 if (retval) 1427 goto errout; 1428 } 1429 1430 rfs->old_fs->flags |= EXT2_FLAG_MASTER_SB_ONLY; 1431 1432 for (i=0; i < max_groups; i++) { 1433 old_blk = rfs->old_fs->group_desc[i].bg_inode_table; 1434 new_blk = fs->group_desc[i].bg_inode_table; 1435 diff = new_blk - old_blk; 1436 1437 #ifdef RESIZE2FS_DEBUG 1438 if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE) 1439 printf("Itable move group %d block %u->%u (diff %d)\n", 1440 i, old_blk, new_blk, diff); 1441 #endif 1442 1443 if (!diff) 1444 continue; 1445 1446 retval = io_channel_read_blk(fs->io, old_blk, 1447 fs->inode_blocks_per_group, 1448 rfs->itable_buf); 1449 if (retval) 1450 goto errout; 1451 /* 1452 * The end of the inode table segment often contains 1453 * all zeros, and we're often only moving the inode 1454 * table down a block or two. If so, we can optimize 1455 * things by not rewriting blocks that we know to be zero 1456 * already. 1457 */ 1458 for (cp = rfs->itable_buf+size-1, n=0; n < size; n++, cp--) 1459 if (*cp) 1460 break; 1461 n = n >> EXT2_BLOCK_SIZE_BITS(fs->super); 1462 #ifdef RESIZE2FS_DEBUG 1463 if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE) 1464 printf("%d blocks of zeros...\n", n); 1465 #endif 1466 num = fs->inode_blocks_per_group; 1467 if (n > diff) 1468 num -= n; 1469 1470 retval = io_channel_write_blk(fs->io, new_blk, 1471 num, rfs->itable_buf); 1472 if (retval) { 1473 io_channel_write_blk(fs->io, old_blk, 1474 num, rfs->itable_buf); 1475 goto errout; 1476 } 1477 if (n > diff) { 1478 retval = io_channel_write_blk(fs->io, 1479 old_blk + fs->inode_blocks_per_group, 1480 diff, (rfs->itable_buf + 1481 (fs->inode_blocks_per_group - diff) * 1482 fs->blocksize)); 1483 if (retval) 1484 goto errout; 1485 } 1486 1487 for (blk = rfs->old_fs->group_desc[i].bg_inode_table, j=0; 1488 j < fs->inode_blocks_per_group ; j++, blk++) 1489 ext2fs_unmark_block_bitmap(fs->block_map, blk); 1490 1491 rfs->old_fs->group_desc[i].bg_inode_table = new_blk; 1492 ext2fs_mark_super_dirty(rfs->old_fs); 1493 ext2fs_flush(rfs->old_fs); 1494 1495 if (rfs->progress) { 1496 retval = rfs->progress(rfs, E2_RSZ_MOVE_ITABLE_PASS, 1497 ++moved, to_move); 1498 if (retval) 1499 goto errout; 1500 } 1501 } 1502 mark_table_blocks(fs, fs->block_map); 1503 ext2fs_flush(fs); 1504 #ifdef RESIZE2FS_DEBUG 1505 if (rfs->flags & RESIZE_DEBUG_ITABLEMOVE) 1506 printf("Inode table move finished.\n"); 1507 #endif 1508 return 0; 1509 1510 errout: 1511 return retval; 1512 } 1513 1514 /* 1515 * Fix the resize inode 1516 */ 1517 static errcode_t fix_resize_inode(ext2_filsys fs) 1518 { 1519 struct ext2_inode inode; 1520 errcode_t retval; 1521 char * block_buf; 1522 1523 if (!(fs->super->s_feature_compat & 1524 EXT2_FEATURE_COMPAT_RESIZE_INODE)) 1525 return 0; 1526 1527 retval = ext2fs_get_mem(fs->blocksize, &block_buf); 1528 if (retval) goto errout; 1529 1530 retval = ext2fs_read_inode(fs, EXT2_RESIZE_INO, &inode); 1531 if (retval) goto errout; 1532 1533 inode.i_blocks = fs->blocksize/512; 1534 1535 retval = ext2fs_write_inode(fs, EXT2_RESIZE_INO, &inode); 1536 if (retval) goto errout; 1537 1538 if (!inode.i_block[EXT2_DIND_BLOCK]) { 1539 /* 1540 * Avoid zeroing out block #0; that's rude. This 1541 * should never happen anyway since the filesystem 1542 * should be fsck'ed and we assume it is consistent. 1543 */ 1544 fprintf(stderr, 1545 _("Should never happen: resize inode corrupt!\n")); 1546 exit(1); 1547 } 1548 1549 memset(block_buf, 0, fs->blocksize); 1550 1551 retval = io_channel_write_blk(fs->io, inode.i_block[EXT2_DIND_BLOCK], 1552 1, block_buf); 1553 if (retval) goto errout; 1554 1555 retval = ext2fs_create_resize_inode(fs); 1556 if (retval) 1557 goto errout; 1558 1559 errout: 1560 if (block_buf) 1561 ext2fs_free_mem(&block_buf); 1562 return retval; 1563 } 1564 1565 /* 1566 * Finally, recalculate the summary information 1567 */ 1568 static errcode_t ext2fs_calculate_summary_stats(ext2_filsys fs) 1569 { 1570 blk_t blk; 1571 ext2_ino_t ino; 1572 unsigned int group = 0; 1573 unsigned int count = 0; 1574 int total_free = 0; 1575 int group_free = 0; 1576 1577 /* 1578 * First calculate the block statistics 1579 */ 1580 for (blk = fs->super->s_first_data_block; 1581 blk < fs->super->s_blocks_count; blk++) { 1582 if (!ext2fs_fast_test_block_bitmap(fs->block_map, blk)) { 1583 group_free++; 1584 total_free++; 1585 } 1586 count++; 1587 if ((count == fs->super->s_blocks_per_group) || 1588 (blk == fs->super->s_blocks_count-1)) { 1589 fs->group_desc[group++].bg_free_blocks_count = 1590 group_free; 1591 count = 0; 1592 group_free = 0; 1593 } 1594 } 1595 fs->super->s_free_blocks_count = total_free; 1596 1597 /* 1598 * Next, calculate the inode statistics 1599 */ 1600 group_free = 0; 1601 total_free = 0; 1602 count = 0; 1603 group = 0; 1604 1605 /* Protect loop from wrap-around if s_inodes_count maxed */ 1606 for (ino = 1; ino <= fs->super->s_inodes_count && ino > 0; ino++) { 1607 if (!ext2fs_fast_test_inode_bitmap(fs->inode_map, ino)) { 1608 group_free++; 1609 total_free++; 1610 } 1611 count++; 1612 if ((count == fs->super->s_inodes_per_group) || 1613 (ino == fs->super->s_inodes_count)) { 1614 fs->group_desc[group++].bg_free_inodes_count = 1615 group_free; 1616 count = 0; 1617 group_free = 0; 1618 } 1619 } 1620 fs->super->s_free_inodes_count = total_free; 1621 ext2fs_mark_super_dirty(fs); 1622 return 0; 1623 } 1624
