1/* 2 * Copyright (C) 2010 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16#include "ext4_utils.h" 17#include "make_ext4fs.h" 18#include "ext4_extents.h" 19#include "allocate.h" 20#include "ext4fixup.h" 21 22#include <sparse/sparse.h> 23 24#include <sys/types.h> 25#include <sys/stat.h> 26#include <sys/types.h> 27#include <fcntl.h> 28#include <unistd.h> 29 30#ifndef USE_MINGW 31#include <sys/mman.h> 32#endif 33 34#if defined(__APPLE__) && defined(__MACH__) 35#define lseek64 lseek 36#define off64_t off_t 37#endif 38 39/* The inode block count for a file/directory is in units of 512 byte blocks, 40 * _NOT_ the filesystem block size! 41 */ 42#define INODE_BLOCK_SIZE 512 43 44#define MAX_EXT4_BLOCK_SIZE 4096 45 46/* The two modes the recurse_dir() can be in */ 47#define SANITY_CHECK_PASS 1 48#define MARK_INODE_NUMS 2 49#define UPDATE_INODE_NUMS 3 50 51/* Magic numbers to indicate what state the update process is in */ 52#define MAGIC_STATE_MARKING_INUMS 0x7000151515565512ll 53#define MAGIC_STATE_UPDATING_INUMS 0x6121131211735123ll 54#define MAGIC_STATE_UPDATING_SB 0x15e1715151558477ll 55 56/* Internal state variables corresponding to the magic numbers */ 57#define STATE_UNSET 0 58#define STATE_MARKING_INUMS 1 59#define STATE_UPDATING_INUMS 2 60#define STATE_UPDATING_SB 3 61 62/* Used for automated testing of this programs ability to stop and be restarted wthout error */ 63static int bail_phase = 0; 64static int bail_loc = 0; 65static int bail_count = 0; 66static int count = 0; 67 68/* global flags */ 69static int verbose = 0; 70static int no_write = 0; 71 72static int new_inodes_per_group = 0; 73 74static int no_write_fixup_state = 0; 75 76static int compute_new_inum(unsigned int old_inum) 77{ 78 unsigned int group, offset; 79 80 group = (old_inum - 1) / info.inodes_per_group; 81 offset = (old_inum -1) % info.inodes_per_group; 82 83 return (group * new_inodes_per_group) + offset + 1; 84} 85 86static int get_fs_fixup_state(int fd) 87{ 88 unsigned long long magic; 89 int ret, len; 90 91 if (no_write) { 92 return no_write_fixup_state; 93 } 94 95 lseek64(fd, 0, SEEK_SET); 96 len = read(fd, &magic, sizeof(magic)); 97 if (len != sizeof(magic)) { 98 critical_error("cannot read fixup_state\n"); 99 } 100 101 switch (magic) { 102 case MAGIC_STATE_MARKING_INUMS: 103 ret = STATE_MARKING_INUMS; 104 break; 105 case MAGIC_STATE_UPDATING_INUMS: 106 ret = STATE_UPDATING_INUMS; 107 break; 108 case MAGIC_STATE_UPDATING_SB: 109 ret = STATE_UPDATING_SB; 110 break; 111 default: 112 ret = STATE_UNSET; 113 } 114 return ret; 115} 116 117static int set_fs_fixup_state(int fd, int state) 118{ 119 unsigned long long magic; 120 struct ext4_super_block sb; 121 int len; 122 123 if (no_write) { 124 no_write_fixup_state = state; 125 return 0; 126 } 127 128 switch (state) { 129 case STATE_MARKING_INUMS: 130 magic = MAGIC_STATE_MARKING_INUMS; 131 break; 132 case STATE_UPDATING_INUMS: 133 magic = MAGIC_STATE_UPDATING_INUMS; 134 break; 135 case STATE_UPDATING_SB: 136 magic = MAGIC_STATE_UPDATING_SB; 137 break; 138 case STATE_UNSET: 139 default: 140 magic = 0ll; 141 break; 142 } 143 144 lseek64(fd, 0, SEEK_SET); 145 len = write(fd, &magic, sizeof(magic)); 146 if (len != sizeof(magic)) { 147 critical_error("cannot write fixup_state\n"); 148 } 149 150 read_sb(fd, &sb); 151 if (magic) { 152 /* If we are in the process of updating the filesystem, make it unmountable */ 153 sb.s_desc_size |= 1; 154 } else { 155 /* we are done, so make the filesystem mountable again */ 156 sb.s_desc_size &= ~1; 157 } 158 159 if (!no_write) { 160 write_sb(fd, 1024, &sb); 161 } 162 163 return 0; 164} 165 166static int read_inode(int fd, unsigned int inum, struct ext4_inode *inode) 167{ 168 unsigned int bg_num, bg_offset; 169 off64_t inode_offset; 170 int len; 171 172 bg_num = (inum-1) / info.inodes_per_group; 173 bg_offset = (inum-1) % info.inodes_per_group; 174 175 inode_offset = ((unsigned long long)aux_info.bg_desc[bg_num].bg_inode_table * info.block_size) + 176 (bg_offset * info.inode_size); 177 178 if (lseek64(fd, inode_offset, SEEK_SET) < 0) { 179 critical_error_errno("failed to seek to inode %d\n", inum); 180 } 181 182 len=read(fd, inode, sizeof(*inode)); 183 if (len != sizeof(*inode)) { 184 critical_error_errno("failed to read inode %d\n", inum); 185 } 186 187 return 0; 188} 189 190static int read_block(int fd, unsigned long long block_num, void *block) 191{ 192 off64_t off; 193 unsigned int len; 194 195 off = block_num * info.block_size; 196 197 if (lseek64(fd, off, SEEK_SET) , 0) { 198 critical_error_errno("failed to seek to block %lld\n", block_num); 199 } 200 201 len=read(fd, block, info.block_size); 202 if (len != info.block_size) { 203 critical_error_errno("failed to read block %lld\n", block_num); 204 } 205 206 return 0; 207} 208 209static int write_block(int fd, unsigned long long block_num, void *block) 210{ 211 off64_t off; 212 unsigned int len; 213 214 if (no_write) { 215 return 0; 216 } 217 218 off = block_num * info.block_size; 219 220 if (lseek64(fd, off, SEEK_SET) < 0) { 221 critical_error_errno("failed to seek to block %lld\n", block_num); 222 } 223 224 len=write(fd, block, info.block_size); 225 if (len != info.block_size) { 226 critical_error_errno("failed to write block %lld\n", block_num); 227 } 228 229 return 0; 230} 231 232static void check_inode_bitmap(int fd, unsigned int bg_num) 233{ 234 unsigned int inode_bitmap_block_num; 235 unsigned char block[MAX_EXT4_BLOCK_SIZE]; 236 int i, bitmap_updated = 0; 237 238 /* Using the bg_num, aux_info.bg_desc[], info.inodes_per_group and 239 * new_inodes_per_group, retrieve the inode bitmap, and make sure 240 * the bits between the old and new size are clear 241 */ 242 inode_bitmap_block_num = aux_info.bg_desc[bg_num].bg_inode_bitmap; 243 244 read_block(fd, inode_bitmap_block_num, block); 245 246 for (i = info.inodes_per_group; i < new_inodes_per_group; i++) { 247 if (bitmap_get_bit(block, i)) { 248 bitmap_clear_bit(block, i); 249 bitmap_updated = 1; 250 } 251 } 252 253 if (bitmap_updated) { 254 if (verbose) { 255 printf("Warning: updated inode bitmap for block group %d\n", bg_num); 256 } 257 write_block(fd, inode_bitmap_block_num, block); 258 } 259 260 return; 261} 262 263/* Update the superblock and bgdesc of the specified block group */ 264static int update_superblocks_and_bg_desc(int fd, int state) 265{ 266 off64_t ret; 267 struct ext4_super_block sb; 268 unsigned int num_block_groups, total_new_inodes; 269 unsigned int i; 270 271 272 read_sb(fd, &sb); 273 274 /* Compute how many more inodes are now available */ 275 num_block_groups = DIV_ROUND_UP(aux_info.len_blocks, info.blocks_per_group); 276 total_new_inodes = num_block_groups * (new_inodes_per_group - sb.s_inodes_per_group); 277 278 if (verbose) { 279 printf("created %d additional inodes\n", total_new_inodes); 280 } 281 282 /* Update the free inodes count in each block group descriptor */ 283 for (i = 0; i < num_block_groups; i++) { 284 if (state == STATE_UPDATING_SB) { 285 aux_info.bg_desc[i].bg_free_inodes_count += (new_inodes_per_group - sb.s_inodes_per_group); 286 } 287 check_inode_bitmap(fd, i); 288 } 289 290 /* First some sanity checks */ 291 if ((sb.s_inodes_count + total_new_inodes) != (new_inodes_per_group * num_block_groups)) { 292 critical_error("Failed sanity check on new inode count\n"); 293 } 294 if (new_inodes_per_group % (info.block_size/info.inode_size)) { 295 critical_error("Failed sanity check on new inode per group alignment\n"); 296 } 297 298 /* Update the free inodes count in the superblock */ 299 sb.s_inodes_count += total_new_inodes; 300 sb.s_free_inodes_count += total_new_inodes; 301 sb.s_inodes_per_group = new_inodes_per_group; 302 303 for (i = 0; i < aux_info.groups; i++) { 304 if (ext4_bg_has_super_block(i)) { 305 unsigned int sb_offset; 306 307 if (i == 0) { 308 /* The first superblock is offset by 1K to leave room for boot sectors */ 309 sb_offset = 1024; 310 } else { 311 sb_offset = 0; 312 } 313 314 sb.s_block_group_nr = i; 315 /* Don't write out the backup superblocks with the bit set in the s_desc_size 316 * which prevents the filesystem from mounting. The bit for the primary 317 * superblock will be cleared on the final call to set_fs_fixup_state() */ 318 if (i != 0) { 319 sb.s_desc_size &= ~1; 320 } 321 322 if (!no_write) { 323 write_sb(fd, 324 (unsigned long long)i 325 * info.blocks_per_group * info.block_size 326 + sb_offset, 327 &sb); 328 } 329 330 ret = lseek64(fd, ((unsigned long long)i * info.blocks_per_group * info.block_size) + 331 (info.block_size * (aux_info.first_data_block + 1)), SEEK_SET); 332 if (ret < 0) 333 critical_error_errno("failed to seek to block group descriptors"); 334 335 if (!no_write) { 336 ret = write(fd, aux_info.bg_desc, info.block_size * aux_info.bg_desc_blocks); 337 if (ret < 0) 338 critical_error_errno("failed to write block group descriptors"); 339 if (ret != (int)info.block_size * (int)aux_info.bg_desc_blocks) 340 critical_error("failed to write all of block group descriptors"); 341 } 342 } 343 if ((bail_phase == 4) && ((unsigned int)bail_count == i)) { 344 critical_error("bailing at phase 4\n"); 345 } 346 } 347 348 return 0; 349} 350 351 352static int get_direct_blocks(struct ext4_inode *inode, unsigned long long *block_list, 353 unsigned int *count) 354{ 355 unsigned int i = 0; 356 unsigned int ret = 0; 357 unsigned int sectors_per_block; 358 359 sectors_per_block = info.block_size / INODE_BLOCK_SIZE; 360 while ((i < (inode->i_blocks_lo / sectors_per_block)) && (i < EXT4_NDIR_BLOCKS)) { 361 block_list[i] = inode->i_block[i]; 362 i++; 363 } 364 365 *count += i; 366 367 if ((inode->i_blocks_lo / sectors_per_block) > EXT4_NDIR_BLOCKS) { 368 ret = 1; 369 } 370 371 return ret; 372} 373 374static int get_indirect_blocks(int fd, struct ext4_inode *inode, 375 unsigned long long *block_list, unsigned int *count) 376{ 377 unsigned int i; 378 unsigned int *indirect_block; 379 unsigned int sectors_per_block; 380 381 sectors_per_block = info.block_size / INODE_BLOCK_SIZE; 382 383 indirect_block = (unsigned int *)malloc(info.block_size); 384 if (indirect_block == 0) { 385 critical_error("failed to allocate memory for indirect_block\n"); 386 } 387 388 read_block(fd, inode->i_block[EXT4_NDIR_BLOCKS], indirect_block); 389 390 for(i = 0; i < (inode->i_blocks_lo / sectors_per_block - EXT4_NDIR_BLOCKS); i++) { 391 block_list[EXT4_NDIR_BLOCKS+i] = indirect_block[i]; 392 } 393 394 *count += i; 395 396 free(indirect_block); 397 398 return 0; 399} 400 401static int get_block_list_indirect(int fd, struct ext4_inode *inode, unsigned long long *block_list) 402{ 403 unsigned int count=0; 404 405 if (get_direct_blocks(inode, block_list, &count)) { 406 get_indirect_blocks(fd, inode, block_list, &count); 407 } 408 409 return count; 410} 411 412static int get_extent_ents(struct ext4_extent_header *ext_hdr, unsigned long long *block_list) 413{ 414 int i, j; 415 struct ext4_extent *extent; 416 off64_t fs_block_num; 417 418 if (ext_hdr->eh_depth != 0) { 419 critical_error("get_extent_ents called with eh_depth != 0\n"); 420 } 421 422 /* The extent entries immediately follow the header, so add 1 to the pointer 423 * and cast it to an extent pointer. 424 */ 425 extent = (struct ext4_extent *)(ext_hdr + 1); 426 427 for (i = 0; i < ext_hdr->eh_entries; i++) { 428 fs_block_num = ((off64_t)extent->ee_start_hi << 32) | extent->ee_start_lo; 429 for (j = 0; j < extent->ee_len; j++) { 430 block_list[extent->ee_block+j] = fs_block_num+j; 431 } 432 extent++; 433 } 434 435 return 0; 436} 437 438static int get_extent_idx(int fd, struct ext4_extent_header *ext_hdr, unsigned long long *block_list) 439{ 440 int i; 441 struct ext4_extent_idx *extent_idx; 442 struct ext4_extent_header *tmp_ext_hdr; 443 off64_t fs_block_num; 444 unsigned char block[MAX_EXT4_BLOCK_SIZE]; 445 446 /* Sanity check */ 447 if (ext_hdr->eh_depth == 0) { 448 critical_error("get_extent_idx called with eh_depth == 0\n"); 449 } 450 451 /* The extent entries immediately follow the header, so add 1 to the pointer 452 * and cast it to an extent pointer. 453 */ 454 extent_idx = (struct ext4_extent_idx *)(ext_hdr + 1); 455 456 for (i = 0; i < ext_hdr->eh_entries; i++) { 457 fs_block_num = ((off64_t)extent_idx->ei_leaf_hi << 32) | extent_idx->ei_leaf_lo; 458 read_block(fd, fs_block_num, block); 459 tmp_ext_hdr = (struct ext4_extent_header *)block; 460 461 if (tmp_ext_hdr->eh_depth == 0) { 462 get_extent_ents(tmp_ext_hdr, block_list); /* leaf node, fill in block_list */ 463 } else { 464 get_extent_idx(fd, tmp_ext_hdr, block_list); /* recurse down the tree */ 465 } 466 } 467 468 return 0; 469} 470 471static int get_block_list_extents(int fd, struct ext4_inode *inode, unsigned long long *block_list) 472{ 473 struct ext4_extent_header *extent_hdr; 474 475 extent_hdr = (struct ext4_extent_header *)inode->i_block; 476 477 if (extent_hdr->eh_magic != EXT4_EXT_MAGIC) { 478 critical_error("extent header has unexpected magic value 0x%4.4x\n", 479 extent_hdr->eh_magic); 480 } 481 482 if (extent_hdr->eh_depth == 0) { 483 get_extent_ents((struct ext4_extent_header *)inode->i_block, block_list); 484 return 0; 485 } 486 487 get_extent_idx(fd, (struct ext4_extent_header *)inode->i_block, block_list); 488 489 return 0; 490} 491 492static int is_entry_dir(int fd, struct ext4_dir_entry_2 *dirp, int pass) 493{ 494 struct ext4_inode inode; 495 int ret = 0; 496 497 if (dirp->file_type == EXT4_FT_DIR) { 498 ret = 1; 499 } else if (dirp->file_type == EXT4_FT_UNKNOWN) { 500 /* Somebody was too lazy to fill in the dir entry, 501 * so we have to go fetch it from the inode. Grrr. 502 */ 503 /* if UPDATE_INODE_NUMS pass and the inode high bit is not 504 * set return false so we don't recurse down the tree that is 505 * already updated. Otherwise, fetch inode, and return answer. 506 */ 507 if ((pass == UPDATE_INODE_NUMS) && !(dirp->inode & 0x80000000)) { 508 ret = 0; 509 } else { 510 read_inode(fd, (dirp->inode & 0x7fffffff), &inode); 511 if (S_ISDIR(inode.i_mode)) { 512 ret = 1; 513 } 514 } 515 } 516 517 return ret; 518} 519 520static int recurse_dir(int fd, struct ext4_inode *inode, char *dirbuf, int dirsize, int mode) 521{ 522 unsigned long long *block_list; 523 unsigned int num_blocks; 524 struct ext4_dir_entry_2 *dirp, *prev_dirp = 0; 525 char name[256]; 526 unsigned int i, leftover_space, is_dir; 527 struct ext4_inode tmp_inode; 528 int tmp_dirsize; 529 char *tmp_dirbuf; 530 531 switch (mode) { 532 case SANITY_CHECK_PASS: 533 case MARK_INODE_NUMS: 534 case UPDATE_INODE_NUMS: 535 break; 536 default: 537 critical_error("recurse_dir() called witn unknown mode!\n"); 538 } 539 540 if (dirsize % info.block_size) { 541 critical_error("dirsize %d not a multiple of block_size %d. This is unexpected!\n", 542 dirsize, info.block_size); 543 } 544 545 num_blocks = dirsize / info.block_size; 546 547 block_list = malloc((num_blocks + 1) * sizeof(*block_list)); 548 if (block_list == 0) { 549 critical_error("failed to allocate memory for block_list\n"); 550 } 551 552 if (inode->i_flags & EXT4_EXTENTS_FL) { 553 get_block_list_extents(fd, inode, block_list); 554 } else { 555 /* A directory that requires doubly or triply indirect blocks in huge indeed, 556 * and will almost certainly not exist, especially since make_ext4fs only creates 557 * directories with extents, and the kernel will too, but check to make sure the 558 * directory is not that big and give an error if so. Our limit is 12 direct blocks, 559 * plus block_size/4 singly indirect blocks, which for a filesystem with 4K blocks 560 * is a directory 1036 blocks long, or 4,243,456 bytes long! Assuming an average 561 * filename length of 20 (which I think is generous) thats 20 + 8 bytes overhead 562 * per entry, or 151,552 entries in the directory! 563 */ 564 if (num_blocks > (info.block_size / 4 + EXT4_NDIR_BLOCKS)) { 565 critical_error("Non-extent based directory is too big!\n"); 566 } 567 get_block_list_indirect(fd, inode, block_list); 568 } 569 570 /* Read in all the blocks for this directory */ 571 for (i = 0; i < num_blocks; i++) { 572 read_block(fd, block_list[i], dirbuf + (i * info.block_size)); 573 } 574 575 dirp = (struct ext4_dir_entry_2 *)dirbuf; 576 while (dirp < (struct ext4_dir_entry_2 *)(dirbuf + dirsize)) { 577 count++; 578 leftover_space = (char *)(dirbuf + dirsize) - (char *)dirp; 579 if (((mode == SANITY_CHECK_PASS) || (mode == UPDATE_INODE_NUMS)) && 580 (leftover_space <= 8) && prev_dirp) { 581 /* This is a bug in an older version of make_ext4fs, where it 582 * didn't properly include the rest of the block in rec_len. 583 * Update rec_len on the previous entry to include the rest of 584 * the block and exit the loop. 585 */ 586 if (verbose) { 587 printf("fixing up short rec_len for diretory entry for %s\n", name); 588 } 589 prev_dirp->rec_len += leftover_space; 590 break; 591 } 592 593 if (dirp->inode == 0) { 594 /* This is the last entry in the directory */ 595 break; 596 } 597 598 strncpy(name, dirp->name, dirp->name_len); 599 name[dirp->name_len]='\0'; 600 601 /* Only recurse on pass UPDATE_INODE_NUMS if the high bit is set. 602 * Otherwise, this inode entry has already been updated 603 * and we'll do the wrong thing. Also don't recurse on . or .., 604 * and certainly not on non-directories! 605 */ 606 /* Hrm, looks like filesystems made by fastboot on stingray set the file_type 607 * flag, but the lost+found directory has the type set to Unknown, which 608 * seems to imply I need to read the inode and get it. 609 */ 610 is_dir = is_entry_dir(fd, dirp, mode); 611 if ( is_dir && (strcmp(name, ".") && strcmp(name, "..")) && 612 ((mode == SANITY_CHECK_PASS) || (mode == MARK_INODE_NUMS) || 613 ((mode == UPDATE_INODE_NUMS) && (dirp->inode & 0x80000000))) ) { 614 /* A directory! Recurse! */ 615 read_inode(fd, dirp->inode & 0x7fffffff, &tmp_inode); 616 617 if (!S_ISDIR(tmp_inode.i_mode)) { 618 critical_error("inode %d for name %s does not point to a directory\n", 619 dirp->inode & 0x7fffffff, name); 620 } 621 if (verbose) { 622 printf("inode %d %s use extents\n", dirp->inode & 0x7fffffff, 623 (tmp_inode.i_flags & EXT4_EXTENTS_FL) ? "does" : "does not"); 624 } 625 626 tmp_dirsize = tmp_inode.i_blocks_lo * INODE_BLOCK_SIZE; 627 if (verbose) { 628 printf("dir size = %d bytes\n", tmp_dirsize); 629 } 630 631 tmp_dirbuf = malloc(tmp_dirsize); 632 if (tmp_dirbuf == 0) { 633 critical_error("failed to allocate memory for tmp_dirbuf\n"); 634 } 635 636 recurse_dir(fd, &tmp_inode, tmp_dirbuf, tmp_dirsize, mode); 637 638 free(tmp_dirbuf); 639 } 640 641 if (verbose) { 642 if (is_dir) { 643 printf("Directory %s\n", name); 644 } else { 645 printf("Non-directory %s\n", name); 646 } 647 } 648 649 /* Process entry based on current mode. Either set high bit or change inode number */ 650 if (mode == MARK_INODE_NUMS) { 651 dirp->inode |= 0x80000000; 652 } else if (mode == UPDATE_INODE_NUMS) { 653 if (dirp->inode & 0x80000000) { 654 dirp->inode = compute_new_inum(dirp->inode & 0x7fffffff); 655 } 656 } 657 658 if ((bail_phase == mode) && (bail_loc == 1) && (bail_count == count)) { 659 critical_error("Bailing at phase %d, loc 1 and count %d\n", mode, count); 660 } 661 662 /* Point dirp at the next entry */ 663 prev_dirp = dirp; 664 dirp = (struct ext4_dir_entry_2*)((char *)dirp + dirp->rec_len); 665 } 666 667 /* Write out all the blocks for this directory */ 668 for (i = 0; i < num_blocks; i++) { 669 write_block(fd, block_list[i], dirbuf + (i * info.block_size)); 670 if ((bail_phase == mode) && (bail_loc == 2) && (bail_count <= count)) { 671 critical_error("Bailing at phase %d, loc 2 and count %d\n", mode, count); 672 } 673 } 674 675 free(block_list); 676 677 return 0; 678} 679 680int ext4fixup(char *fsdev) 681{ 682 return ext4fixup_internal(fsdev, 0, 0, 0, 0, 0); 683} 684 685int ext4fixup_internal(char *fsdev, int v_flag, int n_flag, 686 int stop_phase, int stop_loc, int stop_count) 687{ 688 int fd; 689 struct ext4_inode root_inode; 690 unsigned int dirsize; 691 char *dirbuf; 692 693 if (setjmp(setjmp_env)) 694 return EXIT_FAILURE; /* Handle a call to longjmp() */ 695 696 verbose = v_flag; 697 no_write = n_flag; 698 699 bail_phase = stop_phase; 700 bail_loc = stop_loc; 701 bail_count = stop_count; 702 703 fd = open(fsdev, O_RDWR); 704 705 if (fd < 0) 706 critical_error_errno("failed to open filesystem image"); 707 708 read_ext(fd, verbose); 709 710 if (info.feat_incompat & EXT4_FEATURE_INCOMPAT_RECOVER) { 711 critical_error("Filesystem needs recovery first, mount and unmount to do that\n"); 712 } 713 714 /* Clear the low bit which is set while this tool is in progress. 715 * If the tool crashes, it will still be set when we restart. 716 * The low bit is set to make the filesystem unmountable while 717 * it is being fixed up. Also allow 0, which means the old ext2 718 * size is in use. 719 */ 720 if (((aux_info.sb->s_desc_size & ~1) != sizeof(struct ext2_group_desc)) && 721 ((aux_info.sb->s_desc_size & ~1) != 0)) 722 critical_error("error: bg_desc_size != sizeof(struct ext2_group_desc)\n"); 723 724 if ((info.feat_incompat & EXT4_FEATURE_INCOMPAT_FILETYPE) == 0) { 725 critical_error("Expected filesystem to have filetype flag set\n"); 726 } 727 728#if 0 // If we have to fix the directory rec_len issue, we can't use this check 729 /* Check to see if the inodes/group is copacetic */ 730 if (info.inodes_per_blockgroup % (info.block_size/info.inode_size) == 0) { 731 /* This filesystem has either already been updated, or was 732 * made correctly. 733 */ 734 if (verbose) { 735 printf("%s: filesystem correct, no work to do\n", me); 736 } 737 exit(0); 738 } 739#endif 740 741 /* Compute what the new value of inodes_per_blockgroup will be when we're done */ 742 new_inodes_per_group=EXT4_ALIGN(info.inodes_per_group,(info.block_size/info.inode_size)); 743 744 read_inode(fd, EXT4_ROOT_INO, &root_inode); 745 746 if (!S_ISDIR(root_inode.i_mode)) { 747 critical_error("root inode %d does not point to a directory\n", EXT4_ROOT_INO); 748 } 749 if (verbose) { 750 printf("inode %d %s use extents\n", EXT4_ROOT_INO, 751 (root_inode.i_flags & EXT4_EXTENTS_FL) ? "does" : "does not"); 752 } 753 754 dirsize = root_inode.i_blocks_lo * INODE_BLOCK_SIZE; 755 if (verbose) { 756 printf("root dir size = %d bytes\n", dirsize); 757 } 758 759 dirbuf = malloc(dirsize); 760 if (dirbuf == 0) { 761 critical_error("failed to allocate memory for dirbuf\n"); 762 } 763 764 /* Perform a sanity check pass first, try to catch any errors that will occur 765 * before we actually change anything, so we don't leave a filesystem in a 766 * corrupted, unrecoverable state. Set no_write, make it quiet, and do a recurse 767 * pass and a update_superblock pass. Set flags back to requested state when done. 768 * Only perform sanity check if the state is unset. If the state is _NOT_ unset, 769 * then the tool has already been run and interrupted, and it presumably ran and 770 * passed sanity checked before it got interrupted. It is _NOT_ safe to run sanity 771 * check if state is unset because it assumes inodes are to be computed using the 772 * old inodes/group, but some inode numbers may be updated to the new number. 773 */ 774 if (get_fs_fixup_state(fd) == STATE_UNSET) { 775 verbose = 0; 776 no_write = 1; 777 recurse_dir(fd, &root_inode, dirbuf, dirsize, SANITY_CHECK_PASS); 778 update_superblocks_and_bg_desc(fd, STATE_UNSET); 779 verbose = v_flag; 780 no_write = n_flag; 781 782 set_fs_fixup_state(fd, STATE_MARKING_INUMS); 783 } 784 785 if (get_fs_fixup_state(fd) == STATE_MARKING_INUMS) { 786 count = 0; /* Reset debugging counter */ 787 if (!recurse_dir(fd, &root_inode, dirbuf, dirsize, MARK_INODE_NUMS)) { 788 set_fs_fixup_state(fd, STATE_UPDATING_INUMS); 789 } 790 } 791 792 if (get_fs_fixup_state(fd) == STATE_UPDATING_INUMS) { 793 count = 0; /* Reset debugging counter */ 794 if (!recurse_dir(fd, &root_inode, dirbuf, dirsize, UPDATE_INODE_NUMS)) { 795 set_fs_fixup_state(fd, STATE_UPDATING_SB); 796 } 797 } 798 799 if (get_fs_fixup_state(fd) == STATE_UPDATING_SB) { 800 /* set the new inodes/blockgroup number, 801 * and sets the state back to 0. 802 */ 803 if (!update_superblocks_and_bg_desc(fd, STATE_UPDATING_SB)) { 804 set_fs_fixup_state(fd, STATE_UNSET); 805 } 806 } 807 808 close(fd); 809 810 return 0; 811} 812