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 17#include "ext4fixup.h" 18 19#ifndef _LARGEFILE64_SOURCE 20#define _LARGEFILE64_SOURCE 1 21#endif 22 23#include <fcntl.h> 24#include <sys/stat.h> 25#include <sys/types.h> 26#include <unistd.h> 27 28#include <sparse/sparse.h> 29 30#include "allocate.h" 31#include "ext4_utils/ext4_extents.h" 32#include "ext4_utils/ext4_utils.h" 33#include "ext4_utils/make_ext4fs.h" 34 35#ifndef _WIN32 36#include <sys/mman.h> 37#endif 38 39#if defined(__APPLE__) && defined(__MACH__) 40#define lseek64 lseek 41#define off64_t off_t 42#endif 43 44/* The inode block count for a file/directory is in units of 512 byte blocks, 45 * _NOT_ the filesystem block size! 46 */ 47#define INODE_BLOCK_SIZE 512 48 49#define MAX_EXT4_BLOCK_SIZE 4096 50 51/* The two modes the recurse_dir() can be in */ 52#define SANITY_CHECK_PASS 1 53#define MARK_INODE_NUMS 2 54#define UPDATE_INODE_NUMS 3 55 56/* Magic numbers to indicate what state the update process is in */ 57#define MAGIC_STATE_MARKING_INUMS 0x7000151515565512ll 58#define MAGIC_STATE_UPDATING_INUMS 0x6121131211735123ll 59#define MAGIC_STATE_UPDATING_SB 0x15e1715151558477ll 60 61/* Internal state variables corresponding to the magic numbers */ 62#define STATE_UNSET 0 63#define STATE_MARKING_INUMS 1 64#define STATE_UPDATING_INUMS 2 65#define STATE_UPDATING_SB 3 66 67/* Used for automated testing of this programs ability to stop and be restarted wthout error */ 68static int bail_phase = 0; 69static int bail_loc = 0; 70static int bail_count = 0; 71static int count = 0; 72 73/* global flags */ 74static int verbose = 0; 75static int no_write = 0; 76 77static int new_inodes_per_group = 0; 78 79static int no_write_fixup_state = 0; 80 81static int compute_new_inum(unsigned int old_inum) 82{ 83 unsigned int group, offset; 84 85 group = (old_inum - 1) / info.inodes_per_group; 86 offset = (old_inum -1) % info.inodes_per_group; 87 88 return (group * new_inodes_per_group) + offset + 1; 89} 90 91static int get_fs_fixup_state(int fd) 92{ 93 unsigned long long magic; 94 int ret, len; 95 96 if (no_write) { 97 return no_write_fixup_state; 98 } 99 100 lseek64(fd, 0, SEEK_SET); 101 len = read(fd, &magic, sizeof(magic)); 102 if (len != sizeof(magic)) { 103 critical_error("cannot read fixup_state\n"); 104 } 105 106 switch (magic) { 107 case MAGIC_STATE_MARKING_INUMS: 108 ret = STATE_MARKING_INUMS; 109 break; 110 case MAGIC_STATE_UPDATING_INUMS: 111 ret = STATE_UPDATING_INUMS; 112 break; 113 case MAGIC_STATE_UPDATING_SB: 114 ret = STATE_UPDATING_SB; 115 break; 116 default: 117 ret = STATE_UNSET; 118 } 119 return ret; 120} 121 122static int set_fs_fixup_state(int fd, int state) 123{ 124 unsigned long long magic; 125 struct ext4_super_block sb; 126 int len; 127 128 if (no_write) { 129 no_write_fixup_state = state; 130 return 0; 131 } 132 133 switch (state) { 134 case STATE_MARKING_INUMS: 135 magic = MAGIC_STATE_MARKING_INUMS; 136 break; 137 case STATE_UPDATING_INUMS: 138 magic = MAGIC_STATE_UPDATING_INUMS; 139 break; 140 case STATE_UPDATING_SB: 141 magic = MAGIC_STATE_UPDATING_SB; 142 break; 143 case STATE_UNSET: 144 default: 145 magic = 0ll; 146 break; 147 } 148 149 lseek64(fd, 0, SEEK_SET); 150 len = write(fd, &magic, sizeof(magic)); 151 if (len != sizeof(magic)) { 152 critical_error("cannot write fixup_state\n"); 153 } 154 155 read_sb(fd, &sb); 156 if (magic) { 157 /* If we are in the process of updating the filesystem, make it unmountable */ 158 sb.s_desc_size |= 1; 159 } else { 160 /* we are done, so make the filesystem mountable again */ 161 sb.s_desc_size &= ~1; 162 } 163 164 if (!no_write) { 165 write_sb(fd, 1024, &sb); 166 } 167 168 return 0; 169} 170 171static int read_inode(int fd, unsigned int inum, struct ext4_inode *inode) 172{ 173 unsigned int bg_num, bg_offset; 174 off64_t inode_offset; 175 int len; 176 177 bg_num = (inum-1) / info.inodes_per_group; 178 bg_offset = (inum-1) % info.inodes_per_group; 179 180 inode_offset = ((unsigned long long)aux_info.bg_desc[bg_num].bg_inode_table * info.block_size) + 181 (bg_offset * info.inode_size); 182 183 if (lseek64(fd, inode_offset, SEEK_SET) < 0) { 184 critical_error_errno("failed to seek to inode %d\n", inum); 185 } 186 187 len=read(fd, inode, sizeof(*inode)); 188 if (len != sizeof(*inode)) { 189 critical_error_errno("failed to read inode %d\n", inum); 190 } 191 192 return 0; 193} 194 195static int read_block(int fd, unsigned long long block_num, void *block) 196{ 197 off64_t off; 198 unsigned int len; 199 200 off = block_num * info.block_size; 201 202 if (lseek64(fd, off, SEEK_SET) , 0) { 203 critical_error_errno("failed to seek to block %lld\n", block_num); 204 } 205 206 len=read(fd, block, info.block_size); 207 if (len != info.block_size) { 208 critical_error_errno("failed to read block %lld\n", block_num); 209 } 210 211 return 0; 212} 213 214static int write_block(int fd, unsigned long long block_num, void *block) 215{ 216 off64_t off; 217 unsigned int len; 218 219 if (no_write) { 220 return 0; 221 } 222 223 off = block_num * info.block_size; 224 225 if (lseek64(fd, off, SEEK_SET) < 0) { 226 critical_error_errno("failed to seek to block %lld\n", block_num); 227 } 228 229 len=write(fd, block, info.block_size); 230 if (len != info.block_size) { 231 critical_error_errno("failed to write block %lld\n", block_num); 232 } 233 234 return 0; 235} 236 237static void check_inode_bitmap(int fd, unsigned int bg_num) 238{ 239 unsigned int inode_bitmap_block_num; 240 unsigned char block[MAX_EXT4_BLOCK_SIZE]; 241 int i, bitmap_updated = 0; 242 243 /* Using the bg_num, aux_info.bg_desc[], info.inodes_per_group and 244 * new_inodes_per_group, retrieve the inode bitmap, and make sure 245 * the bits between the old and new size are clear 246 */ 247 inode_bitmap_block_num = aux_info.bg_desc[bg_num].bg_inode_bitmap; 248 249 read_block(fd, inode_bitmap_block_num, block); 250 251 for (i = info.inodes_per_group; i < new_inodes_per_group; i++) { 252 if (bitmap_get_bit(block, i)) { 253 bitmap_clear_bit(block, i); 254 bitmap_updated = 1; 255 } 256 } 257 258 if (bitmap_updated) { 259 if (verbose) { 260 printf("Warning: updated inode bitmap for block group %d\n", bg_num); 261 } 262 write_block(fd, inode_bitmap_block_num, block); 263 } 264 265 return; 266} 267 268/* Update the superblock and bgdesc of the specified block group */ 269static int update_superblocks_and_bg_desc(int fd, int state) 270{ 271 off64_t ret; 272 struct ext4_super_block sb; 273 unsigned int num_block_groups, total_new_inodes; 274 unsigned int i; 275 276 277 read_sb(fd, &sb); 278 279 /* Compute how many more inodes are now available */ 280 num_block_groups = DIV_ROUND_UP(aux_info.len_blocks, info.blocks_per_group); 281 total_new_inodes = num_block_groups * (new_inodes_per_group - sb.s_inodes_per_group); 282 283 if (verbose) { 284 printf("created %d additional inodes\n", total_new_inodes); 285 } 286 287 /* Update the free inodes count in each block group descriptor */ 288 for (i = 0; i < num_block_groups; i++) { 289 if (state == STATE_UPDATING_SB) { 290 aux_info.bg_desc[i].bg_free_inodes_count += (new_inodes_per_group - sb.s_inodes_per_group); 291 } 292 check_inode_bitmap(fd, i); 293 } 294 295 /* First some sanity checks */ 296 if ((sb.s_inodes_count + total_new_inodes) != (new_inodes_per_group * num_block_groups)) { 297 critical_error("Failed sanity check on new inode count\n"); 298 } 299 if (new_inodes_per_group % (info.block_size/info.inode_size)) { 300 critical_error("Failed sanity check on new inode per group alignment\n"); 301 } 302 303 /* Update the free inodes count in the superblock */ 304 sb.s_inodes_count += total_new_inodes; 305 sb.s_free_inodes_count += total_new_inodes; 306 sb.s_inodes_per_group = new_inodes_per_group; 307 308 for (i = 0; i < aux_info.groups; i++) { 309 if (ext4_bg_has_super_block(i)) { 310 unsigned int sb_offset; 311 312 if (i == 0) { 313 /* The first superblock is offset by 1K to leave room for boot sectors */ 314 sb_offset = 1024; 315 } else { 316 sb_offset = 0; 317 } 318 319 sb.s_block_group_nr = i; 320 /* Don't write out the backup superblocks with the bit set in the s_desc_size 321 * which prevents the filesystem from mounting. The bit for the primary 322 * superblock will be cleared on the final call to set_fs_fixup_state() */ 323 if (i != 0) { 324 sb.s_desc_size &= ~1; 325 } 326 327 if (!no_write) { 328 write_sb(fd, 329 (unsigned long long)i 330 * info.blocks_per_group * info.block_size 331 + sb_offset, 332 &sb); 333 } 334 335 ret = lseek64(fd, ((unsigned long long)i * info.blocks_per_group * info.block_size) + 336 (info.block_size * (aux_info.first_data_block + 1)), SEEK_SET); 337 if (ret < 0) 338 critical_error_errno("failed to seek to block group descriptors"); 339 340 if (!no_write) { 341 ret = write(fd, aux_info.bg_desc, info.block_size * aux_info.bg_desc_blocks); 342 if (ret < 0) 343 critical_error_errno("failed to write block group descriptors"); 344 if (ret != (int)info.block_size * (int)aux_info.bg_desc_blocks) 345 critical_error("failed to write all of block group descriptors"); 346 } 347 } 348 if ((bail_phase == 4) && ((unsigned int)bail_count == i)) { 349 critical_error("bailing at phase 4\n"); 350 } 351 } 352 353 return 0; 354} 355 356 357static int get_direct_blocks(struct ext4_inode *inode, unsigned long long *block_list, 358 unsigned int *count) 359{ 360 unsigned int i = 0; 361 unsigned int ret = 0; 362 unsigned int sectors_per_block; 363 364 sectors_per_block = info.block_size / INODE_BLOCK_SIZE; 365 while ((i < (inode->i_blocks_lo / sectors_per_block)) && (i < EXT4_NDIR_BLOCKS)) { 366 block_list[i] = inode->i_block[i]; 367 i++; 368 } 369 370 *count += i; 371 372 if ((inode->i_blocks_lo / sectors_per_block) > EXT4_NDIR_BLOCKS) { 373 ret = 1; 374 } 375 376 return ret; 377} 378 379static int get_indirect_blocks(int fd, struct ext4_inode *inode, 380 unsigned long long *block_list, unsigned int *count) 381{ 382 unsigned int i; 383 unsigned int *indirect_block; 384 unsigned int sectors_per_block; 385 386 sectors_per_block = info.block_size / INODE_BLOCK_SIZE; 387 388 indirect_block = (unsigned int *)malloc(info.block_size); 389 if (indirect_block == 0) { 390 critical_error("failed to allocate memory for indirect_block\n"); 391 } 392 393 read_block(fd, inode->i_block[EXT4_NDIR_BLOCKS], indirect_block); 394 395 for(i = 0; i < (inode->i_blocks_lo / sectors_per_block - EXT4_NDIR_BLOCKS); i++) { 396 block_list[EXT4_NDIR_BLOCKS+i] = indirect_block[i]; 397 } 398 399 *count += i; 400 401 free(indirect_block); 402 403 return 0; 404} 405 406static int get_block_list_indirect(int fd, struct ext4_inode *inode, unsigned long long *block_list) 407{ 408 unsigned int count=0; 409 410 if (get_direct_blocks(inode, block_list, &count)) { 411 get_indirect_blocks(fd, inode, block_list, &count); 412 } 413 414 return count; 415} 416 417static int get_extent_ents(struct ext4_extent_header *ext_hdr, unsigned long long *block_list) 418{ 419 int i, j; 420 struct ext4_extent *extent; 421 off64_t fs_block_num; 422 423 if (ext_hdr->eh_depth != 0) { 424 critical_error("get_extent_ents called with eh_depth != 0\n"); 425 } 426 427 /* The extent entries immediately follow the header, so add 1 to the pointer 428 * and cast it to an extent pointer. 429 */ 430 extent = (struct ext4_extent *)(ext_hdr + 1); 431 432 for (i = 0; i < ext_hdr->eh_entries; i++) { 433 fs_block_num = ((off64_t)extent->ee_start_hi << 32) | extent->ee_start_lo; 434 for (j = 0; j < extent->ee_len; j++) { 435 block_list[extent->ee_block+j] = fs_block_num+j; 436 } 437 extent++; 438 } 439 440 return 0; 441} 442 443static int get_extent_idx(int fd, struct ext4_extent_header *ext_hdr, unsigned long long *block_list) 444{ 445 int i; 446 struct ext4_extent_idx *extent_idx; 447 struct ext4_extent_header *tmp_ext_hdr; 448 off64_t fs_block_num; 449 unsigned char block[MAX_EXT4_BLOCK_SIZE]; 450 451 /* Sanity check */ 452 if (ext_hdr->eh_depth == 0) { 453 critical_error("get_extent_idx called with eh_depth == 0\n"); 454 } 455 456 /* The extent entries immediately follow the header, so add 1 to the pointer 457 * and cast it to an extent pointer. 458 */ 459 extent_idx = (struct ext4_extent_idx *)(ext_hdr + 1); 460 461 for (i = 0; i < ext_hdr->eh_entries; i++) { 462 fs_block_num = ((off64_t)extent_idx->ei_leaf_hi << 32) | extent_idx->ei_leaf_lo; 463 read_block(fd, fs_block_num, block); 464 tmp_ext_hdr = (struct ext4_extent_header *)block; 465 466 if (tmp_ext_hdr->eh_depth == 0) { 467 get_extent_ents(tmp_ext_hdr, block_list); /* leaf node, fill in block_list */ 468 } else { 469 get_extent_idx(fd, tmp_ext_hdr, block_list); /* recurse down the tree */ 470 } 471 } 472 473 return 0; 474} 475 476static int get_block_list_extents(int fd, struct ext4_inode *inode, unsigned long long *block_list) 477{ 478 struct ext4_extent_header *extent_hdr; 479 480 extent_hdr = (struct ext4_extent_header *)inode->i_block; 481 482 if (extent_hdr->eh_magic != EXT4_EXT_MAGIC) { 483 critical_error("extent header has unexpected magic value 0x%4.4x\n", 484 extent_hdr->eh_magic); 485 } 486 487 if (extent_hdr->eh_depth == 0) { 488 get_extent_ents((struct ext4_extent_header *)inode->i_block, block_list); 489 return 0; 490 } 491 492 get_extent_idx(fd, (struct ext4_extent_header *)inode->i_block, block_list); 493 494 return 0; 495} 496 497static int is_entry_dir(int fd, struct ext4_dir_entry_2 *dirp, int pass) 498{ 499 struct ext4_inode inode; 500 int ret = 0; 501 502 if (dirp->file_type == EXT4_FT_DIR) { 503 ret = 1; 504 } else if (dirp->file_type == EXT4_FT_UNKNOWN) { 505 /* Somebody was too lazy to fill in the dir entry, 506 * so we have to go fetch it from the inode. Grrr. 507 */ 508 /* if UPDATE_INODE_NUMS pass and the inode high bit is not 509 * set return false so we don't recurse down the tree that is 510 * already updated. Otherwise, fetch inode, and return answer. 511 */ 512 if ((pass == UPDATE_INODE_NUMS) && !(dirp->inode & 0x80000000)) { 513 ret = 0; 514 } else { 515 read_inode(fd, (dirp->inode & 0x7fffffff), &inode); 516 if (S_ISDIR(inode.i_mode)) { 517 ret = 1; 518 } 519 } 520 } 521 522 return ret; 523} 524 525static int recurse_dir(int fd, struct ext4_inode *inode, char *dirbuf, int dirsize, int mode) 526{ 527 unsigned long long *block_list; 528 unsigned int num_blocks; 529 struct ext4_dir_entry_2 *dirp, *prev_dirp = 0; 530 char name[256]; 531 unsigned int i, leftover_space, is_dir; 532 struct ext4_inode tmp_inode; 533 int tmp_dirsize; 534 char *tmp_dirbuf; 535 536 switch (mode) { 537 case SANITY_CHECK_PASS: 538 case MARK_INODE_NUMS: 539 case UPDATE_INODE_NUMS: 540 break; 541 default: 542 critical_error("recurse_dir() called witn unknown mode!\n"); 543 } 544 545 if (dirsize % info.block_size) { 546 critical_error("dirsize %d not a multiple of block_size %d. This is unexpected!\n", 547 dirsize, info.block_size); 548 } 549 550 num_blocks = dirsize / info.block_size; 551 552 block_list = malloc((num_blocks + 1) * sizeof(*block_list)); 553 if (block_list == 0) { 554 critical_error("failed to allocate memory for block_list\n"); 555 } 556 557 if (inode->i_flags & EXT4_EXTENTS_FL) { 558 get_block_list_extents(fd, inode, block_list); 559 } else { 560 /* A directory that requires doubly or triply indirect blocks in huge indeed, 561 * and will almost certainly not exist, especially since make_ext4fs only creates 562 * directories with extents, and the kernel will too, but check to make sure the 563 * directory is not that big and give an error if so. Our limit is 12 direct blocks, 564 * plus block_size/4 singly indirect blocks, which for a filesystem with 4K blocks 565 * is a directory 1036 blocks long, or 4,243,456 bytes long! Assuming an average 566 * filename length of 20 (which I think is generous) thats 20 + 8 bytes overhead 567 * per entry, or 151,552 entries in the directory! 568 */ 569 if (num_blocks > (info.block_size / 4 + EXT4_NDIR_BLOCKS)) { 570 critical_error("Non-extent based directory is too big!\n"); 571 } 572 get_block_list_indirect(fd, inode, block_list); 573 } 574 575 /* Read in all the blocks for this directory */ 576 for (i = 0; i < num_blocks; i++) { 577 read_block(fd, block_list[i], dirbuf + (i * info.block_size)); 578 } 579 580 dirp = (struct ext4_dir_entry_2 *)dirbuf; 581 while (dirp < (struct ext4_dir_entry_2 *)(dirbuf + dirsize)) { 582 count++; 583 leftover_space = (char *)(dirbuf + dirsize) - (char *)dirp; 584 if (((mode == SANITY_CHECK_PASS) || (mode == UPDATE_INODE_NUMS)) && 585 (leftover_space <= 8) && prev_dirp) { 586 /* This is a bug in an older version of make_ext4fs, where it 587 * didn't properly include the rest of the block in rec_len. 588 * Update rec_len on the previous entry to include the rest of 589 * the block and exit the loop. 590 */ 591 if (verbose) { 592 printf("fixing up short rec_len for diretory entry for %s\n", name); 593 } 594 prev_dirp->rec_len += leftover_space; 595 break; 596 } 597 598 if (dirp->inode == 0) { 599 /* This is the last entry in the directory */ 600 break; 601 } 602 603 strncpy(name, dirp->name, dirp->name_len); 604 name[dirp->name_len]='\0'; 605 606 /* Only recurse on pass UPDATE_INODE_NUMS if the high bit is set. 607 * Otherwise, this inode entry has already been updated 608 * and we'll do the wrong thing. Also don't recurse on . or .., 609 * and certainly not on non-directories! 610 */ 611 /* Hrm, looks like filesystems made by fastboot on stingray set the file_type 612 * flag, but the lost+found directory has the type set to Unknown, which 613 * seems to imply I need to read the inode and get it. 614 */ 615 is_dir = is_entry_dir(fd, dirp, mode); 616 if ( is_dir && (strcmp(name, ".") && strcmp(name, "..")) && 617 ((mode == SANITY_CHECK_PASS) || (mode == MARK_INODE_NUMS) || 618 ((mode == UPDATE_INODE_NUMS) && (dirp->inode & 0x80000000))) ) { 619 /* A directory! Recurse! */ 620 read_inode(fd, dirp->inode & 0x7fffffff, &tmp_inode); 621 622 if (!S_ISDIR(tmp_inode.i_mode)) { 623 critical_error("inode %d for name %s does not point to a directory\n", 624 dirp->inode & 0x7fffffff, name); 625 } 626 if (verbose) { 627 printf("inode %d %s use extents\n", dirp->inode & 0x7fffffff, 628 (tmp_inode.i_flags & EXT4_EXTENTS_FL) ? "does" : "does not"); 629 } 630 631 tmp_dirsize = tmp_inode.i_blocks_lo * INODE_BLOCK_SIZE; 632 if (verbose) { 633 printf("dir size = %d bytes\n", tmp_dirsize); 634 } 635 636 tmp_dirbuf = malloc(tmp_dirsize); 637 if (tmp_dirbuf == 0) { 638 critical_error("failed to allocate memory for tmp_dirbuf\n"); 639 } 640 641 recurse_dir(fd, &tmp_inode, tmp_dirbuf, tmp_dirsize, mode); 642 643 free(tmp_dirbuf); 644 } 645 646 if (verbose) { 647 if (is_dir) { 648 printf("Directory %s\n", name); 649 } else { 650 printf("Non-directory %s\n", name); 651 } 652 } 653 654 /* Process entry based on current mode. Either set high bit or change inode number */ 655 if (mode == MARK_INODE_NUMS) { 656 dirp->inode |= 0x80000000; 657 } else if (mode == UPDATE_INODE_NUMS) { 658 if (dirp->inode & 0x80000000) { 659 dirp->inode = compute_new_inum(dirp->inode & 0x7fffffff); 660 } 661 } 662 663 if ((bail_phase == mode) && (bail_loc == 1) && (bail_count == count)) { 664 critical_error("Bailing at phase %d, loc 1 and count %d\n", mode, count); 665 } 666 667 /* Point dirp at the next entry */ 668 prev_dirp = dirp; 669 dirp = (struct ext4_dir_entry_2*)((char *)dirp + dirp->rec_len); 670 } 671 672 /* Write out all the blocks for this directory */ 673 for (i = 0; i < num_blocks; i++) { 674 write_block(fd, block_list[i], dirbuf + (i * info.block_size)); 675 if ((bail_phase == mode) && (bail_loc == 2) && (bail_count <= count)) { 676 critical_error("Bailing at phase %d, loc 2 and count %d\n", mode, count); 677 } 678 } 679 680 free(block_list); 681 682 return 0; 683} 684 685int ext4fixup(char *fsdev) 686{ 687 return ext4fixup_internal(fsdev, 0, 0, 0, 0, 0); 688} 689 690int ext4fixup_internal(char *fsdev, int v_flag, int n_flag, 691 int stop_phase, int stop_loc, int stop_count) 692{ 693 int fd; 694 struct ext4_inode root_inode; 695 unsigned int dirsize; 696 char *dirbuf; 697 698 if (setjmp(setjmp_env)) 699 return EXIT_FAILURE; /* Handle a call to longjmp() */ 700 701 verbose = v_flag; 702 no_write = n_flag; 703 704 bail_phase = stop_phase; 705 bail_loc = stop_loc; 706 bail_count = stop_count; 707 708 fd = open(fsdev, O_RDWR); 709 710 if (fd < 0) 711 critical_error_errno("failed to open filesystem image"); 712 713 read_ext(fd, verbose); 714 715 if (info.feat_incompat & EXT4_FEATURE_INCOMPAT_RECOVER) { 716 critical_error("Filesystem needs recovery first, mount and unmount to do that\n"); 717 } 718 719 /* Clear the low bit which is set while this tool is in progress. 720 * If the tool crashes, it will still be set when we restart. 721 * The low bit is set to make the filesystem unmountable while 722 * it is being fixed up. Also allow 0, which means the old ext2 723 * size is in use. 724 */ 725 if (((aux_info.sb->s_desc_size & ~1) != sizeof(struct ext2_group_desc)) && 726 ((aux_info.sb->s_desc_size & ~1) != 0)) 727 critical_error("error: bg_desc_size != sizeof(struct ext2_group_desc)\n"); 728 729 if ((info.feat_incompat & EXT4_FEATURE_INCOMPAT_FILETYPE) == 0) { 730 critical_error("Expected filesystem to have filetype flag set\n"); 731 } 732 733#if 0 // If we have to fix the directory rec_len issue, we can't use this check 734 /* Check to see if the inodes/group is copacetic */ 735 if (info.inodes_per_blockgroup % (info.block_size/info.inode_size) == 0) { 736 /* This filesystem has either already been updated, or was 737 * made correctly. 738 */ 739 if (verbose) { 740 printf("%s: filesystem correct, no work to do\n", me); 741 } 742 exit(0); 743 } 744#endif 745 746 /* Compute what the new value of inodes_per_blockgroup will be when we're done */ 747 new_inodes_per_group=EXT4_ALIGN(info.inodes_per_group,(info.block_size/info.inode_size)); 748 749 read_inode(fd, EXT4_ROOT_INO, &root_inode); 750 751 if (!S_ISDIR(root_inode.i_mode)) { 752 critical_error("root inode %d does not point to a directory\n", EXT4_ROOT_INO); 753 } 754 if (verbose) { 755 printf("inode %d %s use extents\n", EXT4_ROOT_INO, 756 (root_inode.i_flags & EXT4_EXTENTS_FL) ? "does" : "does not"); 757 } 758 759 dirsize = root_inode.i_blocks_lo * INODE_BLOCK_SIZE; 760 if (verbose) { 761 printf("root dir size = %d bytes\n", dirsize); 762 } 763 764 dirbuf = malloc(dirsize); 765 if (dirbuf == 0) { 766 critical_error("failed to allocate memory for dirbuf\n"); 767 } 768 769 /* Perform a sanity check pass first, try to catch any errors that will occur 770 * before we actually change anything, so we don't leave a filesystem in a 771 * corrupted, unrecoverable state. Set no_write, make it quiet, and do a recurse 772 * pass and a update_superblock pass. Set flags back to requested state when done. 773 * Only perform sanity check if the state is unset. If the state is _NOT_ unset, 774 * then the tool has already been run and interrupted, and it presumably ran and 775 * passed sanity checked before it got interrupted. It is _NOT_ safe to run sanity 776 * check if state is unset because it assumes inodes are to be computed using the 777 * old inodes/group, but some inode numbers may be updated to the new number. 778 */ 779 if (get_fs_fixup_state(fd) == STATE_UNSET) { 780 verbose = 0; 781 no_write = 1; 782 recurse_dir(fd, &root_inode, dirbuf, dirsize, SANITY_CHECK_PASS); 783 update_superblocks_and_bg_desc(fd, STATE_UNSET); 784 verbose = v_flag; 785 no_write = n_flag; 786 787 set_fs_fixup_state(fd, STATE_MARKING_INUMS); 788 } 789 790 if (get_fs_fixup_state(fd) == STATE_MARKING_INUMS) { 791 count = 0; /* Reset debugging counter */ 792 if (!recurse_dir(fd, &root_inode, dirbuf, dirsize, MARK_INODE_NUMS)) { 793 set_fs_fixup_state(fd, STATE_UPDATING_INUMS); 794 } 795 } 796 797 if (get_fs_fixup_state(fd) == STATE_UPDATING_INUMS) { 798 count = 0; /* Reset debugging counter */ 799 if (!recurse_dir(fd, &root_inode, dirbuf, dirsize, UPDATE_INODE_NUMS)) { 800 set_fs_fixup_state(fd, STATE_UPDATING_SB); 801 } 802 } 803 804 if (get_fs_fixup_state(fd) == STATE_UPDATING_SB) { 805 /* set the new inodes/blockgroup number, 806 * and sets the state back to 0. 807 */ 808 if (!update_superblocks_and_bg_desc(fd, STATE_UPDATING_SB)) { 809 set_fs_fixup_state(fd, STATE_UNSET); 810 } 811 } 812 813 close(fd); 814 free(dirbuf); 815 816 return 0; 817} 818