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 "output_file.h" 20 #include "backed_block.h" 21 #include "allocate.h" 22 #include "ext4fixup.h" 23 24 #include <sys/types.h> 25 #include <sys/stat.h> 26 #include <sys/types.h> 27 #include <sys/mman.h> 28 #include <fcntl.h> 29 #include <unistd.h> 30 31 #if defined(__APPLE__) && defined(__MACH__) 32 #define lseek64 lseek 33 #define off64_t off_t 34 #endif 35 36 /* The inode block count for a file/directory is in units of 512 byte blocks, 37 * _NOT_ the filesystem block size! 38 */ 39 #define INODE_BLOCK_SIZE 512 40 41 #define MAX_EXT4_BLOCK_SIZE 4096 42 43 /* The two modes the recurse_dir() can be in */ 44 #define SANITY_CHECK_PASS 1 45 #define MARK_INODE_NUMS 2 46 #define UPDATE_INODE_NUMS 3 47 48 /* Magic numbers to indicate what state the update process is in */ 49 #define MAGIC_STATE_MARKING_INUMS 0x7000151515565512ll 50 #define MAGIC_STATE_UPDATING_INUMS 0x6121131211735123ll 51 #define MAGIC_STATE_UPDATING_SB 0x15e1715151558477ll 52 53 /* Internal state variables corresponding to the magic numbers */ 54 #define STATE_UNSET 0 55 #define STATE_MARKING_INUMS 1 56 #define STATE_UPDATING_INUMS 2 57 #define STATE_UPDATING_SB 3 58 59 /* Used for automated testing of this programs ability to stop and be restarted wthout error */ 60 static int bail_phase = 0; 61 static int bail_loc = 0; 62 static int bail_count = 0; 63 static int count = 0; 64 65 /* global flags */ 66 static int verbose = 0; 67 static int no_write = 0; 68 69 static int new_inodes_per_group = 0; 70 71 static int no_write_fixup_state = 0; 72 73 static int compute_new_inum(unsigned int old_inum) 74 { 75 unsigned int group, offset; 76 77 group = (old_inum - 1) / info.inodes_per_group; 78 offset = (old_inum -1) % info.inodes_per_group; 79 80 return (group * new_inodes_per_group) + offset + 1; 81 } 82 83 /* Function to read the primary superblock */ 84 static void read_sb(int fd, struct ext4_super_block *sb) 85 { 86 off64_t ret; 87 88 ret = lseek64(fd, 1024, SEEK_SET); 89 if (ret < 0) 90 critical_error_errno("failed to seek to superblock"); 91 92 ret = read(fd, sb, sizeof(*sb)); 93 if (ret < 0) 94 critical_error_errno("failed to read superblock"); 95 if (ret != sizeof(*sb)) 96 critical_error("failed to read all of superblock"); 97 } 98 99 /* Function to write a primary or backup superblock at a given offset */ 100 static void write_sb(int fd, unsigned long long offset, struct ext4_super_block *sb) 101 { 102 off64_t ret; 103 104 if (no_write) { 105 return; 106 } 107 108 ret = lseek64(fd, offset, SEEK_SET); 109 if (ret < 0) 110 critical_error_errno("failed to seek to superblock"); 111 112 ret = write(fd, sb, sizeof(*sb)); 113 if (ret < 0) 114 critical_error_errno("failed to write superblock"); 115 if (ret != sizeof(*sb)) 116 critical_error("failed to write all of superblock"); 117 } 118 119 static int get_fs_fixup_state(int fd) 120 { 121 unsigned long long magic; 122 int ret, len; 123 124 if (no_write) { 125 return no_write_fixup_state; 126 } 127 128 lseek64(fd, 0, SEEK_SET); 129 len = read(fd, &magic, sizeof(magic)); 130 if (len != sizeof(magic)) { 131 critical_error("cannot read fixup_state\n"); 132 } 133 134 switch (magic) { 135 case MAGIC_STATE_MARKING_INUMS: 136 ret = STATE_MARKING_INUMS; 137 break; 138 case MAGIC_STATE_UPDATING_INUMS: 139 ret = STATE_UPDATING_INUMS; 140 break; 141 case MAGIC_STATE_UPDATING_SB: 142 ret = STATE_UPDATING_SB; 143 break; 144 default: 145 ret = STATE_UNSET; 146 } 147 return ret; 148 } 149 150 static int set_fs_fixup_state(int fd, int state) 151 { 152 unsigned long long magic; 153 struct ext4_super_block sb; 154 int len; 155 156 if (no_write) { 157 no_write_fixup_state = state; 158 return 0; 159 } 160 161 switch (state) { 162 case STATE_MARKING_INUMS: 163 magic = MAGIC_STATE_MARKING_INUMS; 164 break; 165 case STATE_UPDATING_INUMS: 166 magic = MAGIC_STATE_UPDATING_INUMS; 167 break; 168 case STATE_UPDATING_SB: 169 magic = MAGIC_STATE_UPDATING_SB; 170 break; 171 case STATE_UNSET: 172 default: 173 magic = 0ll; 174 break; 175 } 176 177 lseek64(fd, 0, SEEK_SET); 178 len = write(fd, &magic, sizeof(magic)); 179 if (len != sizeof(magic)) { 180 critical_error("cannot write fixup_state\n"); 181 } 182 183 read_sb(fd, &sb); 184 if (magic) { 185 /* If we are in the process of updating the filesystem, make it unmountable */ 186 sb.s_desc_size |= 1; 187 } else { 188 /* we are done, so make the filesystem mountable again */ 189 sb.s_desc_size &= ~1; 190 } 191 write_sb(fd, 1024, &sb); 192 193 return 0; 194 } 195 196 static int read_ext(int fd) 197 { 198 off64_t ret; 199 struct ext4_super_block sb; 200 unsigned int i; 201 202 read_sb(fd, &sb); 203 204 ext4_parse_sb(&sb); 205 206 if (info.feat_incompat & EXT4_FEATURE_INCOMPAT_RECOVER) { 207 critical_error("Filesystem needs recovery first, mount and unmount to do that\n"); 208 } 209 210 /* Clear the low bit which is set while this tool is in progress. 211 * If the tool crashes, it will still be set when we restart. 212 * The low bit is set to make the filesystem unmountable while 213 * it is being fixed up. Also allow 0, which means the old ext2 214 * size is in use. 215 */ 216 if (((sb.s_desc_size & ~1) != sizeof(struct ext2_group_desc)) && 217 ((sb.s_desc_size & ~1) != 0)) 218 critical_error("error: bg_desc_size != sizeof(struct ext2_group_desc)\n"); 219 220 ret = lseek64(fd, info.len, SEEK_SET); 221 if (ret < 0) 222 critical_error_errno("failed to seek to end of input image"); 223 224 ret = lseek64(fd, info.block_size * (aux_info.first_data_block + 1), SEEK_SET); 225 if (ret < 0) 226 critical_error_errno("failed to seek to block group descriptors"); 227 228 ret = read(fd, aux_info.bg_desc, info.block_size * aux_info.bg_desc_blocks); 229 if (ret < 0) 230 critical_error_errno("failed to read block group descriptors"); 231 if (ret != (int)info.block_size * (int)aux_info.bg_desc_blocks) 232 critical_error("failed to read all of block group descriptors"); 233 234 if (verbose) { 235 printf("Found filesystem with parameters:\n"); 236 printf(" Size: %llu\n", info.len); 237 printf(" Block size: %d\n", info.block_size); 238 printf(" Blocks per group: %d\n", info.blocks_per_group); 239 printf(" Inodes per group: %d\n", info.inodes_per_group); 240 printf(" Inode size: %d\n", info.inode_size); 241 printf(" Label: %s\n", info.label); 242 printf(" Blocks: %llu\n", aux_info.len_blocks); 243 printf(" Block groups: %d\n", aux_info.groups); 244 printf(" Reserved block group size: %d\n", info.bg_desc_reserve_blocks); 245 printf(" Used %d/%d inodes and %d/%d blocks\n", 246 aux_info.sb->s_inodes_count - aux_info.sb->s_free_inodes_count, 247 aux_info.sb->s_inodes_count, 248 aux_info.sb->s_blocks_count_lo - aux_info.sb->s_free_blocks_count_lo, 249 aux_info.sb->s_blocks_count_lo); 250 } 251 252 return 0; 253 } 254 255 static int read_inode(int fd, unsigned int inum, struct ext4_inode *inode) 256 { 257 unsigned int bg_num, bg_offset; 258 off64_t inode_offset; 259 int len; 260 261 bg_num = (inum-1) / info.inodes_per_group; 262 bg_offset = (inum-1) % info.inodes_per_group; 263 264 inode_offset = ((unsigned long long)aux_info.bg_desc[bg_num].bg_inode_table * info.block_size) + 265 (bg_offset * info.inode_size); 266 267 if (lseek64(fd, inode_offset, SEEK_SET) < 0) { 268 critical_error_errno("failed to seek to inode %d\n", inum); 269 } 270 271 len=read(fd, inode, sizeof(*inode)); 272 if (len != sizeof(*inode)) { 273 critical_error_errno("failed to read inode %d\n", inum); 274 } 275 276 return 0; 277 } 278 279 static int read_block(int fd, unsigned long long block_num, void *block) 280 { 281 off64_t off; 282 unsigned int len; 283 284 off = block_num * info.block_size; 285 286 if (lseek64(fd, off, SEEK_SET) , 0) { 287 critical_error_errno("failed to seek to block %lld\n", block_num); 288 } 289 290 len=read(fd, block, info.block_size); 291 if (len != info.block_size) { 292 critical_error_errno("failed to read block %lld\n", block_num); 293 } 294 295 return 0; 296 } 297 298 static int write_block(int fd, unsigned long long block_num, void *block) 299 { 300 off64_t off; 301 unsigned int len; 302 303 if (no_write) { 304 return 0; 305 } 306 307 off = block_num * info.block_size; 308 309 if (lseek64(fd, off, SEEK_SET) < 0) { 310 critical_error_errno("failed to seek to block %lld\n", block_num); 311 } 312 313 len=write(fd, block, info.block_size); 314 if (len != info.block_size) { 315 critical_error_errno("failed to write block %lld\n", block_num); 316 } 317 318 return 0; 319 } 320 321 static int bitmap_get_bit(u8 *bitmap, u32 bit) 322 { 323 if (bitmap[bit / 8] & (1 << (bit % 8))) 324 return 1; 325 326 return 0; 327 } 328 329 static void bitmap_clear_bit(u8 *bitmap, u32 bit) 330 { 331 bitmap[bit / 8] &= ~(1 << (bit % 8)); 332 333 return; 334 } 335 336 static void check_inode_bitmap(int fd, unsigned int bg_num) 337 { 338 unsigned int inode_bitmap_block_num; 339 unsigned char block[MAX_EXT4_BLOCK_SIZE]; 340 int i, bitmap_updated = 0; 341 342 /* Using the bg_num, aux_info.bg_desc[], info.inodes_per_group and 343 * new_inodes_per_group, retrieve the inode bitmap, and make sure 344 * the bits between the old and new size are clear 345 */ 346 inode_bitmap_block_num = aux_info.bg_desc[bg_num].bg_inode_bitmap; 347 348 read_block(fd, inode_bitmap_block_num, block); 349 350 for (i = info.inodes_per_group; i < new_inodes_per_group; i++) { 351 if (bitmap_get_bit(block, i)) { 352 bitmap_clear_bit(block, i); 353 bitmap_updated = 1; 354 } 355 } 356 357 if (bitmap_updated) { 358 if (verbose) { 359 printf("Warning: updated inode bitmap for block group %d\n", bg_num); 360 } 361 write_block(fd, inode_bitmap_block_num, block); 362 } 363 364 return; 365 } 366 367 /* Update the superblock and bgdesc of the specified block group */ 368 static int update_superblocks_and_bg_desc(int fd, int state) 369 { 370 off64_t ret; 371 struct ext4_super_block sb; 372 unsigned int num_block_groups, total_new_inodes; 373 unsigned int i; 374 375 376 read_sb(fd, &sb); 377 378 /* Compute how many more inodes are now available */ 379 num_block_groups = DIV_ROUND_UP(aux_info.len_blocks, info.blocks_per_group); 380 total_new_inodes = num_block_groups * (new_inodes_per_group - sb.s_inodes_per_group); 381 382 if (verbose) { 383 printf("created %d additional inodes\n", total_new_inodes); 384 } 385 386 /* Update the free inodes count in each block group descriptor */ 387 for (i = 0; i < num_block_groups; i++) { 388 if (state == STATE_UPDATING_SB) { 389 aux_info.bg_desc[i].bg_free_inodes_count += (new_inodes_per_group - sb.s_inodes_per_group); 390 } 391 check_inode_bitmap(fd, i); 392 } 393 394 /* First some sanity checks */ 395 if ((sb.s_inodes_count + total_new_inodes) != (new_inodes_per_group * num_block_groups)) { 396 critical_error("Failed sanity check on new inode count\n"); 397 } 398 if (new_inodes_per_group % (info.block_size/info.inode_size)) { 399 critical_error("Failed sanity check on new inode per group alignment\n"); 400 } 401 402 /* Update the free inodes count in the superblock */ 403 sb.s_inodes_count += total_new_inodes; 404 sb.s_free_inodes_count += total_new_inodes; 405 sb.s_inodes_per_group = new_inodes_per_group; 406 407 for (i = 0; i < aux_info.groups; i++) { 408 if (ext4_bg_has_super_block(i)) { 409 unsigned int sb_offset; 410 411 if (i == 0) { 412 /* The first superblock is offset by 1K to leave room for boot sectors */ 413 sb_offset = 1024; 414 } else { 415 sb_offset = 0; 416 } 417 418 sb.s_block_group_nr = i; 419 /* Don't write out the backup superblocks with the bit set in the s_desc_size 420 * which prevents the filesystem from mounting. The bit for the primary 421 * superblock will be cleared on the final call to set_fs_fixup_state() */ 422 if (i != 0) { 423 sb.s_desc_size &= ~1; 424 } 425 426 write_sb(fd, (unsigned long long)i * info.blocks_per_group * info.block_size + sb_offset, &sb); 427 428 ret = lseek64(fd, ((unsigned long long)i * info.blocks_per_group * info.block_size) + 429 (info.block_size * (aux_info.first_data_block + 1)), SEEK_SET); 430 if (ret < 0) 431 critical_error_errno("failed to seek to block group descriptors"); 432 433 if (!no_write) { 434 ret = write(fd, aux_info.bg_desc, info.block_size * aux_info.bg_desc_blocks); 435 if (ret < 0) 436 critical_error_errno("failed to write block group descriptors"); 437 if (ret != (int)info.block_size * (int)aux_info.bg_desc_blocks) 438 critical_error("failed to write all of block group descriptors"); 439 } 440 } 441 if ((bail_phase == 4) && ((unsigned int)bail_count == i)) { 442 critical_error("bailing at phase 4\n"); 443 } 444 } 445 446 return 0; 447 } 448 449 450 static int get_direct_blocks(struct ext4_inode *inode, unsigned long long *block_list, 451 unsigned int *count) 452 { 453 unsigned int i = 0; 454 unsigned int ret = 0; 455 unsigned int sectors_per_block; 456 457 sectors_per_block = info.block_size / INODE_BLOCK_SIZE; 458 while ((i < (inode->i_blocks_lo / sectors_per_block)) && (i < EXT4_NDIR_BLOCKS)) { 459 block_list[i] = inode->i_block[i]; 460 i++; 461 } 462 463 *count += i; 464 465 if ((inode->i_blocks_lo / sectors_per_block) > EXT4_NDIR_BLOCKS) { 466 ret = 1; 467 } 468 469 return ret; 470 } 471 472 static int get_indirect_blocks(int fd, struct ext4_inode *inode, 473 unsigned long long *block_list, unsigned int *count) 474 { 475 unsigned int i; 476 unsigned int *indirect_block; 477 unsigned int sectors_per_block; 478 479 sectors_per_block = info.block_size / INODE_BLOCK_SIZE; 480 481 indirect_block = (unsigned int *)malloc(info.block_size); 482 if (indirect_block == 0) { 483 critical_error("failed to allocate memory for indirect_block\n"); 484 } 485 486 read_block(fd, inode->i_block[EXT4_NDIR_BLOCKS], indirect_block); 487 488 for(i = 0; i < (inode->i_blocks_lo / sectors_per_block - EXT4_NDIR_BLOCKS); i++) { 489 block_list[EXT4_NDIR_BLOCKS+i] = indirect_block[i]; 490 } 491 492 *count += i; 493 494 free(indirect_block); 495 496 return 0; 497 } 498 499 static int get_block_list_indirect(int fd, struct ext4_inode *inode, unsigned long long *block_list) 500 { 501 unsigned int count=0; 502 503 if (get_direct_blocks(inode, block_list, &count)) { 504 get_indirect_blocks(fd, inode, block_list, &count); 505 } 506 507 return count; 508 } 509 510 static int get_extent_ents(int fd, struct ext4_extent_header *ext_hdr, unsigned long long *block_list) 511 { 512 int i, j; 513 struct ext4_extent *extent; 514 off64_t fs_block_num; 515 516 if (ext_hdr->eh_depth != 0) { 517 critical_error("get_extent_ents called with eh_depth != 0\n"); 518 } 519 520 /* The extent entries immediately follow the header, so add 1 to the pointer 521 * and cast it to an extent pointer. 522 */ 523 extent = (struct ext4_extent *)(ext_hdr + 1); 524 525 for (i = 0; i < ext_hdr->eh_entries; i++) { 526 fs_block_num = ((off64_t)extent->ee_start_hi << 32) | extent->ee_start_lo; 527 for (j = 0; j < extent->ee_len; j++) { 528 block_list[extent->ee_block+j] = fs_block_num+j; 529 } 530 extent++; 531 } 532 533 return 0; 534 } 535 536 static int get_extent_idx(int fd, struct ext4_extent_header *ext_hdr, unsigned long long *block_list) 537 { 538 int i; 539 struct ext4_extent_idx *extent_idx; 540 struct ext4_extent_header *tmp_ext_hdr; 541 off64_t fs_block_num; 542 unsigned char block[MAX_EXT4_BLOCK_SIZE]; 543 544 /* Sanity check */ 545 if (ext_hdr->eh_depth == 0) { 546 critical_error("get_extent_idx called with eh_depth == 0\n"); 547 } 548 549 /* The extent entries immediately follow the header, so add 1 to the pointer 550 * and cast it to an extent pointer. 551 */ 552 extent_idx = (struct ext4_extent_idx *)(ext_hdr + 1); 553 554 for (i = 0; i < ext_hdr->eh_entries; i++) { 555 fs_block_num = ((off64_t)extent_idx->ei_leaf_hi << 32) | extent_idx->ei_leaf_lo; 556 read_block(fd, fs_block_num, block); 557 tmp_ext_hdr = (struct ext4_extent_header *)block; 558 559 if (tmp_ext_hdr->eh_depth == 0) { 560 get_extent_ents(fd, tmp_ext_hdr, block_list); /* leaf node, fill in block_list */ 561 } else { 562 get_extent_idx(fd, tmp_ext_hdr, block_list); /* recurse down the tree */ 563 } 564 } 565 566 return 0; 567 } 568 569 static int get_block_list_extents(int fd, struct ext4_inode *inode, unsigned long long *block_list) 570 { 571 struct ext4_extent_header *extent_hdr; 572 573 extent_hdr = (struct ext4_extent_header *)inode->i_block; 574 575 if (extent_hdr->eh_magic != EXT4_EXT_MAGIC) { 576 critical_error("extent header has unexpected magic value 0x%4.4x\n", 577 extent_hdr->eh_magic); 578 } 579 580 if (extent_hdr->eh_depth == 0) { 581 get_extent_ents(fd, (struct ext4_extent_header *)inode->i_block, block_list); 582 return 0; 583 } 584 585 get_extent_idx(fd, (struct ext4_extent_header *)inode->i_block, block_list); 586 587 return 0; 588 } 589 590 static int is_entry_dir(int fd, struct ext4_dir_entry_2 *dirp, int pass) 591 { 592 struct ext4_inode inode; 593 int ret = 0; 594 595 if (dirp->file_type == EXT4_FT_DIR) { 596 ret = 1; 597 } else if (dirp->file_type == EXT4_FT_UNKNOWN) { 598 /* Somebody was too lazy to fill in the dir entry, 599 * so we have to go fetch it from the inode. Grrr. 600 */ 601 /* if UPDATE_INODE_NUMS pass and the inode high bit is not 602 * set return false so we don't recurse down the tree that is 603 * already updated. Otherwise, fetch inode, and return answer. 604 */ 605 if ((pass == UPDATE_INODE_NUMS) && !(dirp->inode & 0x80000000)) { 606 ret = 0; 607 } else { 608 read_inode(fd, (dirp->inode & 0x7fffffff), &inode); 609 if (S_ISDIR(inode.i_mode)) { 610 ret = 1; 611 } 612 } 613 } 614 615 return ret; 616 } 617 618 static int recurse_dir(int fd, struct ext4_inode *inode, char *dirbuf, int dirsize, int mode) 619 { 620 unsigned long long *block_list; 621 unsigned int num_blocks; 622 struct ext4_dir_entry_2 *dirp, *prev_dirp = 0; 623 char name[256]; 624 unsigned int i, leftover_space, is_dir; 625 struct ext4_inode tmp_inode; 626 int tmp_dirsize; 627 char *tmp_dirbuf; 628 629 switch (mode) { 630 case SANITY_CHECK_PASS: 631 case MARK_INODE_NUMS: 632 case UPDATE_INODE_NUMS: 633 break; 634 default: 635 critical_error("recurse_dir() called witn unknown mode!\n"); 636 } 637 638 if (dirsize % info.block_size) { 639 critical_error("dirsize %d not a multiple of block_size %d. This is unexpected!\n", 640 dirsize, info.block_size); 641 } 642 643 num_blocks = dirsize / info.block_size; 644 645 block_list = malloc((num_blocks + 1) * sizeof(*block_list)); 646 if (block_list == 0) { 647 critical_error("failed to allocate memory for block_list\n"); 648 } 649 650 if (inode->i_flags & EXT4_EXTENTS_FL) { 651 get_block_list_extents(fd, inode, block_list); 652 } else { 653 /* A directory that requires doubly or triply indirect blocks in huge indeed, 654 * and will almost certainly not exist, especially since make_ext4fs only creates 655 * directories with extents, and the kernel will too, but check to make sure the 656 * directory is not that big and give an error if so. Our limit is 12 direct blocks, 657 * plus block_size/4 singly indirect blocks, which for a filesystem with 4K blocks 658 * is a directory 1036 blocks long, or 4,243,456 bytes long! Assuming an average 659 * filename length of 20 (which I think is generous) thats 20 + 8 bytes overhead 660 * per entry, or 151,552 entries in the directory! 661 */ 662 if (num_blocks > (info.block_size / 4 + EXT4_NDIR_BLOCKS)) { 663 critical_error("Non-extent based directory is too big!\n"); 664 } 665 get_block_list_indirect(fd, inode, block_list); 666 } 667 668 /* Read in all the blocks for this directory */ 669 for (i = 0; i < num_blocks; i++) { 670 read_block(fd, block_list[i], dirbuf + (i * info.block_size)); 671 } 672 673 dirp = (struct ext4_dir_entry_2 *)dirbuf; 674 while (dirp < (struct ext4_dir_entry_2 *)(dirbuf + dirsize)) { 675 count++; 676 leftover_space = (char *)(dirbuf + dirsize) - (char *)dirp; 677 if (((mode == SANITY_CHECK_PASS) || (mode == UPDATE_INODE_NUMS)) && 678 (leftover_space <= 8) && prev_dirp) { 679 /* This is a bug in an older version of make_ext4fs, where it 680 * didn't properly include the rest of the block in rec_len. 681 * Update rec_len on the previous entry to include the rest of 682 * the block and exit the loop. 683 */ 684 if (verbose) { 685 printf("fixing up short rec_len for diretory entry for %s\n", name); 686 } 687 prev_dirp->rec_len += leftover_space; 688 break; 689 } 690 691 if (dirp->inode == 0) { 692 /* This is the last entry in the directory */ 693 break; 694 } 695 696 strncpy(name, dirp->name, dirp->name_len); 697 name[dirp->name_len]='\0'; 698 699 /* Only recurse on pass UPDATE_INODE_NUMS if the high bit is set. 700 * Otherwise, this inode entry has already been updated 701 * and we'll do the wrong thing. Also don't recurse on . or .., 702 * and certainly not on non-directories! 703 */ 704 /* Hrm, looks like filesystems made by fastboot on stingray set the file_type 705 * flag, but the lost+found directory has the type set to Unknown, which 706 * seems to imply I need to read the inode and get it. 707 */ 708 is_dir = is_entry_dir(fd, dirp, mode); 709 if ( is_dir && (strcmp(name, ".") && strcmp(name, "..")) && 710 ((mode == SANITY_CHECK_PASS) || (mode == MARK_INODE_NUMS) || 711 ((mode == UPDATE_INODE_NUMS) && (dirp->inode & 0x80000000))) ) { 712 /* A directory! Recurse! */ 713 read_inode(fd, dirp->inode & 0x7fffffff, &tmp_inode); 714 715 if (!S_ISDIR(tmp_inode.i_mode)) { 716 critical_error("inode %d for name %s does not point to a directory\n", 717 dirp->inode & 0x7fffffff, name); 718 } 719 if (verbose) { 720 printf("inode %d %s use extents\n", dirp->inode & 0x7fffffff, 721 (tmp_inode.i_flags & EXT4_EXTENTS_FL) ? "does" : "does not"); 722 } 723 724 tmp_dirsize = tmp_inode.i_blocks_lo * INODE_BLOCK_SIZE; 725 if (verbose) { 726 printf("dir size = %d bytes\n", tmp_dirsize); 727 } 728 729 tmp_dirbuf = malloc(tmp_dirsize); 730 if (tmp_dirbuf == 0) { 731 critical_error("failed to allocate memory for tmp_dirbuf\n"); 732 } 733 734 recurse_dir(fd, &tmp_inode, tmp_dirbuf, tmp_dirsize, mode); 735 736 free(tmp_dirbuf); 737 } 738 739 if (verbose) { 740 if (is_dir) { 741 printf("Directory %s\n", name); 742 } else { 743 printf("Non-directory %s\n", name); 744 } 745 } 746 747 /* Process entry based on current mode. Either set high bit or change inode number */ 748 if (mode == MARK_INODE_NUMS) { 749 dirp->inode |= 0x80000000; 750 } else if (mode == UPDATE_INODE_NUMS) { 751 if (dirp->inode & 0x80000000) { 752 dirp->inode = compute_new_inum(dirp->inode & 0x7fffffff); 753 } 754 } 755 756 if ((bail_phase == mode) && (bail_loc == 1) && (bail_count == count)) { 757 critical_error("Bailing at phase %d, loc 1 and count %d\n", mode, count); 758 } 759 760 /* Point dirp at the next entry */ 761 prev_dirp = dirp; 762 dirp = (struct ext4_dir_entry_2*)((char *)dirp + dirp->rec_len); 763 } 764 765 /* Write out all the blocks for this directory */ 766 for (i = 0; i < num_blocks; i++) { 767 write_block(fd, block_list[i], dirbuf + (i * info.block_size)); 768 if ((bail_phase == mode) && (bail_loc == 2) && (bail_count <= count)) { 769 critical_error("Bailing at phase %d, loc 2 and count %d\n", mode, count); 770 } 771 } 772 773 free(block_list); 774 775 return 0; 776 } 777 778 int ext4fixup(char *fsdev) 779 { 780 return ext4fixup_internal(fsdev, 0, 0, 0, 0, 0); 781 } 782 783 int ext4fixup_internal(char *fsdev, int v_flag, int n_flag, 784 int stop_phase, int stop_loc, int stop_count) 785 { 786 int fd; 787 struct ext4_inode root_inode; 788 unsigned int dirsize; 789 char *dirbuf; 790 791 if (setjmp(setjmp_env)) 792 return EXIT_FAILURE; /* Handle a call to longjmp() */ 793 794 verbose = v_flag; 795 no_write = n_flag; 796 797 bail_phase = stop_phase; 798 bail_loc = stop_loc; 799 bail_count = stop_count; 800 801 fd = open(fsdev, O_RDWR); 802 803 if (fd < 0) 804 critical_error_errno("failed to open filesystem image"); 805 806 read_ext(fd); 807 808 if ((info.feat_incompat & EXT4_FEATURE_INCOMPAT_FILETYPE) == 0) { 809 critical_error("Expected filesystem to have filetype flag set\n"); 810 } 811 812 #if 0 // If we have to fix the directory rec_len issue, we can't use this check 813 /* Check to see if the inodes/group is copacetic */ 814 if (info.inodes_per_blockgroup % (info.block_size/info.inode_size) == 0) { 815 /* This filesystem has either already been updated, or was 816 * made correctly. 817 */ 818 if (verbose) { 819 printf("%s: filesystem correct, no work to do\n", me); 820 } 821 exit(0); 822 } 823 #endif 824 825 /* Compute what the new value of inodes_per_blockgroup will be when we're done */ 826 new_inodes_per_group=ALIGN(info.inodes_per_group,(info.block_size/info.inode_size)); 827 828 read_inode(fd, EXT4_ROOT_INO, &root_inode); 829 830 if (!S_ISDIR(root_inode.i_mode)) { 831 critical_error("root inode %d does not point to a directory\n", EXT4_ROOT_INO); 832 } 833 if (verbose) { 834 printf("inode %d %s use extents\n", EXT4_ROOT_INO, 835 (root_inode.i_flags & EXT4_EXTENTS_FL) ? "does" : "does not"); 836 } 837 838 dirsize = root_inode.i_blocks_lo * INODE_BLOCK_SIZE; 839 if (verbose) { 840 printf("root dir size = %d bytes\n", dirsize); 841 } 842 843 dirbuf = malloc(dirsize); 844 if (dirbuf == 0) { 845 critical_error("failed to allocate memory for dirbuf\n"); 846 } 847 848 /* Perform a sanity check pass first, try to catch any errors that will occur 849 * before we actually change anything, so we don't leave a filesystem in a 850 * corrupted, unrecoverable state. Set no_write, make it quiet, and do a recurse 851 * pass and a update_superblock pass. Set flags back to requested state when done. 852 * Only perform sanity check if the state is unset. If the state is _NOT_ unset, 853 * then the tool has already been run and interrupted, and it presumably ran and 854 * passed sanity checked before it got interrupted. It is _NOT_ safe to run sanity 855 * check if state is unset because it assumes inodes are to be computed using the 856 * old inodes/group, but some inode numbers may be updated to the new number. 857 */ 858 if (get_fs_fixup_state(fd) == STATE_UNSET) { 859 verbose = 0; 860 no_write = 1; 861 recurse_dir(fd, &root_inode, dirbuf, dirsize, SANITY_CHECK_PASS); 862 update_superblocks_and_bg_desc(fd, STATE_UNSET); 863 verbose = v_flag; 864 no_write = n_flag; 865 866 set_fs_fixup_state(fd, STATE_MARKING_INUMS); 867 } 868 869 if (get_fs_fixup_state(fd) == STATE_MARKING_INUMS) { 870 count = 0; /* Reset debugging counter */ 871 if (!recurse_dir(fd, &root_inode, dirbuf, dirsize, MARK_INODE_NUMS)) { 872 set_fs_fixup_state(fd, STATE_UPDATING_INUMS); 873 } 874 } 875 876 if (get_fs_fixup_state(fd) == STATE_UPDATING_INUMS) { 877 count = 0; /* Reset debugging counter */ 878 if (!recurse_dir(fd, &root_inode, dirbuf, dirsize, UPDATE_INODE_NUMS)) { 879 set_fs_fixup_state(fd, STATE_UPDATING_SB); 880 } 881 } 882 883 if (get_fs_fixup_state(fd) == STATE_UPDATING_SB) { 884 /* set the new inodes/blockgroup number, 885 * and sets the state back to 0. 886 */ 887 if (!update_superblocks_and_bg_desc(fd, STATE_UPDATING_SB)) { 888 set_fs_fixup_state(fd, STATE_UNSET); 889 } 890 } 891 892 close(fd); 893 894 return 0; 895 } 896
