1 /* 2 * (C) Copyright 2011 - 2012 Samsung Electronics 3 * EXT4 filesystem implementation in Uboot by 4 * Uma Shankar <uma.shankar@samsung.com> 5 * Manjunatha C Achar <a.manjunatha@samsung.com> 6 * 7 * ext4ls and ext4load : Based on ext2 ls load support in Uboot. 8 * 9 * (C) Copyright 2004 10 * esd gmbh <www.esd-electronics.com> 11 * Reinhard Arlt <reinhard.arlt@esd-electronics.com> 12 * 13 * based on code from grub2 fs/ext2.c and fs/fshelp.c by 14 * GRUB -- GRand Unified Bootloader 15 * Copyright (C) 2003, 2004 Free Software Foundation, Inc. 16 * 17 * ext4write : Based on generic ext4 protocol. 18 * 19 * SPDX-License-Identifier: GPL-2.0+ 20 */ 21 22 #include <common.h> 23 #include <ext_common.h> 24 #include <ext4fs.h> 25 #include <inttypes.h> 26 #include <malloc.h> 27 #include <memalign.h> 28 #include <stddef.h> 29 #include <linux/stat.h> 30 #include <linux/time.h> 31 #include <asm/byteorder.h> 32 #include "ext4_common.h" 33 34 struct ext2_data *ext4fs_root; 35 struct ext2fs_node *ext4fs_file; 36 uint32_t *ext4fs_indir1_block; 37 int ext4fs_indir1_size; 38 int ext4fs_indir1_blkno = -1; 39 uint32_t *ext4fs_indir2_block; 40 int ext4fs_indir2_size; 41 int ext4fs_indir2_blkno = -1; 42 43 uint32_t *ext4fs_indir3_block; 44 int ext4fs_indir3_size; 45 int ext4fs_indir3_blkno = -1; 46 struct ext2_inode *g_parent_inode; 47 static int symlinknest; 48 49 #if defined(CONFIG_EXT4_WRITE) 50 uint32_t ext4fs_div_roundup(uint32_t size, uint32_t n) 51 { 52 uint32_t res = size / n; 53 if (res * n != size) 54 res++; 55 56 return res; 57 } 58 59 void put_ext4(uint64_t off, void *buf, uint32_t size) 60 { 61 uint64_t startblock; 62 uint64_t remainder; 63 unsigned char *temp_ptr = NULL; 64 struct ext_filesystem *fs = get_fs(); 65 int log2blksz = fs->dev_desc->log2blksz; 66 ALLOC_CACHE_ALIGN_BUFFER(unsigned char, sec_buf, fs->dev_desc->blksz); 67 68 startblock = off >> log2blksz; 69 startblock += part_offset; 70 remainder = off & (uint64_t)(fs->dev_desc->blksz - 1); 71 72 if (fs->dev_desc == NULL) 73 return; 74 75 if ((startblock + (size >> log2blksz)) > 76 (part_offset + fs->total_sect)) { 77 printf("part_offset is " LBAFU "\n", part_offset); 78 printf("total_sector is %" PRIu64 "\n", fs->total_sect); 79 printf("error: overflow occurs\n"); 80 return; 81 } 82 83 if (remainder) { 84 if (fs->dev_desc->block_read) { 85 fs->dev_desc->block_read(fs->dev_desc->dev, 86 startblock, 1, sec_buf); 87 temp_ptr = sec_buf; 88 memcpy((temp_ptr + remainder), 89 (unsigned char *)buf, size); 90 fs->dev_desc->block_write(fs->dev_desc->dev, 91 startblock, 1, sec_buf); 92 } 93 } else { 94 if (size >> log2blksz != 0) { 95 fs->dev_desc->block_write(fs->dev_desc->dev, 96 startblock, 97 size >> log2blksz, 98 (unsigned long *)buf); 99 } else { 100 fs->dev_desc->block_read(fs->dev_desc->dev, 101 startblock, 1, sec_buf); 102 temp_ptr = sec_buf; 103 memcpy(temp_ptr, buf, size); 104 fs->dev_desc->block_write(fs->dev_desc->dev, 105 startblock, 1, 106 (unsigned long *)sec_buf); 107 } 108 } 109 } 110 111 static int _get_new_inode_no(unsigned char *buffer) 112 { 113 struct ext_filesystem *fs = get_fs(); 114 unsigned char input; 115 int operand, status; 116 int count = 1; 117 int j = 0; 118 119 /* get the blocksize of the filesystem */ 120 unsigned char *ptr = buffer; 121 while (*ptr == 255) { 122 ptr++; 123 count += 8; 124 if (count > ext4fs_root->sblock.inodes_per_group) 125 return -1; 126 } 127 128 for (j = 0; j < fs->blksz; j++) { 129 input = *ptr; 130 int i = 0; 131 while (i <= 7) { 132 operand = 1 << i; 133 status = input & operand; 134 if (status) { 135 i++; 136 count++; 137 } else { 138 *ptr |= operand; 139 return count; 140 } 141 } 142 ptr = ptr + 1; 143 } 144 145 return -1; 146 } 147 148 static int _get_new_blk_no(unsigned char *buffer) 149 { 150 unsigned char input; 151 int operand, status; 152 int count = 0; 153 int j = 0; 154 unsigned char *ptr = buffer; 155 struct ext_filesystem *fs = get_fs(); 156 157 if (fs->blksz != 1024) 158 count = 0; 159 else 160 count = 1; 161 162 while (*ptr == 255) { 163 ptr++; 164 count += 8; 165 if (count == (fs->blksz * 8)) 166 return -1; 167 } 168 169 for (j = 0; j < fs->blksz; j++) { 170 input = *ptr; 171 int i = 0; 172 while (i <= 7) { 173 operand = 1 << i; 174 status = input & operand; 175 if (status) { 176 i++; 177 count++; 178 } else { 179 *ptr |= operand; 180 return count; 181 } 182 } 183 ptr = ptr + 1; 184 } 185 186 return -1; 187 } 188 189 int ext4fs_set_block_bmap(long int blockno, unsigned char *buffer, int index) 190 { 191 int i, remainder, status; 192 unsigned char *ptr = buffer; 193 unsigned char operand; 194 i = blockno / 8; 195 remainder = blockno % 8; 196 int blocksize = EXT2_BLOCK_SIZE(ext4fs_root); 197 198 i = i - (index * blocksize); 199 if (blocksize != 1024) { 200 ptr = ptr + i; 201 operand = 1 << remainder; 202 status = *ptr & operand; 203 if (status) 204 return -1; 205 206 *ptr = *ptr | operand; 207 return 0; 208 } else { 209 if (remainder == 0) { 210 ptr = ptr + i - 1; 211 operand = (1 << 7); 212 } else { 213 ptr = ptr + i; 214 operand = (1 << (remainder - 1)); 215 } 216 status = *ptr & operand; 217 if (status) 218 return -1; 219 220 *ptr = *ptr | operand; 221 return 0; 222 } 223 } 224 225 void ext4fs_reset_block_bmap(long int blockno, unsigned char *buffer, int index) 226 { 227 int i, remainder, status; 228 unsigned char *ptr = buffer; 229 unsigned char operand; 230 i = blockno / 8; 231 remainder = blockno % 8; 232 int blocksize = EXT2_BLOCK_SIZE(ext4fs_root); 233 234 i = i - (index * blocksize); 235 if (blocksize != 1024) { 236 ptr = ptr + i; 237 operand = (1 << remainder); 238 status = *ptr & operand; 239 if (status) 240 *ptr = *ptr & ~(operand); 241 } else { 242 if (remainder == 0) { 243 ptr = ptr + i - 1; 244 operand = (1 << 7); 245 } else { 246 ptr = ptr + i; 247 operand = (1 << (remainder - 1)); 248 } 249 status = *ptr & operand; 250 if (status) 251 *ptr = *ptr & ~(operand); 252 } 253 } 254 255 int ext4fs_set_inode_bmap(int inode_no, unsigned char *buffer, int index) 256 { 257 int i, remainder, status; 258 unsigned char *ptr = buffer; 259 unsigned char operand; 260 261 inode_no -= (index * ext4fs_root->sblock.inodes_per_group); 262 i = inode_no / 8; 263 remainder = inode_no % 8; 264 if (remainder == 0) { 265 ptr = ptr + i - 1; 266 operand = (1 << 7); 267 } else { 268 ptr = ptr + i; 269 operand = (1 << (remainder - 1)); 270 } 271 status = *ptr & operand; 272 if (status) 273 return -1; 274 275 *ptr = *ptr | operand; 276 277 return 0; 278 } 279 280 void ext4fs_reset_inode_bmap(int inode_no, unsigned char *buffer, int index) 281 { 282 int i, remainder, status; 283 unsigned char *ptr = buffer; 284 unsigned char operand; 285 286 inode_no -= (index * ext4fs_root->sblock.inodes_per_group); 287 i = inode_no / 8; 288 remainder = inode_no % 8; 289 if (remainder == 0) { 290 ptr = ptr + i - 1; 291 operand = (1 << 7); 292 } else { 293 ptr = ptr + i; 294 operand = (1 << (remainder - 1)); 295 } 296 status = *ptr & operand; 297 if (status) 298 *ptr = *ptr & ~(operand); 299 } 300 301 int ext4fs_checksum_update(unsigned int i) 302 { 303 struct ext2_block_group *desc; 304 struct ext_filesystem *fs = get_fs(); 305 __u16 crc = 0; 306 307 desc = (struct ext2_block_group *)&fs->bgd[i]; 308 if (fs->sb->feature_ro_compat & EXT4_FEATURE_RO_COMPAT_GDT_CSUM) { 309 int offset = offsetof(struct ext2_block_group, bg_checksum); 310 311 crc = ext2fs_crc16(~0, fs->sb->unique_id, 312 sizeof(fs->sb->unique_id)); 313 crc = ext2fs_crc16(crc, &i, sizeof(i)); 314 crc = ext2fs_crc16(crc, desc, offset); 315 offset += sizeof(desc->bg_checksum); /* skip checksum */ 316 assert(offset == sizeof(*desc)); 317 } 318 319 return crc; 320 } 321 322 static int check_void_in_dentry(struct ext2_dirent *dir, char *filename) 323 { 324 int dentry_length; 325 int sizeof_void_space; 326 int new_entry_byte_reqd; 327 short padding_factor = 0; 328 329 if (dir->namelen % 4 != 0) 330 padding_factor = 4 - (dir->namelen % 4); 331 332 dentry_length = sizeof(struct ext2_dirent) + 333 dir->namelen + padding_factor; 334 sizeof_void_space = dir->direntlen - dentry_length; 335 if (sizeof_void_space == 0) 336 return 0; 337 338 padding_factor = 0; 339 if (strlen(filename) % 4 != 0) 340 padding_factor = 4 - (strlen(filename) % 4); 341 342 new_entry_byte_reqd = strlen(filename) + 343 sizeof(struct ext2_dirent) + padding_factor; 344 if (sizeof_void_space >= new_entry_byte_reqd) { 345 dir->direntlen = dentry_length; 346 return sizeof_void_space; 347 } 348 349 return 0; 350 } 351 352 void ext4fs_update_parent_dentry(char *filename, int *p_ino, int file_type) 353 { 354 unsigned int *zero_buffer = NULL; 355 char *root_first_block_buffer = NULL; 356 int direct_blk_idx; 357 long int root_blknr; 358 long int first_block_no_of_root = 0; 359 long int previous_blknr = -1; 360 int totalbytes = 0; 361 short int padding_factor = 0; 362 unsigned int new_entry_byte_reqd; 363 unsigned int last_entry_dirlen; 364 int sizeof_void_space = 0; 365 int templength = 0; 366 int inodeno; 367 int status; 368 struct ext_filesystem *fs = get_fs(); 369 /* directory entry */ 370 struct ext2_dirent *dir; 371 char *temp_dir = NULL; 372 373 zero_buffer = zalloc(fs->blksz); 374 if (!zero_buffer) { 375 printf("No Memory\n"); 376 return; 377 } 378 root_first_block_buffer = zalloc(fs->blksz); 379 if (!root_first_block_buffer) { 380 free(zero_buffer); 381 printf("No Memory\n"); 382 return; 383 } 384 restart: 385 386 /* read the block no allocated to a file */ 387 for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS; 388 direct_blk_idx++) { 389 root_blknr = read_allocated_block(g_parent_inode, 390 direct_blk_idx); 391 if (root_blknr == 0) { 392 first_block_no_of_root = previous_blknr; 393 break; 394 } 395 previous_blknr = root_blknr; 396 } 397 398 status = ext4fs_devread((lbaint_t)first_block_no_of_root 399 * fs->sect_perblk, 400 0, fs->blksz, root_first_block_buffer); 401 if (status == 0) 402 goto fail; 403 404 if (ext4fs_log_journal(root_first_block_buffer, first_block_no_of_root)) 405 goto fail; 406 dir = (struct ext2_dirent *)root_first_block_buffer; 407 totalbytes = 0; 408 while (dir->direntlen > 0) { 409 /* 410 * blocksize-totalbytes because last directory length 411 * i.e. dir->direntlen is free availble space in the 412 * block that means it is a last entry of directory 413 * entry 414 */ 415 416 /* traversing the each directory entry */ 417 if (fs->blksz - totalbytes == dir->direntlen) { 418 if (strlen(filename) % 4 != 0) 419 padding_factor = 4 - (strlen(filename) % 4); 420 421 new_entry_byte_reqd = strlen(filename) + 422 sizeof(struct ext2_dirent) + padding_factor; 423 padding_factor = 0; 424 /* 425 * update last directory entry length to its 426 * length because we are creating new directory 427 * entry 428 */ 429 if (dir->namelen % 4 != 0) 430 padding_factor = 4 - (dir->namelen % 4); 431 432 last_entry_dirlen = dir->namelen + 433 sizeof(struct ext2_dirent) + padding_factor; 434 if ((fs->blksz - totalbytes - last_entry_dirlen) < 435 new_entry_byte_reqd) { 436 printf("1st Block Full:Allocate new block\n"); 437 438 if (direct_blk_idx == INDIRECT_BLOCKS - 1) { 439 printf("Directory exceeds limit\n"); 440 goto fail; 441 } 442 g_parent_inode->b.blocks.dir_blocks 443 [direct_blk_idx] = ext4fs_get_new_blk_no(); 444 if (g_parent_inode->b.blocks.dir_blocks 445 [direct_blk_idx] == -1) { 446 printf("no block left to assign\n"); 447 goto fail; 448 } 449 put_ext4(((uint64_t) 450 ((uint64_t)g_parent_inode->b. 451 blocks.dir_blocks[direct_blk_idx] * 452 (uint64_t)fs->blksz)), zero_buffer, fs->blksz); 453 g_parent_inode->size = 454 g_parent_inode->size + fs->blksz; 455 g_parent_inode->blockcnt = 456 g_parent_inode->blockcnt + fs->sect_perblk; 457 if (ext4fs_put_metadata 458 (root_first_block_buffer, 459 first_block_no_of_root)) 460 goto fail; 461 goto restart; 462 } 463 dir->direntlen = last_entry_dirlen; 464 break; 465 } 466 467 templength = dir->direntlen; 468 totalbytes = totalbytes + templength; 469 sizeof_void_space = check_void_in_dentry(dir, filename); 470 if (sizeof_void_space) 471 break; 472 473 dir = (struct ext2_dirent *)((char *)dir + templength); 474 } 475 476 /* make a pointer ready for creating next directory entry */ 477 templength = dir->direntlen; 478 totalbytes = totalbytes + templength; 479 dir = (struct ext2_dirent *)((char *)dir + templength); 480 481 /* get the next available inode number */ 482 inodeno = ext4fs_get_new_inode_no(); 483 if (inodeno == -1) { 484 printf("no inode left to assign\n"); 485 goto fail; 486 } 487 dir->inode = inodeno; 488 if (sizeof_void_space) 489 dir->direntlen = sizeof_void_space; 490 else 491 dir->direntlen = fs->blksz - totalbytes; 492 493 dir->namelen = strlen(filename); 494 dir->filetype = FILETYPE_REG; /* regular file */ 495 temp_dir = (char *)dir; 496 temp_dir = temp_dir + sizeof(struct ext2_dirent); 497 memcpy(temp_dir, filename, strlen(filename)); 498 499 *p_ino = inodeno; 500 501 /* update or write the 1st block of root inode */ 502 if (ext4fs_put_metadata(root_first_block_buffer, 503 first_block_no_of_root)) 504 goto fail; 505 506 fail: 507 free(zero_buffer); 508 free(root_first_block_buffer); 509 } 510 511 static int search_dir(struct ext2_inode *parent_inode, char *dirname) 512 { 513 int status; 514 int inodeno; 515 int totalbytes; 516 int templength; 517 int direct_blk_idx; 518 long int blknr; 519 int found = 0; 520 char *ptr = NULL; 521 unsigned char *block_buffer = NULL; 522 struct ext2_dirent *dir = NULL; 523 struct ext2_dirent *previous_dir = NULL; 524 struct ext_filesystem *fs = get_fs(); 525 526 /* read the block no allocated to a file */ 527 for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS; 528 direct_blk_idx++) { 529 blknr = read_allocated_block(parent_inode, direct_blk_idx); 530 if (blknr == 0) 531 goto fail; 532 533 /* read the blocks of parenet inode */ 534 block_buffer = zalloc(fs->blksz); 535 if (!block_buffer) 536 goto fail; 537 538 status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 539 0, fs->blksz, (char *)block_buffer); 540 if (status == 0) 541 goto fail; 542 543 dir = (struct ext2_dirent *)block_buffer; 544 ptr = (char *)dir; 545 totalbytes = 0; 546 while (dir->direntlen >= 0) { 547 /* 548 * blocksize-totalbytes because last directory 549 * length i.e.,*dir->direntlen is free availble 550 * space in the block that means 551 * it is a last entry of directory entry 552 */ 553 if (strlen(dirname) == dir->namelen) { 554 if (strncmp(dirname, ptr + 555 sizeof(struct ext2_dirent), 556 dir->namelen) == 0) { 557 previous_dir->direntlen += 558 dir->direntlen; 559 inodeno = dir->inode; 560 dir->inode = 0; 561 found = 1; 562 break; 563 } 564 } 565 566 if (fs->blksz - totalbytes == dir->direntlen) 567 break; 568 569 /* traversing the each directory entry */ 570 templength = dir->direntlen; 571 totalbytes = totalbytes + templength; 572 previous_dir = dir; 573 dir = (struct ext2_dirent *)((char *)dir + templength); 574 ptr = (char *)dir; 575 } 576 577 if (found == 1) { 578 free(block_buffer); 579 block_buffer = NULL; 580 return inodeno; 581 } 582 583 free(block_buffer); 584 block_buffer = NULL; 585 } 586 587 fail: 588 free(block_buffer); 589 590 return -1; 591 } 592 593 static int find_dir_depth(char *dirname) 594 { 595 char *token = strtok(dirname, "/"); 596 int count = 0; 597 while (token != NULL) { 598 token = strtok(NULL, "/"); 599 count++; 600 } 601 return count + 1 + 1; 602 /* 603 * for example for string /home/temp 604 * depth=home(1)+temp(1)+1 extra for NULL; 605 * so count is 4; 606 */ 607 } 608 609 static int parse_path(char **arr, char *dirname) 610 { 611 char *token = strtok(dirname, "/"); 612 int i = 0; 613 614 /* add root */ 615 arr[i] = zalloc(strlen("/") + 1); 616 if (!arr[i]) 617 return -ENOMEM; 618 memcpy(arr[i++], "/", strlen("/")); 619 620 /* add each path entry after root */ 621 while (token != NULL) { 622 arr[i] = zalloc(strlen(token) + 1); 623 if (!arr[i]) 624 return -ENOMEM; 625 memcpy(arr[i++], token, strlen(token)); 626 token = strtok(NULL, "/"); 627 } 628 arr[i] = NULL; 629 630 return 0; 631 } 632 633 int ext4fs_iget(int inode_no, struct ext2_inode *inode) 634 { 635 if (ext4fs_read_inode(ext4fs_root, inode_no, inode) == 0) 636 return -1; 637 638 return 0; 639 } 640 641 /* 642 * Function: ext4fs_get_parent_inode_num 643 * Return Value: inode Number of the parent directory of file/Directory to be 644 * created 645 * dirname : Input parmater, input path name of the file/directory to be created 646 * dname : Output parameter, to be filled with the name of the directory 647 * extracted from dirname 648 */ 649 int ext4fs_get_parent_inode_num(const char *dirname, char *dname, int flags) 650 { 651 int i; 652 int depth = 0; 653 int matched_inode_no; 654 int result_inode_no = -1; 655 char **ptr = NULL; 656 char *depth_dirname = NULL; 657 char *parse_dirname = NULL; 658 struct ext2_inode *parent_inode = NULL; 659 struct ext2_inode *first_inode = NULL; 660 struct ext2_inode temp_inode; 661 662 if (*dirname != '/') { 663 printf("Please supply Absolute path\n"); 664 return -1; 665 } 666 667 /* TODO: input validation make equivalent to linux */ 668 depth_dirname = zalloc(strlen(dirname) + 1); 669 if (!depth_dirname) 670 return -ENOMEM; 671 672 memcpy(depth_dirname, dirname, strlen(dirname)); 673 depth = find_dir_depth(depth_dirname); 674 parse_dirname = zalloc(strlen(dirname) + 1); 675 if (!parse_dirname) 676 goto fail; 677 memcpy(parse_dirname, dirname, strlen(dirname)); 678 679 /* allocate memory for each directory level */ 680 ptr = zalloc((depth) * sizeof(char *)); 681 if (!ptr) 682 goto fail; 683 if (parse_path(ptr, parse_dirname)) 684 goto fail; 685 parent_inode = zalloc(sizeof(struct ext2_inode)); 686 if (!parent_inode) 687 goto fail; 688 first_inode = zalloc(sizeof(struct ext2_inode)); 689 if (!first_inode) 690 goto fail; 691 memcpy(parent_inode, ext4fs_root->inode, sizeof(struct ext2_inode)); 692 memcpy(first_inode, parent_inode, sizeof(struct ext2_inode)); 693 if (flags & F_FILE) 694 result_inode_no = EXT2_ROOT_INO; 695 for (i = 1; i < depth; i++) { 696 matched_inode_no = search_dir(parent_inode, ptr[i]); 697 if (matched_inode_no == -1) { 698 if (ptr[i + 1] == NULL && i == 1) { 699 result_inode_no = EXT2_ROOT_INO; 700 goto end; 701 } else { 702 if (ptr[i + 1] == NULL) 703 break; 704 printf("Invalid path\n"); 705 result_inode_no = -1; 706 goto fail; 707 } 708 } else { 709 if (ptr[i + 1] != NULL) { 710 memset(parent_inode, '\0', 711 sizeof(struct ext2_inode)); 712 if (ext4fs_iget(matched_inode_no, 713 parent_inode)) { 714 result_inode_no = -1; 715 goto fail; 716 } 717 result_inode_no = matched_inode_no; 718 } else { 719 break; 720 } 721 } 722 } 723 724 end: 725 if (i == 1) 726 matched_inode_no = search_dir(first_inode, ptr[i]); 727 else 728 matched_inode_no = search_dir(parent_inode, ptr[i]); 729 730 if (matched_inode_no != -1) { 731 ext4fs_iget(matched_inode_no, &temp_inode); 732 if (temp_inode.mode & S_IFDIR) { 733 printf("It is a Directory\n"); 734 result_inode_no = -1; 735 goto fail; 736 } 737 } 738 739 if (strlen(ptr[i]) > 256) { 740 result_inode_no = -1; 741 goto fail; 742 } 743 memcpy(dname, ptr[i], strlen(ptr[i])); 744 745 fail: 746 free(depth_dirname); 747 free(parse_dirname); 748 for (i = 0; i < depth; i++) { 749 if (!ptr[i]) 750 break; 751 free(ptr[i]); 752 } 753 free(ptr); 754 free(parent_inode); 755 free(first_inode); 756 757 return result_inode_no; 758 } 759 760 static int check_filename(char *filename, unsigned int blknr) 761 { 762 unsigned int first_block_no_of_root; 763 int totalbytes = 0; 764 int templength = 0; 765 int status, inodeno; 766 int found = 0; 767 char *root_first_block_buffer = NULL; 768 char *root_first_block_addr = NULL; 769 struct ext2_dirent *dir = NULL; 770 struct ext2_dirent *previous_dir = NULL; 771 char *ptr = NULL; 772 struct ext_filesystem *fs = get_fs(); 773 int ret = -1; 774 775 /* get the first block of root */ 776 first_block_no_of_root = blknr; 777 root_first_block_buffer = zalloc(fs->blksz); 778 if (!root_first_block_buffer) 779 return -ENOMEM; 780 root_first_block_addr = root_first_block_buffer; 781 status = ext4fs_devread((lbaint_t)first_block_no_of_root * 782 fs->sect_perblk, 0, 783 fs->blksz, root_first_block_buffer); 784 if (status == 0) 785 goto fail; 786 787 if (ext4fs_log_journal(root_first_block_buffer, first_block_no_of_root)) 788 goto fail; 789 dir = (struct ext2_dirent *)root_first_block_buffer; 790 ptr = (char *)dir; 791 totalbytes = 0; 792 while (dir->direntlen >= 0) { 793 /* 794 * blocksize-totalbytes because last 795 * directory length i.e., *dir->direntlen 796 * is free availble space in the block that 797 * means it is a last entry of directory entry 798 */ 799 if (strlen(filename) == dir->namelen) { 800 if (strncmp(filename, ptr + sizeof(struct ext2_dirent), 801 dir->namelen) == 0) { 802 printf("file found deleting\n"); 803 previous_dir->direntlen += dir->direntlen; 804 inodeno = dir->inode; 805 dir->inode = 0; 806 found = 1; 807 break; 808 } 809 } 810 811 if (fs->blksz - totalbytes == dir->direntlen) 812 break; 813 814 /* traversing the each directory entry */ 815 templength = dir->direntlen; 816 totalbytes = totalbytes + templength; 817 previous_dir = dir; 818 dir = (struct ext2_dirent *)((char *)dir + templength); 819 ptr = (char *)dir; 820 } 821 822 823 if (found == 1) { 824 if (ext4fs_put_metadata(root_first_block_addr, 825 first_block_no_of_root)) 826 goto fail; 827 ret = inodeno; 828 } 829 fail: 830 free(root_first_block_buffer); 831 832 return ret; 833 } 834 835 int ext4fs_filename_check(char *filename) 836 { 837 short direct_blk_idx = 0; 838 long int blknr = -1; 839 int inodeno = -1; 840 841 /* read the block no allocated to a file */ 842 for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS; 843 direct_blk_idx++) { 844 blknr = read_allocated_block(g_parent_inode, direct_blk_idx); 845 if (blknr == 0) 846 break; 847 inodeno = check_filename(filename, blknr); 848 if (inodeno != -1) 849 return inodeno; 850 } 851 852 return -1; 853 } 854 855 long int ext4fs_get_new_blk_no(void) 856 { 857 short i; 858 short status; 859 int remainder; 860 unsigned int bg_idx; 861 static int prev_bg_bitmap_index = -1; 862 unsigned int blk_per_grp = ext4fs_root->sblock.blocks_per_group; 863 struct ext_filesystem *fs = get_fs(); 864 char *journal_buffer = zalloc(fs->blksz); 865 char *zero_buffer = zalloc(fs->blksz); 866 if (!journal_buffer || !zero_buffer) 867 goto fail; 868 struct ext2_block_group *bgd = (struct ext2_block_group *)fs->gdtable; 869 870 if (fs->first_pass_bbmap == 0) { 871 for (i = 0; i < fs->no_blkgrp; i++) { 872 if (bgd[i].free_blocks) { 873 if (bgd[i].bg_flags & EXT4_BG_BLOCK_UNINIT) { 874 put_ext4(((uint64_t) ((uint64_t)bgd[i].block_id * 875 (uint64_t)fs->blksz)), 876 zero_buffer, fs->blksz); 877 bgd[i].bg_flags = 878 bgd[i]. 879 bg_flags & ~EXT4_BG_BLOCK_UNINIT; 880 memcpy(fs->blk_bmaps[i], zero_buffer, 881 fs->blksz); 882 } 883 fs->curr_blkno = 884 _get_new_blk_no(fs->blk_bmaps[i]); 885 if (fs->curr_blkno == -1) 886 /* if block bitmap is completely fill */ 887 continue; 888 fs->curr_blkno = fs->curr_blkno + 889 (i * fs->blksz * 8); 890 fs->first_pass_bbmap++; 891 bgd[i].free_blocks--; 892 fs->sb->free_blocks--; 893 status = ext4fs_devread((lbaint_t) 894 bgd[i].block_id * 895 fs->sect_perblk, 0, 896 fs->blksz, 897 journal_buffer); 898 if (status == 0) 899 goto fail; 900 if (ext4fs_log_journal(journal_buffer, 901 bgd[i].block_id)) 902 goto fail; 903 goto success; 904 } else { 905 debug("no space left on block group %d\n", i); 906 } 907 } 908 909 goto fail; 910 } else { 911 restart: 912 fs->curr_blkno++; 913 /* get the blockbitmap index respective to blockno */ 914 bg_idx = fs->curr_blkno / blk_per_grp; 915 if (fs->blksz == 1024) { 916 remainder = fs->curr_blkno % blk_per_grp; 917 if (!remainder) 918 bg_idx--; 919 } 920 921 /* 922 * To skip completely filled block group bitmaps 923 * Optimize the block allocation 924 */ 925 if (bg_idx >= fs->no_blkgrp) 926 goto fail; 927 928 if (bgd[bg_idx].free_blocks == 0) { 929 debug("block group %u is full. Skipping\n", bg_idx); 930 fs->curr_blkno = fs->curr_blkno + blk_per_grp; 931 fs->curr_blkno--; 932 goto restart; 933 } 934 935 if (bgd[bg_idx].bg_flags & EXT4_BG_BLOCK_UNINIT) { 936 memset(zero_buffer, '\0', fs->blksz); 937 put_ext4(((uint64_t) ((uint64_t)bgd[bg_idx].block_id * 938 (uint64_t)fs->blksz)), zero_buffer, fs->blksz); 939 memcpy(fs->blk_bmaps[bg_idx], zero_buffer, fs->blksz); 940 bgd[bg_idx].bg_flags = bgd[bg_idx].bg_flags & 941 ~EXT4_BG_BLOCK_UNINIT; 942 } 943 944 if (ext4fs_set_block_bmap(fs->curr_blkno, fs->blk_bmaps[bg_idx], 945 bg_idx) != 0) { 946 debug("going for restart for the block no %ld %u\n", 947 fs->curr_blkno, bg_idx); 948 goto restart; 949 } 950 951 /* journal backup */ 952 if (prev_bg_bitmap_index != bg_idx) { 953 memset(journal_buffer, '\0', fs->blksz); 954 status = ext4fs_devread((lbaint_t)bgd[bg_idx].block_id 955 * fs->sect_perblk, 956 0, fs->blksz, journal_buffer); 957 if (status == 0) 958 goto fail; 959 if (ext4fs_log_journal(journal_buffer, 960 bgd[bg_idx].block_id)) 961 goto fail; 962 963 prev_bg_bitmap_index = bg_idx; 964 } 965 bgd[bg_idx].free_blocks--; 966 fs->sb->free_blocks--; 967 goto success; 968 } 969 success: 970 free(journal_buffer); 971 free(zero_buffer); 972 973 return fs->curr_blkno; 974 fail: 975 free(journal_buffer); 976 free(zero_buffer); 977 978 return -1; 979 } 980 981 int ext4fs_get_new_inode_no(void) 982 { 983 short i; 984 short status; 985 unsigned int ibmap_idx; 986 static int prev_inode_bitmap_index = -1; 987 unsigned int inodes_per_grp = ext4fs_root->sblock.inodes_per_group; 988 struct ext_filesystem *fs = get_fs(); 989 char *journal_buffer = zalloc(fs->blksz); 990 char *zero_buffer = zalloc(fs->blksz); 991 if (!journal_buffer || !zero_buffer) 992 goto fail; 993 struct ext2_block_group *bgd = (struct ext2_block_group *)fs->gdtable; 994 995 if (fs->first_pass_ibmap == 0) { 996 for (i = 0; i < fs->no_blkgrp; i++) { 997 if (bgd[i].free_inodes) { 998 if (bgd[i].bg_itable_unused != 999 bgd[i].free_inodes) 1000 bgd[i].bg_itable_unused = 1001 bgd[i].free_inodes; 1002 if (bgd[i].bg_flags & EXT4_BG_INODE_UNINIT) { 1003 put_ext4(((uint64_t) 1004 ((uint64_t)bgd[i].inode_id * 1005 (uint64_t)fs->blksz)), 1006 zero_buffer, fs->blksz); 1007 bgd[i].bg_flags = bgd[i].bg_flags & 1008 ~EXT4_BG_INODE_UNINIT; 1009 memcpy(fs->inode_bmaps[i], 1010 zero_buffer, fs->blksz); 1011 } 1012 fs->curr_inode_no = 1013 _get_new_inode_no(fs->inode_bmaps[i]); 1014 if (fs->curr_inode_no == -1) 1015 /* if block bitmap is completely fill */ 1016 continue; 1017 fs->curr_inode_no = fs->curr_inode_no + 1018 (i * inodes_per_grp); 1019 fs->first_pass_ibmap++; 1020 bgd[i].free_inodes--; 1021 bgd[i].bg_itable_unused--; 1022 fs->sb->free_inodes--; 1023 status = ext4fs_devread((lbaint_t) 1024 bgd[i].inode_id * 1025 fs->sect_perblk, 0, 1026 fs->blksz, 1027 journal_buffer); 1028 if (status == 0) 1029 goto fail; 1030 if (ext4fs_log_journal(journal_buffer, 1031 bgd[i].inode_id)) 1032 goto fail; 1033 goto success; 1034 } else 1035 debug("no inode left on block group %d\n", i); 1036 } 1037 goto fail; 1038 } else { 1039 restart: 1040 fs->curr_inode_no++; 1041 /* get the blockbitmap index respective to blockno */ 1042 ibmap_idx = fs->curr_inode_no / inodes_per_grp; 1043 if (bgd[ibmap_idx].bg_flags & EXT4_BG_INODE_UNINIT) { 1044 memset(zero_buffer, '\0', fs->blksz); 1045 put_ext4(((uint64_t) ((uint64_t)bgd[ibmap_idx].inode_id * 1046 (uint64_t)fs->blksz)), zero_buffer, 1047 fs->blksz); 1048 bgd[ibmap_idx].bg_flags = 1049 bgd[ibmap_idx].bg_flags & ~EXT4_BG_INODE_UNINIT; 1050 memcpy(fs->inode_bmaps[ibmap_idx], zero_buffer, 1051 fs->blksz); 1052 } 1053 1054 if (ext4fs_set_inode_bmap(fs->curr_inode_no, 1055 fs->inode_bmaps[ibmap_idx], 1056 ibmap_idx) != 0) { 1057 debug("going for restart for the block no %d %u\n", 1058 fs->curr_inode_no, ibmap_idx); 1059 goto restart; 1060 } 1061 1062 /* journal backup */ 1063 if (prev_inode_bitmap_index != ibmap_idx) { 1064 memset(journal_buffer, '\0', fs->blksz); 1065 status = ext4fs_devread((lbaint_t) 1066 bgd[ibmap_idx].inode_id 1067 * fs->sect_perblk, 1068 0, fs->blksz, journal_buffer); 1069 if (status == 0) 1070 goto fail; 1071 if (ext4fs_log_journal(journal_buffer, 1072 bgd[ibmap_idx].inode_id)) 1073 goto fail; 1074 prev_inode_bitmap_index = ibmap_idx; 1075 } 1076 if (bgd[ibmap_idx].bg_itable_unused != 1077 bgd[ibmap_idx].free_inodes) 1078 bgd[ibmap_idx].bg_itable_unused = 1079 bgd[ibmap_idx].free_inodes; 1080 bgd[ibmap_idx].free_inodes--; 1081 bgd[ibmap_idx].bg_itable_unused--; 1082 fs->sb->free_inodes--; 1083 goto success; 1084 } 1085 1086 success: 1087 free(journal_buffer); 1088 free(zero_buffer); 1089 1090 return fs->curr_inode_no; 1091 fail: 1092 free(journal_buffer); 1093 free(zero_buffer); 1094 1095 return -1; 1096 1097 } 1098 1099 1100 static void alloc_single_indirect_block(struct ext2_inode *file_inode, 1101 unsigned int *total_remaining_blocks, 1102 unsigned int *no_blks_reqd) 1103 { 1104 short i; 1105 short status; 1106 long int actual_block_no; 1107 long int si_blockno; 1108 /* si :single indirect */ 1109 unsigned int *si_buffer = NULL; 1110 unsigned int *si_start_addr = NULL; 1111 struct ext_filesystem *fs = get_fs(); 1112 1113 if (*total_remaining_blocks != 0) { 1114 si_buffer = zalloc(fs->blksz); 1115 if (!si_buffer) { 1116 printf("No Memory\n"); 1117 return; 1118 } 1119 si_start_addr = si_buffer; 1120 si_blockno = ext4fs_get_new_blk_no(); 1121 if (si_blockno == -1) { 1122 printf("no block left to assign\n"); 1123 goto fail; 1124 } 1125 (*no_blks_reqd)++; 1126 debug("SIPB %ld: %u\n", si_blockno, *total_remaining_blocks); 1127 1128 status = ext4fs_devread((lbaint_t)si_blockno * fs->sect_perblk, 1129 0, fs->blksz, (char *)si_buffer); 1130 memset(si_buffer, '\0', fs->blksz); 1131 if (status == 0) 1132 goto fail; 1133 1134 for (i = 0; i < (fs->blksz / sizeof(int)); i++) { 1135 actual_block_no = ext4fs_get_new_blk_no(); 1136 if (actual_block_no == -1) { 1137 printf("no block left to assign\n"); 1138 goto fail; 1139 } 1140 *si_buffer = actual_block_no; 1141 debug("SIAB %u: %u\n", *si_buffer, 1142 *total_remaining_blocks); 1143 1144 si_buffer++; 1145 (*total_remaining_blocks)--; 1146 if (*total_remaining_blocks == 0) 1147 break; 1148 } 1149 1150 /* write the block to disk */ 1151 put_ext4(((uint64_t) ((uint64_t)si_blockno * (uint64_t)fs->blksz)), 1152 si_start_addr, fs->blksz); 1153 file_inode->b.blocks.indir_block = si_blockno; 1154 } 1155 fail: 1156 free(si_start_addr); 1157 } 1158 1159 static void alloc_double_indirect_block(struct ext2_inode *file_inode, 1160 unsigned int *total_remaining_blocks, 1161 unsigned int *no_blks_reqd) 1162 { 1163 short i; 1164 short j; 1165 short status; 1166 long int actual_block_no; 1167 /* di:double indirect */ 1168 long int di_blockno_parent; 1169 long int di_blockno_child; 1170 unsigned int *di_parent_buffer = NULL; 1171 unsigned int *di_child_buff = NULL; 1172 unsigned int *di_block_start_addr = NULL; 1173 unsigned int *di_child_buff_start = NULL; 1174 struct ext_filesystem *fs = get_fs(); 1175 1176 if (*total_remaining_blocks != 0) { 1177 /* double indirect parent block connecting to inode */ 1178 di_blockno_parent = ext4fs_get_new_blk_no(); 1179 if (di_blockno_parent == -1) { 1180 printf("no block left to assign\n"); 1181 goto fail; 1182 } 1183 di_parent_buffer = zalloc(fs->blksz); 1184 if (!di_parent_buffer) 1185 goto fail; 1186 1187 di_block_start_addr = di_parent_buffer; 1188 (*no_blks_reqd)++; 1189 debug("DIPB %ld: %u\n", di_blockno_parent, 1190 *total_remaining_blocks); 1191 1192 status = ext4fs_devread((lbaint_t)di_blockno_parent * 1193 fs->sect_perblk, 0, 1194 fs->blksz, (char *)di_parent_buffer); 1195 1196 if (!status) { 1197 printf("%s: Device read error!\n", __func__); 1198 goto fail; 1199 } 1200 memset(di_parent_buffer, '\0', fs->blksz); 1201 1202 /* 1203 * start:for each double indirect parent 1204 * block create one more block 1205 */ 1206 for (i = 0; i < (fs->blksz / sizeof(int)); i++) { 1207 di_blockno_child = ext4fs_get_new_blk_no(); 1208 if (di_blockno_child == -1) { 1209 printf("no block left to assign\n"); 1210 goto fail; 1211 } 1212 di_child_buff = zalloc(fs->blksz); 1213 if (!di_child_buff) 1214 goto fail; 1215 1216 di_child_buff_start = di_child_buff; 1217 *di_parent_buffer = di_blockno_child; 1218 di_parent_buffer++; 1219 (*no_blks_reqd)++; 1220 debug("DICB %ld: %u\n", di_blockno_child, 1221 *total_remaining_blocks); 1222 1223 status = ext4fs_devread((lbaint_t)di_blockno_child * 1224 fs->sect_perblk, 0, 1225 fs->blksz, 1226 (char *)di_child_buff); 1227 1228 if (!status) { 1229 printf("%s: Device read error!\n", __func__); 1230 goto fail; 1231 } 1232 memset(di_child_buff, '\0', fs->blksz); 1233 /* filling of actual datablocks for each child */ 1234 for (j = 0; j < (fs->blksz / sizeof(int)); j++) { 1235 actual_block_no = ext4fs_get_new_blk_no(); 1236 if (actual_block_no == -1) { 1237 printf("no block left to assign\n"); 1238 goto fail; 1239 } 1240 *di_child_buff = actual_block_no; 1241 debug("DIAB %ld: %u\n", actual_block_no, 1242 *total_remaining_blocks); 1243 1244 di_child_buff++; 1245 (*total_remaining_blocks)--; 1246 if (*total_remaining_blocks == 0) 1247 break; 1248 } 1249 /* write the block table */ 1250 put_ext4(((uint64_t) ((uint64_t)di_blockno_child * (uint64_t)fs->blksz)), 1251 di_child_buff_start, fs->blksz); 1252 free(di_child_buff_start); 1253 di_child_buff_start = NULL; 1254 1255 if (*total_remaining_blocks == 0) 1256 break; 1257 } 1258 put_ext4(((uint64_t) ((uint64_t)di_blockno_parent * (uint64_t)fs->blksz)), 1259 di_block_start_addr, fs->blksz); 1260 file_inode->b.blocks.double_indir_block = di_blockno_parent; 1261 } 1262 fail: 1263 free(di_block_start_addr); 1264 } 1265 1266 static void alloc_triple_indirect_block(struct ext2_inode *file_inode, 1267 unsigned int *total_remaining_blocks, 1268 unsigned int *no_blks_reqd) 1269 { 1270 short i; 1271 short j; 1272 short k; 1273 long int actual_block_no; 1274 /* ti: Triple Indirect */ 1275 long int ti_gp_blockno; 1276 long int ti_parent_blockno; 1277 long int ti_child_blockno; 1278 unsigned int *ti_gp_buff = NULL; 1279 unsigned int *ti_parent_buff = NULL; 1280 unsigned int *ti_child_buff = NULL; 1281 unsigned int *ti_gp_buff_start_addr = NULL; 1282 unsigned int *ti_pbuff_start_addr = NULL; 1283 unsigned int *ti_cbuff_start_addr = NULL; 1284 struct ext_filesystem *fs = get_fs(); 1285 if (*total_remaining_blocks != 0) { 1286 /* triple indirect grand parent block connecting to inode */ 1287 ti_gp_blockno = ext4fs_get_new_blk_no(); 1288 if (ti_gp_blockno == -1) { 1289 printf("no block left to assign\n"); 1290 goto fail; 1291 } 1292 ti_gp_buff = zalloc(fs->blksz); 1293 if (!ti_gp_buff) 1294 goto fail; 1295 1296 ti_gp_buff_start_addr = ti_gp_buff; 1297 (*no_blks_reqd)++; 1298 debug("TIGPB %ld: %u\n", ti_gp_blockno, 1299 *total_remaining_blocks); 1300 1301 /* for each 4 byte grand parent entry create one more block */ 1302 for (i = 0; i < (fs->blksz / sizeof(int)); i++) { 1303 ti_parent_blockno = ext4fs_get_new_blk_no(); 1304 if (ti_parent_blockno == -1) { 1305 printf("no block left to assign\n"); 1306 goto fail; 1307 } 1308 ti_parent_buff = zalloc(fs->blksz); 1309 if (!ti_parent_buff) 1310 goto fail; 1311 1312 ti_pbuff_start_addr = ti_parent_buff; 1313 *ti_gp_buff = ti_parent_blockno; 1314 ti_gp_buff++; 1315 (*no_blks_reqd)++; 1316 debug("TIPB %ld: %u\n", ti_parent_blockno, 1317 *total_remaining_blocks); 1318 1319 /* for each 4 byte entry parent create one more block */ 1320 for (j = 0; j < (fs->blksz / sizeof(int)); j++) { 1321 ti_child_blockno = ext4fs_get_new_blk_no(); 1322 if (ti_child_blockno == -1) { 1323 printf("no block left assign\n"); 1324 goto fail; 1325 } 1326 ti_child_buff = zalloc(fs->blksz); 1327 if (!ti_child_buff) 1328 goto fail; 1329 1330 ti_cbuff_start_addr = ti_child_buff; 1331 *ti_parent_buff = ti_child_blockno; 1332 ti_parent_buff++; 1333 (*no_blks_reqd)++; 1334 debug("TICB %ld: %u\n", ti_parent_blockno, 1335 *total_remaining_blocks); 1336 1337 /* fill actual datablocks for each child */ 1338 for (k = 0; k < (fs->blksz / sizeof(int)); 1339 k++) { 1340 actual_block_no = 1341 ext4fs_get_new_blk_no(); 1342 if (actual_block_no == -1) { 1343 printf("no block left\n"); 1344 goto fail; 1345 } 1346 *ti_child_buff = actual_block_no; 1347 debug("TIAB %ld: %u\n", actual_block_no, 1348 *total_remaining_blocks); 1349 1350 ti_child_buff++; 1351 (*total_remaining_blocks)--; 1352 if (*total_remaining_blocks == 0) 1353 break; 1354 } 1355 /* write the child block */ 1356 put_ext4(((uint64_t) ((uint64_t)ti_child_blockno * 1357 (uint64_t)fs->blksz)), 1358 ti_cbuff_start_addr, fs->blksz); 1359 free(ti_cbuff_start_addr); 1360 1361 if (*total_remaining_blocks == 0) 1362 break; 1363 } 1364 /* write the parent block */ 1365 put_ext4(((uint64_t) ((uint64_t)ti_parent_blockno * (uint64_t)fs->blksz)), 1366 ti_pbuff_start_addr, fs->blksz); 1367 free(ti_pbuff_start_addr); 1368 1369 if (*total_remaining_blocks == 0) 1370 break; 1371 } 1372 /* write the grand parent block */ 1373 put_ext4(((uint64_t) ((uint64_t)ti_gp_blockno * (uint64_t)fs->blksz)), 1374 ti_gp_buff_start_addr, fs->blksz); 1375 file_inode->b.blocks.triple_indir_block = ti_gp_blockno; 1376 } 1377 fail: 1378 free(ti_gp_buff_start_addr); 1379 } 1380 1381 void ext4fs_allocate_blocks(struct ext2_inode *file_inode, 1382 unsigned int total_remaining_blocks, 1383 unsigned int *total_no_of_block) 1384 { 1385 short i; 1386 long int direct_blockno; 1387 unsigned int no_blks_reqd = 0; 1388 1389 /* allocation of direct blocks */ 1390 for (i = 0; total_remaining_blocks && i < INDIRECT_BLOCKS; i++) { 1391 direct_blockno = ext4fs_get_new_blk_no(); 1392 if (direct_blockno == -1) { 1393 printf("no block left to assign\n"); 1394 return; 1395 } 1396 file_inode->b.blocks.dir_blocks[i] = direct_blockno; 1397 debug("DB %ld: %u\n", direct_blockno, total_remaining_blocks); 1398 1399 total_remaining_blocks--; 1400 } 1401 1402 alloc_single_indirect_block(file_inode, &total_remaining_blocks, 1403 &no_blks_reqd); 1404 alloc_double_indirect_block(file_inode, &total_remaining_blocks, 1405 &no_blks_reqd); 1406 alloc_triple_indirect_block(file_inode, &total_remaining_blocks, 1407 &no_blks_reqd); 1408 *total_no_of_block += no_blks_reqd; 1409 } 1410 1411 #endif 1412 1413 static struct ext4_extent_header *ext4fs_get_extent_block 1414 (struct ext2_data *data, char *buf, 1415 struct ext4_extent_header *ext_block, 1416 uint32_t fileblock, int log2_blksz) 1417 { 1418 struct ext4_extent_idx *index; 1419 unsigned long long block; 1420 int blksz = EXT2_BLOCK_SIZE(data); 1421 int i; 1422 1423 while (1) { 1424 index = (struct ext4_extent_idx *)(ext_block + 1); 1425 1426 if (le16_to_cpu(ext_block->eh_magic) != EXT4_EXT_MAGIC) 1427 return 0; 1428 1429 if (ext_block->eh_depth == 0) 1430 return ext_block; 1431 i = -1; 1432 do { 1433 i++; 1434 if (i >= le16_to_cpu(ext_block->eh_entries)) 1435 break; 1436 } while (fileblock >= le32_to_cpu(index[i].ei_block)); 1437 1438 if (--i < 0) 1439 return 0; 1440 1441 block = le16_to_cpu(index[i].ei_leaf_hi); 1442 block = (block << 32) + le32_to_cpu(index[i].ei_leaf_lo); 1443 1444 if (ext4fs_devread((lbaint_t)block << log2_blksz, 0, blksz, 1445 buf)) 1446 ext_block = (struct ext4_extent_header *)buf; 1447 else 1448 return 0; 1449 } 1450 } 1451 1452 static int ext4fs_blockgroup 1453 (struct ext2_data *data, int group, struct ext2_block_group *blkgrp) 1454 { 1455 long int blkno; 1456 unsigned int blkoff, desc_per_blk; 1457 int log2blksz = get_fs()->dev_desc->log2blksz; 1458 1459 desc_per_blk = EXT2_BLOCK_SIZE(data) / sizeof(struct ext2_block_group); 1460 1461 blkno = __le32_to_cpu(data->sblock.first_data_block) + 1 + 1462 group / desc_per_blk; 1463 blkoff = (group % desc_per_blk) * sizeof(struct ext2_block_group); 1464 1465 debug("ext4fs read %d group descriptor (blkno %ld blkoff %u)\n", 1466 group, blkno, blkoff); 1467 1468 return ext4fs_devread((lbaint_t)blkno << 1469 (LOG2_BLOCK_SIZE(data) - log2blksz), 1470 blkoff, sizeof(struct ext2_block_group), 1471 (char *)blkgrp); 1472 } 1473 1474 int ext4fs_read_inode(struct ext2_data *data, int ino, struct ext2_inode *inode) 1475 { 1476 struct ext2_block_group blkgrp; 1477 struct ext2_sblock *sblock = &data->sblock; 1478 struct ext_filesystem *fs = get_fs(); 1479 int log2blksz = get_fs()->dev_desc->log2blksz; 1480 int inodes_per_block, status; 1481 long int blkno; 1482 unsigned int blkoff; 1483 1484 /* It is easier to calculate if the first inode is 0. */ 1485 ino--; 1486 status = ext4fs_blockgroup(data, ino / __le32_to_cpu 1487 (sblock->inodes_per_group), &blkgrp); 1488 if (status == 0) 1489 return 0; 1490 1491 inodes_per_block = EXT2_BLOCK_SIZE(data) / fs->inodesz; 1492 blkno = __le32_to_cpu(blkgrp.inode_table_id) + 1493 (ino % __le32_to_cpu(sblock->inodes_per_group)) / inodes_per_block; 1494 blkoff = (ino % inodes_per_block) * fs->inodesz; 1495 /* Read the inode. */ 1496 status = ext4fs_devread((lbaint_t)blkno << (LOG2_BLOCK_SIZE(data) - 1497 log2blksz), blkoff, 1498 sizeof(struct ext2_inode), (char *)inode); 1499 if (status == 0) 1500 return 0; 1501 1502 return 1; 1503 } 1504 1505 long int read_allocated_block(struct ext2_inode *inode, int fileblock) 1506 { 1507 long int blknr; 1508 int blksz; 1509 int log2_blksz; 1510 int status; 1511 long int rblock; 1512 long int perblock_parent; 1513 long int perblock_child; 1514 unsigned long long start; 1515 /* get the blocksize of the filesystem */ 1516 blksz = EXT2_BLOCK_SIZE(ext4fs_root); 1517 log2_blksz = LOG2_BLOCK_SIZE(ext4fs_root) 1518 - get_fs()->dev_desc->log2blksz; 1519 1520 if (le32_to_cpu(inode->flags) & EXT4_EXTENTS_FL) { 1521 char *buf = zalloc(blksz); 1522 if (!buf) 1523 return -ENOMEM; 1524 struct ext4_extent_header *ext_block; 1525 struct ext4_extent *extent; 1526 int i = -1; 1527 ext_block = 1528 ext4fs_get_extent_block(ext4fs_root, buf, 1529 (struct ext4_extent_header *) 1530 inode->b.blocks.dir_blocks, 1531 fileblock, log2_blksz); 1532 if (!ext_block) { 1533 printf("invalid extent block\n"); 1534 free(buf); 1535 return -EINVAL; 1536 } 1537 1538 extent = (struct ext4_extent *)(ext_block + 1); 1539 1540 do { 1541 i++; 1542 if (i >= le16_to_cpu(ext_block->eh_entries)) 1543 break; 1544 } while (fileblock >= le32_to_cpu(extent[i].ee_block)); 1545 if (--i >= 0) { 1546 fileblock -= le32_to_cpu(extent[i].ee_block); 1547 if (fileblock >= le16_to_cpu(extent[i].ee_len)) { 1548 free(buf); 1549 return 0; 1550 } 1551 1552 start = le16_to_cpu(extent[i].ee_start_hi); 1553 start = (start << 32) + 1554 le32_to_cpu(extent[i].ee_start_lo); 1555 free(buf); 1556 return fileblock + start; 1557 } 1558 1559 printf("Extent Error\n"); 1560 free(buf); 1561 return -1; 1562 } 1563 1564 /* Direct blocks. */ 1565 if (fileblock < INDIRECT_BLOCKS) 1566 blknr = __le32_to_cpu(inode->b.blocks.dir_blocks[fileblock]); 1567 1568 /* Indirect. */ 1569 else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4))) { 1570 if (ext4fs_indir1_block == NULL) { 1571 ext4fs_indir1_block = zalloc(blksz); 1572 if (ext4fs_indir1_block == NULL) { 1573 printf("** SI ext2fs read block (indir 1)" 1574 "malloc failed. **\n"); 1575 return -1; 1576 } 1577 ext4fs_indir1_size = blksz; 1578 ext4fs_indir1_blkno = -1; 1579 } 1580 if (blksz != ext4fs_indir1_size) { 1581 free(ext4fs_indir1_block); 1582 ext4fs_indir1_block = NULL; 1583 ext4fs_indir1_size = 0; 1584 ext4fs_indir1_blkno = -1; 1585 ext4fs_indir1_block = zalloc(blksz); 1586 if (ext4fs_indir1_block == NULL) { 1587 printf("** SI ext2fs read block (indir 1):" 1588 "malloc failed. **\n"); 1589 return -1; 1590 } 1591 ext4fs_indir1_size = blksz; 1592 } 1593 if ((__le32_to_cpu(inode->b.blocks.indir_block) << 1594 log2_blksz) != ext4fs_indir1_blkno) { 1595 status = 1596 ext4fs_devread((lbaint_t)__le32_to_cpu 1597 (inode->b.blocks. 1598 indir_block) << log2_blksz, 0, 1599 blksz, (char *)ext4fs_indir1_block); 1600 if (status == 0) { 1601 printf("** SI ext2fs read block (indir 1)" 1602 "failed. **\n"); 1603 return 0; 1604 } 1605 ext4fs_indir1_blkno = 1606 __le32_to_cpu(inode->b.blocks. 1607 indir_block) << log2_blksz; 1608 } 1609 blknr = __le32_to_cpu(ext4fs_indir1_block 1610 [fileblock - INDIRECT_BLOCKS]); 1611 } 1612 /* Double indirect. */ 1613 else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4 * 1614 (blksz / 4 + 1)))) { 1615 1616 long int perblock = blksz / 4; 1617 long int rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4); 1618 1619 if (ext4fs_indir1_block == NULL) { 1620 ext4fs_indir1_block = zalloc(blksz); 1621 if (ext4fs_indir1_block == NULL) { 1622 printf("** DI ext2fs read block (indir 2 1)" 1623 "malloc failed. **\n"); 1624 return -1; 1625 } 1626 ext4fs_indir1_size = blksz; 1627 ext4fs_indir1_blkno = -1; 1628 } 1629 if (blksz != ext4fs_indir1_size) { 1630 free(ext4fs_indir1_block); 1631 ext4fs_indir1_block = NULL; 1632 ext4fs_indir1_size = 0; 1633 ext4fs_indir1_blkno = -1; 1634 ext4fs_indir1_block = zalloc(blksz); 1635 if (ext4fs_indir1_block == NULL) { 1636 printf("** DI ext2fs read block (indir 2 1)" 1637 "malloc failed. **\n"); 1638 return -1; 1639 } 1640 ext4fs_indir1_size = blksz; 1641 } 1642 if ((__le32_to_cpu(inode->b.blocks.double_indir_block) << 1643 log2_blksz) != ext4fs_indir1_blkno) { 1644 status = 1645 ext4fs_devread((lbaint_t)__le32_to_cpu 1646 (inode->b.blocks. 1647 double_indir_block) << log2_blksz, 1648 0, blksz, 1649 (char *)ext4fs_indir1_block); 1650 if (status == 0) { 1651 printf("** DI ext2fs read block (indir 2 1)" 1652 "failed. **\n"); 1653 return -1; 1654 } 1655 ext4fs_indir1_blkno = 1656 __le32_to_cpu(inode->b.blocks.double_indir_block) << 1657 log2_blksz; 1658 } 1659 1660 if (ext4fs_indir2_block == NULL) { 1661 ext4fs_indir2_block = zalloc(blksz); 1662 if (ext4fs_indir2_block == NULL) { 1663 printf("** DI ext2fs read block (indir 2 2)" 1664 "malloc failed. **\n"); 1665 return -1; 1666 } 1667 ext4fs_indir2_size = blksz; 1668 ext4fs_indir2_blkno = -1; 1669 } 1670 if (blksz != ext4fs_indir2_size) { 1671 free(ext4fs_indir2_block); 1672 ext4fs_indir2_block = NULL; 1673 ext4fs_indir2_size = 0; 1674 ext4fs_indir2_blkno = -1; 1675 ext4fs_indir2_block = zalloc(blksz); 1676 if (ext4fs_indir2_block == NULL) { 1677 printf("** DI ext2fs read block (indir 2 2)" 1678 "malloc failed. **\n"); 1679 return -1; 1680 } 1681 ext4fs_indir2_size = blksz; 1682 } 1683 if ((__le32_to_cpu(ext4fs_indir1_block[rblock / perblock]) << 1684 log2_blksz) != ext4fs_indir2_blkno) { 1685 status = ext4fs_devread((lbaint_t)__le32_to_cpu 1686 (ext4fs_indir1_block 1687 [rblock / 1688 perblock]) << log2_blksz, 0, 1689 blksz, 1690 (char *)ext4fs_indir2_block); 1691 if (status == 0) { 1692 printf("** DI ext2fs read block (indir 2 2)" 1693 "failed. **\n"); 1694 return -1; 1695 } 1696 ext4fs_indir2_blkno = 1697 __le32_to_cpu(ext4fs_indir1_block[rblock 1698 / 1699 perblock]) << 1700 log2_blksz; 1701 } 1702 blknr = __le32_to_cpu(ext4fs_indir2_block[rblock % perblock]); 1703 } 1704 /* Tripple indirect. */ 1705 else { 1706 rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4 + 1707 (blksz / 4 * blksz / 4)); 1708 perblock_child = blksz / 4; 1709 perblock_parent = ((blksz / 4) * (blksz / 4)); 1710 1711 if (ext4fs_indir1_block == NULL) { 1712 ext4fs_indir1_block = zalloc(blksz); 1713 if (ext4fs_indir1_block == NULL) { 1714 printf("** TI ext2fs read block (indir 2 1)" 1715 "malloc failed. **\n"); 1716 return -1; 1717 } 1718 ext4fs_indir1_size = blksz; 1719 ext4fs_indir1_blkno = -1; 1720 } 1721 if (blksz != ext4fs_indir1_size) { 1722 free(ext4fs_indir1_block); 1723 ext4fs_indir1_block = NULL; 1724 ext4fs_indir1_size = 0; 1725 ext4fs_indir1_blkno = -1; 1726 ext4fs_indir1_block = zalloc(blksz); 1727 if (ext4fs_indir1_block == NULL) { 1728 printf("** TI ext2fs read block (indir 2 1)" 1729 "malloc failed. **\n"); 1730 return -1; 1731 } 1732 ext4fs_indir1_size = blksz; 1733 } 1734 if ((__le32_to_cpu(inode->b.blocks.triple_indir_block) << 1735 log2_blksz) != ext4fs_indir1_blkno) { 1736 status = ext4fs_devread 1737 ((lbaint_t) 1738 __le32_to_cpu(inode->b.blocks.triple_indir_block) 1739 << log2_blksz, 0, blksz, 1740 (char *)ext4fs_indir1_block); 1741 if (status == 0) { 1742 printf("** TI ext2fs read block (indir 2 1)" 1743 "failed. **\n"); 1744 return -1; 1745 } 1746 ext4fs_indir1_blkno = 1747 __le32_to_cpu(inode->b.blocks.triple_indir_block) << 1748 log2_blksz; 1749 } 1750 1751 if (ext4fs_indir2_block == NULL) { 1752 ext4fs_indir2_block = zalloc(blksz); 1753 if (ext4fs_indir2_block == NULL) { 1754 printf("** TI ext2fs read block (indir 2 2)" 1755 "malloc failed. **\n"); 1756 return -1; 1757 } 1758 ext4fs_indir2_size = blksz; 1759 ext4fs_indir2_blkno = -1; 1760 } 1761 if (blksz != ext4fs_indir2_size) { 1762 free(ext4fs_indir2_block); 1763 ext4fs_indir2_block = NULL; 1764 ext4fs_indir2_size = 0; 1765 ext4fs_indir2_blkno = -1; 1766 ext4fs_indir2_block = zalloc(blksz); 1767 if (ext4fs_indir2_block == NULL) { 1768 printf("** TI ext2fs read block (indir 2 2)" 1769 "malloc failed. **\n"); 1770 return -1; 1771 } 1772 ext4fs_indir2_size = blksz; 1773 } 1774 if ((__le32_to_cpu(ext4fs_indir1_block[rblock / 1775 perblock_parent]) << 1776 log2_blksz) 1777 != ext4fs_indir2_blkno) { 1778 status = ext4fs_devread((lbaint_t)__le32_to_cpu 1779 (ext4fs_indir1_block 1780 [rblock / 1781 perblock_parent]) << 1782 log2_blksz, 0, blksz, 1783 (char *)ext4fs_indir2_block); 1784 if (status == 0) { 1785 printf("** TI ext2fs read block (indir 2 2)" 1786 "failed. **\n"); 1787 return -1; 1788 } 1789 ext4fs_indir2_blkno = 1790 __le32_to_cpu(ext4fs_indir1_block[rblock / 1791 perblock_parent]) 1792 << log2_blksz; 1793 } 1794 1795 if (ext4fs_indir3_block == NULL) { 1796 ext4fs_indir3_block = zalloc(blksz); 1797 if (ext4fs_indir3_block == NULL) { 1798 printf("** TI ext2fs read block (indir 2 2)" 1799 "malloc failed. **\n"); 1800 return -1; 1801 } 1802 ext4fs_indir3_size = blksz; 1803 ext4fs_indir3_blkno = -1; 1804 } 1805 if (blksz != ext4fs_indir3_size) { 1806 free(ext4fs_indir3_block); 1807 ext4fs_indir3_block = NULL; 1808 ext4fs_indir3_size = 0; 1809 ext4fs_indir3_blkno = -1; 1810 ext4fs_indir3_block = zalloc(blksz); 1811 if (ext4fs_indir3_block == NULL) { 1812 printf("** TI ext2fs read block (indir 2 2)" 1813 "malloc failed. **\n"); 1814 return -1; 1815 } 1816 ext4fs_indir3_size = blksz; 1817 } 1818 if ((__le32_to_cpu(ext4fs_indir2_block[rblock 1819 / 1820 perblock_child]) << 1821 log2_blksz) != ext4fs_indir3_blkno) { 1822 status = 1823 ext4fs_devread((lbaint_t)__le32_to_cpu 1824 (ext4fs_indir2_block 1825 [(rblock / perblock_child) 1826 % (blksz / 4)]) << log2_blksz, 0, 1827 blksz, (char *)ext4fs_indir3_block); 1828 if (status == 0) { 1829 printf("** TI ext2fs read block (indir 2 2)" 1830 "failed. **\n"); 1831 return -1; 1832 } 1833 ext4fs_indir3_blkno = 1834 __le32_to_cpu(ext4fs_indir2_block[(rblock / 1835 perblock_child) % 1836 (blksz / 1837 4)]) << 1838 log2_blksz; 1839 } 1840 1841 blknr = __le32_to_cpu(ext4fs_indir3_block 1842 [rblock % perblock_child]); 1843 } 1844 debug("read_allocated_block %ld\n", blknr); 1845 1846 return blknr; 1847 } 1848 1849 /** 1850 * ext4fs_reinit_global() - Reinitialize values of ext4 write implementation's 1851 * global pointers 1852 * 1853 * This function assures that for a file with the same name but different size 1854 * the sequential store on the ext4 filesystem will be correct. 1855 * 1856 * In this function the global data, responsible for internal representation 1857 * of the ext4 data are initialized to the reset state. Without this, during 1858 * replacement of the smaller file with the bigger truncation of new file was 1859 * performed. 1860 */ 1861 void ext4fs_reinit_global(void) 1862 { 1863 if (ext4fs_indir1_block != NULL) { 1864 free(ext4fs_indir1_block); 1865 ext4fs_indir1_block = NULL; 1866 ext4fs_indir1_size = 0; 1867 ext4fs_indir1_blkno = -1; 1868 } 1869 if (ext4fs_indir2_block != NULL) { 1870 free(ext4fs_indir2_block); 1871 ext4fs_indir2_block = NULL; 1872 ext4fs_indir2_size = 0; 1873 ext4fs_indir2_blkno = -1; 1874 } 1875 if (ext4fs_indir3_block != NULL) { 1876 free(ext4fs_indir3_block); 1877 ext4fs_indir3_block = NULL; 1878 ext4fs_indir3_size = 0; 1879 ext4fs_indir3_blkno = -1; 1880 } 1881 } 1882 void ext4fs_close(void) 1883 { 1884 if ((ext4fs_file != NULL) && (ext4fs_root != NULL)) { 1885 ext4fs_free_node(ext4fs_file, &ext4fs_root->diropen); 1886 ext4fs_file = NULL; 1887 } 1888 if (ext4fs_root != NULL) { 1889 free(ext4fs_root); 1890 ext4fs_root = NULL; 1891 } 1892 1893 ext4fs_reinit_global(); 1894 } 1895 1896 int ext4fs_iterate_dir(struct ext2fs_node *dir, char *name, 1897 struct ext2fs_node **fnode, int *ftype) 1898 { 1899 unsigned int fpos = 0; 1900 int status; 1901 loff_t actread; 1902 struct ext2fs_node *diro = (struct ext2fs_node *) dir; 1903 1904 #ifdef DEBUG 1905 if (name != NULL) 1906 printf("Iterate dir %s\n", name); 1907 #endif /* of DEBUG */ 1908 if (!diro->inode_read) { 1909 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode); 1910 if (status == 0) 1911 return 0; 1912 } 1913 /* Search the file. */ 1914 while (fpos < __le32_to_cpu(diro->inode.size)) { 1915 struct ext2_dirent dirent; 1916 1917 status = ext4fs_read_file(diro, fpos, 1918 sizeof(struct ext2_dirent), 1919 (char *)&dirent, &actread); 1920 if (status < 0) 1921 return 0; 1922 1923 if (dirent.namelen != 0) { 1924 char filename[dirent.namelen + 1]; 1925 struct ext2fs_node *fdiro; 1926 int type = FILETYPE_UNKNOWN; 1927 1928 status = ext4fs_read_file(diro, 1929 fpos + 1930 sizeof(struct ext2_dirent), 1931 dirent.namelen, filename, 1932 &actread); 1933 if (status < 0) 1934 return 0; 1935 1936 fdiro = zalloc(sizeof(struct ext2fs_node)); 1937 if (!fdiro) 1938 return 0; 1939 1940 fdiro->data = diro->data; 1941 fdiro->ino = __le32_to_cpu(dirent.inode); 1942 1943 filename[dirent.namelen] = '\0'; 1944 1945 if (dirent.filetype != FILETYPE_UNKNOWN) { 1946 fdiro->inode_read = 0; 1947 1948 if (dirent.filetype == FILETYPE_DIRECTORY) 1949 type = FILETYPE_DIRECTORY; 1950 else if (dirent.filetype == FILETYPE_SYMLINK) 1951 type = FILETYPE_SYMLINK; 1952 else if (dirent.filetype == FILETYPE_REG) 1953 type = FILETYPE_REG; 1954 } else { 1955 status = ext4fs_read_inode(diro->data, 1956 __le32_to_cpu 1957 (dirent.inode), 1958 &fdiro->inode); 1959 if (status == 0) { 1960 free(fdiro); 1961 return 0; 1962 } 1963 fdiro->inode_read = 1; 1964 1965 if ((__le16_to_cpu(fdiro->inode.mode) & 1966 FILETYPE_INO_MASK) == 1967 FILETYPE_INO_DIRECTORY) { 1968 type = FILETYPE_DIRECTORY; 1969 } else if ((__le16_to_cpu(fdiro->inode.mode) 1970 & FILETYPE_INO_MASK) == 1971 FILETYPE_INO_SYMLINK) { 1972 type = FILETYPE_SYMLINK; 1973 } else if ((__le16_to_cpu(fdiro->inode.mode) 1974 & FILETYPE_INO_MASK) == 1975 FILETYPE_INO_REG) { 1976 type = FILETYPE_REG; 1977 } 1978 } 1979 #ifdef DEBUG 1980 printf("iterate >%s<\n", filename); 1981 #endif /* of DEBUG */ 1982 if ((name != NULL) && (fnode != NULL) 1983 && (ftype != NULL)) { 1984 if (strcmp(filename, name) == 0) { 1985 *ftype = type; 1986 *fnode = fdiro; 1987 return 1; 1988 } 1989 } else { 1990 if (fdiro->inode_read == 0) { 1991 status = ext4fs_read_inode(diro->data, 1992 __le32_to_cpu( 1993 dirent.inode), 1994 &fdiro->inode); 1995 if (status == 0) { 1996 free(fdiro); 1997 return 0; 1998 } 1999 fdiro->inode_read = 1; 2000 } 2001 switch (type) { 2002 case FILETYPE_DIRECTORY: 2003 printf("<DIR> "); 2004 break; 2005 case FILETYPE_SYMLINK: 2006 printf("<SYM> "); 2007 break; 2008 case FILETYPE_REG: 2009 printf(" "); 2010 break; 2011 default: 2012 printf("< ? > "); 2013 break; 2014 } 2015 printf("%10u %s\n", 2016 __le32_to_cpu(fdiro->inode.size), 2017 filename); 2018 } 2019 free(fdiro); 2020 } 2021 fpos += __le16_to_cpu(dirent.direntlen); 2022 } 2023 return 0; 2024 } 2025 2026 static char *ext4fs_read_symlink(struct ext2fs_node *node) 2027 { 2028 char *symlink; 2029 struct ext2fs_node *diro = node; 2030 int status; 2031 loff_t actread; 2032 2033 if (!diro->inode_read) { 2034 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode); 2035 if (status == 0) 2036 return 0; 2037 } 2038 symlink = zalloc(__le32_to_cpu(diro->inode.size) + 1); 2039 if (!symlink) 2040 return 0; 2041 2042 if (__le32_to_cpu(diro->inode.size) <= 60) { 2043 strncpy(symlink, diro->inode.b.symlink, 2044 __le32_to_cpu(diro->inode.size)); 2045 } else { 2046 status = ext4fs_read_file(diro, 0, 2047 __le32_to_cpu(diro->inode.size), 2048 symlink, &actread); 2049 if ((status < 0) || (actread == 0)) { 2050 free(symlink); 2051 return 0; 2052 } 2053 } 2054 symlink[__le32_to_cpu(diro->inode.size)] = '\0'; 2055 return symlink; 2056 } 2057 2058 static int ext4fs_find_file1(const char *currpath, 2059 struct ext2fs_node *currroot, 2060 struct ext2fs_node **currfound, int *foundtype) 2061 { 2062 char fpath[strlen(currpath) + 1]; 2063 char *name = fpath; 2064 char *next; 2065 int status; 2066 int type = FILETYPE_DIRECTORY; 2067 struct ext2fs_node *currnode = currroot; 2068 struct ext2fs_node *oldnode = currroot; 2069 2070 strncpy(fpath, currpath, strlen(currpath) + 1); 2071 2072 /* Remove all leading slashes. */ 2073 while (*name == '/') 2074 name++; 2075 2076 if (!*name) { 2077 *currfound = currnode; 2078 return 1; 2079 } 2080 2081 for (;;) { 2082 int found; 2083 2084 /* Extract the actual part from the pathname. */ 2085 next = strchr(name, '/'); 2086 if (next) { 2087 /* Remove all leading slashes. */ 2088 while (*next == '/') 2089 *(next++) = '\0'; 2090 } 2091 2092 if (type != FILETYPE_DIRECTORY) { 2093 ext4fs_free_node(currnode, currroot); 2094 return 0; 2095 } 2096 2097 oldnode = currnode; 2098 2099 /* Iterate over the directory. */ 2100 found = ext4fs_iterate_dir(currnode, name, &currnode, &type); 2101 if (found == 0) 2102 return 0; 2103 2104 if (found == -1) 2105 break; 2106 2107 /* Read in the symlink and follow it. */ 2108 if (type == FILETYPE_SYMLINK) { 2109 char *symlink; 2110 2111 /* Test if the symlink does not loop. */ 2112 if (++symlinknest == 8) { 2113 ext4fs_free_node(currnode, currroot); 2114 ext4fs_free_node(oldnode, currroot); 2115 return 0; 2116 } 2117 2118 symlink = ext4fs_read_symlink(currnode); 2119 ext4fs_free_node(currnode, currroot); 2120 2121 if (!symlink) { 2122 ext4fs_free_node(oldnode, currroot); 2123 return 0; 2124 } 2125 2126 debug("Got symlink >%s<\n", symlink); 2127 2128 if (symlink[0] == '/') { 2129 ext4fs_free_node(oldnode, currroot); 2130 oldnode = &ext4fs_root->diropen; 2131 } 2132 2133 /* Lookup the node the symlink points to. */ 2134 status = ext4fs_find_file1(symlink, oldnode, 2135 &currnode, &type); 2136 2137 free(symlink); 2138 2139 if (status == 0) { 2140 ext4fs_free_node(oldnode, currroot); 2141 return 0; 2142 } 2143 } 2144 2145 ext4fs_free_node(oldnode, currroot); 2146 2147 /* Found the node! */ 2148 if (!next || *next == '\0') { 2149 *currfound = currnode; 2150 *foundtype = type; 2151 return 1; 2152 } 2153 name = next; 2154 } 2155 return -1; 2156 } 2157 2158 int ext4fs_find_file(const char *path, struct ext2fs_node *rootnode, 2159 struct ext2fs_node **foundnode, int expecttype) 2160 { 2161 int status; 2162 int foundtype = FILETYPE_DIRECTORY; 2163 2164 symlinknest = 0; 2165 if (!path) 2166 return 0; 2167 2168 status = ext4fs_find_file1(path, rootnode, foundnode, &foundtype); 2169 if (status == 0) 2170 return 0; 2171 2172 /* Check if the node that was found was of the expected type. */ 2173 if ((expecttype == FILETYPE_REG) && (foundtype != expecttype)) 2174 return 0; 2175 else if ((expecttype == FILETYPE_DIRECTORY) 2176 && (foundtype != expecttype)) 2177 return 0; 2178 2179 return 1; 2180 } 2181 2182 int ext4fs_open(const char *filename, loff_t *len) 2183 { 2184 struct ext2fs_node *fdiro = NULL; 2185 int status; 2186 2187 if (ext4fs_root == NULL) 2188 return -1; 2189 2190 ext4fs_file = NULL; 2191 status = ext4fs_find_file(filename, &ext4fs_root->diropen, &fdiro, 2192 FILETYPE_REG); 2193 if (status == 0) 2194 goto fail; 2195 2196 if (!fdiro->inode_read) { 2197 status = ext4fs_read_inode(fdiro->data, fdiro->ino, 2198 &fdiro->inode); 2199 if (status == 0) 2200 goto fail; 2201 } 2202 *len = __le32_to_cpu(fdiro->inode.size); 2203 ext4fs_file = fdiro; 2204 2205 return 0; 2206 fail: 2207 ext4fs_free_node(fdiro, &ext4fs_root->diropen); 2208 2209 return -1; 2210 } 2211 2212 int ext4fs_mount(unsigned part_length) 2213 { 2214 struct ext2_data *data; 2215 int status; 2216 struct ext_filesystem *fs = get_fs(); 2217 data = zalloc(SUPERBLOCK_SIZE); 2218 if (!data) 2219 return 0; 2220 2221 /* Read the superblock. */ 2222 status = ext4_read_superblock((char *)&data->sblock); 2223 2224 if (status == 0) 2225 goto fail; 2226 2227 /* Make sure this is an ext2 filesystem. */ 2228 if (__le16_to_cpu(data->sblock.magic) != EXT2_MAGIC) 2229 goto fail; 2230 2231 if (__le32_to_cpu(data->sblock.revision_level == 0)) 2232 fs->inodesz = 128; 2233 else 2234 fs->inodesz = __le16_to_cpu(data->sblock.inode_size); 2235 2236 debug("EXT2 rev %d, inode_size %d\n", 2237 __le32_to_cpu(data->sblock.revision_level), fs->inodesz); 2238 2239 data->diropen.data = data; 2240 data->diropen.ino = 2; 2241 data->diropen.inode_read = 1; 2242 data->inode = &data->diropen.inode; 2243 2244 status = ext4fs_read_inode(data, 2, data->inode); 2245 if (status == 0) 2246 goto fail; 2247 2248 ext4fs_root = data; 2249 2250 return 1; 2251 fail: 2252 printf("Failed to mount ext2 filesystem...\n"); 2253 free(data); 2254 ext4fs_root = NULL; 2255 2256 return 0; 2257 } 2258