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, 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, 91 startblock, 1, sec_buf); 92 } 93 } else { 94 if (size >> log2blksz != 0) { 95 fs->dev_desc->block_write(fs->dev_desc, 96 startblock, 97 size >> log2blksz, 98 (unsigned long *)buf); 99 } else { 100 fs->dev_desc->block_read(fs->dev_desc, 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, 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 return; 1291 } 1292 ti_gp_buff = zalloc(fs->blksz); 1293 if (!ti_gp_buff) 1294 return; 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 fail1; 1325 } 1326 ti_child_buff = zalloc(fs->blksz); 1327 if (!ti_child_buff) 1328 goto fail1; 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 free(ti_cbuff_start_addr); 1345 goto fail1; 1346 } 1347 *ti_child_buff = actual_block_no; 1348 debug("TIAB %ld: %u\n", actual_block_no, 1349 *total_remaining_blocks); 1350 1351 ti_child_buff++; 1352 (*total_remaining_blocks)--; 1353 if (*total_remaining_blocks == 0) 1354 break; 1355 } 1356 /* write the child block */ 1357 put_ext4(((uint64_t) ((uint64_t)ti_child_blockno * 1358 (uint64_t)fs->blksz)), 1359 ti_cbuff_start_addr, fs->blksz); 1360 free(ti_cbuff_start_addr); 1361 1362 if (*total_remaining_blocks == 0) 1363 break; 1364 } 1365 /* write the parent block */ 1366 put_ext4(((uint64_t) ((uint64_t)ti_parent_blockno * (uint64_t)fs->blksz)), 1367 ti_pbuff_start_addr, fs->blksz); 1368 free(ti_pbuff_start_addr); 1369 1370 if (*total_remaining_blocks == 0) 1371 break; 1372 } 1373 /* write the grand parent block */ 1374 put_ext4(((uint64_t) ((uint64_t)ti_gp_blockno * (uint64_t)fs->blksz)), 1375 ti_gp_buff_start_addr, fs->blksz); 1376 file_inode->b.blocks.triple_indir_block = ti_gp_blockno; 1377 free(ti_gp_buff_start_addr); 1378 return; 1379 } 1380 fail1: 1381 free(ti_pbuff_start_addr); 1382 fail: 1383 free(ti_gp_buff_start_addr); 1384 } 1385 1386 void ext4fs_allocate_blocks(struct ext2_inode *file_inode, 1387 unsigned int total_remaining_blocks, 1388 unsigned int *total_no_of_block) 1389 { 1390 short i; 1391 long int direct_blockno; 1392 unsigned int no_blks_reqd = 0; 1393 1394 /* allocation of direct blocks */ 1395 for (i = 0; total_remaining_blocks && i < INDIRECT_BLOCKS; i++) { 1396 direct_blockno = ext4fs_get_new_blk_no(); 1397 if (direct_blockno == -1) { 1398 printf("no block left to assign\n"); 1399 return; 1400 } 1401 file_inode->b.blocks.dir_blocks[i] = direct_blockno; 1402 debug("DB %ld: %u\n", direct_blockno, total_remaining_blocks); 1403 1404 total_remaining_blocks--; 1405 } 1406 1407 alloc_single_indirect_block(file_inode, &total_remaining_blocks, 1408 &no_blks_reqd); 1409 alloc_double_indirect_block(file_inode, &total_remaining_blocks, 1410 &no_blks_reqd); 1411 alloc_triple_indirect_block(file_inode, &total_remaining_blocks, 1412 &no_blks_reqd); 1413 *total_no_of_block += no_blks_reqd; 1414 } 1415 1416 #endif 1417 1418 static struct ext4_extent_header *ext4fs_get_extent_block 1419 (struct ext2_data *data, char *buf, 1420 struct ext4_extent_header *ext_block, 1421 uint32_t fileblock, int log2_blksz) 1422 { 1423 struct ext4_extent_idx *index; 1424 unsigned long long block; 1425 int blksz = EXT2_BLOCK_SIZE(data); 1426 int i; 1427 1428 while (1) { 1429 index = (struct ext4_extent_idx *)(ext_block + 1); 1430 1431 if (le16_to_cpu(ext_block->eh_magic) != EXT4_EXT_MAGIC) 1432 return 0; 1433 1434 if (ext_block->eh_depth == 0) 1435 return ext_block; 1436 i = -1; 1437 do { 1438 i++; 1439 if (i >= le16_to_cpu(ext_block->eh_entries)) 1440 break; 1441 } while (fileblock >= le32_to_cpu(index[i].ei_block)); 1442 1443 if (--i < 0) 1444 return 0; 1445 1446 block = le16_to_cpu(index[i].ei_leaf_hi); 1447 block = (block << 32) + le32_to_cpu(index[i].ei_leaf_lo); 1448 1449 if (ext4fs_devread((lbaint_t)block << log2_blksz, 0, blksz, 1450 buf)) 1451 ext_block = (struct ext4_extent_header *)buf; 1452 else 1453 return 0; 1454 } 1455 } 1456 1457 static int ext4fs_blockgroup 1458 (struct ext2_data *data, int group, struct ext2_block_group *blkgrp) 1459 { 1460 long int blkno; 1461 unsigned int blkoff, desc_per_blk; 1462 int log2blksz = get_fs()->dev_desc->log2blksz; 1463 1464 desc_per_blk = EXT2_BLOCK_SIZE(data) / sizeof(struct ext2_block_group); 1465 1466 blkno = __le32_to_cpu(data->sblock.first_data_block) + 1 + 1467 group / desc_per_blk; 1468 blkoff = (group % desc_per_blk) * sizeof(struct ext2_block_group); 1469 1470 debug("ext4fs read %d group descriptor (blkno %ld blkoff %u)\n", 1471 group, blkno, blkoff); 1472 1473 return ext4fs_devread((lbaint_t)blkno << 1474 (LOG2_BLOCK_SIZE(data) - log2blksz), 1475 blkoff, sizeof(struct ext2_block_group), 1476 (char *)blkgrp); 1477 } 1478 1479 int ext4fs_read_inode(struct ext2_data *data, int ino, struct ext2_inode *inode) 1480 { 1481 struct ext2_block_group blkgrp; 1482 struct ext2_sblock *sblock = &data->sblock; 1483 struct ext_filesystem *fs = get_fs(); 1484 int log2blksz = get_fs()->dev_desc->log2blksz; 1485 int inodes_per_block, status; 1486 long int blkno; 1487 unsigned int blkoff; 1488 1489 /* It is easier to calculate if the first inode is 0. */ 1490 ino--; 1491 status = ext4fs_blockgroup(data, ino / __le32_to_cpu 1492 (sblock->inodes_per_group), &blkgrp); 1493 if (status == 0) 1494 return 0; 1495 1496 inodes_per_block = EXT2_BLOCK_SIZE(data) / fs->inodesz; 1497 blkno = __le32_to_cpu(blkgrp.inode_table_id) + 1498 (ino % __le32_to_cpu(sblock->inodes_per_group)) / inodes_per_block; 1499 blkoff = (ino % inodes_per_block) * fs->inodesz; 1500 /* Read the inode. */ 1501 status = ext4fs_devread((lbaint_t)blkno << (LOG2_BLOCK_SIZE(data) - 1502 log2blksz), blkoff, 1503 sizeof(struct ext2_inode), (char *)inode); 1504 if (status == 0) 1505 return 0; 1506 1507 return 1; 1508 } 1509 1510 long int read_allocated_block(struct ext2_inode *inode, int fileblock) 1511 { 1512 long int blknr; 1513 int blksz; 1514 int log2_blksz; 1515 int status; 1516 long int rblock; 1517 long int perblock_parent; 1518 long int perblock_child; 1519 unsigned long long start; 1520 /* get the blocksize of the filesystem */ 1521 blksz = EXT2_BLOCK_SIZE(ext4fs_root); 1522 log2_blksz = LOG2_BLOCK_SIZE(ext4fs_root) 1523 - get_fs()->dev_desc->log2blksz; 1524 1525 if (le32_to_cpu(inode->flags) & EXT4_EXTENTS_FL) { 1526 char *buf = zalloc(blksz); 1527 if (!buf) 1528 return -ENOMEM; 1529 struct ext4_extent_header *ext_block; 1530 struct ext4_extent *extent; 1531 int i = -1; 1532 ext_block = 1533 ext4fs_get_extent_block(ext4fs_root, buf, 1534 (struct ext4_extent_header *) 1535 inode->b.blocks.dir_blocks, 1536 fileblock, log2_blksz); 1537 if (!ext_block) { 1538 printf("invalid extent block\n"); 1539 free(buf); 1540 return -EINVAL; 1541 } 1542 1543 extent = (struct ext4_extent *)(ext_block + 1); 1544 1545 do { 1546 i++; 1547 if (i >= le16_to_cpu(ext_block->eh_entries)) 1548 break; 1549 } while (fileblock >= le32_to_cpu(extent[i].ee_block)); 1550 if (--i >= 0) { 1551 fileblock -= le32_to_cpu(extent[i].ee_block); 1552 if (fileblock >= le16_to_cpu(extent[i].ee_len)) { 1553 free(buf); 1554 return 0; 1555 } 1556 1557 start = le16_to_cpu(extent[i].ee_start_hi); 1558 start = (start << 32) + 1559 le32_to_cpu(extent[i].ee_start_lo); 1560 free(buf); 1561 return fileblock + start; 1562 } 1563 1564 printf("Extent Error\n"); 1565 free(buf); 1566 return -1; 1567 } 1568 1569 /* Direct blocks. */ 1570 if (fileblock < INDIRECT_BLOCKS) 1571 blknr = __le32_to_cpu(inode->b.blocks.dir_blocks[fileblock]); 1572 1573 /* Indirect. */ 1574 else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4))) { 1575 if (ext4fs_indir1_block == NULL) { 1576 ext4fs_indir1_block = zalloc(blksz); 1577 if (ext4fs_indir1_block == NULL) { 1578 printf("** SI ext2fs read block (indir 1)" 1579 "malloc failed. **\n"); 1580 return -1; 1581 } 1582 ext4fs_indir1_size = blksz; 1583 ext4fs_indir1_blkno = -1; 1584 } 1585 if (blksz != ext4fs_indir1_size) { 1586 free(ext4fs_indir1_block); 1587 ext4fs_indir1_block = NULL; 1588 ext4fs_indir1_size = 0; 1589 ext4fs_indir1_blkno = -1; 1590 ext4fs_indir1_block = zalloc(blksz); 1591 if (ext4fs_indir1_block == NULL) { 1592 printf("** SI ext2fs read block (indir 1):" 1593 "malloc failed. **\n"); 1594 return -1; 1595 } 1596 ext4fs_indir1_size = blksz; 1597 } 1598 if ((__le32_to_cpu(inode->b.blocks.indir_block) << 1599 log2_blksz) != ext4fs_indir1_blkno) { 1600 status = 1601 ext4fs_devread((lbaint_t)__le32_to_cpu 1602 (inode->b.blocks. 1603 indir_block) << log2_blksz, 0, 1604 blksz, (char *)ext4fs_indir1_block); 1605 if (status == 0) { 1606 printf("** SI ext2fs read block (indir 1)" 1607 "failed. **\n"); 1608 return 0; 1609 } 1610 ext4fs_indir1_blkno = 1611 __le32_to_cpu(inode->b.blocks. 1612 indir_block) << log2_blksz; 1613 } 1614 blknr = __le32_to_cpu(ext4fs_indir1_block 1615 [fileblock - INDIRECT_BLOCKS]); 1616 } 1617 /* Double indirect. */ 1618 else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4 * 1619 (blksz / 4 + 1)))) { 1620 1621 long int perblock = blksz / 4; 1622 long int rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4); 1623 1624 if (ext4fs_indir1_block == NULL) { 1625 ext4fs_indir1_block = zalloc(blksz); 1626 if (ext4fs_indir1_block == NULL) { 1627 printf("** DI ext2fs read block (indir 2 1)" 1628 "malloc failed. **\n"); 1629 return -1; 1630 } 1631 ext4fs_indir1_size = blksz; 1632 ext4fs_indir1_blkno = -1; 1633 } 1634 if (blksz != ext4fs_indir1_size) { 1635 free(ext4fs_indir1_block); 1636 ext4fs_indir1_block = NULL; 1637 ext4fs_indir1_size = 0; 1638 ext4fs_indir1_blkno = -1; 1639 ext4fs_indir1_block = zalloc(blksz); 1640 if (ext4fs_indir1_block == NULL) { 1641 printf("** DI ext2fs read block (indir 2 1)" 1642 "malloc failed. **\n"); 1643 return -1; 1644 } 1645 ext4fs_indir1_size = blksz; 1646 } 1647 if ((__le32_to_cpu(inode->b.blocks.double_indir_block) << 1648 log2_blksz) != ext4fs_indir1_blkno) { 1649 status = 1650 ext4fs_devread((lbaint_t)__le32_to_cpu 1651 (inode->b.blocks. 1652 double_indir_block) << log2_blksz, 1653 0, blksz, 1654 (char *)ext4fs_indir1_block); 1655 if (status == 0) { 1656 printf("** DI ext2fs read block (indir 2 1)" 1657 "failed. **\n"); 1658 return -1; 1659 } 1660 ext4fs_indir1_blkno = 1661 __le32_to_cpu(inode->b.blocks.double_indir_block) << 1662 log2_blksz; 1663 } 1664 1665 if (ext4fs_indir2_block == NULL) { 1666 ext4fs_indir2_block = zalloc(blksz); 1667 if (ext4fs_indir2_block == NULL) { 1668 printf("** DI ext2fs read block (indir 2 2)" 1669 "malloc failed. **\n"); 1670 return -1; 1671 } 1672 ext4fs_indir2_size = blksz; 1673 ext4fs_indir2_blkno = -1; 1674 } 1675 if (blksz != ext4fs_indir2_size) { 1676 free(ext4fs_indir2_block); 1677 ext4fs_indir2_block = NULL; 1678 ext4fs_indir2_size = 0; 1679 ext4fs_indir2_blkno = -1; 1680 ext4fs_indir2_block = zalloc(blksz); 1681 if (ext4fs_indir2_block == NULL) { 1682 printf("** DI ext2fs read block (indir 2 2)" 1683 "malloc failed. **\n"); 1684 return -1; 1685 } 1686 ext4fs_indir2_size = blksz; 1687 } 1688 if ((__le32_to_cpu(ext4fs_indir1_block[rblock / perblock]) << 1689 log2_blksz) != ext4fs_indir2_blkno) { 1690 status = ext4fs_devread((lbaint_t)__le32_to_cpu 1691 (ext4fs_indir1_block 1692 [rblock / 1693 perblock]) << log2_blksz, 0, 1694 blksz, 1695 (char *)ext4fs_indir2_block); 1696 if (status == 0) { 1697 printf("** DI ext2fs read block (indir 2 2)" 1698 "failed. **\n"); 1699 return -1; 1700 } 1701 ext4fs_indir2_blkno = 1702 __le32_to_cpu(ext4fs_indir1_block[rblock 1703 / 1704 perblock]) << 1705 log2_blksz; 1706 } 1707 blknr = __le32_to_cpu(ext4fs_indir2_block[rblock % perblock]); 1708 } 1709 /* Tripple indirect. */ 1710 else { 1711 rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4 + 1712 (blksz / 4 * blksz / 4)); 1713 perblock_child = blksz / 4; 1714 perblock_parent = ((blksz / 4) * (blksz / 4)); 1715 1716 if (ext4fs_indir1_block == NULL) { 1717 ext4fs_indir1_block = zalloc(blksz); 1718 if (ext4fs_indir1_block == NULL) { 1719 printf("** TI ext2fs read block (indir 2 1)" 1720 "malloc failed. **\n"); 1721 return -1; 1722 } 1723 ext4fs_indir1_size = blksz; 1724 ext4fs_indir1_blkno = -1; 1725 } 1726 if (blksz != ext4fs_indir1_size) { 1727 free(ext4fs_indir1_block); 1728 ext4fs_indir1_block = NULL; 1729 ext4fs_indir1_size = 0; 1730 ext4fs_indir1_blkno = -1; 1731 ext4fs_indir1_block = zalloc(blksz); 1732 if (ext4fs_indir1_block == NULL) { 1733 printf("** TI ext2fs read block (indir 2 1)" 1734 "malloc failed. **\n"); 1735 return -1; 1736 } 1737 ext4fs_indir1_size = blksz; 1738 } 1739 if ((__le32_to_cpu(inode->b.blocks.triple_indir_block) << 1740 log2_blksz) != ext4fs_indir1_blkno) { 1741 status = ext4fs_devread 1742 ((lbaint_t) 1743 __le32_to_cpu(inode->b.blocks.triple_indir_block) 1744 << log2_blksz, 0, blksz, 1745 (char *)ext4fs_indir1_block); 1746 if (status == 0) { 1747 printf("** TI ext2fs read block (indir 2 1)" 1748 "failed. **\n"); 1749 return -1; 1750 } 1751 ext4fs_indir1_blkno = 1752 __le32_to_cpu(inode->b.blocks.triple_indir_block) << 1753 log2_blksz; 1754 } 1755 1756 if (ext4fs_indir2_block == NULL) { 1757 ext4fs_indir2_block = zalloc(blksz); 1758 if (ext4fs_indir2_block == NULL) { 1759 printf("** TI ext2fs read block (indir 2 2)" 1760 "malloc failed. **\n"); 1761 return -1; 1762 } 1763 ext4fs_indir2_size = blksz; 1764 ext4fs_indir2_blkno = -1; 1765 } 1766 if (blksz != ext4fs_indir2_size) { 1767 free(ext4fs_indir2_block); 1768 ext4fs_indir2_block = NULL; 1769 ext4fs_indir2_size = 0; 1770 ext4fs_indir2_blkno = -1; 1771 ext4fs_indir2_block = zalloc(blksz); 1772 if (ext4fs_indir2_block == NULL) { 1773 printf("** TI ext2fs read block (indir 2 2)" 1774 "malloc failed. **\n"); 1775 return -1; 1776 } 1777 ext4fs_indir2_size = blksz; 1778 } 1779 if ((__le32_to_cpu(ext4fs_indir1_block[rblock / 1780 perblock_parent]) << 1781 log2_blksz) 1782 != ext4fs_indir2_blkno) { 1783 status = ext4fs_devread((lbaint_t)__le32_to_cpu 1784 (ext4fs_indir1_block 1785 [rblock / 1786 perblock_parent]) << 1787 log2_blksz, 0, blksz, 1788 (char *)ext4fs_indir2_block); 1789 if (status == 0) { 1790 printf("** TI ext2fs read block (indir 2 2)" 1791 "failed. **\n"); 1792 return -1; 1793 } 1794 ext4fs_indir2_blkno = 1795 __le32_to_cpu(ext4fs_indir1_block[rblock / 1796 perblock_parent]) 1797 << log2_blksz; 1798 } 1799 1800 if (ext4fs_indir3_block == NULL) { 1801 ext4fs_indir3_block = zalloc(blksz); 1802 if (ext4fs_indir3_block == NULL) { 1803 printf("** TI ext2fs read block (indir 2 2)" 1804 "malloc failed. **\n"); 1805 return -1; 1806 } 1807 ext4fs_indir3_size = blksz; 1808 ext4fs_indir3_blkno = -1; 1809 } 1810 if (blksz != ext4fs_indir3_size) { 1811 free(ext4fs_indir3_block); 1812 ext4fs_indir3_block = NULL; 1813 ext4fs_indir3_size = 0; 1814 ext4fs_indir3_blkno = -1; 1815 ext4fs_indir3_block = zalloc(blksz); 1816 if (ext4fs_indir3_block == NULL) { 1817 printf("** TI ext2fs read block (indir 2 2)" 1818 "malloc failed. **\n"); 1819 return -1; 1820 } 1821 ext4fs_indir3_size = blksz; 1822 } 1823 if ((__le32_to_cpu(ext4fs_indir2_block[rblock 1824 / 1825 perblock_child]) << 1826 log2_blksz) != ext4fs_indir3_blkno) { 1827 status = 1828 ext4fs_devread((lbaint_t)__le32_to_cpu 1829 (ext4fs_indir2_block 1830 [(rblock / perblock_child) 1831 % (blksz / 4)]) << log2_blksz, 0, 1832 blksz, (char *)ext4fs_indir3_block); 1833 if (status == 0) { 1834 printf("** TI ext2fs read block (indir 2 2)" 1835 "failed. **\n"); 1836 return -1; 1837 } 1838 ext4fs_indir3_blkno = 1839 __le32_to_cpu(ext4fs_indir2_block[(rblock / 1840 perblock_child) % 1841 (blksz / 1842 4)]) << 1843 log2_blksz; 1844 } 1845 1846 blknr = __le32_to_cpu(ext4fs_indir3_block 1847 [rblock % perblock_child]); 1848 } 1849 debug("read_allocated_block %ld\n", blknr); 1850 1851 return blknr; 1852 } 1853 1854 /** 1855 * ext4fs_reinit_global() - Reinitialize values of ext4 write implementation's 1856 * global pointers 1857 * 1858 * This function assures that for a file with the same name but different size 1859 * the sequential store on the ext4 filesystem will be correct. 1860 * 1861 * In this function the global data, responsible for internal representation 1862 * of the ext4 data are initialized to the reset state. Without this, during 1863 * replacement of the smaller file with the bigger truncation of new file was 1864 * performed. 1865 */ 1866 void ext4fs_reinit_global(void) 1867 { 1868 if (ext4fs_indir1_block != NULL) { 1869 free(ext4fs_indir1_block); 1870 ext4fs_indir1_block = NULL; 1871 ext4fs_indir1_size = 0; 1872 ext4fs_indir1_blkno = -1; 1873 } 1874 if (ext4fs_indir2_block != NULL) { 1875 free(ext4fs_indir2_block); 1876 ext4fs_indir2_block = NULL; 1877 ext4fs_indir2_size = 0; 1878 ext4fs_indir2_blkno = -1; 1879 } 1880 if (ext4fs_indir3_block != NULL) { 1881 free(ext4fs_indir3_block); 1882 ext4fs_indir3_block = NULL; 1883 ext4fs_indir3_size = 0; 1884 ext4fs_indir3_blkno = -1; 1885 } 1886 } 1887 void ext4fs_close(void) 1888 { 1889 if ((ext4fs_file != NULL) && (ext4fs_root != NULL)) { 1890 ext4fs_free_node(ext4fs_file, &ext4fs_root->diropen); 1891 ext4fs_file = NULL; 1892 } 1893 if (ext4fs_root != NULL) { 1894 free(ext4fs_root); 1895 ext4fs_root = NULL; 1896 } 1897 1898 ext4fs_reinit_global(); 1899 } 1900 1901 int ext4fs_iterate_dir(struct ext2fs_node *dir, char *name, 1902 struct ext2fs_node **fnode, int *ftype) 1903 { 1904 unsigned int fpos = 0; 1905 int status; 1906 loff_t actread; 1907 struct ext2fs_node *diro = (struct ext2fs_node *) dir; 1908 1909 #ifdef DEBUG 1910 if (name != NULL) 1911 printf("Iterate dir %s\n", name); 1912 #endif /* of DEBUG */ 1913 if (!diro->inode_read) { 1914 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode); 1915 if (status == 0) 1916 return 0; 1917 } 1918 /* Search the file. */ 1919 while (fpos < __le32_to_cpu(diro->inode.size)) { 1920 struct ext2_dirent dirent; 1921 1922 status = ext4fs_read_file(diro, fpos, 1923 sizeof(struct ext2_dirent), 1924 (char *)&dirent, &actread); 1925 if (status < 0) 1926 return 0; 1927 1928 if (dirent.direntlen == 0) { 1929 printf("Failed to iterate over directory %s\n", name); 1930 return 0; 1931 } 1932 1933 if (dirent.namelen != 0) { 1934 char filename[dirent.namelen + 1]; 1935 struct ext2fs_node *fdiro; 1936 int type = FILETYPE_UNKNOWN; 1937 1938 status = ext4fs_read_file(diro, 1939 fpos + 1940 sizeof(struct ext2_dirent), 1941 dirent.namelen, filename, 1942 &actread); 1943 if (status < 0) 1944 return 0; 1945 1946 fdiro = zalloc(sizeof(struct ext2fs_node)); 1947 if (!fdiro) 1948 return 0; 1949 1950 fdiro->data = diro->data; 1951 fdiro->ino = __le32_to_cpu(dirent.inode); 1952 1953 filename[dirent.namelen] = '\0'; 1954 1955 if (dirent.filetype != FILETYPE_UNKNOWN) { 1956 fdiro->inode_read = 0; 1957 1958 if (dirent.filetype == FILETYPE_DIRECTORY) 1959 type = FILETYPE_DIRECTORY; 1960 else if (dirent.filetype == FILETYPE_SYMLINK) 1961 type = FILETYPE_SYMLINK; 1962 else if (dirent.filetype == FILETYPE_REG) 1963 type = FILETYPE_REG; 1964 } else { 1965 status = ext4fs_read_inode(diro->data, 1966 __le32_to_cpu 1967 (dirent.inode), 1968 &fdiro->inode); 1969 if (status == 0) { 1970 free(fdiro); 1971 return 0; 1972 } 1973 fdiro->inode_read = 1; 1974 1975 if ((__le16_to_cpu(fdiro->inode.mode) & 1976 FILETYPE_INO_MASK) == 1977 FILETYPE_INO_DIRECTORY) { 1978 type = FILETYPE_DIRECTORY; 1979 } else if ((__le16_to_cpu(fdiro->inode.mode) 1980 & FILETYPE_INO_MASK) == 1981 FILETYPE_INO_SYMLINK) { 1982 type = FILETYPE_SYMLINK; 1983 } else if ((__le16_to_cpu(fdiro->inode.mode) 1984 & FILETYPE_INO_MASK) == 1985 FILETYPE_INO_REG) { 1986 type = FILETYPE_REG; 1987 } 1988 } 1989 #ifdef DEBUG 1990 printf("iterate >%s<\n", filename); 1991 #endif /* of DEBUG */ 1992 if ((name != NULL) && (fnode != NULL) 1993 && (ftype != NULL)) { 1994 if (strcmp(filename, name) == 0) { 1995 *ftype = type; 1996 *fnode = fdiro; 1997 return 1; 1998 } 1999 } else { 2000 if (fdiro->inode_read == 0) { 2001 status = ext4fs_read_inode(diro->data, 2002 __le32_to_cpu( 2003 dirent.inode), 2004 &fdiro->inode); 2005 if (status == 0) { 2006 free(fdiro); 2007 return 0; 2008 } 2009 fdiro->inode_read = 1; 2010 } 2011 switch (type) { 2012 case FILETYPE_DIRECTORY: 2013 printf("<DIR> "); 2014 break; 2015 case FILETYPE_SYMLINK: 2016 printf("<SYM> "); 2017 break; 2018 case FILETYPE_REG: 2019 printf(" "); 2020 break; 2021 default: 2022 printf("< ? > "); 2023 break; 2024 } 2025 printf("%10u %s\n", 2026 __le32_to_cpu(fdiro->inode.size), 2027 filename); 2028 } 2029 free(fdiro); 2030 } 2031 fpos += __le16_to_cpu(dirent.direntlen); 2032 } 2033 return 0; 2034 } 2035 2036 static char *ext4fs_read_symlink(struct ext2fs_node *node) 2037 { 2038 char *symlink; 2039 struct ext2fs_node *diro = node; 2040 int status; 2041 loff_t actread; 2042 2043 if (!diro->inode_read) { 2044 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode); 2045 if (status == 0) 2046 return 0; 2047 } 2048 symlink = zalloc(__le32_to_cpu(diro->inode.size) + 1); 2049 if (!symlink) 2050 return 0; 2051 2052 if (__le32_to_cpu(diro->inode.size) <= 60) { 2053 strncpy(symlink, diro->inode.b.symlink, 2054 __le32_to_cpu(diro->inode.size)); 2055 } else { 2056 status = ext4fs_read_file(diro, 0, 2057 __le32_to_cpu(diro->inode.size), 2058 symlink, &actread); 2059 if ((status < 0) || (actread == 0)) { 2060 free(symlink); 2061 return 0; 2062 } 2063 } 2064 symlink[__le32_to_cpu(diro->inode.size)] = '\0'; 2065 return symlink; 2066 } 2067 2068 static int ext4fs_find_file1(const char *currpath, 2069 struct ext2fs_node *currroot, 2070 struct ext2fs_node **currfound, int *foundtype) 2071 { 2072 char fpath[strlen(currpath) + 1]; 2073 char *name = fpath; 2074 char *next; 2075 int status; 2076 int type = FILETYPE_DIRECTORY; 2077 struct ext2fs_node *currnode = currroot; 2078 struct ext2fs_node *oldnode = currroot; 2079 2080 strncpy(fpath, currpath, strlen(currpath) + 1); 2081 2082 /* Remove all leading slashes. */ 2083 while (*name == '/') 2084 name++; 2085 2086 if (!*name) { 2087 *currfound = currnode; 2088 return 1; 2089 } 2090 2091 for (;;) { 2092 int found; 2093 2094 /* Extract the actual part from the pathname. */ 2095 next = strchr(name, '/'); 2096 if (next) { 2097 /* Remove all leading slashes. */ 2098 while (*next == '/') 2099 *(next++) = '\0'; 2100 } 2101 2102 if (type != FILETYPE_DIRECTORY) { 2103 ext4fs_free_node(currnode, currroot); 2104 return 0; 2105 } 2106 2107 oldnode = currnode; 2108 2109 /* Iterate over the directory. */ 2110 found = ext4fs_iterate_dir(currnode, name, &currnode, &type); 2111 if (found == 0) 2112 return 0; 2113 2114 if (found == -1) 2115 break; 2116 2117 /* Read in the symlink and follow it. */ 2118 if (type == FILETYPE_SYMLINK) { 2119 char *symlink; 2120 2121 /* Test if the symlink does not loop. */ 2122 if (++symlinknest == 8) { 2123 ext4fs_free_node(currnode, currroot); 2124 ext4fs_free_node(oldnode, currroot); 2125 return 0; 2126 } 2127 2128 symlink = ext4fs_read_symlink(currnode); 2129 ext4fs_free_node(currnode, currroot); 2130 2131 if (!symlink) { 2132 ext4fs_free_node(oldnode, currroot); 2133 return 0; 2134 } 2135 2136 debug("Got symlink >%s<\n", symlink); 2137 2138 if (symlink[0] == '/') { 2139 ext4fs_free_node(oldnode, currroot); 2140 oldnode = &ext4fs_root->diropen; 2141 } 2142 2143 /* Lookup the node the symlink points to. */ 2144 status = ext4fs_find_file1(symlink, oldnode, 2145 &currnode, &type); 2146 2147 free(symlink); 2148 2149 if (status == 0) { 2150 ext4fs_free_node(oldnode, currroot); 2151 return 0; 2152 } 2153 } 2154 2155 ext4fs_free_node(oldnode, currroot); 2156 2157 /* Found the node! */ 2158 if (!next || *next == '\0') { 2159 *currfound = currnode; 2160 *foundtype = type; 2161 return 1; 2162 } 2163 name = next; 2164 } 2165 return -1; 2166 } 2167 2168 int ext4fs_find_file(const char *path, struct ext2fs_node *rootnode, 2169 struct ext2fs_node **foundnode, int expecttype) 2170 { 2171 int status; 2172 int foundtype = FILETYPE_DIRECTORY; 2173 2174 symlinknest = 0; 2175 if (!path) 2176 return 0; 2177 2178 status = ext4fs_find_file1(path, rootnode, foundnode, &foundtype); 2179 if (status == 0) 2180 return 0; 2181 2182 /* Check if the node that was found was of the expected type. */ 2183 if ((expecttype == FILETYPE_REG) && (foundtype != expecttype)) 2184 return 0; 2185 else if ((expecttype == FILETYPE_DIRECTORY) 2186 && (foundtype != expecttype)) 2187 return 0; 2188 2189 return 1; 2190 } 2191 2192 int ext4fs_open(const char *filename, loff_t *len) 2193 { 2194 struct ext2fs_node *fdiro = NULL; 2195 int status; 2196 2197 if (ext4fs_root == NULL) 2198 return -1; 2199 2200 ext4fs_file = NULL; 2201 status = ext4fs_find_file(filename, &ext4fs_root->diropen, &fdiro, 2202 FILETYPE_REG); 2203 if (status == 0) 2204 goto fail; 2205 2206 if (!fdiro->inode_read) { 2207 status = ext4fs_read_inode(fdiro->data, fdiro->ino, 2208 &fdiro->inode); 2209 if (status == 0) 2210 goto fail; 2211 } 2212 *len = __le32_to_cpu(fdiro->inode.size); 2213 ext4fs_file = fdiro; 2214 2215 return 0; 2216 fail: 2217 ext4fs_free_node(fdiro, &ext4fs_root->diropen); 2218 2219 return -1; 2220 } 2221 2222 int ext4fs_mount(unsigned part_length) 2223 { 2224 struct ext2_data *data; 2225 int status; 2226 struct ext_filesystem *fs = get_fs(); 2227 data = zalloc(SUPERBLOCK_SIZE); 2228 if (!data) 2229 return 0; 2230 2231 /* Read the superblock. */ 2232 status = ext4_read_superblock((char *)&data->sblock); 2233 2234 if (status == 0) 2235 goto fail; 2236 2237 /* Make sure this is an ext2 filesystem. */ 2238 if (__le16_to_cpu(data->sblock.magic) != EXT2_MAGIC) 2239 goto fail; 2240 2241 if (__le32_to_cpu(data->sblock.revision_level == 0)) 2242 fs->inodesz = 128; 2243 else 2244 fs->inodesz = __le16_to_cpu(data->sblock.inode_size); 2245 2246 debug("EXT2 rev %d, inode_size %d\n", 2247 __le32_to_cpu(data->sblock.revision_level), fs->inodesz); 2248 2249 data->diropen.data = data; 2250 data->diropen.ino = 2; 2251 data->diropen.inode_read = 1; 2252 data->inode = &data->diropen.inode; 2253 2254 status = ext4fs_read_inode(data, 2, data->inode); 2255 if (status == 0) 2256 goto fail; 2257 2258 ext4fs_root = data; 2259 2260 return 1; 2261 fail: 2262 printf("Failed to mount ext2 filesystem...\n"); 2263 free(data); 2264 ext4fs_root = NULL; 2265 2266 return 0; 2267 } 2268