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 blk_dread(fs->dev_desc, startblock, 1, sec_buf); 85 temp_ptr = sec_buf; 86 memcpy((temp_ptr + remainder), (unsigned char *)buf, size); 87 blk_dwrite(fs->dev_desc, startblock, 1, sec_buf); 88 } else { 89 if (size >> log2blksz != 0) { 90 blk_dwrite(fs->dev_desc, startblock, size >> log2blksz, 91 (unsigned long *)buf); 92 } else { 93 blk_dread(fs->dev_desc, startblock, 1, sec_buf); 94 temp_ptr = sec_buf; 95 memcpy(temp_ptr, buf, size); 96 blk_dwrite(fs->dev_desc, startblock, 1, 97 (unsigned long *)sec_buf); 98 } 99 } 100 } 101 102 static int _get_new_inode_no(unsigned char *buffer) 103 { 104 struct ext_filesystem *fs = get_fs(); 105 unsigned char input; 106 int operand, status; 107 int count = 1; 108 int j = 0; 109 110 /* get the blocksize of the filesystem */ 111 unsigned char *ptr = buffer; 112 while (*ptr == 255) { 113 ptr++; 114 count += 8; 115 if (count > ext4fs_root->sblock.inodes_per_group) 116 return -1; 117 } 118 119 for (j = 0; j < fs->blksz; j++) { 120 input = *ptr; 121 int i = 0; 122 while (i <= 7) { 123 operand = 1 << i; 124 status = input & operand; 125 if (status) { 126 i++; 127 count++; 128 } else { 129 *ptr |= operand; 130 return count; 131 } 132 } 133 ptr = ptr + 1; 134 } 135 136 return -1; 137 } 138 139 static int _get_new_blk_no(unsigned char *buffer) 140 { 141 unsigned char input; 142 int operand, status; 143 int count = 0; 144 int j = 0; 145 unsigned char *ptr = buffer; 146 struct ext_filesystem *fs = get_fs(); 147 148 if (fs->blksz != 1024) 149 count = 0; 150 else 151 count = 1; 152 153 while (*ptr == 255) { 154 ptr++; 155 count += 8; 156 if (count == (fs->blksz * 8)) 157 return -1; 158 } 159 160 for (j = 0; j < fs->blksz; j++) { 161 input = *ptr; 162 int i = 0; 163 while (i <= 7) { 164 operand = 1 << i; 165 status = input & operand; 166 if (status) { 167 i++; 168 count++; 169 } else { 170 *ptr |= operand; 171 return count; 172 } 173 } 174 ptr = ptr + 1; 175 } 176 177 return -1; 178 } 179 180 int ext4fs_set_block_bmap(long int blockno, unsigned char *buffer, int index) 181 { 182 int i, remainder, status; 183 unsigned char *ptr = buffer; 184 unsigned char operand; 185 i = blockno / 8; 186 remainder = blockno % 8; 187 int blocksize = EXT2_BLOCK_SIZE(ext4fs_root); 188 189 i = i - (index * blocksize); 190 if (blocksize != 1024) { 191 ptr = ptr + i; 192 operand = 1 << remainder; 193 status = *ptr & operand; 194 if (status) 195 return -1; 196 197 *ptr = *ptr | operand; 198 return 0; 199 } else { 200 if (remainder == 0) { 201 ptr = ptr + i - 1; 202 operand = (1 << 7); 203 } else { 204 ptr = ptr + i; 205 operand = (1 << (remainder - 1)); 206 } 207 status = *ptr & operand; 208 if (status) 209 return -1; 210 211 *ptr = *ptr | operand; 212 return 0; 213 } 214 } 215 216 void ext4fs_reset_block_bmap(long int blockno, unsigned char *buffer, int index) 217 { 218 int i, remainder, status; 219 unsigned char *ptr = buffer; 220 unsigned char operand; 221 i = blockno / 8; 222 remainder = blockno % 8; 223 int blocksize = EXT2_BLOCK_SIZE(ext4fs_root); 224 225 i = i - (index * blocksize); 226 if (blocksize != 1024) { 227 ptr = ptr + i; 228 operand = (1 << remainder); 229 status = *ptr & operand; 230 if (status) 231 *ptr = *ptr & ~(operand); 232 } else { 233 if (remainder == 0) { 234 ptr = ptr + i - 1; 235 operand = (1 << 7); 236 } else { 237 ptr = ptr + i; 238 operand = (1 << (remainder - 1)); 239 } 240 status = *ptr & operand; 241 if (status) 242 *ptr = *ptr & ~(operand); 243 } 244 } 245 246 int ext4fs_set_inode_bmap(int inode_no, unsigned char *buffer, int index) 247 { 248 int i, remainder, status; 249 unsigned char *ptr = buffer; 250 unsigned char operand; 251 252 inode_no -= (index * ext4fs_root->sblock.inodes_per_group); 253 i = inode_no / 8; 254 remainder = inode_no % 8; 255 if (remainder == 0) { 256 ptr = ptr + i - 1; 257 operand = (1 << 7); 258 } else { 259 ptr = ptr + i; 260 operand = (1 << (remainder - 1)); 261 } 262 status = *ptr & operand; 263 if (status) 264 return -1; 265 266 *ptr = *ptr | operand; 267 268 return 0; 269 } 270 271 void ext4fs_reset_inode_bmap(int inode_no, unsigned char *buffer, int index) 272 { 273 int i, remainder, status; 274 unsigned char *ptr = buffer; 275 unsigned char operand; 276 277 inode_no -= (index * ext4fs_root->sblock.inodes_per_group); 278 i = inode_no / 8; 279 remainder = inode_no % 8; 280 if (remainder == 0) { 281 ptr = ptr + i - 1; 282 operand = (1 << 7); 283 } else { 284 ptr = ptr + i; 285 operand = (1 << (remainder - 1)); 286 } 287 status = *ptr & operand; 288 if (status) 289 *ptr = *ptr & ~(operand); 290 } 291 292 int ext4fs_checksum_update(unsigned int i) 293 { 294 struct ext2_block_group *desc; 295 struct ext_filesystem *fs = get_fs(); 296 __u16 crc = 0; 297 298 desc = (struct ext2_block_group *)&fs->bgd[i]; 299 if (fs->sb->feature_ro_compat & EXT4_FEATURE_RO_COMPAT_GDT_CSUM) { 300 int offset = offsetof(struct ext2_block_group, bg_checksum); 301 302 crc = ext2fs_crc16(~0, fs->sb->unique_id, 303 sizeof(fs->sb->unique_id)); 304 crc = ext2fs_crc16(crc, &i, sizeof(i)); 305 crc = ext2fs_crc16(crc, desc, offset); 306 offset += sizeof(desc->bg_checksum); /* skip checksum */ 307 assert(offset == sizeof(*desc)); 308 } 309 310 return crc; 311 } 312 313 static int check_void_in_dentry(struct ext2_dirent *dir, char *filename) 314 { 315 int dentry_length; 316 int sizeof_void_space; 317 int new_entry_byte_reqd; 318 short padding_factor = 0; 319 320 if (dir->namelen % 4 != 0) 321 padding_factor = 4 - (dir->namelen % 4); 322 323 dentry_length = sizeof(struct ext2_dirent) + 324 dir->namelen + padding_factor; 325 sizeof_void_space = dir->direntlen - dentry_length; 326 if (sizeof_void_space == 0) 327 return 0; 328 329 padding_factor = 0; 330 if (strlen(filename) % 4 != 0) 331 padding_factor = 4 - (strlen(filename) % 4); 332 333 new_entry_byte_reqd = strlen(filename) + 334 sizeof(struct ext2_dirent) + padding_factor; 335 if (sizeof_void_space >= new_entry_byte_reqd) { 336 dir->direntlen = dentry_length; 337 return sizeof_void_space; 338 } 339 340 return 0; 341 } 342 343 void ext4fs_update_parent_dentry(char *filename, int *p_ino, int file_type) 344 { 345 unsigned int *zero_buffer = NULL; 346 char *root_first_block_buffer = NULL; 347 int direct_blk_idx; 348 long int root_blknr; 349 long int first_block_no_of_root = 0; 350 long int previous_blknr = -1; 351 int totalbytes = 0; 352 short int padding_factor = 0; 353 unsigned int new_entry_byte_reqd; 354 unsigned int last_entry_dirlen; 355 int sizeof_void_space = 0; 356 int templength = 0; 357 int inodeno; 358 int status; 359 struct ext_filesystem *fs = get_fs(); 360 /* directory entry */ 361 struct ext2_dirent *dir; 362 char *temp_dir = NULL; 363 364 zero_buffer = zalloc(fs->blksz); 365 if (!zero_buffer) { 366 printf("No Memory\n"); 367 return; 368 } 369 root_first_block_buffer = zalloc(fs->blksz); 370 if (!root_first_block_buffer) { 371 free(zero_buffer); 372 printf("No Memory\n"); 373 return; 374 } 375 restart: 376 377 /* read the block no allocated to a file */ 378 for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS; 379 direct_blk_idx++) { 380 root_blknr = read_allocated_block(g_parent_inode, 381 direct_blk_idx); 382 if (root_blknr == 0) { 383 first_block_no_of_root = previous_blknr; 384 break; 385 } 386 previous_blknr = root_blknr; 387 } 388 389 status = ext4fs_devread((lbaint_t)first_block_no_of_root 390 * fs->sect_perblk, 391 0, fs->blksz, root_first_block_buffer); 392 if (status == 0) 393 goto fail; 394 395 if (ext4fs_log_journal(root_first_block_buffer, first_block_no_of_root)) 396 goto fail; 397 dir = (struct ext2_dirent *)root_first_block_buffer; 398 totalbytes = 0; 399 while (dir->direntlen > 0) { 400 /* 401 * blocksize-totalbytes because last directory length 402 * i.e. dir->direntlen is free availble space in the 403 * block that means it is a last entry of directory 404 * entry 405 */ 406 407 /* traversing the each directory entry */ 408 if (fs->blksz - totalbytes == dir->direntlen) { 409 if (strlen(filename) % 4 != 0) 410 padding_factor = 4 - (strlen(filename) % 4); 411 412 new_entry_byte_reqd = strlen(filename) + 413 sizeof(struct ext2_dirent) + padding_factor; 414 padding_factor = 0; 415 /* 416 * update last directory entry length to its 417 * length because we are creating new directory 418 * entry 419 */ 420 if (dir->namelen % 4 != 0) 421 padding_factor = 4 - (dir->namelen % 4); 422 423 last_entry_dirlen = dir->namelen + 424 sizeof(struct ext2_dirent) + padding_factor; 425 if ((fs->blksz - totalbytes - last_entry_dirlen) < 426 new_entry_byte_reqd) { 427 printf("1st Block Full:Allocate new block\n"); 428 429 if (direct_blk_idx == INDIRECT_BLOCKS - 1) { 430 printf("Directory exceeds limit\n"); 431 goto fail; 432 } 433 g_parent_inode->b.blocks.dir_blocks 434 [direct_blk_idx] = ext4fs_get_new_blk_no(); 435 if (g_parent_inode->b.blocks.dir_blocks 436 [direct_blk_idx] == -1) { 437 printf("no block left to assign\n"); 438 goto fail; 439 } 440 put_ext4(((uint64_t) 441 ((uint64_t)g_parent_inode->b. 442 blocks.dir_blocks[direct_blk_idx] * 443 (uint64_t)fs->blksz)), zero_buffer, fs->blksz); 444 g_parent_inode->size = 445 g_parent_inode->size + fs->blksz; 446 g_parent_inode->blockcnt = 447 g_parent_inode->blockcnt + fs->sect_perblk; 448 if (ext4fs_put_metadata 449 (root_first_block_buffer, 450 first_block_no_of_root)) 451 goto fail; 452 goto restart; 453 } 454 dir->direntlen = last_entry_dirlen; 455 break; 456 } 457 458 templength = dir->direntlen; 459 totalbytes = totalbytes + templength; 460 sizeof_void_space = check_void_in_dentry(dir, filename); 461 if (sizeof_void_space) 462 break; 463 464 dir = (struct ext2_dirent *)((char *)dir + templength); 465 } 466 467 /* make a pointer ready for creating next directory entry */ 468 templength = dir->direntlen; 469 totalbytes = totalbytes + templength; 470 dir = (struct ext2_dirent *)((char *)dir + templength); 471 472 /* get the next available inode number */ 473 inodeno = ext4fs_get_new_inode_no(); 474 if (inodeno == -1) { 475 printf("no inode left to assign\n"); 476 goto fail; 477 } 478 dir->inode = inodeno; 479 if (sizeof_void_space) 480 dir->direntlen = sizeof_void_space; 481 else 482 dir->direntlen = fs->blksz - totalbytes; 483 484 dir->namelen = strlen(filename); 485 dir->filetype = FILETYPE_REG; /* regular file */ 486 temp_dir = (char *)dir; 487 temp_dir = temp_dir + sizeof(struct ext2_dirent); 488 memcpy(temp_dir, filename, strlen(filename)); 489 490 *p_ino = inodeno; 491 492 /* update or write the 1st block of root inode */ 493 if (ext4fs_put_metadata(root_first_block_buffer, 494 first_block_no_of_root)) 495 goto fail; 496 497 fail: 498 free(zero_buffer); 499 free(root_first_block_buffer); 500 } 501 502 static int search_dir(struct ext2_inode *parent_inode, char *dirname) 503 { 504 int status; 505 int inodeno; 506 int totalbytes; 507 int templength; 508 int direct_blk_idx; 509 long int blknr; 510 int found = 0; 511 char *ptr = NULL; 512 unsigned char *block_buffer = NULL; 513 struct ext2_dirent *dir = NULL; 514 struct ext2_dirent *previous_dir = NULL; 515 struct ext_filesystem *fs = get_fs(); 516 517 /* read the block no allocated to a file */ 518 for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS; 519 direct_blk_idx++) { 520 blknr = read_allocated_block(parent_inode, direct_blk_idx); 521 if (blknr == 0) 522 goto fail; 523 524 /* read the blocks of parenet inode */ 525 block_buffer = zalloc(fs->blksz); 526 if (!block_buffer) 527 goto fail; 528 529 status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 530 0, fs->blksz, (char *)block_buffer); 531 if (status == 0) 532 goto fail; 533 534 dir = (struct ext2_dirent *)block_buffer; 535 ptr = (char *)dir; 536 totalbytes = 0; 537 while (dir->direntlen >= 0) { 538 /* 539 * blocksize-totalbytes because last directory 540 * length i.e.,*dir->direntlen is free availble 541 * space in the block that means 542 * it is a last entry of directory entry 543 */ 544 if (strlen(dirname) == dir->namelen) { 545 if (strncmp(dirname, ptr + 546 sizeof(struct ext2_dirent), 547 dir->namelen) == 0) { 548 previous_dir->direntlen += 549 dir->direntlen; 550 inodeno = dir->inode; 551 dir->inode = 0; 552 found = 1; 553 break; 554 } 555 } 556 557 if (fs->blksz - totalbytes == dir->direntlen) 558 break; 559 560 /* traversing the each directory entry */ 561 templength = dir->direntlen; 562 totalbytes = totalbytes + templength; 563 previous_dir = dir; 564 dir = (struct ext2_dirent *)((char *)dir + templength); 565 ptr = (char *)dir; 566 } 567 568 if (found == 1) { 569 free(block_buffer); 570 block_buffer = NULL; 571 return inodeno; 572 } 573 574 free(block_buffer); 575 block_buffer = NULL; 576 } 577 578 fail: 579 free(block_buffer); 580 581 return -1; 582 } 583 584 static int find_dir_depth(char *dirname) 585 { 586 char *token = strtok(dirname, "/"); 587 int count = 0; 588 while (token != NULL) { 589 token = strtok(NULL, "/"); 590 count++; 591 } 592 return count + 1 + 1; 593 /* 594 * for example for string /home/temp 595 * depth=home(1)+temp(1)+1 extra for NULL; 596 * so count is 4; 597 */ 598 } 599 600 static int parse_path(char **arr, char *dirname) 601 { 602 char *token = strtok(dirname, "/"); 603 int i = 0; 604 605 /* add root */ 606 arr[i] = zalloc(strlen("/") + 1); 607 if (!arr[i]) 608 return -ENOMEM; 609 memcpy(arr[i++], "/", strlen("/")); 610 611 /* add each path entry after root */ 612 while (token != NULL) { 613 arr[i] = zalloc(strlen(token) + 1); 614 if (!arr[i]) 615 return -ENOMEM; 616 memcpy(arr[i++], token, strlen(token)); 617 token = strtok(NULL, "/"); 618 } 619 arr[i] = NULL; 620 621 return 0; 622 } 623 624 int ext4fs_iget(int inode_no, struct ext2_inode *inode) 625 { 626 if (ext4fs_read_inode(ext4fs_root, inode_no, inode) == 0) 627 return -1; 628 629 return 0; 630 } 631 632 /* 633 * Function: ext4fs_get_parent_inode_num 634 * Return Value: inode Number of the parent directory of file/Directory to be 635 * created 636 * dirname : Input parmater, input path name of the file/directory to be created 637 * dname : Output parameter, to be filled with the name of the directory 638 * extracted from dirname 639 */ 640 int ext4fs_get_parent_inode_num(const char *dirname, char *dname, int flags) 641 { 642 int i; 643 int depth = 0; 644 int matched_inode_no; 645 int result_inode_no = -1; 646 char **ptr = NULL; 647 char *depth_dirname = NULL; 648 char *parse_dirname = NULL; 649 struct ext2_inode *parent_inode = NULL; 650 struct ext2_inode *first_inode = NULL; 651 struct ext2_inode temp_inode; 652 653 if (*dirname != '/') { 654 printf("Please supply Absolute path\n"); 655 return -1; 656 } 657 658 /* TODO: input validation make equivalent to linux */ 659 depth_dirname = zalloc(strlen(dirname) + 1); 660 if (!depth_dirname) 661 return -ENOMEM; 662 663 memcpy(depth_dirname, dirname, strlen(dirname)); 664 depth = find_dir_depth(depth_dirname); 665 parse_dirname = zalloc(strlen(dirname) + 1); 666 if (!parse_dirname) 667 goto fail; 668 memcpy(parse_dirname, dirname, strlen(dirname)); 669 670 /* allocate memory for each directory level */ 671 ptr = zalloc((depth) * sizeof(char *)); 672 if (!ptr) 673 goto fail; 674 if (parse_path(ptr, parse_dirname)) 675 goto fail; 676 parent_inode = zalloc(sizeof(struct ext2_inode)); 677 if (!parent_inode) 678 goto fail; 679 first_inode = zalloc(sizeof(struct ext2_inode)); 680 if (!first_inode) 681 goto fail; 682 memcpy(parent_inode, ext4fs_root->inode, sizeof(struct ext2_inode)); 683 memcpy(first_inode, parent_inode, sizeof(struct ext2_inode)); 684 if (flags & F_FILE) 685 result_inode_no = EXT2_ROOT_INO; 686 for (i = 1; i < depth; i++) { 687 matched_inode_no = search_dir(parent_inode, ptr[i]); 688 if (matched_inode_no == -1) { 689 if (ptr[i + 1] == NULL && i == 1) { 690 result_inode_no = EXT2_ROOT_INO; 691 goto end; 692 } else { 693 if (ptr[i + 1] == NULL) 694 break; 695 printf("Invalid path\n"); 696 result_inode_no = -1; 697 goto fail; 698 } 699 } else { 700 if (ptr[i + 1] != NULL) { 701 memset(parent_inode, '\0', 702 sizeof(struct ext2_inode)); 703 if (ext4fs_iget(matched_inode_no, 704 parent_inode)) { 705 result_inode_no = -1; 706 goto fail; 707 } 708 result_inode_no = matched_inode_no; 709 } else { 710 break; 711 } 712 } 713 } 714 715 end: 716 if (i == 1) 717 matched_inode_no = search_dir(first_inode, ptr[i]); 718 else 719 matched_inode_no = search_dir(parent_inode, ptr[i]); 720 721 if (matched_inode_no != -1) { 722 ext4fs_iget(matched_inode_no, &temp_inode); 723 if (temp_inode.mode & S_IFDIR) { 724 printf("It is a Directory\n"); 725 result_inode_no = -1; 726 goto fail; 727 } 728 } 729 730 if (strlen(ptr[i]) > 256) { 731 result_inode_no = -1; 732 goto fail; 733 } 734 memcpy(dname, ptr[i], strlen(ptr[i])); 735 736 fail: 737 free(depth_dirname); 738 free(parse_dirname); 739 for (i = 0; i < depth; i++) { 740 if (!ptr[i]) 741 break; 742 free(ptr[i]); 743 } 744 free(ptr); 745 free(parent_inode); 746 free(first_inode); 747 748 return result_inode_no; 749 } 750 751 static int check_filename(char *filename, unsigned int blknr) 752 { 753 unsigned int first_block_no_of_root; 754 int totalbytes = 0; 755 int templength = 0; 756 int status, inodeno; 757 int found = 0; 758 char *root_first_block_buffer = NULL; 759 char *root_first_block_addr = NULL; 760 struct ext2_dirent *dir = NULL; 761 struct ext2_dirent *previous_dir = NULL; 762 char *ptr = NULL; 763 struct ext_filesystem *fs = get_fs(); 764 int ret = -1; 765 766 /* get the first block of root */ 767 first_block_no_of_root = blknr; 768 root_first_block_buffer = zalloc(fs->blksz); 769 if (!root_first_block_buffer) 770 return -ENOMEM; 771 root_first_block_addr = root_first_block_buffer; 772 status = ext4fs_devread((lbaint_t)first_block_no_of_root * 773 fs->sect_perblk, 0, 774 fs->blksz, root_first_block_buffer); 775 if (status == 0) 776 goto fail; 777 778 if (ext4fs_log_journal(root_first_block_buffer, first_block_no_of_root)) 779 goto fail; 780 dir = (struct ext2_dirent *)root_first_block_buffer; 781 ptr = (char *)dir; 782 totalbytes = 0; 783 while (dir->direntlen >= 0) { 784 /* 785 * blocksize-totalbytes because last 786 * directory length i.e., *dir->direntlen 787 * is free availble space in the block that 788 * means it is a last entry of directory entry 789 */ 790 if (strlen(filename) == dir->namelen) { 791 if (strncmp(filename, ptr + sizeof(struct ext2_dirent), 792 dir->namelen) == 0) { 793 printf("file found deleting\n"); 794 previous_dir->direntlen += dir->direntlen; 795 inodeno = dir->inode; 796 dir->inode = 0; 797 found = 1; 798 break; 799 } 800 } 801 802 if (fs->blksz - totalbytes == dir->direntlen) 803 break; 804 805 /* traversing the each directory entry */ 806 templength = dir->direntlen; 807 totalbytes = totalbytes + templength; 808 previous_dir = dir; 809 dir = (struct ext2_dirent *)((char *)dir + templength); 810 ptr = (char *)dir; 811 } 812 813 814 if (found == 1) { 815 if (ext4fs_put_metadata(root_first_block_addr, 816 first_block_no_of_root)) 817 goto fail; 818 ret = inodeno; 819 } 820 fail: 821 free(root_first_block_buffer); 822 823 return ret; 824 } 825 826 int ext4fs_filename_check(char *filename) 827 { 828 short direct_blk_idx = 0; 829 long int blknr = -1; 830 int inodeno = -1; 831 832 /* read the block no allocated to a file */ 833 for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS; 834 direct_blk_idx++) { 835 blknr = read_allocated_block(g_parent_inode, direct_blk_idx); 836 if (blknr == 0) 837 break; 838 inodeno = check_filename(filename, blknr); 839 if (inodeno != -1) 840 return inodeno; 841 } 842 843 return -1; 844 } 845 846 long int ext4fs_get_new_blk_no(void) 847 { 848 short i; 849 short status; 850 int remainder; 851 unsigned int bg_idx; 852 static int prev_bg_bitmap_index = -1; 853 unsigned int blk_per_grp = ext4fs_root->sblock.blocks_per_group; 854 struct ext_filesystem *fs = get_fs(); 855 char *journal_buffer = zalloc(fs->blksz); 856 char *zero_buffer = zalloc(fs->blksz); 857 if (!journal_buffer || !zero_buffer) 858 goto fail; 859 struct ext2_block_group *bgd = (struct ext2_block_group *)fs->gdtable; 860 861 if (fs->first_pass_bbmap == 0) { 862 for (i = 0; i < fs->no_blkgrp; i++) { 863 if (bgd[i].free_blocks) { 864 if (bgd[i].bg_flags & EXT4_BG_BLOCK_UNINIT) { 865 put_ext4(((uint64_t) ((uint64_t)bgd[i].block_id * 866 (uint64_t)fs->blksz)), 867 zero_buffer, fs->blksz); 868 bgd[i].bg_flags = 869 bgd[i]. 870 bg_flags & ~EXT4_BG_BLOCK_UNINIT; 871 memcpy(fs->blk_bmaps[i], zero_buffer, 872 fs->blksz); 873 } 874 fs->curr_blkno = 875 _get_new_blk_no(fs->blk_bmaps[i]); 876 if (fs->curr_blkno == -1) 877 /* if block bitmap is completely fill */ 878 continue; 879 fs->curr_blkno = fs->curr_blkno + 880 (i * fs->blksz * 8); 881 fs->first_pass_bbmap++; 882 bgd[i].free_blocks--; 883 fs->sb->free_blocks--; 884 status = ext4fs_devread((lbaint_t) 885 bgd[i].block_id * 886 fs->sect_perblk, 0, 887 fs->blksz, 888 journal_buffer); 889 if (status == 0) 890 goto fail; 891 if (ext4fs_log_journal(journal_buffer, 892 bgd[i].block_id)) 893 goto fail; 894 goto success; 895 } else { 896 debug("no space left on block group %d\n", i); 897 } 898 } 899 900 goto fail; 901 } else { 902 restart: 903 fs->curr_blkno++; 904 /* get the blockbitmap index respective to blockno */ 905 bg_idx = fs->curr_blkno / blk_per_grp; 906 if (fs->blksz == 1024) { 907 remainder = fs->curr_blkno % blk_per_grp; 908 if (!remainder) 909 bg_idx--; 910 } 911 912 /* 913 * To skip completely filled block group bitmaps 914 * Optimize the block allocation 915 */ 916 if (bg_idx >= fs->no_blkgrp) 917 goto fail; 918 919 if (bgd[bg_idx].free_blocks == 0) { 920 debug("block group %u is full. Skipping\n", bg_idx); 921 fs->curr_blkno = fs->curr_blkno + blk_per_grp; 922 fs->curr_blkno--; 923 goto restart; 924 } 925 926 if (bgd[bg_idx].bg_flags & EXT4_BG_BLOCK_UNINIT) { 927 memset(zero_buffer, '\0', fs->blksz); 928 put_ext4(((uint64_t) ((uint64_t)bgd[bg_idx].block_id * 929 (uint64_t)fs->blksz)), zero_buffer, fs->blksz); 930 memcpy(fs->blk_bmaps[bg_idx], zero_buffer, fs->blksz); 931 bgd[bg_idx].bg_flags = bgd[bg_idx].bg_flags & 932 ~EXT4_BG_BLOCK_UNINIT; 933 } 934 935 if (ext4fs_set_block_bmap(fs->curr_blkno, fs->blk_bmaps[bg_idx], 936 bg_idx) != 0) { 937 debug("going for restart for the block no %ld %u\n", 938 fs->curr_blkno, bg_idx); 939 goto restart; 940 } 941 942 /* journal backup */ 943 if (prev_bg_bitmap_index != bg_idx) { 944 memset(journal_buffer, '\0', fs->blksz); 945 status = ext4fs_devread((lbaint_t)bgd[bg_idx].block_id 946 * fs->sect_perblk, 947 0, fs->blksz, journal_buffer); 948 if (status == 0) 949 goto fail; 950 if (ext4fs_log_journal(journal_buffer, 951 bgd[bg_idx].block_id)) 952 goto fail; 953 954 prev_bg_bitmap_index = bg_idx; 955 } 956 bgd[bg_idx].free_blocks--; 957 fs->sb->free_blocks--; 958 goto success; 959 } 960 success: 961 free(journal_buffer); 962 free(zero_buffer); 963 964 return fs->curr_blkno; 965 fail: 966 free(journal_buffer); 967 free(zero_buffer); 968 969 return -1; 970 } 971 972 int ext4fs_get_new_inode_no(void) 973 { 974 short i; 975 short status; 976 unsigned int ibmap_idx; 977 static int prev_inode_bitmap_index = -1; 978 unsigned int inodes_per_grp = ext4fs_root->sblock.inodes_per_group; 979 struct ext_filesystem *fs = get_fs(); 980 char *journal_buffer = zalloc(fs->blksz); 981 char *zero_buffer = zalloc(fs->blksz); 982 if (!journal_buffer || !zero_buffer) 983 goto fail; 984 struct ext2_block_group *bgd = (struct ext2_block_group *)fs->gdtable; 985 986 if (fs->first_pass_ibmap == 0) { 987 for (i = 0; i < fs->no_blkgrp; i++) { 988 if (bgd[i].free_inodes) { 989 if (bgd[i].bg_itable_unused != 990 bgd[i].free_inodes) 991 bgd[i].bg_itable_unused = 992 bgd[i].free_inodes; 993 if (bgd[i].bg_flags & EXT4_BG_INODE_UNINIT) { 994 put_ext4(((uint64_t) 995 ((uint64_t)bgd[i].inode_id * 996 (uint64_t)fs->blksz)), 997 zero_buffer, fs->blksz); 998 bgd[i].bg_flags = bgd[i].bg_flags & 999 ~EXT4_BG_INODE_UNINIT; 1000 memcpy(fs->inode_bmaps[i], 1001 zero_buffer, fs->blksz); 1002 } 1003 fs->curr_inode_no = 1004 _get_new_inode_no(fs->inode_bmaps[i]); 1005 if (fs->curr_inode_no == -1) 1006 /* if block bitmap is completely fill */ 1007 continue; 1008 fs->curr_inode_no = fs->curr_inode_no + 1009 (i * inodes_per_grp); 1010 fs->first_pass_ibmap++; 1011 bgd[i].free_inodes--; 1012 bgd[i].bg_itable_unused--; 1013 fs->sb->free_inodes--; 1014 status = ext4fs_devread((lbaint_t) 1015 bgd[i].inode_id * 1016 fs->sect_perblk, 0, 1017 fs->blksz, 1018 journal_buffer); 1019 if (status == 0) 1020 goto fail; 1021 if (ext4fs_log_journal(journal_buffer, 1022 bgd[i].inode_id)) 1023 goto fail; 1024 goto success; 1025 } else 1026 debug("no inode left on block group %d\n", i); 1027 } 1028 goto fail; 1029 } else { 1030 restart: 1031 fs->curr_inode_no++; 1032 /* get the blockbitmap index respective to blockno */ 1033 ibmap_idx = fs->curr_inode_no / inodes_per_grp; 1034 if (bgd[ibmap_idx].bg_flags & EXT4_BG_INODE_UNINIT) { 1035 memset(zero_buffer, '\0', fs->blksz); 1036 put_ext4(((uint64_t) ((uint64_t)bgd[ibmap_idx].inode_id * 1037 (uint64_t)fs->blksz)), zero_buffer, 1038 fs->blksz); 1039 bgd[ibmap_idx].bg_flags = 1040 bgd[ibmap_idx].bg_flags & ~EXT4_BG_INODE_UNINIT; 1041 memcpy(fs->inode_bmaps[ibmap_idx], zero_buffer, 1042 fs->blksz); 1043 } 1044 1045 if (ext4fs_set_inode_bmap(fs->curr_inode_no, 1046 fs->inode_bmaps[ibmap_idx], 1047 ibmap_idx) != 0) { 1048 debug("going for restart for the block no %d %u\n", 1049 fs->curr_inode_no, ibmap_idx); 1050 goto restart; 1051 } 1052 1053 /* journal backup */ 1054 if (prev_inode_bitmap_index != ibmap_idx) { 1055 memset(journal_buffer, '\0', fs->blksz); 1056 status = ext4fs_devread((lbaint_t) 1057 bgd[ibmap_idx].inode_id 1058 * fs->sect_perblk, 1059 0, fs->blksz, journal_buffer); 1060 if (status == 0) 1061 goto fail; 1062 if (ext4fs_log_journal(journal_buffer, 1063 bgd[ibmap_idx].inode_id)) 1064 goto fail; 1065 prev_inode_bitmap_index = ibmap_idx; 1066 } 1067 if (bgd[ibmap_idx].bg_itable_unused != 1068 bgd[ibmap_idx].free_inodes) 1069 bgd[ibmap_idx].bg_itable_unused = 1070 bgd[ibmap_idx].free_inodes; 1071 bgd[ibmap_idx].free_inodes--; 1072 bgd[ibmap_idx].bg_itable_unused--; 1073 fs->sb->free_inodes--; 1074 goto success; 1075 } 1076 1077 success: 1078 free(journal_buffer); 1079 free(zero_buffer); 1080 1081 return fs->curr_inode_no; 1082 fail: 1083 free(journal_buffer); 1084 free(zero_buffer); 1085 1086 return -1; 1087 1088 } 1089 1090 1091 static void alloc_single_indirect_block(struct ext2_inode *file_inode, 1092 unsigned int *total_remaining_blocks, 1093 unsigned int *no_blks_reqd) 1094 { 1095 short i; 1096 short status; 1097 long int actual_block_no; 1098 long int si_blockno; 1099 /* si :single indirect */ 1100 unsigned int *si_buffer = NULL; 1101 unsigned int *si_start_addr = NULL; 1102 struct ext_filesystem *fs = get_fs(); 1103 1104 if (*total_remaining_blocks != 0) { 1105 si_buffer = zalloc(fs->blksz); 1106 if (!si_buffer) { 1107 printf("No Memory\n"); 1108 return; 1109 } 1110 si_start_addr = si_buffer; 1111 si_blockno = ext4fs_get_new_blk_no(); 1112 if (si_blockno == -1) { 1113 printf("no block left to assign\n"); 1114 goto fail; 1115 } 1116 (*no_blks_reqd)++; 1117 debug("SIPB %ld: %u\n", si_blockno, *total_remaining_blocks); 1118 1119 status = ext4fs_devread((lbaint_t)si_blockno * fs->sect_perblk, 1120 0, fs->blksz, (char *)si_buffer); 1121 memset(si_buffer, '\0', fs->blksz); 1122 if (status == 0) 1123 goto fail; 1124 1125 for (i = 0; i < (fs->blksz / sizeof(int)); i++) { 1126 actual_block_no = ext4fs_get_new_blk_no(); 1127 if (actual_block_no == -1) { 1128 printf("no block left to assign\n"); 1129 goto fail; 1130 } 1131 *si_buffer = actual_block_no; 1132 debug("SIAB %u: %u\n", *si_buffer, 1133 *total_remaining_blocks); 1134 1135 si_buffer++; 1136 (*total_remaining_blocks)--; 1137 if (*total_remaining_blocks == 0) 1138 break; 1139 } 1140 1141 /* write the block to disk */ 1142 put_ext4(((uint64_t) ((uint64_t)si_blockno * (uint64_t)fs->blksz)), 1143 si_start_addr, fs->blksz); 1144 file_inode->b.blocks.indir_block = si_blockno; 1145 } 1146 fail: 1147 free(si_start_addr); 1148 } 1149 1150 static void alloc_double_indirect_block(struct ext2_inode *file_inode, 1151 unsigned int *total_remaining_blocks, 1152 unsigned int *no_blks_reqd) 1153 { 1154 short i; 1155 short j; 1156 short status; 1157 long int actual_block_no; 1158 /* di:double indirect */ 1159 long int di_blockno_parent; 1160 long int di_blockno_child; 1161 unsigned int *di_parent_buffer = NULL; 1162 unsigned int *di_child_buff = NULL; 1163 unsigned int *di_block_start_addr = NULL; 1164 unsigned int *di_child_buff_start = NULL; 1165 struct ext_filesystem *fs = get_fs(); 1166 1167 if (*total_remaining_blocks != 0) { 1168 /* double indirect parent block connecting to inode */ 1169 di_blockno_parent = ext4fs_get_new_blk_no(); 1170 if (di_blockno_parent == -1) { 1171 printf("no block left to assign\n"); 1172 goto fail; 1173 } 1174 di_parent_buffer = zalloc(fs->blksz); 1175 if (!di_parent_buffer) 1176 goto fail; 1177 1178 di_block_start_addr = di_parent_buffer; 1179 (*no_blks_reqd)++; 1180 debug("DIPB %ld: %u\n", di_blockno_parent, 1181 *total_remaining_blocks); 1182 1183 status = ext4fs_devread((lbaint_t)di_blockno_parent * 1184 fs->sect_perblk, 0, 1185 fs->blksz, (char *)di_parent_buffer); 1186 1187 if (!status) { 1188 printf("%s: Device read error!\n", __func__); 1189 goto fail; 1190 } 1191 memset(di_parent_buffer, '\0', fs->blksz); 1192 1193 /* 1194 * start:for each double indirect parent 1195 * block create one more block 1196 */ 1197 for (i = 0; i < (fs->blksz / sizeof(int)); i++) { 1198 di_blockno_child = ext4fs_get_new_blk_no(); 1199 if (di_blockno_child == -1) { 1200 printf("no block left to assign\n"); 1201 goto fail; 1202 } 1203 di_child_buff = zalloc(fs->blksz); 1204 if (!di_child_buff) 1205 goto fail; 1206 1207 di_child_buff_start = di_child_buff; 1208 *di_parent_buffer = di_blockno_child; 1209 di_parent_buffer++; 1210 (*no_blks_reqd)++; 1211 debug("DICB %ld: %u\n", di_blockno_child, 1212 *total_remaining_blocks); 1213 1214 status = ext4fs_devread((lbaint_t)di_blockno_child * 1215 fs->sect_perblk, 0, 1216 fs->blksz, 1217 (char *)di_child_buff); 1218 1219 if (!status) { 1220 printf("%s: Device read error!\n", __func__); 1221 goto fail; 1222 } 1223 memset(di_child_buff, '\0', fs->blksz); 1224 /* filling of actual datablocks for each child */ 1225 for (j = 0; j < (fs->blksz / sizeof(int)); j++) { 1226 actual_block_no = ext4fs_get_new_blk_no(); 1227 if (actual_block_no == -1) { 1228 printf("no block left to assign\n"); 1229 goto fail; 1230 } 1231 *di_child_buff = actual_block_no; 1232 debug("DIAB %ld: %u\n", actual_block_no, 1233 *total_remaining_blocks); 1234 1235 di_child_buff++; 1236 (*total_remaining_blocks)--; 1237 if (*total_remaining_blocks == 0) 1238 break; 1239 } 1240 /* write the block table */ 1241 put_ext4(((uint64_t) ((uint64_t)di_blockno_child * (uint64_t)fs->blksz)), 1242 di_child_buff_start, fs->blksz); 1243 free(di_child_buff_start); 1244 di_child_buff_start = NULL; 1245 1246 if (*total_remaining_blocks == 0) 1247 break; 1248 } 1249 put_ext4(((uint64_t) ((uint64_t)di_blockno_parent * (uint64_t)fs->blksz)), 1250 di_block_start_addr, fs->blksz); 1251 file_inode->b.blocks.double_indir_block = di_blockno_parent; 1252 } 1253 fail: 1254 free(di_block_start_addr); 1255 } 1256 1257 static void alloc_triple_indirect_block(struct ext2_inode *file_inode, 1258 unsigned int *total_remaining_blocks, 1259 unsigned int *no_blks_reqd) 1260 { 1261 short i; 1262 short j; 1263 short k; 1264 long int actual_block_no; 1265 /* ti: Triple Indirect */ 1266 long int ti_gp_blockno; 1267 long int ti_parent_blockno; 1268 long int ti_child_blockno; 1269 unsigned int *ti_gp_buff = NULL; 1270 unsigned int *ti_parent_buff = NULL; 1271 unsigned int *ti_child_buff = NULL; 1272 unsigned int *ti_gp_buff_start_addr = NULL; 1273 unsigned int *ti_pbuff_start_addr = NULL; 1274 unsigned int *ti_cbuff_start_addr = NULL; 1275 struct ext_filesystem *fs = get_fs(); 1276 if (*total_remaining_blocks != 0) { 1277 /* triple indirect grand parent block connecting to inode */ 1278 ti_gp_blockno = ext4fs_get_new_blk_no(); 1279 if (ti_gp_blockno == -1) { 1280 printf("no block left to assign\n"); 1281 return; 1282 } 1283 ti_gp_buff = zalloc(fs->blksz); 1284 if (!ti_gp_buff) 1285 return; 1286 1287 ti_gp_buff_start_addr = ti_gp_buff; 1288 (*no_blks_reqd)++; 1289 debug("TIGPB %ld: %u\n", ti_gp_blockno, 1290 *total_remaining_blocks); 1291 1292 /* for each 4 byte grand parent entry create one more block */ 1293 for (i = 0; i < (fs->blksz / sizeof(int)); i++) { 1294 ti_parent_blockno = ext4fs_get_new_blk_no(); 1295 if (ti_parent_blockno == -1) { 1296 printf("no block left to assign\n"); 1297 goto fail; 1298 } 1299 ti_parent_buff = zalloc(fs->blksz); 1300 if (!ti_parent_buff) 1301 goto fail; 1302 1303 ti_pbuff_start_addr = ti_parent_buff; 1304 *ti_gp_buff = ti_parent_blockno; 1305 ti_gp_buff++; 1306 (*no_blks_reqd)++; 1307 debug("TIPB %ld: %u\n", ti_parent_blockno, 1308 *total_remaining_blocks); 1309 1310 /* for each 4 byte entry parent create one more block */ 1311 for (j = 0; j < (fs->blksz / sizeof(int)); j++) { 1312 ti_child_blockno = ext4fs_get_new_blk_no(); 1313 if (ti_child_blockno == -1) { 1314 printf("no block left assign\n"); 1315 goto fail1; 1316 } 1317 ti_child_buff = zalloc(fs->blksz); 1318 if (!ti_child_buff) 1319 goto fail1; 1320 1321 ti_cbuff_start_addr = ti_child_buff; 1322 *ti_parent_buff = ti_child_blockno; 1323 ti_parent_buff++; 1324 (*no_blks_reqd)++; 1325 debug("TICB %ld: %u\n", ti_parent_blockno, 1326 *total_remaining_blocks); 1327 1328 /* fill actual datablocks for each child */ 1329 for (k = 0; k < (fs->blksz / sizeof(int)); 1330 k++) { 1331 actual_block_no = 1332 ext4fs_get_new_blk_no(); 1333 if (actual_block_no == -1) { 1334 printf("no block left\n"); 1335 free(ti_cbuff_start_addr); 1336 goto fail1; 1337 } 1338 *ti_child_buff = actual_block_no; 1339 debug("TIAB %ld: %u\n", actual_block_no, 1340 *total_remaining_blocks); 1341 1342 ti_child_buff++; 1343 (*total_remaining_blocks)--; 1344 if (*total_remaining_blocks == 0) 1345 break; 1346 } 1347 /* write the child block */ 1348 put_ext4(((uint64_t) ((uint64_t)ti_child_blockno * 1349 (uint64_t)fs->blksz)), 1350 ti_cbuff_start_addr, fs->blksz); 1351 free(ti_cbuff_start_addr); 1352 1353 if (*total_remaining_blocks == 0) 1354 break; 1355 } 1356 /* write the parent block */ 1357 put_ext4(((uint64_t) ((uint64_t)ti_parent_blockno * (uint64_t)fs->blksz)), 1358 ti_pbuff_start_addr, fs->blksz); 1359 free(ti_pbuff_start_addr); 1360 1361 if (*total_remaining_blocks == 0) 1362 break; 1363 } 1364 /* write the grand parent block */ 1365 put_ext4(((uint64_t) ((uint64_t)ti_gp_blockno * (uint64_t)fs->blksz)), 1366 ti_gp_buff_start_addr, fs->blksz); 1367 file_inode->b.blocks.triple_indir_block = ti_gp_blockno; 1368 free(ti_gp_buff_start_addr); 1369 return; 1370 } 1371 fail1: 1372 free(ti_pbuff_start_addr); 1373 fail: 1374 free(ti_gp_buff_start_addr); 1375 } 1376 1377 void ext4fs_allocate_blocks(struct ext2_inode *file_inode, 1378 unsigned int total_remaining_blocks, 1379 unsigned int *total_no_of_block) 1380 { 1381 short i; 1382 long int direct_blockno; 1383 unsigned int no_blks_reqd = 0; 1384 1385 /* allocation of direct blocks */ 1386 for (i = 0; total_remaining_blocks && i < INDIRECT_BLOCKS; i++) { 1387 direct_blockno = ext4fs_get_new_blk_no(); 1388 if (direct_blockno == -1) { 1389 printf("no block left to assign\n"); 1390 return; 1391 } 1392 file_inode->b.blocks.dir_blocks[i] = direct_blockno; 1393 debug("DB %ld: %u\n", direct_blockno, total_remaining_blocks); 1394 1395 total_remaining_blocks--; 1396 } 1397 1398 alloc_single_indirect_block(file_inode, &total_remaining_blocks, 1399 &no_blks_reqd); 1400 alloc_double_indirect_block(file_inode, &total_remaining_blocks, 1401 &no_blks_reqd); 1402 alloc_triple_indirect_block(file_inode, &total_remaining_blocks, 1403 &no_blks_reqd); 1404 *total_no_of_block += no_blks_reqd; 1405 } 1406 1407 #endif 1408 1409 static struct ext4_extent_header *ext4fs_get_extent_block 1410 (struct ext2_data *data, char *buf, 1411 struct ext4_extent_header *ext_block, 1412 uint32_t fileblock, int log2_blksz) 1413 { 1414 struct ext4_extent_idx *index; 1415 unsigned long long block; 1416 int blksz = EXT2_BLOCK_SIZE(data); 1417 int i; 1418 1419 while (1) { 1420 index = (struct ext4_extent_idx *)(ext_block + 1); 1421 1422 if (le16_to_cpu(ext_block->eh_magic) != EXT4_EXT_MAGIC) 1423 return 0; 1424 1425 if (ext_block->eh_depth == 0) 1426 return ext_block; 1427 i = -1; 1428 do { 1429 i++; 1430 if (i >= le16_to_cpu(ext_block->eh_entries)) 1431 break; 1432 } while (fileblock >= le32_to_cpu(index[i].ei_block)); 1433 1434 if (--i < 0) 1435 return 0; 1436 1437 block = le16_to_cpu(index[i].ei_leaf_hi); 1438 block = (block << 32) + le32_to_cpu(index[i].ei_leaf_lo); 1439 1440 if (ext4fs_devread((lbaint_t)block << log2_blksz, 0, blksz, 1441 buf)) 1442 ext_block = (struct ext4_extent_header *)buf; 1443 else 1444 return 0; 1445 } 1446 } 1447 1448 static int ext4fs_blockgroup 1449 (struct ext2_data *data, int group, struct ext2_block_group *blkgrp) 1450 { 1451 long int blkno; 1452 unsigned int blkoff, desc_per_blk; 1453 int log2blksz = get_fs()->dev_desc->log2blksz; 1454 1455 desc_per_blk = EXT2_BLOCK_SIZE(data) / sizeof(struct ext2_block_group); 1456 1457 blkno = __le32_to_cpu(data->sblock.first_data_block) + 1 + 1458 group / desc_per_blk; 1459 blkoff = (group % desc_per_blk) * sizeof(struct ext2_block_group); 1460 1461 debug("ext4fs read %d group descriptor (blkno %ld blkoff %u)\n", 1462 group, blkno, blkoff); 1463 1464 return ext4fs_devread((lbaint_t)blkno << 1465 (LOG2_BLOCK_SIZE(data) - log2blksz), 1466 blkoff, sizeof(struct ext2_block_group), 1467 (char *)blkgrp); 1468 } 1469 1470 int ext4fs_read_inode(struct ext2_data *data, int ino, struct ext2_inode *inode) 1471 { 1472 struct ext2_block_group blkgrp; 1473 struct ext2_sblock *sblock = &data->sblock; 1474 struct ext_filesystem *fs = get_fs(); 1475 int log2blksz = get_fs()->dev_desc->log2blksz; 1476 int inodes_per_block, status; 1477 long int blkno; 1478 unsigned int blkoff; 1479 1480 /* It is easier to calculate if the first inode is 0. */ 1481 ino--; 1482 status = ext4fs_blockgroup(data, ino / __le32_to_cpu 1483 (sblock->inodes_per_group), &blkgrp); 1484 if (status == 0) 1485 return 0; 1486 1487 inodes_per_block = EXT2_BLOCK_SIZE(data) / fs->inodesz; 1488 blkno = __le32_to_cpu(blkgrp.inode_table_id) + 1489 (ino % __le32_to_cpu(sblock->inodes_per_group)) / inodes_per_block; 1490 blkoff = (ino % inodes_per_block) * fs->inodesz; 1491 /* Read the inode. */ 1492 status = ext4fs_devread((lbaint_t)blkno << (LOG2_BLOCK_SIZE(data) - 1493 log2blksz), blkoff, 1494 sizeof(struct ext2_inode), (char *)inode); 1495 if (status == 0) 1496 return 0; 1497 1498 return 1; 1499 } 1500 1501 long int read_allocated_block(struct ext2_inode *inode, int fileblock) 1502 { 1503 long int blknr; 1504 int blksz; 1505 int log2_blksz; 1506 int status; 1507 long int rblock; 1508 long int perblock_parent; 1509 long int perblock_child; 1510 unsigned long long start; 1511 /* get the blocksize of the filesystem */ 1512 blksz = EXT2_BLOCK_SIZE(ext4fs_root); 1513 log2_blksz = LOG2_BLOCK_SIZE(ext4fs_root) 1514 - get_fs()->dev_desc->log2blksz; 1515 1516 if (le32_to_cpu(inode->flags) & EXT4_EXTENTS_FL) { 1517 char *buf = zalloc(blksz); 1518 if (!buf) 1519 return -ENOMEM; 1520 struct ext4_extent_header *ext_block; 1521 struct ext4_extent *extent; 1522 int i = -1; 1523 ext_block = 1524 ext4fs_get_extent_block(ext4fs_root, buf, 1525 (struct ext4_extent_header *) 1526 inode->b.blocks.dir_blocks, 1527 fileblock, log2_blksz); 1528 if (!ext_block) { 1529 printf("invalid extent block\n"); 1530 free(buf); 1531 return -EINVAL; 1532 } 1533 1534 extent = (struct ext4_extent *)(ext_block + 1); 1535 1536 do { 1537 i++; 1538 if (i >= le16_to_cpu(ext_block->eh_entries)) 1539 break; 1540 } while (fileblock >= le32_to_cpu(extent[i].ee_block)); 1541 if (--i >= 0) { 1542 fileblock -= le32_to_cpu(extent[i].ee_block); 1543 if (fileblock >= le16_to_cpu(extent[i].ee_len)) { 1544 free(buf); 1545 return 0; 1546 } 1547 1548 start = le16_to_cpu(extent[i].ee_start_hi); 1549 start = (start << 32) + 1550 le32_to_cpu(extent[i].ee_start_lo); 1551 free(buf); 1552 return fileblock + start; 1553 } 1554 1555 printf("Extent Error\n"); 1556 free(buf); 1557 return -1; 1558 } 1559 1560 /* Direct blocks. */ 1561 if (fileblock < INDIRECT_BLOCKS) 1562 blknr = __le32_to_cpu(inode->b.blocks.dir_blocks[fileblock]); 1563 1564 /* Indirect. */ 1565 else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4))) { 1566 if (ext4fs_indir1_block == NULL) { 1567 ext4fs_indir1_block = zalloc(blksz); 1568 if (ext4fs_indir1_block == NULL) { 1569 printf("** SI ext2fs read block (indir 1)" 1570 "malloc failed. **\n"); 1571 return -1; 1572 } 1573 ext4fs_indir1_size = blksz; 1574 ext4fs_indir1_blkno = -1; 1575 } 1576 if (blksz != ext4fs_indir1_size) { 1577 free(ext4fs_indir1_block); 1578 ext4fs_indir1_block = NULL; 1579 ext4fs_indir1_size = 0; 1580 ext4fs_indir1_blkno = -1; 1581 ext4fs_indir1_block = zalloc(blksz); 1582 if (ext4fs_indir1_block == NULL) { 1583 printf("** SI ext2fs read block (indir 1):" 1584 "malloc failed. **\n"); 1585 return -1; 1586 } 1587 ext4fs_indir1_size = blksz; 1588 } 1589 if ((__le32_to_cpu(inode->b.blocks.indir_block) << 1590 log2_blksz) != ext4fs_indir1_blkno) { 1591 status = 1592 ext4fs_devread((lbaint_t)__le32_to_cpu 1593 (inode->b.blocks. 1594 indir_block) << log2_blksz, 0, 1595 blksz, (char *)ext4fs_indir1_block); 1596 if (status == 0) { 1597 printf("** SI ext2fs read block (indir 1)" 1598 "failed. **\n"); 1599 return 0; 1600 } 1601 ext4fs_indir1_blkno = 1602 __le32_to_cpu(inode->b.blocks. 1603 indir_block) << log2_blksz; 1604 } 1605 blknr = __le32_to_cpu(ext4fs_indir1_block 1606 [fileblock - INDIRECT_BLOCKS]); 1607 } 1608 /* Double indirect. */ 1609 else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4 * 1610 (blksz / 4 + 1)))) { 1611 1612 long int perblock = blksz / 4; 1613 long int rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4); 1614 1615 if (ext4fs_indir1_block == NULL) { 1616 ext4fs_indir1_block = zalloc(blksz); 1617 if (ext4fs_indir1_block == NULL) { 1618 printf("** DI ext2fs read block (indir 2 1)" 1619 "malloc failed. **\n"); 1620 return -1; 1621 } 1622 ext4fs_indir1_size = blksz; 1623 ext4fs_indir1_blkno = -1; 1624 } 1625 if (blksz != ext4fs_indir1_size) { 1626 free(ext4fs_indir1_block); 1627 ext4fs_indir1_block = NULL; 1628 ext4fs_indir1_size = 0; 1629 ext4fs_indir1_blkno = -1; 1630 ext4fs_indir1_block = zalloc(blksz); 1631 if (ext4fs_indir1_block == NULL) { 1632 printf("** DI ext2fs read block (indir 2 1)" 1633 "malloc failed. **\n"); 1634 return -1; 1635 } 1636 ext4fs_indir1_size = blksz; 1637 } 1638 if ((__le32_to_cpu(inode->b.blocks.double_indir_block) << 1639 log2_blksz) != ext4fs_indir1_blkno) { 1640 status = 1641 ext4fs_devread((lbaint_t)__le32_to_cpu 1642 (inode->b.blocks. 1643 double_indir_block) << log2_blksz, 1644 0, blksz, 1645 (char *)ext4fs_indir1_block); 1646 if (status == 0) { 1647 printf("** DI ext2fs read block (indir 2 1)" 1648 "failed. **\n"); 1649 return -1; 1650 } 1651 ext4fs_indir1_blkno = 1652 __le32_to_cpu(inode->b.blocks.double_indir_block) << 1653 log2_blksz; 1654 } 1655 1656 if (ext4fs_indir2_block == NULL) { 1657 ext4fs_indir2_block = zalloc(blksz); 1658 if (ext4fs_indir2_block == NULL) { 1659 printf("** DI ext2fs read block (indir 2 2)" 1660 "malloc failed. **\n"); 1661 return -1; 1662 } 1663 ext4fs_indir2_size = blksz; 1664 ext4fs_indir2_blkno = -1; 1665 } 1666 if (blksz != ext4fs_indir2_size) { 1667 free(ext4fs_indir2_block); 1668 ext4fs_indir2_block = NULL; 1669 ext4fs_indir2_size = 0; 1670 ext4fs_indir2_blkno = -1; 1671 ext4fs_indir2_block = zalloc(blksz); 1672 if (ext4fs_indir2_block == NULL) { 1673 printf("** DI ext2fs read block (indir 2 2)" 1674 "malloc failed. **\n"); 1675 return -1; 1676 } 1677 ext4fs_indir2_size = blksz; 1678 } 1679 if ((__le32_to_cpu(ext4fs_indir1_block[rblock / perblock]) << 1680 log2_blksz) != ext4fs_indir2_blkno) { 1681 status = ext4fs_devread((lbaint_t)__le32_to_cpu 1682 (ext4fs_indir1_block 1683 [rblock / 1684 perblock]) << log2_blksz, 0, 1685 blksz, 1686 (char *)ext4fs_indir2_block); 1687 if (status == 0) { 1688 printf("** DI ext2fs read block (indir 2 2)" 1689 "failed. **\n"); 1690 return -1; 1691 } 1692 ext4fs_indir2_blkno = 1693 __le32_to_cpu(ext4fs_indir1_block[rblock 1694 / 1695 perblock]) << 1696 log2_blksz; 1697 } 1698 blknr = __le32_to_cpu(ext4fs_indir2_block[rblock % perblock]); 1699 } 1700 /* Tripple indirect. */ 1701 else { 1702 rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4 + 1703 (blksz / 4 * blksz / 4)); 1704 perblock_child = blksz / 4; 1705 perblock_parent = ((blksz / 4) * (blksz / 4)); 1706 1707 if (ext4fs_indir1_block == NULL) { 1708 ext4fs_indir1_block = zalloc(blksz); 1709 if (ext4fs_indir1_block == NULL) { 1710 printf("** TI ext2fs read block (indir 2 1)" 1711 "malloc failed. **\n"); 1712 return -1; 1713 } 1714 ext4fs_indir1_size = blksz; 1715 ext4fs_indir1_blkno = -1; 1716 } 1717 if (blksz != ext4fs_indir1_size) { 1718 free(ext4fs_indir1_block); 1719 ext4fs_indir1_block = NULL; 1720 ext4fs_indir1_size = 0; 1721 ext4fs_indir1_blkno = -1; 1722 ext4fs_indir1_block = zalloc(blksz); 1723 if (ext4fs_indir1_block == NULL) { 1724 printf("** TI ext2fs read block (indir 2 1)" 1725 "malloc failed. **\n"); 1726 return -1; 1727 } 1728 ext4fs_indir1_size = blksz; 1729 } 1730 if ((__le32_to_cpu(inode->b.blocks.triple_indir_block) << 1731 log2_blksz) != ext4fs_indir1_blkno) { 1732 status = ext4fs_devread 1733 ((lbaint_t) 1734 __le32_to_cpu(inode->b.blocks.triple_indir_block) 1735 << log2_blksz, 0, blksz, 1736 (char *)ext4fs_indir1_block); 1737 if (status == 0) { 1738 printf("** TI ext2fs read block (indir 2 1)" 1739 "failed. **\n"); 1740 return -1; 1741 } 1742 ext4fs_indir1_blkno = 1743 __le32_to_cpu(inode->b.blocks.triple_indir_block) << 1744 log2_blksz; 1745 } 1746 1747 if (ext4fs_indir2_block == NULL) { 1748 ext4fs_indir2_block = zalloc(blksz); 1749 if (ext4fs_indir2_block == NULL) { 1750 printf("** TI ext2fs read block (indir 2 2)" 1751 "malloc failed. **\n"); 1752 return -1; 1753 } 1754 ext4fs_indir2_size = blksz; 1755 ext4fs_indir2_blkno = -1; 1756 } 1757 if (blksz != ext4fs_indir2_size) { 1758 free(ext4fs_indir2_block); 1759 ext4fs_indir2_block = NULL; 1760 ext4fs_indir2_size = 0; 1761 ext4fs_indir2_blkno = -1; 1762 ext4fs_indir2_block = zalloc(blksz); 1763 if (ext4fs_indir2_block == NULL) { 1764 printf("** TI ext2fs read block (indir 2 2)" 1765 "malloc failed. **\n"); 1766 return -1; 1767 } 1768 ext4fs_indir2_size = blksz; 1769 } 1770 if ((__le32_to_cpu(ext4fs_indir1_block[rblock / 1771 perblock_parent]) << 1772 log2_blksz) 1773 != ext4fs_indir2_blkno) { 1774 status = ext4fs_devread((lbaint_t)__le32_to_cpu 1775 (ext4fs_indir1_block 1776 [rblock / 1777 perblock_parent]) << 1778 log2_blksz, 0, blksz, 1779 (char *)ext4fs_indir2_block); 1780 if (status == 0) { 1781 printf("** TI ext2fs read block (indir 2 2)" 1782 "failed. **\n"); 1783 return -1; 1784 } 1785 ext4fs_indir2_blkno = 1786 __le32_to_cpu(ext4fs_indir1_block[rblock / 1787 perblock_parent]) 1788 << log2_blksz; 1789 } 1790 1791 if (ext4fs_indir3_block == NULL) { 1792 ext4fs_indir3_block = zalloc(blksz); 1793 if (ext4fs_indir3_block == NULL) { 1794 printf("** TI ext2fs read block (indir 2 2)" 1795 "malloc failed. **\n"); 1796 return -1; 1797 } 1798 ext4fs_indir3_size = blksz; 1799 ext4fs_indir3_blkno = -1; 1800 } 1801 if (blksz != ext4fs_indir3_size) { 1802 free(ext4fs_indir3_block); 1803 ext4fs_indir3_block = NULL; 1804 ext4fs_indir3_size = 0; 1805 ext4fs_indir3_blkno = -1; 1806 ext4fs_indir3_block = zalloc(blksz); 1807 if (ext4fs_indir3_block == NULL) { 1808 printf("** TI ext2fs read block (indir 2 2)" 1809 "malloc failed. **\n"); 1810 return -1; 1811 } 1812 ext4fs_indir3_size = blksz; 1813 } 1814 if ((__le32_to_cpu(ext4fs_indir2_block[rblock 1815 / 1816 perblock_child]) << 1817 log2_blksz) != ext4fs_indir3_blkno) { 1818 status = 1819 ext4fs_devread((lbaint_t)__le32_to_cpu 1820 (ext4fs_indir2_block 1821 [(rblock / perblock_child) 1822 % (blksz / 4)]) << log2_blksz, 0, 1823 blksz, (char *)ext4fs_indir3_block); 1824 if (status == 0) { 1825 printf("** TI ext2fs read block (indir 2 2)" 1826 "failed. **\n"); 1827 return -1; 1828 } 1829 ext4fs_indir3_blkno = 1830 __le32_to_cpu(ext4fs_indir2_block[(rblock / 1831 perblock_child) % 1832 (blksz / 1833 4)]) << 1834 log2_blksz; 1835 } 1836 1837 blknr = __le32_to_cpu(ext4fs_indir3_block 1838 [rblock % perblock_child]); 1839 } 1840 debug("read_allocated_block %ld\n", blknr); 1841 1842 return blknr; 1843 } 1844 1845 /** 1846 * ext4fs_reinit_global() - Reinitialize values of ext4 write implementation's 1847 * global pointers 1848 * 1849 * This function assures that for a file with the same name but different size 1850 * the sequential store on the ext4 filesystem will be correct. 1851 * 1852 * In this function the global data, responsible for internal representation 1853 * of the ext4 data are initialized to the reset state. Without this, during 1854 * replacement of the smaller file with the bigger truncation of new file was 1855 * performed. 1856 */ 1857 void ext4fs_reinit_global(void) 1858 { 1859 if (ext4fs_indir1_block != NULL) { 1860 free(ext4fs_indir1_block); 1861 ext4fs_indir1_block = NULL; 1862 ext4fs_indir1_size = 0; 1863 ext4fs_indir1_blkno = -1; 1864 } 1865 if (ext4fs_indir2_block != NULL) { 1866 free(ext4fs_indir2_block); 1867 ext4fs_indir2_block = NULL; 1868 ext4fs_indir2_size = 0; 1869 ext4fs_indir2_blkno = -1; 1870 } 1871 if (ext4fs_indir3_block != NULL) { 1872 free(ext4fs_indir3_block); 1873 ext4fs_indir3_block = NULL; 1874 ext4fs_indir3_size = 0; 1875 ext4fs_indir3_blkno = -1; 1876 } 1877 } 1878 void ext4fs_close(void) 1879 { 1880 if ((ext4fs_file != NULL) && (ext4fs_root != NULL)) { 1881 ext4fs_free_node(ext4fs_file, &ext4fs_root->diropen); 1882 ext4fs_file = NULL; 1883 } 1884 if (ext4fs_root != NULL) { 1885 free(ext4fs_root); 1886 ext4fs_root = NULL; 1887 } 1888 1889 ext4fs_reinit_global(); 1890 } 1891 1892 int ext4fs_iterate_dir(struct ext2fs_node *dir, char *name, 1893 struct ext2fs_node **fnode, int *ftype) 1894 { 1895 unsigned int fpos = 0; 1896 int status; 1897 loff_t actread; 1898 struct ext2fs_node *diro = (struct ext2fs_node *) dir; 1899 1900 #ifdef DEBUG 1901 if (name != NULL) 1902 printf("Iterate dir %s\n", name); 1903 #endif /* of DEBUG */ 1904 if (!diro->inode_read) { 1905 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode); 1906 if (status == 0) 1907 return 0; 1908 } 1909 /* Search the file. */ 1910 while (fpos < __le32_to_cpu(diro->inode.size)) { 1911 struct ext2_dirent dirent; 1912 1913 status = ext4fs_read_file(diro, fpos, 1914 sizeof(struct ext2_dirent), 1915 (char *)&dirent, &actread); 1916 if (status < 0) 1917 return 0; 1918 1919 if (dirent.direntlen == 0) { 1920 printf("Failed to iterate over directory %s\n", name); 1921 return 0; 1922 } 1923 1924 if (dirent.namelen != 0) { 1925 char filename[dirent.namelen + 1]; 1926 struct ext2fs_node *fdiro; 1927 int type = FILETYPE_UNKNOWN; 1928 1929 status = ext4fs_read_file(diro, 1930 fpos + 1931 sizeof(struct ext2_dirent), 1932 dirent.namelen, filename, 1933 &actread); 1934 if (status < 0) 1935 return 0; 1936 1937 fdiro = zalloc(sizeof(struct ext2fs_node)); 1938 if (!fdiro) 1939 return 0; 1940 1941 fdiro->data = diro->data; 1942 fdiro->ino = __le32_to_cpu(dirent.inode); 1943 1944 filename[dirent.namelen] = '\0'; 1945 1946 if (dirent.filetype != FILETYPE_UNKNOWN) { 1947 fdiro->inode_read = 0; 1948 1949 if (dirent.filetype == FILETYPE_DIRECTORY) 1950 type = FILETYPE_DIRECTORY; 1951 else if (dirent.filetype == FILETYPE_SYMLINK) 1952 type = FILETYPE_SYMLINK; 1953 else if (dirent.filetype == FILETYPE_REG) 1954 type = FILETYPE_REG; 1955 } else { 1956 status = ext4fs_read_inode(diro->data, 1957 __le32_to_cpu 1958 (dirent.inode), 1959 &fdiro->inode); 1960 if (status == 0) { 1961 free(fdiro); 1962 return 0; 1963 } 1964 fdiro->inode_read = 1; 1965 1966 if ((__le16_to_cpu(fdiro->inode.mode) & 1967 FILETYPE_INO_MASK) == 1968 FILETYPE_INO_DIRECTORY) { 1969 type = FILETYPE_DIRECTORY; 1970 } else if ((__le16_to_cpu(fdiro->inode.mode) 1971 & FILETYPE_INO_MASK) == 1972 FILETYPE_INO_SYMLINK) { 1973 type = FILETYPE_SYMLINK; 1974 } else if ((__le16_to_cpu(fdiro->inode.mode) 1975 & FILETYPE_INO_MASK) == 1976 FILETYPE_INO_REG) { 1977 type = FILETYPE_REG; 1978 } 1979 } 1980 #ifdef DEBUG 1981 printf("iterate >%s<\n", filename); 1982 #endif /* of DEBUG */ 1983 if ((name != NULL) && (fnode != NULL) 1984 && (ftype != NULL)) { 1985 if (strcmp(filename, name) == 0) { 1986 *ftype = type; 1987 *fnode = fdiro; 1988 return 1; 1989 } 1990 } else { 1991 if (fdiro->inode_read == 0) { 1992 status = ext4fs_read_inode(diro->data, 1993 __le32_to_cpu( 1994 dirent.inode), 1995 &fdiro->inode); 1996 if (status == 0) { 1997 free(fdiro); 1998 return 0; 1999 } 2000 fdiro->inode_read = 1; 2001 } 2002 switch (type) { 2003 case FILETYPE_DIRECTORY: 2004 printf("<DIR> "); 2005 break; 2006 case FILETYPE_SYMLINK: 2007 printf("<SYM> "); 2008 break; 2009 case FILETYPE_REG: 2010 printf(" "); 2011 break; 2012 default: 2013 printf("< ? > "); 2014 break; 2015 } 2016 printf("%10u %s\n", 2017 __le32_to_cpu(fdiro->inode.size), 2018 filename); 2019 } 2020 free(fdiro); 2021 } 2022 fpos += __le16_to_cpu(dirent.direntlen); 2023 } 2024 return 0; 2025 } 2026 2027 static char *ext4fs_read_symlink(struct ext2fs_node *node) 2028 { 2029 char *symlink; 2030 struct ext2fs_node *diro = node; 2031 int status; 2032 loff_t actread; 2033 2034 if (!diro->inode_read) { 2035 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode); 2036 if (status == 0) 2037 return 0; 2038 } 2039 symlink = zalloc(__le32_to_cpu(diro->inode.size) + 1); 2040 if (!symlink) 2041 return 0; 2042 2043 if (__le32_to_cpu(diro->inode.size) < sizeof(diro->inode.b.symlink)) { 2044 strncpy(symlink, diro->inode.b.symlink, 2045 __le32_to_cpu(diro->inode.size)); 2046 } else { 2047 status = ext4fs_read_file(diro, 0, 2048 __le32_to_cpu(diro->inode.size), 2049 symlink, &actread); 2050 if ((status < 0) || (actread == 0)) { 2051 free(symlink); 2052 return 0; 2053 } 2054 } 2055 symlink[__le32_to_cpu(diro->inode.size)] = '\0'; 2056 return symlink; 2057 } 2058 2059 static int ext4fs_find_file1(const char *currpath, 2060 struct ext2fs_node *currroot, 2061 struct ext2fs_node **currfound, int *foundtype) 2062 { 2063 char fpath[strlen(currpath) + 1]; 2064 char *name = fpath; 2065 char *next; 2066 int status; 2067 int type = FILETYPE_DIRECTORY; 2068 struct ext2fs_node *currnode = currroot; 2069 struct ext2fs_node *oldnode = currroot; 2070 2071 strncpy(fpath, currpath, strlen(currpath) + 1); 2072 2073 /* Remove all leading slashes. */ 2074 while (*name == '/') 2075 name++; 2076 2077 if (!*name) { 2078 *currfound = currnode; 2079 return 1; 2080 } 2081 2082 for (;;) { 2083 int found; 2084 2085 /* Extract the actual part from the pathname. */ 2086 next = strchr(name, '/'); 2087 if (next) { 2088 /* Remove all leading slashes. */ 2089 while (*next == '/') 2090 *(next++) = '\0'; 2091 } 2092 2093 if (type != FILETYPE_DIRECTORY) { 2094 ext4fs_free_node(currnode, currroot); 2095 return 0; 2096 } 2097 2098 oldnode = currnode; 2099 2100 /* Iterate over the directory. */ 2101 found = ext4fs_iterate_dir(currnode, name, &currnode, &type); 2102 if (found == 0) 2103 return 0; 2104 2105 if (found == -1) 2106 break; 2107 2108 /* Read in the symlink and follow it. */ 2109 if (type == FILETYPE_SYMLINK) { 2110 char *symlink; 2111 2112 /* Test if the symlink does not loop. */ 2113 if (++symlinknest == 8) { 2114 ext4fs_free_node(currnode, currroot); 2115 ext4fs_free_node(oldnode, currroot); 2116 return 0; 2117 } 2118 2119 symlink = ext4fs_read_symlink(currnode); 2120 ext4fs_free_node(currnode, currroot); 2121 2122 if (!symlink) { 2123 ext4fs_free_node(oldnode, currroot); 2124 return 0; 2125 } 2126 2127 debug("Got symlink >%s<\n", symlink); 2128 2129 if (symlink[0] == '/') { 2130 ext4fs_free_node(oldnode, currroot); 2131 oldnode = &ext4fs_root->diropen; 2132 } 2133 2134 /* Lookup the node the symlink points to. */ 2135 status = ext4fs_find_file1(symlink, oldnode, 2136 &currnode, &type); 2137 2138 free(symlink); 2139 2140 if (status == 0) { 2141 ext4fs_free_node(oldnode, currroot); 2142 return 0; 2143 } 2144 } 2145 2146 ext4fs_free_node(oldnode, currroot); 2147 2148 /* Found the node! */ 2149 if (!next || *next == '\0') { 2150 *currfound = currnode; 2151 *foundtype = type; 2152 return 1; 2153 } 2154 name = next; 2155 } 2156 return -1; 2157 } 2158 2159 int ext4fs_find_file(const char *path, struct ext2fs_node *rootnode, 2160 struct ext2fs_node **foundnode, int expecttype) 2161 { 2162 int status; 2163 int foundtype = FILETYPE_DIRECTORY; 2164 2165 symlinknest = 0; 2166 if (!path) 2167 return 0; 2168 2169 status = ext4fs_find_file1(path, rootnode, foundnode, &foundtype); 2170 if (status == 0) 2171 return 0; 2172 2173 /* Check if the node that was found was of the expected type. */ 2174 if ((expecttype == FILETYPE_REG) && (foundtype != expecttype)) 2175 return 0; 2176 else if ((expecttype == FILETYPE_DIRECTORY) 2177 && (foundtype != expecttype)) 2178 return 0; 2179 2180 return 1; 2181 } 2182 2183 int ext4fs_open(const char *filename, loff_t *len) 2184 { 2185 struct ext2fs_node *fdiro = NULL; 2186 int status; 2187 2188 if (ext4fs_root == NULL) 2189 return -1; 2190 2191 ext4fs_file = NULL; 2192 status = ext4fs_find_file(filename, &ext4fs_root->diropen, &fdiro, 2193 FILETYPE_REG); 2194 if (status == 0) 2195 goto fail; 2196 2197 if (!fdiro->inode_read) { 2198 status = ext4fs_read_inode(fdiro->data, fdiro->ino, 2199 &fdiro->inode); 2200 if (status == 0) 2201 goto fail; 2202 } 2203 *len = __le32_to_cpu(fdiro->inode.size); 2204 ext4fs_file = fdiro; 2205 2206 return 0; 2207 fail: 2208 ext4fs_free_node(fdiro, &ext4fs_root->diropen); 2209 2210 return -1; 2211 } 2212 2213 int ext4fs_mount(unsigned part_length) 2214 { 2215 struct ext2_data *data; 2216 int status; 2217 struct ext_filesystem *fs = get_fs(); 2218 data = zalloc(SUPERBLOCK_SIZE); 2219 if (!data) 2220 return 0; 2221 2222 /* Read the superblock. */ 2223 status = ext4_read_superblock((char *)&data->sblock); 2224 2225 if (status == 0) 2226 goto fail; 2227 2228 /* Make sure this is an ext2 filesystem. */ 2229 if (__le16_to_cpu(data->sblock.magic) != EXT2_MAGIC) 2230 goto fail; 2231 2232 if (__le32_to_cpu(data->sblock.revision_level == 0)) 2233 fs->inodesz = 128; 2234 else 2235 fs->inodesz = __le16_to_cpu(data->sblock.inode_size); 2236 2237 debug("EXT2 rev %d, inode_size %d\n", 2238 __le32_to_cpu(data->sblock.revision_level), fs->inodesz); 2239 2240 data->diropen.data = data; 2241 data->diropen.ino = 2; 2242 data->diropen.inode_read = 1; 2243 data->inode = &data->diropen.inode; 2244 2245 status = ext4fs_read_inode(data, 2, data->inode); 2246 if (status == 0) 2247 goto fail; 2248 2249 ext4fs_root = data; 2250 2251 return 1; 2252 fail: 2253 printf("Failed to mount ext2 filesystem...\n"); 2254 free(data); 2255 ext4fs_root = NULL; 2256 2257 return 0; 2258 } 2259