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 __le32 *ext4fs_indir1_block; 37 int ext4fs_indir1_size; 38 int ext4fs_indir1_blkno = -1; 39 __le32 *ext4fs_indir2_block; 40 int ext4fs_indir2_size; 41 int ext4fs_indir2_blkno = -1; 42 43 __le32 *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 static inline void ext4fs_sb_free_inodes_dec(struct ext2_sblock *sb) 51 { 52 sb->free_inodes = cpu_to_le32(le32_to_cpu(sb->free_inodes) - 1); 53 } 54 55 static inline void ext4fs_sb_free_blocks_dec(struct ext2_sblock *sb) 56 { 57 sb->free_blocks = cpu_to_le32(le32_to_cpu(sb->free_blocks) - 1); 58 } 59 60 static inline void ext4fs_bg_free_inodes_dec(struct ext2_block_group *bg) 61 { 62 bg->free_inodes = cpu_to_le16(le16_to_cpu(bg->free_inodes) - 1); 63 } 64 65 static inline void ext4fs_bg_free_blocks_dec(struct ext2_block_group *bg) 66 { 67 bg->free_blocks = cpu_to_le16(le16_to_cpu(bg->free_blocks) - 1); 68 } 69 70 static inline void ext4fs_bg_itable_unused_dec(struct ext2_block_group *bg) 71 { 72 bg->bg_itable_unused = cpu_to_le16(le16_to_cpu(bg->bg_itable_unused) - 1); 73 } 74 75 uint32_t ext4fs_div_roundup(uint32_t size, uint32_t n) 76 { 77 uint32_t res = size / n; 78 if (res * n != size) 79 res++; 80 81 return res; 82 } 83 84 void put_ext4(uint64_t off, void *buf, uint32_t size) 85 { 86 uint64_t startblock; 87 uint64_t remainder; 88 unsigned char *temp_ptr = NULL; 89 struct ext_filesystem *fs = get_fs(); 90 int log2blksz = fs->dev_desc->log2blksz; 91 ALLOC_CACHE_ALIGN_BUFFER(unsigned char, sec_buf, fs->dev_desc->blksz); 92 93 startblock = off >> log2blksz; 94 startblock += part_offset; 95 remainder = off & (uint64_t)(fs->dev_desc->blksz - 1); 96 97 if (fs->dev_desc == NULL) 98 return; 99 100 if ((startblock + (size >> log2blksz)) > 101 (part_offset + fs->total_sect)) { 102 printf("part_offset is " LBAFU "\n", part_offset); 103 printf("total_sector is %" PRIu64 "\n", fs->total_sect); 104 printf("error: overflow occurs\n"); 105 return; 106 } 107 108 if (remainder) { 109 blk_dread(fs->dev_desc, startblock, 1, sec_buf); 110 temp_ptr = sec_buf; 111 memcpy((temp_ptr + remainder), (unsigned char *)buf, size); 112 blk_dwrite(fs->dev_desc, startblock, 1, sec_buf); 113 } else { 114 if (size >> log2blksz != 0) { 115 blk_dwrite(fs->dev_desc, startblock, size >> log2blksz, 116 (unsigned long *)buf); 117 } else { 118 blk_dread(fs->dev_desc, startblock, 1, sec_buf); 119 temp_ptr = sec_buf; 120 memcpy(temp_ptr, buf, size); 121 blk_dwrite(fs->dev_desc, startblock, 1, 122 (unsigned long *)sec_buf); 123 } 124 } 125 } 126 127 static int _get_new_inode_no(unsigned char *buffer) 128 { 129 struct ext_filesystem *fs = get_fs(); 130 unsigned char input; 131 int operand, status; 132 int count = 1; 133 int j = 0; 134 135 /* get the blocksize of the filesystem */ 136 unsigned char *ptr = buffer; 137 while (*ptr == 255) { 138 ptr++; 139 count += 8; 140 if (count > le32_to_cpu(ext4fs_root->sblock.inodes_per_group)) 141 return -1; 142 } 143 144 for (j = 0; j < fs->blksz; j++) { 145 input = *ptr; 146 int i = 0; 147 while (i <= 7) { 148 operand = 1 << i; 149 status = input & operand; 150 if (status) { 151 i++; 152 count++; 153 } else { 154 *ptr |= operand; 155 return count; 156 } 157 } 158 ptr = ptr + 1; 159 } 160 161 return -1; 162 } 163 164 static int _get_new_blk_no(unsigned char *buffer) 165 { 166 int operand; 167 int count = 0; 168 int i; 169 unsigned char *ptr = buffer; 170 struct ext_filesystem *fs = get_fs(); 171 172 while (*ptr == 255) { 173 ptr++; 174 count += 8; 175 if (count == (fs->blksz * 8)) 176 return -1; 177 } 178 179 if (fs->blksz == 1024) 180 count += 1; 181 182 for (i = 0; i <= 7; i++) { 183 operand = 1 << i; 184 if (*ptr & operand) { 185 count++; 186 } else { 187 *ptr |= operand; 188 return count; 189 } 190 } 191 192 return -1; 193 } 194 195 int ext4fs_set_block_bmap(long int blockno, unsigned char *buffer, int index) 196 { 197 int i, remainder, status; 198 unsigned char *ptr = buffer; 199 unsigned char operand; 200 i = blockno / 8; 201 remainder = blockno % 8; 202 int blocksize = EXT2_BLOCK_SIZE(ext4fs_root); 203 204 i = i - (index * blocksize); 205 if (blocksize != 1024) { 206 ptr = ptr + i; 207 operand = 1 << remainder; 208 status = *ptr & operand; 209 if (status) 210 return -1; 211 212 *ptr = *ptr | operand; 213 return 0; 214 } else { 215 if (remainder == 0) { 216 ptr = ptr + i - 1; 217 operand = (1 << 7); 218 } else { 219 ptr = ptr + i; 220 operand = (1 << (remainder - 1)); 221 } 222 status = *ptr & operand; 223 if (status) 224 return -1; 225 226 *ptr = *ptr | operand; 227 return 0; 228 } 229 } 230 231 void ext4fs_reset_block_bmap(long int blockno, unsigned char *buffer, int index) 232 { 233 int i, remainder, status; 234 unsigned char *ptr = buffer; 235 unsigned char operand; 236 i = blockno / 8; 237 remainder = blockno % 8; 238 int blocksize = EXT2_BLOCK_SIZE(ext4fs_root); 239 240 i = i - (index * blocksize); 241 if (blocksize != 1024) { 242 ptr = ptr + i; 243 operand = (1 << remainder); 244 status = *ptr & operand; 245 if (status) 246 *ptr = *ptr & ~(operand); 247 } else { 248 if (remainder == 0) { 249 ptr = ptr + i - 1; 250 operand = (1 << 7); 251 } else { 252 ptr = ptr + i; 253 operand = (1 << (remainder - 1)); 254 } 255 status = *ptr & operand; 256 if (status) 257 *ptr = *ptr & ~(operand); 258 } 259 } 260 261 int ext4fs_set_inode_bmap(int inode_no, unsigned char *buffer, int index) 262 { 263 int i, remainder, status; 264 unsigned char *ptr = buffer; 265 unsigned char operand; 266 267 inode_no -= (index * le32_to_cpu(ext4fs_root->sblock.inodes_per_group)); 268 i = inode_no / 8; 269 remainder = inode_no % 8; 270 if (remainder == 0) { 271 ptr = ptr + i - 1; 272 operand = (1 << 7); 273 } else { 274 ptr = ptr + i; 275 operand = (1 << (remainder - 1)); 276 } 277 status = *ptr & operand; 278 if (status) 279 return -1; 280 281 *ptr = *ptr | operand; 282 283 return 0; 284 } 285 286 void ext4fs_reset_inode_bmap(int inode_no, unsigned char *buffer, int index) 287 { 288 int i, remainder, status; 289 unsigned char *ptr = buffer; 290 unsigned char operand; 291 292 inode_no -= (index * le32_to_cpu(ext4fs_root->sblock.inodes_per_group)); 293 i = inode_no / 8; 294 remainder = inode_no % 8; 295 if (remainder == 0) { 296 ptr = ptr + i - 1; 297 operand = (1 << 7); 298 } else { 299 ptr = ptr + i; 300 operand = (1 << (remainder - 1)); 301 } 302 status = *ptr & operand; 303 if (status) 304 *ptr = *ptr & ~(operand); 305 } 306 307 uint16_t ext4fs_checksum_update(uint32_t i) 308 { 309 struct ext2_block_group *desc; 310 struct ext_filesystem *fs = get_fs(); 311 uint16_t crc = 0; 312 __le32 le32_i = cpu_to_le32(i); 313 314 desc = (struct ext2_block_group *)&fs->bgd[i]; 315 if (le32_to_cpu(fs->sb->feature_ro_compat) & EXT4_FEATURE_RO_COMPAT_GDT_CSUM) { 316 int offset = offsetof(struct ext2_block_group, bg_checksum); 317 318 crc = ext2fs_crc16(~0, fs->sb->unique_id, 319 sizeof(fs->sb->unique_id)); 320 crc = ext2fs_crc16(crc, &le32_i, sizeof(le32_i)); 321 crc = ext2fs_crc16(crc, desc, offset); 322 offset += sizeof(desc->bg_checksum); /* skip checksum */ 323 assert(offset == sizeof(*desc)); 324 } 325 326 return crc; 327 } 328 329 static int check_void_in_dentry(struct ext2_dirent *dir, char *filename) 330 { 331 int dentry_length; 332 int sizeof_void_space; 333 int new_entry_byte_reqd; 334 short padding_factor = 0; 335 336 if (dir->namelen % 4 != 0) 337 padding_factor = 4 - (dir->namelen % 4); 338 339 dentry_length = sizeof(struct ext2_dirent) + 340 dir->namelen + padding_factor; 341 sizeof_void_space = le16_to_cpu(dir->direntlen) - dentry_length; 342 if (sizeof_void_space == 0) 343 return 0; 344 345 padding_factor = 0; 346 if (strlen(filename) % 4 != 0) 347 padding_factor = 4 - (strlen(filename) % 4); 348 349 new_entry_byte_reqd = strlen(filename) + 350 sizeof(struct ext2_dirent) + padding_factor; 351 if (sizeof_void_space >= new_entry_byte_reqd) { 352 dir->direntlen = cpu_to_le16(dentry_length); 353 return sizeof_void_space; 354 } 355 356 return 0; 357 } 358 359 int ext4fs_update_parent_dentry(char *filename, int file_type) 360 { 361 unsigned int *zero_buffer = NULL; 362 char *root_first_block_buffer = NULL; 363 int blk_idx; 364 long int first_block_no_of_root = 0; 365 int totalbytes = 0; 366 unsigned int new_entry_byte_reqd; 367 int sizeof_void_space = 0; 368 int templength = 0; 369 int inodeno = -1; 370 int status; 371 struct ext_filesystem *fs = get_fs(); 372 /* directory entry */ 373 struct ext2_dirent *dir; 374 char *temp_dir = NULL; 375 uint32_t new_blk_no; 376 uint32_t new_size; 377 uint32_t new_blockcnt; 378 uint32_t directory_blocks; 379 380 zero_buffer = zalloc(fs->blksz); 381 if (!zero_buffer) { 382 printf("No Memory\n"); 383 return -1; 384 } 385 root_first_block_buffer = zalloc(fs->blksz); 386 if (!root_first_block_buffer) { 387 free(zero_buffer); 388 printf("No Memory\n"); 389 return -1; 390 } 391 new_entry_byte_reqd = ROUND(strlen(filename) + 392 sizeof(struct ext2_dirent), 4); 393 restart: 394 directory_blocks = le32_to_cpu(g_parent_inode->size) >> 395 LOG2_BLOCK_SIZE(ext4fs_root); 396 blk_idx = directory_blocks - 1; 397 398 restart_read: 399 /* read the block no allocated to a file */ 400 first_block_no_of_root = read_allocated_block(g_parent_inode, blk_idx); 401 if (first_block_no_of_root <= 0) 402 goto fail; 403 404 status = ext4fs_devread((lbaint_t)first_block_no_of_root 405 * fs->sect_perblk, 406 0, fs->blksz, root_first_block_buffer); 407 if (status == 0) 408 goto fail; 409 410 if (ext4fs_log_journal(root_first_block_buffer, first_block_no_of_root)) 411 goto fail; 412 dir = (struct ext2_dirent *)root_first_block_buffer; 413 totalbytes = 0; 414 415 while (le16_to_cpu(dir->direntlen) > 0) { 416 unsigned short used_len = ROUND(dir->namelen + 417 sizeof(struct ext2_dirent), 4); 418 419 /* last entry of block */ 420 if (fs->blksz - totalbytes == le16_to_cpu(dir->direntlen)) { 421 422 /* check if new entry fits */ 423 if ((used_len + new_entry_byte_reqd) <= 424 le16_to_cpu(dir->direntlen)) { 425 dir->direntlen = cpu_to_le16(used_len); 426 break; 427 } else { 428 if (blk_idx > 0) { 429 printf("Block full, trying previous\n"); 430 blk_idx--; 431 goto restart_read; 432 } 433 printf("All blocks full: Allocate new\n"); 434 435 if (le32_to_cpu(g_parent_inode->flags) & 436 EXT4_EXTENTS_FL) { 437 printf("Directory uses extents\n"); 438 goto fail; 439 } 440 if (directory_blocks >= INDIRECT_BLOCKS) { 441 printf("Directory exceeds limit\n"); 442 goto fail; 443 } 444 new_blk_no = ext4fs_get_new_blk_no(); 445 if (new_blk_no == -1) { 446 printf("no block left to assign\n"); 447 goto fail; 448 } 449 put_ext4((uint64_t)new_blk_no * fs->blksz, zero_buffer, fs->blksz); 450 g_parent_inode->b.blocks. 451 dir_blocks[directory_blocks] = 452 cpu_to_le32(new_blk_no); 453 454 new_size = le32_to_cpu(g_parent_inode->size); 455 new_size += fs->blksz; 456 g_parent_inode->size = cpu_to_le32(new_size); 457 458 new_blockcnt = le32_to_cpu(g_parent_inode->blockcnt); 459 new_blockcnt += fs->sect_perblk; 460 g_parent_inode->blockcnt = cpu_to_le32(new_blockcnt); 461 462 if (ext4fs_put_metadata 463 (root_first_block_buffer, 464 first_block_no_of_root)) 465 goto fail; 466 goto restart; 467 } 468 } 469 470 templength = le16_to_cpu(dir->direntlen); 471 totalbytes = totalbytes + templength; 472 sizeof_void_space = check_void_in_dentry(dir, filename); 473 if (sizeof_void_space) 474 break; 475 476 dir = (struct ext2_dirent *)((char *)dir + templength); 477 } 478 479 /* make a pointer ready for creating next directory entry */ 480 templength = le16_to_cpu(dir->direntlen); 481 totalbytes = totalbytes + templength; 482 dir = (struct ext2_dirent *)((char *)dir + templength); 483 484 /* get the next available inode number */ 485 inodeno = ext4fs_get_new_inode_no(); 486 if (inodeno == -1) { 487 printf("no inode left to assign\n"); 488 goto fail; 489 } 490 dir->inode = cpu_to_le32(inodeno); 491 if (sizeof_void_space) 492 dir->direntlen = cpu_to_le16(sizeof_void_space); 493 else 494 dir->direntlen = cpu_to_le16(fs->blksz - totalbytes); 495 496 dir->namelen = strlen(filename); 497 dir->filetype = FILETYPE_REG; /* regular file */ 498 temp_dir = (char *)dir; 499 temp_dir = temp_dir + sizeof(struct ext2_dirent); 500 memcpy(temp_dir, filename, strlen(filename)); 501 502 /* update or write the 1st block of root inode */ 503 if (ext4fs_put_metadata(root_first_block_buffer, 504 first_block_no_of_root)) 505 goto fail; 506 507 fail: 508 free(zero_buffer); 509 free(root_first_block_buffer); 510 511 return inodeno; 512 } 513 514 static int search_dir(struct ext2_inode *parent_inode, char *dirname) 515 { 516 int status; 517 int inodeno = 0; 518 int offset; 519 int blk_idx; 520 long int blknr; 521 char *block_buffer = NULL; 522 struct ext2_dirent *dir = NULL; 523 struct ext_filesystem *fs = get_fs(); 524 uint32_t directory_blocks; 525 char *direntname; 526 527 directory_blocks = le32_to_cpu(parent_inode->size) >> 528 LOG2_BLOCK_SIZE(ext4fs_root); 529 530 block_buffer = zalloc(fs->blksz); 531 if (!block_buffer) 532 goto fail; 533 534 /* get the block no allocated to a file */ 535 for (blk_idx = 0; blk_idx < directory_blocks; blk_idx++) { 536 blknr = read_allocated_block(parent_inode, blk_idx); 537 if (blknr <= 0) 538 goto fail; 539 540 /* read the directory block */ 541 status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 542 0, fs->blksz, (char *)block_buffer); 543 if (status == 0) 544 goto fail; 545 546 offset = 0; 547 do { 548 dir = (struct ext2_dirent *)(block_buffer + offset); 549 direntname = (char*)(dir) + sizeof(struct ext2_dirent); 550 551 int direntlen = le16_to_cpu(dir->direntlen); 552 if (direntlen < sizeof(struct ext2_dirent)) 553 break; 554 555 if (dir->inode && (strlen(dirname) == dir->namelen) && 556 (strncmp(dirname, direntname, dir->namelen) == 0)) { 557 inodeno = le32_to_cpu(dir->inode); 558 break; 559 } 560 561 offset += direntlen; 562 563 } while (offset < fs->blksz); 564 565 if (inodeno > 0) { 566 free(block_buffer); 567 return inodeno; 568 } 569 } 570 571 fail: 572 free(block_buffer); 573 574 return -1; 575 } 576 577 static int find_dir_depth(char *dirname) 578 { 579 char *token = strtok(dirname, "/"); 580 int count = 0; 581 while (token != NULL) { 582 token = strtok(NULL, "/"); 583 count++; 584 } 585 return count + 1 + 1; 586 /* 587 * for example for string /home/temp 588 * depth=home(1)+temp(1)+1 extra for NULL; 589 * so count is 4; 590 */ 591 } 592 593 static int parse_path(char **arr, char *dirname) 594 { 595 char *token = strtok(dirname, "/"); 596 int i = 0; 597 598 /* add root */ 599 arr[i] = zalloc(strlen("/") + 1); 600 if (!arr[i]) 601 return -ENOMEM; 602 memcpy(arr[i++], "/", strlen("/")); 603 604 /* add each path entry after root */ 605 while (token != NULL) { 606 arr[i] = zalloc(strlen(token) + 1); 607 if (!arr[i]) 608 return -ENOMEM; 609 memcpy(arr[i++], token, strlen(token)); 610 token = strtok(NULL, "/"); 611 } 612 arr[i] = NULL; 613 614 return 0; 615 } 616 617 int ext4fs_iget(int inode_no, struct ext2_inode *inode) 618 { 619 if (ext4fs_read_inode(ext4fs_root, inode_no, inode) == 0) 620 return -1; 621 622 return 0; 623 } 624 625 /* 626 * Function: ext4fs_get_parent_inode_num 627 * Return Value: inode Number of the parent directory of file/Directory to be 628 * created 629 * dirname : Input parmater, input path name of the file/directory to be created 630 * dname : Output parameter, to be filled with the name of the directory 631 * extracted from dirname 632 */ 633 int ext4fs_get_parent_inode_num(const char *dirname, char *dname, int flags) 634 { 635 int i; 636 int depth = 0; 637 int matched_inode_no; 638 int result_inode_no = -1; 639 char **ptr = NULL; 640 char *depth_dirname = NULL; 641 char *parse_dirname = NULL; 642 struct ext2_inode *parent_inode = NULL; 643 struct ext2_inode *first_inode = NULL; 644 struct ext2_inode temp_inode; 645 646 if (*dirname != '/') { 647 printf("Please supply Absolute path\n"); 648 return -1; 649 } 650 651 /* TODO: input validation make equivalent to linux */ 652 depth_dirname = zalloc(strlen(dirname) + 1); 653 if (!depth_dirname) 654 return -ENOMEM; 655 656 memcpy(depth_dirname, dirname, strlen(dirname)); 657 depth = find_dir_depth(depth_dirname); 658 parse_dirname = zalloc(strlen(dirname) + 1); 659 if (!parse_dirname) 660 goto fail; 661 memcpy(parse_dirname, dirname, strlen(dirname)); 662 663 /* allocate memory for each directory level */ 664 ptr = zalloc((depth) * sizeof(char *)); 665 if (!ptr) 666 goto fail; 667 if (parse_path(ptr, parse_dirname)) 668 goto fail; 669 parent_inode = zalloc(sizeof(struct ext2_inode)); 670 if (!parent_inode) 671 goto fail; 672 first_inode = zalloc(sizeof(struct ext2_inode)); 673 if (!first_inode) 674 goto fail; 675 memcpy(parent_inode, ext4fs_root->inode, sizeof(struct ext2_inode)); 676 memcpy(first_inode, parent_inode, sizeof(struct ext2_inode)); 677 if (flags & F_FILE) 678 result_inode_no = EXT2_ROOT_INO; 679 for (i = 1; i < depth; i++) { 680 matched_inode_no = search_dir(parent_inode, ptr[i]); 681 if (matched_inode_no == -1) { 682 if (ptr[i + 1] == NULL && i == 1) { 683 result_inode_no = EXT2_ROOT_INO; 684 goto end; 685 } else { 686 if (ptr[i + 1] == NULL) 687 break; 688 printf("Invalid path\n"); 689 result_inode_no = -1; 690 goto fail; 691 } 692 } else { 693 if (ptr[i + 1] != NULL) { 694 memset(parent_inode, '\0', 695 sizeof(struct ext2_inode)); 696 if (ext4fs_iget(matched_inode_no, 697 parent_inode)) { 698 result_inode_no = -1; 699 goto fail; 700 } 701 result_inode_no = matched_inode_no; 702 } else { 703 break; 704 } 705 } 706 } 707 708 end: 709 if (i == 1) 710 matched_inode_no = search_dir(first_inode, ptr[i]); 711 else 712 matched_inode_no = search_dir(parent_inode, ptr[i]); 713 714 if (matched_inode_no != -1) { 715 ext4fs_iget(matched_inode_no, &temp_inode); 716 if (le16_to_cpu(temp_inode.mode) & S_IFDIR) { 717 printf("It is a Directory\n"); 718 result_inode_no = -1; 719 goto fail; 720 } 721 } 722 723 if (strlen(ptr[i]) > 256) { 724 result_inode_no = -1; 725 goto fail; 726 } 727 memcpy(dname, ptr[i], strlen(ptr[i])); 728 729 fail: 730 free(depth_dirname); 731 free(parse_dirname); 732 for (i = 0; i < depth; i++) { 733 if (!ptr[i]) 734 break; 735 free(ptr[i]); 736 } 737 free(ptr); 738 free(parent_inode); 739 free(first_inode); 740 741 return result_inode_no; 742 } 743 744 static int unlink_filename(char *filename, unsigned int blknr) 745 { 746 int totalbytes = 0; 747 int templength = 0; 748 int status, inodeno; 749 int found = 0; 750 char *root_first_block_buffer = NULL; 751 struct ext2_dirent *dir = NULL; 752 struct ext2_dirent *previous_dir = NULL; 753 char *ptr = NULL; 754 struct ext_filesystem *fs = get_fs(); 755 int ret = -1; 756 757 /* get the first block of root */ 758 root_first_block_buffer = zalloc(fs->blksz); 759 if (!root_first_block_buffer) 760 return -ENOMEM; 761 status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 0, 762 fs->blksz, root_first_block_buffer); 763 if (status == 0) 764 goto fail; 765 766 if (ext4fs_log_journal(root_first_block_buffer, blknr)) 767 goto fail; 768 dir = (struct ext2_dirent *)root_first_block_buffer; 769 ptr = (char *)dir; 770 totalbytes = 0; 771 while (le16_to_cpu(dir->direntlen) >= 0) { 772 /* 773 * blocksize-totalbytes because last 774 * directory length i.e., *dir->direntlen 775 * is free availble space in the block that 776 * means it is a last entry of directory entry 777 */ 778 if (dir->inode && (strlen(filename) == dir->namelen) && 779 (strncmp(ptr + sizeof(struct ext2_dirent), 780 filename, dir->namelen) == 0)) { 781 printf("file found, deleting\n"); 782 inodeno = le32_to_cpu(dir->inode); 783 if (previous_dir) { 784 uint16_t new_len; 785 new_len = le16_to_cpu(previous_dir->direntlen); 786 new_len += le16_to_cpu(dir->direntlen); 787 previous_dir->direntlen = cpu_to_le16(new_len); 788 } else { 789 dir->inode = 0; 790 } 791 found = 1; 792 break; 793 } 794 795 if (fs->blksz - totalbytes == le16_to_cpu(dir->direntlen)) 796 break; 797 798 /* traversing the each directory entry */ 799 templength = le16_to_cpu(dir->direntlen); 800 totalbytes = totalbytes + templength; 801 previous_dir = dir; 802 dir = (struct ext2_dirent *)((char *)dir + templength); 803 ptr = (char *)dir; 804 } 805 806 807 if (found == 1) { 808 if (ext4fs_put_metadata(root_first_block_buffer, blknr)) 809 goto fail; 810 ret = inodeno; 811 } 812 fail: 813 free(root_first_block_buffer); 814 815 return ret; 816 } 817 818 int ext4fs_filename_unlink(char *filename) 819 { 820 int blk_idx; 821 long int blknr = -1; 822 int inodeno = -1; 823 uint32_t directory_blocks; 824 825 directory_blocks = le32_to_cpu(g_parent_inode->size) >> 826 LOG2_BLOCK_SIZE(ext4fs_root); 827 828 /* read the block no allocated to a file */ 829 for (blk_idx = 0; blk_idx < directory_blocks; blk_idx++) { 830 blknr = read_allocated_block(g_parent_inode, blk_idx); 831 if (blknr <= 0) 832 break; 833 inodeno = unlink_filename(filename, blknr); 834 if (inodeno != -1) 835 return inodeno; 836 } 837 838 return -1; 839 } 840 841 uint32_t ext4fs_get_new_blk_no(void) 842 { 843 short i; 844 short status; 845 int remainder; 846 unsigned int bg_idx; 847 static int prev_bg_bitmap_index = -1; 848 unsigned int blk_per_grp = le32_to_cpu(ext4fs_root->sblock.blocks_per_group); 849 struct ext_filesystem *fs = get_fs(); 850 char *journal_buffer = zalloc(fs->blksz); 851 char *zero_buffer = zalloc(fs->blksz); 852 if (!journal_buffer || !zero_buffer) 853 goto fail; 854 struct ext2_block_group *bgd = (struct ext2_block_group *)fs->gdtable; 855 856 if (fs->first_pass_bbmap == 0) { 857 for (i = 0; i < fs->no_blkgrp; i++) { 858 if (le16_to_cpu(bgd[i].free_blocks)) { 859 if (le16_to_cpu(bgd[i].bg_flags) & EXT4_BG_BLOCK_UNINIT) { 860 uint16_t new_flags; 861 put_ext4((uint64_t)le32_to_cpu(bgd[i].block_id) * fs->blksz, 862 zero_buffer, fs->blksz); 863 new_flags = le16_to_cpu(bgd[i].bg_flags) & ~EXT4_BG_BLOCK_UNINIT; 864 bgd[i].bg_flags = cpu_to_le16(new_flags); 865 memcpy(fs->blk_bmaps[i], zero_buffer, 866 fs->blksz); 867 } 868 fs->curr_blkno = 869 _get_new_blk_no(fs->blk_bmaps[i]); 870 if (fs->curr_blkno == -1) 871 /* if block bitmap is completely fill */ 872 continue; 873 fs->curr_blkno = fs->curr_blkno + 874 (i * fs->blksz * 8); 875 fs->first_pass_bbmap++; 876 ext4fs_bg_free_blocks_dec(&bgd[i]); 877 ext4fs_sb_free_blocks_dec(fs->sb); 878 status = ext4fs_devread( 879 (lbaint_t)le32_to_cpu(bgd[i].block_id) * 880 fs->sect_perblk, 0, 881 fs->blksz, 882 journal_buffer); 883 if (status == 0) 884 goto fail; 885 if (ext4fs_log_journal(journal_buffer, 886 le32_to_cpu(bgd[i].block_id))) 887 goto fail; 888 goto success; 889 } else { 890 debug("no space left on block group %d\n", i); 891 } 892 } 893 894 goto fail; 895 } else { 896 fs->curr_blkno++; 897 restart: 898 /* get the blockbitmap index respective to blockno */ 899 bg_idx = fs->curr_blkno / blk_per_grp; 900 if (fs->blksz == 1024) { 901 remainder = fs->curr_blkno % blk_per_grp; 902 if (!remainder) 903 bg_idx--; 904 } 905 906 /* 907 * To skip completely filled block group bitmaps 908 * Optimize the block allocation 909 */ 910 if (bg_idx >= fs->no_blkgrp) 911 goto fail; 912 913 if (bgd[bg_idx].free_blocks == 0) { 914 debug("block group %u is full. Skipping\n", bg_idx); 915 fs->curr_blkno = (bg_idx + 1) * blk_per_grp; 916 if (fs->blksz == 1024) 917 fs->curr_blkno += 1; 918 goto restart; 919 } 920 921 if (le16_to_cpu(bgd[bg_idx].bg_flags) & EXT4_BG_BLOCK_UNINIT) { 922 uint16_t new_flags; 923 put_ext4((uint64_t)le32_to_cpu(bgd[bg_idx].block_id) * fs->blksz, 924 zero_buffer, fs->blksz); 925 memcpy(fs->blk_bmaps[bg_idx], zero_buffer, fs->blksz); 926 new_flags = le16_to_cpu(bgd[bg_idx].bg_flags) & ~EXT4_BG_BLOCK_UNINIT; 927 bgd[bg_idx].bg_flags = cpu_to_le16(new_flags); 928 } 929 930 if (ext4fs_set_block_bmap(fs->curr_blkno, fs->blk_bmaps[bg_idx], 931 bg_idx) != 0) { 932 debug("going for restart for the block no %ld %u\n", 933 fs->curr_blkno, bg_idx); 934 fs->curr_blkno++; 935 goto restart; 936 } 937 938 /* journal backup */ 939 if (prev_bg_bitmap_index != bg_idx) { 940 status = ext4fs_devread( 941 (lbaint_t)le32_to_cpu(bgd[bg_idx].block_id) 942 * fs->sect_perblk, 943 0, fs->blksz, journal_buffer); 944 if (status == 0) 945 goto fail; 946 if (ext4fs_log_journal(journal_buffer, 947 le32_to_cpu(bgd[bg_idx].block_id))) 948 goto fail; 949 950 prev_bg_bitmap_index = bg_idx; 951 } 952 ext4fs_bg_free_blocks_dec(&bgd[bg_idx]); 953 ext4fs_sb_free_blocks_dec(fs->sb); 954 goto success; 955 } 956 success: 957 free(journal_buffer); 958 free(zero_buffer); 959 960 return fs->curr_blkno; 961 fail: 962 free(journal_buffer); 963 free(zero_buffer); 964 965 return -1; 966 } 967 968 int ext4fs_get_new_inode_no(void) 969 { 970 short i; 971 short status; 972 unsigned int ibmap_idx; 973 static int prev_inode_bitmap_index = -1; 974 unsigned int inodes_per_grp = le32_to_cpu(ext4fs_root->sblock.inodes_per_group); 975 struct ext_filesystem *fs = get_fs(); 976 char *journal_buffer = zalloc(fs->blksz); 977 char *zero_buffer = zalloc(fs->blksz); 978 if (!journal_buffer || !zero_buffer) 979 goto fail; 980 struct ext2_block_group *bgd = (struct ext2_block_group *)fs->gdtable; 981 int has_gdt_chksum = le32_to_cpu(fs->sb->feature_ro_compat) & 982 EXT4_FEATURE_RO_COMPAT_GDT_CSUM ? 1 : 0; 983 984 if (fs->first_pass_ibmap == 0) { 985 for (i = 0; i < fs->no_blkgrp; i++) { 986 if (bgd[i].free_inodes) { 987 if (has_gdt_chksum) 988 bgd[i].bg_itable_unused = 989 bgd[i].free_inodes; 990 if (le16_to_cpu(bgd[i].bg_flags) & EXT4_BG_INODE_UNINIT) { 991 int new_flags; 992 put_ext4((uint64_t)le32_to_cpu(bgd[i].inode_id) * fs->blksz, 993 zero_buffer, fs->blksz); 994 new_flags = le16_to_cpu(bgd[i].bg_flags) & ~EXT4_BG_INODE_UNINIT; 995 bgd[i].bg_flags = cpu_to_le16(new_flags); 996 memcpy(fs->inode_bmaps[i], 997 zero_buffer, fs->blksz); 998 } 999 fs->curr_inode_no = 1000 _get_new_inode_no(fs->inode_bmaps[i]); 1001 if (fs->curr_inode_no == -1) 1002 /* if block bitmap is completely fill */ 1003 continue; 1004 fs->curr_inode_no = fs->curr_inode_no + 1005 (i * inodes_per_grp); 1006 fs->first_pass_ibmap++; 1007 ext4fs_bg_free_inodes_dec(&bgd[i]); 1008 if (has_gdt_chksum) 1009 ext4fs_bg_itable_unused_dec(&bgd[i]); 1010 ext4fs_sb_free_inodes_dec(fs->sb); 1011 status = ext4fs_devread( 1012 (lbaint_t)le32_to_cpu(bgd[i].inode_id) * 1013 fs->sect_perblk, 0, 1014 fs->blksz, 1015 journal_buffer); 1016 if (status == 0) 1017 goto fail; 1018 if (ext4fs_log_journal(journal_buffer, 1019 le32_to_cpu(bgd[i].inode_id))) 1020 goto fail; 1021 goto success; 1022 } else 1023 debug("no inode left on block group %d\n", i); 1024 } 1025 goto fail; 1026 } else { 1027 restart: 1028 fs->curr_inode_no++; 1029 /* get the blockbitmap index respective to blockno */ 1030 ibmap_idx = fs->curr_inode_no / inodes_per_grp; 1031 if (le16_to_cpu(bgd[ibmap_idx].bg_flags) & EXT4_BG_INODE_UNINIT) { 1032 int new_flags; 1033 put_ext4((uint64_t)le32_to_cpu(bgd[ibmap_idx].inode_id) * fs->blksz, 1034 zero_buffer, fs->blksz); 1035 new_flags = le16_to_cpu(bgd[ibmap_idx].bg_flags) & ~EXT4_BG_INODE_UNINIT; 1036 bgd[ibmap_idx].bg_flags = cpu_to_le16(new_flags); 1037 memcpy(fs->inode_bmaps[ibmap_idx], zero_buffer, 1038 fs->blksz); 1039 } 1040 1041 if (ext4fs_set_inode_bmap(fs->curr_inode_no, 1042 fs->inode_bmaps[ibmap_idx], 1043 ibmap_idx) != 0) { 1044 debug("going for restart for the block no %d %u\n", 1045 fs->curr_inode_no, ibmap_idx); 1046 goto restart; 1047 } 1048 1049 /* journal backup */ 1050 if (prev_inode_bitmap_index != ibmap_idx) { 1051 memset(journal_buffer, '\0', fs->blksz); 1052 status = ext4fs_devread( 1053 (lbaint_t)le32_to_cpu(bgd[ibmap_idx].inode_id) 1054 * fs->sect_perblk, 1055 0, fs->blksz, journal_buffer); 1056 if (status == 0) 1057 goto fail; 1058 if (ext4fs_log_journal(journal_buffer, 1059 le32_to_cpu(bgd[ibmap_idx].inode_id))) 1060 goto fail; 1061 prev_inode_bitmap_index = ibmap_idx; 1062 } 1063 ext4fs_bg_free_inodes_dec(&bgd[ibmap_idx]); 1064 if (has_gdt_chksum) 1065 bgd[ibmap_idx].bg_itable_unused = 1066 bgd[ibmap_idx].free_inodes; 1067 ext4fs_sb_free_inodes_dec(fs->sb); 1068 goto success; 1069 } 1070 1071 success: 1072 free(journal_buffer); 1073 free(zero_buffer); 1074 1075 return fs->curr_inode_no; 1076 fail: 1077 free(journal_buffer); 1078 free(zero_buffer); 1079 1080 return -1; 1081 1082 } 1083 1084 1085 static void alloc_single_indirect_block(struct ext2_inode *file_inode, 1086 unsigned int *total_remaining_blocks, 1087 unsigned int *no_blks_reqd) 1088 { 1089 short i; 1090 short status; 1091 long int actual_block_no; 1092 long int si_blockno; 1093 /* si :single indirect */ 1094 __le32 *si_buffer = NULL; 1095 __le32 *si_start_addr = NULL; 1096 struct ext_filesystem *fs = get_fs(); 1097 1098 if (*total_remaining_blocks != 0) { 1099 si_buffer = zalloc(fs->blksz); 1100 if (!si_buffer) { 1101 printf("No Memory\n"); 1102 return; 1103 } 1104 si_start_addr = si_buffer; 1105 si_blockno = ext4fs_get_new_blk_no(); 1106 if (si_blockno == -1) { 1107 printf("no block left to assign\n"); 1108 goto fail; 1109 } 1110 (*no_blks_reqd)++; 1111 debug("SIPB %ld: %u\n", si_blockno, *total_remaining_blocks); 1112 1113 status = ext4fs_devread((lbaint_t)si_blockno * fs->sect_perblk, 1114 0, fs->blksz, (char *)si_buffer); 1115 memset(si_buffer, '\0', fs->blksz); 1116 if (status == 0) 1117 goto fail; 1118 1119 for (i = 0; i < (fs->blksz / sizeof(int)); i++) { 1120 actual_block_no = ext4fs_get_new_blk_no(); 1121 if (actual_block_no == -1) { 1122 printf("no block left to assign\n"); 1123 goto fail; 1124 } 1125 *si_buffer = cpu_to_le32(actual_block_no); 1126 debug("SIAB %u: %u\n", *si_buffer, 1127 *total_remaining_blocks); 1128 1129 si_buffer++; 1130 (*total_remaining_blocks)--; 1131 if (*total_remaining_blocks == 0) 1132 break; 1133 } 1134 1135 /* write the block to disk */ 1136 put_ext4(((uint64_t) ((uint64_t)si_blockno * (uint64_t)fs->blksz)), 1137 si_start_addr, fs->blksz); 1138 file_inode->b.blocks.indir_block = cpu_to_le32(si_blockno); 1139 } 1140 fail: 1141 free(si_start_addr); 1142 } 1143 1144 static void alloc_double_indirect_block(struct ext2_inode *file_inode, 1145 unsigned int *total_remaining_blocks, 1146 unsigned int *no_blks_reqd) 1147 { 1148 short i; 1149 short j; 1150 short status; 1151 long int actual_block_no; 1152 /* di:double indirect */ 1153 long int di_blockno_parent; 1154 long int di_blockno_child; 1155 __le32 *di_parent_buffer = NULL; 1156 __le32 *di_child_buff = NULL; 1157 __le32 *di_block_start_addr = NULL; 1158 __le32 *di_child_buff_start = NULL; 1159 struct ext_filesystem *fs = get_fs(); 1160 1161 if (*total_remaining_blocks != 0) { 1162 /* double indirect parent block connecting to inode */ 1163 di_blockno_parent = ext4fs_get_new_blk_no(); 1164 if (di_blockno_parent == -1) { 1165 printf("no block left to assign\n"); 1166 goto fail; 1167 } 1168 di_parent_buffer = zalloc(fs->blksz); 1169 if (!di_parent_buffer) 1170 goto fail; 1171 1172 di_block_start_addr = di_parent_buffer; 1173 (*no_blks_reqd)++; 1174 debug("DIPB %ld: %u\n", di_blockno_parent, 1175 *total_remaining_blocks); 1176 1177 status = ext4fs_devread((lbaint_t)di_blockno_parent * 1178 fs->sect_perblk, 0, 1179 fs->blksz, (char *)di_parent_buffer); 1180 1181 if (!status) { 1182 printf("%s: Device read error!\n", __func__); 1183 goto fail; 1184 } 1185 memset(di_parent_buffer, '\0', fs->blksz); 1186 1187 /* 1188 * start:for each double indirect parent 1189 * block create one more block 1190 */ 1191 for (i = 0; i < (fs->blksz / sizeof(int)); i++) { 1192 di_blockno_child = ext4fs_get_new_blk_no(); 1193 if (di_blockno_child == -1) { 1194 printf("no block left to assign\n"); 1195 goto fail; 1196 } 1197 di_child_buff = zalloc(fs->blksz); 1198 if (!di_child_buff) 1199 goto fail; 1200 1201 di_child_buff_start = di_child_buff; 1202 *di_parent_buffer = cpu_to_le32(di_blockno_child); 1203 di_parent_buffer++; 1204 (*no_blks_reqd)++; 1205 debug("DICB %ld: %u\n", di_blockno_child, 1206 *total_remaining_blocks); 1207 1208 status = ext4fs_devread((lbaint_t)di_blockno_child * 1209 fs->sect_perblk, 0, 1210 fs->blksz, 1211 (char *)di_child_buff); 1212 1213 if (!status) { 1214 printf("%s: Device read error!\n", __func__); 1215 goto fail; 1216 } 1217 memset(di_child_buff, '\0', fs->blksz); 1218 /* filling of actual datablocks for each child */ 1219 for (j = 0; j < (fs->blksz / sizeof(int)); j++) { 1220 actual_block_no = ext4fs_get_new_blk_no(); 1221 if (actual_block_no == -1) { 1222 printf("no block left to assign\n"); 1223 goto fail; 1224 } 1225 *di_child_buff = cpu_to_le32(actual_block_no); 1226 debug("DIAB %ld: %u\n", actual_block_no, 1227 *total_remaining_blocks); 1228 1229 di_child_buff++; 1230 (*total_remaining_blocks)--; 1231 if (*total_remaining_blocks == 0) 1232 break; 1233 } 1234 /* write the block table */ 1235 put_ext4(((uint64_t) ((uint64_t)di_blockno_child * (uint64_t)fs->blksz)), 1236 di_child_buff_start, fs->blksz); 1237 free(di_child_buff_start); 1238 di_child_buff_start = NULL; 1239 1240 if (*total_remaining_blocks == 0) 1241 break; 1242 } 1243 put_ext4(((uint64_t) ((uint64_t)di_blockno_parent * (uint64_t)fs->blksz)), 1244 di_block_start_addr, fs->blksz); 1245 file_inode->b.blocks.double_indir_block = cpu_to_le32(di_blockno_parent); 1246 } 1247 fail: 1248 free(di_block_start_addr); 1249 } 1250 1251 static void alloc_triple_indirect_block(struct ext2_inode *file_inode, 1252 unsigned int *total_remaining_blocks, 1253 unsigned int *no_blks_reqd) 1254 { 1255 short i; 1256 short j; 1257 short k; 1258 long int actual_block_no; 1259 /* ti: Triple Indirect */ 1260 long int ti_gp_blockno; 1261 long int ti_parent_blockno; 1262 long int ti_child_blockno; 1263 __le32 *ti_gp_buff = NULL; 1264 __le32 *ti_parent_buff = NULL; 1265 __le32 *ti_child_buff = NULL; 1266 __le32 *ti_gp_buff_start_addr = NULL; 1267 __le32 *ti_pbuff_start_addr = NULL; 1268 __le32 *ti_cbuff_start_addr = NULL; 1269 struct ext_filesystem *fs = get_fs(); 1270 if (*total_remaining_blocks != 0) { 1271 /* triple indirect grand parent block connecting to inode */ 1272 ti_gp_blockno = ext4fs_get_new_blk_no(); 1273 if (ti_gp_blockno == -1) { 1274 printf("no block left to assign\n"); 1275 return; 1276 } 1277 ti_gp_buff = zalloc(fs->blksz); 1278 if (!ti_gp_buff) 1279 return; 1280 1281 ti_gp_buff_start_addr = ti_gp_buff; 1282 (*no_blks_reqd)++; 1283 debug("TIGPB %ld: %u\n", ti_gp_blockno, 1284 *total_remaining_blocks); 1285 1286 /* for each 4 byte grand parent entry create one more block */ 1287 for (i = 0; i < (fs->blksz / sizeof(int)); i++) { 1288 ti_parent_blockno = ext4fs_get_new_blk_no(); 1289 if (ti_parent_blockno == -1) { 1290 printf("no block left to assign\n"); 1291 goto fail; 1292 } 1293 ti_parent_buff = zalloc(fs->blksz); 1294 if (!ti_parent_buff) 1295 goto fail; 1296 1297 ti_pbuff_start_addr = ti_parent_buff; 1298 *ti_gp_buff = cpu_to_le32(ti_parent_blockno); 1299 ti_gp_buff++; 1300 (*no_blks_reqd)++; 1301 debug("TIPB %ld: %u\n", ti_parent_blockno, 1302 *total_remaining_blocks); 1303 1304 /* for each 4 byte entry parent create one more block */ 1305 for (j = 0; j < (fs->blksz / sizeof(int)); j++) { 1306 ti_child_blockno = ext4fs_get_new_blk_no(); 1307 if (ti_child_blockno == -1) { 1308 printf("no block left assign\n"); 1309 goto fail1; 1310 } 1311 ti_child_buff = zalloc(fs->blksz); 1312 if (!ti_child_buff) 1313 goto fail1; 1314 1315 ti_cbuff_start_addr = ti_child_buff; 1316 *ti_parent_buff = cpu_to_le32(ti_child_blockno); 1317 ti_parent_buff++; 1318 (*no_blks_reqd)++; 1319 debug("TICB %ld: %u\n", ti_parent_blockno, 1320 *total_remaining_blocks); 1321 1322 /* fill actual datablocks for each child */ 1323 for (k = 0; k < (fs->blksz / sizeof(int)); 1324 k++) { 1325 actual_block_no = 1326 ext4fs_get_new_blk_no(); 1327 if (actual_block_no == -1) { 1328 printf("no block left\n"); 1329 free(ti_cbuff_start_addr); 1330 goto fail1; 1331 } 1332 *ti_child_buff = cpu_to_le32(actual_block_no); 1333 debug("TIAB %ld: %u\n", actual_block_no, 1334 *total_remaining_blocks); 1335 1336 ti_child_buff++; 1337 (*total_remaining_blocks)--; 1338 if (*total_remaining_blocks == 0) 1339 break; 1340 } 1341 /* write the child block */ 1342 put_ext4(((uint64_t) ((uint64_t)ti_child_blockno * 1343 (uint64_t)fs->blksz)), 1344 ti_cbuff_start_addr, fs->blksz); 1345 free(ti_cbuff_start_addr); 1346 1347 if (*total_remaining_blocks == 0) 1348 break; 1349 } 1350 /* write the parent block */ 1351 put_ext4(((uint64_t) ((uint64_t)ti_parent_blockno * (uint64_t)fs->blksz)), 1352 ti_pbuff_start_addr, fs->blksz); 1353 free(ti_pbuff_start_addr); 1354 1355 if (*total_remaining_blocks == 0) 1356 break; 1357 } 1358 /* write the grand parent block */ 1359 put_ext4(((uint64_t) ((uint64_t)ti_gp_blockno * (uint64_t)fs->blksz)), 1360 ti_gp_buff_start_addr, fs->blksz); 1361 file_inode->b.blocks.triple_indir_block = cpu_to_le32(ti_gp_blockno); 1362 free(ti_gp_buff_start_addr); 1363 return; 1364 } 1365 fail1: 1366 free(ti_pbuff_start_addr); 1367 fail: 1368 free(ti_gp_buff_start_addr); 1369 } 1370 1371 void ext4fs_allocate_blocks(struct ext2_inode *file_inode, 1372 unsigned int total_remaining_blocks, 1373 unsigned int *total_no_of_block) 1374 { 1375 short i; 1376 long int direct_blockno; 1377 unsigned int no_blks_reqd = 0; 1378 1379 /* allocation of direct blocks */ 1380 for (i = 0; total_remaining_blocks && i < INDIRECT_BLOCKS; i++) { 1381 direct_blockno = ext4fs_get_new_blk_no(); 1382 if (direct_blockno == -1) { 1383 printf("no block left to assign\n"); 1384 return; 1385 } 1386 file_inode->b.blocks.dir_blocks[i] = cpu_to_le32(direct_blockno); 1387 debug("DB %ld: %u\n", direct_blockno, total_remaining_blocks); 1388 1389 total_remaining_blocks--; 1390 } 1391 1392 alloc_single_indirect_block(file_inode, &total_remaining_blocks, 1393 &no_blks_reqd); 1394 alloc_double_indirect_block(file_inode, &total_remaining_blocks, 1395 &no_blks_reqd); 1396 alloc_triple_indirect_block(file_inode, &total_remaining_blocks, 1397 &no_blks_reqd); 1398 *total_no_of_block += no_blks_reqd; 1399 } 1400 1401 #endif 1402 1403 static struct ext4_extent_header *ext4fs_get_extent_block 1404 (struct ext2_data *data, char *buf, 1405 struct ext4_extent_header *ext_block, 1406 uint32_t fileblock, int log2_blksz) 1407 { 1408 struct ext4_extent_idx *index; 1409 unsigned long long block; 1410 int blksz = EXT2_BLOCK_SIZE(data); 1411 int i; 1412 1413 while (1) { 1414 index = (struct ext4_extent_idx *)(ext_block + 1); 1415 1416 if (le16_to_cpu(ext_block->eh_magic) != EXT4_EXT_MAGIC) 1417 return NULL; 1418 1419 if (ext_block->eh_depth == 0) 1420 return ext_block; 1421 i = -1; 1422 do { 1423 i++; 1424 if (i >= le16_to_cpu(ext_block->eh_entries)) 1425 break; 1426 } while (fileblock >= le32_to_cpu(index[i].ei_block)); 1427 1428 if (--i < 0) 1429 return NULL; 1430 1431 block = le16_to_cpu(index[i].ei_leaf_hi); 1432 block = (block << 32) + le32_to_cpu(index[i].ei_leaf_lo); 1433 1434 if (ext4fs_devread((lbaint_t)block << log2_blksz, 0, blksz, 1435 buf)) 1436 ext_block = (struct ext4_extent_header *)buf; 1437 else 1438 return NULL; 1439 } 1440 } 1441 1442 static int ext4fs_blockgroup 1443 (struct ext2_data *data, int group, struct ext2_block_group *blkgrp) 1444 { 1445 long int blkno; 1446 unsigned int blkoff, desc_per_blk; 1447 int log2blksz = get_fs()->dev_desc->log2blksz; 1448 1449 desc_per_blk = EXT2_BLOCK_SIZE(data) / sizeof(struct ext2_block_group); 1450 1451 blkno = le32_to_cpu(data->sblock.first_data_block) + 1 + 1452 group / desc_per_blk; 1453 blkoff = (group % desc_per_blk) * sizeof(struct ext2_block_group); 1454 1455 debug("ext4fs read %d group descriptor (blkno %ld blkoff %u)\n", 1456 group, blkno, blkoff); 1457 1458 return ext4fs_devread((lbaint_t)blkno << 1459 (LOG2_BLOCK_SIZE(data) - log2blksz), 1460 blkoff, sizeof(struct ext2_block_group), 1461 (char *)blkgrp); 1462 } 1463 1464 int ext4fs_read_inode(struct ext2_data *data, int ino, struct ext2_inode *inode) 1465 { 1466 struct ext2_block_group blkgrp; 1467 struct ext2_sblock *sblock = &data->sblock; 1468 struct ext_filesystem *fs = get_fs(); 1469 int log2blksz = get_fs()->dev_desc->log2blksz; 1470 int inodes_per_block, status; 1471 long int blkno; 1472 unsigned int blkoff; 1473 1474 /* It is easier to calculate if the first inode is 0. */ 1475 ino--; 1476 status = ext4fs_blockgroup(data, ino / le32_to_cpu 1477 (sblock->inodes_per_group), &blkgrp); 1478 if (status == 0) 1479 return 0; 1480 1481 inodes_per_block = EXT2_BLOCK_SIZE(data) / fs->inodesz; 1482 blkno = le32_to_cpu(blkgrp.inode_table_id) + 1483 (ino % le32_to_cpu(sblock->inodes_per_group)) / inodes_per_block; 1484 blkoff = (ino % inodes_per_block) * fs->inodesz; 1485 /* Read the inode. */ 1486 status = ext4fs_devread((lbaint_t)blkno << (LOG2_BLOCK_SIZE(data) - 1487 log2blksz), blkoff, 1488 sizeof(struct ext2_inode), (char *)inode); 1489 if (status == 0) 1490 return 0; 1491 1492 return 1; 1493 } 1494 1495 long int read_allocated_block(struct ext2_inode *inode, int fileblock) 1496 { 1497 long int blknr; 1498 int blksz; 1499 int log2_blksz; 1500 int status; 1501 long int rblock; 1502 long int perblock_parent; 1503 long int perblock_child; 1504 unsigned long long start; 1505 /* get the blocksize of the filesystem */ 1506 blksz = EXT2_BLOCK_SIZE(ext4fs_root); 1507 log2_blksz = LOG2_BLOCK_SIZE(ext4fs_root) 1508 - get_fs()->dev_desc->log2blksz; 1509 1510 if (le32_to_cpu(inode->flags) & EXT4_EXTENTS_FL) { 1511 char *buf = zalloc(blksz); 1512 if (!buf) 1513 return -ENOMEM; 1514 struct ext4_extent_header *ext_block; 1515 struct ext4_extent *extent; 1516 int i = -1; 1517 ext_block = 1518 ext4fs_get_extent_block(ext4fs_root, buf, 1519 (struct ext4_extent_header *) 1520 inode->b.blocks.dir_blocks, 1521 fileblock, log2_blksz); 1522 if (!ext_block) { 1523 printf("invalid extent block\n"); 1524 free(buf); 1525 return -EINVAL; 1526 } 1527 1528 extent = (struct ext4_extent *)(ext_block + 1); 1529 1530 do { 1531 i++; 1532 if (i >= le16_to_cpu(ext_block->eh_entries)) 1533 break; 1534 } while (fileblock >= le32_to_cpu(extent[i].ee_block)); 1535 if (--i >= 0) { 1536 fileblock -= le32_to_cpu(extent[i].ee_block); 1537 if (fileblock >= le16_to_cpu(extent[i].ee_len)) { 1538 free(buf); 1539 return 0; 1540 } 1541 1542 start = le16_to_cpu(extent[i].ee_start_hi); 1543 start = (start << 32) + 1544 le32_to_cpu(extent[i].ee_start_lo); 1545 free(buf); 1546 return fileblock + start; 1547 } 1548 1549 printf("Extent Error\n"); 1550 free(buf); 1551 return -1; 1552 } 1553 1554 /* Direct blocks. */ 1555 if (fileblock < INDIRECT_BLOCKS) 1556 blknr = le32_to_cpu(inode->b.blocks.dir_blocks[fileblock]); 1557 1558 /* Indirect. */ 1559 else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4))) { 1560 if (ext4fs_indir1_block == NULL) { 1561 ext4fs_indir1_block = zalloc(blksz); 1562 if (ext4fs_indir1_block == NULL) { 1563 printf("** SI ext2fs read block (indir 1)" 1564 "malloc failed. **\n"); 1565 return -1; 1566 } 1567 ext4fs_indir1_size = blksz; 1568 ext4fs_indir1_blkno = -1; 1569 } 1570 if (blksz != ext4fs_indir1_size) { 1571 free(ext4fs_indir1_block); 1572 ext4fs_indir1_block = NULL; 1573 ext4fs_indir1_size = 0; 1574 ext4fs_indir1_blkno = -1; 1575 ext4fs_indir1_block = zalloc(blksz); 1576 if (ext4fs_indir1_block == NULL) { 1577 printf("** SI ext2fs read block (indir 1):" 1578 "malloc failed. **\n"); 1579 return -1; 1580 } 1581 ext4fs_indir1_size = blksz; 1582 } 1583 if ((le32_to_cpu(inode->b.blocks.indir_block) << 1584 log2_blksz) != ext4fs_indir1_blkno) { 1585 status = 1586 ext4fs_devread((lbaint_t)le32_to_cpu 1587 (inode->b.blocks. 1588 indir_block) << log2_blksz, 0, 1589 blksz, (char *)ext4fs_indir1_block); 1590 if (status == 0) { 1591 printf("** SI ext2fs read block (indir 1)" 1592 "failed. **\n"); 1593 return -1; 1594 } 1595 ext4fs_indir1_blkno = 1596 le32_to_cpu(inode->b.blocks. 1597 indir_block) << log2_blksz; 1598 } 1599 blknr = le32_to_cpu(ext4fs_indir1_block 1600 [fileblock - INDIRECT_BLOCKS]); 1601 } 1602 /* Double indirect. */ 1603 else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4 * 1604 (blksz / 4 + 1)))) { 1605 1606 long int perblock = blksz / 4; 1607 long int rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4); 1608 1609 if (ext4fs_indir1_block == NULL) { 1610 ext4fs_indir1_block = zalloc(blksz); 1611 if (ext4fs_indir1_block == NULL) { 1612 printf("** DI ext2fs read block (indir 2 1)" 1613 "malloc failed. **\n"); 1614 return -1; 1615 } 1616 ext4fs_indir1_size = blksz; 1617 ext4fs_indir1_blkno = -1; 1618 } 1619 if (blksz != ext4fs_indir1_size) { 1620 free(ext4fs_indir1_block); 1621 ext4fs_indir1_block = NULL; 1622 ext4fs_indir1_size = 0; 1623 ext4fs_indir1_blkno = -1; 1624 ext4fs_indir1_block = zalloc(blksz); 1625 if (ext4fs_indir1_block == NULL) { 1626 printf("** DI ext2fs read block (indir 2 1)" 1627 "malloc failed. **\n"); 1628 return -1; 1629 } 1630 ext4fs_indir1_size = blksz; 1631 } 1632 if ((le32_to_cpu(inode->b.blocks.double_indir_block) << 1633 log2_blksz) != ext4fs_indir1_blkno) { 1634 status = 1635 ext4fs_devread((lbaint_t)le32_to_cpu 1636 (inode->b.blocks. 1637 double_indir_block) << log2_blksz, 1638 0, blksz, 1639 (char *)ext4fs_indir1_block); 1640 if (status == 0) { 1641 printf("** DI ext2fs read block (indir 2 1)" 1642 "failed. **\n"); 1643 return -1; 1644 } 1645 ext4fs_indir1_blkno = 1646 le32_to_cpu(inode->b.blocks.double_indir_block) << 1647 log2_blksz; 1648 } 1649 1650 if (ext4fs_indir2_block == NULL) { 1651 ext4fs_indir2_block = zalloc(blksz); 1652 if (ext4fs_indir2_block == NULL) { 1653 printf("** DI ext2fs read block (indir 2 2)" 1654 "malloc failed. **\n"); 1655 return -1; 1656 } 1657 ext4fs_indir2_size = blksz; 1658 ext4fs_indir2_blkno = -1; 1659 } 1660 if (blksz != ext4fs_indir2_size) { 1661 free(ext4fs_indir2_block); 1662 ext4fs_indir2_block = NULL; 1663 ext4fs_indir2_size = 0; 1664 ext4fs_indir2_blkno = -1; 1665 ext4fs_indir2_block = zalloc(blksz); 1666 if (ext4fs_indir2_block == NULL) { 1667 printf("** DI ext2fs read block (indir 2 2)" 1668 "malloc failed. **\n"); 1669 return -1; 1670 } 1671 ext4fs_indir2_size = blksz; 1672 } 1673 if ((le32_to_cpu(ext4fs_indir1_block[rblock / perblock]) << 1674 log2_blksz) != ext4fs_indir2_blkno) { 1675 status = ext4fs_devread((lbaint_t)le32_to_cpu 1676 (ext4fs_indir1_block 1677 [rblock / 1678 perblock]) << log2_blksz, 0, 1679 blksz, 1680 (char *)ext4fs_indir2_block); 1681 if (status == 0) { 1682 printf("** DI ext2fs read block (indir 2 2)" 1683 "failed. **\n"); 1684 return -1; 1685 } 1686 ext4fs_indir2_blkno = 1687 le32_to_cpu(ext4fs_indir1_block[rblock 1688 / 1689 perblock]) << 1690 log2_blksz; 1691 } 1692 blknr = le32_to_cpu(ext4fs_indir2_block[rblock % perblock]); 1693 } 1694 /* Tripple indirect. */ 1695 else { 1696 rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4 + 1697 (blksz / 4 * blksz / 4)); 1698 perblock_child = blksz / 4; 1699 perblock_parent = ((blksz / 4) * (blksz / 4)); 1700 1701 if (ext4fs_indir1_block == NULL) { 1702 ext4fs_indir1_block = zalloc(blksz); 1703 if (ext4fs_indir1_block == NULL) { 1704 printf("** TI ext2fs read block (indir 2 1)" 1705 "malloc failed. **\n"); 1706 return -1; 1707 } 1708 ext4fs_indir1_size = blksz; 1709 ext4fs_indir1_blkno = -1; 1710 } 1711 if (blksz != ext4fs_indir1_size) { 1712 free(ext4fs_indir1_block); 1713 ext4fs_indir1_block = NULL; 1714 ext4fs_indir1_size = 0; 1715 ext4fs_indir1_blkno = -1; 1716 ext4fs_indir1_block = zalloc(blksz); 1717 if (ext4fs_indir1_block == NULL) { 1718 printf("** TI ext2fs read block (indir 2 1)" 1719 "malloc failed. **\n"); 1720 return -1; 1721 } 1722 ext4fs_indir1_size = blksz; 1723 } 1724 if ((le32_to_cpu(inode->b.blocks.triple_indir_block) << 1725 log2_blksz) != ext4fs_indir1_blkno) { 1726 status = ext4fs_devread 1727 ((lbaint_t) 1728 le32_to_cpu(inode->b.blocks.triple_indir_block) 1729 << log2_blksz, 0, blksz, 1730 (char *)ext4fs_indir1_block); 1731 if (status == 0) { 1732 printf("** TI ext2fs read block (indir 2 1)" 1733 "failed. **\n"); 1734 return -1; 1735 } 1736 ext4fs_indir1_blkno = 1737 le32_to_cpu(inode->b.blocks.triple_indir_block) << 1738 log2_blksz; 1739 } 1740 1741 if (ext4fs_indir2_block == NULL) { 1742 ext4fs_indir2_block = zalloc(blksz); 1743 if (ext4fs_indir2_block == NULL) { 1744 printf("** TI ext2fs read block (indir 2 2)" 1745 "malloc failed. **\n"); 1746 return -1; 1747 } 1748 ext4fs_indir2_size = blksz; 1749 ext4fs_indir2_blkno = -1; 1750 } 1751 if (blksz != ext4fs_indir2_size) { 1752 free(ext4fs_indir2_block); 1753 ext4fs_indir2_block = NULL; 1754 ext4fs_indir2_size = 0; 1755 ext4fs_indir2_blkno = -1; 1756 ext4fs_indir2_block = zalloc(blksz); 1757 if (ext4fs_indir2_block == NULL) { 1758 printf("** TI ext2fs read block (indir 2 2)" 1759 "malloc failed. **\n"); 1760 return -1; 1761 } 1762 ext4fs_indir2_size = blksz; 1763 } 1764 if ((le32_to_cpu(ext4fs_indir1_block[rblock / 1765 perblock_parent]) << 1766 log2_blksz) 1767 != ext4fs_indir2_blkno) { 1768 status = ext4fs_devread((lbaint_t)le32_to_cpu 1769 (ext4fs_indir1_block 1770 [rblock / 1771 perblock_parent]) << 1772 log2_blksz, 0, blksz, 1773 (char *)ext4fs_indir2_block); 1774 if (status == 0) { 1775 printf("** TI ext2fs read block (indir 2 2)" 1776 "failed. **\n"); 1777 return -1; 1778 } 1779 ext4fs_indir2_blkno = 1780 le32_to_cpu(ext4fs_indir1_block[rblock / 1781 perblock_parent]) 1782 << log2_blksz; 1783 } 1784 1785 if (ext4fs_indir3_block == NULL) { 1786 ext4fs_indir3_block = zalloc(blksz); 1787 if (ext4fs_indir3_block == NULL) { 1788 printf("** TI ext2fs read block (indir 2 2)" 1789 "malloc failed. **\n"); 1790 return -1; 1791 } 1792 ext4fs_indir3_size = blksz; 1793 ext4fs_indir3_blkno = -1; 1794 } 1795 if (blksz != ext4fs_indir3_size) { 1796 free(ext4fs_indir3_block); 1797 ext4fs_indir3_block = NULL; 1798 ext4fs_indir3_size = 0; 1799 ext4fs_indir3_blkno = -1; 1800 ext4fs_indir3_block = zalloc(blksz); 1801 if (ext4fs_indir3_block == NULL) { 1802 printf("** TI ext2fs read block (indir 2 2)" 1803 "malloc failed. **\n"); 1804 return -1; 1805 } 1806 ext4fs_indir3_size = blksz; 1807 } 1808 if ((le32_to_cpu(ext4fs_indir2_block[rblock 1809 / 1810 perblock_child]) << 1811 log2_blksz) != ext4fs_indir3_blkno) { 1812 status = 1813 ext4fs_devread((lbaint_t)le32_to_cpu 1814 (ext4fs_indir2_block 1815 [(rblock / perblock_child) 1816 % (blksz / 4)]) << log2_blksz, 0, 1817 blksz, (char *)ext4fs_indir3_block); 1818 if (status == 0) { 1819 printf("** TI ext2fs read block (indir 2 2)" 1820 "failed. **\n"); 1821 return -1; 1822 } 1823 ext4fs_indir3_blkno = 1824 le32_to_cpu(ext4fs_indir2_block[(rblock / 1825 perblock_child) % 1826 (blksz / 1827 4)]) << 1828 log2_blksz; 1829 } 1830 1831 blknr = le32_to_cpu(ext4fs_indir3_block 1832 [rblock % perblock_child]); 1833 } 1834 debug("read_allocated_block %ld\n", blknr); 1835 1836 return blknr; 1837 } 1838 1839 /** 1840 * ext4fs_reinit_global() - Reinitialize values of ext4 write implementation's 1841 * global pointers 1842 * 1843 * This function assures that for a file with the same name but different size 1844 * the sequential store on the ext4 filesystem will be correct. 1845 * 1846 * In this function the global data, responsible for internal representation 1847 * of the ext4 data are initialized to the reset state. Without this, during 1848 * replacement of the smaller file with the bigger truncation of new file was 1849 * performed. 1850 */ 1851 void ext4fs_reinit_global(void) 1852 { 1853 if (ext4fs_indir1_block != NULL) { 1854 free(ext4fs_indir1_block); 1855 ext4fs_indir1_block = NULL; 1856 ext4fs_indir1_size = 0; 1857 ext4fs_indir1_blkno = -1; 1858 } 1859 if (ext4fs_indir2_block != NULL) { 1860 free(ext4fs_indir2_block); 1861 ext4fs_indir2_block = NULL; 1862 ext4fs_indir2_size = 0; 1863 ext4fs_indir2_blkno = -1; 1864 } 1865 if (ext4fs_indir3_block != NULL) { 1866 free(ext4fs_indir3_block); 1867 ext4fs_indir3_block = NULL; 1868 ext4fs_indir3_size = 0; 1869 ext4fs_indir3_blkno = -1; 1870 } 1871 } 1872 void ext4fs_close(void) 1873 { 1874 if ((ext4fs_file != NULL) && (ext4fs_root != NULL)) { 1875 ext4fs_free_node(ext4fs_file, &ext4fs_root->diropen); 1876 ext4fs_file = NULL; 1877 } 1878 if (ext4fs_root != NULL) { 1879 free(ext4fs_root); 1880 ext4fs_root = NULL; 1881 } 1882 1883 ext4fs_reinit_global(); 1884 } 1885 1886 int ext4fs_iterate_dir(struct ext2fs_node *dir, char *name, 1887 struct ext2fs_node **fnode, int *ftype) 1888 { 1889 unsigned int fpos = 0; 1890 int status; 1891 loff_t actread; 1892 struct ext2fs_node *diro = (struct ext2fs_node *) dir; 1893 1894 #ifdef DEBUG 1895 if (name != NULL) 1896 printf("Iterate dir %s\n", name); 1897 #endif /* of DEBUG */ 1898 if (!diro->inode_read) { 1899 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode); 1900 if (status == 0) 1901 return 0; 1902 } 1903 /* Search the file. */ 1904 while (fpos < le32_to_cpu(diro->inode.size)) { 1905 struct ext2_dirent dirent; 1906 1907 status = ext4fs_read_file(diro, fpos, 1908 sizeof(struct ext2_dirent), 1909 (char *)&dirent, &actread); 1910 if (status < 0) 1911 return 0; 1912 1913 if (dirent.direntlen == 0) { 1914 printf("Failed to iterate over directory %s\n", name); 1915 return 0; 1916 } 1917 1918 if (dirent.namelen != 0) { 1919 char filename[dirent.namelen + 1]; 1920 struct ext2fs_node *fdiro; 1921 int type = FILETYPE_UNKNOWN; 1922 1923 status = ext4fs_read_file(diro, 1924 fpos + 1925 sizeof(struct ext2_dirent), 1926 dirent.namelen, filename, 1927 &actread); 1928 if (status < 0) 1929 return 0; 1930 1931 fdiro = zalloc(sizeof(struct ext2fs_node)); 1932 if (!fdiro) 1933 return 0; 1934 1935 fdiro->data = diro->data; 1936 fdiro->ino = le32_to_cpu(dirent.inode); 1937 1938 filename[dirent.namelen] = '\0'; 1939 1940 if (dirent.filetype != FILETYPE_UNKNOWN) { 1941 fdiro->inode_read = 0; 1942 1943 if (dirent.filetype == FILETYPE_DIRECTORY) 1944 type = FILETYPE_DIRECTORY; 1945 else if (dirent.filetype == FILETYPE_SYMLINK) 1946 type = FILETYPE_SYMLINK; 1947 else if (dirent.filetype == FILETYPE_REG) 1948 type = FILETYPE_REG; 1949 } else { 1950 status = ext4fs_read_inode(diro->data, 1951 le32_to_cpu 1952 (dirent.inode), 1953 &fdiro->inode); 1954 if (status == 0) { 1955 free(fdiro); 1956 return 0; 1957 } 1958 fdiro->inode_read = 1; 1959 1960 if ((le16_to_cpu(fdiro->inode.mode) & 1961 FILETYPE_INO_MASK) == 1962 FILETYPE_INO_DIRECTORY) { 1963 type = FILETYPE_DIRECTORY; 1964 } else if ((le16_to_cpu(fdiro->inode.mode) 1965 & FILETYPE_INO_MASK) == 1966 FILETYPE_INO_SYMLINK) { 1967 type = FILETYPE_SYMLINK; 1968 } else if ((le16_to_cpu(fdiro->inode.mode) 1969 & FILETYPE_INO_MASK) == 1970 FILETYPE_INO_REG) { 1971 type = FILETYPE_REG; 1972 } 1973 } 1974 #ifdef DEBUG 1975 printf("iterate >%s<\n", filename); 1976 #endif /* of DEBUG */ 1977 if ((name != NULL) && (fnode != NULL) 1978 && (ftype != NULL)) { 1979 if (strcmp(filename, name) == 0) { 1980 *ftype = type; 1981 *fnode = fdiro; 1982 return 1; 1983 } 1984 } else { 1985 if (fdiro->inode_read == 0) { 1986 status = ext4fs_read_inode(diro->data, 1987 le32_to_cpu( 1988 dirent.inode), 1989 &fdiro->inode); 1990 if (status == 0) { 1991 free(fdiro); 1992 return 0; 1993 } 1994 fdiro->inode_read = 1; 1995 } 1996 switch (type) { 1997 case FILETYPE_DIRECTORY: 1998 printf("<DIR> "); 1999 break; 2000 case FILETYPE_SYMLINK: 2001 printf("<SYM> "); 2002 break; 2003 case FILETYPE_REG: 2004 printf(" "); 2005 break; 2006 default: 2007 printf("< ? > "); 2008 break; 2009 } 2010 printf("%10u %s\n", 2011 le32_to_cpu(fdiro->inode.size), 2012 filename); 2013 } 2014 free(fdiro); 2015 } 2016 fpos += le16_to_cpu(dirent.direntlen); 2017 } 2018 return 0; 2019 } 2020 2021 static char *ext4fs_read_symlink(struct ext2fs_node *node) 2022 { 2023 char *symlink; 2024 struct ext2fs_node *diro = node; 2025 int status; 2026 loff_t actread; 2027 2028 if (!diro->inode_read) { 2029 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode); 2030 if (status == 0) 2031 return NULL; 2032 } 2033 symlink = zalloc(le32_to_cpu(diro->inode.size) + 1); 2034 if (!symlink) 2035 return NULL; 2036 2037 if (le32_to_cpu(diro->inode.size) < sizeof(diro->inode.b.symlink)) { 2038 strncpy(symlink, diro->inode.b.symlink, 2039 le32_to_cpu(diro->inode.size)); 2040 } else { 2041 status = ext4fs_read_file(diro, 0, 2042 le32_to_cpu(diro->inode.size), 2043 symlink, &actread); 2044 if ((status < 0) || (actread == 0)) { 2045 free(symlink); 2046 return NULL; 2047 } 2048 } 2049 symlink[le32_to_cpu(diro->inode.size)] = '\0'; 2050 return symlink; 2051 } 2052 2053 static int ext4fs_find_file1(const char *currpath, 2054 struct ext2fs_node *currroot, 2055 struct ext2fs_node **currfound, int *foundtype) 2056 { 2057 char fpath[strlen(currpath) + 1]; 2058 char *name = fpath; 2059 char *next; 2060 int status; 2061 int type = FILETYPE_DIRECTORY; 2062 struct ext2fs_node *currnode = currroot; 2063 struct ext2fs_node *oldnode = currroot; 2064 2065 strncpy(fpath, currpath, strlen(currpath) + 1); 2066 2067 /* Remove all leading slashes. */ 2068 while (*name == '/') 2069 name++; 2070 2071 if (!*name) { 2072 *currfound = currnode; 2073 return 1; 2074 } 2075 2076 for (;;) { 2077 int found; 2078 2079 /* Extract the actual part from the pathname. */ 2080 next = strchr(name, '/'); 2081 if (next) { 2082 /* Remove all leading slashes. */ 2083 while (*next == '/') 2084 *(next++) = '\0'; 2085 } 2086 2087 if (type != FILETYPE_DIRECTORY) { 2088 ext4fs_free_node(currnode, currroot); 2089 return 0; 2090 } 2091 2092 oldnode = currnode; 2093 2094 /* Iterate over the directory. */ 2095 found = ext4fs_iterate_dir(currnode, name, &currnode, &type); 2096 if (found == 0) 2097 return 0; 2098 2099 if (found == -1) 2100 break; 2101 2102 /* Read in the symlink and follow it. */ 2103 if (type == FILETYPE_SYMLINK) { 2104 char *symlink; 2105 2106 /* Test if the symlink does not loop. */ 2107 if (++symlinknest == 8) { 2108 ext4fs_free_node(currnode, currroot); 2109 ext4fs_free_node(oldnode, currroot); 2110 return 0; 2111 } 2112 2113 symlink = ext4fs_read_symlink(currnode); 2114 ext4fs_free_node(currnode, currroot); 2115 2116 if (!symlink) { 2117 ext4fs_free_node(oldnode, currroot); 2118 return 0; 2119 } 2120 2121 debug("Got symlink >%s<\n", symlink); 2122 2123 if (symlink[0] == '/') { 2124 ext4fs_free_node(oldnode, currroot); 2125 oldnode = &ext4fs_root->diropen; 2126 } 2127 2128 /* Lookup the node the symlink points to. */ 2129 status = ext4fs_find_file1(symlink, oldnode, 2130 &currnode, &type); 2131 2132 free(symlink); 2133 2134 if (status == 0) { 2135 ext4fs_free_node(oldnode, currroot); 2136 return 0; 2137 } 2138 } 2139 2140 ext4fs_free_node(oldnode, currroot); 2141 2142 /* Found the node! */ 2143 if (!next || *next == '\0') { 2144 *currfound = currnode; 2145 *foundtype = type; 2146 return 1; 2147 } 2148 name = next; 2149 } 2150 return -1; 2151 } 2152 2153 int ext4fs_find_file(const char *path, struct ext2fs_node *rootnode, 2154 struct ext2fs_node **foundnode, int expecttype) 2155 { 2156 int status; 2157 int foundtype = FILETYPE_DIRECTORY; 2158 2159 symlinknest = 0; 2160 if (!path) 2161 return 0; 2162 2163 status = ext4fs_find_file1(path, rootnode, foundnode, &foundtype); 2164 if (status == 0) 2165 return 0; 2166 2167 /* Check if the node that was found was of the expected type. */ 2168 if ((expecttype == FILETYPE_REG) && (foundtype != expecttype)) 2169 return 0; 2170 else if ((expecttype == FILETYPE_DIRECTORY) 2171 && (foundtype != expecttype)) 2172 return 0; 2173 2174 return 1; 2175 } 2176 2177 int ext4fs_open(const char *filename, loff_t *len) 2178 { 2179 struct ext2fs_node *fdiro = NULL; 2180 int status; 2181 2182 if (ext4fs_root == NULL) 2183 return -1; 2184 2185 ext4fs_file = NULL; 2186 status = ext4fs_find_file(filename, &ext4fs_root->diropen, &fdiro, 2187 FILETYPE_REG); 2188 if (status == 0) 2189 goto fail; 2190 2191 if (!fdiro->inode_read) { 2192 status = ext4fs_read_inode(fdiro->data, fdiro->ino, 2193 &fdiro->inode); 2194 if (status == 0) 2195 goto fail; 2196 } 2197 *len = le32_to_cpu(fdiro->inode.size); 2198 ext4fs_file = fdiro; 2199 2200 return 0; 2201 fail: 2202 ext4fs_free_node(fdiro, &ext4fs_root->diropen); 2203 2204 return -1; 2205 } 2206 2207 int ext4fs_mount(unsigned part_length) 2208 { 2209 struct ext2_data *data; 2210 int status; 2211 struct ext_filesystem *fs = get_fs(); 2212 data = zalloc(SUPERBLOCK_SIZE); 2213 if (!data) 2214 return 0; 2215 2216 /* Read the superblock. */ 2217 status = ext4_read_superblock((char *)&data->sblock); 2218 2219 if (status == 0) 2220 goto fail; 2221 2222 /* Make sure this is an ext2 filesystem. */ 2223 if (le16_to_cpu(data->sblock.magic) != EXT2_MAGIC) 2224 goto fail; 2225 2226 /* 2227 * The 64bit feature was enabled when metadata_csum was enabled 2228 * and we do not support metadata_csum (and cannot reliably find 2229 * files when it is set. Refuse to mount. 2230 */ 2231 if (le32_to_cpu(data->sblock.feature_incompat) & EXT4_FEATURE_INCOMPAT_64BIT) { 2232 printf("Unsupported feature found (64bit, possibly metadata_csum), not mounting\n"); 2233 goto fail; 2234 } 2235 2236 if (le32_to_cpu(data->sblock.revision_level) == 0) 2237 fs->inodesz = 128; 2238 else 2239 fs->inodesz = le16_to_cpu(data->sblock.inode_size); 2240 2241 debug("EXT2 rev %d, inode_size %d\n", 2242 le32_to_cpu(data->sblock.revision_level), fs->inodesz); 2243 2244 data->diropen.data = data; 2245 data->diropen.ino = 2; 2246 data->diropen.inode_read = 1; 2247 data->inode = &data->diropen.inode; 2248 2249 status = ext4fs_read_inode(data, 2, data->inode); 2250 if (status == 0) 2251 goto fail; 2252 2253 ext4fs_root = data; 2254 2255 return 1; 2256 fail: 2257 printf("Failed to mount ext2 filesystem...\n"); 2258 free(data); 2259 ext4fs_root = NULL; 2260 2261 return 0; 2262 } 2263