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 unsigned char input; 167 int operand, status; 168 int count = 0; 169 int j = 0; 170 unsigned char *ptr = buffer; 171 struct ext_filesystem *fs = get_fs(); 172 173 if (fs->blksz != 1024) 174 count = 0; 175 else 176 count = 1; 177 178 while (*ptr == 255) { 179 ptr++; 180 count += 8; 181 if (count == (fs->blksz * 8)) 182 return -1; 183 } 184 185 for (j = 0; j < fs->blksz; j++) { 186 input = *ptr; 187 int i = 0; 188 while (i <= 7) { 189 operand = 1 << i; 190 status = input & operand; 191 if (status) { 192 i++; 193 count++; 194 } else { 195 *ptr |= operand; 196 return count; 197 } 198 } 199 ptr = ptr + 1; 200 } 201 202 return -1; 203 } 204 205 int ext4fs_set_block_bmap(long int blockno, unsigned char *buffer, int index) 206 { 207 int i, remainder, status; 208 unsigned char *ptr = buffer; 209 unsigned char operand; 210 i = blockno / 8; 211 remainder = blockno % 8; 212 int blocksize = EXT2_BLOCK_SIZE(ext4fs_root); 213 214 i = i - (index * blocksize); 215 if (blocksize != 1024) { 216 ptr = ptr + i; 217 operand = 1 << remainder; 218 status = *ptr & operand; 219 if (status) 220 return -1; 221 222 *ptr = *ptr | operand; 223 return 0; 224 } else { 225 if (remainder == 0) { 226 ptr = ptr + i - 1; 227 operand = (1 << 7); 228 } else { 229 ptr = ptr + i; 230 operand = (1 << (remainder - 1)); 231 } 232 status = *ptr & operand; 233 if (status) 234 return -1; 235 236 *ptr = *ptr | operand; 237 return 0; 238 } 239 } 240 241 void ext4fs_reset_block_bmap(long int blockno, unsigned char *buffer, int index) 242 { 243 int i, remainder, status; 244 unsigned char *ptr = buffer; 245 unsigned char operand; 246 i = blockno / 8; 247 remainder = blockno % 8; 248 int blocksize = EXT2_BLOCK_SIZE(ext4fs_root); 249 250 i = i - (index * blocksize); 251 if (blocksize != 1024) { 252 ptr = ptr + i; 253 operand = (1 << remainder); 254 status = *ptr & operand; 255 if (status) 256 *ptr = *ptr & ~(operand); 257 } else { 258 if (remainder == 0) { 259 ptr = ptr + i - 1; 260 operand = (1 << 7); 261 } else { 262 ptr = ptr + i; 263 operand = (1 << (remainder - 1)); 264 } 265 status = *ptr & operand; 266 if (status) 267 *ptr = *ptr & ~(operand); 268 } 269 } 270 271 int ext4fs_set_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 * le32_to_cpu(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 return -1; 290 291 *ptr = *ptr | operand; 292 293 return 0; 294 } 295 296 void ext4fs_reset_inode_bmap(int inode_no, unsigned char *buffer, int index) 297 { 298 int i, remainder, status; 299 unsigned char *ptr = buffer; 300 unsigned char operand; 301 302 inode_no -= (index * le32_to_cpu(ext4fs_root->sblock.inodes_per_group)); 303 i = inode_no / 8; 304 remainder = inode_no % 8; 305 if (remainder == 0) { 306 ptr = ptr + i - 1; 307 operand = (1 << 7); 308 } else { 309 ptr = ptr + i; 310 operand = (1 << (remainder - 1)); 311 } 312 status = *ptr & operand; 313 if (status) 314 *ptr = *ptr & ~(operand); 315 } 316 317 uint16_t ext4fs_checksum_update(uint32_t i) 318 { 319 struct ext2_block_group *desc; 320 struct ext_filesystem *fs = get_fs(); 321 uint16_t crc = 0; 322 __le32 le32_i = cpu_to_le32(i); 323 324 desc = (struct ext2_block_group *)&fs->bgd[i]; 325 if (le32_to_cpu(fs->sb->feature_ro_compat) & EXT4_FEATURE_RO_COMPAT_GDT_CSUM) { 326 int offset = offsetof(struct ext2_block_group, bg_checksum); 327 328 crc = ext2fs_crc16(~0, fs->sb->unique_id, 329 sizeof(fs->sb->unique_id)); 330 crc = ext2fs_crc16(crc, &le32_i, sizeof(le32_i)); 331 crc = ext2fs_crc16(crc, desc, offset); 332 offset += sizeof(desc->bg_checksum); /* skip checksum */ 333 assert(offset == sizeof(*desc)); 334 } 335 336 return crc; 337 } 338 339 static int check_void_in_dentry(struct ext2_dirent *dir, char *filename) 340 { 341 int dentry_length; 342 int sizeof_void_space; 343 int new_entry_byte_reqd; 344 short padding_factor = 0; 345 346 if (dir->namelen % 4 != 0) 347 padding_factor = 4 - (dir->namelen % 4); 348 349 dentry_length = sizeof(struct ext2_dirent) + 350 dir->namelen + padding_factor; 351 sizeof_void_space = le16_to_cpu(dir->direntlen) - dentry_length; 352 if (sizeof_void_space == 0) 353 return 0; 354 355 padding_factor = 0; 356 if (strlen(filename) % 4 != 0) 357 padding_factor = 4 - (strlen(filename) % 4); 358 359 new_entry_byte_reqd = strlen(filename) + 360 sizeof(struct ext2_dirent) + padding_factor; 361 if (sizeof_void_space >= new_entry_byte_reqd) { 362 dir->direntlen = cpu_to_le16(dentry_length); 363 return sizeof_void_space; 364 } 365 366 return 0; 367 } 368 369 int ext4fs_update_parent_dentry(char *filename, int file_type) 370 { 371 unsigned int *zero_buffer = NULL; 372 char *root_first_block_buffer = NULL; 373 int blk_idx; 374 long int first_block_no_of_root = 0; 375 int totalbytes = 0; 376 unsigned int new_entry_byte_reqd; 377 int sizeof_void_space = 0; 378 int templength = 0; 379 int inodeno = -1; 380 int status; 381 struct ext_filesystem *fs = get_fs(); 382 /* directory entry */ 383 struct ext2_dirent *dir; 384 char *temp_dir = NULL; 385 uint32_t new_blk_no; 386 uint32_t new_size; 387 uint32_t new_blockcnt; 388 uint32_t directory_blocks; 389 390 zero_buffer = zalloc(fs->blksz); 391 if (!zero_buffer) { 392 printf("No Memory\n"); 393 return -1; 394 } 395 root_first_block_buffer = zalloc(fs->blksz); 396 if (!root_first_block_buffer) { 397 free(zero_buffer); 398 printf("No Memory\n"); 399 return -1; 400 } 401 new_entry_byte_reqd = ROUND(strlen(filename) + 402 sizeof(struct ext2_dirent), 4); 403 restart: 404 directory_blocks = le32_to_cpu(g_parent_inode->size) >> 405 LOG2_BLOCK_SIZE(ext4fs_root); 406 blk_idx = directory_blocks - 1; 407 408 restart_read: 409 /* read the block no allocated to a file */ 410 first_block_no_of_root = read_allocated_block(g_parent_inode, blk_idx); 411 if (first_block_no_of_root <= 0) 412 goto fail; 413 414 status = ext4fs_devread((lbaint_t)first_block_no_of_root 415 * fs->sect_perblk, 416 0, fs->blksz, root_first_block_buffer); 417 if (status == 0) 418 goto fail; 419 420 if (ext4fs_log_journal(root_first_block_buffer, first_block_no_of_root)) 421 goto fail; 422 dir = (struct ext2_dirent *)root_first_block_buffer; 423 totalbytes = 0; 424 425 while (le16_to_cpu(dir->direntlen) > 0) { 426 unsigned short used_len = ROUND(dir->namelen + 427 sizeof(struct ext2_dirent), 4); 428 429 /* last entry of block */ 430 if (fs->blksz - totalbytes == le16_to_cpu(dir->direntlen)) { 431 432 /* check if new entry fits */ 433 if ((used_len + new_entry_byte_reqd) <= 434 le16_to_cpu(dir->direntlen)) { 435 dir->direntlen = cpu_to_le16(used_len); 436 break; 437 } else { 438 if (blk_idx > 0) { 439 printf("Block full, trying previous\n"); 440 blk_idx--; 441 goto restart_read; 442 } 443 printf("All blocks full: Allocate new\n"); 444 445 if (le32_to_cpu(g_parent_inode->flags) & 446 EXT4_EXTENTS_FL) { 447 printf("Directory uses extents\n"); 448 goto fail; 449 } 450 if (directory_blocks >= INDIRECT_BLOCKS) { 451 printf("Directory exceeds limit\n"); 452 goto fail; 453 } 454 new_blk_no = ext4fs_get_new_blk_no(); 455 if (new_blk_no == -1) { 456 printf("no block left to assign\n"); 457 goto fail; 458 } 459 put_ext4((uint64_t)new_blk_no * fs->blksz, zero_buffer, fs->blksz); 460 g_parent_inode->b.blocks. 461 dir_blocks[directory_blocks] = 462 cpu_to_le32(new_blk_no); 463 464 new_size = le32_to_cpu(g_parent_inode->size); 465 new_size += fs->blksz; 466 g_parent_inode->size = cpu_to_le32(new_size); 467 468 new_blockcnt = le32_to_cpu(g_parent_inode->blockcnt); 469 new_blockcnt += fs->sect_perblk; 470 g_parent_inode->blockcnt = cpu_to_le32(new_blockcnt); 471 472 if (ext4fs_put_metadata 473 (root_first_block_buffer, 474 first_block_no_of_root)) 475 goto fail; 476 goto restart; 477 } 478 } 479 480 templength = le16_to_cpu(dir->direntlen); 481 totalbytes = totalbytes + templength; 482 sizeof_void_space = check_void_in_dentry(dir, filename); 483 if (sizeof_void_space) 484 break; 485 486 dir = (struct ext2_dirent *)((char *)dir + templength); 487 } 488 489 /* make a pointer ready for creating next directory entry */ 490 templength = le16_to_cpu(dir->direntlen); 491 totalbytes = totalbytes + templength; 492 dir = (struct ext2_dirent *)((char *)dir + templength); 493 494 /* get the next available inode number */ 495 inodeno = ext4fs_get_new_inode_no(); 496 if (inodeno == -1) { 497 printf("no inode left to assign\n"); 498 goto fail; 499 } 500 dir->inode = cpu_to_le32(inodeno); 501 if (sizeof_void_space) 502 dir->direntlen = cpu_to_le16(sizeof_void_space); 503 else 504 dir->direntlen = cpu_to_le16(fs->blksz - totalbytes); 505 506 dir->namelen = strlen(filename); 507 dir->filetype = FILETYPE_REG; /* regular file */ 508 temp_dir = (char *)dir; 509 temp_dir = temp_dir + sizeof(struct ext2_dirent); 510 memcpy(temp_dir, filename, strlen(filename)); 511 512 /* update or write the 1st block of root inode */ 513 if (ext4fs_put_metadata(root_first_block_buffer, 514 first_block_no_of_root)) 515 goto fail; 516 517 fail: 518 free(zero_buffer); 519 free(root_first_block_buffer); 520 521 return inodeno; 522 } 523 524 static int search_dir(struct ext2_inode *parent_inode, char *dirname) 525 { 526 int status; 527 int inodeno = 0; 528 int offset; 529 int blk_idx; 530 long int blknr; 531 char *block_buffer = NULL; 532 struct ext2_dirent *dir = NULL; 533 struct ext_filesystem *fs = get_fs(); 534 uint32_t directory_blocks; 535 char *direntname; 536 537 directory_blocks = le32_to_cpu(parent_inode->size) >> 538 LOG2_BLOCK_SIZE(ext4fs_root); 539 540 block_buffer = zalloc(fs->blksz); 541 if (!block_buffer) 542 goto fail; 543 544 /* get the block no allocated to a file */ 545 for (blk_idx = 0; blk_idx < directory_blocks; blk_idx++) { 546 blknr = read_allocated_block(parent_inode, blk_idx); 547 if (blknr == 0) 548 goto fail; 549 550 /* read the directory block */ 551 status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 552 0, fs->blksz, (char *)block_buffer); 553 if (status == 0) 554 goto fail; 555 556 offset = 0; 557 do { 558 dir = (struct ext2_dirent *)(block_buffer + offset); 559 direntname = (char*)(dir) + sizeof(struct ext2_dirent); 560 561 int direntlen = le16_to_cpu(dir->direntlen); 562 if (direntlen < sizeof(struct ext2_dirent)) 563 break; 564 565 if (dir->inode && (strlen(dirname) == dir->namelen) && 566 (strncmp(dirname, direntname, dir->namelen) == 0)) { 567 inodeno = le32_to_cpu(dir->inode); 568 break; 569 } 570 571 offset += direntlen; 572 573 } while (offset < fs->blksz); 574 575 if (inodeno > 0) { 576 free(block_buffer); 577 return inodeno; 578 } 579 } 580 581 fail: 582 free(block_buffer); 583 584 return -1; 585 } 586 587 static int find_dir_depth(char *dirname) 588 { 589 char *token = strtok(dirname, "/"); 590 int count = 0; 591 while (token != NULL) { 592 token = strtok(NULL, "/"); 593 count++; 594 } 595 return count + 1 + 1; 596 /* 597 * for example for string /home/temp 598 * depth=home(1)+temp(1)+1 extra for NULL; 599 * so count is 4; 600 */ 601 } 602 603 static int parse_path(char **arr, char *dirname) 604 { 605 char *token = strtok(dirname, "/"); 606 int i = 0; 607 608 /* add root */ 609 arr[i] = zalloc(strlen("/") + 1); 610 if (!arr[i]) 611 return -ENOMEM; 612 memcpy(arr[i++], "/", strlen("/")); 613 614 /* add each path entry after root */ 615 while (token != NULL) { 616 arr[i] = zalloc(strlen(token) + 1); 617 if (!arr[i]) 618 return -ENOMEM; 619 memcpy(arr[i++], token, strlen(token)); 620 token = strtok(NULL, "/"); 621 } 622 arr[i] = NULL; 623 624 return 0; 625 } 626 627 int ext4fs_iget(int inode_no, struct ext2_inode *inode) 628 { 629 if (ext4fs_read_inode(ext4fs_root, inode_no, inode) == 0) 630 return -1; 631 632 return 0; 633 } 634 635 /* 636 * Function: ext4fs_get_parent_inode_num 637 * Return Value: inode Number of the parent directory of file/Directory to be 638 * created 639 * dirname : Input parmater, input path name of the file/directory to be created 640 * dname : Output parameter, to be filled with the name of the directory 641 * extracted from dirname 642 */ 643 int ext4fs_get_parent_inode_num(const char *dirname, char *dname, int flags) 644 { 645 int i; 646 int depth = 0; 647 int matched_inode_no; 648 int result_inode_no = -1; 649 char **ptr = NULL; 650 char *depth_dirname = NULL; 651 char *parse_dirname = NULL; 652 struct ext2_inode *parent_inode = NULL; 653 struct ext2_inode *first_inode = NULL; 654 struct ext2_inode temp_inode; 655 656 if (*dirname != '/') { 657 printf("Please supply Absolute path\n"); 658 return -1; 659 } 660 661 /* TODO: input validation make equivalent to linux */ 662 depth_dirname = zalloc(strlen(dirname) + 1); 663 if (!depth_dirname) 664 return -ENOMEM; 665 666 memcpy(depth_dirname, dirname, strlen(dirname)); 667 depth = find_dir_depth(depth_dirname); 668 parse_dirname = zalloc(strlen(dirname) + 1); 669 if (!parse_dirname) 670 goto fail; 671 memcpy(parse_dirname, dirname, strlen(dirname)); 672 673 /* allocate memory for each directory level */ 674 ptr = zalloc((depth) * sizeof(char *)); 675 if (!ptr) 676 goto fail; 677 if (parse_path(ptr, parse_dirname)) 678 goto fail; 679 parent_inode = zalloc(sizeof(struct ext2_inode)); 680 if (!parent_inode) 681 goto fail; 682 first_inode = zalloc(sizeof(struct ext2_inode)); 683 if (!first_inode) 684 goto fail; 685 memcpy(parent_inode, ext4fs_root->inode, sizeof(struct ext2_inode)); 686 memcpy(first_inode, parent_inode, sizeof(struct ext2_inode)); 687 if (flags & F_FILE) 688 result_inode_no = EXT2_ROOT_INO; 689 for (i = 1; i < depth; i++) { 690 matched_inode_no = search_dir(parent_inode, ptr[i]); 691 if (matched_inode_no == -1) { 692 if (ptr[i + 1] == NULL && i == 1) { 693 result_inode_no = EXT2_ROOT_INO; 694 goto end; 695 } else { 696 if (ptr[i + 1] == NULL) 697 break; 698 printf("Invalid path\n"); 699 result_inode_no = -1; 700 goto fail; 701 } 702 } else { 703 if (ptr[i + 1] != NULL) { 704 memset(parent_inode, '\0', 705 sizeof(struct ext2_inode)); 706 if (ext4fs_iget(matched_inode_no, 707 parent_inode)) { 708 result_inode_no = -1; 709 goto fail; 710 } 711 result_inode_no = matched_inode_no; 712 } else { 713 break; 714 } 715 } 716 } 717 718 end: 719 if (i == 1) 720 matched_inode_no = search_dir(first_inode, ptr[i]); 721 else 722 matched_inode_no = search_dir(parent_inode, ptr[i]); 723 724 if (matched_inode_no != -1) { 725 ext4fs_iget(matched_inode_no, &temp_inode); 726 if (le16_to_cpu(temp_inode.mode) & S_IFDIR) { 727 printf("It is a Directory\n"); 728 result_inode_no = -1; 729 goto fail; 730 } 731 } 732 733 if (strlen(ptr[i]) > 256) { 734 result_inode_no = -1; 735 goto fail; 736 } 737 memcpy(dname, ptr[i], strlen(ptr[i])); 738 739 fail: 740 free(depth_dirname); 741 free(parse_dirname); 742 for (i = 0; i < depth; i++) { 743 if (!ptr[i]) 744 break; 745 free(ptr[i]); 746 } 747 free(ptr); 748 free(parent_inode); 749 free(first_inode); 750 751 return result_inode_no; 752 } 753 754 static int unlink_filename(char *filename, unsigned int blknr) 755 { 756 int totalbytes = 0; 757 int templength = 0; 758 int status, inodeno; 759 int found = 0; 760 char *root_first_block_buffer = NULL; 761 struct ext2_dirent *dir = NULL; 762 struct ext2_dirent *previous_dir = NULL; 763 char *ptr = NULL; 764 struct ext_filesystem *fs = get_fs(); 765 int ret = -1; 766 767 /* get the first block of root */ 768 root_first_block_buffer = zalloc(fs->blksz); 769 if (!root_first_block_buffer) 770 return -ENOMEM; 771 status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 0, 772 fs->blksz, root_first_block_buffer); 773 if (status == 0) 774 goto fail; 775 776 if (ext4fs_log_journal(root_first_block_buffer, blknr)) 777 goto fail; 778 dir = (struct ext2_dirent *)root_first_block_buffer; 779 ptr = (char *)dir; 780 totalbytes = 0; 781 while (le16_to_cpu(dir->direntlen) >= 0) { 782 /* 783 * blocksize-totalbytes because last 784 * directory length i.e., *dir->direntlen 785 * is free availble space in the block that 786 * means it is a last entry of directory entry 787 */ 788 if (dir->inode && (strlen(filename) == dir->namelen) && 789 (strncmp(ptr + sizeof(struct ext2_dirent), 790 filename, dir->namelen) == 0)) { 791 printf("file found, deleting\n"); 792 inodeno = le32_to_cpu(dir->inode); 793 if (previous_dir) { 794 uint16_t new_len; 795 new_len = le16_to_cpu(previous_dir->direntlen); 796 new_len += le16_to_cpu(dir->direntlen); 797 previous_dir->direntlen = cpu_to_le16(new_len); 798 } else { 799 dir->inode = 0; 800 } 801 found = 1; 802 break; 803 } 804 805 if (fs->blksz - totalbytes == le16_to_cpu(dir->direntlen)) 806 break; 807 808 /* traversing the each directory entry */ 809 templength = le16_to_cpu(dir->direntlen); 810 totalbytes = totalbytes + templength; 811 previous_dir = dir; 812 dir = (struct ext2_dirent *)((char *)dir + templength); 813 ptr = (char *)dir; 814 } 815 816 817 if (found == 1) { 818 if (ext4fs_put_metadata(root_first_block_buffer, blknr)) 819 goto fail; 820 ret = inodeno; 821 } 822 fail: 823 free(root_first_block_buffer); 824 825 return ret; 826 } 827 828 int ext4fs_filename_unlink(char *filename) 829 { 830 int blk_idx; 831 long int blknr = -1; 832 int inodeno = -1; 833 uint32_t directory_blocks; 834 835 directory_blocks = le32_to_cpu(g_parent_inode->size) >> 836 LOG2_BLOCK_SIZE(ext4fs_root); 837 838 /* read the block no allocated to a file */ 839 for (blk_idx = 0; blk_idx < directory_blocks; blk_idx++) { 840 blknr = read_allocated_block(g_parent_inode, blk_idx); 841 if (blknr == 0) 842 break; 843 inodeno = unlink_filename(filename, blknr); 844 if (inodeno != -1) 845 return inodeno; 846 } 847 848 return -1; 849 } 850 851 uint32_t ext4fs_get_new_blk_no(void) 852 { 853 short i; 854 short status; 855 int remainder; 856 unsigned int bg_idx; 857 static int prev_bg_bitmap_index = -1; 858 unsigned int blk_per_grp = le32_to_cpu(ext4fs_root->sblock.blocks_per_group); 859 struct ext_filesystem *fs = get_fs(); 860 char *journal_buffer = zalloc(fs->blksz); 861 char *zero_buffer = zalloc(fs->blksz); 862 if (!journal_buffer || !zero_buffer) 863 goto fail; 864 struct ext2_block_group *bgd = (struct ext2_block_group *)fs->gdtable; 865 866 if (fs->first_pass_bbmap == 0) { 867 for (i = 0; i < fs->no_blkgrp; i++) { 868 if (le16_to_cpu(bgd[i].free_blocks)) { 869 if (le16_to_cpu(bgd[i].bg_flags) & EXT4_BG_BLOCK_UNINIT) { 870 uint16_t new_flags; 871 put_ext4((uint64_t)le32_to_cpu(bgd[i].block_id) * fs->blksz, 872 zero_buffer, fs->blksz); 873 new_flags = le16_to_cpu(bgd[i].bg_flags) & ~EXT4_BG_BLOCK_UNINIT; 874 bgd[i].bg_flags = cpu_to_le16(new_flags); 875 memcpy(fs->blk_bmaps[i], zero_buffer, 876 fs->blksz); 877 } 878 fs->curr_blkno = 879 _get_new_blk_no(fs->blk_bmaps[i]); 880 if (fs->curr_blkno == -1) 881 /* if block bitmap is completely fill */ 882 continue; 883 fs->curr_blkno = fs->curr_blkno + 884 (i * fs->blksz * 8); 885 fs->first_pass_bbmap++; 886 ext4fs_bg_free_blocks_dec(&bgd[i]); 887 ext4fs_sb_free_blocks_dec(fs->sb); 888 status = ext4fs_devread( 889 (lbaint_t)le32_to_cpu(bgd[i].block_id) * 890 fs->sect_perblk, 0, 891 fs->blksz, 892 journal_buffer); 893 if (status == 0) 894 goto fail; 895 if (ext4fs_log_journal(journal_buffer, 896 le32_to_cpu(bgd[i].block_id))) 897 goto fail; 898 goto success; 899 } else { 900 debug("no space left on block group %d\n", i); 901 } 902 } 903 904 goto fail; 905 } else { 906 restart: 907 fs->curr_blkno++; 908 /* get the blockbitmap index respective to blockno */ 909 bg_idx = fs->curr_blkno / blk_per_grp; 910 if (fs->blksz == 1024) { 911 remainder = fs->curr_blkno % blk_per_grp; 912 if (!remainder) 913 bg_idx--; 914 } 915 916 /* 917 * To skip completely filled block group bitmaps 918 * Optimize the block allocation 919 */ 920 if (bg_idx >= fs->no_blkgrp) 921 goto fail; 922 923 if (bgd[bg_idx].free_blocks == 0) { 924 debug("block group %u is full. Skipping\n", bg_idx); 925 fs->curr_blkno = fs->curr_blkno + blk_per_grp; 926 fs->curr_blkno--; 927 goto restart; 928 } 929 930 if (le16_to_cpu(bgd[bg_idx].bg_flags) & EXT4_BG_BLOCK_UNINIT) { 931 uint16_t new_flags; 932 memset(zero_buffer, '\0', fs->blksz); 933 put_ext4((uint64_t)le32_to_cpu(bgd[bg_idx].block_id) * fs->blksz, 934 zero_buffer, fs->blksz); 935 memcpy(fs->blk_bmaps[bg_idx], zero_buffer, fs->blksz); 936 new_flags = le16_to_cpu(bgd[bg_idx].bg_flags) & ~EXT4_BG_BLOCK_UNINIT; 937 bgd[bg_idx].bg_flags = cpu_to_le16(new_flags); 938 } 939 940 if (ext4fs_set_block_bmap(fs->curr_blkno, fs->blk_bmaps[bg_idx], 941 bg_idx) != 0) { 942 debug("going for restart for the block no %ld %u\n", 943 fs->curr_blkno, bg_idx); 944 goto restart; 945 } 946 947 /* journal backup */ 948 if (prev_bg_bitmap_index != bg_idx) { 949 memset(journal_buffer, '\0', fs->blksz); 950 status = ext4fs_devread( 951 (lbaint_t)le32_to_cpu(bgd[bg_idx].block_id) 952 * fs->sect_perblk, 953 0, fs->blksz, journal_buffer); 954 if (status == 0) 955 goto fail; 956 if (ext4fs_log_journal(journal_buffer, 957 le32_to_cpu(bgd[bg_idx].block_id))) 958 goto fail; 959 960 prev_bg_bitmap_index = bg_idx; 961 } 962 ext4fs_bg_free_blocks_dec(&bgd[bg_idx]); 963 ext4fs_sb_free_blocks_dec(fs->sb); 964 goto success; 965 } 966 success: 967 free(journal_buffer); 968 free(zero_buffer); 969 970 return fs->curr_blkno; 971 fail: 972 free(journal_buffer); 973 free(zero_buffer); 974 975 return -1; 976 } 977 978 int ext4fs_get_new_inode_no(void) 979 { 980 short i; 981 short status; 982 unsigned int ibmap_idx; 983 static int prev_inode_bitmap_index = -1; 984 unsigned int inodes_per_grp = le32_to_cpu(ext4fs_root->sblock.inodes_per_group); 985 struct ext_filesystem *fs = get_fs(); 986 char *journal_buffer = zalloc(fs->blksz); 987 char *zero_buffer = zalloc(fs->blksz); 988 if (!journal_buffer || !zero_buffer) 989 goto fail; 990 struct ext2_block_group *bgd = (struct ext2_block_group *)fs->gdtable; 991 int has_gdt_chksum = le32_to_cpu(fs->sb->feature_ro_compat) & 992 EXT4_FEATURE_RO_COMPAT_GDT_CSUM ? 1 : 0; 993 994 if (fs->first_pass_ibmap == 0) { 995 for (i = 0; i < fs->no_blkgrp; i++) { 996 if (bgd[i].free_inodes) { 997 if (has_gdt_chksum) 998 bgd[i].bg_itable_unused = 999 bgd[i].free_inodes; 1000 if (le16_to_cpu(bgd[i].bg_flags) & EXT4_BG_INODE_UNINIT) { 1001 int new_flags; 1002 put_ext4((uint64_t)le32_to_cpu(bgd[i].inode_id) * fs->blksz, 1003 zero_buffer, fs->blksz); 1004 new_flags = le16_to_cpu(bgd[i].bg_flags) & ~EXT4_BG_INODE_UNINIT; 1005 bgd[i].bg_flags = cpu_to_le16(new_flags); 1006 memcpy(fs->inode_bmaps[i], 1007 zero_buffer, fs->blksz); 1008 } 1009 fs->curr_inode_no = 1010 _get_new_inode_no(fs->inode_bmaps[i]); 1011 if (fs->curr_inode_no == -1) 1012 /* if block bitmap is completely fill */ 1013 continue; 1014 fs->curr_inode_no = fs->curr_inode_no + 1015 (i * inodes_per_grp); 1016 fs->first_pass_ibmap++; 1017 ext4fs_bg_free_inodes_dec(&bgd[i]); 1018 if (has_gdt_chksum) 1019 ext4fs_bg_itable_unused_dec(&bgd[i]); 1020 ext4fs_sb_free_inodes_dec(fs->sb); 1021 status = ext4fs_devread( 1022 (lbaint_t)le32_to_cpu(bgd[i].inode_id) * 1023 fs->sect_perblk, 0, 1024 fs->blksz, 1025 journal_buffer); 1026 if (status == 0) 1027 goto fail; 1028 if (ext4fs_log_journal(journal_buffer, 1029 le32_to_cpu(bgd[i].inode_id))) 1030 goto fail; 1031 goto success; 1032 } else 1033 debug("no inode left on block group %d\n", i); 1034 } 1035 goto fail; 1036 } else { 1037 restart: 1038 fs->curr_inode_no++; 1039 /* get the blockbitmap index respective to blockno */ 1040 ibmap_idx = fs->curr_inode_no / inodes_per_grp; 1041 if (le16_to_cpu(bgd[ibmap_idx].bg_flags) & EXT4_BG_INODE_UNINIT) { 1042 int new_flags; 1043 memset(zero_buffer, '\0', fs->blksz); 1044 put_ext4((uint64_t)le32_to_cpu(bgd[ibmap_idx].inode_id) * fs->blksz, 1045 zero_buffer, fs->blksz); 1046 new_flags = le16_to_cpu(bgd[ibmap_idx].bg_flags) & ~EXT4_BG_INODE_UNINIT; 1047 bgd[ibmap_idx].bg_flags = cpu_to_le16(new_flags); 1048 memcpy(fs->inode_bmaps[ibmap_idx], zero_buffer, 1049 fs->blksz); 1050 } 1051 1052 if (ext4fs_set_inode_bmap(fs->curr_inode_no, 1053 fs->inode_bmaps[ibmap_idx], 1054 ibmap_idx) != 0) { 1055 debug("going for restart for the block no %d %u\n", 1056 fs->curr_inode_no, ibmap_idx); 1057 goto restart; 1058 } 1059 1060 /* journal backup */ 1061 if (prev_inode_bitmap_index != ibmap_idx) { 1062 memset(journal_buffer, '\0', fs->blksz); 1063 status = ext4fs_devread( 1064 (lbaint_t)le32_to_cpu(bgd[ibmap_idx].inode_id) 1065 * fs->sect_perblk, 1066 0, fs->blksz, journal_buffer); 1067 if (status == 0) 1068 goto fail; 1069 if (ext4fs_log_journal(journal_buffer, 1070 le32_to_cpu(bgd[ibmap_idx].inode_id))) 1071 goto fail; 1072 prev_inode_bitmap_index = ibmap_idx; 1073 } 1074 ext4fs_bg_free_inodes_dec(&bgd[ibmap_idx]); 1075 if (has_gdt_chksum) 1076 bgd[ibmap_idx].bg_itable_unused = 1077 bgd[ibmap_idx].free_inodes; 1078 ext4fs_sb_free_inodes_dec(fs->sb); 1079 goto success; 1080 } 1081 1082 success: 1083 free(journal_buffer); 1084 free(zero_buffer); 1085 1086 return fs->curr_inode_no; 1087 fail: 1088 free(journal_buffer); 1089 free(zero_buffer); 1090 1091 return -1; 1092 1093 } 1094 1095 1096 static void alloc_single_indirect_block(struct ext2_inode *file_inode, 1097 unsigned int *total_remaining_blocks, 1098 unsigned int *no_blks_reqd) 1099 { 1100 short i; 1101 short status; 1102 long int actual_block_no; 1103 long int si_blockno; 1104 /* si :single indirect */ 1105 __le32 *si_buffer = NULL; 1106 __le32 *si_start_addr = NULL; 1107 struct ext_filesystem *fs = get_fs(); 1108 1109 if (*total_remaining_blocks != 0) { 1110 si_buffer = zalloc(fs->blksz); 1111 if (!si_buffer) { 1112 printf("No Memory\n"); 1113 return; 1114 } 1115 si_start_addr = si_buffer; 1116 si_blockno = ext4fs_get_new_blk_no(); 1117 if (si_blockno == -1) { 1118 printf("no block left to assign\n"); 1119 goto fail; 1120 } 1121 (*no_blks_reqd)++; 1122 debug("SIPB %ld: %u\n", si_blockno, *total_remaining_blocks); 1123 1124 status = ext4fs_devread((lbaint_t)si_blockno * fs->sect_perblk, 1125 0, fs->blksz, (char *)si_buffer); 1126 memset(si_buffer, '\0', fs->blksz); 1127 if (status == 0) 1128 goto fail; 1129 1130 for (i = 0; i < (fs->blksz / sizeof(int)); i++) { 1131 actual_block_no = ext4fs_get_new_blk_no(); 1132 if (actual_block_no == -1) { 1133 printf("no block left to assign\n"); 1134 goto fail; 1135 } 1136 *si_buffer = cpu_to_le32(actual_block_no); 1137 debug("SIAB %u: %u\n", *si_buffer, 1138 *total_remaining_blocks); 1139 1140 si_buffer++; 1141 (*total_remaining_blocks)--; 1142 if (*total_remaining_blocks == 0) 1143 break; 1144 } 1145 1146 /* write the block to disk */ 1147 put_ext4(((uint64_t) ((uint64_t)si_blockno * (uint64_t)fs->blksz)), 1148 si_start_addr, fs->blksz); 1149 file_inode->b.blocks.indir_block = cpu_to_le32(si_blockno); 1150 } 1151 fail: 1152 free(si_start_addr); 1153 } 1154 1155 static void alloc_double_indirect_block(struct ext2_inode *file_inode, 1156 unsigned int *total_remaining_blocks, 1157 unsigned int *no_blks_reqd) 1158 { 1159 short i; 1160 short j; 1161 short status; 1162 long int actual_block_no; 1163 /* di:double indirect */ 1164 long int di_blockno_parent; 1165 long int di_blockno_child; 1166 __le32 *di_parent_buffer = NULL; 1167 __le32 *di_child_buff = NULL; 1168 __le32 *di_block_start_addr = NULL; 1169 __le32 *di_child_buff_start = NULL; 1170 struct ext_filesystem *fs = get_fs(); 1171 1172 if (*total_remaining_blocks != 0) { 1173 /* double indirect parent block connecting to inode */ 1174 di_blockno_parent = ext4fs_get_new_blk_no(); 1175 if (di_blockno_parent == -1) { 1176 printf("no block left to assign\n"); 1177 goto fail; 1178 } 1179 di_parent_buffer = zalloc(fs->blksz); 1180 if (!di_parent_buffer) 1181 goto fail; 1182 1183 di_block_start_addr = di_parent_buffer; 1184 (*no_blks_reqd)++; 1185 debug("DIPB %ld: %u\n", di_blockno_parent, 1186 *total_remaining_blocks); 1187 1188 status = ext4fs_devread((lbaint_t)di_blockno_parent * 1189 fs->sect_perblk, 0, 1190 fs->blksz, (char *)di_parent_buffer); 1191 1192 if (!status) { 1193 printf("%s: Device read error!\n", __func__); 1194 goto fail; 1195 } 1196 memset(di_parent_buffer, '\0', fs->blksz); 1197 1198 /* 1199 * start:for each double indirect parent 1200 * block create one more block 1201 */ 1202 for (i = 0; i < (fs->blksz / sizeof(int)); i++) { 1203 di_blockno_child = ext4fs_get_new_blk_no(); 1204 if (di_blockno_child == -1) { 1205 printf("no block left to assign\n"); 1206 goto fail; 1207 } 1208 di_child_buff = zalloc(fs->blksz); 1209 if (!di_child_buff) 1210 goto fail; 1211 1212 di_child_buff_start = di_child_buff; 1213 *di_parent_buffer = cpu_to_le32(di_blockno_child); 1214 di_parent_buffer++; 1215 (*no_blks_reqd)++; 1216 debug("DICB %ld: %u\n", di_blockno_child, 1217 *total_remaining_blocks); 1218 1219 status = ext4fs_devread((lbaint_t)di_blockno_child * 1220 fs->sect_perblk, 0, 1221 fs->blksz, 1222 (char *)di_child_buff); 1223 1224 if (!status) { 1225 printf("%s: Device read error!\n", __func__); 1226 goto fail; 1227 } 1228 memset(di_child_buff, '\0', fs->blksz); 1229 /* filling of actual datablocks for each child */ 1230 for (j = 0; j < (fs->blksz / sizeof(int)); j++) { 1231 actual_block_no = ext4fs_get_new_blk_no(); 1232 if (actual_block_no == -1) { 1233 printf("no block left to assign\n"); 1234 goto fail; 1235 } 1236 *di_child_buff = cpu_to_le32(actual_block_no); 1237 debug("DIAB %ld: %u\n", actual_block_no, 1238 *total_remaining_blocks); 1239 1240 di_child_buff++; 1241 (*total_remaining_blocks)--; 1242 if (*total_remaining_blocks == 0) 1243 break; 1244 } 1245 /* write the block table */ 1246 put_ext4(((uint64_t) ((uint64_t)di_blockno_child * (uint64_t)fs->blksz)), 1247 di_child_buff_start, fs->blksz); 1248 free(di_child_buff_start); 1249 di_child_buff_start = NULL; 1250 1251 if (*total_remaining_blocks == 0) 1252 break; 1253 } 1254 put_ext4(((uint64_t) ((uint64_t)di_blockno_parent * (uint64_t)fs->blksz)), 1255 di_block_start_addr, fs->blksz); 1256 file_inode->b.blocks.double_indir_block = cpu_to_le32(di_blockno_parent); 1257 } 1258 fail: 1259 free(di_block_start_addr); 1260 } 1261 1262 static void alloc_triple_indirect_block(struct ext2_inode *file_inode, 1263 unsigned int *total_remaining_blocks, 1264 unsigned int *no_blks_reqd) 1265 { 1266 short i; 1267 short j; 1268 short k; 1269 long int actual_block_no; 1270 /* ti: Triple Indirect */ 1271 long int ti_gp_blockno; 1272 long int ti_parent_blockno; 1273 long int ti_child_blockno; 1274 __le32 *ti_gp_buff = NULL; 1275 __le32 *ti_parent_buff = NULL; 1276 __le32 *ti_child_buff = NULL; 1277 __le32 *ti_gp_buff_start_addr = NULL; 1278 __le32 *ti_pbuff_start_addr = NULL; 1279 __le32 *ti_cbuff_start_addr = NULL; 1280 struct ext_filesystem *fs = get_fs(); 1281 if (*total_remaining_blocks != 0) { 1282 /* triple indirect grand parent block connecting to inode */ 1283 ti_gp_blockno = ext4fs_get_new_blk_no(); 1284 if (ti_gp_blockno == -1) { 1285 printf("no block left to assign\n"); 1286 return; 1287 } 1288 ti_gp_buff = zalloc(fs->blksz); 1289 if (!ti_gp_buff) 1290 return; 1291 1292 ti_gp_buff_start_addr = ti_gp_buff; 1293 (*no_blks_reqd)++; 1294 debug("TIGPB %ld: %u\n", ti_gp_blockno, 1295 *total_remaining_blocks); 1296 1297 /* for each 4 byte grand parent entry create one more block */ 1298 for (i = 0; i < (fs->blksz / sizeof(int)); i++) { 1299 ti_parent_blockno = ext4fs_get_new_blk_no(); 1300 if (ti_parent_blockno == -1) { 1301 printf("no block left to assign\n"); 1302 goto fail; 1303 } 1304 ti_parent_buff = zalloc(fs->blksz); 1305 if (!ti_parent_buff) 1306 goto fail; 1307 1308 ti_pbuff_start_addr = ti_parent_buff; 1309 *ti_gp_buff = cpu_to_le32(ti_parent_blockno); 1310 ti_gp_buff++; 1311 (*no_blks_reqd)++; 1312 debug("TIPB %ld: %u\n", ti_parent_blockno, 1313 *total_remaining_blocks); 1314 1315 /* for each 4 byte entry parent create one more block */ 1316 for (j = 0; j < (fs->blksz / sizeof(int)); j++) { 1317 ti_child_blockno = ext4fs_get_new_blk_no(); 1318 if (ti_child_blockno == -1) { 1319 printf("no block left assign\n"); 1320 goto fail1; 1321 } 1322 ti_child_buff = zalloc(fs->blksz); 1323 if (!ti_child_buff) 1324 goto fail1; 1325 1326 ti_cbuff_start_addr = ti_child_buff; 1327 *ti_parent_buff = cpu_to_le32(ti_child_blockno); 1328 ti_parent_buff++; 1329 (*no_blks_reqd)++; 1330 debug("TICB %ld: %u\n", ti_parent_blockno, 1331 *total_remaining_blocks); 1332 1333 /* fill actual datablocks for each child */ 1334 for (k = 0; k < (fs->blksz / sizeof(int)); 1335 k++) { 1336 actual_block_no = 1337 ext4fs_get_new_blk_no(); 1338 if (actual_block_no == -1) { 1339 printf("no block left\n"); 1340 free(ti_cbuff_start_addr); 1341 goto fail1; 1342 } 1343 *ti_child_buff = cpu_to_le32(actual_block_no); 1344 debug("TIAB %ld: %u\n", actual_block_no, 1345 *total_remaining_blocks); 1346 1347 ti_child_buff++; 1348 (*total_remaining_blocks)--; 1349 if (*total_remaining_blocks == 0) 1350 break; 1351 } 1352 /* write the child block */ 1353 put_ext4(((uint64_t) ((uint64_t)ti_child_blockno * 1354 (uint64_t)fs->blksz)), 1355 ti_cbuff_start_addr, fs->blksz); 1356 free(ti_cbuff_start_addr); 1357 1358 if (*total_remaining_blocks == 0) 1359 break; 1360 } 1361 /* write the parent block */ 1362 put_ext4(((uint64_t) ((uint64_t)ti_parent_blockno * (uint64_t)fs->blksz)), 1363 ti_pbuff_start_addr, fs->blksz); 1364 free(ti_pbuff_start_addr); 1365 1366 if (*total_remaining_blocks == 0) 1367 break; 1368 } 1369 /* write the grand parent block */ 1370 put_ext4(((uint64_t) ((uint64_t)ti_gp_blockno * (uint64_t)fs->blksz)), 1371 ti_gp_buff_start_addr, fs->blksz); 1372 file_inode->b.blocks.triple_indir_block = cpu_to_le32(ti_gp_blockno); 1373 free(ti_gp_buff_start_addr); 1374 return; 1375 } 1376 fail1: 1377 free(ti_pbuff_start_addr); 1378 fail: 1379 free(ti_gp_buff_start_addr); 1380 } 1381 1382 void ext4fs_allocate_blocks(struct ext2_inode *file_inode, 1383 unsigned int total_remaining_blocks, 1384 unsigned int *total_no_of_block) 1385 { 1386 short i; 1387 long int direct_blockno; 1388 unsigned int no_blks_reqd = 0; 1389 1390 /* allocation of direct blocks */ 1391 for (i = 0; total_remaining_blocks && i < INDIRECT_BLOCKS; i++) { 1392 direct_blockno = ext4fs_get_new_blk_no(); 1393 if (direct_blockno == -1) { 1394 printf("no block left to assign\n"); 1395 return; 1396 } 1397 file_inode->b.blocks.dir_blocks[i] = cpu_to_le32(direct_blockno); 1398 debug("DB %ld: %u\n", direct_blockno, total_remaining_blocks); 1399 1400 total_remaining_blocks--; 1401 } 1402 1403 alloc_single_indirect_block(file_inode, &total_remaining_blocks, 1404 &no_blks_reqd); 1405 alloc_double_indirect_block(file_inode, &total_remaining_blocks, 1406 &no_blks_reqd); 1407 alloc_triple_indirect_block(file_inode, &total_remaining_blocks, 1408 &no_blks_reqd); 1409 *total_no_of_block += no_blks_reqd; 1410 } 1411 1412 #endif 1413 1414 static struct ext4_extent_header *ext4fs_get_extent_block 1415 (struct ext2_data *data, char *buf, 1416 struct ext4_extent_header *ext_block, 1417 uint32_t fileblock, int log2_blksz) 1418 { 1419 struct ext4_extent_idx *index; 1420 unsigned long long block; 1421 int blksz = EXT2_BLOCK_SIZE(data); 1422 int i; 1423 1424 while (1) { 1425 index = (struct ext4_extent_idx *)(ext_block + 1); 1426 1427 if (le16_to_cpu(ext_block->eh_magic) != EXT4_EXT_MAGIC) 1428 return NULL; 1429 1430 if (ext_block->eh_depth == 0) 1431 return ext_block; 1432 i = -1; 1433 do { 1434 i++; 1435 if (i >= le16_to_cpu(ext_block->eh_entries)) 1436 break; 1437 } while (fileblock >= le32_to_cpu(index[i].ei_block)); 1438 1439 if (--i < 0) 1440 return NULL; 1441 1442 block = le16_to_cpu(index[i].ei_leaf_hi); 1443 block = (block << 32) + le32_to_cpu(index[i].ei_leaf_lo); 1444 1445 if (ext4fs_devread((lbaint_t)block << log2_blksz, 0, blksz, 1446 buf)) 1447 ext_block = (struct ext4_extent_header *)buf; 1448 else 1449 return NULL; 1450 } 1451 } 1452 1453 static int ext4fs_blockgroup 1454 (struct ext2_data *data, int group, struct ext2_block_group *blkgrp) 1455 { 1456 long int blkno; 1457 unsigned int blkoff, desc_per_blk; 1458 int log2blksz = get_fs()->dev_desc->log2blksz; 1459 1460 desc_per_blk = EXT2_BLOCK_SIZE(data) / sizeof(struct ext2_block_group); 1461 1462 blkno = le32_to_cpu(data->sblock.first_data_block) + 1 + 1463 group / desc_per_blk; 1464 blkoff = (group % desc_per_blk) * sizeof(struct ext2_block_group); 1465 1466 debug("ext4fs read %d group descriptor (blkno %ld blkoff %u)\n", 1467 group, blkno, blkoff); 1468 1469 return ext4fs_devread((lbaint_t)blkno << 1470 (LOG2_BLOCK_SIZE(data) - log2blksz), 1471 blkoff, sizeof(struct ext2_block_group), 1472 (char *)blkgrp); 1473 } 1474 1475 int ext4fs_read_inode(struct ext2_data *data, int ino, struct ext2_inode *inode) 1476 { 1477 struct ext2_block_group blkgrp; 1478 struct ext2_sblock *sblock = &data->sblock; 1479 struct ext_filesystem *fs = get_fs(); 1480 int log2blksz = get_fs()->dev_desc->log2blksz; 1481 int inodes_per_block, status; 1482 long int blkno; 1483 unsigned int blkoff; 1484 1485 /* It is easier to calculate if the first inode is 0. */ 1486 ino--; 1487 status = ext4fs_blockgroup(data, ino / le32_to_cpu 1488 (sblock->inodes_per_group), &blkgrp); 1489 if (status == 0) 1490 return 0; 1491 1492 inodes_per_block = EXT2_BLOCK_SIZE(data) / fs->inodesz; 1493 blkno = le32_to_cpu(blkgrp.inode_table_id) + 1494 (ino % le32_to_cpu(sblock->inodes_per_group)) / inodes_per_block; 1495 blkoff = (ino % inodes_per_block) * fs->inodesz; 1496 /* Read the inode. */ 1497 status = ext4fs_devread((lbaint_t)blkno << (LOG2_BLOCK_SIZE(data) - 1498 log2blksz), blkoff, 1499 sizeof(struct ext2_inode), (char *)inode); 1500 if (status == 0) 1501 return 0; 1502 1503 return 1; 1504 } 1505 1506 long int read_allocated_block(struct ext2_inode *inode, int fileblock) 1507 { 1508 long int blknr; 1509 int blksz; 1510 int log2_blksz; 1511 int status; 1512 long int rblock; 1513 long int perblock_parent; 1514 long int perblock_child; 1515 unsigned long long start; 1516 /* get the blocksize of the filesystem */ 1517 blksz = EXT2_BLOCK_SIZE(ext4fs_root); 1518 log2_blksz = LOG2_BLOCK_SIZE(ext4fs_root) 1519 - get_fs()->dev_desc->log2blksz; 1520 1521 if (le32_to_cpu(inode->flags) & EXT4_EXTENTS_FL) { 1522 char *buf = zalloc(blksz); 1523 if (!buf) 1524 return -ENOMEM; 1525 struct ext4_extent_header *ext_block; 1526 struct ext4_extent *extent; 1527 int i = -1; 1528 ext_block = 1529 ext4fs_get_extent_block(ext4fs_root, buf, 1530 (struct ext4_extent_header *) 1531 inode->b.blocks.dir_blocks, 1532 fileblock, log2_blksz); 1533 if (!ext_block) { 1534 printf("invalid extent block\n"); 1535 free(buf); 1536 return -EINVAL; 1537 } 1538 1539 extent = (struct ext4_extent *)(ext_block + 1); 1540 1541 do { 1542 i++; 1543 if (i >= le16_to_cpu(ext_block->eh_entries)) 1544 break; 1545 } while (fileblock >= le32_to_cpu(extent[i].ee_block)); 1546 if (--i >= 0) { 1547 fileblock -= le32_to_cpu(extent[i].ee_block); 1548 if (fileblock >= le16_to_cpu(extent[i].ee_len)) { 1549 free(buf); 1550 return 0; 1551 } 1552 1553 start = le16_to_cpu(extent[i].ee_start_hi); 1554 start = (start << 32) + 1555 le32_to_cpu(extent[i].ee_start_lo); 1556 free(buf); 1557 return fileblock + start; 1558 } 1559 1560 printf("Extent Error\n"); 1561 free(buf); 1562 return -1; 1563 } 1564 1565 /* Direct blocks. */ 1566 if (fileblock < INDIRECT_BLOCKS) 1567 blknr = le32_to_cpu(inode->b.blocks.dir_blocks[fileblock]); 1568 1569 /* Indirect. */ 1570 else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4))) { 1571 if (ext4fs_indir1_block == NULL) { 1572 ext4fs_indir1_block = zalloc(blksz); 1573 if (ext4fs_indir1_block == NULL) { 1574 printf("** SI ext2fs read block (indir 1)" 1575 "malloc failed. **\n"); 1576 return -1; 1577 } 1578 ext4fs_indir1_size = blksz; 1579 ext4fs_indir1_blkno = -1; 1580 } 1581 if (blksz != ext4fs_indir1_size) { 1582 free(ext4fs_indir1_block); 1583 ext4fs_indir1_block = NULL; 1584 ext4fs_indir1_size = 0; 1585 ext4fs_indir1_blkno = -1; 1586 ext4fs_indir1_block = zalloc(blksz); 1587 if (ext4fs_indir1_block == NULL) { 1588 printf("** SI ext2fs read block (indir 1):" 1589 "malloc failed. **\n"); 1590 return -1; 1591 } 1592 ext4fs_indir1_size = blksz; 1593 } 1594 if ((le32_to_cpu(inode->b.blocks.indir_block) << 1595 log2_blksz) != ext4fs_indir1_blkno) { 1596 status = 1597 ext4fs_devread((lbaint_t)le32_to_cpu 1598 (inode->b.blocks. 1599 indir_block) << log2_blksz, 0, 1600 blksz, (char *)ext4fs_indir1_block); 1601 if (status == 0) { 1602 printf("** SI ext2fs read block (indir 1)" 1603 "failed. **\n"); 1604 return 0; 1605 } 1606 ext4fs_indir1_blkno = 1607 le32_to_cpu(inode->b.blocks. 1608 indir_block) << log2_blksz; 1609 } 1610 blknr = le32_to_cpu(ext4fs_indir1_block 1611 [fileblock - INDIRECT_BLOCKS]); 1612 } 1613 /* Double indirect. */ 1614 else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4 * 1615 (blksz / 4 + 1)))) { 1616 1617 long int perblock = blksz / 4; 1618 long int rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4); 1619 1620 if (ext4fs_indir1_block == NULL) { 1621 ext4fs_indir1_block = zalloc(blksz); 1622 if (ext4fs_indir1_block == NULL) { 1623 printf("** DI ext2fs read block (indir 2 1)" 1624 "malloc failed. **\n"); 1625 return -1; 1626 } 1627 ext4fs_indir1_size = blksz; 1628 ext4fs_indir1_blkno = -1; 1629 } 1630 if (blksz != ext4fs_indir1_size) { 1631 free(ext4fs_indir1_block); 1632 ext4fs_indir1_block = NULL; 1633 ext4fs_indir1_size = 0; 1634 ext4fs_indir1_blkno = -1; 1635 ext4fs_indir1_block = zalloc(blksz); 1636 if (ext4fs_indir1_block == NULL) { 1637 printf("** DI ext2fs read block (indir 2 1)" 1638 "malloc failed. **\n"); 1639 return -1; 1640 } 1641 ext4fs_indir1_size = blksz; 1642 } 1643 if ((le32_to_cpu(inode->b.blocks.double_indir_block) << 1644 log2_blksz) != ext4fs_indir1_blkno) { 1645 status = 1646 ext4fs_devread((lbaint_t)le32_to_cpu 1647 (inode->b.blocks. 1648 double_indir_block) << log2_blksz, 1649 0, blksz, 1650 (char *)ext4fs_indir1_block); 1651 if (status == 0) { 1652 printf("** DI ext2fs read block (indir 2 1)" 1653 "failed. **\n"); 1654 return -1; 1655 } 1656 ext4fs_indir1_blkno = 1657 le32_to_cpu(inode->b.blocks.double_indir_block) << 1658 log2_blksz; 1659 } 1660 1661 if (ext4fs_indir2_block == NULL) { 1662 ext4fs_indir2_block = zalloc(blksz); 1663 if (ext4fs_indir2_block == NULL) { 1664 printf("** DI ext2fs read block (indir 2 2)" 1665 "malloc failed. **\n"); 1666 return -1; 1667 } 1668 ext4fs_indir2_size = blksz; 1669 ext4fs_indir2_blkno = -1; 1670 } 1671 if (blksz != ext4fs_indir2_size) { 1672 free(ext4fs_indir2_block); 1673 ext4fs_indir2_block = NULL; 1674 ext4fs_indir2_size = 0; 1675 ext4fs_indir2_blkno = -1; 1676 ext4fs_indir2_block = zalloc(blksz); 1677 if (ext4fs_indir2_block == NULL) { 1678 printf("** DI ext2fs read block (indir 2 2)" 1679 "malloc failed. **\n"); 1680 return -1; 1681 } 1682 ext4fs_indir2_size = blksz; 1683 } 1684 if ((le32_to_cpu(ext4fs_indir1_block[rblock / perblock]) << 1685 log2_blksz) != ext4fs_indir2_blkno) { 1686 status = ext4fs_devread((lbaint_t)le32_to_cpu 1687 (ext4fs_indir1_block 1688 [rblock / 1689 perblock]) << log2_blksz, 0, 1690 blksz, 1691 (char *)ext4fs_indir2_block); 1692 if (status == 0) { 1693 printf("** DI ext2fs read block (indir 2 2)" 1694 "failed. **\n"); 1695 return -1; 1696 } 1697 ext4fs_indir2_blkno = 1698 le32_to_cpu(ext4fs_indir1_block[rblock 1699 / 1700 perblock]) << 1701 log2_blksz; 1702 } 1703 blknr = le32_to_cpu(ext4fs_indir2_block[rblock % perblock]); 1704 } 1705 /* Tripple indirect. */ 1706 else { 1707 rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4 + 1708 (blksz / 4 * blksz / 4)); 1709 perblock_child = blksz / 4; 1710 perblock_parent = ((blksz / 4) * (blksz / 4)); 1711 1712 if (ext4fs_indir1_block == NULL) { 1713 ext4fs_indir1_block = zalloc(blksz); 1714 if (ext4fs_indir1_block == NULL) { 1715 printf("** TI ext2fs read block (indir 2 1)" 1716 "malloc failed. **\n"); 1717 return -1; 1718 } 1719 ext4fs_indir1_size = blksz; 1720 ext4fs_indir1_blkno = -1; 1721 } 1722 if (blksz != ext4fs_indir1_size) { 1723 free(ext4fs_indir1_block); 1724 ext4fs_indir1_block = NULL; 1725 ext4fs_indir1_size = 0; 1726 ext4fs_indir1_blkno = -1; 1727 ext4fs_indir1_block = zalloc(blksz); 1728 if (ext4fs_indir1_block == NULL) { 1729 printf("** TI ext2fs read block (indir 2 1)" 1730 "malloc failed. **\n"); 1731 return -1; 1732 } 1733 ext4fs_indir1_size = blksz; 1734 } 1735 if ((le32_to_cpu(inode->b.blocks.triple_indir_block) << 1736 log2_blksz) != ext4fs_indir1_blkno) { 1737 status = ext4fs_devread 1738 ((lbaint_t) 1739 le32_to_cpu(inode->b.blocks.triple_indir_block) 1740 << log2_blksz, 0, blksz, 1741 (char *)ext4fs_indir1_block); 1742 if (status == 0) { 1743 printf("** TI ext2fs read block (indir 2 1)" 1744 "failed. **\n"); 1745 return -1; 1746 } 1747 ext4fs_indir1_blkno = 1748 le32_to_cpu(inode->b.blocks.triple_indir_block) << 1749 log2_blksz; 1750 } 1751 1752 if (ext4fs_indir2_block == NULL) { 1753 ext4fs_indir2_block = zalloc(blksz); 1754 if (ext4fs_indir2_block == NULL) { 1755 printf("** TI ext2fs read block (indir 2 2)" 1756 "malloc failed. **\n"); 1757 return -1; 1758 } 1759 ext4fs_indir2_size = blksz; 1760 ext4fs_indir2_blkno = -1; 1761 } 1762 if (blksz != ext4fs_indir2_size) { 1763 free(ext4fs_indir2_block); 1764 ext4fs_indir2_block = NULL; 1765 ext4fs_indir2_size = 0; 1766 ext4fs_indir2_blkno = -1; 1767 ext4fs_indir2_block = zalloc(blksz); 1768 if (ext4fs_indir2_block == NULL) { 1769 printf("** TI ext2fs read block (indir 2 2)" 1770 "malloc failed. **\n"); 1771 return -1; 1772 } 1773 ext4fs_indir2_size = blksz; 1774 } 1775 if ((le32_to_cpu(ext4fs_indir1_block[rblock / 1776 perblock_parent]) << 1777 log2_blksz) 1778 != ext4fs_indir2_blkno) { 1779 status = ext4fs_devread((lbaint_t)le32_to_cpu 1780 (ext4fs_indir1_block 1781 [rblock / 1782 perblock_parent]) << 1783 log2_blksz, 0, blksz, 1784 (char *)ext4fs_indir2_block); 1785 if (status == 0) { 1786 printf("** TI ext2fs read block (indir 2 2)" 1787 "failed. **\n"); 1788 return -1; 1789 } 1790 ext4fs_indir2_blkno = 1791 le32_to_cpu(ext4fs_indir1_block[rblock / 1792 perblock_parent]) 1793 << log2_blksz; 1794 } 1795 1796 if (ext4fs_indir3_block == NULL) { 1797 ext4fs_indir3_block = zalloc(blksz); 1798 if (ext4fs_indir3_block == NULL) { 1799 printf("** TI ext2fs read block (indir 2 2)" 1800 "malloc failed. **\n"); 1801 return -1; 1802 } 1803 ext4fs_indir3_size = blksz; 1804 ext4fs_indir3_blkno = -1; 1805 } 1806 if (blksz != ext4fs_indir3_size) { 1807 free(ext4fs_indir3_block); 1808 ext4fs_indir3_block = NULL; 1809 ext4fs_indir3_size = 0; 1810 ext4fs_indir3_blkno = -1; 1811 ext4fs_indir3_block = zalloc(blksz); 1812 if (ext4fs_indir3_block == NULL) { 1813 printf("** TI ext2fs read block (indir 2 2)" 1814 "malloc failed. **\n"); 1815 return -1; 1816 } 1817 ext4fs_indir3_size = blksz; 1818 } 1819 if ((le32_to_cpu(ext4fs_indir2_block[rblock 1820 / 1821 perblock_child]) << 1822 log2_blksz) != ext4fs_indir3_blkno) { 1823 status = 1824 ext4fs_devread((lbaint_t)le32_to_cpu 1825 (ext4fs_indir2_block 1826 [(rblock / perblock_child) 1827 % (blksz / 4)]) << log2_blksz, 0, 1828 blksz, (char *)ext4fs_indir3_block); 1829 if (status == 0) { 1830 printf("** TI ext2fs read block (indir 2 2)" 1831 "failed. **\n"); 1832 return -1; 1833 } 1834 ext4fs_indir3_blkno = 1835 le32_to_cpu(ext4fs_indir2_block[(rblock / 1836 perblock_child) % 1837 (blksz / 1838 4)]) << 1839 log2_blksz; 1840 } 1841 1842 blknr = le32_to_cpu(ext4fs_indir3_block 1843 [rblock % perblock_child]); 1844 } 1845 debug("read_allocated_block %ld\n", blknr); 1846 1847 return blknr; 1848 } 1849 1850 /** 1851 * ext4fs_reinit_global() - Reinitialize values of ext4 write implementation's 1852 * global pointers 1853 * 1854 * This function assures that for a file with the same name but different size 1855 * the sequential store on the ext4 filesystem will be correct. 1856 * 1857 * In this function the global data, responsible for internal representation 1858 * of the ext4 data are initialized to the reset state. Without this, during 1859 * replacement of the smaller file with the bigger truncation of new file was 1860 * performed. 1861 */ 1862 void ext4fs_reinit_global(void) 1863 { 1864 if (ext4fs_indir1_block != NULL) { 1865 free(ext4fs_indir1_block); 1866 ext4fs_indir1_block = NULL; 1867 ext4fs_indir1_size = 0; 1868 ext4fs_indir1_blkno = -1; 1869 } 1870 if (ext4fs_indir2_block != NULL) { 1871 free(ext4fs_indir2_block); 1872 ext4fs_indir2_block = NULL; 1873 ext4fs_indir2_size = 0; 1874 ext4fs_indir2_blkno = -1; 1875 } 1876 if (ext4fs_indir3_block != NULL) { 1877 free(ext4fs_indir3_block); 1878 ext4fs_indir3_block = NULL; 1879 ext4fs_indir3_size = 0; 1880 ext4fs_indir3_blkno = -1; 1881 } 1882 } 1883 void ext4fs_close(void) 1884 { 1885 if ((ext4fs_file != NULL) && (ext4fs_root != NULL)) { 1886 ext4fs_free_node(ext4fs_file, &ext4fs_root->diropen); 1887 ext4fs_file = NULL; 1888 } 1889 if (ext4fs_root != NULL) { 1890 free(ext4fs_root); 1891 ext4fs_root = NULL; 1892 } 1893 1894 ext4fs_reinit_global(); 1895 } 1896 1897 int ext4fs_iterate_dir(struct ext2fs_node *dir, char *name, 1898 struct ext2fs_node **fnode, int *ftype) 1899 { 1900 unsigned int fpos = 0; 1901 int status; 1902 loff_t actread; 1903 struct ext2fs_node *diro = (struct ext2fs_node *) dir; 1904 1905 #ifdef DEBUG 1906 if (name != NULL) 1907 printf("Iterate dir %s\n", name); 1908 #endif /* of DEBUG */ 1909 if (!diro->inode_read) { 1910 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode); 1911 if (status == 0) 1912 return 0; 1913 } 1914 /* Search the file. */ 1915 while (fpos < le32_to_cpu(diro->inode.size)) { 1916 struct ext2_dirent dirent; 1917 1918 status = ext4fs_read_file(diro, fpos, 1919 sizeof(struct ext2_dirent), 1920 (char *)&dirent, &actread); 1921 if (status < 0) 1922 return 0; 1923 1924 if (dirent.direntlen == 0) { 1925 printf("Failed to iterate over directory %s\n", name); 1926 return 0; 1927 } 1928 1929 if (dirent.namelen != 0) { 1930 char filename[dirent.namelen + 1]; 1931 struct ext2fs_node *fdiro; 1932 int type = FILETYPE_UNKNOWN; 1933 1934 status = ext4fs_read_file(diro, 1935 fpos + 1936 sizeof(struct ext2_dirent), 1937 dirent.namelen, filename, 1938 &actread); 1939 if (status < 0) 1940 return 0; 1941 1942 fdiro = zalloc(sizeof(struct ext2fs_node)); 1943 if (!fdiro) 1944 return 0; 1945 1946 fdiro->data = diro->data; 1947 fdiro->ino = le32_to_cpu(dirent.inode); 1948 1949 filename[dirent.namelen] = '\0'; 1950 1951 if (dirent.filetype != FILETYPE_UNKNOWN) { 1952 fdiro->inode_read = 0; 1953 1954 if (dirent.filetype == FILETYPE_DIRECTORY) 1955 type = FILETYPE_DIRECTORY; 1956 else if (dirent.filetype == FILETYPE_SYMLINK) 1957 type = FILETYPE_SYMLINK; 1958 else if (dirent.filetype == FILETYPE_REG) 1959 type = FILETYPE_REG; 1960 } else { 1961 status = ext4fs_read_inode(diro->data, 1962 le32_to_cpu 1963 (dirent.inode), 1964 &fdiro->inode); 1965 if (status == 0) { 1966 free(fdiro); 1967 return 0; 1968 } 1969 fdiro->inode_read = 1; 1970 1971 if ((le16_to_cpu(fdiro->inode.mode) & 1972 FILETYPE_INO_MASK) == 1973 FILETYPE_INO_DIRECTORY) { 1974 type = FILETYPE_DIRECTORY; 1975 } else if ((le16_to_cpu(fdiro->inode.mode) 1976 & FILETYPE_INO_MASK) == 1977 FILETYPE_INO_SYMLINK) { 1978 type = FILETYPE_SYMLINK; 1979 } else if ((le16_to_cpu(fdiro->inode.mode) 1980 & FILETYPE_INO_MASK) == 1981 FILETYPE_INO_REG) { 1982 type = FILETYPE_REG; 1983 } 1984 } 1985 #ifdef DEBUG 1986 printf("iterate >%s<\n", filename); 1987 #endif /* of DEBUG */ 1988 if ((name != NULL) && (fnode != NULL) 1989 && (ftype != NULL)) { 1990 if (strcmp(filename, name) == 0) { 1991 *ftype = type; 1992 *fnode = fdiro; 1993 return 1; 1994 } 1995 } else { 1996 if (fdiro->inode_read == 0) { 1997 status = ext4fs_read_inode(diro->data, 1998 le32_to_cpu( 1999 dirent.inode), 2000 &fdiro->inode); 2001 if (status == 0) { 2002 free(fdiro); 2003 return 0; 2004 } 2005 fdiro->inode_read = 1; 2006 } 2007 switch (type) { 2008 case FILETYPE_DIRECTORY: 2009 printf("<DIR> "); 2010 break; 2011 case FILETYPE_SYMLINK: 2012 printf("<SYM> "); 2013 break; 2014 case FILETYPE_REG: 2015 printf(" "); 2016 break; 2017 default: 2018 printf("< ? > "); 2019 break; 2020 } 2021 printf("%10u %s\n", 2022 le32_to_cpu(fdiro->inode.size), 2023 filename); 2024 } 2025 free(fdiro); 2026 } 2027 fpos += le16_to_cpu(dirent.direntlen); 2028 } 2029 return 0; 2030 } 2031 2032 static char *ext4fs_read_symlink(struct ext2fs_node *node) 2033 { 2034 char *symlink; 2035 struct ext2fs_node *diro = node; 2036 int status; 2037 loff_t actread; 2038 2039 if (!diro->inode_read) { 2040 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode); 2041 if (status == 0) 2042 return NULL; 2043 } 2044 symlink = zalloc(le32_to_cpu(diro->inode.size) + 1); 2045 if (!symlink) 2046 return NULL; 2047 2048 if (le32_to_cpu(diro->inode.size) < sizeof(diro->inode.b.symlink)) { 2049 strncpy(symlink, diro->inode.b.symlink, 2050 le32_to_cpu(diro->inode.size)); 2051 } else { 2052 status = ext4fs_read_file(diro, 0, 2053 le32_to_cpu(diro->inode.size), 2054 symlink, &actread); 2055 if ((status < 0) || (actread == 0)) { 2056 free(symlink); 2057 return NULL; 2058 } 2059 } 2060 symlink[le32_to_cpu(diro->inode.size)] = '\0'; 2061 return symlink; 2062 } 2063 2064 static int ext4fs_find_file1(const char *currpath, 2065 struct ext2fs_node *currroot, 2066 struct ext2fs_node **currfound, int *foundtype) 2067 { 2068 char fpath[strlen(currpath) + 1]; 2069 char *name = fpath; 2070 char *next; 2071 int status; 2072 int type = FILETYPE_DIRECTORY; 2073 struct ext2fs_node *currnode = currroot; 2074 struct ext2fs_node *oldnode = currroot; 2075 2076 strncpy(fpath, currpath, strlen(currpath) + 1); 2077 2078 /* Remove all leading slashes. */ 2079 while (*name == '/') 2080 name++; 2081 2082 if (!*name) { 2083 *currfound = currnode; 2084 return 1; 2085 } 2086 2087 for (;;) { 2088 int found; 2089 2090 /* Extract the actual part from the pathname. */ 2091 next = strchr(name, '/'); 2092 if (next) { 2093 /* Remove all leading slashes. */ 2094 while (*next == '/') 2095 *(next++) = '\0'; 2096 } 2097 2098 if (type != FILETYPE_DIRECTORY) { 2099 ext4fs_free_node(currnode, currroot); 2100 return 0; 2101 } 2102 2103 oldnode = currnode; 2104 2105 /* Iterate over the directory. */ 2106 found = ext4fs_iterate_dir(currnode, name, &currnode, &type); 2107 if (found == 0) 2108 return 0; 2109 2110 if (found == -1) 2111 break; 2112 2113 /* Read in the symlink and follow it. */ 2114 if (type == FILETYPE_SYMLINK) { 2115 char *symlink; 2116 2117 /* Test if the symlink does not loop. */ 2118 if (++symlinknest == 8) { 2119 ext4fs_free_node(currnode, currroot); 2120 ext4fs_free_node(oldnode, currroot); 2121 return 0; 2122 } 2123 2124 symlink = ext4fs_read_symlink(currnode); 2125 ext4fs_free_node(currnode, currroot); 2126 2127 if (!symlink) { 2128 ext4fs_free_node(oldnode, currroot); 2129 return 0; 2130 } 2131 2132 debug("Got symlink >%s<\n", symlink); 2133 2134 if (symlink[0] == '/') { 2135 ext4fs_free_node(oldnode, currroot); 2136 oldnode = &ext4fs_root->diropen; 2137 } 2138 2139 /* Lookup the node the symlink points to. */ 2140 status = ext4fs_find_file1(symlink, oldnode, 2141 &currnode, &type); 2142 2143 free(symlink); 2144 2145 if (status == 0) { 2146 ext4fs_free_node(oldnode, currroot); 2147 return 0; 2148 } 2149 } 2150 2151 ext4fs_free_node(oldnode, currroot); 2152 2153 /* Found the node! */ 2154 if (!next || *next == '\0') { 2155 *currfound = currnode; 2156 *foundtype = type; 2157 return 1; 2158 } 2159 name = next; 2160 } 2161 return -1; 2162 } 2163 2164 int ext4fs_find_file(const char *path, struct ext2fs_node *rootnode, 2165 struct ext2fs_node **foundnode, int expecttype) 2166 { 2167 int status; 2168 int foundtype = FILETYPE_DIRECTORY; 2169 2170 symlinknest = 0; 2171 if (!path) 2172 return 0; 2173 2174 status = ext4fs_find_file1(path, rootnode, foundnode, &foundtype); 2175 if (status == 0) 2176 return 0; 2177 2178 /* Check if the node that was found was of the expected type. */ 2179 if ((expecttype == FILETYPE_REG) && (foundtype != expecttype)) 2180 return 0; 2181 else if ((expecttype == FILETYPE_DIRECTORY) 2182 && (foundtype != expecttype)) 2183 return 0; 2184 2185 return 1; 2186 } 2187 2188 int ext4fs_open(const char *filename, loff_t *len) 2189 { 2190 struct ext2fs_node *fdiro = NULL; 2191 int status; 2192 2193 if (ext4fs_root == NULL) 2194 return -1; 2195 2196 ext4fs_file = NULL; 2197 status = ext4fs_find_file(filename, &ext4fs_root->diropen, &fdiro, 2198 FILETYPE_REG); 2199 if (status == 0) 2200 goto fail; 2201 2202 if (!fdiro->inode_read) { 2203 status = ext4fs_read_inode(fdiro->data, fdiro->ino, 2204 &fdiro->inode); 2205 if (status == 0) 2206 goto fail; 2207 } 2208 *len = le32_to_cpu(fdiro->inode.size); 2209 ext4fs_file = fdiro; 2210 2211 return 0; 2212 fail: 2213 ext4fs_free_node(fdiro, &ext4fs_root->diropen); 2214 2215 return -1; 2216 } 2217 2218 int ext4fs_mount(unsigned part_length) 2219 { 2220 struct ext2_data *data; 2221 int status; 2222 struct ext_filesystem *fs = get_fs(); 2223 data = zalloc(SUPERBLOCK_SIZE); 2224 if (!data) 2225 return 0; 2226 2227 /* Read the superblock. */ 2228 status = ext4_read_superblock((char *)&data->sblock); 2229 2230 if (status == 0) 2231 goto fail; 2232 2233 /* Make sure this is an ext2 filesystem. */ 2234 if (le16_to_cpu(data->sblock.magic) != EXT2_MAGIC) 2235 goto fail; 2236 2237 /* 2238 * The 64bit feature was enabled when metadata_csum was enabled 2239 * and we do not support metadata_csum (and cannot reliably find 2240 * files when it is set. Refuse to mount. 2241 */ 2242 if (le32_to_cpu(data->sblock.feature_incompat) & EXT4_FEATURE_INCOMPAT_64BIT) { 2243 printf("Unsupported feature found (64bit, possibly metadata_csum), not mounting\n"); 2244 goto fail; 2245 } 2246 2247 if (le32_to_cpu(data->sblock.revision_level) == 0) 2248 fs->inodesz = 128; 2249 else 2250 fs->inodesz = le16_to_cpu(data->sblock.inode_size); 2251 2252 debug("EXT2 rev %d, inode_size %d\n", 2253 le32_to_cpu(data->sblock.revision_level), fs->inodesz); 2254 2255 data->diropen.data = data; 2256 data->diropen.ino = 2; 2257 data->diropen.inode_read = 1; 2258 data->inode = &data->diropen.inode; 2259 2260 status = ext4fs_read_inode(data, 2, data->inode); 2261 if (status == 0) 2262 goto fail; 2263 2264 ext4fs_root = data; 2265 2266 return 1; 2267 fail: 2268 printf("Failed to mount ext2 filesystem...\n"); 2269 free(data); 2270 ext4fs_root = NULL; 2271 2272 return 0; 2273 } 2274