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 fs->curr_blkno++; 907 restart: 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 = (bg_idx + 1) * blk_per_grp; 926 if (fs->blksz == 1024) 927 fs->curr_blkno += 1; 928 goto restart; 929 } 930 931 if (le16_to_cpu(bgd[bg_idx].bg_flags) & EXT4_BG_BLOCK_UNINIT) { 932 uint16_t new_flags; 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 fs->curr_blkno++; 945 goto restart; 946 } 947 948 /* journal backup */ 949 if (prev_bg_bitmap_index != bg_idx) { 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 put_ext4((uint64_t)le32_to_cpu(bgd[ibmap_idx].inode_id) * fs->blksz, 1044 zero_buffer, fs->blksz); 1045 new_flags = le16_to_cpu(bgd[ibmap_idx].bg_flags) & ~EXT4_BG_INODE_UNINIT; 1046 bgd[ibmap_idx].bg_flags = cpu_to_le16(new_flags); 1047 memcpy(fs->inode_bmaps[ibmap_idx], zero_buffer, 1048 fs->blksz); 1049 } 1050 1051 if (ext4fs_set_inode_bmap(fs->curr_inode_no, 1052 fs->inode_bmaps[ibmap_idx], 1053 ibmap_idx) != 0) { 1054 debug("going for restart for the block no %d %u\n", 1055 fs->curr_inode_no, ibmap_idx); 1056 goto restart; 1057 } 1058 1059 /* journal backup */ 1060 if (prev_inode_bitmap_index != ibmap_idx) { 1061 memset(journal_buffer, '\0', fs->blksz); 1062 status = ext4fs_devread( 1063 (lbaint_t)le32_to_cpu(bgd[ibmap_idx].inode_id) 1064 * fs->sect_perblk, 1065 0, fs->blksz, journal_buffer); 1066 if (status == 0) 1067 goto fail; 1068 if (ext4fs_log_journal(journal_buffer, 1069 le32_to_cpu(bgd[ibmap_idx].inode_id))) 1070 goto fail; 1071 prev_inode_bitmap_index = ibmap_idx; 1072 } 1073 ext4fs_bg_free_inodes_dec(&bgd[ibmap_idx]); 1074 if (has_gdt_chksum) 1075 bgd[ibmap_idx].bg_itable_unused = 1076 bgd[ibmap_idx].free_inodes; 1077 ext4fs_sb_free_inodes_dec(fs->sb); 1078 goto success; 1079 } 1080 1081 success: 1082 free(journal_buffer); 1083 free(zero_buffer); 1084 1085 return fs->curr_inode_no; 1086 fail: 1087 free(journal_buffer); 1088 free(zero_buffer); 1089 1090 return -1; 1091 1092 } 1093 1094 1095 static void alloc_single_indirect_block(struct ext2_inode *file_inode, 1096 unsigned int *total_remaining_blocks, 1097 unsigned int *no_blks_reqd) 1098 { 1099 short i; 1100 short status; 1101 long int actual_block_no; 1102 long int si_blockno; 1103 /* si :single indirect */ 1104 __le32 *si_buffer = NULL; 1105 __le32 *si_start_addr = NULL; 1106 struct ext_filesystem *fs = get_fs(); 1107 1108 if (*total_remaining_blocks != 0) { 1109 si_buffer = zalloc(fs->blksz); 1110 if (!si_buffer) { 1111 printf("No Memory\n"); 1112 return; 1113 } 1114 si_start_addr = si_buffer; 1115 si_blockno = ext4fs_get_new_blk_no(); 1116 if (si_blockno == -1) { 1117 printf("no block left to assign\n"); 1118 goto fail; 1119 } 1120 (*no_blks_reqd)++; 1121 debug("SIPB %ld: %u\n", si_blockno, *total_remaining_blocks); 1122 1123 status = ext4fs_devread((lbaint_t)si_blockno * fs->sect_perblk, 1124 0, fs->blksz, (char *)si_buffer); 1125 memset(si_buffer, '\0', fs->blksz); 1126 if (status == 0) 1127 goto fail; 1128 1129 for (i = 0; i < (fs->blksz / sizeof(int)); i++) { 1130 actual_block_no = ext4fs_get_new_blk_no(); 1131 if (actual_block_no == -1) { 1132 printf("no block left to assign\n"); 1133 goto fail; 1134 } 1135 *si_buffer = cpu_to_le32(actual_block_no); 1136 debug("SIAB %u: %u\n", *si_buffer, 1137 *total_remaining_blocks); 1138 1139 si_buffer++; 1140 (*total_remaining_blocks)--; 1141 if (*total_remaining_blocks == 0) 1142 break; 1143 } 1144 1145 /* write the block to disk */ 1146 put_ext4(((uint64_t) ((uint64_t)si_blockno * (uint64_t)fs->blksz)), 1147 si_start_addr, fs->blksz); 1148 file_inode->b.blocks.indir_block = cpu_to_le32(si_blockno); 1149 } 1150 fail: 1151 free(si_start_addr); 1152 } 1153 1154 static void alloc_double_indirect_block(struct ext2_inode *file_inode, 1155 unsigned int *total_remaining_blocks, 1156 unsigned int *no_blks_reqd) 1157 { 1158 short i; 1159 short j; 1160 short status; 1161 long int actual_block_no; 1162 /* di:double indirect */ 1163 long int di_blockno_parent; 1164 long int di_blockno_child; 1165 __le32 *di_parent_buffer = NULL; 1166 __le32 *di_child_buff = NULL; 1167 __le32 *di_block_start_addr = NULL; 1168 __le32 *di_child_buff_start = NULL; 1169 struct ext_filesystem *fs = get_fs(); 1170 1171 if (*total_remaining_blocks != 0) { 1172 /* double indirect parent block connecting to inode */ 1173 di_blockno_parent = ext4fs_get_new_blk_no(); 1174 if (di_blockno_parent == -1) { 1175 printf("no block left to assign\n"); 1176 goto fail; 1177 } 1178 di_parent_buffer = zalloc(fs->blksz); 1179 if (!di_parent_buffer) 1180 goto fail; 1181 1182 di_block_start_addr = di_parent_buffer; 1183 (*no_blks_reqd)++; 1184 debug("DIPB %ld: %u\n", di_blockno_parent, 1185 *total_remaining_blocks); 1186 1187 status = ext4fs_devread((lbaint_t)di_blockno_parent * 1188 fs->sect_perblk, 0, 1189 fs->blksz, (char *)di_parent_buffer); 1190 1191 if (!status) { 1192 printf("%s: Device read error!\n", __func__); 1193 goto fail; 1194 } 1195 memset(di_parent_buffer, '\0', fs->blksz); 1196 1197 /* 1198 * start:for each double indirect parent 1199 * block create one more block 1200 */ 1201 for (i = 0; i < (fs->blksz / sizeof(int)); i++) { 1202 di_blockno_child = ext4fs_get_new_blk_no(); 1203 if (di_blockno_child == -1) { 1204 printf("no block left to assign\n"); 1205 goto fail; 1206 } 1207 di_child_buff = zalloc(fs->blksz); 1208 if (!di_child_buff) 1209 goto fail; 1210 1211 di_child_buff_start = di_child_buff; 1212 *di_parent_buffer = cpu_to_le32(di_blockno_child); 1213 di_parent_buffer++; 1214 (*no_blks_reqd)++; 1215 debug("DICB %ld: %u\n", di_blockno_child, 1216 *total_remaining_blocks); 1217 1218 status = ext4fs_devread((lbaint_t)di_blockno_child * 1219 fs->sect_perblk, 0, 1220 fs->blksz, 1221 (char *)di_child_buff); 1222 1223 if (!status) { 1224 printf("%s: Device read error!\n", __func__); 1225 goto fail; 1226 } 1227 memset(di_child_buff, '\0', fs->blksz); 1228 /* filling of actual datablocks for each child */ 1229 for (j = 0; j < (fs->blksz / sizeof(int)); j++) { 1230 actual_block_no = ext4fs_get_new_blk_no(); 1231 if (actual_block_no == -1) { 1232 printf("no block left to assign\n"); 1233 goto fail; 1234 } 1235 *di_child_buff = cpu_to_le32(actual_block_no); 1236 debug("DIAB %ld: %u\n", actual_block_no, 1237 *total_remaining_blocks); 1238 1239 di_child_buff++; 1240 (*total_remaining_blocks)--; 1241 if (*total_remaining_blocks == 0) 1242 break; 1243 } 1244 /* write the block table */ 1245 put_ext4(((uint64_t) ((uint64_t)di_blockno_child * (uint64_t)fs->blksz)), 1246 di_child_buff_start, fs->blksz); 1247 free(di_child_buff_start); 1248 di_child_buff_start = NULL; 1249 1250 if (*total_remaining_blocks == 0) 1251 break; 1252 } 1253 put_ext4(((uint64_t) ((uint64_t)di_blockno_parent * (uint64_t)fs->blksz)), 1254 di_block_start_addr, fs->blksz); 1255 file_inode->b.blocks.double_indir_block = cpu_to_le32(di_blockno_parent); 1256 } 1257 fail: 1258 free(di_block_start_addr); 1259 } 1260 1261 static void alloc_triple_indirect_block(struct ext2_inode *file_inode, 1262 unsigned int *total_remaining_blocks, 1263 unsigned int *no_blks_reqd) 1264 { 1265 short i; 1266 short j; 1267 short k; 1268 long int actual_block_no; 1269 /* ti: Triple Indirect */ 1270 long int ti_gp_blockno; 1271 long int ti_parent_blockno; 1272 long int ti_child_blockno; 1273 __le32 *ti_gp_buff = NULL; 1274 __le32 *ti_parent_buff = NULL; 1275 __le32 *ti_child_buff = NULL; 1276 __le32 *ti_gp_buff_start_addr = NULL; 1277 __le32 *ti_pbuff_start_addr = NULL; 1278 __le32 *ti_cbuff_start_addr = NULL; 1279 struct ext_filesystem *fs = get_fs(); 1280 if (*total_remaining_blocks != 0) { 1281 /* triple indirect grand parent block connecting to inode */ 1282 ti_gp_blockno = ext4fs_get_new_blk_no(); 1283 if (ti_gp_blockno == -1) { 1284 printf("no block left to assign\n"); 1285 return; 1286 } 1287 ti_gp_buff = zalloc(fs->blksz); 1288 if (!ti_gp_buff) 1289 return; 1290 1291 ti_gp_buff_start_addr = ti_gp_buff; 1292 (*no_blks_reqd)++; 1293 debug("TIGPB %ld: %u\n", ti_gp_blockno, 1294 *total_remaining_blocks); 1295 1296 /* for each 4 byte grand parent entry create one more block */ 1297 for (i = 0; i < (fs->blksz / sizeof(int)); i++) { 1298 ti_parent_blockno = ext4fs_get_new_blk_no(); 1299 if (ti_parent_blockno == -1) { 1300 printf("no block left to assign\n"); 1301 goto fail; 1302 } 1303 ti_parent_buff = zalloc(fs->blksz); 1304 if (!ti_parent_buff) 1305 goto fail; 1306 1307 ti_pbuff_start_addr = ti_parent_buff; 1308 *ti_gp_buff = cpu_to_le32(ti_parent_blockno); 1309 ti_gp_buff++; 1310 (*no_blks_reqd)++; 1311 debug("TIPB %ld: %u\n", ti_parent_blockno, 1312 *total_remaining_blocks); 1313 1314 /* for each 4 byte entry parent create one more block */ 1315 for (j = 0; j < (fs->blksz / sizeof(int)); j++) { 1316 ti_child_blockno = ext4fs_get_new_blk_no(); 1317 if (ti_child_blockno == -1) { 1318 printf("no block left assign\n"); 1319 goto fail1; 1320 } 1321 ti_child_buff = zalloc(fs->blksz); 1322 if (!ti_child_buff) 1323 goto fail1; 1324 1325 ti_cbuff_start_addr = ti_child_buff; 1326 *ti_parent_buff = cpu_to_le32(ti_child_blockno); 1327 ti_parent_buff++; 1328 (*no_blks_reqd)++; 1329 debug("TICB %ld: %u\n", ti_parent_blockno, 1330 *total_remaining_blocks); 1331 1332 /* fill actual datablocks for each child */ 1333 for (k = 0; k < (fs->blksz / sizeof(int)); 1334 k++) { 1335 actual_block_no = 1336 ext4fs_get_new_blk_no(); 1337 if (actual_block_no == -1) { 1338 printf("no block left\n"); 1339 free(ti_cbuff_start_addr); 1340 goto fail1; 1341 } 1342 *ti_child_buff = cpu_to_le32(actual_block_no); 1343 debug("TIAB %ld: %u\n", actual_block_no, 1344 *total_remaining_blocks); 1345 1346 ti_child_buff++; 1347 (*total_remaining_blocks)--; 1348 if (*total_remaining_blocks == 0) 1349 break; 1350 } 1351 /* write the child block */ 1352 put_ext4(((uint64_t) ((uint64_t)ti_child_blockno * 1353 (uint64_t)fs->blksz)), 1354 ti_cbuff_start_addr, fs->blksz); 1355 free(ti_cbuff_start_addr); 1356 1357 if (*total_remaining_blocks == 0) 1358 break; 1359 } 1360 /* write the parent block */ 1361 put_ext4(((uint64_t) ((uint64_t)ti_parent_blockno * (uint64_t)fs->blksz)), 1362 ti_pbuff_start_addr, fs->blksz); 1363 free(ti_pbuff_start_addr); 1364 1365 if (*total_remaining_blocks == 0) 1366 break; 1367 } 1368 /* write the grand parent block */ 1369 put_ext4(((uint64_t) ((uint64_t)ti_gp_blockno * (uint64_t)fs->blksz)), 1370 ti_gp_buff_start_addr, fs->blksz); 1371 file_inode->b.blocks.triple_indir_block = cpu_to_le32(ti_gp_blockno); 1372 free(ti_gp_buff_start_addr); 1373 return; 1374 } 1375 fail1: 1376 free(ti_pbuff_start_addr); 1377 fail: 1378 free(ti_gp_buff_start_addr); 1379 } 1380 1381 void ext4fs_allocate_blocks(struct ext2_inode *file_inode, 1382 unsigned int total_remaining_blocks, 1383 unsigned int *total_no_of_block) 1384 { 1385 short i; 1386 long int direct_blockno; 1387 unsigned int no_blks_reqd = 0; 1388 1389 /* allocation of direct blocks */ 1390 for (i = 0; total_remaining_blocks && i < INDIRECT_BLOCKS; i++) { 1391 direct_blockno = ext4fs_get_new_blk_no(); 1392 if (direct_blockno == -1) { 1393 printf("no block left to assign\n"); 1394 return; 1395 } 1396 file_inode->b.blocks.dir_blocks[i] = cpu_to_le32(direct_blockno); 1397 debug("DB %ld: %u\n", direct_blockno, total_remaining_blocks); 1398 1399 total_remaining_blocks--; 1400 } 1401 1402 alloc_single_indirect_block(file_inode, &total_remaining_blocks, 1403 &no_blks_reqd); 1404 alloc_double_indirect_block(file_inode, &total_remaining_blocks, 1405 &no_blks_reqd); 1406 alloc_triple_indirect_block(file_inode, &total_remaining_blocks, 1407 &no_blks_reqd); 1408 *total_no_of_block += no_blks_reqd; 1409 } 1410 1411 #endif 1412 1413 static struct ext4_extent_header *ext4fs_get_extent_block 1414 (struct ext2_data *data, char *buf, 1415 struct ext4_extent_header *ext_block, 1416 uint32_t fileblock, int log2_blksz) 1417 { 1418 struct ext4_extent_idx *index; 1419 unsigned long long block; 1420 int blksz = EXT2_BLOCK_SIZE(data); 1421 int i; 1422 1423 while (1) { 1424 index = (struct ext4_extent_idx *)(ext_block + 1); 1425 1426 if (le16_to_cpu(ext_block->eh_magic) != EXT4_EXT_MAGIC) 1427 return NULL; 1428 1429 if (ext_block->eh_depth == 0) 1430 return ext_block; 1431 i = -1; 1432 do { 1433 i++; 1434 if (i >= le16_to_cpu(ext_block->eh_entries)) 1435 break; 1436 } while (fileblock >= le32_to_cpu(index[i].ei_block)); 1437 1438 if (--i < 0) 1439 return NULL; 1440 1441 block = le16_to_cpu(index[i].ei_leaf_hi); 1442 block = (block << 32) + le32_to_cpu(index[i].ei_leaf_lo); 1443 1444 if (ext4fs_devread((lbaint_t)block << log2_blksz, 0, blksz, 1445 buf)) 1446 ext_block = (struct ext4_extent_header *)buf; 1447 else 1448 return NULL; 1449 } 1450 } 1451 1452 static int ext4fs_blockgroup 1453 (struct ext2_data *data, int group, struct ext2_block_group *blkgrp) 1454 { 1455 long int blkno; 1456 unsigned int blkoff, desc_per_blk; 1457 int log2blksz = get_fs()->dev_desc->log2blksz; 1458 1459 desc_per_blk = EXT2_BLOCK_SIZE(data) / sizeof(struct ext2_block_group); 1460 1461 blkno = le32_to_cpu(data->sblock.first_data_block) + 1 + 1462 group / desc_per_blk; 1463 blkoff = (group % desc_per_blk) * sizeof(struct ext2_block_group); 1464 1465 debug("ext4fs read %d group descriptor (blkno %ld blkoff %u)\n", 1466 group, blkno, blkoff); 1467 1468 return ext4fs_devread((lbaint_t)blkno << 1469 (LOG2_BLOCK_SIZE(data) - log2blksz), 1470 blkoff, sizeof(struct ext2_block_group), 1471 (char *)blkgrp); 1472 } 1473 1474 int ext4fs_read_inode(struct ext2_data *data, int ino, struct ext2_inode *inode) 1475 { 1476 struct ext2_block_group blkgrp; 1477 struct ext2_sblock *sblock = &data->sblock; 1478 struct ext_filesystem *fs = get_fs(); 1479 int log2blksz = get_fs()->dev_desc->log2blksz; 1480 int inodes_per_block, status; 1481 long int blkno; 1482 unsigned int blkoff; 1483 1484 /* It is easier to calculate if the first inode is 0. */ 1485 ino--; 1486 status = ext4fs_blockgroup(data, ino / le32_to_cpu 1487 (sblock->inodes_per_group), &blkgrp); 1488 if (status == 0) 1489 return 0; 1490 1491 inodes_per_block = EXT2_BLOCK_SIZE(data) / fs->inodesz; 1492 blkno = le32_to_cpu(blkgrp.inode_table_id) + 1493 (ino % le32_to_cpu(sblock->inodes_per_group)) / inodes_per_block; 1494 blkoff = (ino % inodes_per_block) * fs->inodesz; 1495 /* Read the inode. */ 1496 status = ext4fs_devread((lbaint_t)blkno << (LOG2_BLOCK_SIZE(data) - 1497 log2blksz), blkoff, 1498 sizeof(struct ext2_inode), (char *)inode); 1499 if (status == 0) 1500 return 0; 1501 1502 return 1; 1503 } 1504 1505 long int read_allocated_block(struct ext2_inode *inode, int fileblock) 1506 { 1507 long int blknr; 1508 int blksz; 1509 int log2_blksz; 1510 int status; 1511 long int rblock; 1512 long int perblock_parent; 1513 long int perblock_child; 1514 unsigned long long start; 1515 /* get the blocksize of the filesystem */ 1516 blksz = EXT2_BLOCK_SIZE(ext4fs_root); 1517 log2_blksz = LOG2_BLOCK_SIZE(ext4fs_root) 1518 - get_fs()->dev_desc->log2blksz; 1519 1520 if (le32_to_cpu(inode->flags) & EXT4_EXTENTS_FL) { 1521 char *buf = zalloc(blksz); 1522 if (!buf) 1523 return -ENOMEM; 1524 struct ext4_extent_header *ext_block; 1525 struct ext4_extent *extent; 1526 int i = -1; 1527 ext_block = 1528 ext4fs_get_extent_block(ext4fs_root, buf, 1529 (struct ext4_extent_header *) 1530 inode->b.blocks.dir_blocks, 1531 fileblock, log2_blksz); 1532 if (!ext_block) { 1533 printf("invalid extent block\n"); 1534 free(buf); 1535 return -EINVAL; 1536 } 1537 1538 extent = (struct ext4_extent *)(ext_block + 1); 1539 1540 do { 1541 i++; 1542 if (i >= le16_to_cpu(ext_block->eh_entries)) 1543 break; 1544 } while (fileblock >= le32_to_cpu(extent[i].ee_block)); 1545 if (--i >= 0) { 1546 fileblock -= le32_to_cpu(extent[i].ee_block); 1547 if (fileblock >= le16_to_cpu(extent[i].ee_len)) { 1548 free(buf); 1549 return 0; 1550 } 1551 1552 start = le16_to_cpu(extent[i].ee_start_hi); 1553 start = (start << 32) + 1554 le32_to_cpu(extent[i].ee_start_lo); 1555 free(buf); 1556 return fileblock + start; 1557 } 1558 1559 printf("Extent Error\n"); 1560 free(buf); 1561 return -1; 1562 } 1563 1564 /* Direct blocks. */ 1565 if (fileblock < INDIRECT_BLOCKS) 1566 blknr = le32_to_cpu(inode->b.blocks.dir_blocks[fileblock]); 1567 1568 /* Indirect. */ 1569 else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4))) { 1570 if (ext4fs_indir1_block == NULL) { 1571 ext4fs_indir1_block = zalloc(blksz); 1572 if (ext4fs_indir1_block == NULL) { 1573 printf("** SI ext2fs read block (indir 1)" 1574 "malloc failed. **\n"); 1575 return -1; 1576 } 1577 ext4fs_indir1_size = blksz; 1578 ext4fs_indir1_blkno = -1; 1579 } 1580 if (blksz != ext4fs_indir1_size) { 1581 free(ext4fs_indir1_block); 1582 ext4fs_indir1_block = NULL; 1583 ext4fs_indir1_size = 0; 1584 ext4fs_indir1_blkno = -1; 1585 ext4fs_indir1_block = zalloc(blksz); 1586 if (ext4fs_indir1_block == NULL) { 1587 printf("** SI ext2fs read block (indir 1):" 1588 "malloc failed. **\n"); 1589 return -1; 1590 } 1591 ext4fs_indir1_size = blksz; 1592 } 1593 if ((le32_to_cpu(inode->b.blocks.indir_block) << 1594 log2_blksz) != ext4fs_indir1_blkno) { 1595 status = 1596 ext4fs_devread((lbaint_t)le32_to_cpu 1597 (inode->b.blocks. 1598 indir_block) << log2_blksz, 0, 1599 blksz, (char *)ext4fs_indir1_block); 1600 if (status == 0) { 1601 printf("** SI ext2fs read block (indir 1)" 1602 "failed. **\n"); 1603 return 0; 1604 } 1605 ext4fs_indir1_blkno = 1606 le32_to_cpu(inode->b.blocks. 1607 indir_block) << log2_blksz; 1608 } 1609 blknr = le32_to_cpu(ext4fs_indir1_block 1610 [fileblock - INDIRECT_BLOCKS]); 1611 } 1612 /* Double indirect. */ 1613 else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4 * 1614 (blksz / 4 + 1)))) { 1615 1616 long int perblock = blksz / 4; 1617 long int rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4); 1618 1619 if (ext4fs_indir1_block == NULL) { 1620 ext4fs_indir1_block = zalloc(blksz); 1621 if (ext4fs_indir1_block == NULL) { 1622 printf("** DI ext2fs read block (indir 2 1)" 1623 "malloc failed. **\n"); 1624 return -1; 1625 } 1626 ext4fs_indir1_size = blksz; 1627 ext4fs_indir1_blkno = -1; 1628 } 1629 if (blksz != ext4fs_indir1_size) { 1630 free(ext4fs_indir1_block); 1631 ext4fs_indir1_block = NULL; 1632 ext4fs_indir1_size = 0; 1633 ext4fs_indir1_blkno = -1; 1634 ext4fs_indir1_block = zalloc(blksz); 1635 if (ext4fs_indir1_block == NULL) { 1636 printf("** DI ext2fs read block (indir 2 1)" 1637 "malloc failed. **\n"); 1638 return -1; 1639 } 1640 ext4fs_indir1_size = blksz; 1641 } 1642 if ((le32_to_cpu(inode->b.blocks.double_indir_block) << 1643 log2_blksz) != ext4fs_indir1_blkno) { 1644 status = 1645 ext4fs_devread((lbaint_t)le32_to_cpu 1646 (inode->b.blocks. 1647 double_indir_block) << log2_blksz, 1648 0, blksz, 1649 (char *)ext4fs_indir1_block); 1650 if (status == 0) { 1651 printf("** DI ext2fs read block (indir 2 1)" 1652 "failed. **\n"); 1653 return -1; 1654 } 1655 ext4fs_indir1_blkno = 1656 le32_to_cpu(inode->b.blocks.double_indir_block) << 1657 log2_blksz; 1658 } 1659 1660 if (ext4fs_indir2_block == NULL) { 1661 ext4fs_indir2_block = zalloc(blksz); 1662 if (ext4fs_indir2_block == NULL) { 1663 printf("** DI ext2fs read block (indir 2 2)" 1664 "malloc failed. **\n"); 1665 return -1; 1666 } 1667 ext4fs_indir2_size = blksz; 1668 ext4fs_indir2_blkno = -1; 1669 } 1670 if (blksz != ext4fs_indir2_size) { 1671 free(ext4fs_indir2_block); 1672 ext4fs_indir2_block = NULL; 1673 ext4fs_indir2_size = 0; 1674 ext4fs_indir2_blkno = -1; 1675 ext4fs_indir2_block = zalloc(blksz); 1676 if (ext4fs_indir2_block == NULL) { 1677 printf("** DI ext2fs read block (indir 2 2)" 1678 "malloc failed. **\n"); 1679 return -1; 1680 } 1681 ext4fs_indir2_size = blksz; 1682 } 1683 if ((le32_to_cpu(ext4fs_indir1_block[rblock / perblock]) << 1684 log2_blksz) != ext4fs_indir2_blkno) { 1685 status = ext4fs_devread((lbaint_t)le32_to_cpu 1686 (ext4fs_indir1_block 1687 [rblock / 1688 perblock]) << log2_blksz, 0, 1689 blksz, 1690 (char *)ext4fs_indir2_block); 1691 if (status == 0) { 1692 printf("** DI ext2fs read block (indir 2 2)" 1693 "failed. **\n"); 1694 return -1; 1695 } 1696 ext4fs_indir2_blkno = 1697 le32_to_cpu(ext4fs_indir1_block[rblock 1698 / 1699 perblock]) << 1700 log2_blksz; 1701 } 1702 blknr = le32_to_cpu(ext4fs_indir2_block[rblock % perblock]); 1703 } 1704 /* Tripple indirect. */ 1705 else { 1706 rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4 + 1707 (blksz / 4 * blksz / 4)); 1708 perblock_child = blksz / 4; 1709 perblock_parent = ((blksz / 4) * (blksz / 4)); 1710 1711 if (ext4fs_indir1_block == NULL) { 1712 ext4fs_indir1_block = zalloc(blksz); 1713 if (ext4fs_indir1_block == NULL) { 1714 printf("** TI ext2fs read block (indir 2 1)" 1715 "malloc failed. **\n"); 1716 return -1; 1717 } 1718 ext4fs_indir1_size = blksz; 1719 ext4fs_indir1_blkno = -1; 1720 } 1721 if (blksz != ext4fs_indir1_size) { 1722 free(ext4fs_indir1_block); 1723 ext4fs_indir1_block = NULL; 1724 ext4fs_indir1_size = 0; 1725 ext4fs_indir1_blkno = -1; 1726 ext4fs_indir1_block = zalloc(blksz); 1727 if (ext4fs_indir1_block == NULL) { 1728 printf("** TI ext2fs read block (indir 2 1)" 1729 "malloc failed. **\n"); 1730 return -1; 1731 } 1732 ext4fs_indir1_size = blksz; 1733 } 1734 if ((le32_to_cpu(inode->b.blocks.triple_indir_block) << 1735 log2_blksz) != ext4fs_indir1_blkno) { 1736 status = ext4fs_devread 1737 ((lbaint_t) 1738 le32_to_cpu(inode->b.blocks.triple_indir_block) 1739 << log2_blksz, 0, blksz, 1740 (char *)ext4fs_indir1_block); 1741 if (status == 0) { 1742 printf("** TI ext2fs read block (indir 2 1)" 1743 "failed. **\n"); 1744 return -1; 1745 } 1746 ext4fs_indir1_blkno = 1747 le32_to_cpu(inode->b.blocks.triple_indir_block) << 1748 log2_blksz; 1749 } 1750 1751 if (ext4fs_indir2_block == NULL) { 1752 ext4fs_indir2_block = zalloc(blksz); 1753 if (ext4fs_indir2_block == NULL) { 1754 printf("** TI ext2fs read block (indir 2 2)" 1755 "malloc failed. **\n"); 1756 return -1; 1757 } 1758 ext4fs_indir2_size = blksz; 1759 ext4fs_indir2_blkno = -1; 1760 } 1761 if (blksz != ext4fs_indir2_size) { 1762 free(ext4fs_indir2_block); 1763 ext4fs_indir2_block = NULL; 1764 ext4fs_indir2_size = 0; 1765 ext4fs_indir2_blkno = -1; 1766 ext4fs_indir2_block = zalloc(blksz); 1767 if (ext4fs_indir2_block == NULL) { 1768 printf("** TI ext2fs read block (indir 2 2)" 1769 "malloc failed. **\n"); 1770 return -1; 1771 } 1772 ext4fs_indir2_size = blksz; 1773 } 1774 if ((le32_to_cpu(ext4fs_indir1_block[rblock / 1775 perblock_parent]) << 1776 log2_blksz) 1777 != ext4fs_indir2_blkno) { 1778 status = ext4fs_devread((lbaint_t)le32_to_cpu 1779 (ext4fs_indir1_block 1780 [rblock / 1781 perblock_parent]) << 1782 log2_blksz, 0, blksz, 1783 (char *)ext4fs_indir2_block); 1784 if (status == 0) { 1785 printf("** TI ext2fs read block (indir 2 2)" 1786 "failed. **\n"); 1787 return -1; 1788 } 1789 ext4fs_indir2_blkno = 1790 le32_to_cpu(ext4fs_indir1_block[rblock / 1791 perblock_parent]) 1792 << log2_blksz; 1793 } 1794 1795 if (ext4fs_indir3_block == NULL) { 1796 ext4fs_indir3_block = zalloc(blksz); 1797 if (ext4fs_indir3_block == NULL) { 1798 printf("** TI ext2fs read block (indir 2 2)" 1799 "malloc failed. **\n"); 1800 return -1; 1801 } 1802 ext4fs_indir3_size = blksz; 1803 ext4fs_indir3_blkno = -1; 1804 } 1805 if (blksz != ext4fs_indir3_size) { 1806 free(ext4fs_indir3_block); 1807 ext4fs_indir3_block = NULL; 1808 ext4fs_indir3_size = 0; 1809 ext4fs_indir3_blkno = -1; 1810 ext4fs_indir3_block = zalloc(blksz); 1811 if (ext4fs_indir3_block == NULL) { 1812 printf("** TI ext2fs read block (indir 2 2)" 1813 "malloc failed. **\n"); 1814 return -1; 1815 } 1816 ext4fs_indir3_size = blksz; 1817 } 1818 if ((le32_to_cpu(ext4fs_indir2_block[rblock 1819 / 1820 perblock_child]) << 1821 log2_blksz) != ext4fs_indir3_blkno) { 1822 status = 1823 ext4fs_devread((lbaint_t)le32_to_cpu 1824 (ext4fs_indir2_block 1825 [(rblock / perblock_child) 1826 % (blksz / 4)]) << log2_blksz, 0, 1827 blksz, (char *)ext4fs_indir3_block); 1828 if (status == 0) { 1829 printf("** TI ext2fs read block (indir 2 2)" 1830 "failed. **\n"); 1831 return -1; 1832 } 1833 ext4fs_indir3_blkno = 1834 le32_to_cpu(ext4fs_indir2_block[(rblock / 1835 perblock_child) % 1836 (blksz / 1837 4)]) << 1838 log2_blksz; 1839 } 1840 1841 blknr = le32_to_cpu(ext4fs_indir3_block 1842 [rblock % perblock_child]); 1843 } 1844 debug("read_allocated_block %ld\n", blknr); 1845 1846 return blknr; 1847 } 1848 1849 /** 1850 * ext4fs_reinit_global() - Reinitialize values of ext4 write implementation's 1851 * global pointers 1852 * 1853 * This function assures that for a file with the same name but different size 1854 * the sequential store on the ext4 filesystem will be correct. 1855 * 1856 * In this function the global data, responsible for internal representation 1857 * of the ext4 data are initialized to the reset state. Without this, during 1858 * replacement of the smaller file with the bigger truncation of new file was 1859 * performed. 1860 */ 1861 void ext4fs_reinit_global(void) 1862 { 1863 if (ext4fs_indir1_block != NULL) { 1864 free(ext4fs_indir1_block); 1865 ext4fs_indir1_block = NULL; 1866 ext4fs_indir1_size = 0; 1867 ext4fs_indir1_blkno = -1; 1868 } 1869 if (ext4fs_indir2_block != NULL) { 1870 free(ext4fs_indir2_block); 1871 ext4fs_indir2_block = NULL; 1872 ext4fs_indir2_size = 0; 1873 ext4fs_indir2_blkno = -1; 1874 } 1875 if (ext4fs_indir3_block != NULL) { 1876 free(ext4fs_indir3_block); 1877 ext4fs_indir3_block = NULL; 1878 ext4fs_indir3_size = 0; 1879 ext4fs_indir3_blkno = -1; 1880 } 1881 } 1882 void ext4fs_close(void) 1883 { 1884 if ((ext4fs_file != NULL) && (ext4fs_root != NULL)) { 1885 ext4fs_free_node(ext4fs_file, &ext4fs_root->diropen); 1886 ext4fs_file = NULL; 1887 } 1888 if (ext4fs_root != NULL) { 1889 free(ext4fs_root); 1890 ext4fs_root = NULL; 1891 } 1892 1893 ext4fs_reinit_global(); 1894 } 1895 1896 int ext4fs_iterate_dir(struct ext2fs_node *dir, char *name, 1897 struct ext2fs_node **fnode, int *ftype) 1898 { 1899 unsigned int fpos = 0; 1900 int status; 1901 loff_t actread; 1902 struct ext2fs_node *diro = (struct ext2fs_node *) dir; 1903 1904 #ifdef DEBUG 1905 if (name != NULL) 1906 printf("Iterate dir %s\n", name); 1907 #endif /* of DEBUG */ 1908 if (!diro->inode_read) { 1909 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode); 1910 if (status == 0) 1911 return 0; 1912 } 1913 /* Search the file. */ 1914 while (fpos < le32_to_cpu(diro->inode.size)) { 1915 struct ext2_dirent dirent; 1916 1917 status = ext4fs_read_file(diro, fpos, 1918 sizeof(struct ext2_dirent), 1919 (char *)&dirent, &actread); 1920 if (status < 0) 1921 return 0; 1922 1923 if (dirent.direntlen == 0) { 1924 printf("Failed to iterate over directory %s\n", name); 1925 return 0; 1926 } 1927 1928 if (dirent.namelen != 0) { 1929 char filename[dirent.namelen + 1]; 1930 struct ext2fs_node *fdiro; 1931 int type = FILETYPE_UNKNOWN; 1932 1933 status = ext4fs_read_file(diro, 1934 fpos + 1935 sizeof(struct ext2_dirent), 1936 dirent.namelen, filename, 1937 &actread); 1938 if (status < 0) 1939 return 0; 1940 1941 fdiro = zalloc(sizeof(struct ext2fs_node)); 1942 if (!fdiro) 1943 return 0; 1944 1945 fdiro->data = diro->data; 1946 fdiro->ino = le32_to_cpu(dirent.inode); 1947 1948 filename[dirent.namelen] = '\0'; 1949 1950 if (dirent.filetype != FILETYPE_UNKNOWN) { 1951 fdiro->inode_read = 0; 1952 1953 if (dirent.filetype == FILETYPE_DIRECTORY) 1954 type = FILETYPE_DIRECTORY; 1955 else if (dirent.filetype == FILETYPE_SYMLINK) 1956 type = FILETYPE_SYMLINK; 1957 else if (dirent.filetype == FILETYPE_REG) 1958 type = FILETYPE_REG; 1959 } else { 1960 status = ext4fs_read_inode(diro->data, 1961 le32_to_cpu 1962 (dirent.inode), 1963 &fdiro->inode); 1964 if (status == 0) { 1965 free(fdiro); 1966 return 0; 1967 } 1968 fdiro->inode_read = 1; 1969 1970 if ((le16_to_cpu(fdiro->inode.mode) & 1971 FILETYPE_INO_MASK) == 1972 FILETYPE_INO_DIRECTORY) { 1973 type = FILETYPE_DIRECTORY; 1974 } else if ((le16_to_cpu(fdiro->inode.mode) 1975 & FILETYPE_INO_MASK) == 1976 FILETYPE_INO_SYMLINK) { 1977 type = FILETYPE_SYMLINK; 1978 } else if ((le16_to_cpu(fdiro->inode.mode) 1979 & FILETYPE_INO_MASK) == 1980 FILETYPE_INO_REG) { 1981 type = FILETYPE_REG; 1982 } 1983 } 1984 #ifdef DEBUG 1985 printf("iterate >%s<\n", filename); 1986 #endif /* of DEBUG */ 1987 if ((name != NULL) && (fnode != NULL) 1988 && (ftype != NULL)) { 1989 if (strcmp(filename, name) == 0) { 1990 *ftype = type; 1991 *fnode = fdiro; 1992 return 1; 1993 } 1994 } else { 1995 if (fdiro->inode_read == 0) { 1996 status = ext4fs_read_inode(diro->data, 1997 le32_to_cpu( 1998 dirent.inode), 1999 &fdiro->inode); 2000 if (status == 0) { 2001 free(fdiro); 2002 return 0; 2003 } 2004 fdiro->inode_read = 1; 2005 } 2006 switch (type) { 2007 case FILETYPE_DIRECTORY: 2008 printf("<DIR> "); 2009 break; 2010 case FILETYPE_SYMLINK: 2011 printf("<SYM> "); 2012 break; 2013 case FILETYPE_REG: 2014 printf(" "); 2015 break; 2016 default: 2017 printf("< ? > "); 2018 break; 2019 } 2020 printf("%10u %s\n", 2021 le32_to_cpu(fdiro->inode.size), 2022 filename); 2023 } 2024 free(fdiro); 2025 } 2026 fpos += le16_to_cpu(dirent.direntlen); 2027 } 2028 return 0; 2029 } 2030 2031 static char *ext4fs_read_symlink(struct ext2fs_node *node) 2032 { 2033 char *symlink; 2034 struct ext2fs_node *diro = node; 2035 int status; 2036 loff_t actread; 2037 2038 if (!diro->inode_read) { 2039 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode); 2040 if (status == 0) 2041 return NULL; 2042 } 2043 symlink = zalloc(le32_to_cpu(diro->inode.size) + 1); 2044 if (!symlink) 2045 return NULL; 2046 2047 if (le32_to_cpu(diro->inode.size) < sizeof(diro->inode.b.symlink)) { 2048 strncpy(symlink, diro->inode.b.symlink, 2049 le32_to_cpu(diro->inode.size)); 2050 } else { 2051 status = ext4fs_read_file(diro, 0, 2052 le32_to_cpu(diro->inode.size), 2053 symlink, &actread); 2054 if ((status < 0) || (actread == 0)) { 2055 free(symlink); 2056 return NULL; 2057 } 2058 } 2059 symlink[le32_to_cpu(diro->inode.size)] = '\0'; 2060 return symlink; 2061 } 2062 2063 static int ext4fs_find_file1(const char *currpath, 2064 struct ext2fs_node *currroot, 2065 struct ext2fs_node **currfound, int *foundtype) 2066 { 2067 char fpath[strlen(currpath) + 1]; 2068 char *name = fpath; 2069 char *next; 2070 int status; 2071 int type = FILETYPE_DIRECTORY; 2072 struct ext2fs_node *currnode = currroot; 2073 struct ext2fs_node *oldnode = currroot; 2074 2075 strncpy(fpath, currpath, strlen(currpath) + 1); 2076 2077 /* Remove all leading slashes. */ 2078 while (*name == '/') 2079 name++; 2080 2081 if (!*name) { 2082 *currfound = currnode; 2083 return 1; 2084 } 2085 2086 for (;;) { 2087 int found; 2088 2089 /* Extract the actual part from the pathname. */ 2090 next = strchr(name, '/'); 2091 if (next) { 2092 /* Remove all leading slashes. */ 2093 while (*next == '/') 2094 *(next++) = '\0'; 2095 } 2096 2097 if (type != FILETYPE_DIRECTORY) { 2098 ext4fs_free_node(currnode, currroot); 2099 return 0; 2100 } 2101 2102 oldnode = currnode; 2103 2104 /* Iterate over the directory. */ 2105 found = ext4fs_iterate_dir(currnode, name, &currnode, &type); 2106 if (found == 0) 2107 return 0; 2108 2109 if (found == -1) 2110 break; 2111 2112 /* Read in the symlink and follow it. */ 2113 if (type == FILETYPE_SYMLINK) { 2114 char *symlink; 2115 2116 /* Test if the symlink does not loop. */ 2117 if (++symlinknest == 8) { 2118 ext4fs_free_node(currnode, currroot); 2119 ext4fs_free_node(oldnode, currroot); 2120 return 0; 2121 } 2122 2123 symlink = ext4fs_read_symlink(currnode); 2124 ext4fs_free_node(currnode, currroot); 2125 2126 if (!symlink) { 2127 ext4fs_free_node(oldnode, currroot); 2128 return 0; 2129 } 2130 2131 debug("Got symlink >%s<\n", symlink); 2132 2133 if (symlink[0] == '/') { 2134 ext4fs_free_node(oldnode, currroot); 2135 oldnode = &ext4fs_root->diropen; 2136 } 2137 2138 /* Lookup the node the symlink points to. */ 2139 status = ext4fs_find_file1(symlink, oldnode, 2140 &currnode, &type); 2141 2142 free(symlink); 2143 2144 if (status == 0) { 2145 ext4fs_free_node(oldnode, currroot); 2146 return 0; 2147 } 2148 } 2149 2150 ext4fs_free_node(oldnode, currroot); 2151 2152 /* Found the node! */ 2153 if (!next || *next == '\0') { 2154 *currfound = currnode; 2155 *foundtype = type; 2156 return 1; 2157 } 2158 name = next; 2159 } 2160 return -1; 2161 } 2162 2163 int ext4fs_find_file(const char *path, struct ext2fs_node *rootnode, 2164 struct ext2fs_node **foundnode, int expecttype) 2165 { 2166 int status; 2167 int foundtype = FILETYPE_DIRECTORY; 2168 2169 symlinknest = 0; 2170 if (!path) 2171 return 0; 2172 2173 status = ext4fs_find_file1(path, rootnode, foundnode, &foundtype); 2174 if (status == 0) 2175 return 0; 2176 2177 /* Check if the node that was found was of the expected type. */ 2178 if ((expecttype == FILETYPE_REG) && (foundtype != expecttype)) 2179 return 0; 2180 else if ((expecttype == FILETYPE_DIRECTORY) 2181 && (foundtype != expecttype)) 2182 return 0; 2183 2184 return 1; 2185 } 2186 2187 int ext4fs_open(const char *filename, loff_t *len) 2188 { 2189 struct ext2fs_node *fdiro = NULL; 2190 int status; 2191 2192 if (ext4fs_root == NULL) 2193 return -1; 2194 2195 ext4fs_file = NULL; 2196 status = ext4fs_find_file(filename, &ext4fs_root->diropen, &fdiro, 2197 FILETYPE_REG); 2198 if (status == 0) 2199 goto fail; 2200 2201 if (!fdiro->inode_read) { 2202 status = ext4fs_read_inode(fdiro->data, fdiro->ino, 2203 &fdiro->inode); 2204 if (status == 0) 2205 goto fail; 2206 } 2207 *len = le32_to_cpu(fdiro->inode.size); 2208 ext4fs_file = fdiro; 2209 2210 return 0; 2211 fail: 2212 ext4fs_free_node(fdiro, &ext4fs_root->diropen); 2213 2214 return -1; 2215 } 2216 2217 int ext4fs_mount(unsigned part_length) 2218 { 2219 struct ext2_data *data; 2220 int status; 2221 struct ext_filesystem *fs = get_fs(); 2222 data = zalloc(SUPERBLOCK_SIZE); 2223 if (!data) 2224 return 0; 2225 2226 /* Read the superblock. */ 2227 status = ext4_read_superblock((char *)&data->sblock); 2228 2229 if (status == 0) 2230 goto fail; 2231 2232 /* Make sure this is an ext2 filesystem. */ 2233 if (le16_to_cpu(data->sblock.magic) != EXT2_MAGIC) 2234 goto fail; 2235 2236 /* 2237 * The 64bit feature was enabled when metadata_csum was enabled 2238 * and we do not support metadata_csum (and cannot reliably find 2239 * files when it is set. Refuse to mount. 2240 */ 2241 if (le32_to_cpu(data->sblock.feature_incompat) & EXT4_FEATURE_INCOMPAT_64BIT) { 2242 printf("Unsupported feature found (64bit, possibly metadata_csum), not mounting\n"); 2243 goto fail; 2244 } 2245 2246 if (le32_to_cpu(data->sblock.revision_level) == 0) 2247 fs->inodesz = 128; 2248 else 2249 fs->inodesz = le16_to_cpu(data->sblock.inode_size); 2250 2251 debug("EXT2 rev %d, inode_size %d\n", 2252 le32_to_cpu(data->sblock.revision_level), fs->inodesz); 2253 2254 data->diropen.data = data; 2255 data->diropen.ino = 2; 2256 data->diropen.inode_read = 1; 2257 data->inode = &data->diropen.inode; 2258 2259 status = ext4fs_read_inode(data, 2, data->inode); 2260 if (status == 0) 2261 goto fail; 2262 2263 ext4fs_root = data; 2264 2265 return 1; 2266 fail: 2267 printf("Failed to mount ext2 filesystem...\n"); 2268 free(data); 2269 ext4fs_root = NULL; 2270 2271 return 0; 2272 } 2273