fs/ext4/ext4_common.c

   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 <malloc.h>
  26 #include <stddef.h>
  27 #include <linux/stat.h>
  28 #include <linux/time.h>
  29 #include <asm/byteorder.h>
  30 #include "ext4_common.h"
  31
  32 struct ext2_data *ext4fs_root;
  33 struct ext2fs_node *ext4fs_file;
  34 uint32_t *ext4fs_indir1_block;
  35 int ext4fs_indir1_size;
  36 int ext4fs_indir1_blkno = -1;
  37 uint32_t *ext4fs_indir2_block;
  38 int ext4fs_indir2_size;
  39 int ext4fs_indir2_blkno = -1;
  40
  41 uint32_t *ext4fs_indir3_block;
  42 int ext4fs_indir3_size;
  43 int ext4fs_indir3_blkno = -1;
  44 struct ext2_inode *g_parent_inode;
  45 static int symlinknest;
  46
  47 #if defined(CONFIG_EXT4_WRITE)
  48 uint32_t ext4fs_div_roundup(uint32_t size, uint32_t n)
  49 {
  50         uint32_t res = size / n;
  51         if (res * n != size)
  52                 res++;
  53
  54         return res;
  55 }
  56
  57 void put_ext4(uint64_t off, void *buf, uint32_t size)
  58 {
  59         uint64_t startblock;
  60         uint64_t remainder;
  61         unsigned char *temp_ptr = NULL;
  62         struct ext_filesystem *fs = get_fs();
  63         int log2blksz = fs->dev_desc->log2blksz;
  64         ALLOC_CACHE_ALIGN_BUFFER(unsigned char, sec_buf, fs->dev_desc->blksz);
  65
  66         startblock = off >> log2blksz;
  67         startblock += part_offset;
  68         remainder = off & (uint64_t)(fs->dev_desc->blksz - 1);
  69
  70         if (fs->dev_desc == NULL)
  71                 return;
  72
  73         if ((startblock + (size >> log2blksz)) >
  74             (part_offset + fs->total_sect)) {
  75                 printf("part_offset is " LBAFU "\n", part_offset);
  76                 printf("total_sector is %llu\n", fs->total_sect);
  77                 printf("error: overflow occurs\n");
  78                 return;
  79         }
  80
  81         if (remainder) {
  82                 if (fs->dev_desc->block_read) {
  83                         fs->dev_desc->block_read(fs->dev_desc->dev,
  84                                                  startblock, 1, sec_buf);
  85                         temp_ptr = sec_buf;
  86                         memcpy((temp_ptr + remainder),
  87                                (unsigned char *)buf, size);
  88                         fs->dev_desc->block_write(fs->dev_desc->dev,
  89                                                   startblock, 1, sec_buf);
  90                 }
  91         } else {
  92                 if (size >> log2blksz != 0) {
  93                         fs->dev_desc->block_write(fs->dev_desc->dev,
  94                                                   startblock,
  95                                                   size >> log2blksz,
  96                                                   (unsigned long *)buf);
  97                 } else {
  98                         fs->dev_desc->block_read(fs->dev_desc->dev,
  99                                                  startblock, 1, sec_buf);
 100                         temp_ptr = sec_buf;
 101                         memcpy(temp_ptr, buf, size);
 102                         fs->dev_desc->block_write(fs->dev_desc->dev,
 103                                                   startblock, 1,
 104                                                   (unsigned long *)sec_buf);
 105                 }
 106         }
 107 }
 108
 109 static int _get_new_inode_no(unsigned char *buffer)
 110 {
 111         struct ext_filesystem *fs = get_fs();
 112         unsigned char input;
 113         int operand, status;
 114         int count = 1;
 115         int j = 0;
 116
 117         /* get the blocksize of the filesystem */
 118         unsigned char *ptr = buffer;
 119         while (*ptr == 255) {
 120                 ptr++;
 121                 count += 8;
 122                 if (count > ext4fs_root->sblock.inodes_per_group)
 123                         return -1;
 124         }
 125
 126         for (j = 0; j < fs->blksz; j++) {
 127                 input = *ptr;
 128                 int i = 0;
 129                 while (i <= 7) {
 130                         operand = 1 << i;
 131                         status = input & operand;
 132                         if (status) {
 133                                 i++;
 134                                 count++;
 135                         } else {
 136                                 *ptr |= operand;
 137                                 return count;
 138                         }
 139                 }
 140                 ptr = ptr + 1;
 141         }
 142
 143         return -1;
 144 }
 145
 146 static int _get_new_blk_no(unsigned char *buffer)
 147 {
 148         unsigned char input;
 149         int operand, status;
 150         int count = 0;
 151         int j = 0;
 152         unsigned char *ptr = buffer;
 153         struct ext_filesystem *fs = get_fs();
 154
 155         if (fs->blksz != 1024)
 156                 count = 0;
 157         else
 158                 count = 1;
 159
 160         while (*ptr == 255) {
 161                 ptr++;
 162                 count += 8;
 163                 if (count == (fs->blksz * 8))
 164                         return -1;
 165         }
 166
 167         for (j = 0; j < fs->blksz; j++) {
 168                 input = *ptr;
 169                 int i = 0;
 170                 while (i <= 7) {
 171                         operand = 1 << i;
 172                         status = input & operand;
 173                         if (status) {
 174                                 i++;
 175                                 count++;
 176                         } else {
 177                                 *ptr |= operand;
 178                                 return count;
 179                         }
 180                 }
 181                 ptr = ptr + 1;
 182         }
 183
 184         return -1;
 185 }
 186
 187 int ext4fs_set_block_bmap(long int blockno, unsigned char *buffer, int index)
 188 {
 189         int i, remainder, status;
 190         unsigned char *ptr = buffer;
 191         unsigned char operand;
 192         i = blockno / 8;
 193         remainder = blockno % 8;
 194         int blocksize = EXT2_BLOCK_SIZE(ext4fs_root);
 195
 196         i = i - (index * blocksize);
 197         if (blocksize != 1024) {
 198                 ptr = ptr + i;
 199                 operand = 1 << remainder;
 200                 status = *ptr & operand;
 201                 if (status)
 202                         return -1;
 203
 204                 *ptr = *ptr | operand;
 205                 return 0;
 206         } else {
 207                 if (remainder == 0) {
 208                         ptr = ptr + i - 1;
 209                         operand = (1 << 7);
 210                 } else {
 211                         ptr = ptr + i;
 212                         operand = (1 << (remainder - 1));
 213                 }
 214                 status = *ptr & operand;
 215                 if (status)
 216                         return -1;
 217
 218                 *ptr = *ptr | operand;
 219                 return 0;
 220         }
 221 }
 222
 223 void ext4fs_reset_block_bmap(long int blockno, unsigned char *buffer, int index)
 224 {
 225         int i, remainder, status;
 226         unsigned char *ptr = buffer;
 227         unsigned char operand;
 228         i = blockno / 8;
 229         remainder = blockno % 8;
 230         int blocksize = EXT2_BLOCK_SIZE(ext4fs_root);
 231
 232         i = i - (index * blocksize);
 233         if (blocksize != 1024) {
 234                 ptr = ptr + i;
 235                 operand = (1 << remainder);
 236                 status = *ptr & operand;
 237                 if (status)
 238                         *ptr = *ptr & ~(operand);
 239         } else {
 240                 if (remainder == 0) {
 241                         ptr = ptr + i - 1;
 242                         operand = (1 << 7);
 243                 } else {
 244                         ptr = ptr + i;
 245                         operand = (1 << (remainder - 1));
 246                 }
 247                 status = *ptr & operand;
 248                 if (status)
 249                         *ptr = *ptr & ~(operand);
 250         }
 251 }
 252
 253 int ext4fs_set_inode_bmap(int inode_no, unsigned char *buffer, int index)
 254 {
 255         int i, remainder, status;
 256         unsigned char *ptr = buffer;
 257         unsigned char operand;
 258
 259         inode_no -= (index * ext4fs_root->sblock.inodes_per_group);
 260         i = inode_no / 8;
 261         remainder = inode_no % 8;
 262         if (remainder == 0) {
 263                 ptr = ptr + i - 1;
 264                 operand = (1 << 7);
 265         } else {
 266                 ptr = ptr + i;
 267                 operand = (1 << (remainder - 1));
 268         }
 269         status = *ptr & operand;
 270         if (status)
 271                 return -1;
 272
 273         *ptr = *ptr | operand;
 274
 275         return 0;
 276 }
 277
 278 void ext4fs_reset_inode_bmap(int inode_no, unsigned char *buffer, int index)
 279 {
 280         int i, remainder, status;
 281         unsigned char *ptr = buffer;
 282         unsigned char operand;
 283
 284         inode_no -= (index * ext4fs_root->sblock.inodes_per_group);
 285         i = inode_no / 8;
 286         remainder = inode_no % 8;
 287         if (remainder == 0) {
 288                 ptr = ptr + i - 1;
 289                 operand = (1 << 7);
 290         } else {
 291                 ptr = ptr + i;
 292                 operand = (1 << (remainder - 1));
 293         }
 294         status = *ptr & operand;
 295         if (status)
 296                 *ptr = *ptr & ~(operand);
 297 }
 298
 299 int ext4fs_checksum_update(unsigned int i)
 300 {
 301         struct ext2_block_group *desc;
 302         struct ext_filesystem *fs = get_fs();
 303         __u16 crc = 0;
 304
 305         desc = (struct ext2_block_group *)&fs->bgd[i];
 306         if (fs->sb->feature_ro_compat & EXT4_FEATURE_RO_COMPAT_GDT_CSUM) {
 307                 int offset = offsetof(struct ext2_block_group, bg_checksum);
 308
 309                 crc = ext2fs_crc16(~0, fs->sb->unique_id,
 310                                    sizeof(fs->sb->unique_id));
 311                 crc = ext2fs_crc16(crc, &i, sizeof(i));
 312                 crc = ext2fs_crc16(crc, desc, offset);
 313                 offset += sizeof(desc->bg_checksum);    /* skip checksum */
 314                 assert(offset == sizeof(*desc));
 315         }
 316
 317         return crc;
 318 }
 319
 320 static int check_void_in_dentry(struct ext2_dirent *dir, char *filename)
 321 {
 322         int dentry_length;
 323         int sizeof_void_space;
 324         int new_entry_byte_reqd;
 325         short padding_factor = 0;
 326
 327         if (dir->namelen % 4 != 0)
 328                 padding_factor = 4 - (dir->namelen % 4);
 329
 330         dentry_length = sizeof(struct ext2_dirent) +
 331                         dir->namelen + padding_factor;
 332         sizeof_void_space = dir->direntlen - dentry_length;
 333         if (sizeof_void_space == 0)
 334                 return 0;
 335
 336         padding_factor = 0;
 337         if (strlen(filename) % 4 != 0)
 338                 padding_factor = 4 - (strlen(filename) % 4);
 339
 340         new_entry_byte_reqd = strlen(filename) +
 341             sizeof(struct ext2_dirent) + padding_factor;
 342         if (sizeof_void_space >= new_entry_byte_reqd) {
 343                 dir->direntlen = dentry_length;
 344                 return sizeof_void_space;
 345         }
 346
 347         return 0;
 348 }
 349
 350 void ext4fs_update_parent_dentry(char *filename, int *p_ino, int file_type)
 351 {
 352         unsigned int *zero_buffer = NULL;
 353         char *root_first_block_buffer = NULL;
 354         int direct_blk_idx;
 355         long int root_blknr;
 356         long int first_block_no_of_root = 0;
 357         long int previous_blknr = -1;
 358         int totalbytes = 0;
 359         short int padding_factor = 0;
 360         unsigned int new_entry_byte_reqd;
 361         unsigned int last_entry_dirlen;
 362         int sizeof_void_space = 0;
 363         int templength = 0;
 364         int inodeno;
 365         int status;
 366         struct ext_filesystem *fs = get_fs();
 367         /* directory entry */
 368         struct ext2_dirent *dir;
 369         char *temp_dir = NULL;
 370
 371         zero_buffer = zalloc(fs->blksz);
 372         if (!zero_buffer) {
 373                 printf("No Memory\n");
 374                 return;
 375         }
 376         root_first_block_buffer = zalloc(fs->blksz);
 377         if (!root_first_block_buffer) {
 378                 free(zero_buffer);
 379                 printf("No Memory\n");
 380                 return;
 381         }
 382 restart:
 383
 384         /* read the block no allocated to a file */
 385         for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS;
 386              direct_blk_idx++) {
 387                 root_blknr = read_allocated_block(g_parent_inode,
 388                                                   direct_blk_idx);
 389                 if (root_blknr == 0) {
 390                         first_block_no_of_root = previous_blknr;
 391                         break;
 392                 }
 393                 previous_blknr = root_blknr;
 394         }
 395
 396         status = ext4fs_devread((lbaint_t)first_block_no_of_root
 397                                 * fs->sect_perblk,
 398                                 0, fs->blksz, root_first_block_buffer);
 399         if (status == 0)
 400                 goto fail;
 401
 402         if (ext4fs_log_journal(root_first_block_buffer, first_block_no_of_root))
 403                 goto fail;
 404         dir = (struct ext2_dirent *)root_first_block_buffer;
 405         totalbytes = 0;
 406         while (dir->direntlen > 0) {
 407                 /*
 408                  * blocksize-totalbytes because last directory length
 409                  * i.e. dir->direntlen is free availble space in the
 410                  * block that means  it is a last entry of directory
 411                  * entry
 412                  */
 413
 414                 /* traversing the each directory entry */
 415                 if (fs->blksz - totalbytes == dir->direntlen) {
 416                         if (strlen(filename) % 4 != 0)
 417                                 padding_factor = 4 - (strlen(filename) % 4);
 418
 419                         new_entry_byte_reqd = strlen(filename) +
 420                             sizeof(struct ext2_dirent) + padding_factor;
 421                         padding_factor = 0;
 422                         /*
 423                          * update last directory entry length to its
 424                          * length because we are creating new directory
 425                          * entry
 426                          */
 427                         if (dir->namelen % 4 != 0)
 428                                 padding_factor = 4 - (dir->namelen % 4);
 429
 430                         last_entry_dirlen = dir->namelen +
 431                             sizeof(struct ext2_dirent) + padding_factor;
 432                         if ((fs->blksz - totalbytes - last_entry_dirlen) <
 433                                 new_entry_byte_reqd) {
 434                                 printf("1st Block Full:Allocate new block\n");
 435
 436                                 if (direct_blk_idx == INDIRECT_BLOCKS - 1) {
 437                                         printf("Directory exceeds limit\n");
 438                                         goto fail;
 439                                 }
 440                                 g_parent_inode->b.blocks.dir_blocks
 441                                     [direct_blk_idx] = ext4fs_get_new_blk_no();
 442                                 if (g_parent_inode->b.blocks.dir_blocks
 443                                         [direct_blk_idx] == -1) {
 444                                         printf("no block left to assign\n");
 445                                         goto fail;
 446                                 }
 447                                 put_ext4(((uint64_t)
 448                                           ((uint64_t)g_parent_inode->b.
 449                                            blocks.dir_blocks[direct_blk_idx] *
 450                                            (uint64_t)fs->blksz)), zero_buffer, fs->blksz);
 451                                 g_parent_inode->size =
 452                                     g_parent_inode->size + fs->blksz;
 453                                 g_parent_inode->blockcnt =
 454                                     g_parent_inode->blockcnt + fs->sect_perblk;
 455                                 if (ext4fs_put_metadata
 456                                     (root_first_block_buffer,
 457                                      first_block_no_of_root))
 458                                         goto fail;
 459                                 goto restart;
 460                         }
 461                         dir->direntlen = last_entry_dirlen;
 462                         break;
 463                 }
 464
 465                 templength = dir->direntlen;
 466                 totalbytes = totalbytes + templength;
 467                 sizeof_void_space = check_void_in_dentry(dir, filename);
 468                 if (sizeof_void_space)
 469                         break;
 470
 471                 dir = (struct ext2_dirent *)((char *)dir + templength);
 472         }
 473
 474         /* make a pointer ready for creating next directory entry */
 475         templength = dir->direntlen;
 476         totalbytes = totalbytes + templength;
 477         dir = (struct ext2_dirent *)((char *)dir + templength);
 478
 479         /* get the next available inode number */
 480         inodeno = ext4fs_get_new_inode_no();
 481         if (inodeno == -1) {
 482                 printf("no inode left to assign\n");
 483                 goto fail;
 484         }
 485         dir->inode = inodeno;
 486         if (sizeof_void_space)
 487                 dir->direntlen = sizeof_void_space;
 488         else
 489                 dir->direntlen = fs->blksz - totalbytes;
 490
 491         dir->namelen = strlen(filename);
 492         dir->filetype = FILETYPE_REG;   /* regular file */
 493         temp_dir = (char *)dir;
 494         temp_dir = temp_dir + sizeof(struct ext2_dirent);
 495         memcpy(temp_dir, filename, strlen(filename));
 496
 497         *p_ino = inodeno;
 498
 499         /* update or write  the 1st block of root inode */
 500         if (ext4fs_put_metadata(root_first_block_buffer,
 501                                 first_block_no_of_root))
 502                 goto fail;
 503
 504 fail:
 505         free(zero_buffer);
 506         free(root_first_block_buffer);
 507 }
 508
 509 static int search_dir(struct ext2_inode *parent_inode, char *dirname)
 510 {
 511         int status;
 512         int inodeno;
 513         int totalbytes;
 514         int templength;
 515         int direct_blk_idx;
 516         long int blknr;
 517         int found = 0;
 518         char *ptr = NULL;
 519         unsigned char *block_buffer = NULL;
 520         struct ext2_dirent *dir = NULL;
 521         struct ext2_dirent *previous_dir = NULL;
 522         struct ext_filesystem *fs = get_fs();
 523
 524         /* read the block no allocated to a file */
 525         for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS;
 526                 direct_blk_idx++) {
 527                 blknr = read_allocated_block(parent_inode, direct_blk_idx);
 528                 if (blknr == 0)
 529                         goto fail;
 530
 531                 /* read the blocks of parenet inode */
 532                 block_buffer = zalloc(fs->blksz);
 533                 if (!block_buffer)
 534                         goto fail;
 535
 536                 status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk,
 537                                         0, fs->blksz, (char *)block_buffer);
 538                 if (status == 0)
 539                         goto fail;
 540
 541                 dir = (struct ext2_dirent *)block_buffer;
 542                 ptr = (char *)dir;
 543                 totalbytes = 0;
 544                 while (dir->direntlen >= 0) {
 545                         /*
 546                          * blocksize-totalbytes because last directory
 547                          * length i.e.,*dir->direntlen is free availble
 548                          * space in the block that means
 549                          * it is a last entry of directory entry
 550                          */
 551                         if (strlen(dirname) == dir->namelen) {
 552                                 if (strncmp(dirname, ptr +
 553                                         sizeof(struct ext2_dirent),
 554                                         dir->namelen) == 0) {
 555                                         previous_dir->direntlen +=
 556                                                         dir->direntlen;
 557                                         inodeno = dir->inode;
 558                                         dir->inode = 0;
 559                                         found = 1;
 560                                         break;
 561                                 }
 562                         }
 563
 564                         if (fs->blksz - totalbytes == dir->direntlen)
 565                                 break;
 566
 567                         /* traversing the each directory entry */
 568                         templength = dir->direntlen;
 569                         totalbytes = totalbytes + templength;
 570                         previous_dir = dir;
 571                         dir = (struct ext2_dirent *)((char *)dir + templength);
 572                         ptr = (char *)dir;
 573                 }
 574
 575                 if (found == 1) {
 576                         free(block_buffer);
 577                         block_buffer = NULL;
 578                         return inodeno;
 579                 }
 580
 581                 free(block_buffer);
 582                 block_buffer = NULL;
 583         }
 584
 585 fail:
 586         free(block_buffer);
 587
 588         return -1;
 589 }
 590
 591 static int find_dir_depth(char *dirname)
 592 {
 593         char *token = strtok(dirname, "/");
 594         int count = 0;
 595         while (token != NULL) {
 596                 token = strtok(NULL, "/");
 597                 count++;
 598         }
 599         return count + 1 + 1;
 600         /*
 601          * for example  for string /home/temp
 602          * depth=home(1)+temp(1)+1 extra for NULL;
 603          * so count is 4;
 604          */
 605 }
 606
 607 static int parse_path(char **arr, char *dirname)
 608 {
 609         char *token = strtok(dirname, "/");
 610         int i = 0;
 611
 612         /* add root */
 613         arr[i] = zalloc(strlen("/") + 1);
 614         if (!arr[i])
 615                 return -ENOMEM;
 616
 617         arr[i++] = "/";
 618
 619         /* add each path entry after root */
 620         while (token != NULL) {
 621                 arr[i] = zalloc(strlen(token) + 1);
 622                 if (!arr[i])
 623                         return -ENOMEM;
 624                 memcpy(arr[i++], token, strlen(token));
 625                 token = strtok(NULL, "/");
 626         }
 627         arr[i] = NULL;
 628
 629         return 0;
 630 }
 631
 632 int ext4fs_iget(int inode_no, struct ext2_inode *inode)
 633 {
 634         if (ext4fs_read_inode(ext4fs_root, inode_no, inode) == 0)
 635                 return -1;
 636
 637         return 0;
 638 }
 639
 640 /*
 641  * Function: ext4fs_get_parent_inode_num
 642  * Return Value: inode Number of the parent directory of  file/Directory to be
 643  * created
 644  * dirname : Input parmater, input path name of the file/directory to be created
 645  * dname : Output parameter, to be filled with the name of the directory
 646  * extracted from dirname
 647  */
 648 int ext4fs_get_parent_inode_num(const char *dirname, char *dname, int flags)
 649 {
 650         int i;
 651         int depth = 0;
 652         int matched_inode_no;
 653         int result_inode_no = -1;
 654         char **ptr = NULL;
 655         char *depth_dirname = NULL;
 656         char *parse_dirname = NULL;
 657         struct ext2_inode *parent_inode = NULL;
 658         struct ext2_inode *first_inode = NULL;
 659         struct ext2_inode temp_inode;
 660
 661         if (*dirname != '/') {
 662                 printf("Please supply Absolute path\n");
 663                 return -1;
 664         }
 665
 666         /* TODO: input validation make equivalent to linux */
 667         depth_dirname = zalloc(strlen(dirname) + 1);
 668         if (!depth_dirname)
 669                 return -ENOMEM;
 670
 671         memcpy(depth_dirname, dirname, strlen(dirname));
 672         depth = find_dir_depth(depth_dirname);
 673         parse_dirname = zalloc(strlen(dirname) + 1);
 674         if (!parse_dirname)
 675                 goto fail;
 676         memcpy(parse_dirname, dirname, strlen(dirname));
 677
 678         /* allocate memory for each directory level */
 679         ptr = zalloc((depth) * sizeof(char *));
 680         if (!ptr)
 681                 goto fail;
 682         if (parse_path(ptr, parse_dirname))
 683                 goto fail;
 684         parent_inode = zalloc(sizeof(struct ext2_inode));
 685         if (!parent_inode)
 686                 goto fail;
 687         first_inode = zalloc(sizeof(struct ext2_inode));
 688         if (!first_inode)
 689                 goto fail;
 690         memcpy(parent_inode, ext4fs_root->inode, sizeof(struct ext2_inode));
 691         memcpy(first_inode, parent_inode, sizeof(struct ext2_inode));
 692         if (flags & F_FILE)
 693                 result_inode_no = EXT2_ROOT_INO;
 694         for (i = 1; i < depth; i++) {
 695                 matched_inode_no = search_dir(parent_inode, ptr[i]);
 696                 if (matched_inode_no == -1) {
 697                         if (ptr[i + 1] == NULL && i == 1) {
 698                                 result_inode_no = EXT2_ROOT_INO;
 699                                 goto end;
 700                         } else {
 701                                 if (ptr[i + 1] == NULL)
 702                                         break;
 703                                 printf("Invalid path\n");
 704                                 result_inode_no = -1;
 705                                 goto fail;
 706                         }
 707                 } else {
 708                         if (ptr[i + 1] != NULL) {
 709                                 memset(parent_inode, '\0',
 710                                        sizeof(struct ext2_inode));
 711                                 if (ext4fs_iget(matched_inode_no,
 712                                                 parent_inode)) {
 713                                         result_inode_no = -1;
 714                                         goto fail;
 715                                 }
 716                                 result_inode_no = matched_inode_no;
 717                         } else {
 718                                 break;
 719                         }
 720                 }
 721         }
 722
 723 end:
 724         if (i == 1)
 725                 matched_inode_no = search_dir(first_inode, ptr[i]);
 726         else
 727                 matched_inode_no = search_dir(parent_inode, ptr[i]);
 728
 729         if (matched_inode_no != -1) {
 730                 ext4fs_iget(matched_inode_no, &temp_inode);
 731                 if (temp_inode.mode & S_IFDIR) {
 732                         printf("It is a Directory\n");
 733                         result_inode_no = -1;
 734                         goto fail;
 735                 }
 736         }
 737
 738         if (strlen(ptr[i]) > 256) {
 739                 result_inode_no = -1;
 740                 goto fail;
 741         }
 742         memcpy(dname, ptr[i], strlen(ptr[i]));
 743
 744 fail:
 745         free(depth_dirname);
 746         free(parse_dirname);
 747         free(ptr);
 748         free(parent_inode);
 749         free(first_inode);
 750
 751         return result_inode_no;
 752 }
 753
 754 static int check_filename(char *filename, unsigned int blknr)
 755 {
 756         unsigned int first_block_no_of_root;
 757         int totalbytes = 0;
 758         int templength = 0;
 759         int status, inodeno;
 760         int found = 0;
 761         char *root_first_block_buffer = NULL;
 762         char *root_first_block_addr = NULL;
 763         struct ext2_dirent *dir = NULL;
 764         struct ext2_dirent *previous_dir = NULL;
 765         char *ptr = NULL;
 766         struct ext_filesystem *fs = get_fs();
 767
 768         /* get the first block of root */
 769         first_block_no_of_root = blknr;
 770         root_first_block_buffer = zalloc(fs->blksz);
 771         if (!root_first_block_buffer)
 772                 return -ENOMEM;
 773         root_first_block_addr = root_first_block_buffer;
 774         status = ext4fs_devread((lbaint_t)first_block_no_of_root *
 775                                 fs->sect_perblk, 0,
 776                                 fs->blksz, root_first_block_buffer);
 777         if (status == 0)
 778                 goto fail;
 779
 780         if (ext4fs_log_journal(root_first_block_buffer, first_block_no_of_root))
 781                 goto fail;
 782         dir = (struct ext2_dirent *)root_first_block_buffer;
 783         ptr = (char *)dir;
 784         totalbytes = 0;
 785         while (dir->direntlen >= 0) {
 786                 /*
 787                  * blocksize-totalbytes because last
 788                  * directory length i.e., *dir->direntlen
 789                  * is free availble space in the block that
 790                  * means it is a last entry of directory entry
 791                  */
 792                 if (strlen(filename) == dir->namelen) {
 793                         if (strncmp(filename, ptr + sizeof(struct ext2_dirent),
 794                                 dir->namelen) == 0) {
 795                                 printf("file found deleting\n");
 796                                 previous_dir->direntlen += dir->direntlen;
 797                                 inodeno = dir->inode;
 798                                 dir->inode = 0;
 799                                 found = 1;
 800                                 break;
 801                         }
 802                 }
 803
 804                 if (fs->blksz - totalbytes == dir->direntlen)
 805                         break;
 806
 807                 /* traversing the each directory entry */
 808                 templength = dir->direntlen;
 809                 totalbytes = totalbytes + templength;
 810                 previous_dir = dir;
 811                 dir = (struct ext2_dirent *)((char *)dir + templength);
 812                 ptr = (char *)dir;
 813         }
 814
 815
 816         if (found == 1) {
 817                 if (ext4fs_put_metadata(root_first_block_addr,
 818                                         first_block_no_of_root))
 819                         goto fail;
 820                 return inodeno;
 821         }
 822 fail:
 823         free(root_first_block_buffer);
 824
 825         return -1;
 826 }
 827
 828 int ext4fs_filename_check(char *filename)
 829 {
 830         short direct_blk_idx = 0;
 831         long int blknr = -1;
 832         int inodeno = -1;
 833
 834         /* read the block no allocated to a file */
 835         for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS;
 836                 direct_blk_idx++) {
 837                 blknr = read_allocated_block(g_parent_inode, direct_blk_idx);
 838                 if (blknr == 0)
 839                         break;
 840                 inodeno = check_filename(filename, blknr);
 841                 if (inodeno != -1)
 842                         return inodeno;
 843         }
 844
 845         return -1;
 846 }
 847
 848 long int ext4fs_get_new_blk_no(void)
 849 {
 850         short i;
 851         short status;
 852         int remainder;
 853         unsigned int bg_idx;
 854         static int prev_bg_bitmap_index = -1;
 855         unsigned int blk_per_grp = ext4fs_root->sblock.blocks_per_group;
 856         struct ext_filesystem *fs = get_fs();
 857         char *journal_buffer = zalloc(fs->blksz);
 858         char *zero_buffer = zalloc(fs->blksz);
 859         if (!journal_buffer || !zero_buffer)
 860                 goto fail;
 861         struct ext2_block_group *bgd = (struct ext2_block_group *)fs->gdtable;
 862
 863         if (fs->first_pass_bbmap == 0) {
 864                 for (i = 0; i < fs->no_blkgrp; i++) {
 865                         if (bgd[i].free_blocks) {
 866                                 if (bgd[i].bg_flags & EXT4_BG_BLOCK_UNINIT) {
 867                                         put_ext4(((uint64_t) ((uint64_t)bgd[i].block_id *
 868                                                               (uint64_t)fs->blksz)),
 869                                                  zero_buffer, fs->blksz);
 870                                         bgd[i].bg_flags =
 871                                             bgd[i].
 872                                             bg_flags & ~EXT4_BG_BLOCK_UNINIT;
 873                                         memcpy(fs->blk_bmaps[i], zero_buffer,
 874                                                fs->blksz);
 875                                 }
 876                                 fs->curr_blkno =
 877                                     _get_new_blk_no(fs->blk_bmaps[i]);
 878                                 if (fs->curr_blkno == -1)
 879                                         /* if block bitmap is completely fill */
 880                                         continue;
 881                                 fs->curr_blkno = fs->curr_blkno +
 882                                                 (i * fs->blksz * 8);
 883                                 fs->first_pass_bbmap++;
 884                                 bgd[i].free_blocks--;
 885                                 fs->sb->free_blocks--;
 886                                 status = ext4fs_devread((lbaint_t)
 887                                                         bgd[i].block_id *
 888                                                         fs->sect_perblk, 0,
 889                                                         fs->blksz,
 890                                                         journal_buffer);
 891                                 if (status == 0)
 892                                         goto fail;
 893                                 if (ext4fs_log_journal(journal_buffer,
 894                                                         bgd[i].block_id))
 895                                         goto fail;
 896                                 goto success;
 897                         } else {
 898                                 debug("no space left on block group %d\n", i);
 899                         }
 900                 }
 901
 902                 goto fail;
 903         } else {
 904 restart:
 905                 fs->curr_blkno++;
 906                 /* get the blockbitmap index respective to blockno */
 907                 bg_idx = fs->curr_blkno / blk_per_grp;
 908                 if (fs->blksz == 1024) {
 909                         remainder = fs->curr_blkno % blk_per_grp;
 910                         if (!remainder)
 911                                 bg_idx--;
 912                 }
 913
 914                 /*
 915                  * To skip completely filled block group bitmaps
 916                  * Optimize the block allocation
 917                  */
 918                 if (bg_idx >= fs->no_blkgrp)
 919                         goto fail;
 920
 921                 if (bgd[bg_idx].free_blocks == 0) {
 922                         debug("block group %u is full. Skipping\n", bg_idx);
 923                         fs->curr_blkno = fs->curr_blkno + blk_per_grp;
 924                         fs->curr_blkno--;
 925                         goto restart;
 926                 }
 927
 928                 if (bgd[bg_idx].bg_flags & EXT4_BG_BLOCK_UNINIT) {
 929                         memset(zero_buffer, '\0', fs->blksz);
 930                         put_ext4(((uint64_t) ((uint64_t)bgd[bg_idx].block_id *
 931                                         (uint64_t)fs->blksz)), zero_buffer, fs->blksz);
 932                         memcpy(fs->blk_bmaps[bg_idx], zero_buffer, fs->blksz);
 933                         bgd[bg_idx].bg_flags = bgd[bg_idx].bg_flags &
 934                                                 ~EXT4_BG_BLOCK_UNINIT;
 935                 }
 936
 937                 if (ext4fs_set_block_bmap(fs->curr_blkno, fs->blk_bmaps[bg_idx],
 938                                    bg_idx) != 0) {
 939                         debug("going for restart for the block no %ld %u\n",
 940                               fs->curr_blkno, bg_idx);
 941                         goto restart;
 942                 }
 943
 944                 /* journal backup */
 945                 if (prev_bg_bitmap_index != bg_idx) {
 946                         memset(journal_buffer, '\0', fs->blksz);
 947                         status = ext4fs_devread((lbaint_t)bgd[bg_idx].block_id
 948                                                 * fs->sect_perblk,
 949                                                 0, fs->blksz, journal_buffer);
 950                         if (status == 0)
 951                                 goto fail;
 952                         if (ext4fs_log_journal(journal_buffer,
 953                                                 bgd[bg_idx].block_id))
 954                                 goto fail;
 955
 956                         prev_bg_bitmap_index = bg_idx;
 957                 }
 958                 bgd[bg_idx].free_blocks--;
 959                 fs->sb->free_blocks--;
 960                 goto success;
 961         }
 962 success:
 963         free(journal_buffer);
 964         free(zero_buffer);
 965
 966         return fs->curr_blkno;
 967 fail:
 968         free(journal_buffer);
 969         free(zero_buffer);
 970
 971         return -1;
 972 }
 973
 974 int ext4fs_get_new_inode_no(void)
 975 {
 976         short i;
 977         short status;
 978         unsigned int ibmap_idx;
 979         static int prev_inode_bitmap_index = -1;
 980         unsigned int inodes_per_grp = ext4fs_root->sblock.inodes_per_group;
 981         struct ext_filesystem *fs = get_fs();
 982         char *journal_buffer = zalloc(fs->blksz);
 983         char *zero_buffer = zalloc(fs->blksz);
 984         if (!journal_buffer || !zero_buffer)
 985                 goto fail;
 986         struct ext2_block_group *bgd = (struct ext2_block_group *)fs->gdtable;
 987
 988         if (fs->first_pass_ibmap == 0) {
 989                 for (i = 0; i < fs->no_blkgrp; i++) {
 990                         if (bgd[i].free_inodes) {
 991                                 if (bgd[i].bg_itable_unused !=
 992                                                 bgd[i].free_inodes)
 993                                         bgd[i].bg_itable_unused =
 994                                                 bgd[i].free_inodes;
 995                                 if (bgd[i].bg_flags & EXT4_BG_INODE_UNINIT) {
 996                                         put_ext4(((uint64_t)
 997                                                   ((uint64_t)bgd[i].inode_id *
 998                                                         (uint64_t)fs->blksz)),
 999                                                  zero_buffer, fs->blksz);
1000                                         bgd[i].bg_flags = bgd[i].bg_flags &
1001                                                         ~EXT4_BG_INODE_UNINIT;
1002                                         memcpy(fs->inode_bmaps[i],
1003                                                zero_buffer, fs->blksz);
1004                                 }
1005                                 fs->curr_inode_no =
1006                                     _get_new_inode_no(fs->inode_bmaps[i]);
1007                                 if (fs->curr_inode_no == -1)
1008                                         /* if block bitmap is completely fill */
1009                                         continue;
1010                                 fs->curr_inode_no = fs->curr_inode_no +
1011                                                         (i * inodes_per_grp);
1012                                 fs->first_pass_ibmap++;
1013                                 bgd[i].free_inodes--;
1014                                 bgd[i].bg_itable_unused--;
1015                                 fs->sb->free_inodes--;
1016                                 status = ext4fs_devread((lbaint_t)
1017                                                         bgd[i].inode_id *
1018                                                         fs->sect_perblk, 0,
1019                                                         fs->blksz,
1020                                                         journal_buffer);
1021                                 if (status == 0)
1022                                         goto fail;
1023                                 if (ext4fs_log_journal(journal_buffer,
1024                                                         bgd[i].inode_id))
1025                                         goto fail;
1026                                 goto success;
1027                         } else
1028                                 debug("no inode left on block group %d\n", i);
1029                 }
1030                 goto fail;
1031         } else {
1032 restart:
1033                 fs->curr_inode_no++;
1034                 /* get the blockbitmap index respective to blockno */
1035                 ibmap_idx = fs->curr_inode_no / inodes_per_grp;
1036                 if (bgd[ibmap_idx].bg_flags & EXT4_BG_INODE_UNINIT) {
1037                         memset(zero_buffer, '\0', fs->blksz);
1038                         put_ext4(((uint64_t) ((uint64_t)bgd[ibmap_idx].inode_id *
1039                                               (uint64_t)fs->blksz)), zero_buffer,
1040                                  fs->blksz);
1041                         bgd[ibmap_idx].bg_flags =
1042                             bgd[ibmap_idx].bg_flags & ~EXT4_BG_INODE_UNINIT;
1043                         memcpy(fs->inode_bmaps[ibmap_idx], zero_buffer,
1044                                 fs->blksz);
1045                 }
1046
1047                 if (ext4fs_set_inode_bmap(fs->curr_inode_no,
1048                                           fs->inode_bmaps[ibmap_idx],
1049                                           ibmap_idx) != 0) {
1050                         debug("going for restart for the block no %d %u\n",
1051                               fs->curr_inode_no, ibmap_idx);
1052                         goto restart;
1053                 }
1054
1055                 /* journal backup */
1056                 if (prev_inode_bitmap_index != ibmap_idx) {
1057                         memset(journal_buffer, '\0', fs->blksz);
1058                         status = ext4fs_devread((lbaint_t)
1059                                                 bgd[ibmap_idx].inode_id
1060                                                 * fs->sect_perblk,
1061                                                 0, fs->blksz, journal_buffer);
1062                         if (status == 0)
1063                                 goto fail;
1064                         if (ext4fs_log_journal(journal_buffer,
1065                                                 bgd[ibmap_idx].inode_id))
1066                                 goto fail;
1067                         prev_inode_bitmap_index = ibmap_idx;
1068                 }
1069                 if (bgd[ibmap_idx].bg_itable_unused !=
1070                                 bgd[ibmap_idx].free_inodes)
1071                         bgd[ibmap_idx].bg_itable_unused =
1072                                         bgd[ibmap_idx].free_inodes;
1073                 bgd[ibmap_idx].free_inodes--;
1074                 bgd[ibmap_idx].bg_itable_unused--;
1075                 fs->sb->free_inodes--;
1076                 goto success;
1077         }
1078
1079 success:
1080         free(journal_buffer);
1081         free(zero_buffer);
1082
1083         return fs->curr_inode_no;
1084 fail:
1085         free(journal_buffer);
1086         free(zero_buffer);
1087
1088         return -1;
1089
1090 }
1091
1092
1093 static void alloc_single_indirect_block(struct ext2_inode *file_inode,
1094                                         unsigned int *total_remaining_blocks,
1095                                         unsigned int *no_blks_reqd)
1096 {
1097         short i;
1098         short status;
1099         long int actual_block_no;
1100         long int si_blockno;
1101         /* si :single indirect */
1102         unsigned int *si_buffer = NULL;
1103         unsigned int *si_start_addr = NULL;
1104         struct ext_filesystem *fs = get_fs();
1105
1106         if (*total_remaining_blocks != 0) {
1107                 si_buffer = zalloc(fs->blksz);
1108                 if (!si_buffer) {
1109                         printf("No Memory\n");
1110                         return;
1111                 }
1112                 si_start_addr = si_buffer;
1113                 si_blockno = ext4fs_get_new_blk_no();
1114                 if (si_blockno == -1) {
1115                         printf("no block left to assign\n");
1116                         goto fail;
1117                 }
1118                 (*no_blks_reqd)++;
1119                 debug("SIPB %ld: %u\n", si_blockno, *total_remaining_blocks);
1120
1121                 status = ext4fs_devread((lbaint_t)si_blockno * fs->sect_perblk,
1122                                         0, fs->blksz, (char *)si_buffer);
1123                 memset(si_buffer, '\0', fs->blksz);
1124                 if (status == 0)
1125                         goto fail;
1126
1127                 for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
1128                         actual_block_no = ext4fs_get_new_blk_no();
1129                         if (actual_block_no == -1) {
1130                                 printf("no block left to assign\n");
1131                                 goto fail;
1132                         }
1133                         *si_buffer = actual_block_no;
1134                         debug("SIAB %u: %u\n", *si_buffer,
1135                                 *total_remaining_blocks);
1136
1137                         si_buffer++;
1138                         (*total_remaining_blocks)--;
1139                         if (*total_remaining_blocks == 0)
1140                                 break;
1141                 }
1142
1143                 /* write the block to disk */
1144                 put_ext4(((uint64_t) ((uint64_t)si_blockno * (uint64_t)fs->blksz)),
1145                          si_start_addr, fs->blksz);
1146                 file_inode->b.blocks.indir_block = si_blockno;
1147         }
1148 fail:
1149         free(si_start_addr);
1150 }
1151
1152 static void alloc_double_indirect_block(struct ext2_inode *file_inode,
1153                                         unsigned int *total_remaining_blocks,
1154                                         unsigned int *no_blks_reqd)
1155 {
1156         short i;
1157         short j;
1158         short status;
1159         long int actual_block_no;
1160         /* di:double indirect */
1161         long int di_blockno_parent;
1162         long int di_blockno_child;
1163         unsigned int *di_parent_buffer = NULL;
1164         unsigned int *di_child_buff = NULL;
1165         unsigned int *di_block_start_addr = NULL;
1166         unsigned int *di_child_buff_start = NULL;
1167         struct ext_filesystem *fs = get_fs();
1168
1169         if (*total_remaining_blocks != 0) {
1170                 /* double indirect parent block connecting to inode */
1171                 di_blockno_parent = ext4fs_get_new_blk_no();
1172                 if (di_blockno_parent == -1) {
1173                         printf("no block left to assign\n");
1174                         goto fail;
1175                 }
1176                 di_parent_buffer = zalloc(fs->blksz);
1177                 if (!di_parent_buffer)
1178                         goto fail;
1179
1180                 di_block_start_addr = di_parent_buffer;
1181                 (*no_blks_reqd)++;
1182                 debug("DIPB %ld: %u\n", di_blockno_parent,
1183                       *total_remaining_blocks);
1184
1185                 status = ext4fs_devread((lbaint_t)di_blockno_parent *
1186                                         fs->sect_perblk, 0,
1187                                         fs->blksz, (char *)di_parent_buffer);
1188
1189                 if (!status) {
1190                         printf("%s: Device read error!\n", __func__);
1191                         goto fail;
1192                 }
1193                 memset(di_parent_buffer, '\0', fs->blksz);
1194
1195                 /*
1196                  * start:for each double indirect parent
1197                  * block create one more block
1198                  */
1199                 for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
1200                         di_blockno_child = ext4fs_get_new_blk_no();
1201                         if (di_blockno_child == -1) {
1202                                 printf("no block left to assign\n");
1203                                 goto fail;
1204                         }
1205                         di_child_buff = zalloc(fs->blksz);
1206                         if (!di_child_buff)
1207                                 goto fail;
1208
1209                         di_child_buff_start = di_child_buff;
1210                         *di_parent_buffer = di_blockno_child;
1211                         di_parent_buffer++;
1212                         (*no_blks_reqd)++;
1213                         debug("DICB %ld: %u\n", di_blockno_child,
1214                               *total_remaining_blocks);
1215
1216                         status = ext4fs_devread((lbaint_t)di_blockno_child *
1217                                                 fs->sect_perblk, 0,
1218                                                 fs->blksz,
1219                                                 (char *)di_child_buff);
1220
1221                         if (!status) {
1222                                 printf("%s: Device read error!\n", __func__);
1223                                 goto fail;
1224                         }
1225                         memset(di_child_buff, '\0', fs->blksz);
1226                         /* filling of actual datablocks for each child */
1227                         for (j = 0; j < (fs->blksz / sizeof(int)); j++) {
1228                                 actual_block_no = ext4fs_get_new_blk_no();
1229                                 if (actual_block_no == -1) {
1230                                         printf("no block left to assign\n");
1231                                         goto fail;
1232                                 }
1233                                 *di_child_buff = actual_block_no;
1234                                 debug("DIAB %ld: %u\n", actual_block_no,
1235                                       *total_remaining_blocks);
1236
1237                                 di_child_buff++;
1238                                 (*total_remaining_blocks)--;
1239                                 if (*total_remaining_blocks == 0)
1240                                         break;
1241                         }
1242                         /* write the block  table */
1243                         put_ext4(((uint64_t) ((uint64_t)di_blockno_child * (uint64_t)fs->blksz)),
1244                                  di_child_buff_start, fs->blksz);
1245                         free(di_child_buff_start);
1246                         di_child_buff_start = NULL;
1247
1248                         if (*total_remaining_blocks == 0)
1249                                 break;
1250                 }
1251                 put_ext4(((uint64_t) ((uint64_t)di_blockno_parent * (uint64_t)fs->blksz)),
1252                          di_block_start_addr, fs->blksz);
1253                 file_inode->b.blocks.double_indir_block = di_blockno_parent;
1254         }
1255 fail:
1256         free(di_block_start_addr);
1257 }
1258
1259 static void alloc_triple_indirect_block(struct ext2_inode *file_inode,
1260                                         unsigned int *total_remaining_blocks,
1261                                         unsigned int *no_blks_reqd)
1262 {
1263         short i;
1264         short j;
1265         short k;
1266         long int actual_block_no;
1267         /* ti: Triple Indirect */
1268         long int ti_gp_blockno;
1269         long int ti_parent_blockno;
1270         long int ti_child_blockno;
1271         unsigned int *ti_gp_buff = NULL;
1272         unsigned int *ti_parent_buff = NULL;
1273         unsigned int *ti_child_buff = NULL;
1274         unsigned int *ti_gp_buff_start_addr = NULL;
1275         unsigned int *ti_pbuff_start_addr = NULL;
1276         unsigned int *ti_cbuff_start_addr = NULL;
1277         struct ext_filesystem *fs = get_fs();
1278         if (*total_remaining_blocks != 0) {
1279                 /* triple indirect grand parent block connecting to inode */
1280                 ti_gp_blockno = ext4fs_get_new_blk_no();
1281                 if (ti_gp_blockno == -1) {
1282                         printf("no block left to assign\n");
1283                         goto fail;
1284                 }
1285                 ti_gp_buff = zalloc(fs->blksz);
1286                 if (!ti_gp_buff)
1287                         goto fail;
1288
1289                 ti_gp_buff_start_addr = ti_gp_buff;
1290                 (*no_blks_reqd)++;
1291                 debug("TIGPB %ld: %u\n", ti_gp_blockno,
1292                       *total_remaining_blocks);
1293
1294                 /* for each 4 byte grand parent entry create one more block */
1295                 for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
1296                         ti_parent_blockno = ext4fs_get_new_blk_no();
1297                         if (ti_parent_blockno == -1) {
1298                                 printf("no block left to assign\n");
1299                                 goto fail;
1300                         }
1301                         ti_parent_buff = zalloc(fs->blksz);
1302                         if (!ti_parent_buff)
1303                                 goto fail;
1304
1305                         ti_pbuff_start_addr = ti_parent_buff;
1306                         *ti_gp_buff = ti_parent_blockno;
1307                         ti_gp_buff++;
1308                         (*no_blks_reqd)++;
1309                         debug("TIPB %ld: %u\n", ti_parent_blockno,
1310                               *total_remaining_blocks);
1311
1312                         /* for each 4 byte entry parent create one more block */
1313                         for (j = 0; j < (fs->blksz / sizeof(int)); j++) {
1314                                 ti_child_blockno = ext4fs_get_new_blk_no();
1315                                 if (ti_child_blockno == -1) {
1316                                         printf("no block left assign\n");
1317                                         goto fail;
1318                                 }
1319                                 ti_child_buff = zalloc(fs->blksz);
1320                                 if (!ti_child_buff)
1321                                         goto fail;
1322
1323                                 ti_cbuff_start_addr = ti_child_buff;
1324                                 *ti_parent_buff = ti_child_blockno;
1325                                 ti_parent_buff++;
1326                                 (*no_blks_reqd)++;
1327                                 debug("TICB %ld: %u\n", ti_parent_blockno,
1328                                       *total_remaining_blocks);
1329
1330                                 /* fill actual datablocks for each child */
1331                                 for (k = 0; k < (fs->blksz / sizeof(int));
1332                                         k++) {
1333                                         actual_block_no =
1334                                             ext4fs_get_new_blk_no();
1335                                         if (actual_block_no == -1) {
1336                                                 printf("no block left\n");
1337                                                 goto fail;
1338                                         }
1339                                         *ti_child_buff = actual_block_no;
1340                                         debug("TIAB %ld: %u\n", actual_block_no,
1341                                               *total_remaining_blocks);
1342
1343                                         ti_child_buff++;
1344                                         (*total_remaining_blocks)--;
1345                                         if (*total_remaining_blocks == 0)
1346                                                 break;
1347                                 }
1348                                 /* write the child block */
1349                                 put_ext4(((uint64_t) ((uint64_t)ti_child_blockno *
1350                                                       (uint64_t)fs->blksz)),
1351                                          ti_cbuff_start_addr, fs->blksz);
1352                                 free(ti_cbuff_start_addr);
1353
1354                                 if (*total_remaining_blocks == 0)
1355                                         break;
1356                         }
1357                         /* write the parent block */
1358                         put_ext4(((uint64_t) ((uint64_t)ti_parent_blockno * (uint64_t)fs->blksz)),
1359                                  ti_pbuff_start_addr, fs->blksz);
1360                         free(ti_pbuff_start_addr);
1361
1362                         if (*total_remaining_blocks == 0)
1363                                 break;
1364                 }
1365                 /* write the grand parent block */
1366                 put_ext4(((uint64_t) ((uint64_t)ti_gp_blockno * (uint64_t)fs->blksz)),
1367                          ti_gp_buff_start_addr, fs->blksz);
1368                 file_inode->b.blocks.triple_indir_block = ti_gp_blockno;
1369         }
1370 fail:
1371         free(ti_gp_buff_start_addr);
1372 }
1373
1374 void ext4fs_allocate_blocks(struct ext2_inode *file_inode,
1375                                 unsigned int total_remaining_blocks,
1376                                 unsigned int *total_no_of_block)
1377 {
1378         short i;
1379         long int direct_blockno;
1380         unsigned int no_blks_reqd = 0;
1381
1382         /* allocation of direct blocks */
1383         for (i = 0; i < INDIRECT_BLOCKS; i++) {
1384                 direct_blockno = ext4fs_get_new_blk_no();
1385                 if (direct_blockno == -1) {
1386                         printf("no block left to assign\n");
1387                         return;
1388                 }
1389                 file_inode->b.blocks.dir_blocks[i] = direct_blockno;
1390                 debug("DB %ld: %u\n", direct_blockno, total_remaining_blocks);
1391
1392                 total_remaining_blocks--;
1393                 if (total_remaining_blocks == 0)
1394                         break;
1395         }
1396
1397         alloc_single_indirect_block(file_inode, &total_remaining_blocks,
1398                                     &no_blks_reqd);
1399         alloc_double_indirect_block(file_inode, &total_remaining_blocks,
1400                                     &no_blks_reqd);
1401         alloc_triple_indirect_block(file_inode, &total_remaining_blocks,
1402                                     &no_blks_reqd);
1403         *total_no_of_block += no_blks_reqd;
1404 }
1405
1406 #endif
1407
1408 static struct ext4_extent_header *ext4fs_get_extent_block
1409         (struct ext2_data *data, char *buf,
1410                 struct ext4_extent_header *ext_block,
1411                 uint32_t fileblock, int log2_blksz)
1412 {
1413         struct ext4_extent_idx *index;
1414         unsigned long long block;
1415         int blksz = EXT2_BLOCK_SIZE(data);
1416         int i;
1417
1418         while (1) {
1419                 index = (struct ext4_extent_idx *)(ext_block + 1);
1420
1421                 if (le16_to_cpu(ext_block->eh_magic) != EXT4_EXT_MAGIC)
1422                         return 0;
1423
1424                 if (ext_block->eh_depth == 0)
1425                         return ext_block;
1426                 i = -1;
1427                 do {
1428                         i++;
1429                         if (i >= le16_to_cpu(ext_block->eh_entries))
1430                                 break;
1431                 } while (fileblock >= le32_to_cpu(index[i].ei_block));
1432
1433                 if (--i < 0)
1434                         return 0;
1435
1436                 block = le16_to_cpu(index[i].ei_leaf_hi);
1437                 block = (block << 32) + le32_to_cpu(index[i].ei_leaf_lo);
1438
1439                 if (ext4fs_devread((lbaint_t)block << log2_blksz, 0, blksz,
1440                                    buf))
1441                         ext_block = (struct ext4_extent_header *)buf;
1442                 else
1443                         return 0;
1444         }
1445 }
1446
1447 static int ext4fs_blockgroup
1448         (struct ext2_data *data, int group, struct ext2_block_group *blkgrp)
1449 {
1450         long int blkno;
1451         unsigned int blkoff, desc_per_blk;
1452         int log2blksz = get_fs()->dev_desc->log2blksz;
1453
1454         desc_per_blk = EXT2_BLOCK_SIZE(data) / sizeof(struct ext2_block_group);
1455
1456         blkno = __le32_to_cpu(data->sblock.first_data_block) + 1 +
1457                         group / desc_per_blk;
1458         blkoff = (group % desc_per_blk) * sizeof(struct ext2_block_group);
1459
1460         debug("ext4fs read %d group descriptor (blkno %ld blkoff %u)\n",
1461               group, blkno, blkoff);
1462
1463         return ext4fs_devread((lbaint_t)blkno <<
1464                               (LOG2_BLOCK_SIZE(data) - log2blksz),
1465                               blkoff, sizeof(struct ext2_block_group),
1466                               (char *)blkgrp);
1467 }
1468
1469 int ext4fs_read_inode(struct ext2_data *data, int ino, struct ext2_inode *inode)
1470 {
1471         struct ext2_block_group blkgrp;
1472         struct ext2_sblock *sblock = &data->sblock;
1473         struct ext_filesystem *fs = get_fs();
1474         int log2blksz = get_fs()->dev_desc->log2blksz;
1475         int inodes_per_block, status;
1476         long int blkno;
1477         unsigned int blkoff;
1478
1479         /* It is easier to calculate if the first inode is 0. */
1480         ino--;
1481         status = ext4fs_blockgroup(data, ino / __le32_to_cpu
1482                                    (sblock->inodes_per_group), &blkgrp);
1483         if (status == 0)
1484                 return 0;
1485
1486         inodes_per_block = EXT2_BLOCK_SIZE(data) / fs->inodesz;
1487         blkno = __le32_to_cpu(blkgrp.inode_table_id) +
1488             (ino % __le32_to_cpu(sblock->inodes_per_group)) / inodes_per_block;
1489         blkoff = (ino % inodes_per_block) * fs->inodesz;
1490         /* Read the inode. */
1491         status = ext4fs_devread((lbaint_t)blkno << (LOG2_BLOCK_SIZE(data) -
1492                                 log2blksz), blkoff,
1493                                 sizeof(struct ext2_inode), (char *)inode);
1494         if (status == 0)
1495                 return 0;
1496
1497         return 1;
1498 }
1499
1500 long int read_allocated_block(struct ext2_inode *inode, int fileblock)
1501 {
1502         long int blknr;
1503         int blksz;
1504         int log2_blksz;
1505         int status;
1506         long int rblock;
1507         long int perblock_parent;
1508         long int perblock_child;
1509         unsigned long long start;
1510         /* get the blocksize of the filesystem */
1511         blksz = EXT2_BLOCK_SIZE(ext4fs_root);
1512         log2_blksz = LOG2_BLOCK_SIZE(ext4fs_root)
1513                 - get_fs()->dev_desc->log2blksz;
1514
1515         if (le32_to_cpu(inode->flags) & EXT4_EXTENTS_FL) {
1516                 char *buf = zalloc(blksz);
1517                 if (!buf)
1518                         return -ENOMEM;
1519                 struct ext4_extent_header *ext_block;
1520                 struct ext4_extent *extent;
1521                 int i = -1;
1522                 ext_block =
1523                         ext4fs_get_extent_block(ext4fs_root, buf,
1524                                                 (struct ext4_extent_header *)
1525                                                 inode->b.blocks.dir_blocks,
1526                                                 fileblock, log2_blksz);
1527                 if (!ext_block) {
1528                         printf("invalid extent block\n");
1529                         free(buf);
1530                         return -EINVAL;
1531                 }
1532
1533                 extent = (struct ext4_extent *)(ext_block + 1);
1534
1535                 do {
1536                         i++;
1537                         if (i >= le16_to_cpu(ext_block->eh_entries))
1538                                 break;
1539                 } while (fileblock >= le32_to_cpu(extent[i].ee_block));
1540                 if (--i >= 0) {
1541                         fileblock -= le32_to_cpu(extent[i].ee_block);
1542                         if (fileblock >= le16_to_cpu(extent[i].ee_len)) {
1543                                 free(buf);
1544                                 return 0;
1545                         }
1546
1547                         start = le16_to_cpu(extent[i].ee_start_hi);
1548                         start = (start << 32) +
1549                                         le32_to_cpu(extent[i].ee_start_lo);
1550                         free(buf);
1551                         return fileblock + start;
1552                 }
1553
1554                 printf("Extent Error\n");
1555                 free(buf);
1556                 return -1;
1557         }
1558
1559         /* Direct blocks. */
1560         if (fileblock < INDIRECT_BLOCKS)
1561                 blknr = __le32_to_cpu(inode->b.blocks.dir_blocks[fileblock]);
1562
1563         /* Indirect. */
1564         else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4))) {
1565                 if (ext4fs_indir1_block == NULL) {
1566                         ext4fs_indir1_block = zalloc(blksz);
1567                         if (ext4fs_indir1_block == NULL) {
1568                                 printf("** SI ext2fs read block (indir 1)"
1569                                         "malloc failed. **\n");
1570                                 return -1;
1571                         }
1572                         ext4fs_indir1_size = blksz;
1573                         ext4fs_indir1_blkno = -1;
1574                 }
1575                 if (blksz != ext4fs_indir1_size) {
1576                         free(ext4fs_indir1_block);
1577                         ext4fs_indir1_block = NULL;
1578                         ext4fs_indir1_size = 0;
1579                         ext4fs_indir1_blkno = -1;
1580                         ext4fs_indir1_block = zalloc(blksz);
1581                         if (ext4fs_indir1_block == NULL) {
1582                                 printf("** SI ext2fs read block (indir 1):"
1583                                         "malloc failed. **\n");
1584                                 return -1;
1585                         }
1586                         ext4fs_indir1_size = blksz;
1587                 }
1588                 if ((__le32_to_cpu(inode->b.blocks.indir_block) <<
1589                      log2_blksz) != ext4fs_indir1_blkno) {
1590                         status =
1591                             ext4fs_devread((lbaint_t)__le32_to_cpu
1592                                            (inode->b.blocks.
1593                                             indir_block) << log2_blksz, 0,
1594                                            blksz, (char *)ext4fs_indir1_block);
1595                         if (status == 0) {
1596                                 printf("** SI ext2fs read block (indir 1)"
1597                                         "failed. **\n");
1598                                 return 0;
1599                         }
1600                         ext4fs_indir1_blkno =
1601                                 __le32_to_cpu(inode->b.blocks.
1602                                                indir_block) << log2_blksz;
1603                 }
1604                 blknr = __le32_to_cpu(ext4fs_indir1_block
1605                                       [fileblock - INDIRECT_BLOCKS]);
1606         }
1607         /* Double indirect. */
1608         else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4 *
1609                                         (blksz / 4 + 1)))) {
1610
1611                 long int perblock = blksz / 4;
1612                 long int rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4);
1613
1614                 if (ext4fs_indir1_block == NULL) {
1615                         ext4fs_indir1_block = zalloc(blksz);
1616                         if (ext4fs_indir1_block == NULL) {
1617                                 printf("** DI ext2fs read block (indir 2 1)"
1618                                         "malloc failed. **\n");
1619                                 return -1;
1620                         }
1621                         ext4fs_indir1_size = blksz;
1622                         ext4fs_indir1_blkno = -1;
1623                 }
1624                 if (blksz != ext4fs_indir1_size) {
1625                         free(ext4fs_indir1_block);
1626                         ext4fs_indir1_block = NULL;
1627                         ext4fs_indir1_size = 0;
1628                         ext4fs_indir1_blkno = -1;
1629                         ext4fs_indir1_block = zalloc(blksz);
1630                         if (ext4fs_indir1_block == NULL) {
1631                                 printf("** DI ext2fs read block (indir 2 1)"
1632                                         "malloc failed. **\n");
1633                                 return -1;
1634                         }
1635                         ext4fs_indir1_size = blksz;
1636                 }
1637                 if ((__le32_to_cpu(inode->b.blocks.double_indir_block) <<
1638                      log2_blksz) != ext4fs_indir1_blkno) {
1639                         status =
1640                             ext4fs_devread((lbaint_t)__le32_to_cpu
1641                                            (inode->b.blocks.
1642                                             double_indir_block) << log2_blksz,
1643                                            0, blksz,
1644                                            (char *)ext4fs_indir1_block);
1645                         if (status == 0) {
1646                                 printf("** DI ext2fs read block (indir 2 1)"
1647                                         "failed. **\n");
1648                                 return -1;
1649                         }
1650                         ext4fs_indir1_blkno =
1651                             __le32_to_cpu(inode->b.blocks.double_indir_block) <<
1652                             log2_blksz;
1653                 }
1654
1655                 if (ext4fs_indir2_block == NULL) {
1656                         ext4fs_indir2_block = zalloc(blksz);
1657                         if (ext4fs_indir2_block == NULL) {
1658                                 printf("** DI ext2fs read block (indir 2 2)"
1659                                         "malloc failed. **\n");
1660                                 return -1;
1661                         }
1662                         ext4fs_indir2_size = blksz;
1663                         ext4fs_indir2_blkno = -1;
1664                 }
1665                 if (blksz != ext4fs_indir2_size) {
1666                         free(ext4fs_indir2_block);
1667                         ext4fs_indir2_block = NULL;
1668                         ext4fs_indir2_size = 0;
1669                         ext4fs_indir2_blkno = -1;
1670                         ext4fs_indir2_block = zalloc(blksz);
1671                         if (ext4fs_indir2_block == NULL) {
1672                                 printf("** DI ext2fs read block (indir 2 2)"
1673                                         "malloc failed. **\n");
1674                                 return -1;
1675                         }
1676                         ext4fs_indir2_size = blksz;
1677                 }
1678                 if ((__le32_to_cpu(ext4fs_indir1_block[rblock / perblock]) <<
1679                      log2_blksz) != ext4fs_indir2_blkno) {
1680                         status = ext4fs_devread((lbaint_t)__le32_to_cpu
1681                                                 (ext4fs_indir1_block
1682                                                  [rblock /
1683                                                   perblock]) << log2_blksz, 0,
1684                                                 blksz,
1685                                                 (char *)ext4fs_indir2_block);
1686                         if (status == 0) {
1687                                 printf("** DI ext2fs read block (indir 2 2)"
1688                                         "failed. **\n");
1689                                 return -1;
1690                         }
1691                         ext4fs_indir2_blkno =
1692                             __le32_to_cpu(ext4fs_indir1_block[rblock
1693                                                               /
1694                                                               perblock]) <<
1695                             log2_blksz;
1696                 }
1697                 blknr = __le32_to_cpu(ext4fs_indir2_block[rblock % perblock]);
1698         }
1699         /* Tripple indirect. */
1700         else {
1701                 rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4 +
1702                                       (blksz / 4 * blksz / 4));
1703                 perblock_child = blksz / 4;
1704                 perblock_parent = ((blksz / 4) * (blksz / 4));
1705
1706                 if (ext4fs_indir1_block == NULL) {
1707                         ext4fs_indir1_block = zalloc(blksz);
1708                         if (ext4fs_indir1_block == NULL) {
1709                                 printf("** TI ext2fs read block (indir 2 1)"
1710                                         "malloc failed. **\n");
1711                                 return -1;
1712                         }
1713                         ext4fs_indir1_size = blksz;
1714                         ext4fs_indir1_blkno = -1;
1715                 }
1716                 if (blksz != ext4fs_indir1_size) {
1717                         free(ext4fs_indir1_block);
1718                         ext4fs_indir1_block = NULL;
1719                         ext4fs_indir1_size = 0;
1720                         ext4fs_indir1_blkno = -1;
1721                         ext4fs_indir1_block = zalloc(blksz);
1722                         if (ext4fs_indir1_block == NULL) {
1723                                 printf("** TI ext2fs read block (indir 2 1)"
1724                                         "malloc failed. **\n");
1725                                 return -1;
1726                         }
1727                         ext4fs_indir1_size = blksz;
1728                 }
1729                 if ((__le32_to_cpu(inode->b.blocks.triple_indir_block) <<
1730                      log2_blksz) != ext4fs_indir1_blkno) {
1731                         status = ext4fs_devread
1732                             ((lbaint_t)
1733                              __le32_to_cpu(inode->b.blocks.triple_indir_block)
1734                              << log2_blksz, 0, blksz,
1735                              (char *)ext4fs_indir1_block);
1736                         if (status == 0) {
1737                                 printf("** TI ext2fs read block (indir 2 1)"
1738                                         "failed. **\n");
1739                                 return -1;
1740                         }
1741                         ext4fs_indir1_blkno =
1742                             __le32_to_cpu(inode->b.blocks.triple_indir_block) <<
1743                             log2_blksz;
1744                 }
1745
1746                 if (ext4fs_indir2_block == NULL) {
1747                         ext4fs_indir2_block = zalloc(blksz);
1748                         if (ext4fs_indir2_block == NULL) {
1749                                 printf("** TI ext2fs read block (indir 2 2)"
1750                                         "malloc failed. **\n");
1751                                 return -1;
1752                         }
1753                         ext4fs_indir2_size = blksz;
1754                         ext4fs_indir2_blkno = -1;
1755                 }
1756                 if (blksz != ext4fs_indir2_size) {
1757                         free(ext4fs_indir2_block);
1758                         ext4fs_indir2_block = NULL;
1759                         ext4fs_indir2_size = 0;
1760                         ext4fs_indir2_blkno = -1;
1761                         ext4fs_indir2_block = zalloc(blksz);
1762                         if (ext4fs_indir2_block == NULL) {
1763                                 printf("** TI ext2fs read block (indir 2 2)"
1764                                         "malloc failed. **\n");
1765                                 return -1;
1766                         }
1767                         ext4fs_indir2_size = blksz;
1768                 }
1769                 if ((__le32_to_cpu(ext4fs_indir1_block[rblock /
1770                                                        perblock_parent]) <<
1771                      log2_blksz)
1772                     != ext4fs_indir2_blkno) {
1773                         status = ext4fs_devread((lbaint_t)__le32_to_cpu
1774                                                 (ext4fs_indir1_block
1775                                                  [rblock /
1776                                                   perblock_parent]) <<
1777                                                 log2_blksz, 0, blksz,
1778                                                 (char *)ext4fs_indir2_block);
1779                         if (status == 0) {
1780                                 printf("** TI ext2fs read block (indir 2 2)"
1781                                         "failed. **\n");
1782                                 return -1;
1783                         }
1784                         ext4fs_indir2_blkno =
1785                             __le32_to_cpu(ext4fs_indir1_block[rblock /
1786                                                               perblock_parent])
1787                             << log2_blksz;
1788                 }
1789
1790                 if (ext4fs_indir3_block == NULL) {
1791                         ext4fs_indir3_block = zalloc(blksz);
1792                         if (ext4fs_indir3_block == NULL) {
1793                                 printf("** TI ext2fs read block (indir 2 2)"
1794                                         "malloc failed. **\n");
1795                                 return -1;
1796                         }
1797                         ext4fs_indir3_size = blksz;
1798                         ext4fs_indir3_blkno = -1;
1799                 }
1800                 if (blksz != ext4fs_indir3_size) {
1801                         free(ext4fs_indir3_block);
1802                         ext4fs_indir3_block = NULL;
1803                         ext4fs_indir3_size = 0;
1804                         ext4fs_indir3_blkno = -1;
1805                         ext4fs_indir3_block = zalloc(blksz);
1806                         if (ext4fs_indir3_block == NULL) {
1807                                 printf("** TI ext2fs read block (indir 2 2)"
1808                                         "malloc failed. **\n");
1809                                 return -1;
1810                         }
1811                         ext4fs_indir3_size = blksz;
1812                 }
1813                 if ((__le32_to_cpu(ext4fs_indir2_block[rblock
1814                                                        /
1815                                                        perblock_child]) <<
1816                      log2_blksz) != ext4fs_indir3_blkno) {
1817                         status =
1818                             ext4fs_devread((lbaint_t)__le32_to_cpu
1819                                            (ext4fs_indir2_block
1820                                             [(rblock / perblock_child)
1821                                              % (blksz / 4)]) << log2_blksz, 0,
1822                                            blksz, (char *)ext4fs_indir3_block);
1823                         if (status == 0) {
1824                                 printf("** TI ext2fs read block (indir 2 2)"
1825                                        "failed. **\n");
1826                                 return -1;
1827                         }
1828                         ext4fs_indir3_blkno =
1829                             __le32_to_cpu(ext4fs_indir2_block[(rblock /
1830                                                                perblock_child) %
1831                                                               (blksz /
1832                                                                4)]) <<
1833                             log2_blksz;
1834                 }
1835
1836                 blknr = __le32_to_cpu(ext4fs_indir3_block
1837                                       [rblock % perblock_child]);
1838         }
1839         debug("read_allocated_block %ld\n", blknr);
1840
1841         return blknr;
1842 }
1843
1844 /**
1845  * ext4fs_reinit_global() - Reinitialize values of ext4 write implementation's
1846  *                          global pointers
1847  *
1848  * This function assures that for a file with the same name but different size
1849  * the sequential store on the ext4 filesystem will be correct.
1850  *
1851  * In this function the global data, responsible for internal representation
1852  * of the ext4 data are initialized to the reset state. Without this, during
1853  * replacement of the smaller file with the bigger truncation of new file was
1854  * performed.
1855  */
1856 void ext4fs_reinit_global(void)
1857 {
1858         if (ext4fs_indir1_block != NULL) {
1859                 free(ext4fs_indir1_block);
1860                 ext4fs_indir1_block = NULL;
1861                 ext4fs_indir1_size = 0;
1862                 ext4fs_indir1_blkno = -1;
1863         }
1864         if (ext4fs_indir2_block != NULL) {
1865                 free(ext4fs_indir2_block);
1866                 ext4fs_indir2_block = NULL;
1867                 ext4fs_indir2_size = 0;
1868                 ext4fs_indir2_blkno = -1;
1869         }
1870         if (ext4fs_indir3_block != NULL) {
1871                 free(ext4fs_indir3_block);
1872                 ext4fs_indir3_block = NULL;
1873                 ext4fs_indir3_size = 0;
1874                 ext4fs_indir3_blkno = -1;
1875         }
1876 }
1877 void ext4fs_close(void)
1878 {
1879         if ((ext4fs_file != NULL) && (ext4fs_root != NULL)) {
1880                 ext4fs_free_node(ext4fs_file, &ext4fs_root->diropen);
1881                 ext4fs_file = NULL;
1882         }
1883         if (ext4fs_root != NULL) {
1884                 free(ext4fs_root);
1885                 ext4fs_root = NULL;
1886         }
1887
1888         ext4fs_reinit_global();
1889 }
1890
1891 int ext4fs_iterate_dir(struct ext2fs_node *dir, char *name,
1892                                 struct ext2fs_node **fnode, int *ftype)
1893 {
1894         unsigned int fpos = 0;
1895         int status;
1896         struct ext2fs_node *diro = (struct ext2fs_node *) dir;
1897
1898 #ifdef DEBUG
1899         if (name != NULL)
1900                 printf("Iterate dir %s\n", name);
1901 #endif /* of DEBUG */
1902         if (!diro->inode_read) {
1903                 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode);
1904                 if (status == 0)
1905                         return 0;
1906         }
1907         /* Search the file.  */
1908         while (fpos < __le32_to_cpu(diro->inode.size)) {
1909                 struct ext2_dirent dirent;
1910
1911                 status = ext4fs_read_file(diro, fpos,
1912                                            sizeof(struct ext2_dirent),
1913                                            (char *) &dirent);
1914                 if (status < 1)
1915                         return 0;
1916
1917                 if (dirent.namelen != 0) {
1918                         char filename[dirent.namelen + 1];
1919                         struct ext2fs_node *fdiro;
1920                         int type = FILETYPE_UNKNOWN;
1921
1922                         status = ext4fs_read_file(diro,
1923                                                   fpos +
1924                                                   sizeof(struct ext2_dirent),
1925                                                   dirent.namelen, filename);
1926                         if (status < 1)
1927                                 return 0;
1928
1929                         fdiro = zalloc(sizeof(struct ext2fs_node));
1930                         if (!fdiro)
1931                                 return 0;
1932
1933                         fdiro->data = diro->data;
1934                         fdiro->ino = __le32_to_cpu(dirent.inode);
1935
1936                         filename[dirent.namelen] = '\0';
1937
1938                         if (dirent.filetype != FILETYPE_UNKNOWN) {
1939                                 fdiro->inode_read = 0;
1940
1941                                 if (dirent.filetype == FILETYPE_DIRECTORY)
1942                                         type = FILETYPE_DIRECTORY;
1943                                 else if (dirent.filetype == FILETYPE_SYMLINK)
1944                                         type = FILETYPE_SYMLINK;
1945                                 else if (dirent.filetype == FILETYPE_REG)
1946                                         type = FILETYPE_REG;
1947                         } else {
1948                                 status = ext4fs_read_inode(diro->data,
1949                                                            __le32_to_cpu
1950                                                            (dirent.inode),
1951                                                            &fdiro->inode);
1952                                 if (status == 0) {
1953                                         free(fdiro);
1954                                         return 0;
1955                                 }
1956                                 fdiro->inode_read = 1;
1957
1958                                 if ((__le16_to_cpu(fdiro->inode.mode) &
1959                                      FILETYPE_INO_MASK) ==
1960                                     FILETYPE_INO_DIRECTORY) {
1961                                         type = FILETYPE_DIRECTORY;
1962                                 } else if ((__le16_to_cpu(fdiro->inode.mode)
1963                                             & FILETYPE_INO_MASK) ==
1964                                            FILETYPE_INO_SYMLINK) {
1965                                         type = FILETYPE_SYMLINK;
1966                                 } else if ((__le16_to_cpu(fdiro->inode.mode)
1967                                             & FILETYPE_INO_MASK) ==
1968                                            FILETYPE_INO_REG) {
1969                                         type = FILETYPE_REG;
1970                                 }
1971                         }
1972 #ifdef DEBUG
1973                         printf("iterate >%s<\n", filename);
1974 #endif /* of DEBUG */
1975                         if ((name != NULL) && (fnode != NULL)
1976                             && (ftype != NULL)) {
1977                                 if (strcmp(filename, name) == 0) {
1978                                         *ftype = type;
1979                                         *fnode = fdiro;
1980                                         return 1;
1981                                 }
1982                         } else {
1983                                 if (fdiro->inode_read == 0) {
1984                                         status = ext4fs_read_inode(diro->data,
1985                                                                  __le32_to_cpu(
1986                                                                  dirent.inode),
1987                                                                  &fdiro->inode);
1988                                         if (status == 0) {
1989                                                 free(fdiro);
1990                                                 return 0;
1991                                         }
1992                                         fdiro->inode_read = 1;
1993                                 }
1994                                 switch (type) {
1995                                 case FILETYPE_DIRECTORY:
1996                                         printf("<DIR> ");
1997                                         break;
1998                                 case FILETYPE_SYMLINK:
1999                                         printf("<SYM> ");
2000                                         break;
2001                                 case FILETYPE_REG:
2002                                         printf("      ");
2003                                         break;
2004                                 default:
2005                                         printf("< ? > ");
2006                                         break;
2007                                 }
2008                                 printf("%10d %s\n",
2009                                         __le32_to_cpu(fdiro->inode.size),
2010                                         filename);
2011                         }
2012                         free(fdiro);
2013                 }
2014                 fpos += __le16_to_cpu(dirent.direntlen);
2015         }
2016         return 0;
2017 }
2018
2019 static char *ext4fs_read_symlink(struct ext2fs_node *node)
2020 {
2021         char *symlink;
2022         struct ext2fs_node *diro = node;
2023         int status;
2024
2025         if (!diro->inode_read) {
2026                 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode);
2027                 if (status == 0)
2028                         return 0;
2029         }
2030         symlink = zalloc(__le32_to_cpu(diro->inode.size) + 1);
2031         if (!symlink)
2032                 return 0;
2033
2034         if (__le32_to_cpu(diro->inode.size) <= 60) {
2035                 strncpy(symlink, diro->inode.b.symlink,
2036                          __le32_to_cpu(diro->inode.size));
2037         } else {
2038                 status = ext4fs_read_file(diro, 0,
2039                                            __le32_to_cpu(diro->inode.size),
2040                                            symlink);
2041                 if (status == 0) {
2042                         free(symlink);
2043                         return 0;
2044                 }
2045         }
2046         symlink[__le32_to_cpu(diro->inode.size)] = '\0';
2047         return symlink;
2048 }
2049
2050 static int ext4fs_find_file1(const char *currpath,
2051                              struct ext2fs_node *currroot,
2052                              struct ext2fs_node **currfound, int *foundtype)
2053 {
2054         char fpath[strlen(currpath) + 1];
2055         char *name = fpath;
2056         char *next;
2057         int status;
2058         int type = FILETYPE_DIRECTORY;
2059         struct ext2fs_node *currnode = currroot;
2060         struct ext2fs_node *oldnode = currroot;
2061
2062         strncpy(fpath, currpath, strlen(currpath) + 1);
2063
2064         /* Remove all leading slashes. */
2065         while (*name == '/')
2066                 name++;
2067
2068         if (!*name) {
2069                 *currfound = currnode;
2070                 return 1;
2071         }
2072
2073         for (;;) {
2074                 int found;
2075
2076                 /* Extract the actual part from the pathname. */
2077                 next = strchr(name, '/');
2078                 if (next) {
2079                         /* Remove all leading slashes. */
2080                         while (*next == '/')
2081                                 *(next++) = '\0';
2082                 }
2083
2084                 if (type != FILETYPE_DIRECTORY) {
2085                         ext4fs_free_node(currnode, currroot);
2086                         return 0;
2087                 }
2088
2089                 oldnode = currnode;
2090
2091                 /* Iterate over the directory. */
2092                 found = ext4fs_iterate_dir(currnode, name, &currnode, &type);
2093                 if (found == 0)
2094                         return 0;
2095
2096                 if (found == -1)
2097                         break;
2098
2099                 /* Read in the symlink and follow it. */
2100                 if (type == FILETYPE_SYMLINK) {
2101                         char *symlink;
2102
2103                         /* Test if the symlink does not loop. */
2104                         if (++symlinknest == 8) {
2105                                 ext4fs_free_node(currnode, currroot);
2106                                 ext4fs_free_node(oldnode, currroot);
2107                                 return 0;
2108                         }
2109
2110                         symlink = ext4fs_read_symlink(currnode);
2111                         ext4fs_free_node(currnode, currroot);
2112
2113                         if (!symlink) {
2114                                 ext4fs_free_node(oldnode, currroot);
2115                                 return 0;
2116                         }
2117
2118                         debug("Got symlink >%s<\n", symlink);
2119
2120                         if (symlink[0] == '/') {
2121                                 ext4fs_free_node(oldnode, currroot);
2122                                 oldnode = &ext4fs_root->diropen;
2123                         }
2124
2125                         /* Lookup the node the symlink points to. */
2126                         status = ext4fs_find_file1(symlink, oldnode,
2127                                                     &currnode, &type);
2128
2129                         free(symlink);
2130
2131                         if (status == 0) {
2132                                 ext4fs_free_node(oldnode, currroot);
2133                                 return 0;
2134                         }
2135                 }
2136
2137                 ext4fs_free_node(oldnode, currroot);
2138
2139                 /* Found the node! */
2140                 if (!next || *next == '\0') {
2141                         *currfound = currnode;
2142                         *foundtype = type;
2143                         return 1;
2144                 }
2145                 name = next;
2146         }
2147         return -1;
2148 }
2149
2150 int ext4fs_find_file(const char *path, struct ext2fs_node *rootnode,
2151         struct ext2fs_node **foundnode, int expecttype)
2152 {
2153         int status;
2154         int foundtype = FILETYPE_DIRECTORY;
2155
2156         symlinknest = 0;
2157         if (!path)
2158                 return 0;
2159
2160         status = ext4fs_find_file1(path, rootnode, foundnode, &foundtype);
2161         if (status == 0)
2162                 return 0;
2163
2164         /* Check if the node that was found was of the expected type. */
2165         if ((expecttype == FILETYPE_REG) && (foundtype != expecttype))
2166                 return 0;
2167         else if ((expecttype == FILETYPE_DIRECTORY)
2168                    && (foundtype != expecttype))
2169                 return 0;
2170
2171         return 1;
2172 }
2173
2174 int ext4fs_open(const char *filename)
2175 {
2176         struct ext2fs_node *fdiro = NULL;
2177         int status;
2178         int len;
2179
2180         if (ext4fs_root == NULL)
2181                 return -1;
2182
2183         ext4fs_file = NULL;
2184         status = ext4fs_find_file(filename, &ext4fs_root->diropen, &fdiro,
2185                                   FILETYPE_REG);
2186         if (status == 0)
2187                 goto fail;
2188
2189         if (!fdiro->inode_read) {
2190                 status = ext4fs_read_inode(fdiro->data, fdiro->ino,
2191                                 &fdiro->inode);
2192                 if (status == 0)
2193                         goto fail;
2194         }
2195         len = __le32_to_cpu(fdiro->inode.size);
2196         ext4fs_file = fdiro;
2197
2198         return len;
2199 fail:
2200         ext4fs_free_node(fdiro, &ext4fs_root->diropen);
2201
2202         return -1;
2203 }
2204
2205 int ext4fs_mount(unsigned part_length)
2206 {
2207         struct ext2_data *data;
2208         int status;
2209         struct ext_filesystem *fs = get_fs();
2210         data = zalloc(SUPERBLOCK_SIZE);
2211         if (!data)
2212                 return 0;
2213
2214         /* Read the superblock. */
2215         status = ext4_read_superblock((char *)&data->sblock);
2216
2217         if (status == 0)
2218                 goto fail;
2219
2220         /* Make sure this is an ext2 filesystem. */
2221         if (__le16_to_cpu(data->sblock.magic) != EXT2_MAGIC)
2222                 goto fail;
2223
2224         if (__le32_to_cpu(data->sblock.revision_level == 0))
2225                 fs->inodesz = 128;
2226         else
2227                 fs->inodesz = __le16_to_cpu(data->sblock.inode_size);
2228
2229         debug("EXT2 rev %d, inode_size %d\n",
2230                __le32_to_cpu(data->sblock.revision_level), fs->inodesz);
2231
2232         data->diropen.data = data;
2233         data->diropen.ino = 2;
2234         data->diropen.inode_read = 1;
2235         data->inode = &data->diropen.inode;
2236
2237         status = ext4fs_read_inode(data, 2, data->inode);
2238         if (status == 0)
2239                 goto fail;
2240
2241         ext4fs_root = data;
2242
2243         return 1;
2244 fail:
2245         printf("Failed to mount ext2 filesystem...\n");
2246         free(data);
2247         ext4fs_root = NULL;
2248
2249         return 0;
2250 }