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 <inttypes.h>
  26 #include <malloc.h>
  27 #include <stddef.h>
  28 #include <linux/stat.h>
  29 #include <linux/time.h>
  30 #include <asm/byteorder.h>
  31 #include "ext4_common.h"
  32
  33 struct ext2_data *ext4fs_root;
  34 struct ext2fs_node *ext4fs_file;
  35 uint32_t *ext4fs_indir1_block;
  36 int ext4fs_indir1_size;
  37 int ext4fs_indir1_blkno = -1;
  38 uint32_t *ext4fs_indir2_block;
  39 int ext4fs_indir2_size;
  40 int ext4fs_indir2_blkno = -1;
  41
  42 uint32_t *ext4fs_indir3_block;
  43 int ext4fs_indir3_size;
  44 int ext4fs_indir3_blkno = -1;
  45 struct ext2_inode *g_parent_inode;
  46 static int symlinknest;
  47
  48 #if defined(CONFIG_EXT4_WRITE)
  49 uint32_t ext4fs_div_roundup(uint32_t size, uint32_t n)
  50 {
  51         uint32_t res = size / n;
  52         if (res * n != size)
  53                 res++;
  54
  55         return res;
  56 }
  57
  58 void put_ext4(uint64_t off, void *buf, uint32_t size)
  59 {
  60         uint64_t startblock;
  61         uint64_t remainder;
  62         unsigned char *temp_ptr = NULL;
  63         struct ext_filesystem *fs = get_fs();
  64         int log2blksz = fs->dev_desc->log2blksz;
  65         ALLOC_CACHE_ALIGN_BUFFER(unsigned char, sec_buf, fs->dev_desc->blksz);
  66
  67         startblock = off >> log2blksz;
  68         startblock += part_offset;
  69         remainder = off & (uint64_t)(fs->dev_desc->blksz - 1);
  70
  71         if (fs->dev_desc == NULL)
  72                 return;
  73
  74         if ((startblock + (size >> log2blksz)) >
  75             (part_offset + fs->total_sect)) {
  76                 printf("part_offset is " LBAFU "\n", part_offset);
  77                 printf("total_sector is %" PRIu64 "\n", fs->total_sect);
  78                 printf("error: overflow occurs\n");
  79                 return;
  80         }
  81
  82         if (remainder) {
  83                 if (fs->dev_desc->block_read) {
  84                         fs->dev_desc->block_read(fs->dev_desc->dev,
  85                                                  startblock, 1, sec_buf);
  86                         temp_ptr = sec_buf;
  87                         memcpy((temp_ptr + remainder),
  88                                (unsigned char *)buf, size);
  89                         fs->dev_desc->block_write(fs->dev_desc->dev,
  90                                                   startblock, 1, sec_buf);
  91                 }
  92         } else {
  93                 if (size >> log2blksz != 0) {
  94                         fs->dev_desc->block_write(fs->dev_desc->dev,
  95                                                   startblock,
  96                                                   size >> log2blksz,
  97                                                   (unsigned long *)buf);
  98                 } else {
  99                         fs->dev_desc->block_read(fs->dev_desc->dev,
 100                                                  startblock, 1, sec_buf);
 101                         temp_ptr = sec_buf;
 102                         memcpy(temp_ptr, buf, size);
 103                         fs->dev_desc->block_write(fs->dev_desc->dev,
 104                                                   startblock, 1,
 105                                                   (unsigned long *)sec_buf);
 106                 }
 107         }
 108 }
 109
 110 static int _get_new_inode_no(unsigned char *buffer)
 111 {
 112         struct ext_filesystem *fs = get_fs();
 113         unsigned char input;
 114         int operand, status;
 115         int count = 1;
 116         int j = 0;
 117
 118         /* get the blocksize of the filesystem */
 119         unsigned char *ptr = buffer;
 120         while (*ptr == 255) {
 121                 ptr++;
 122                 count += 8;
 123                 if (count > ext4fs_root->sblock.inodes_per_group)
 124                         return -1;
 125         }
 126
 127         for (j = 0; j < fs->blksz; j++) {
 128                 input = *ptr;
 129                 int i = 0;
 130                 while (i <= 7) {
 131                         operand = 1 << i;
 132                         status = input & operand;
 133                         if (status) {
 134                                 i++;
 135                                 count++;
 136                         } else {
 137                                 *ptr |= operand;
 138                                 return count;
 139                         }
 140                 }
 141                 ptr = ptr + 1;
 142         }
 143
 144         return -1;
 145 }
 146
 147 static int _get_new_blk_no(unsigned char *buffer)
 148 {
 149         unsigned char input;
 150         int operand, status;
 151         int count = 0;
 152         int j = 0;
 153         unsigned char *ptr = buffer;
 154         struct ext_filesystem *fs = get_fs();
 155
 156         if (fs->blksz != 1024)
 157                 count = 0;
 158         else
 159                 count = 1;
 160
 161         while (*ptr == 255) {
 162                 ptr++;
 163                 count += 8;
 164                 if (count == (fs->blksz * 8))
 165                         return -1;
 166         }
 167
 168         for (j = 0; j < fs->blksz; j++) {
 169                 input = *ptr;
 170                 int i = 0;
 171                 while (i <= 7) {
 172                         operand = 1 << i;
 173                         status = input & operand;
 174                         if (status) {
 175                                 i++;
 176                                 count++;
 177                         } else {
 178                                 *ptr |= operand;
 179                                 return count;
 180                         }
 181                 }
 182                 ptr = ptr + 1;
 183         }
 184
 185         return -1;
 186 }
 187
 188 int ext4fs_set_block_bmap(long int blockno, unsigned char *buffer, int index)
 189 {
 190         int i, remainder, status;
 191         unsigned char *ptr = buffer;
 192         unsigned char operand;
 193         i = blockno / 8;
 194         remainder = blockno % 8;
 195         int blocksize = EXT2_BLOCK_SIZE(ext4fs_root);
 196
 197         i = i - (index * blocksize);
 198         if (blocksize != 1024) {
 199                 ptr = ptr + i;
 200                 operand = 1 << remainder;
 201                 status = *ptr & operand;
 202                 if (status)
 203                         return -1;
 204
 205                 *ptr = *ptr | operand;
 206                 return 0;
 207         } else {
 208                 if (remainder == 0) {
 209                         ptr = ptr + i - 1;
 210                         operand = (1 << 7);
 211                 } else {
 212                         ptr = ptr + i;
 213                         operand = (1 << (remainder - 1));
 214                 }
 215                 status = *ptr & operand;
 216                 if (status)
 217                         return -1;
 218
 219                 *ptr = *ptr | operand;
 220                 return 0;
 221         }
 222 }
 223
 224 void ext4fs_reset_block_bmap(long int blockno, unsigned char *buffer, int index)
 225 {
 226         int i, remainder, status;
 227         unsigned char *ptr = buffer;
 228         unsigned char operand;
 229         i = blockno / 8;
 230         remainder = blockno % 8;
 231         int blocksize = EXT2_BLOCK_SIZE(ext4fs_root);
 232
 233         i = i - (index * blocksize);
 234         if (blocksize != 1024) {
 235                 ptr = ptr + i;
 236                 operand = (1 << remainder);
 237                 status = *ptr & operand;
 238                 if (status)
 239                         *ptr = *ptr & ~(operand);
 240         } else {
 241                 if (remainder == 0) {
 242                         ptr = ptr + i - 1;
 243                         operand = (1 << 7);
 244                 } else {
 245                         ptr = ptr + i;
 246                         operand = (1 << (remainder - 1));
 247                 }
 248                 status = *ptr & operand;
 249                 if (status)
 250                         *ptr = *ptr & ~(operand);
 251         }
 252 }
 253
 254 int ext4fs_set_inode_bmap(int inode_no, unsigned char *buffer, int index)
 255 {
 256         int i, remainder, status;
 257         unsigned char *ptr = buffer;
 258         unsigned char operand;
 259
 260         inode_no -= (index * ext4fs_root->sblock.inodes_per_group);
 261         i = inode_no / 8;
 262         remainder = inode_no % 8;
 263         if (remainder == 0) {
 264                 ptr = ptr + i - 1;
 265                 operand = (1 << 7);
 266         } else {
 267                 ptr = ptr + i;
 268                 operand = (1 << (remainder - 1));
 269         }
 270         status = *ptr & operand;
 271         if (status)
 272                 return -1;
 273
 274         *ptr = *ptr | operand;
 275
 276         return 0;
 277 }
 278
 279 void ext4fs_reset_inode_bmap(int inode_no, unsigned char *buffer, int index)
 280 {
 281         int i, remainder, status;
 282         unsigned char *ptr = buffer;
 283         unsigned char operand;
 284
 285         inode_no -= (index * ext4fs_root->sblock.inodes_per_group);
 286         i = inode_no / 8;
 287         remainder = inode_no % 8;
 288         if (remainder == 0) {
 289                 ptr = ptr + i - 1;
 290                 operand = (1 << 7);
 291         } else {
 292                 ptr = ptr + i;
 293                 operand = (1 << (remainder - 1));
 294         }
 295         status = *ptr & operand;
 296         if (status)
 297                 *ptr = *ptr & ~(operand);
 298 }
 299
 300 int ext4fs_checksum_update(unsigned int i)
 301 {
 302         struct ext2_block_group *desc;
 303         struct ext_filesystem *fs = get_fs();
 304         __u16 crc = 0;
 305
 306         desc = (struct ext2_block_group *)&fs->bgd[i];
 307         if (fs->sb->feature_ro_compat & EXT4_FEATURE_RO_COMPAT_GDT_CSUM) {
 308                 int offset = offsetof(struct ext2_block_group, bg_checksum);
 309
 310                 crc = ext2fs_crc16(~0, fs->sb->unique_id,
 311                                    sizeof(fs->sb->unique_id));
 312                 crc = ext2fs_crc16(crc, &i, sizeof(i));
 313                 crc = ext2fs_crc16(crc, desc, offset);
 314                 offset += sizeof(desc->bg_checksum);    /* skip checksum */
 315                 assert(offset == sizeof(*desc));
 316         }
 317
 318         return crc;
 319 }
 320
 321 static int check_void_in_dentry(struct ext2_dirent *dir, char *filename)
 322 {
 323         int dentry_length;
 324         int sizeof_void_space;
 325         int new_entry_byte_reqd;
 326         short padding_factor = 0;
 327
 328         if (dir->namelen % 4 != 0)
 329                 padding_factor = 4 - (dir->namelen % 4);
 330
 331         dentry_length = sizeof(struct ext2_dirent) +
 332                         dir->namelen + padding_factor;
 333         sizeof_void_space = dir->direntlen - dentry_length;
 334         if (sizeof_void_space == 0)
 335                 return 0;
 336
 337         padding_factor = 0;
 338         if (strlen(filename) % 4 != 0)
 339                 padding_factor = 4 - (strlen(filename) % 4);
 340
 341         new_entry_byte_reqd = strlen(filename) +
 342             sizeof(struct ext2_dirent) + padding_factor;
 343         if (sizeof_void_space >= new_entry_byte_reqd) {
 344                 dir->direntlen = dentry_length;
 345                 return sizeof_void_space;
 346         }
 347
 348         return 0;
 349 }
 350
 351 void ext4fs_update_parent_dentry(char *filename, int *p_ino, int file_type)
 352 {
 353         unsigned int *zero_buffer = NULL;
 354         char *root_first_block_buffer = NULL;
 355         int direct_blk_idx;
 356         long int root_blknr;
 357         long int first_block_no_of_root = 0;
 358         long int previous_blknr = -1;
 359         int totalbytes = 0;
 360         short int padding_factor = 0;
 361         unsigned int new_entry_byte_reqd;
 362         unsigned int last_entry_dirlen;
 363         int sizeof_void_space = 0;
 364         int templength = 0;
 365         int inodeno;
 366         int status;
 367         struct ext_filesystem *fs = get_fs();
 368         /* directory entry */
 369         struct ext2_dirent *dir;
 370         char *temp_dir = NULL;
 371
 372         zero_buffer = zalloc(fs->blksz);
 373         if (!zero_buffer) {
 374                 printf("No Memory\n");
 375                 return;
 376         }
 377         root_first_block_buffer = zalloc(fs->blksz);
 378         if (!root_first_block_buffer) {
 379                 free(zero_buffer);
 380                 printf("No Memory\n");
 381                 return;
 382         }
 383 restart:
 384
 385         /* read the block no allocated to a file */
 386         for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS;
 387              direct_blk_idx++) {
 388                 root_blknr = read_allocated_block(g_parent_inode,
 389                                                   direct_blk_idx);
 390                 if (root_blknr == 0) {
 391                         first_block_no_of_root = previous_blknr;
 392                         break;
 393                 }
 394                 previous_blknr = root_blknr;
 395         }
 396
 397         status = ext4fs_devread((lbaint_t)first_block_no_of_root
 398                                 * fs->sect_perblk,
 399                                 0, fs->blksz, root_first_block_buffer);
 400         if (status == 0)
 401                 goto fail;
 402
 403         if (ext4fs_log_journal(root_first_block_buffer, first_block_no_of_root))
 404                 goto fail;
 405         dir = (struct ext2_dirent *)root_first_block_buffer;
 406         totalbytes = 0;
 407         while (dir->direntlen > 0) {
 408                 /*
 409                  * blocksize-totalbytes because last directory length
 410                  * i.e. dir->direntlen is free availble space in the
 411                  * block that means  it is a last entry of directory
 412                  * entry
 413                  */
 414
 415                 /* traversing the each directory entry */
 416                 if (fs->blksz - totalbytes == dir->direntlen) {
 417                         if (strlen(filename) % 4 != 0)
 418                                 padding_factor = 4 - (strlen(filename) % 4);
 419
 420                         new_entry_byte_reqd = strlen(filename) +
 421                             sizeof(struct ext2_dirent) + padding_factor;
 422                         padding_factor = 0;
 423                         /*
 424                          * update last directory entry length to its
 425                          * length because we are creating new directory
 426                          * entry
 427                          */
 428                         if (dir->namelen % 4 != 0)
 429                                 padding_factor = 4 - (dir->namelen % 4);
 430
 431                         last_entry_dirlen = dir->namelen +
 432                             sizeof(struct ext2_dirent) + padding_factor;
 433                         if ((fs->blksz - totalbytes - last_entry_dirlen) <
 434                                 new_entry_byte_reqd) {
 435                                 printf("1st Block Full:Allocate new block\n");
 436
 437                                 if (direct_blk_idx == INDIRECT_BLOCKS - 1) {
 438                                         printf("Directory exceeds limit\n");
 439                                         goto fail;
 440                                 }
 441                                 g_parent_inode->b.blocks.dir_blocks
 442                                     [direct_blk_idx] = ext4fs_get_new_blk_no();
 443                                 if (g_parent_inode->b.blocks.dir_blocks
 444                                         [direct_blk_idx] == -1) {
 445                                         printf("no block left to assign\n");
 446                                         goto fail;
 447                                 }
 448                                 put_ext4(((uint64_t)
 449                                           ((uint64_t)g_parent_inode->b.
 450                                            blocks.dir_blocks[direct_blk_idx] *
 451                                            (uint64_t)fs->blksz)), zero_buffer, fs->blksz);
 452                                 g_parent_inode->size =
 453                                     g_parent_inode->size + fs->blksz;
 454                                 g_parent_inode->blockcnt =
 455                                     g_parent_inode->blockcnt + fs->sect_perblk;
 456                                 if (ext4fs_put_metadata
 457                                     (root_first_block_buffer,
 458                                      first_block_no_of_root))
 459                                         goto fail;
 460                                 goto restart;
 461                         }
 462                         dir->direntlen = last_entry_dirlen;
 463                         break;
 464                 }
 465
 466                 templength = dir->direntlen;
 467                 totalbytes = totalbytes + templength;
 468                 sizeof_void_space = check_void_in_dentry(dir, filename);
 469                 if (sizeof_void_space)
 470                         break;
 471
 472                 dir = (struct ext2_dirent *)((char *)dir + templength);
 473         }
 474
 475         /* make a pointer ready for creating next directory entry */
 476         templength = dir->direntlen;
 477         totalbytes = totalbytes + templength;
 478         dir = (struct ext2_dirent *)((char *)dir + templength);
 479
 480         /* get the next available inode number */
 481         inodeno = ext4fs_get_new_inode_no();
 482         if (inodeno == -1) {
 483                 printf("no inode left to assign\n");
 484                 goto fail;
 485         }
 486         dir->inode = inodeno;
 487         if (sizeof_void_space)
 488                 dir->direntlen = sizeof_void_space;
 489         else
 490                 dir->direntlen = fs->blksz - totalbytes;
 491
 492         dir->namelen = strlen(filename);
 493         dir->filetype = FILETYPE_REG;   /* regular file */
 494         temp_dir = (char *)dir;
 495         temp_dir = temp_dir + sizeof(struct ext2_dirent);
 496         memcpy(temp_dir, filename, strlen(filename));
 497
 498         *p_ino = inodeno;
 499
 500         /* update or write  the 1st block of root inode */
 501         if (ext4fs_put_metadata(root_first_block_buffer,
 502                                 first_block_no_of_root))
 503                 goto fail;
 504
 505 fail:
 506         free(zero_buffer);
 507         free(root_first_block_buffer);
 508 }
 509
 510 static int search_dir(struct ext2_inode *parent_inode, char *dirname)
 511 {
 512         int status;
 513         int inodeno;
 514         int totalbytes;
 515         int templength;
 516         int direct_blk_idx;
 517         long int blknr;
 518         int found = 0;
 519         char *ptr = NULL;
 520         unsigned char *block_buffer = NULL;
 521         struct ext2_dirent *dir = NULL;
 522         struct ext2_dirent *previous_dir = NULL;
 523         struct ext_filesystem *fs = get_fs();
 524
 525         /* read the block no allocated to a file */
 526         for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS;
 527                 direct_blk_idx++) {
 528                 blknr = read_allocated_block(parent_inode, direct_blk_idx);
 529                 if (blknr == 0)
 530                         goto fail;
 531
 532                 /* read the blocks of parenet inode */
 533                 block_buffer = zalloc(fs->blksz);
 534                 if (!block_buffer)
 535                         goto fail;
 536
 537                 status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk,
 538                                         0, fs->blksz, (char *)block_buffer);
 539                 if (status == 0)
 540                         goto fail;
 541
 542                 dir = (struct ext2_dirent *)block_buffer;
 543                 ptr = (char *)dir;
 544                 totalbytes = 0;
 545                 while (dir->direntlen >= 0) {
 546                         /*
 547                          * blocksize-totalbytes because last directory
 548                          * length i.e.,*dir->direntlen is free availble
 549                          * space in the block that means
 550                          * it is a last entry of directory entry
 551                          */
 552                         if (strlen(dirname) == dir->namelen) {
 553                                 if (strncmp(dirname, ptr +
 554                                         sizeof(struct ext2_dirent),
 555                                         dir->namelen) == 0) {
 556                                         previous_dir->direntlen +=
 557                                                         dir->direntlen;
 558                                         inodeno = dir->inode;
 559                                         dir->inode = 0;
 560                                         found = 1;
 561                                         break;
 562                                 }
 563                         }
 564
 565                         if (fs->blksz - totalbytes == dir->direntlen)
 566                                 break;
 567
 568                         /* traversing the each directory entry */
 569                         templength = dir->direntlen;
 570                         totalbytes = totalbytes + templength;
 571                         previous_dir = dir;
 572                         dir = (struct ext2_dirent *)((char *)dir + templength);
 573                         ptr = (char *)dir;
 574                 }
 575
 576                 if (found == 1) {
 577                         free(block_buffer);
 578                         block_buffer = NULL;
 579                         return inodeno;
 580                 }
 581
 582                 free(block_buffer);
 583                 block_buffer = NULL;
 584         }
 585
 586 fail:
 587         free(block_buffer);
 588
 589         return -1;
 590 }
 591
 592 static int find_dir_depth(char *dirname)
 593 {
 594         char *token = strtok(dirname, "/");
 595         int count = 0;
 596         while (token != NULL) {
 597                 token = strtok(NULL, "/");
 598                 count++;
 599         }
 600         return count + 1 + 1;
 601         /*
 602          * for example  for string /home/temp
 603          * depth=home(1)+temp(1)+1 extra for NULL;
 604          * so count is 4;
 605          */
 606 }
 607
 608 static int parse_path(char **arr, char *dirname)
 609 {
 610         char *token = strtok(dirname, "/");
 611         int i = 0;
 612
 613         /* add root */
 614         arr[i] = zalloc(strlen("/") + 1);
 615         if (!arr[i])
 616                 return -ENOMEM;
 617
 618         arr[i++] = "/";
 619
 620         /* add each path entry after root */
 621         while (token != NULL) {
 622                 arr[i] = zalloc(strlen(token) + 1);
 623                 if (!arr[i])
 624                         return -ENOMEM;
 625                 memcpy(arr[i++], token, strlen(token));
 626                 token = strtok(NULL, "/");
 627         }
 628         arr[i] = NULL;
 629
 630         return 0;
 631 }
 632
 633 int ext4fs_iget(int inode_no, struct ext2_inode *inode)
 634 {
 635         if (ext4fs_read_inode(ext4fs_root, inode_no, inode) == 0)
 636                 return -1;
 637
 638         return 0;
 639 }
 640
 641 /*
 642  * Function: ext4fs_get_parent_inode_num
 643  * Return Value: inode Number of the parent directory of  file/Directory to be
 644  * created
 645  * dirname : Input parmater, input path name of the file/directory to be created
 646  * dname : Output parameter, to be filled with the name of the directory
 647  * extracted from dirname
 648  */
 649 int ext4fs_get_parent_inode_num(const char *dirname, char *dname, int flags)
 650 {
 651         int i;
 652         int depth = 0;
 653         int matched_inode_no;
 654         int result_inode_no = -1;
 655         char **ptr = NULL;
 656         char *depth_dirname = NULL;
 657         char *parse_dirname = NULL;
 658         struct ext2_inode *parent_inode = NULL;
 659         struct ext2_inode *first_inode = NULL;
 660         struct ext2_inode temp_inode;
 661
 662         if (*dirname != '/') {
 663                 printf("Please supply Absolute path\n");
 664                 return -1;
 665         }
 666
 667         /* TODO: input validation make equivalent to linux */
 668         depth_dirname = zalloc(strlen(dirname) + 1);
 669         if (!depth_dirname)
 670                 return -ENOMEM;
 671
 672         memcpy(depth_dirname, dirname, strlen(dirname));
 673         depth = find_dir_depth(depth_dirname);
 674         parse_dirname = zalloc(strlen(dirname) + 1);
 675         if (!parse_dirname)
 676                 goto fail;
 677         memcpy(parse_dirname, dirname, strlen(dirname));
 678
 679         /* allocate memory for each directory level */
 680         ptr = zalloc((depth) * sizeof(char *));
 681         if (!ptr)
 682                 goto fail;
 683         if (parse_path(ptr, parse_dirname))
 684                 goto fail;
 685         parent_inode = zalloc(sizeof(struct ext2_inode));
 686         if (!parent_inode)
 687                 goto fail;
 688         first_inode = zalloc(sizeof(struct ext2_inode));
 689         if (!first_inode)
 690                 goto fail;
 691         memcpy(parent_inode, ext4fs_root->inode, sizeof(struct ext2_inode));
 692         memcpy(first_inode, parent_inode, sizeof(struct ext2_inode));
 693         if (flags & F_FILE)
 694                 result_inode_no = EXT2_ROOT_INO;
 695         for (i = 1; i < depth; i++) {
 696                 matched_inode_no = search_dir(parent_inode, ptr[i]);
 697                 if (matched_inode_no == -1) {
 698                         if (ptr[i + 1] == NULL && i == 1) {
 699                                 result_inode_no = EXT2_ROOT_INO;
 700                                 goto end;
 701                         } else {
 702                                 if (ptr[i + 1] == NULL)
 703                                         break;
 704                                 printf("Invalid path\n");
 705                                 result_inode_no = -1;
 706                                 goto fail;
 707                         }
 708                 } else {
 709                         if (ptr[i + 1] != NULL) {
 710                                 memset(parent_inode, '\0',
 711                                        sizeof(struct ext2_inode));
 712                                 if (ext4fs_iget(matched_inode_no,
 713                                                 parent_inode)) {
 714                                         result_inode_no = -1;
 715                                         goto fail;
 716                                 }
 717                                 result_inode_no = matched_inode_no;
 718                         } else {
 719                                 break;
 720                         }
 721                 }
 722         }
 723
 724 end:
 725         if (i == 1)
 726                 matched_inode_no = search_dir(first_inode, ptr[i]);
 727         else
 728                 matched_inode_no = search_dir(parent_inode, ptr[i]);
 729
 730         if (matched_inode_no != -1) {
 731                 ext4fs_iget(matched_inode_no, &temp_inode);
 732                 if (temp_inode.mode & S_IFDIR) {
 733                         printf("It is a Directory\n");
 734                         result_inode_no = -1;
 735                         goto fail;
 736                 }
 737         }
 738
 739         if (strlen(ptr[i]) > 256) {
 740                 result_inode_no = -1;
 741                 goto fail;
 742         }
 743         memcpy(dname, ptr[i], strlen(ptr[i]));
 744
 745 fail:
 746         free(depth_dirname);
 747         free(parse_dirname);
 748         free(ptr);
 749         free(parent_inode);
 750         free(first_inode);
 751
 752         return result_inode_no;
 753 }
 754
 755 static int check_filename(char *filename, unsigned int blknr)
 756 {
 757         unsigned int first_block_no_of_root;
 758         int totalbytes = 0;
 759         int templength = 0;
 760         int status, inodeno;
 761         int found = 0;
 762         char *root_first_block_buffer = NULL;
 763         char *root_first_block_addr = NULL;
 764         struct ext2_dirent *dir = NULL;
 765         struct ext2_dirent *previous_dir = NULL;
 766         char *ptr = NULL;
 767         struct ext_filesystem *fs = get_fs();
 768
 769         /* get the first block of root */
 770         first_block_no_of_root = blknr;
 771         root_first_block_buffer = zalloc(fs->blksz);
 772         if (!root_first_block_buffer)
 773                 return -ENOMEM;
 774         root_first_block_addr = root_first_block_buffer;
 775         status = ext4fs_devread((lbaint_t)first_block_no_of_root *
 776                                 fs->sect_perblk, 0,
 777                                 fs->blksz, root_first_block_buffer);
 778         if (status == 0)
 779                 goto fail;
 780
 781         if (ext4fs_log_journal(root_first_block_buffer, first_block_no_of_root))
 782                 goto fail;
 783         dir = (struct ext2_dirent *)root_first_block_buffer;
 784         ptr = (char *)dir;
 785         totalbytes = 0;
 786         while (dir->direntlen >= 0) {
 787                 /*
 788                  * blocksize-totalbytes because last
 789                  * directory length i.e., *dir->direntlen
 790                  * is free availble space in the block that
 791                  * means it is a last entry of directory entry
 792                  */
 793                 if (strlen(filename) == dir->namelen) {
 794                         if (strncmp(filename, ptr + sizeof(struct ext2_dirent),
 795                                 dir->namelen) == 0) {
 796                                 printf("file found deleting\n");
 797                                 previous_dir->direntlen += dir->direntlen;
 798                                 inodeno = dir->inode;
 799                                 dir->inode = 0;
 800                                 found = 1;
 801                                 break;
 802                         }
 803                 }
 804
 805                 if (fs->blksz - totalbytes == dir->direntlen)
 806                         break;
 807
 808                 /* traversing the each directory entry */
 809                 templength = dir->direntlen;
 810                 totalbytes = totalbytes + templength;
 811                 previous_dir = dir;
 812                 dir = (struct ext2_dirent *)((char *)dir + templength);
 813                 ptr = (char *)dir;
 814         }
 815
 816
 817         if (found == 1) {
 818                 if (ext4fs_put_metadata(root_first_block_addr,
 819                                         first_block_no_of_root))
 820                         goto fail;
 821                 return inodeno;
 822         }
 823 fail:
 824         free(root_first_block_buffer);
 825
 826         return -1;
 827 }
 828
 829 int ext4fs_filename_check(char *filename)
 830 {
 831         short direct_blk_idx = 0;
 832         long int blknr = -1;
 833         int inodeno = -1;
 834
 835         /* read the block no allocated to a file */
 836         for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS;
 837                 direct_blk_idx++) {
 838                 blknr = read_allocated_block(g_parent_inode, direct_blk_idx);
 839                 if (blknr == 0)
 840                         break;
 841                 inodeno = check_filename(filename, blknr);
 842                 if (inodeno != -1)
 843                         return inodeno;
 844         }
 845
 846         return -1;
 847 }
 848
 849 long int ext4fs_get_new_blk_no(void)
 850 {
 851         short i;
 852         short status;
 853         int remainder;
 854         unsigned int bg_idx;
 855         static int prev_bg_bitmap_index = -1;
 856         unsigned int blk_per_grp = ext4fs_root->sblock.blocks_per_group;
 857         struct ext_filesystem *fs = get_fs();
 858         char *journal_buffer = zalloc(fs->blksz);
 859         char *zero_buffer = zalloc(fs->blksz);
 860         if (!journal_buffer || !zero_buffer)
 861                 goto fail;
 862         struct ext2_block_group *bgd = (struct ext2_block_group *)fs->gdtable;
 863
 864         if (fs->first_pass_bbmap == 0) {
 865                 for (i = 0; i < fs->no_blkgrp; i++) {
 866                         if (bgd[i].free_blocks) {
 867                                 if (bgd[i].bg_flags & EXT4_BG_BLOCK_UNINIT) {
 868                                         put_ext4(((uint64_t) ((uint64_t)bgd[i].block_id *
 869                                                               (uint64_t)fs->blksz)),
 870                                                  zero_buffer, fs->blksz);
 871                                         bgd[i].bg_flags =
 872                                             bgd[i].
 873                                             bg_flags & ~EXT4_BG_BLOCK_UNINIT;
 874                                         memcpy(fs->blk_bmaps[i], zero_buffer,
 875                                                fs->blksz);
 876                                 }
 877                                 fs->curr_blkno =
 878                                     _get_new_blk_no(fs->blk_bmaps[i]);
 879                                 if (fs->curr_blkno == -1)
 880                                         /* if block bitmap is completely fill */
 881                                         continue;
 882                                 fs->curr_blkno = fs->curr_blkno +
 883                                                 (i * fs->blksz * 8);
 884                                 fs->first_pass_bbmap++;
 885                                 bgd[i].free_blocks--;
 886                                 fs->sb->free_blocks--;
 887                                 status = ext4fs_devread((lbaint_t)
 888                                                         bgd[i].block_id *
 889                                                         fs->sect_perblk, 0,
 890                                                         fs->blksz,
 891                                                         journal_buffer);
 892                                 if (status == 0)
 893                                         goto fail;
 894                                 if (ext4fs_log_journal(journal_buffer,
 895                                                         bgd[i].block_id))
 896                                         goto fail;
 897                                 goto success;
 898                         } else {
 899                                 debug("no space left on block group %d\n", i);
 900                         }
 901                 }
 902
 903                 goto fail;
 904         } else {
 905 restart:
 906                 fs->curr_blkno++;
 907                 /* get the blockbitmap index respective to blockno */
 908                 bg_idx = fs->curr_blkno / blk_per_grp;
 909                 if (fs->blksz == 1024) {
 910                         remainder = fs->curr_blkno % blk_per_grp;
 911                         if (!remainder)
 912                                 bg_idx--;
 913                 }
 914
 915                 /*
 916                  * To skip completely filled block group bitmaps
 917                  * Optimize the block allocation
 918                  */
 919                 if (bg_idx >= fs->no_blkgrp)
 920                         goto fail;
 921
 922                 if (bgd[bg_idx].free_blocks == 0) {
 923                         debug("block group %u is full. Skipping\n", bg_idx);
 924                         fs->curr_blkno = fs->curr_blkno + blk_per_grp;
 925                         fs->curr_blkno--;
 926                         goto restart;
 927                 }
 928
 929                 if (bgd[bg_idx].bg_flags & EXT4_BG_BLOCK_UNINIT) {
 930                         memset(zero_buffer, '\0', fs->blksz);
 931                         put_ext4(((uint64_t) ((uint64_t)bgd[bg_idx].block_id *
 932                                         (uint64_t)fs->blksz)), zero_buffer, fs->blksz);
 933                         memcpy(fs->blk_bmaps[bg_idx], zero_buffer, fs->blksz);
 934                         bgd[bg_idx].bg_flags = bgd[bg_idx].bg_flags &
 935                                                 ~EXT4_BG_BLOCK_UNINIT;
 936                 }
 937
 938                 if (ext4fs_set_block_bmap(fs->curr_blkno, fs->blk_bmaps[bg_idx],
 939                                    bg_idx) != 0) {
 940                         debug("going for restart for the block no %ld %u\n",
 941                               fs->curr_blkno, bg_idx);
 942                         goto restart;
 943                 }
 944
 945                 /* journal backup */
 946                 if (prev_bg_bitmap_index != bg_idx) {
 947                         memset(journal_buffer, '\0', fs->blksz);
 948                         status = ext4fs_devread((lbaint_t)bgd[bg_idx].block_id
 949                                                 * fs->sect_perblk,
 950                                                 0, fs->blksz, journal_buffer);
 951                         if (status == 0)
 952                                 goto fail;
 953                         if (ext4fs_log_journal(journal_buffer,
 954                                                 bgd[bg_idx].block_id))
 955                                 goto fail;
 956
 957                         prev_bg_bitmap_index = bg_idx;
 958                 }
 959                 bgd[bg_idx].free_blocks--;
 960                 fs->sb->free_blocks--;
 961                 goto success;
 962         }
 963 success:
 964         free(journal_buffer);
 965         free(zero_buffer);
 966
 967         return fs->curr_blkno;
 968 fail:
 969         free(journal_buffer);
 970         free(zero_buffer);
 971
 972         return -1;
 973 }
 974
 975 int ext4fs_get_new_inode_no(void)
 976 {
 977         short i;
 978         short status;
 979         unsigned int ibmap_idx;
 980         static int prev_inode_bitmap_index = -1;
 981         unsigned int inodes_per_grp = ext4fs_root->sblock.inodes_per_group;
 982         struct ext_filesystem *fs = get_fs();
 983         char *journal_buffer = zalloc(fs->blksz);
 984         char *zero_buffer = zalloc(fs->blksz);
 985         if (!journal_buffer || !zero_buffer)
 986                 goto fail;
 987         struct ext2_block_group *bgd = (struct ext2_block_group *)fs->gdtable;
 988
 989         if (fs->first_pass_ibmap == 0) {
 990                 for (i = 0; i < fs->no_blkgrp; i++) {
 991                         if (bgd[i].free_inodes) {
 992                                 if (bgd[i].bg_itable_unused !=
 993                                                 bgd[i].free_inodes)
 994                                         bgd[i].bg_itable_unused =
 995                                                 bgd[i].free_inodes;
 996                                 if (bgd[i].bg_flags & EXT4_BG_INODE_UNINIT) {
 997                                         put_ext4(((uint64_t)
 998                                                   ((uint64_t)bgd[i].inode_id *
 999                                                         (uint64_t)fs->blksz)),
1000                                                  zero_buffer, fs->blksz);
1001                                         bgd[i].bg_flags = bgd[i].bg_flags &
1002                                                         ~EXT4_BG_INODE_UNINIT;
1003                                         memcpy(fs->inode_bmaps[i],
1004                                                zero_buffer, fs->blksz);
1005                                 }
1006                                 fs->curr_inode_no =
1007                                     _get_new_inode_no(fs->inode_bmaps[i]);
1008                                 if (fs->curr_inode_no == -1)
1009                                         /* if block bitmap is completely fill */
1010                                         continue;
1011                                 fs->curr_inode_no = fs->curr_inode_no +
1012                                                         (i * inodes_per_grp);
1013                                 fs->first_pass_ibmap++;
1014                                 bgd[i].free_inodes--;
1015                                 bgd[i].bg_itable_unused--;
1016                                 fs->sb->free_inodes--;
1017                                 status = ext4fs_devread((lbaint_t)
1018                                                         bgd[i].inode_id *
1019                                                         fs->sect_perblk, 0,
1020                                                         fs->blksz,
1021                                                         journal_buffer);
1022                                 if (status == 0)
1023                                         goto fail;
1024                                 if (ext4fs_log_journal(journal_buffer,
1025                                                         bgd[i].inode_id))
1026                                         goto fail;
1027                                 goto success;
1028                         } else
1029                                 debug("no inode left on block group %d\n", i);
1030                 }
1031                 goto fail;
1032         } else {
1033 restart:
1034                 fs->curr_inode_no++;
1035                 /* get the blockbitmap index respective to blockno */
1036                 ibmap_idx = fs->curr_inode_no / inodes_per_grp;
1037                 if (bgd[ibmap_idx].bg_flags & EXT4_BG_INODE_UNINIT) {
1038                         memset(zero_buffer, '\0', fs->blksz);
1039                         put_ext4(((uint64_t) ((uint64_t)bgd[ibmap_idx].inode_id *
1040                                               (uint64_t)fs->blksz)), zero_buffer,
1041                                  fs->blksz);
1042                         bgd[ibmap_idx].bg_flags =
1043                             bgd[ibmap_idx].bg_flags & ~EXT4_BG_INODE_UNINIT;
1044                         memcpy(fs->inode_bmaps[ibmap_idx], zero_buffer,
1045                                 fs->blksz);
1046                 }
1047
1048                 if (ext4fs_set_inode_bmap(fs->curr_inode_no,
1049                                           fs->inode_bmaps[ibmap_idx],
1050                                           ibmap_idx) != 0) {
1051                         debug("going for restart for the block no %d %u\n",
1052                               fs->curr_inode_no, ibmap_idx);
1053                         goto restart;
1054                 }
1055
1056                 /* journal backup */
1057                 if (prev_inode_bitmap_index != ibmap_idx) {
1058                         memset(journal_buffer, '\0', fs->blksz);
1059                         status = ext4fs_devread((lbaint_t)
1060                                                 bgd[ibmap_idx].inode_id
1061                                                 * fs->sect_perblk,
1062                                                 0, fs->blksz, journal_buffer);
1063                         if (status == 0)
1064                                 goto fail;
1065                         if (ext4fs_log_journal(journal_buffer,
1066                                                 bgd[ibmap_idx].inode_id))
1067                                 goto fail;
1068                         prev_inode_bitmap_index = ibmap_idx;
1069                 }
1070                 if (bgd[ibmap_idx].bg_itable_unused !=
1071                                 bgd[ibmap_idx].free_inodes)
1072                         bgd[ibmap_idx].bg_itable_unused =
1073                                         bgd[ibmap_idx].free_inodes;
1074                 bgd[ibmap_idx].free_inodes--;
1075                 bgd[ibmap_idx].bg_itable_unused--;
1076                 fs->sb->free_inodes--;
1077                 goto success;
1078         }
1079
1080 success:
1081         free(journal_buffer);
1082         free(zero_buffer);
1083
1084         return fs->curr_inode_no;
1085 fail:
1086         free(journal_buffer);
1087         free(zero_buffer);
1088
1089         return -1;
1090
1091 }
1092
1093
1094 static void alloc_single_indirect_block(struct ext2_inode *file_inode,
1095                                         unsigned int *total_remaining_blocks,
1096                                         unsigned int *no_blks_reqd)
1097 {
1098         short i;
1099         short status;
1100         long int actual_block_no;
1101         long int si_blockno;
1102         /* si :single indirect */
1103         unsigned int *si_buffer = NULL;
1104         unsigned int *si_start_addr = NULL;
1105         struct ext_filesystem *fs = get_fs();
1106
1107         if (*total_remaining_blocks != 0) {
1108                 si_buffer = zalloc(fs->blksz);
1109                 if (!si_buffer) {
1110                         printf("No Memory\n");
1111                         return;
1112                 }
1113                 si_start_addr = si_buffer;
1114                 si_blockno = ext4fs_get_new_blk_no();
1115                 if (si_blockno == -1) {
1116                         printf("no block left to assign\n");
1117                         goto fail;
1118                 }
1119                 (*no_blks_reqd)++;
1120                 debug("SIPB %ld: %u\n", si_blockno, *total_remaining_blocks);
1121
1122                 status = ext4fs_devread((lbaint_t)si_blockno * fs->sect_perblk,
1123                                         0, fs->blksz, (char *)si_buffer);
1124                 memset(si_buffer, '\0', fs->blksz);
1125                 if (status == 0)
1126                         goto fail;
1127
1128                 for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
1129                         actual_block_no = ext4fs_get_new_blk_no();
1130                         if (actual_block_no == -1) {
1131                                 printf("no block left to assign\n");
1132                                 goto fail;
1133                         }
1134                         *si_buffer = actual_block_no;
1135                         debug("SIAB %u: %u\n", *si_buffer,
1136                                 *total_remaining_blocks);
1137
1138                         si_buffer++;
1139                         (*total_remaining_blocks)--;
1140                         if (*total_remaining_blocks == 0)
1141                                 break;
1142                 }
1143
1144                 /* write the block to disk */
1145                 put_ext4(((uint64_t) ((uint64_t)si_blockno * (uint64_t)fs->blksz)),
1146                          si_start_addr, fs->blksz);
1147                 file_inode->b.blocks.indir_block = si_blockno;
1148         }
1149 fail:
1150         free(si_start_addr);
1151 }
1152
1153 static void alloc_double_indirect_block(struct ext2_inode *file_inode,
1154                                         unsigned int *total_remaining_blocks,
1155                                         unsigned int *no_blks_reqd)
1156 {
1157         short i;
1158         short j;
1159         short status;
1160         long int actual_block_no;
1161         /* di:double indirect */
1162         long int di_blockno_parent;
1163         long int di_blockno_child;
1164         unsigned int *di_parent_buffer = NULL;
1165         unsigned int *di_child_buff = NULL;
1166         unsigned int *di_block_start_addr = NULL;
1167         unsigned int *di_child_buff_start = NULL;
1168         struct ext_filesystem *fs = get_fs();
1169
1170         if (*total_remaining_blocks != 0) {
1171                 /* double indirect parent block connecting to inode */
1172                 di_blockno_parent = ext4fs_get_new_blk_no();
1173                 if (di_blockno_parent == -1) {
1174                         printf("no block left to assign\n");
1175                         goto fail;
1176                 }
1177                 di_parent_buffer = zalloc(fs->blksz);
1178                 if (!di_parent_buffer)
1179                         goto fail;
1180
1181                 di_block_start_addr = di_parent_buffer;
1182                 (*no_blks_reqd)++;
1183                 debug("DIPB %ld: %u\n", di_blockno_parent,
1184                       *total_remaining_blocks);
1185
1186                 status = ext4fs_devread((lbaint_t)di_blockno_parent *
1187                                         fs->sect_perblk, 0,
1188                                         fs->blksz, (char *)di_parent_buffer);
1189
1190                 if (!status) {
1191                         printf("%s: Device read error!\n", __func__);
1192                         goto fail;
1193                 }
1194                 memset(di_parent_buffer, '\0', fs->blksz);
1195
1196                 /*
1197                  * start:for each double indirect parent
1198                  * block create one more block
1199                  */
1200                 for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
1201                         di_blockno_child = ext4fs_get_new_blk_no();
1202                         if (di_blockno_child == -1) {
1203                                 printf("no block left to assign\n");
1204                                 goto fail;
1205                         }
1206                         di_child_buff = zalloc(fs->blksz);
1207                         if (!di_child_buff)
1208                                 goto fail;
1209
1210                         di_child_buff_start = di_child_buff;
1211                         *di_parent_buffer = di_blockno_child;
1212                         di_parent_buffer++;
1213                         (*no_blks_reqd)++;
1214                         debug("DICB %ld: %u\n", di_blockno_child,
1215                               *total_remaining_blocks);
1216
1217                         status = ext4fs_devread((lbaint_t)di_blockno_child *
1218                                                 fs->sect_perblk, 0,
1219                                                 fs->blksz,
1220                                                 (char *)di_child_buff);
1221
1222                         if (!status) {
1223                                 printf("%s: Device read error!\n", __func__);
1224                                 goto fail;
1225                         }
1226                         memset(di_child_buff, '\0', fs->blksz);
1227                         /* filling of actual datablocks for each child */
1228                         for (j = 0; j < (fs->blksz / sizeof(int)); j++) {
1229                                 actual_block_no = ext4fs_get_new_blk_no();
1230                                 if (actual_block_no == -1) {
1231                                         printf("no block left to assign\n");
1232                                         goto fail;
1233                                 }
1234                                 *di_child_buff = actual_block_no;
1235                                 debug("DIAB %ld: %u\n", actual_block_no,
1236                                       *total_remaining_blocks);
1237
1238                                 di_child_buff++;
1239                                 (*total_remaining_blocks)--;
1240                                 if (*total_remaining_blocks == 0)
1241                                         break;
1242                         }
1243                         /* write the block  table */
1244                         put_ext4(((uint64_t) ((uint64_t)di_blockno_child * (uint64_t)fs->blksz)),
1245                                  di_child_buff_start, fs->blksz);
1246                         free(di_child_buff_start);
1247                         di_child_buff_start = NULL;
1248
1249                         if (*total_remaining_blocks == 0)
1250                                 break;
1251                 }
1252                 put_ext4(((uint64_t) ((uint64_t)di_blockno_parent * (uint64_t)fs->blksz)),
1253                          di_block_start_addr, fs->blksz);
1254                 file_inode->b.blocks.double_indir_block = di_blockno_parent;
1255         }
1256 fail:
1257         free(di_block_start_addr);
1258 }
1259
1260 static void alloc_triple_indirect_block(struct ext2_inode *file_inode,
1261                                         unsigned int *total_remaining_blocks,
1262                                         unsigned int *no_blks_reqd)
1263 {
1264         short i;
1265         short j;
1266         short k;
1267         long int actual_block_no;
1268         /* ti: Triple Indirect */
1269         long int ti_gp_blockno;
1270         long int ti_parent_blockno;
1271         long int ti_child_blockno;
1272         unsigned int *ti_gp_buff = NULL;
1273         unsigned int *ti_parent_buff = NULL;
1274         unsigned int *ti_child_buff = NULL;
1275         unsigned int *ti_gp_buff_start_addr = NULL;
1276         unsigned int *ti_pbuff_start_addr = NULL;
1277         unsigned int *ti_cbuff_start_addr = NULL;
1278         struct ext_filesystem *fs = get_fs();
1279         if (*total_remaining_blocks != 0) {
1280                 /* triple indirect grand parent block connecting to inode */
1281                 ti_gp_blockno = ext4fs_get_new_blk_no();
1282                 if (ti_gp_blockno == -1) {
1283                         printf("no block left to assign\n");
1284                         goto fail;
1285                 }
1286                 ti_gp_buff = zalloc(fs->blksz);
1287                 if (!ti_gp_buff)
1288                         goto fail;
1289
1290                 ti_gp_buff_start_addr = ti_gp_buff;
1291                 (*no_blks_reqd)++;
1292                 debug("TIGPB %ld: %u\n", ti_gp_blockno,
1293                       *total_remaining_blocks);
1294
1295                 /* for each 4 byte grand parent entry create one more block */
1296                 for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
1297                         ti_parent_blockno = ext4fs_get_new_blk_no();
1298                         if (ti_parent_blockno == -1) {
1299                                 printf("no block left to assign\n");
1300                                 goto fail;
1301                         }
1302                         ti_parent_buff = zalloc(fs->blksz);
1303                         if (!ti_parent_buff)
1304                                 goto fail;
1305
1306                         ti_pbuff_start_addr = ti_parent_buff;
1307                         *ti_gp_buff = ti_parent_blockno;
1308                         ti_gp_buff++;
1309                         (*no_blks_reqd)++;
1310                         debug("TIPB %ld: %u\n", ti_parent_blockno,
1311                               *total_remaining_blocks);
1312
1313                         /* for each 4 byte entry parent create one more block */
1314                         for (j = 0; j < (fs->blksz / sizeof(int)); j++) {
1315                                 ti_child_blockno = ext4fs_get_new_blk_no();
1316                                 if (ti_child_blockno == -1) {
1317                                         printf("no block left assign\n");
1318                                         goto fail;
1319                                 }
1320                                 ti_child_buff = zalloc(fs->blksz);
1321                                 if (!ti_child_buff)
1322                                         goto fail;
1323
1324                                 ti_cbuff_start_addr = ti_child_buff;
1325                                 *ti_parent_buff = ti_child_blockno;
1326                                 ti_parent_buff++;
1327                                 (*no_blks_reqd)++;
1328                                 debug("TICB %ld: %u\n", ti_parent_blockno,
1329                                       *total_remaining_blocks);
1330
1331                                 /* fill actual datablocks for each child */
1332                                 for (k = 0; k < (fs->blksz / sizeof(int));
1333                                         k++) {
1334                                         actual_block_no =
1335                                             ext4fs_get_new_blk_no();
1336                                         if (actual_block_no == -1) {
1337                                                 printf("no block left\n");
1338                                                 goto fail;
1339                                         }
1340                                         *ti_child_buff = actual_block_no;
1341                                         debug("TIAB %ld: %u\n", actual_block_no,
1342                                               *total_remaining_blocks);
1343
1344                                         ti_child_buff++;
1345                                         (*total_remaining_blocks)--;
1346                                         if (*total_remaining_blocks == 0)
1347                                                 break;
1348                                 }
1349                                 /* write the child block */
1350                                 put_ext4(((uint64_t) ((uint64_t)ti_child_blockno *
1351                                                       (uint64_t)fs->blksz)),
1352                                          ti_cbuff_start_addr, fs->blksz);
1353                                 free(ti_cbuff_start_addr);
1354
1355                                 if (*total_remaining_blocks == 0)
1356                                         break;
1357                         }
1358                         /* write the parent block */
1359                         put_ext4(((uint64_t) ((uint64_t)ti_parent_blockno * (uint64_t)fs->blksz)),
1360                                  ti_pbuff_start_addr, fs->blksz);
1361                         free(ti_pbuff_start_addr);
1362
1363                         if (*total_remaining_blocks == 0)
1364                                 break;
1365                 }
1366                 /* write the grand parent block */
1367                 put_ext4(((uint64_t) ((uint64_t)ti_gp_blockno * (uint64_t)fs->blksz)),
1368                          ti_gp_buff_start_addr, fs->blksz);
1369                 file_inode->b.blocks.triple_indir_block = ti_gp_blockno;
1370         }
1371 fail:
1372         free(ti_gp_buff_start_addr);
1373 }
1374
1375 void ext4fs_allocate_blocks(struct ext2_inode *file_inode,
1376                                 unsigned int total_remaining_blocks,
1377                                 unsigned int *total_no_of_block)
1378 {
1379         short i;
1380         long int direct_blockno;
1381         unsigned int no_blks_reqd = 0;
1382
1383         /* allocation of direct blocks */
1384         for (i = 0; total_remaining_blocks && i < INDIRECT_BLOCKS; i++) {
1385                 direct_blockno = ext4fs_get_new_blk_no();
1386                 if (direct_blockno == -1) {
1387                         printf("no block left to assign\n");
1388                         return;
1389                 }
1390                 file_inode->b.blocks.dir_blocks[i] = direct_blockno;
1391                 debug("DB %ld: %u\n", direct_blockno, total_remaining_blocks);
1392
1393                 total_remaining_blocks--;
1394         }
1395
1396         alloc_single_indirect_block(file_inode, &total_remaining_blocks,
1397                                     &no_blks_reqd);
1398         alloc_double_indirect_block(file_inode, &total_remaining_blocks,
1399                                     &no_blks_reqd);
1400         alloc_triple_indirect_block(file_inode, &total_remaining_blocks,
1401                                     &no_blks_reqd);
1402         *total_no_of_block += no_blks_reqd;
1403 }
1404
1405 #endif
1406
1407 static struct ext4_extent_header *ext4fs_get_extent_block
1408         (struct ext2_data *data, char *buf,
1409                 struct ext4_extent_header *ext_block,
1410                 uint32_t fileblock, int log2_blksz)
1411 {
1412         struct ext4_extent_idx *index;
1413         unsigned long long block;
1414         int blksz = EXT2_BLOCK_SIZE(data);
1415         int i;
1416
1417         while (1) {
1418                 index = (struct ext4_extent_idx *)(ext_block + 1);
1419
1420                 if (le16_to_cpu(ext_block->eh_magic) != EXT4_EXT_MAGIC)
1421                         return 0;
1422
1423                 if (ext_block->eh_depth == 0)
1424                         return ext_block;
1425                 i = -1;
1426                 do {
1427                         i++;
1428                         if (i >= le16_to_cpu(ext_block->eh_entries))
1429                                 break;
1430                 } while (fileblock >= le32_to_cpu(index[i].ei_block));
1431
1432                 if (--i < 0)
1433                         return 0;
1434
1435                 block = le16_to_cpu(index[i].ei_leaf_hi);
1436                 block = (block << 32) + le32_to_cpu(index[i].ei_leaf_lo);
1437
1438                 if (ext4fs_devread((lbaint_t)block << log2_blksz, 0, blksz,
1439                                    buf))
1440                         ext_block = (struct ext4_extent_header *)buf;
1441                 else
1442                         return 0;
1443         }
1444 }
1445
1446 static int ext4fs_blockgroup
1447         (struct ext2_data *data, int group, struct ext2_block_group *blkgrp)
1448 {
1449         long int blkno;
1450         unsigned int blkoff, desc_per_blk;
1451         int log2blksz = get_fs()->dev_desc->log2blksz;
1452
1453         desc_per_blk = EXT2_BLOCK_SIZE(data) / sizeof(struct ext2_block_group);
1454
1455         blkno = __le32_to_cpu(data->sblock.first_data_block) + 1 +
1456                         group / desc_per_blk;
1457         blkoff = (group % desc_per_blk) * sizeof(struct ext2_block_group);
1458
1459         debug("ext4fs read %d group descriptor (blkno %ld blkoff %u)\n",
1460               group, blkno, blkoff);
1461
1462         return ext4fs_devread((lbaint_t)blkno <<
1463                               (LOG2_BLOCK_SIZE(data) - log2blksz),
1464                               blkoff, sizeof(struct ext2_block_group),
1465                               (char *)blkgrp);
1466 }
1467
1468 int ext4fs_read_inode(struct ext2_data *data, int ino, struct ext2_inode *inode)
1469 {
1470         struct ext2_block_group blkgrp;
1471         struct ext2_sblock *sblock = &data->sblock;
1472         struct ext_filesystem *fs = get_fs();
1473         int log2blksz = get_fs()->dev_desc->log2blksz;
1474         int inodes_per_block, status;
1475         long int blkno;
1476         unsigned int blkoff;
1477
1478         /* It is easier to calculate if the first inode is 0. */
1479         ino--;
1480         status = ext4fs_blockgroup(data, ino / __le32_to_cpu
1481                                    (sblock->inodes_per_group), &blkgrp);
1482         if (status == 0)
1483                 return 0;
1484
1485         inodes_per_block = EXT2_BLOCK_SIZE(data) / fs->inodesz;
1486         blkno = __le32_to_cpu(blkgrp.inode_table_id) +
1487             (ino % __le32_to_cpu(sblock->inodes_per_group)) / inodes_per_block;
1488         blkoff = (ino % inodes_per_block) * fs->inodesz;
1489         /* Read the inode. */
1490         status = ext4fs_devread((lbaint_t)blkno << (LOG2_BLOCK_SIZE(data) -
1491                                 log2blksz), blkoff,
1492                                 sizeof(struct ext2_inode), (char *)inode);
1493         if (status == 0)
1494                 return 0;
1495
1496         return 1;
1497 }
1498
1499 long int read_allocated_block(struct ext2_inode *inode, int fileblock)
1500 {
1501         long int blknr;
1502         int blksz;
1503         int log2_blksz;
1504         int status;
1505         long int rblock;
1506         long int perblock_parent;
1507         long int perblock_child;
1508         unsigned long long start;
1509         /* get the blocksize of the filesystem */
1510         blksz = EXT2_BLOCK_SIZE(ext4fs_root);
1511         log2_blksz = LOG2_BLOCK_SIZE(ext4fs_root)
1512                 - get_fs()->dev_desc->log2blksz;
1513
1514         if (le32_to_cpu(inode->flags) & EXT4_EXTENTS_FL) {
1515                 char *buf = zalloc(blksz);
1516                 if (!buf)
1517                         return -ENOMEM;
1518                 struct ext4_extent_header *ext_block;
1519                 struct ext4_extent *extent;
1520                 int i = -1;
1521                 ext_block =
1522                         ext4fs_get_extent_block(ext4fs_root, buf,
1523                                                 (struct ext4_extent_header *)
1524                                                 inode->b.blocks.dir_blocks,
1525                                                 fileblock, log2_blksz);
1526                 if (!ext_block) {
1527                         printf("invalid extent block\n");
1528                         free(buf);
1529                         return -EINVAL;
1530                 }
1531
1532                 extent = (struct ext4_extent *)(ext_block + 1);
1533
1534                 do {
1535                         i++;
1536                         if (i >= le16_to_cpu(ext_block->eh_entries))
1537                                 break;
1538                 } while (fileblock >= le32_to_cpu(extent[i].ee_block));
1539                 if (--i >= 0) {
1540                         fileblock -= le32_to_cpu(extent[i].ee_block);
1541                         if (fileblock >= le16_to_cpu(extent[i].ee_len)) {
1542                                 free(buf);
1543                                 return 0;
1544                         }
1545
1546                         start = le16_to_cpu(extent[i].ee_start_hi);
1547                         start = (start << 32) +
1548                                         le32_to_cpu(extent[i].ee_start_lo);
1549                         free(buf);
1550                         return fileblock + start;
1551                 }
1552
1553                 printf("Extent Error\n");
1554                 free(buf);
1555                 return -1;
1556         }
1557
1558         /* Direct blocks. */
1559         if (fileblock < INDIRECT_BLOCKS)
1560                 blknr = __le32_to_cpu(inode->b.blocks.dir_blocks[fileblock]);
1561
1562         /* Indirect. */
1563         else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4))) {
1564                 if (ext4fs_indir1_block == NULL) {
1565                         ext4fs_indir1_block = zalloc(blksz);
1566                         if (ext4fs_indir1_block == NULL) {
1567                                 printf("** SI ext2fs read block (indir 1)"
1568                                         "malloc failed. **\n");
1569                                 return -1;
1570                         }
1571                         ext4fs_indir1_size = blksz;
1572                         ext4fs_indir1_blkno = -1;
1573                 }
1574                 if (blksz != ext4fs_indir1_size) {
1575                         free(ext4fs_indir1_block);
1576                         ext4fs_indir1_block = NULL;
1577                         ext4fs_indir1_size = 0;
1578                         ext4fs_indir1_blkno = -1;
1579                         ext4fs_indir1_block = zalloc(blksz);
1580                         if (ext4fs_indir1_block == NULL) {
1581                                 printf("** SI ext2fs read block (indir 1):"
1582                                         "malloc failed. **\n");
1583                                 return -1;
1584                         }
1585                         ext4fs_indir1_size = blksz;
1586                 }
1587                 if ((__le32_to_cpu(inode->b.blocks.indir_block) <<
1588                      log2_blksz) != ext4fs_indir1_blkno) {
1589                         status =
1590                             ext4fs_devread((lbaint_t)__le32_to_cpu
1591                                            (inode->b.blocks.
1592                                             indir_block) << log2_blksz, 0,
1593                                            blksz, (char *)ext4fs_indir1_block);
1594                         if (status == 0) {
1595                                 printf("** SI ext2fs read block (indir 1)"
1596                                         "failed. **\n");
1597                                 return 0;
1598                         }
1599                         ext4fs_indir1_blkno =
1600                                 __le32_to_cpu(inode->b.blocks.
1601                                                indir_block) << log2_blksz;
1602                 }
1603                 blknr = __le32_to_cpu(ext4fs_indir1_block
1604                                       [fileblock - INDIRECT_BLOCKS]);
1605         }
1606         /* Double indirect. */
1607         else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4 *
1608                                         (blksz / 4 + 1)))) {
1609
1610                 long int perblock = blksz / 4;
1611                 long int rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4);
1612
1613                 if (ext4fs_indir1_block == NULL) {
1614                         ext4fs_indir1_block = zalloc(blksz);
1615                         if (ext4fs_indir1_block == NULL) {
1616                                 printf("** DI ext2fs read block (indir 2 1)"
1617                                         "malloc failed. **\n");
1618                                 return -1;
1619                         }
1620                         ext4fs_indir1_size = blksz;
1621                         ext4fs_indir1_blkno = -1;
1622                 }
1623                 if (blksz != ext4fs_indir1_size) {
1624                         free(ext4fs_indir1_block);
1625                         ext4fs_indir1_block = NULL;
1626                         ext4fs_indir1_size = 0;
1627                         ext4fs_indir1_blkno = -1;
1628                         ext4fs_indir1_block = zalloc(blksz);
1629                         if (ext4fs_indir1_block == NULL) {
1630                                 printf("** DI ext2fs read block (indir 2 1)"
1631                                         "malloc failed. **\n");
1632                                 return -1;
1633                         }
1634                         ext4fs_indir1_size = blksz;
1635                 }
1636                 if ((__le32_to_cpu(inode->b.blocks.double_indir_block) <<
1637                      log2_blksz) != ext4fs_indir1_blkno) {
1638                         status =
1639                             ext4fs_devread((lbaint_t)__le32_to_cpu
1640                                            (inode->b.blocks.
1641                                             double_indir_block) << log2_blksz,
1642                                            0, blksz,
1643                                            (char *)ext4fs_indir1_block);
1644                         if (status == 0) {
1645                                 printf("** DI ext2fs read block (indir 2 1)"
1646                                         "failed. **\n");
1647                                 return -1;
1648                         }
1649                         ext4fs_indir1_blkno =
1650                             __le32_to_cpu(inode->b.blocks.double_indir_block) <<
1651                             log2_blksz;
1652                 }
1653
1654                 if (ext4fs_indir2_block == NULL) {
1655                         ext4fs_indir2_block = zalloc(blksz);
1656                         if (ext4fs_indir2_block == NULL) {
1657                                 printf("** DI ext2fs read block (indir 2 2)"
1658                                         "malloc failed. **\n");
1659                                 return -1;
1660                         }
1661                         ext4fs_indir2_size = blksz;
1662                         ext4fs_indir2_blkno = -1;
1663                 }
1664                 if (blksz != ext4fs_indir2_size) {
1665                         free(ext4fs_indir2_block);
1666                         ext4fs_indir2_block = NULL;
1667                         ext4fs_indir2_size = 0;
1668                         ext4fs_indir2_blkno = -1;
1669                         ext4fs_indir2_block = zalloc(blksz);
1670                         if (ext4fs_indir2_block == NULL) {
1671                                 printf("** DI ext2fs read block (indir 2 2)"
1672                                         "malloc failed. **\n");
1673                                 return -1;
1674                         }
1675                         ext4fs_indir2_size = blksz;
1676                 }
1677                 if ((__le32_to_cpu(ext4fs_indir1_block[rblock / perblock]) <<
1678                      log2_blksz) != ext4fs_indir2_blkno) {
1679                         status = ext4fs_devread((lbaint_t)__le32_to_cpu
1680                                                 (ext4fs_indir1_block
1681                                                  [rblock /
1682                                                   perblock]) << log2_blksz, 0,
1683                                                 blksz,
1684                                                 (char *)ext4fs_indir2_block);
1685                         if (status == 0) {
1686                                 printf("** DI ext2fs read block (indir 2 2)"
1687                                         "failed. **\n");
1688                                 return -1;
1689                         }
1690                         ext4fs_indir2_blkno =
1691                             __le32_to_cpu(ext4fs_indir1_block[rblock
1692                                                               /
1693                                                               perblock]) <<
1694                             log2_blksz;
1695                 }
1696                 blknr = __le32_to_cpu(ext4fs_indir2_block[rblock % perblock]);
1697         }
1698         /* Tripple indirect. */
1699         else {
1700                 rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4 +
1701                                       (blksz / 4 * blksz / 4));
1702                 perblock_child = blksz / 4;
1703                 perblock_parent = ((blksz / 4) * (blksz / 4));
1704
1705                 if (ext4fs_indir1_block == NULL) {
1706                         ext4fs_indir1_block = zalloc(blksz);
1707                         if (ext4fs_indir1_block == NULL) {
1708                                 printf("** TI ext2fs read block (indir 2 1)"
1709                                         "malloc failed. **\n");
1710                                 return -1;
1711                         }
1712                         ext4fs_indir1_size = blksz;
1713                         ext4fs_indir1_blkno = -1;
1714                 }
1715                 if (blksz != ext4fs_indir1_size) {
1716                         free(ext4fs_indir1_block);
1717                         ext4fs_indir1_block = NULL;
1718                         ext4fs_indir1_size = 0;
1719                         ext4fs_indir1_blkno = -1;
1720                         ext4fs_indir1_block = zalloc(blksz);
1721                         if (ext4fs_indir1_block == NULL) {
1722                                 printf("** TI ext2fs read block (indir 2 1)"
1723                                         "malloc failed. **\n");
1724                                 return -1;
1725                         }
1726                         ext4fs_indir1_size = blksz;
1727                 }
1728                 if ((__le32_to_cpu(inode->b.blocks.triple_indir_block) <<
1729                      log2_blksz) != ext4fs_indir1_blkno) {
1730                         status = ext4fs_devread
1731                             ((lbaint_t)
1732                              __le32_to_cpu(inode->b.blocks.triple_indir_block)
1733                              << log2_blksz, 0, blksz,
1734                              (char *)ext4fs_indir1_block);
1735                         if (status == 0) {
1736                                 printf("** TI ext2fs read block (indir 2 1)"
1737                                         "failed. **\n");
1738                                 return -1;
1739                         }
1740                         ext4fs_indir1_blkno =
1741                             __le32_to_cpu(inode->b.blocks.triple_indir_block) <<
1742                             log2_blksz;
1743                 }
1744
1745                 if (ext4fs_indir2_block == NULL) {
1746                         ext4fs_indir2_block = zalloc(blksz);
1747                         if (ext4fs_indir2_block == NULL) {
1748                                 printf("** TI ext2fs read block (indir 2 2)"
1749                                         "malloc failed. **\n");
1750                                 return -1;
1751                         }
1752                         ext4fs_indir2_size = blksz;
1753                         ext4fs_indir2_blkno = -1;
1754                 }
1755                 if (blksz != ext4fs_indir2_size) {
1756                         free(ext4fs_indir2_block);
1757                         ext4fs_indir2_block = NULL;
1758                         ext4fs_indir2_size = 0;
1759                         ext4fs_indir2_blkno = -1;
1760                         ext4fs_indir2_block = zalloc(blksz);
1761                         if (ext4fs_indir2_block == NULL) {
1762                                 printf("** TI ext2fs read block (indir 2 2)"
1763                                         "malloc failed. **\n");
1764                                 return -1;
1765                         }
1766                         ext4fs_indir2_size = blksz;
1767                 }
1768                 if ((__le32_to_cpu(ext4fs_indir1_block[rblock /
1769                                                        perblock_parent]) <<
1770                      log2_blksz)
1771                     != ext4fs_indir2_blkno) {
1772                         status = ext4fs_devread((lbaint_t)__le32_to_cpu
1773                                                 (ext4fs_indir1_block
1774                                                  [rblock /
1775                                                   perblock_parent]) <<
1776                                                 log2_blksz, 0, blksz,
1777                                                 (char *)ext4fs_indir2_block);
1778                         if (status == 0) {
1779                                 printf("** TI ext2fs read block (indir 2 2)"
1780                                         "failed. **\n");
1781                                 return -1;
1782                         }
1783                         ext4fs_indir2_blkno =
1784                             __le32_to_cpu(ext4fs_indir1_block[rblock /
1785                                                               perblock_parent])
1786                             << log2_blksz;
1787                 }
1788
1789                 if (ext4fs_indir3_block == NULL) {
1790                         ext4fs_indir3_block = zalloc(blksz);
1791                         if (ext4fs_indir3_block == NULL) {
1792                                 printf("** TI ext2fs read block (indir 2 2)"
1793                                         "malloc failed. **\n");
1794                                 return -1;
1795                         }
1796                         ext4fs_indir3_size = blksz;
1797                         ext4fs_indir3_blkno = -1;
1798                 }
1799                 if (blksz != ext4fs_indir3_size) {
1800                         free(ext4fs_indir3_block);
1801                         ext4fs_indir3_block = NULL;
1802                         ext4fs_indir3_size = 0;
1803                         ext4fs_indir3_blkno = -1;
1804                         ext4fs_indir3_block = zalloc(blksz);
1805                         if (ext4fs_indir3_block == NULL) {
1806                                 printf("** TI ext2fs read block (indir 2 2)"
1807                                         "malloc failed. **\n");
1808                                 return -1;
1809                         }
1810                         ext4fs_indir3_size = blksz;
1811                 }
1812                 if ((__le32_to_cpu(ext4fs_indir2_block[rblock
1813                                                        /
1814                                                        perblock_child]) <<
1815                      log2_blksz) != ext4fs_indir3_blkno) {
1816                         status =
1817                             ext4fs_devread((lbaint_t)__le32_to_cpu
1818                                            (ext4fs_indir2_block
1819                                             [(rblock / perblock_child)
1820                                              % (blksz / 4)]) << log2_blksz, 0,
1821                                            blksz, (char *)ext4fs_indir3_block);
1822                         if (status == 0) {
1823                                 printf("** TI ext2fs read block (indir 2 2)"
1824                                        "failed. **\n");
1825                                 return -1;
1826                         }
1827                         ext4fs_indir3_blkno =
1828                             __le32_to_cpu(ext4fs_indir2_block[(rblock /
1829                                                                perblock_child) %
1830                                                               (blksz /
1831                                                                4)]) <<
1832                             log2_blksz;
1833                 }
1834
1835                 blknr = __le32_to_cpu(ext4fs_indir3_block
1836                                       [rblock % perblock_child]);
1837         }
1838         debug("read_allocated_block %ld\n", blknr);
1839
1840         return blknr;
1841 }
1842
1843 /**
1844  * ext4fs_reinit_global() - Reinitialize values of ext4 write implementation's
1845  *                          global pointers
1846  *
1847  * This function assures that for a file with the same name but different size
1848  * the sequential store on the ext4 filesystem will be correct.
1849  *
1850  * In this function the global data, responsible for internal representation
1851  * of the ext4 data are initialized to the reset state. Without this, during
1852  * replacement of the smaller file with the bigger truncation of new file was
1853  * performed.
1854  */
1855 void ext4fs_reinit_global(void)
1856 {
1857         if (ext4fs_indir1_block != NULL) {
1858                 free(ext4fs_indir1_block);
1859                 ext4fs_indir1_block = NULL;
1860                 ext4fs_indir1_size = 0;
1861                 ext4fs_indir1_blkno = -1;
1862         }
1863         if (ext4fs_indir2_block != NULL) {
1864                 free(ext4fs_indir2_block);
1865                 ext4fs_indir2_block = NULL;
1866                 ext4fs_indir2_size = 0;
1867                 ext4fs_indir2_blkno = -1;
1868         }
1869         if (ext4fs_indir3_block != NULL) {
1870                 free(ext4fs_indir3_block);
1871                 ext4fs_indir3_block = NULL;
1872                 ext4fs_indir3_size = 0;
1873                 ext4fs_indir3_blkno = -1;
1874         }
1875 }
1876 void ext4fs_close(void)
1877 {
1878         if ((ext4fs_file != NULL) && (ext4fs_root != NULL)) {
1879                 ext4fs_free_node(ext4fs_file, &ext4fs_root->diropen);
1880                 ext4fs_file = NULL;
1881         }
1882         if (ext4fs_root != NULL) {
1883                 free(ext4fs_root);
1884                 ext4fs_root = NULL;
1885         }
1886
1887         ext4fs_reinit_global();
1888 }
1889
1890 int ext4fs_iterate_dir(struct ext2fs_node *dir, char *name,
1891                                 struct ext2fs_node **fnode, int *ftype)
1892 {
1893         unsigned int fpos = 0;
1894         int status;
1895         loff_t actread;
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, &actread);
1914                 if (status < 0)
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                                                   &actread);
1927                         if (status < 0)
1928                                 return 0;
1929
1930                         fdiro = zalloc(sizeof(struct ext2fs_node));
1931                         if (!fdiro)
1932                                 return 0;
1933
1934                         fdiro->data = diro->data;
1935                         fdiro->ino = __le32_to_cpu(dirent.inode);
1936
1937                         filename[dirent.namelen] = '\0';
1938
1939                         if (dirent.filetype != FILETYPE_UNKNOWN) {
1940                                 fdiro->inode_read = 0;
1941
1942                                 if (dirent.filetype == FILETYPE_DIRECTORY)
1943                                         type = FILETYPE_DIRECTORY;
1944                                 else if (dirent.filetype == FILETYPE_SYMLINK)
1945                                         type = FILETYPE_SYMLINK;
1946                                 else if (dirent.filetype == FILETYPE_REG)
1947                                         type = FILETYPE_REG;
1948                         } else {
1949                                 status = ext4fs_read_inode(diro->data,
1950                                                            __le32_to_cpu
1951                                                            (dirent.inode),
1952                                                            &fdiro->inode);
1953                                 if (status == 0) {
1954                                         free(fdiro);
1955                                         return 0;
1956                                 }
1957                                 fdiro->inode_read = 1;
1958
1959                                 if ((__le16_to_cpu(fdiro->inode.mode) &
1960                                      FILETYPE_INO_MASK) ==
1961                                     FILETYPE_INO_DIRECTORY) {
1962                                         type = FILETYPE_DIRECTORY;
1963                                 } else if ((__le16_to_cpu(fdiro->inode.mode)
1964                                             & FILETYPE_INO_MASK) ==
1965                                            FILETYPE_INO_SYMLINK) {
1966                                         type = FILETYPE_SYMLINK;
1967                                 } else if ((__le16_to_cpu(fdiro->inode.mode)
1968                                             & FILETYPE_INO_MASK) ==
1969                                            FILETYPE_INO_REG) {
1970                                         type = FILETYPE_REG;
1971                                 }
1972                         }
1973 #ifdef DEBUG
1974                         printf("iterate >%s<\n", filename);
1975 #endif /* of DEBUG */
1976                         if ((name != NULL) && (fnode != NULL)
1977                             && (ftype != NULL)) {
1978                                 if (strcmp(filename, name) == 0) {
1979                                         *ftype = type;
1980                                         *fnode = fdiro;
1981                                         return 1;
1982                                 }
1983                         } else {
1984                                 if (fdiro->inode_read == 0) {
1985                                         status = ext4fs_read_inode(diro->data,
1986                                                                  __le32_to_cpu(
1987                                                                  dirent.inode),
1988                                                                  &fdiro->inode);
1989                                         if (status == 0) {
1990                                                 free(fdiro);
1991                                                 return 0;
1992                                         }
1993                                         fdiro->inode_read = 1;
1994                                 }
1995                                 switch (type) {
1996                                 case FILETYPE_DIRECTORY:
1997                                         printf("<DIR> ");
1998                                         break;
1999                                 case FILETYPE_SYMLINK:
2000                                         printf("<SYM> ");
2001                                         break;
2002                                 case FILETYPE_REG:
2003                                         printf("      ");
2004                                         break;
2005                                 default:
2006                                         printf("< ? > ");
2007                                         break;
2008                                 }
2009                                 printf("%10u %s\n",
2010                                        __le32_to_cpu(fdiro->inode.size),
2011                                         filename);
2012                         }
2013                         free(fdiro);
2014                 }
2015                 fpos += __le16_to_cpu(dirent.direntlen);
2016         }
2017         return 0;
2018 }
2019
2020 static char *ext4fs_read_symlink(struct ext2fs_node *node)
2021 {
2022         char *symlink;
2023         struct ext2fs_node *diro = node;
2024         int status;
2025         loff_t actread;
2026
2027         if (!diro->inode_read) {
2028                 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode);
2029                 if (status == 0)
2030                         return 0;
2031         }
2032         symlink = zalloc(__le32_to_cpu(diro->inode.size) + 1);
2033         if (!symlink)
2034                 return 0;
2035
2036         if (__le32_to_cpu(diro->inode.size) <= 60) {
2037                 strncpy(symlink, diro->inode.b.symlink,
2038                          __le32_to_cpu(diro->inode.size));
2039         } else {
2040                 status = ext4fs_read_file(diro, 0,
2041                                            __le32_to_cpu(diro->inode.size),
2042                                            symlink, &actread);
2043                 if (status == 0) {
2044                         free(symlink);
2045                         return 0;
2046                 }
2047         }
2048         symlink[__le32_to_cpu(diro->inode.size)] = '\0';
2049         return symlink;
2050 }
2051
2052 static int ext4fs_find_file1(const char *currpath,
2053                              struct ext2fs_node *currroot,
2054                              struct ext2fs_node **currfound, int *foundtype)
2055 {
2056         char fpath[strlen(currpath) + 1];
2057         char *name = fpath;
2058         char *next;
2059         int status;
2060         int type = FILETYPE_DIRECTORY;
2061         struct ext2fs_node *currnode = currroot;
2062         struct ext2fs_node *oldnode = currroot;
2063
2064         strncpy(fpath, currpath, strlen(currpath) + 1);
2065
2066         /* Remove all leading slashes. */
2067         while (*name == '/')
2068                 name++;
2069
2070         if (!*name) {
2071                 *currfound = currnode;
2072                 return 1;
2073         }
2074
2075         for (;;) {
2076                 int found;
2077
2078                 /* Extract the actual part from the pathname. */
2079                 next = strchr(name, '/');
2080                 if (next) {
2081                         /* Remove all leading slashes. */
2082                         while (*next == '/')
2083                                 *(next++) = '\0';
2084                 }
2085
2086                 if (type != FILETYPE_DIRECTORY) {
2087                         ext4fs_free_node(currnode, currroot);
2088                         return 0;
2089                 }
2090
2091                 oldnode = currnode;
2092
2093                 /* Iterate over the directory. */
2094                 found = ext4fs_iterate_dir(currnode, name, &currnode, &type);
2095                 if (found == 0)
2096                         return 0;
2097
2098                 if (found == -1)
2099                         break;
2100
2101                 /* Read in the symlink and follow it. */
2102                 if (type == FILETYPE_SYMLINK) {
2103                         char *symlink;
2104
2105                         /* Test if the symlink does not loop. */
2106                         if (++symlinknest == 8) {
2107                                 ext4fs_free_node(currnode, currroot);
2108                                 ext4fs_free_node(oldnode, currroot);
2109                                 return 0;
2110                         }
2111
2112                         symlink = ext4fs_read_symlink(currnode);
2113                         ext4fs_free_node(currnode, currroot);
2114
2115                         if (!symlink) {
2116                                 ext4fs_free_node(oldnode, currroot);
2117                                 return 0;
2118                         }
2119
2120                         debug("Got symlink >%s<\n", symlink);
2121
2122                         if (symlink[0] == '/') {
2123                                 ext4fs_free_node(oldnode, currroot);
2124                                 oldnode = &ext4fs_root->diropen;
2125                         }
2126
2127                         /* Lookup the node the symlink points to. */
2128                         status = ext4fs_find_file1(symlink, oldnode,
2129                                                     &currnode, &type);
2130
2131                         free(symlink);
2132
2133                         if (status == 0) {
2134                                 ext4fs_free_node(oldnode, currroot);
2135                                 return 0;
2136                         }
2137                 }
2138
2139                 ext4fs_free_node(oldnode, currroot);
2140
2141                 /* Found the node! */
2142                 if (!next || *next == '\0') {
2143                         *currfound = currnode;
2144                         *foundtype = type;
2145                         return 1;
2146                 }
2147                 name = next;
2148         }
2149         return -1;
2150 }
2151
2152 int ext4fs_find_file(const char *path, struct ext2fs_node *rootnode,
2153         struct ext2fs_node **foundnode, int expecttype)
2154 {
2155         int status;
2156         int foundtype = FILETYPE_DIRECTORY;
2157
2158         symlinknest = 0;
2159         if (!path)
2160                 return 0;
2161
2162         status = ext4fs_find_file1(path, rootnode, foundnode, &foundtype);
2163         if (status == 0)
2164                 return 0;
2165
2166         /* Check if the node that was found was of the expected type. */
2167         if ((expecttype == FILETYPE_REG) && (foundtype != expecttype))
2168                 return 0;
2169         else if ((expecttype == FILETYPE_DIRECTORY)
2170                    && (foundtype != expecttype))
2171                 return 0;
2172
2173         return 1;
2174 }
2175
2176 int ext4fs_open(const char *filename, loff_t *len)
2177 {
2178         struct ext2fs_node *fdiro = NULL;
2179         int status;
2180
2181         if (ext4fs_root == NULL)
2182                 return -1;
2183
2184         ext4fs_file = NULL;
2185         status = ext4fs_find_file(filename, &ext4fs_root->diropen, &fdiro,
2186                                   FILETYPE_REG);
2187         if (status == 0)
2188                 goto fail;
2189
2190         if (!fdiro->inode_read) {
2191                 status = ext4fs_read_inode(fdiro->data, fdiro->ino,
2192                                 &fdiro->inode);
2193                 if (status == 0)
2194                         goto fail;
2195         }
2196         *len = __le32_to_cpu(fdiro->inode.size);
2197         ext4fs_file = fdiro;
2198
2199         return 0;
2200 fail:
2201         ext4fs_free_node(fdiro, &ext4fs_root->diropen);
2202
2203         return -1;
2204 }
2205
2206 int ext4fs_mount(unsigned part_length)
2207 {
2208         struct ext2_data *data;
2209         int status;
2210         struct ext_filesystem *fs = get_fs();
2211         data = zalloc(SUPERBLOCK_SIZE);
2212         if (!data)
2213                 return 0;
2214
2215         /* Read the superblock. */
2216         status = ext4_read_superblock((char *)&data->sblock);
2217
2218         if (status == 0)
2219                 goto fail;
2220
2221         /* Make sure this is an ext2 filesystem. */
2222         if (__le16_to_cpu(data->sblock.magic) != EXT2_MAGIC)
2223                 goto fail;
2224
2225         if (__le32_to_cpu(data->sblock.revision_level == 0))
2226                 fs->inodesz = 128;
2227         else
2228                 fs->inodesz = __le16_to_cpu(data->sblock.inode_size);
2229
2230         debug("EXT2 rev %d, inode_size %d\n",
2231                __le32_to_cpu(data->sblock.revision_level), fs->inodesz);
2232
2233         data->diropen.data = data;
2234         data->diropen.ino = 2;
2235         data->diropen.inode_read = 1;
2236         data->inode = &data->diropen.inode;
2237
2238         status = ext4fs_read_inode(data, 2, data->inode);
2239         if (status == 0)
2240                 goto fail;
2241
2242         ext4fs_root = data;
2243
2244         return 1;
2245 fail:
2246         printf("Failed to mount ext2 filesystem...\n");
2247         free(data);
2248         ext4fs_root = NULL;
2249
2250         return 0;
2251 }