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 <memalign.h>
  28 #include <stddef.h>
  29 #include <linux/stat.h>
  30 #include <linux/time.h>
  31 #include <asm/byteorder.h>
  32 #include "ext4_common.h"
  33
  34 struct ext2_data *ext4fs_root;
  35 struct ext2fs_node *ext4fs_file;
  36 uint32_t *ext4fs_indir1_block;
  37 int ext4fs_indir1_size;
  38 int ext4fs_indir1_blkno = -1;
  39 uint32_t *ext4fs_indir2_block;
  40 int ext4fs_indir2_size;
  41 int ext4fs_indir2_blkno = -1;
  42
  43 uint32_t *ext4fs_indir3_block;
  44 int ext4fs_indir3_size;
  45 int ext4fs_indir3_blkno = -1;
  46 struct ext2_inode *g_parent_inode;
  47 static int symlinknest;
  48
  49 #if defined(CONFIG_EXT4_WRITE)
  50 uint32_t ext4fs_div_roundup(uint32_t size, uint32_t n)
  51 {
  52         uint32_t res = size / n;
  53         if (res * n != size)
  54                 res++;
  55
  56         return res;
  57 }
  58
  59 void put_ext4(uint64_t off, void *buf, uint32_t size)
  60 {
  61         uint64_t startblock;
  62         uint64_t remainder;
  63         unsigned char *temp_ptr = NULL;
  64         struct ext_filesystem *fs = get_fs();
  65         int log2blksz = fs->dev_desc->log2blksz;
  66         ALLOC_CACHE_ALIGN_BUFFER(unsigned char, sec_buf, fs->dev_desc->blksz);
  67
  68         startblock = off >> log2blksz;
  69         startblock += part_offset;
  70         remainder = off & (uint64_t)(fs->dev_desc->blksz - 1);
  71
  72         if (fs->dev_desc == NULL)
  73                 return;
  74
  75         if ((startblock + (size >> log2blksz)) >
  76             (part_offset + fs->total_sect)) {
  77                 printf("part_offset is " LBAFU "\n", part_offset);
  78                 printf("total_sector is %" PRIu64 "\n", fs->total_sect);
  79                 printf("error: overflow occurs\n");
  80                 return;
  81         }
  82
  83         if (remainder) {
  84                 if (fs->dev_desc->block_read) {
  85                         fs->dev_desc->block_read(fs->dev_desc->dev,
  86                                                  startblock, 1, sec_buf);
  87                         temp_ptr = sec_buf;
  88                         memcpy((temp_ptr + remainder),
  89                                (unsigned char *)buf, size);
  90                         fs->dev_desc->block_write(fs->dev_desc->dev,
  91                                                   startblock, 1, sec_buf);
  92                 }
  93         } else {
  94                 if (size >> log2blksz != 0) {
  95                         fs->dev_desc->block_write(fs->dev_desc->dev,
  96                                                   startblock,
  97                                                   size >> log2blksz,
  98                                                   (unsigned long *)buf);
  99                 } else {
 100                         fs->dev_desc->block_read(fs->dev_desc->dev,
 101                                                  startblock, 1, sec_buf);
 102                         temp_ptr = sec_buf;
 103                         memcpy(temp_ptr, buf, size);
 104                         fs->dev_desc->block_write(fs->dev_desc->dev,
 105                                                   startblock, 1,
 106                                                   (unsigned long *)sec_buf);
 107                 }
 108         }
 109 }
 110
 111 static int _get_new_inode_no(unsigned char *buffer)
 112 {
 113         struct ext_filesystem *fs = get_fs();
 114         unsigned char input;
 115         int operand, status;
 116         int count = 1;
 117         int j = 0;
 118
 119         /* get the blocksize of the filesystem */
 120         unsigned char *ptr = buffer;
 121         while (*ptr == 255) {
 122                 ptr++;
 123                 count += 8;
 124                 if (count > ext4fs_root->sblock.inodes_per_group)
 125                         return -1;
 126         }
 127
 128         for (j = 0; j < fs->blksz; j++) {
 129                 input = *ptr;
 130                 int i = 0;
 131                 while (i <= 7) {
 132                         operand = 1 << i;
 133                         status = input & operand;
 134                         if (status) {
 135                                 i++;
 136                                 count++;
 137                         } else {
 138                                 *ptr |= operand;
 139                                 return count;
 140                         }
 141                 }
 142                 ptr = ptr + 1;
 143         }
 144
 145         return -1;
 146 }
 147
 148 static int _get_new_blk_no(unsigned char *buffer)
 149 {
 150         unsigned char input;
 151         int operand, status;
 152         int count = 0;
 153         int j = 0;
 154         unsigned char *ptr = buffer;
 155         struct ext_filesystem *fs = get_fs();
 156
 157         if (fs->blksz != 1024)
 158                 count = 0;
 159         else
 160                 count = 1;
 161
 162         while (*ptr == 255) {
 163                 ptr++;
 164                 count += 8;
 165                 if (count == (fs->blksz * 8))
 166                         return -1;
 167         }
 168
 169         for (j = 0; j < fs->blksz; j++) {
 170                 input = *ptr;
 171                 int i = 0;
 172                 while (i <= 7) {
 173                         operand = 1 << i;
 174                         status = input & operand;
 175                         if (status) {
 176                                 i++;
 177                                 count++;
 178                         } else {
 179                                 *ptr |= operand;
 180                                 return count;
 181                         }
 182                 }
 183                 ptr = ptr + 1;
 184         }
 185
 186         return -1;
 187 }
 188
 189 int ext4fs_set_block_bmap(long int blockno, unsigned char *buffer, int index)
 190 {
 191         int i, remainder, status;
 192         unsigned char *ptr = buffer;
 193         unsigned char operand;
 194         i = blockno / 8;
 195         remainder = blockno % 8;
 196         int blocksize = EXT2_BLOCK_SIZE(ext4fs_root);
 197
 198         i = i - (index * blocksize);
 199         if (blocksize != 1024) {
 200                 ptr = ptr + i;
 201                 operand = 1 << remainder;
 202                 status = *ptr & operand;
 203                 if (status)
 204                         return -1;
 205
 206                 *ptr = *ptr | operand;
 207                 return 0;
 208         } else {
 209                 if (remainder == 0) {
 210                         ptr = ptr + i - 1;
 211                         operand = (1 << 7);
 212                 } else {
 213                         ptr = ptr + i;
 214                         operand = (1 << (remainder - 1));
 215                 }
 216                 status = *ptr & operand;
 217                 if (status)
 218                         return -1;
 219
 220                 *ptr = *ptr | operand;
 221                 return 0;
 222         }
 223 }
 224
 225 void ext4fs_reset_block_bmap(long int blockno, unsigned char *buffer, int index)
 226 {
 227         int i, remainder, status;
 228         unsigned char *ptr = buffer;
 229         unsigned char operand;
 230         i = blockno / 8;
 231         remainder = blockno % 8;
 232         int blocksize = EXT2_BLOCK_SIZE(ext4fs_root);
 233
 234         i = i - (index * blocksize);
 235         if (blocksize != 1024) {
 236                 ptr = ptr + i;
 237                 operand = (1 << remainder);
 238                 status = *ptr & operand;
 239                 if (status)
 240                         *ptr = *ptr & ~(operand);
 241         } else {
 242                 if (remainder == 0) {
 243                         ptr = ptr + i - 1;
 244                         operand = (1 << 7);
 245                 } else {
 246                         ptr = ptr + i;
 247                         operand = (1 << (remainder - 1));
 248                 }
 249                 status = *ptr & operand;
 250                 if (status)
 251                         *ptr = *ptr & ~(operand);
 252         }
 253 }
 254
 255 int ext4fs_set_inode_bmap(int inode_no, unsigned char *buffer, int index)
 256 {
 257         int i, remainder, status;
 258         unsigned char *ptr = buffer;
 259         unsigned char operand;
 260
 261         inode_no -= (index * ext4fs_root->sblock.inodes_per_group);
 262         i = inode_no / 8;
 263         remainder = inode_no % 8;
 264         if (remainder == 0) {
 265                 ptr = ptr + i - 1;
 266                 operand = (1 << 7);
 267         } else {
 268                 ptr = ptr + i;
 269                 operand = (1 << (remainder - 1));
 270         }
 271         status = *ptr & operand;
 272         if (status)
 273                 return -1;
 274
 275         *ptr = *ptr | operand;
 276
 277         return 0;
 278 }
 279
 280 void ext4fs_reset_inode_bmap(int inode_no, unsigned char *buffer, int index)
 281 {
 282         int i, remainder, status;
 283         unsigned char *ptr = buffer;
 284         unsigned char operand;
 285
 286         inode_no -= (index * ext4fs_root->sblock.inodes_per_group);
 287         i = inode_no / 8;
 288         remainder = inode_no % 8;
 289         if (remainder == 0) {
 290                 ptr = ptr + i - 1;
 291                 operand = (1 << 7);
 292         } else {
 293                 ptr = ptr + i;
 294                 operand = (1 << (remainder - 1));
 295         }
 296         status = *ptr & operand;
 297         if (status)
 298                 *ptr = *ptr & ~(operand);
 299 }
 300
 301 int ext4fs_checksum_update(unsigned int i)
 302 {
 303         struct ext2_block_group *desc;
 304         struct ext_filesystem *fs = get_fs();
 305         __u16 crc = 0;
 306
 307         desc = (struct ext2_block_group *)&fs->bgd[i];
 308         if (fs->sb->feature_ro_compat & EXT4_FEATURE_RO_COMPAT_GDT_CSUM) {
 309                 int offset = offsetof(struct ext2_block_group, bg_checksum);
 310
 311                 crc = ext2fs_crc16(~0, fs->sb->unique_id,
 312                                    sizeof(fs->sb->unique_id));
 313                 crc = ext2fs_crc16(crc, &i, sizeof(i));
 314                 crc = ext2fs_crc16(crc, desc, offset);
 315                 offset += sizeof(desc->bg_checksum);    /* skip checksum */
 316                 assert(offset == sizeof(*desc));
 317         }
 318
 319         return crc;
 320 }
 321
 322 static int check_void_in_dentry(struct ext2_dirent *dir, char *filename)
 323 {
 324         int dentry_length;
 325         int sizeof_void_space;
 326         int new_entry_byte_reqd;
 327         short padding_factor = 0;
 328
 329         if (dir->namelen % 4 != 0)
 330                 padding_factor = 4 - (dir->namelen % 4);
 331
 332         dentry_length = sizeof(struct ext2_dirent) +
 333                         dir->namelen + padding_factor;
 334         sizeof_void_space = dir->direntlen - dentry_length;
 335         if (sizeof_void_space == 0)
 336                 return 0;
 337
 338         padding_factor = 0;
 339         if (strlen(filename) % 4 != 0)
 340                 padding_factor = 4 - (strlen(filename) % 4);
 341
 342         new_entry_byte_reqd = strlen(filename) +
 343             sizeof(struct ext2_dirent) + padding_factor;
 344         if (sizeof_void_space >= new_entry_byte_reqd) {
 345                 dir->direntlen = dentry_length;
 346                 return sizeof_void_space;
 347         }
 348
 349         return 0;
 350 }
 351
 352 void ext4fs_update_parent_dentry(char *filename, int *p_ino, int file_type)
 353 {
 354         unsigned int *zero_buffer = NULL;
 355         char *root_first_block_buffer = NULL;
 356         int direct_blk_idx;
 357         long int root_blknr;
 358         long int first_block_no_of_root = 0;
 359         long int previous_blknr = -1;
 360         int totalbytes = 0;
 361         short int padding_factor = 0;
 362         unsigned int new_entry_byte_reqd;
 363         unsigned int last_entry_dirlen;
 364         int sizeof_void_space = 0;
 365         int templength = 0;
 366         int inodeno;
 367         int status;
 368         struct ext_filesystem *fs = get_fs();
 369         /* directory entry */
 370         struct ext2_dirent *dir;
 371         char *temp_dir = NULL;
 372
 373         zero_buffer = zalloc(fs->blksz);
 374         if (!zero_buffer) {
 375                 printf("No Memory\n");
 376                 return;
 377         }
 378         root_first_block_buffer = zalloc(fs->blksz);
 379         if (!root_first_block_buffer) {
 380                 free(zero_buffer);
 381                 printf("No Memory\n");
 382                 return;
 383         }
 384 restart:
 385
 386         /* read the block no allocated to a file */
 387         for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS;
 388              direct_blk_idx++) {
 389                 root_blknr = read_allocated_block(g_parent_inode,
 390                                                   direct_blk_idx);
 391                 if (root_blknr == 0) {
 392                         first_block_no_of_root = previous_blknr;
 393                         break;
 394                 }
 395                 previous_blknr = root_blknr;
 396         }
 397
 398         status = ext4fs_devread((lbaint_t)first_block_no_of_root
 399                                 * fs->sect_perblk,
 400                                 0, fs->blksz, root_first_block_buffer);
 401         if (status == 0)
 402                 goto fail;
 403
 404         if (ext4fs_log_journal(root_first_block_buffer, first_block_no_of_root))
 405                 goto fail;
 406         dir = (struct ext2_dirent *)root_first_block_buffer;
 407         totalbytes = 0;
 408         while (dir->direntlen > 0) {
 409                 /*
 410                  * blocksize-totalbytes because last directory length
 411                  * i.e. dir->direntlen is free availble space in the
 412                  * block that means  it is a last entry of directory
 413                  * entry
 414                  */
 415
 416                 /* traversing the each directory entry */
 417                 if (fs->blksz - totalbytes == dir->direntlen) {
 418                         if (strlen(filename) % 4 != 0)
 419                                 padding_factor = 4 - (strlen(filename) % 4);
 420
 421                         new_entry_byte_reqd = strlen(filename) +
 422                             sizeof(struct ext2_dirent) + padding_factor;
 423                         padding_factor = 0;
 424                         /*
 425                          * update last directory entry length to its
 426                          * length because we are creating new directory
 427                          * entry
 428                          */
 429                         if (dir->namelen % 4 != 0)
 430                                 padding_factor = 4 - (dir->namelen % 4);
 431
 432                         last_entry_dirlen = dir->namelen +
 433                             sizeof(struct ext2_dirent) + padding_factor;
 434                         if ((fs->blksz - totalbytes - last_entry_dirlen) <
 435                                 new_entry_byte_reqd) {
 436                                 printf("1st Block Full:Allocate new block\n");
 437
 438                                 if (direct_blk_idx == INDIRECT_BLOCKS - 1) {
 439                                         printf("Directory exceeds limit\n");
 440                                         goto fail;
 441                                 }
 442                                 g_parent_inode->b.blocks.dir_blocks
 443                                     [direct_blk_idx] = ext4fs_get_new_blk_no();
 444                                 if (g_parent_inode->b.blocks.dir_blocks
 445                                         [direct_blk_idx] == -1) {
 446                                         printf("no block left to assign\n");
 447                                         goto fail;
 448                                 }
 449                                 put_ext4(((uint64_t)
 450                                           ((uint64_t)g_parent_inode->b.
 451                                            blocks.dir_blocks[direct_blk_idx] *
 452                                            (uint64_t)fs->blksz)), zero_buffer, fs->blksz);
 453                                 g_parent_inode->size =
 454                                     g_parent_inode->size + fs->blksz;
 455                                 g_parent_inode->blockcnt =
 456                                     g_parent_inode->blockcnt + fs->sect_perblk;
 457                                 if (ext4fs_put_metadata
 458                                     (root_first_block_buffer,
 459                                      first_block_no_of_root))
 460                                         goto fail;
 461                                 goto restart;
 462                         }
 463                         dir->direntlen = last_entry_dirlen;
 464                         break;
 465                 }
 466
 467                 templength = dir->direntlen;
 468                 totalbytes = totalbytes + templength;
 469                 sizeof_void_space = check_void_in_dentry(dir, filename);
 470                 if (sizeof_void_space)
 471                         break;
 472
 473                 dir = (struct ext2_dirent *)((char *)dir + templength);
 474         }
 475
 476         /* make a pointer ready for creating next directory entry */
 477         templength = dir->direntlen;
 478         totalbytes = totalbytes + templength;
 479         dir = (struct ext2_dirent *)((char *)dir + templength);
 480
 481         /* get the next available inode number */
 482         inodeno = ext4fs_get_new_inode_no();
 483         if (inodeno == -1) {
 484                 printf("no inode left to assign\n");
 485                 goto fail;
 486         }
 487         dir->inode = inodeno;
 488         if (sizeof_void_space)
 489                 dir->direntlen = sizeof_void_space;
 490         else
 491                 dir->direntlen = fs->blksz - totalbytes;
 492
 493         dir->namelen = strlen(filename);
 494         dir->filetype = FILETYPE_REG;   /* regular file */
 495         temp_dir = (char *)dir;
 496         temp_dir = temp_dir + sizeof(struct ext2_dirent);
 497         memcpy(temp_dir, filename, strlen(filename));
 498
 499         *p_ino = inodeno;
 500
 501         /* update or write  the 1st block of root inode */
 502         if (ext4fs_put_metadata(root_first_block_buffer,
 503                                 first_block_no_of_root))
 504                 goto fail;
 505
 506 fail:
 507         free(zero_buffer);
 508         free(root_first_block_buffer);
 509 }
 510
 511 static int search_dir(struct ext2_inode *parent_inode, char *dirname)
 512 {
 513         int status;
 514         int inodeno;
 515         int totalbytes;
 516         int templength;
 517         int direct_blk_idx;
 518         long int blknr;
 519         int found = 0;
 520         char *ptr = NULL;
 521         unsigned char *block_buffer = NULL;
 522         struct ext2_dirent *dir = NULL;
 523         struct ext2_dirent *previous_dir = NULL;
 524         struct ext_filesystem *fs = get_fs();
 525
 526         /* read the block no allocated to a file */
 527         for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS;
 528                 direct_blk_idx++) {
 529                 blknr = read_allocated_block(parent_inode, direct_blk_idx);
 530                 if (blknr == 0)
 531                         goto fail;
 532
 533                 /* read the blocks of parenet inode */
 534                 block_buffer = zalloc(fs->blksz);
 535                 if (!block_buffer)
 536                         goto fail;
 537
 538                 status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk,
 539                                         0, fs->blksz, (char *)block_buffer);
 540                 if (status == 0)
 541                         goto fail;
 542
 543                 dir = (struct ext2_dirent *)block_buffer;
 544                 ptr = (char *)dir;
 545                 totalbytes = 0;
 546                 while (dir->direntlen >= 0) {
 547                         /*
 548                          * blocksize-totalbytes because last directory
 549                          * length i.e.,*dir->direntlen is free availble
 550                          * space in the block that means
 551                          * it is a last entry of directory entry
 552                          */
 553                         if (strlen(dirname) == dir->namelen) {
 554                                 if (strncmp(dirname, ptr +
 555                                         sizeof(struct ext2_dirent),
 556                                         dir->namelen) == 0) {
 557                                         previous_dir->direntlen +=
 558                                                         dir->direntlen;
 559                                         inodeno = dir->inode;
 560                                         dir->inode = 0;
 561                                         found = 1;
 562                                         break;
 563                                 }
 564                         }
 565
 566                         if (fs->blksz - totalbytes == dir->direntlen)
 567                                 break;
 568
 569                         /* traversing the each directory entry */
 570                         templength = dir->direntlen;
 571                         totalbytes = totalbytes + templength;
 572                         previous_dir = dir;
 573                         dir = (struct ext2_dirent *)((char *)dir + templength);
 574                         ptr = (char *)dir;
 575                 }
 576
 577                 if (found == 1) {
 578                         free(block_buffer);
 579                         block_buffer = NULL;
 580                         return inodeno;
 581                 }
 582
 583                 free(block_buffer);
 584                 block_buffer = NULL;
 585         }
 586
 587 fail:
 588         free(block_buffer);
 589
 590         return -1;
 591 }
 592
 593 static int find_dir_depth(char *dirname)
 594 {
 595         char *token = strtok(dirname, "/");
 596         int count = 0;
 597         while (token != NULL) {
 598                 token = strtok(NULL, "/");
 599                 count++;
 600         }
 601         return count + 1 + 1;
 602         /*
 603          * for example  for string /home/temp
 604          * depth=home(1)+temp(1)+1 extra for NULL;
 605          * so count is 4;
 606          */
 607 }
 608
 609 static int parse_path(char **arr, char *dirname)
 610 {
 611         char *token = strtok(dirname, "/");
 612         int i = 0;
 613
 614         /* add root */
 615         arr[i] = zalloc(strlen("/") + 1);
 616         if (!arr[i])
 617                 return -ENOMEM;
 618
 619         arr[i++] = "/";
 620
 621         /* add each path entry after root */
 622         while (token != NULL) {
 623                 arr[i] = zalloc(strlen(token) + 1);
 624                 if (!arr[i])
 625                         return -ENOMEM;
 626                 memcpy(arr[i++], token, strlen(token));
 627                 token = strtok(NULL, "/");
 628         }
 629         arr[i] = NULL;
 630
 631         return 0;
 632 }
 633
 634 int ext4fs_iget(int inode_no, struct ext2_inode *inode)
 635 {
 636         if (ext4fs_read_inode(ext4fs_root, inode_no, inode) == 0)
 637                 return -1;
 638
 639         return 0;
 640 }
 641
 642 /*
 643  * Function: ext4fs_get_parent_inode_num
 644  * Return Value: inode Number of the parent directory of  file/Directory to be
 645  * created
 646  * dirname : Input parmater, input path name of the file/directory to be created
 647  * dname : Output parameter, to be filled with the name of the directory
 648  * extracted from dirname
 649  */
 650 int ext4fs_get_parent_inode_num(const char *dirname, char *dname, int flags)
 651 {
 652         int i;
 653         int depth = 0;
 654         int matched_inode_no;
 655         int result_inode_no = -1;
 656         char **ptr = NULL;
 657         char *depth_dirname = NULL;
 658         char *parse_dirname = NULL;
 659         struct ext2_inode *parent_inode = NULL;
 660         struct ext2_inode *first_inode = NULL;
 661         struct ext2_inode temp_inode;
 662
 663         if (*dirname != '/') {
 664                 printf("Please supply Absolute path\n");
 665                 return -1;
 666         }
 667
 668         /* TODO: input validation make equivalent to linux */
 669         depth_dirname = zalloc(strlen(dirname) + 1);
 670         if (!depth_dirname)
 671                 return -ENOMEM;
 672
 673         memcpy(depth_dirname, dirname, strlen(dirname));
 674         depth = find_dir_depth(depth_dirname);
 675         parse_dirname = zalloc(strlen(dirname) + 1);
 676         if (!parse_dirname)
 677                 goto fail;
 678         memcpy(parse_dirname, dirname, strlen(dirname));
 679
 680         /* allocate memory for each directory level */
 681         ptr = zalloc((depth) * sizeof(char *));
 682         if (!ptr)
 683                 goto fail;
 684         if (parse_path(ptr, parse_dirname))
 685                 goto fail;
 686         parent_inode = zalloc(sizeof(struct ext2_inode));
 687         if (!parent_inode)
 688                 goto fail;
 689         first_inode = zalloc(sizeof(struct ext2_inode));
 690         if (!first_inode)
 691                 goto fail;
 692         memcpy(parent_inode, ext4fs_root->inode, sizeof(struct ext2_inode));
 693         memcpy(first_inode, parent_inode, sizeof(struct ext2_inode));
 694         if (flags & F_FILE)
 695                 result_inode_no = EXT2_ROOT_INO;
 696         for (i = 1; i < depth; i++) {
 697                 matched_inode_no = search_dir(parent_inode, ptr[i]);
 698                 if (matched_inode_no == -1) {
 699                         if (ptr[i + 1] == NULL && i == 1) {
 700                                 result_inode_no = EXT2_ROOT_INO;
 701                                 goto end;
 702                         } else {
 703                                 if (ptr[i + 1] == NULL)
 704                                         break;
 705                                 printf("Invalid path\n");
 706                                 result_inode_no = -1;
 707                                 goto fail;
 708                         }
 709                 } else {
 710                         if (ptr[i + 1] != NULL) {
 711                                 memset(parent_inode, '\0',
 712                                        sizeof(struct ext2_inode));
 713                                 if (ext4fs_iget(matched_inode_no,
 714                                                 parent_inode)) {
 715                                         result_inode_no = -1;
 716                                         goto fail;
 717                                 }
 718                                 result_inode_no = matched_inode_no;
 719                         } else {
 720                                 break;
 721                         }
 722                 }
 723         }
 724
 725 end:
 726         if (i == 1)
 727                 matched_inode_no = search_dir(first_inode, ptr[i]);
 728         else
 729                 matched_inode_no = search_dir(parent_inode, ptr[i]);
 730
 731         if (matched_inode_no != -1) {
 732                 ext4fs_iget(matched_inode_no, &temp_inode);
 733                 if (temp_inode.mode & S_IFDIR) {
 734                         printf("It is a Directory\n");
 735                         result_inode_no = -1;
 736                         goto fail;
 737                 }
 738         }
 739
 740         if (strlen(ptr[i]) > 256) {
 741                 result_inode_no = -1;
 742                 goto fail;
 743         }
 744         memcpy(dname, ptr[i], strlen(ptr[i]));
 745
 746 fail:
 747         free(depth_dirname);
 748         free(parse_dirname);
 749         free(ptr);
 750         free(parent_inode);
 751         free(first_inode);
 752
 753         return result_inode_no;
 754 }
 755
 756 static int check_filename(char *filename, unsigned int blknr)
 757 {
 758         unsigned int first_block_no_of_root;
 759         int totalbytes = 0;
 760         int templength = 0;
 761         int status, inodeno;
 762         int found = 0;
 763         char *root_first_block_buffer = NULL;
 764         char *root_first_block_addr = NULL;
 765         struct ext2_dirent *dir = NULL;
 766         struct ext2_dirent *previous_dir = NULL;
 767         char *ptr = NULL;
 768         struct ext_filesystem *fs = get_fs();
 769
 770         /* get the first block of root */
 771         first_block_no_of_root = blknr;
 772         root_first_block_buffer = zalloc(fs->blksz);
 773         if (!root_first_block_buffer)
 774                 return -ENOMEM;
 775         root_first_block_addr = root_first_block_buffer;
 776         status = ext4fs_devread((lbaint_t)first_block_no_of_root *
 777                                 fs->sect_perblk, 0,
 778                                 fs->blksz, root_first_block_buffer);
 779         if (status == 0)
 780                 goto fail;
 781
 782         if (ext4fs_log_journal(root_first_block_buffer, first_block_no_of_root))
 783                 goto fail;
 784         dir = (struct ext2_dirent *)root_first_block_buffer;
 785         ptr = (char *)dir;
 786         totalbytes = 0;
 787         while (dir->direntlen >= 0) {
 788                 /*
 789                  * blocksize-totalbytes because last
 790                  * directory length i.e., *dir->direntlen
 791                  * is free availble space in the block that
 792                  * means it is a last entry of directory entry
 793                  */
 794                 if (strlen(filename) == dir->namelen) {
 795                         if (strncmp(filename, ptr + sizeof(struct ext2_dirent),
 796                                 dir->namelen) == 0) {
 797                                 printf("file found deleting\n");
 798                                 previous_dir->direntlen += dir->direntlen;
 799                                 inodeno = dir->inode;
 800                                 dir->inode = 0;
 801                                 found = 1;
 802                                 break;
 803                         }
 804                 }
 805
 806                 if (fs->blksz - totalbytes == dir->direntlen)
 807                         break;
 808
 809                 /* traversing the each directory entry */
 810                 templength = dir->direntlen;
 811                 totalbytes = totalbytes + templength;
 812                 previous_dir = dir;
 813                 dir = (struct ext2_dirent *)((char *)dir + templength);
 814                 ptr = (char *)dir;
 815         }
 816
 817
 818         if (found == 1) {
 819                 if (ext4fs_put_metadata(root_first_block_addr,
 820                                         first_block_no_of_root))
 821                         goto fail;
 822                 return inodeno;
 823         }
 824 fail:
 825         free(root_first_block_buffer);
 826
 827         return -1;
 828 }
 829
 830 int ext4fs_filename_check(char *filename)
 831 {
 832         short direct_blk_idx = 0;
 833         long int blknr = -1;
 834         int inodeno = -1;
 835
 836         /* read the block no allocated to a file */
 837         for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS;
 838                 direct_blk_idx++) {
 839                 blknr = read_allocated_block(g_parent_inode, direct_blk_idx);
 840                 if (blknr == 0)
 841                         break;
 842                 inodeno = check_filename(filename, blknr);
 843                 if (inodeno != -1)
 844                         return inodeno;
 845         }
 846
 847         return -1;
 848 }
 849
 850 long int ext4fs_get_new_blk_no(void)
 851 {
 852         short i;
 853         short status;
 854         int remainder;
 855         unsigned int bg_idx;
 856         static int prev_bg_bitmap_index = -1;
 857         unsigned int blk_per_grp = ext4fs_root->sblock.blocks_per_group;
 858         struct ext_filesystem *fs = get_fs();
 859         char *journal_buffer = zalloc(fs->blksz);
 860         char *zero_buffer = zalloc(fs->blksz);
 861         if (!journal_buffer || !zero_buffer)
 862                 goto fail;
 863         struct ext2_block_group *bgd = (struct ext2_block_group *)fs->gdtable;
 864
 865         if (fs->first_pass_bbmap == 0) {
 866                 for (i = 0; i < fs->no_blkgrp; i++) {
 867                         if (bgd[i].free_blocks) {
 868                                 if (bgd[i].bg_flags & EXT4_BG_BLOCK_UNINIT) {
 869                                         put_ext4(((uint64_t) ((uint64_t)bgd[i].block_id *
 870                                                               (uint64_t)fs->blksz)),
 871                                                  zero_buffer, fs->blksz);
 872                                         bgd[i].bg_flags =
 873                                             bgd[i].
 874                                             bg_flags & ~EXT4_BG_BLOCK_UNINIT;
 875                                         memcpy(fs->blk_bmaps[i], zero_buffer,
 876                                                fs->blksz);
 877                                 }
 878                                 fs->curr_blkno =
 879                                     _get_new_blk_no(fs->blk_bmaps[i]);
 880                                 if (fs->curr_blkno == -1)
 881                                         /* if block bitmap is completely fill */
 882                                         continue;
 883                                 fs->curr_blkno = fs->curr_blkno +
 884                                                 (i * fs->blksz * 8);
 885                                 fs->first_pass_bbmap++;
 886                                 bgd[i].free_blocks--;
 887                                 fs->sb->free_blocks--;
 888                                 status = ext4fs_devread((lbaint_t)
 889                                                         bgd[i].block_id *
 890                                                         fs->sect_perblk, 0,
 891                                                         fs->blksz,
 892                                                         journal_buffer);
 893                                 if (status == 0)
 894                                         goto fail;
 895                                 if (ext4fs_log_journal(journal_buffer,
 896                                                         bgd[i].block_id))
 897                                         goto fail;
 898                                 goto success;
 899                         } else {
 900                                 debug("no space left on block group %d\n", i);
 901                         }
 902                 }
 903
 904                 goto fail;
 905         } else {
 906 restart:
 907                 fs->curr_blkno++;
 908                 /* get the blockbitmap index respective to blockno */
 909                 bg_idx = fs->curr_blkno / blk_per_grp;
 910                 if (fs->blksz == 1024) {
 911                         remainder = fs->curr_blkno % blk_per_grp;
 912                         if (!remainder)
 913                                 bg_idx--;
 914                 }
 915
 916                 /*
 917                  * To skip completely filled block group bitmaps
 918                  * Optimize the block allocation
 919                  */
 920                 if (bg_idx >= fs->no_blkgrp)
 921                         goto fail;
 922
 923                 if (bgd[bg_idx].free_blocks == 0) {
 924                         debug("block group %u is full. Skipping\n", bg_idx);
 925                         fs->curr_blkno = fs->curr_blkno + blk_per_grp;
 926                         fs->curr_blkno--;
 927                         goto restart;
 928                 }
 929
 930                 if (bgd[bg_idx].bg_flags & EXT4_BG_BLOCK_UNINIT) {
 931                         memset(zero_buffer, '\0', fs->blksz);
 932                         put_ext4(((uint64_t) ((uint64_t)bgd[bg_idx].block_id *
 933                                         (uint64_t)fs->blksz)), zero_buffer, fs->blksz);
 934                         memcpy(fs->blk_bmaps[bg_idx], zero_buffer, fs->blksz);
 935                         bgd[bg_idx].bg_flags = bgd[bg_idx].bg_flags &
 936                                                 ~EXT4_BG_BLOCK_UNINIT;
 937                 }
 938
 939                 if (ext4fs_set_block_bmap(fs->curr_blkno, fs->blk_bmaps[bg_idx],
 940                                    bg_idx) != 0) {
 941                         debug("going for restart for the block no %ld %u\n",
 942                               fs->curr_blkno, bg_idx);
 943                         goto restart;
 944                 }
 945
 946                 /* journal backup */
 947                 if (prev_bg_bitmap_index != bg_idx) {
 948                         memset(journal_buffer, '\0', fs->blksz);
 949                         status = ext4fs_devread((lbaint_t)bgd[bg_idx].block_id
 950                                                 * fs->sect_perblk,
 951                                                 0, fs->blksz, journal_buffer);
 952                         if (status == 0)
 953                                 goto fail;
 954                         if (ext4fs_log_journal(journal_buffer,
 955                                                 bgd[bg_idx].block_id))
 956                                 goto fail;
 957
 958                         prev_bg_bitmap_index = bg_idx;
 959                 }
 960                 bgd[bg_idx].free_blocks--;
 961                 fs->sb->free_blocks--;
 962                 goto success;
 963         }
 964 success:
 965         free(journal_buffer);
 966         free(zero_buffer);
 967
 968         return fs->curr_blkno;
 969 fail:
 970         free(journal_buffer);
 971         free(zero_buffer);
 972
 973         return -1;
 974 }
 975
 976 int ext4fs_get_new_inode_no(void)
 977 {
 978         short i;
 979         short status;
 980         unsigned int ibmap_idx;
 981         static int prev_inode_bitmap_index = -1;
 982         unsigned int inodes_per_grp = ext4fs_root->sblock.inodes_per_group;
 983         struct ext_filesystem *fs = get_fs();
 984         char *journal_buffer = zalloc(fs->blksz);
 985         char *zero_buffer = zalloc(fs->blksz);
 986         if (!journal_buffer || !zero_buffer)
 987                 goto fail;
 988         struct ext2_block_group *bgd = (struct ext2_block_group *)fs->gdtable;
 989
 990         if (fs->first_pass_ibmap == 0) {
 991                 for (i = 0; i < fs->no_blkgrp; i++) {
 992                         if (bgd[i].free_inodes) {
 993                                 if (bgd[i].bg_itable_unused !=
 994                                                 bgd[i].free_inodes)
 995                                         bgd[i].bg_itable_unused =
 996                                                 bgd[i].free_inodes;
 997                                 if (bgd[i].bg_flags & EXT4_BG_INODE_UNINIT) {
 998                                         put_ext4(((uint64_t)
 999                                                   ((uint64_t)bgd[i].inode_id *
1000                                                         (uint64_t)fs->blksz)),
1001                                                  zero_buffer, fs->blksz);
1002                                         bgd[i].bg_flags = bgd[i].bg_flags &
1003                                                         ~EXT4_BG_INODE_UNINIT;
1004                                         memcpy(fs->inode_bmaps[i],
1005                                                zero_buffer, fs->blksz);
1006                                 }
1007                                 fs->curr_inode_no =
1008                                     _get_new_inode_no(fs->inode_bmaps[i]);
1009                                 if (fs->curr_inode_no == -1)
1010                                         /* if block bitmap is completely fill */
1011                                         continue;
1012                                 fs->curr_inode_no = fs->curr_inode_no +
1013                                                         (i * inodes_per_grp);
1014                                 fs->first_pass_ibmap++;
1015                                 bgd[i].free_inodes--;
1016                                 bgd[i].bg_itable_unused--;
1017                                 fs->sb->free_inodes--;
1018                                 status = ext4fs_devread((lbaint_t)
1019                                                         bgd[i].inode_id *
1020                                                         fs->sect_perblk, 0,
1021                                                         fs->blksz,
1022                                                         journal_buffer);
1023                                 if (status == 0)
1024                                         goto fail;
1025                                 if (ext4fs_log_journal(journal_buffer,
1026                                                         bgd[i].inode_id))
1027                                         goto fail;
1028                                 goto success;
1029                         } else
1030                                 debug("no inode left on block group %d\n", i);
1031                 }
1032                 goto fail;
1033         } else {
1034 restart:
1035                 fs->curr_inode_no++;
1036                 /* get the blockbitmap index respective to blockno */
1037                 ibmap_idx = fs->curr_inode_no / inodes_per_grp;
1038                 if (bgd[ibmap_idx].bg_flags & EXT4_BG_INODE_UNINIT) {
1039                         memset(zero_buffer, '\0', fs->blksz);
1040                         put_ext4(((uint64_t) ((uint64_t)bgd[ibmap_idx].inode_id *
1041                                               (uint64_t)fs->blksz)), zero_buffer,
1042                                  fs->blksz);
1043                         bgd[ibmap_idx].bg_flags =
1044                             bgd[ibmap_idx].bg_flags & ~EXT4_BG_INODE_UNINIT;
1045                         memcpy(fs->inode_bmaps[ibmap_idx], zero_buffer,
1046                                 fs->blksz);
1047                 }
1048
1049                 if (ext4fs_set_inode_bmap(fs->curr_inode_no,
1050                                           fs->inode_bmaps[ibmap_idx],
1051                                           ibmap_idx) != 0) {
1052                         debug("going for restart for the block no %d %u\n",
1053                               fs->curr_inode_no, ibmap_idx);
1054                         goto restart;
1055                 }
1056
1057                 /* journal backup */
1058                 if (prev_inode_bitmap_index != ibmap_idx) {
1059                         memset(journal_buffer, '\0', fs->blksz);
1060                         status = ext4fs_devread((lbaint_t)
1061                                                 bgd[ibmap_idx].inode_id
1062                                                 * fs->sect_perblk,
1063                                                 0, fs->blksz, journal_buffer);
1064                         if (status == 0)
1065                                 goto fail;
1066                         if (ext4fs_log_journal(journal_buffer,
1067                                                 bgd[ibmap_idx].inode_id))
1068                                 goto fail;
1069                         prev_inode_bitmap_index = ibmap_idx;
1070                 }
1071                 if (bgd[ibmap_idx].bg_itable_unused !=
1072                                 bgd[ibmap_idx].free_inodes)
1073                         bgd[ibmap_idx].bg_itable_unused =
1074                                         bgd[ibmap_idx].free_inodes;
1075                 bgd[ibmap_idx].free_inodes--;
1076                 bgd[ibmap_idx].bg_itable_unused--;
1077                 fs->sb->free_inodes--;
1078                 goto success;
1079         }
1080
1081 success:
1082         free(journal_buffer);
1083         free(zero_buffer);
1084
1085         return fs->curr_inode_no;
1086 fail:
1087         free(journal_buffer);
1088         free(zero_buffer);
1089
1090         return -1;
1091
1092 }
1093
1094
1095 static void alloc_single_indirect_block(struct ext2_inode *file_inode,
1096                                         unsigned int *total_remaining_blocks,
1097                                         unsigned int *no_blks_reqd)
1098 {
1099         short i;
1100         short status;
1101         long int actual_block_no;
1102         long int si_blockno;
1103         /* si :single indirect */
1104         unsigned int *si_buffer = NULL;
1105         unsigned int *si_start_addr = NULL;
1106         struct ext_filesystem *fs = get_fs();
1107
1108         if (*total_remaining_blocks != 0) {
1109                 si_buffer = zalloc(fs->blksz);
1110                 if (!si_buffer) {
1111                         printf("No Memory\n");
1112                         return;
1113                 }
1114                 si_start_addr = si_buffer;
1115                 si_blockno = ext4fs_get_new_blk_no();
1116                 if (si_blockno == -1) {
1117                         printf("no block left to assign\n");
1118                         goto fail;
1119                 }
1120                 (*no_blks_reqd)++;
1121                 debug("SIPB %ld: %u\n", si_blockno, *total_remaining_blocks);
1122
1123                 status = ext4fs_devread((lbaint_t)si_blockno * fs->sect_perblk,
1124                                         0, fs->blksz, (char *)si_buffer);
1125                 memset(si_buffer, '\0', fs->blksz);
1126                 if (status == 0)
1127                         goto fail;
1128
1129                 for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
1130                         actual_block_no = ext4fs_get_new_blk_no();
1131                         if (actual_block_no == -1) {
1132                                 printf("no block left to assign\n");
1133                                 goto fail;
1134                         }
1135                         *si_buffer = actual_block_no;
1136                         debug("SIAB %u: %u\n", *si_buffer,
1137                                 *total_remaining_blocks);
1138
1139                         si_buffer++;
1140                         (*total_remaining_blocks)--;
1141                         if (*total_remaining_blocks == 0)
1142                                 break;
1143                 }
1144
1145                 /* write the block to disk */
1146                 put_ext4(((uint64_t) ((uint64_t)si_blockno * (uint64_t)fs->blksz)),
1147                          si_start_addr, fs->blksz);
1148                 file_inode->b.blocks.indir_block = si_blockno;
1149         }
1150 fail:
1151         free(si_start_addr);
1152 }
1153
1154 static void alloc_double_indirect_block(struct ext2_inode *file_inode,
1155                                         unsigned int *total_remaining_blocks,
1156                                         unsigned int *no_blks_reqd)
1157 {
1158         short i;
1159         short j;
1160         short status;
1161         long int actual_block_no;
1162         /* di:double indirect */
1163         long int di_blockno_parent;
1164         long int di_blockno_child;
1165         unsigned int *di_parent_buffer = NULL;
1166         unsigned int *di_child_buff = NULL;
1167         unsigned int *di_block_start_addr = NULL;
1168         unsigned int *di_child_buff_start = NULL;
1169         struct ext_filesystem *fs = get_fs();
1170
1171         if (*total_remaining_blocks != 0) {
1172                 /* double indirect parent block connecting to inode */
1173                 di_blockno_parent = ext4fs_get_new_blk_no();
1174                 if (di_blockno_parent == -1) {
1175                         printf("no block left to assign\n");
1176                         goto fail;
1177                 }
1178                 di_parent_buffer = zalloc(fs->blksz);
1179                 if (!di_parent_buffer)
1180                         goto fail;
1181
1182                 di_block_start_addr = di_parent_buffer;
1183                 (*no_blks_reqd)++;
1184                 debug("DIPB %ld: %u\n", di_blockno_parent,
1185                       *total_remaining_blocks);
1186
1187                 status = ext4fs_devread((lbaint_t)di_blockno_parent *
1188                                         fs->sect_perblk, 0,
1189                                         fs->blksz, (char *)di_parent_buffer);
1190
1191                 if (!status) {
1192                         printf("%s: Device read error!\n", __func__);
1193                         goto fail;
1194                 }
1195                 memset(di_parent_buffer, '\0', fs->blksz);
1196
1197                 /*
1198                  * start:for each double indirect parent
1199                  * block create one more block
1200                  */
1201                 for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
1202                         di_blockno_child = ext4fs_get_new_blk_no();
1203                         if (di_blockno_child == -1) {
1204                                 printf("no block left to assign\n");
1205                                 goto fail;
1206                         }
1207                         di_child_buff = zalloc(fs->blksz);
1208                         if (!di_child_buff)
1209                                 goto fail;
1210
1211                         di_child_buff_start = di_child_buff;
1212                         *di_parent_buffer = di_blockno_child;
1213                         di_parent_buffer++;
1214                         (*no_blks_reqd)++;
1215                         debug("DICB %ld: %u\n", di_blockno_child,
1216                               *total_remaining_blocks);
1217
1218                         status = ext4fs_devread((lbaint_t)di_blockno_child *
1219                                                 fs->sect_perblk, 0,
1220                                                 fs->blksz,
1221                                                 (char *)di_child_buff);
1222
1223                         if (!status) {
1224                                 printf("%s: Device read error!\n", __func__);
1225                                 goto fail;
1226                         }
1227                         memset(di_child_buff, '\0', fs->blksz);
1228                         /* filling of actual datablocks for each child */
1229                         for (j = 0; j < (fs->blksz / sizeof(int)); j++) {
1230                                 actual_block_no = ext4fs_get_new_blk_no();
1231                                 if (actual_block_no == -1) {
1232                                         printf("no block left to assign\n");
1233                                         goto fail;
1234                                 }
1235                                 *di_child_buff = actual_block_no;
1236                                 debug("DIAB %ld: %u\n", actual_block_no,
1237                                       *total_remaining_blocks);
1238
1239                                 di_child_buff++;
1240                                 (*total_remaining_blocks)--;
1241                                 if (*total_remaining_blocks == 0)
1242                                         break;
1243                         }
1244                         /* write the block  table */
1245                         put_ext4(((uint64_t) ((uint64_t)di_blockno_child * (uint64_t)fs->blksz)),
1246                                  di_child_buff_start, fs->blksz);
1247                         free(di_child_buff_start);
1248                         di_child_buff_start = NULL;
1249
1250                         if (*total_remaining_blocks == 0)
1251                                 break;
1252                 }
1253                 put_ext4(((uint64_t) ((uint64_t)di_blockno_parent * (uint64_t)fs->blksz)),
1254                          di_block_start_addr, fs->blksz);
1255                 file_inode->b.blocks.double_indir_block = di_blockno_parent;
1256         }
1257 fail:
1258         free(di_block_start_addr);
1259 }
1260
1261 static void alloc_triple_indirect_block(struct ext2_inode *file_inode,
1262                                         unsigned int *total_remaining_blocks,
1263                                         unsigned int *no_blks_reqd)
1264 {
1265         short i;
1266         short j;
1267         short k;
1268         long int actual_block_no;
1269         /* ti: Triple Indirect */
1270         long int ti_gp_blockno;
1271         long int ti_parent_blockno;
1272         long int ti_child_blockno;
1273         unsigned int *ti_gp_buff = NULL;
1274         unsigned int *ti_parent_buff = NULL;
1275         unsigned int *ti_child_buff = NULL;
1276         unsigned int *ti_gp_buff_start_addr = NULL;
1277         unsigned int *ti_pbuff_start_addr = NULL;
1278         unsigned int *ti_cbuff_start_addr = NULL;
1279         struct ext_filesystem *fs = get_fs();
1280         if (*total_remaining_blocks != 0) {
1281                 /* triple indirect grand parent block connecting to inode */
1282                 ti_gp_blockno = ext4fs_get_new_blk_no();
1283                 if (ti_gp_blockno == -1) {
1284                         printf("no block left to assign\n");
1285                         goto fail;
1286                 }
1287                 ti_gp_buff = zalloc(fs->blksz);
1288                 if (!ti_gp_buff)
1289                         goto fail;
1290
1291                 ti_gp_buff_start_addr = ti_gp_buff;
1292                 (*no_blks_reqd)++;
1293                 debug("TIGPB %ld: %u\n", ti_gp_blockno,
1294                       *total_remaining_blocks);
1295
1296                 /* for each 4 byte grand parent entry create one more block */
1297                 for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
1298                         ti_parent_blockno = ext4fs_get_new_blk_no();
1299                         if (ti_parent_blockno == -1) {
1300                                 printf("no block left to assign\n");
1301                                 goto fail;
1302                         }
1303                         ti_parent_buff = zalloc(fs->blksz);
1304                         if (!ti_parent_buff)
1305                                 goto fail;
1306
1307                         ti_pbuff_start_addr = ti_parent_buff;
1308                         *ti_gp_buff = ti_parent_blockno;
1309                         ti_gp_buff++;
1310                         (*no_blks_reqd)++;
1311                         debug("TIPB %ld: %u\n", ti_parent_blockno,
1312                               *total_remaining_blocks);
1313
1314                         /* for each 4 byte entry parent create one more block */
1315                         for (j = 0; j < (fs->blksz / sizeof(int)); j++) {
1316                                 ti_child_blockno = ext4fs_get_new_blk_no();
1317                                 if (ti_child_blockno == -1) {
1318                                         printf("no block left assign\n");
1319                                         goto fail;
1320                                 }
1321                                 ti_child_buff = zalloc(fs->blksz);
1322                                 if (!ti_child_buff)
1323                                         goto fail;
1324
1325                                 ti_cbuff_start_addr = ti_child_buff;
1326                                 *ti_parent_buff = ti_child_blockno;
1327                                 ti_parent_buff++;
1328                                 (*no_blks_reqd)++;
1329                                 debug("TICB %ld: %u\n", ti_parent_blockno,
1330                                       *total_remaining_blocks);
1331
1332                                 /* fill actual datablocks for each child */
1333                                 for (k = 0; k < (fs->blksz / sizeof(int));
1334                                         k++) {
1335                                         actual_block_no =
1336                                             ext4fs_get_new_blk_no();
1337                                         if (actual_block_no == -1) {
1338                                                 printf("no block left\n");
1339                                                 goto fail;
1340                                         }
1341                                         *ti_child_buff = actual_block_no;
1342                                         debug("TIAB %ld: %u\n", actual_block_no,
1343                                               *total_remaining_blocks);
1344
1345                                         ti_child_buff++;
1346                                         (*total_remaining_blocks)--;
1347                                         if (*total_remaining_blocks == 0)
1348                                                 break;
1349                                 }
1350                                 /* write the child block */
1351                                 put_ext4(((uint64_t) ((uint64_t)ti_child_blockno *
1352                                                       (uint64_t)fs->blksz)),
1353                                          ti_cbuff_start_addr, fs->blksz);
1354                                 free(ti_cbuff_start_addr);
1355
1356                                 if (*total_remaining_blocks == 0)
1357                                         break;
1358                         }
1359                         /* write the parent block */
1360                         put_ext4(((uint64_t) ((uint64_t)ti_parent_blockno * (uint64_t)fs->blksz)),
1361                                  ti_pbuff_start_addr, fs->blksz);
1362                         free(ti_pbuff_start_addr);
1363
1364                         if (*total_remaining_blocks == 0)
1365                                 break;
1366                 }
1367                 /* write the grand parent block */
1368                 put_ext4(((uint64_t) ((uint64_t)ti_gp_blockno * (uint64_t)fs->blksz)),
1369                          ti_gp_buff_start_addr, fs->blksz);
1370                 file_inode->b.blocks.triple_indir_block = ti_gp_blockno;
1371         }
1372 fail:
1373         free(ti_gp_buff_start_addr);
1374 }
1375
1376 void ext4fs_allocate_blocks(struct ext2_inode *file_inode,
1377                                 unsigned int total_remaining_blocks,
1378                                 unsigned int *total_no_of_block)
1379 {
1380         short i;
1381         long int direct_blockno;
1382         unsigned int no_blks_reqd = 0;
1383
1384         /* allocation of direct blocks */
1385         for (i = 0; total_remaining_blocks && i < INDIRECT_BLOCKS; i++) {
1386                 direct_blockno = ext4fs_get_new_blk_no();
1387                 if (direct_blockno == -1) {
1388                         printf("no block left to assign\n");
1389                         return;
1390                 }
1391                 file_inode->b.blocks.dir_blocks[i] = direct_blockno;
1392                 debug("DB %ld: %u\n", direct_blockno, total_remaining_blocks);
1393
1394                 total_remaining_blocks--;
1395         }
1396
1397         alloc_single_indirect_block(file_inode, &total_remaining_blocks,
1398                                     &no_blks_reqd);
1399         alloc_double_indirect_block(file_inode, &total_remaining_blocks,
1400                                     &no_blks_reqd);
1401         alloc_triple_indirect_block(file_inode, &total_remaining_blocks,
1402                                     &no_blks_reqd);
1403         *total_no_of_block += no_blks_reqd;
1404 }
1405
1406 #endif
1407
1408 static struct ext4_extent_header *ext4fs_get_extent_block
1409         (struct ext2_data *data, char *buf,
1410                 struct ext4_extent_header *ext_block,
1411                 uint32_t fileblock, int log2_blksz)
1412 {
1413         struct ext4_extent_idx *index;
1414         unsigned long long block;
1415         int blksz = EXT2_BLOCK_SIZE(data);
1416         int i;
1417
1418         while (1) {
1419                 index = (struct ext4_extent_idx *)(ext_block + 1);
1420
1421                 if (le16_to_cpu(ext_block->eh_magic) != EXT4_EXT_MAGIC)
1422                         return 0;
1423
1424                 if (ext_block->eh_depth == 0)
1425                         return ext_block;
1426                 i = -1;
1427                 do {
1428                         i++;
1429                         if (i >= le16_to_cpu(ext_block->eh_entries))
1430                                 break;
1431                 } while (fileblock >= le32_to_cpu(index[i].ei_block));
1432
1433                 if (--i < 0)
1434                         return 0;
1435
1436                 block = le16_to_cpu(index[i].ei_leaf_hi);
1437                 block = (block << 32) + le32_to_cpu(index[i].ei_leaf_lo);
1438
1439                 if (ext4fs_devread((lbaint_t)block << log2_blksz, 0, blksz,
1440                                    buf))
1441                         ext_block = (struct ext4_extent_header *)buf;
1442                 else
1443                         return 0;
1444         }
1445 }
1446
1447 static int ext4fs_blockgroup
1448         (struct ext2_data *data, int group, struct ext2_block_group *blkgrp)
1449 {
1450         long int blkno;
1451         unsigned int blkoff, desc_per_blk;
1452         int log2blksz = get_fs()->dev_desc->log2blksz;
1453
1454         desc_per_blk = EXT2_BLOCK_SIZE(data) / sizeof(struct ext2_block_group);
1455
1456         blkno = __le32_to_cpu(data->sblock.first_data_block) + 1 +
1457                         group / desc_per_blk;
1458         blkoff = (group % desc_per_blk) * sizeof(struct ext2_block_group);
1459
1460         debug("ext4fs read %d group descriptor (blkno %ld blkoff %u)\n",
1461               group, blkno, blkoff);
1462
1463         return ext4fs_devread((lbaint_t)blkno <<
1464                               (LOG2_BLOCK_SIZE(data) - log2blksz),
1465                               blkoff, sizeof(struct ext2_block_group),
1466                               (char *)blkgrp);
1467 }
1468
1469 int ext4fs_read_inode(struct ext2_data *data, int ino, struct ext2_inode *inode)
1470 {
1471         struct ext2_block_group blkgrp;
1472         struct ext2_sblock *sblock = &data->sblock;
1473         struct ext_filesystem *fs = get_fs();
1474         int log2blksz = get_fs()->dev_desc->log2blksz;
1475         int inodes_per_block, status;
1476         long int blkno;
1477         unsigned int blkoff;
1478
1479         /* It is easier to calculate if the first inode is 0. */
1480         ino--;
1481         status = ext4fs_blockgroup(data, ino / __le32_to_cpu
1482                                    (sblock->inodes_per_group), &blkgrp);
1483         if (status == 0)
1484                 return 0;
1485
1486         inodes_per_block = EXT2_BLOCK_SIZE(data) / fs->inodesz;
1487         blkno = __le32_to_cpu(blkgrp.inode_table_id) +
1488             (ino % __le32_to_cpu(sblock->inodes_per_group)) / inodes_per_block;
1489         blkoff = (ino % inodes_per_block) * fs->inodesz;
1490         /* Read the inode. */
1491         status = ext4fs_devread((lbaint_t)blkno << (LOG2_BLOCK_SIZE(data) -
1492                                 log2blksz), blkoff,
1493                                 sizeof(struct ext2_inode), (char *)inode);
1494         if (status == 0)
1495                 return 0;
1496
1497         return 1;
1498 }
1499
1500 long int read_allocated_block(struct ext2_inode *inode, int fileblock)
1501 {
1502         long int blknr;
1503         int blksz;
1504         int log2_blksz;
1505         int status;
1506         long int rblock;
1507         long int perblock_parent;
1508         long int perblock_child;
1509         unsigned long long start;
1510         /* get the blocksize of the filesystem */
1511         blksz = EXT2_BLOCK_SIZE(ext4fs_root);
1512         log2_blksz = LOG2_BLOCK_SIZE(ext4fs_root)
1513                 - get_fs()->dev_desc->log2blksz;
1514
1515         if (le32_to_cpu(inode->flags) & EXT4_EXTENTS_FL) {
1516                 char *buf = zalloc(blksz);
1517                 if (!buf)
1518                         return -ENOMEM;
1519                 struct ext4_extent_header *ext_block;
1520                 struct ext4_extent *extent;
1521                 int i = -1;
1522                 ext_block =
1523                         ext4fs_get_extent_block(ext4fs_root, buf,
1524                                                 (struct ext4_extent_header *)
1525                                                 inode->b.blocks.dir_blocks,
1526                                                 fileblock, log2_blksz);
1527                 if (!ext_block) {
1528                         printf("invalid extent block\n");
1529                         free(buf);
1530                         return -EINVAL;
1531                 }
1532
1533                 extent = (struct ext4_extent *)(ext_block + 1);
1534
1535                 do {
1536                         i++;
1537                         if (i >= le16_to_cpu(ext_block->eh_entries))
1538                                 break;
1539                 } while (fileblock >= le32_to_cpu(extent[i].ee_block));
1540                 if (--i >= 0) {
1541                         fileblock -= le32_to_cpu(extent[i].ee_block);
1542                         if (fileblock >= le16_to_cpu(extent[i].ee_len)) {
1543                                 free(buf);
1544                                 return 0;
1545                         }
1546
1547                         start = le16_to_cpu(extent[i].ee_start_hi);
1548                         start = (start << 32) +
1549                                         le32_to_cpu(extent[i].ee_start_lo);
1550                         free(buf);
1551                         return fileblock + start;
1552                 }
1553
1554                 printf("Extent Error\n");
1555                 free(buf);
1556                 return -1;
1557         }
1558
1559         /* Direct blocks. */
1560         if (fileblock < INDIRECT_BLOCKS)
1561                 blknr = __le32_to_cpu(inode->b.blocks.dir_blocks[fileblock]);
1562
1563         /* Indirect. */
1564         else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4))) {
1565                 if (ext4fs_indir1_block == NULL) {
1566                         ext4fs_indir1_block = zalloc(blksz);
1567                         if (ext4fs_indir1_block == NULL) {
1568                                 printf("** SI ext2fs read block (indir 1)"
1569                                         "malloc failed. **\n");
1570                                 return -1;
1571                         }
1572                         ext4fs_indir1_size = blksz;
1573                         ext4fs_indir1_blkno = -1;
1574                 }
1575                 if (blksz != ext4fs_indir1_size) {
1576                         free(ext4fs_indir1_block);
1577                         ext4fs_indir1_block = NULL;
1578                         ext4fs_indir1_size = 0;
1579                         ext4fs_indir1_blkno = -1;
1580                         ext4fs_indir1_block = zalloc(blksz);
1581                         if (ext4fs_indir1_block == NULL) {
1582                                 printf("** SI ext2fs read block (indir 1):"
1583                                         "malloc failed. **\n");
1584                                 return -1;
1585                         }
1586                         ext4fs_indir1_size = blksz;
1587                 }
1588                 if ((__le32_to_cpu(inode->b.blocks.indir_block) <<
1589                      log2_blksz) != ext4fs_indir1_blkno) {
1590                         status =
1591                             ext4fs_devread((lbaint_t)__le32_to_cpu
1592                                            (inode->b.blocks.
1593                                             indir_block) << log2_blksz, 0,
1594                                            blksz, (char *)ext4fs_indir1_block);
1595                         if (status == 0) {
1596                                 printf("** SI ext2fs read block (indir 1)"
1597                                         "failed. **\n");
1598                                 return 0;
1599                         }
1600                         ext4fs_indir1_blkno =
1601                                 __le32_to_cpu(inode->b.blocks.
1602                                                indir_block) << log2_blksz;
1603                 }
1604                 blknr = __le32_to_cpu(ext4fs_indir1_block
1605                                       [fileblock - INDIRECT_BLOCKS]);
1606         }
1607         /* Double indirect. */
1608         else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4 *
1609                                         (blksz / 4 + 1)))) {
1610
1611                 long int perblock = blksz / 4;
1612                 long int rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4);
1613
1614                 if (ext4fs_indir1_block == NULL) {
1615                         ext4fs_indir1_block = zalloc(blksz);
1616                         if (ext4fs_indir1_block == NULL) {
1617                                 printf("** DI ext2fs read block (indir 2 1)"
1618                                         "malloc failed. **\n");
1619                                 return -1;
1620                         }
1621                         ext4fs_indir1_size = blksz;
1622                         ext4fs_indir1_blkno = -1;
1623                 }
1624                 if (blksz != ext4fs_indir1_size) {
1625                         free(ext4fs_indir1_block);
1626                         ext4fs_indir1_block = NULL;
1627                         ext4fs_indir1_size = 0;
1628                         ext4fs_indir1_blkno = -1;
1629                         ext4fs_indir1_block = zalloc(blksz);
1630                         if (ext4fs_indir1_block == NULL) {
1631                                 printf("** DI ext2fs read block (indir 2 1)"
1632                                         "malloc failed. **\n");
1633                                 return -1;
1634                         }
1635                         ext4fs_indir1_size = blksz;
1636                 }
1637                 if ((__le32_to_cpu(inode->b.blocks.double_indir_block) <<
1638                      log2_blksz) != ext4fs_indir1_blkno) {
1639                         status =
1640                             ext4fs_devread((lbaint_t)__le32_to_cpu
1641                                            (inode->b.blocks.
1642                                             double_indir_block) << log2_blksz,
1643                                            0, blksz,
1644                                            (char *)ext4fs_indir1_block);
1645                         if (status == 0) {
1646                                 printf("** DI ext2fs read block (indir 2 1)"
1647                                         "failed. **\n");
1648                                 return -1;
1649                         }
1650                         ext4fs_indir1_blkno =
1651                             __le32_to_cpu(inode->b.blocks.double_indir_block) <<
1652                             log2_blksz;
1653                 }
1654
1655                 if (ext4fs_indir2_block == NULL) {
1656                         ext4fs_indir2_block = zalloc(blksz);
1657                         if (ext4fs_indir2_block == NULL) {
1658                                 printf("** DI ext2fs read block (indir 2 2)"
1659                                         "malloc failed. **\n");
1660                                 return -1;
1661                         }
1662                         ext4fs_indir2_size = blksz;
1663                         ext4fs_indir2_blkno = -1;
1664                 }
1665                 if (blksz != ext4fs_indir2_size) {
1666                         free(ext4fs_indir2_block);
1667                         ext4fs_indir2_block = NULL;
1668                         ext4fs_indir2_size = 0;
1669                         ext4fs_indir2_blkno = -1;
1670                         ext4fs_indir2_block = zalloc(blksz);
1671                         if (ext4fs_indir2_block == NULL) {
1672                                 printf("** DI ext2fs read block (indir 2 2)"
1673                                         "malloc failed. **\n");
1674                                 return -1;
1675                         }
1676                         ext4fs_indir2_size = blksz;
1677                 }
1678                 if ((__le32_to_cpu(ext4fs_indir1_block[rblock / perblock]) <<
1679                      log2_blksz) != ext4fs_indir2_blkno) {
1680                         status = ext4fs_devread((lbaint_t)__le32_to_cpu
1681                                                 (ext4fs_indir1_block
1682                                                  [rblock /
1683                                                   perblock]) << log2_blksz, 0,
1684                                                 blksz,
1685                                                 (char *)ext4fs_indir2_block);
1686                         if (status == 0) {
1687                                 printf("** DI ext2fs read block (indir 2 2)"
1688                                         "failed. **\n");
1689                                 return -1;
1690                         }
1691                         ext4fs_indir2_blkno =
1692                             __le32_to_cpu(ext4fs_indir1_block[rblock
1693                                                               /
1694                                                               perblock]) <<
1695                             log2_blksz;
1696                 }
1697                 blknr = __le32_to_cpu(ext4fs_indir2_block[rblock % perblock]);
1698         }
1699         /* Tripple indirect. */
1700         else {
1701                 rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4 +
1702                                       (blksz / 4 * blksz / 4));
1703                 perblock_child = blksz / 4;
1704                 perblock_parent = ((blksz / 4) * (blksz / 4));
1705
1706                 if (ext4fs_indir1_block == NULL) {
1707                         ext4fs_indir1_block = zalloc(blksz);
1708                         if (ext4fs_indir1_block == NULL) {
1709                                 printf("** TI ext2fs read block (indir 2 1)"
1710                                         "malloc failed. **\n");
1711                                 return -1;
1712                         }
1713                         ext4fs_indir1_size = blksz;
1714                         ext4fs_indir1_blkno = -1;
1715                 }
1716                 if (blksz != ext4fs_indir1_size) {
1717                         free(ext4fs_indir1_block);
1718                         ext4fs_indir1_block = NULL;
1719                         ext4fs_indir1_size = 0;
1720                         ext4fs_indir1_blkno = -1;
1721                         ext4fs_indir1_block = zalloc(blksz);
1722                         if (ext4fs_indir1_block == NULL) {
1723                                 printf("** TI ext2fs read block (indir 2 1)"
1724                                         "malloc failed. **\n");
1725                                 return -1;
1726                         }
1727                         ext4fs_indir1_size = blksz;
1728                 }
1729                 if ((__le32_to_cpu(inode->b.blocks.triple_indir_block) <<
1730                      log2_blksz) != ext4fs_indir1_blkno) {
1731                         status = ext4fs_devread
1732                             ((lbaint_t)
1733                              __le32_to_cpu(inode->b.blocks.triple_indir_block)
1734                              << log2_blksz, 0, blksz,
1735                              (char *)ext4fs_indir1_block);
1736                         if (status == 0) {
1737                                 printf("** TI ext2fs read block (indir 2 1)"
1738                                         "failed. **\n");
1739                                 return -1;
1740                         }
1741                         ext4fs_indir1_blkno =
1742                             __le32_to_cpu(inode->b.blocks.triple_indir_block) <<
1743                             log2_blksz;
1744                 }
1745
1746                 if (ext4fs_indir2_block == NULL) {
1747                         ext4fs_indir2_block = zalloc(blksz);
1748                         if (ext4fs_indir2_block == NULL) {
1749                                 printf("** TI ext2fs read block (indir 2 2)"
1750                                         "malloc failed. **\n");
1751                                 return -1;
1752                         }
1753                         ext4fs_indir2_size = blksz;
1754                         ext4fs_indir2_blkno = -1;
1755                 }
1756                 if (blksz != ext4fs_indir2_size) {
1757                         free(ext4fs_indir2_block);
1758                         ext4fs_indir2_block = NULL;
1759                         ext4fs_indir2_size = 0;
1760                         ext4fs_indir2_blkno = -1;
1761                         ext4fs_indir2_block = zalloc(blksz);
1762                         if (ext4fs_indir2_block == NULL) {
1763                                 printf("** TI ext2fs read block (indir 2 2)"
1764                                         "malloc failed. **\n");
1765                                 return -1;
1766                         }
1767                         ext4fs_indir2_size = blksz;
1768                 }
1769                 if ((__le32_to_cpu(ext4fs_indir1_block[rblock /
1770                                                        perblock_parent]) <<
1771                      log2_blksz)
1772                     != ext4fs_indir2_blkno) {
1773                         status = ext4fs_devread((lbaint_t)__le32_to_cpu
1774                                                 (ext4fs_indir1_block
1775                                                  [rblock /
1776                                                   perblock_parent]) <<
1777                                                 log2_blksz, 0, blksz,
1778                                                 (char *)ext4fs_indir2_block);
1779                         if (status == 0) {
1780                                 printf("** TI ext2fs read block (indir 2 2)"
1781                                         "failed. **\n");
1782                                 return -1;
1783                         }
1784                         ext4fs_indir2_blkno =
1785                             __le32_to_cpu(ext4fs_indir1_block[rblock /
1786                                                               perblock_parent])
1787                             << log2_blksz;
1788                 }
1789
1790                 if (ext4fs_indir3_block == NULL) {
1791                         ext4fs_indir3_block = zalloc(blksz);
1792                         if (ext4fs_indir3_block == NULL) {
1793                                 printf("** TI ext2fs read block (indir 2 2)"
1794                                         "malloc failed. **\n");
1795                                 return -1;
1796                         }
1797                         ext4fs_indir3_size = blksz;
1798                         ext4fs_indir3_blkno = -1;
1799                 }
1800                 if (blksz != ext4fs_indir3_size) {
1801                         free(ext4fs_indir3_block);
1802                         ext4fs_indir3_block = NULL;
1803                         ext4fs_indir3_size = 0;
1804                         ext4fs_indir3_blkno = -1;
1805                         ext4fs_indir3_block = zalloc(blksz);
1806                         if (ext4fs_indir3_block == NULL) {
1807                                 printf("** TI ext2fs read block (indir 2 2)"
1808                                         "malloc failed. **\n");
1809                                 return -1;
1810                         }
1811                         ext4fs_indir3_size = blksz;
1812                 }
1813                 if ((__le32_to_cpu(ext4fs_indir2_block[rblock
1814                                                        /
1815                                                        perblock_child]) <<
1816                      log2_blksz) != ext4fs_indir3_blkno) {
1817                         status =
1818                             ext4fs_devread((lbaint_t)__le32_to_cpu
1819                                            (ext4fs_indir2_block
1820                                             [(rblock / perblock_child)
1821                                              % (blksz / 4)]) << log2_blksz, 0,
1822                                            blksz, (char *)ext4fs_indir3_block);
1823                         if (status == 0) {
1824                                 printf("** TI ext2fs read block (indir 2 2)"
1825                                        "failed. **\n");
1826                                 return -1;
1827                         }
1828                         ext4fs_indir3_blkno =
1829                             __le32_to_cpu(ext4fs_indir2_block[(rblock /
1830                                                                perblock_child) %
1831                                                               (blksz /
1832                                                                4)]) <<
1833                             log2_blksz;
1834                 }
1835
1836                 blknr = __le32_to_cpu(ext4fs_indir3_block
1837                                       [rblock % perblock_child]);
1838         }
1839         debug("read_allocated_block %ld\n", blknr);
1840
1841         return blknr;
1842 }
1843
1844 /**
1845  * ext4fs_reinit_global() - Reinitialize values of ext4 write implementation's
1846  *                          global pointers
1847  *
1848  * This function assures that for a file with the same name but different size
1849  * the sequential store on the ext4 filesystem will be correct.
1850  *
1851  * In this function the global data, responsible for internal representation
1852  * of the ext4 data are initialized to the reset state. Without this, during
1853  * replacement of the smaller file with the bigger truncation of new file was
1854  * performed.
1855  */
1856 void ext4fs_reinit_global(void)
1857 {
1858         if (ext4fs_indir1_block != NULL) {
1859                 free(ext4fs_indir1_block);
1860                 ext4fs_indir1_block = NULL;
1861                 ext4fs_indir1_size = 0;
1862                 ext4fs_indir1_blkno = -1;
1863         }
1864         if (ext4fs_indir2_block != NULL) {
1865                 free(ext4fs_indir2_block);
1866                 ext4fs_indir2_block = NULL;
1867                 ext4fs_indir2_size = 0;
1868                 ext4fs_indir2_blkno = -1;
1869         }
1870         if (ext4fs_indir3_block != NULL) {
1871                 free(ext4fs_indir3_block);
1872                 ext4fs_indir3_block = NULL;
1873                 ext4fs_indir3_size = 0;
1874                 ext4fs_indir3_blkno = -1;
1875         }
1876 }
1877 void ext4fs_close(void)
1878 {
1879         if ((ext4fs_file != NULL) && (ext4fs_root != NULL)) {
1880                 ext4fs_free_node(ext4fs_file, &ext4fs_root->diropen);
1881                 ext4fs_file = NULL;
1882         }
1883         if (ext4fs_root != NULL) {
1884                 free(ext4fs_root);
1885                 ext4fs_root = NULL;
1886         }
1887
1888         ext4fs_reinit_global();
1889 }
1890
1891 int ext4fs_iterate_dir(struct ext2fs_node *dir, char *name,
1892                                 struct ext2fs_node **fnode, int *ftype)
1893 {
1894         unsigned int fpos = 0;
1895         int status;
1896         loff_t actread;
1897         struct ext2fs_node *diro = (struct ext2fs_node *) dir;
1898
1899 #ifdef DEBUG
1900         if (name != NULL)
1901                 printf("Iterate dir %s\n", name);
1902 #endif /* of DEBUG */
1903         if (!diro->inode_read) {
1904                 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode);
1905                 if (status == 0)
1906                         return 0;
1907         }
1908         /* Search the file.  */
1909         while (fpos < __le32_to_cpu(diro->inode.size)) {
1910                 struct ext2_dirent dirent;
1911
1912                 status = ext4fs_read_file(diro, fpos,
1913                                            sizeof(struct ext2_dirent),
1914                                            (char *)&dirent, &actread);
1915                 if (status < 0)
1916                         return 0;
1917
1918                 if (dirent.namelen != 0) {
1919                         char filename[dirent.namelen + 1];
1920                         struct ext2fs_node *fdiro;
1921                         int type = FILETYPE_UNKNOWN;
1922
1923                         status = ext4fs_read_file(diro,
1924                                                   fpos +
1925                                                   sizeof(struct ext2_dirent),
1926                                                   dirent.namelen, filename,
1927                                                   &actread);
1928                         if (status < 0)
1929                                 return 0;
1930
1931                         fdiro = zalloc(sizeof(struct ext2fs_node));
1932                         if (!fdiro)
1933                                 return 0;
1934
1935                         fdiro->data = diro->data;
1936                         fdiro->ino = __le32_to_cpu(dirent.inode);
1937
1938                         filename[dirent.namelen] = '\0';
1939
1940                         if (dirent.filetype != FILETYPE_UNKNOWN) {
1941                                 fdiro->inode_read = 0;
1942
1943                                 if (dirent.filetype == FILETYPE_DIRECTORY)
1944                                         type = FILETYPE_DIRECTORY;
1945                                 else if (dirent.filetype == FILETYPE_SYMLINK)
1946                                         type = FILETYPE_SYMLINK;
1947                                 else if (dirent.filetype == FILETYPE_REG)
1948                                         type = FILETYPE_REG;
1949                         } else {
1950                                 status = ext4fs_read_inode(diro->data,
1951                                                            __le32_to_cpu
1952                                                            (dirent.inode),
1953                                                            &fdiro->inode);
1954                                 if (status == 0) {
1955                                         free(fdiro);
1956                                         return 0;
1957                                 }
1958                                 fdiro->inode_read = 1;
1959
1960                                 if ((__le16_to_cpu(fdiro->inode.mode) &
1961                                      FILETYPE_INO_MASK) ==
1962                                     FILETYPE_INO_DIRECTORY) {
1963                                         type = FILETYPE_DIRECTORY;
1964                                 } else if ((__le16_to_cpu(fdiro->inode.mode)
1965                                             & FILETYPE_INO_MASK) ==
1966                                            FILETYPE_INO_SYMLINK) {
1967                                         type = FILETYPE_SYMLINK;
1968                                 } else if ((__le16_to_cpu(fdiro->inode.mode)
1969                                             & FILETYPE_INO_MASK) ==
1970                                            FILETYPE_INO_REG) {
1971                                         type = FILETYPE_REG;
1972                                 }
1973                         }
1974 #ifdef DEBUG
1975                         printf("iterate >%s<\n", filename);
1976 #endif /* of DEBUG */
1977                         if ((name != NULL) && (fnode != NULL)
1978                             && (ftype != NULL)) {
1979                                 if (strcmp(filename, name) == 0) {
1980                                         *ftype = type;
1981                                         *fnode = fdiro;
1982                                         return 1;
1983                                 }
1984                         } else {
1985                                 if (fdiro->inode_read == 0) {
1986                                         status = ext4fs_read_inode(diro->data,
1987                                                                  __le32_to_cpu(
1988                                                                  dirent.inode),
1989                                                                  &fdiro->inode);
1990                                         if (status == 0) {
1991                                                 free(fdiro);
1992                                                 return 0;
1993                                         }
1994                                         fdiro->inode_read = 1;
1995                                 }
1996                                 switch (type) {
1997                                 case FILETYPE_DIRECTORY:
1998                                         printf("<DIR> ");
1999                                         break;
2000                                 case FILETYPE_SYMLINK:
2001                                         printf("<SYM> ");
2002                                         break;
2003                                 case FILETYPE_REG:
2004                                         printf("      ");
2005                                         break;
2006                                 default:
2007                                         printf("< ? > ");
2008                                         break;
2009                                 }
2010                                 printf("%10u %s\n",
2011                                        __le32_to_cpu(fdiro->inode.size),
2012                                         filename);
2013                         }
2014                         free(fdiro);
2015                 }
2016                 fpos += __le16_to_cpu(dirent.direntlen);
2017         }
2018         return 0;
2019 }
2020
2021 static char *ext4fs_read_symlink(struct ext2fs_node *node)
2022 {
2023         char *symlink;
2024         struct ext2fs_node *diro = node;
2025         int status;
2026         loff_t actread;
2027
2028         if (!diro->inode_read) {
2029                 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode);
2030                 if (status == 0)
2031                         return 0;
2032         }
2033         symlink = zalloc(__le32_to_cpu(diro->inode.size) + 1);
2034         if (!symlink)
2035                 return 0;
2036
2037         if (__le32_to_cpu(diro->inode.size) <= 60) {
2038                 strncpy(symlink, diro->inode.b.symlink,
2039                          __le32_to_cpu(diro->inode.size));
2040         } else {
2041                 status = ext4fs_read_file(diro, 0,
2042                                            __le32_to_cpu(diro->inode.size),
2043                                            symlink, &actread);
2044                 if (status == 0) {
2045                         free(symlink);
2046                         return 0;
2047                 }
2048         }
2049         symlink[__le32_to_cpu(diro->inode.size)] = '\0';
2050         return symlink;
2051 }
2052
2053 static int ext4fs_find_file1(const char *currpath,
2054                              struct ext2fs_node *currroot,
2055                              struct ext2fs_node **currfound, int *foundtype)
2056 {
2057         char fpath[strlen(currpath) + 1];
2058         char *name = fpath;
2059         char *next;
2060         int status;
2061         int type = FILETYPE_DIRECTORY;
2062         struct ext2fs_node *currnode = currroot;
2063         struct ext2fs_node *oldnode = currroot;
2064
2065         strncpy(fpath, currpath, strlen(currpath) + 1);
2066
2067         /* Remove all leading slashes. */
2068         while (*name == '/')
2069                 name++;
2070
2071         if (!*name) {
2072                 *currfound = currnode;
2073                 return 1;
2074         }
2075
2076         for (;;) {
2077                 int found;
2078
2079                 /* Extract the actual part from the pathname. */
2080                 next = strchr(name, '/');
2081                 if (next) {
2082                         /* Remove all leading slashes. */
2083                         while (*next == '/')
2084                                 *(next++) = '\0';
2085                 }
2086
2087                 if (type != FILETYPE_DIRECTORY) {
2088                         ext4fs_free_node(currnode, currroot);
2089                         return 0;
2090                 }
2091
2092                 oldnode = currnode;
2093
2094                 /* Iterate over the directory. */
2095                 found = ext4fs_iterate_dir(currnode, name, &currnode, &type);
2096                 if (found == 0)
2097                         return 0;
2098
2099                 if (found == -1)
2100                         break;
2101
2102                 /* Read in the symlink and follow it. */
2103                 if (type == FILETYPE_SYMLINK) {
2104                         char *symlink;
2105
2106                         /* Test if the symlink does not loop. */
2107                         if (++symlinknest == 8) {
2108                                 ext4fs_free_node(currnode, currroot);
2109                                 ext4fs_free_node(oldnode, currroot);
2110                                 return 0;
2111                         }
2112
2113                         symlink = ext4fs_read_symlink(currnode);
2114                         ext4fs_free_node(currnode, currroot);
2115
2116                         if (!symlink) {
2117                                 ext4fs_free_node(oldnode, currroot);
2118                                 return 0;
2119                         }
2120
2121                         debug("Got symlink >%s<\n", symlink);
2122
2123                         if (symlink[0] == '/') {
2124                                 ext4fs_free_node(oldnode, currroot);
2125                                 oldnode = &ext4fs_root->diropen;
2126                         }
2127
2128                         /* Lookup the node the symlink points to. */
2129                         status = ext4fs_find_file1(symlink, oldnode,
2130                                                     &currnode, &type);
2131
2132                         free(symlink);
2133
2134                         if (status == 0) {
2135                                 ext4fs_free_node(oldnode, currroot);
2136                                 return 0;
2137                         }
2138                 }
2139
2140                 ext4fs_free_node(oldnode, currroot);
2141
2142                 /* Found the node! */
2143                 if (!next || *next == '\0') {
2144                         *currfound = currnode;
2145                         *foundtype = type;
2146                         return 1;
2147                 }
2148                 name = next;
2149         }
2150         return -1;
2151 }
2152
2153 int ext4fs_find_file(const char *path, struct ext2fs_node *rootnode,
2154         struct ext2fs_node **foundnode, int expecttype)
2155 {
2156         int status;
2157         int foundtype = FILETYPE_DIRECTORY;
2158
2159         symlinknest = 0;
2160         if (!path)
2161                 return 0;
2162
2163         status = ext4fs_find_file1(path, rootnode, foundnode, &foundtype);
2164         if (status == 0)
2165                 return 0;
2166
2167         /* Check if the node that was found was of the expected type. */
2168         if ((expecttype == FILETYPE_REG) && (foundtype != expecttype))
2169                 return 0;
2170         else if ((expecttype == FILETYPE_DIRECTORY)
2171                    && (foundtype != expecttype))
2172                 return 0;
2173
2174         return 1;
2175 }
2176
2177 int ext4fs_open(const char *filename, loff_t *len)
2178 {
2179         struct ext2fs_node *fdiro = NULL;
2180         int status;
2181
2182         if (ext4fs_root == NULL)
2183                 return -1;
2184
2185         ext4fs_file = NULL;
2186         status = ext4fs_find_file(filename, &ext4fs_root->diropen, &fdiro,
2187                                   FILETYPE_REG);
2188         if (status == 0)
2189                 goto fail;
2190
2191         if (!fdiro->inode_read) {
2192                 status = ext4fs_read_inode(fdiro->data, fdiro->ino,
2193                                 &fdiro->inode);
2194                 if (status == 0)
2195                         goto fail;
2196         }
2197         *len = __le32_to_cpu(fdiro->inode.size);
2198         ext4fs_file = fdiro;
2199
2200         return 0;
2201 fail:
2202         ext4fs_free_node(fdiro, &ext4fs_root->diropen);
2203
2204         return -1;
2205 }
2206
2207 int ext4fs_mount(unsigned part_length)
2208 {
2209         struct ext2_data *data;
2210         int status;
2211         struct ext_filesystem *fs = get_fs();
2212         data = zalloc(SUPERBLOCK_SIZE);
2213         if (!data)
2214                 return 0;
2215
2216         /* Read the superblock. */
2217         status = ext4_read_superblock((char *)&data->sblock);
2218
2219         if (status == 0)
2220                 goto fail;
2221
2222         /* Make sure this is an ext2 filesystem. */
2223         if (__le16_to_cpu(data->sblock.magic) != EXT2_MAGIC)
2224                 goto fail;
2225
2226         if (__le32_to_cpu(data->sblock.revision_level == 0))
2227                 fs->inodesz = 128;
2228         else
2229                 fs->inodesz = __le16_to_cpu(data->sblock.inode_size);
2230
2231         debug("EXT2 rev %d, inode_size %d\n",
2232                __le32_to_cpu(data->sblock.revision_level), fs->inodesz);
2233
2234         data->diropen.data = data;
2235         data->diropen.ino = 2;
2236         data->diropen.inode_read = 1;
2237         data->inode = &data->diropen.inode;
2238
2239         status = ext4fs_read_inode(data, 2, data->inode);
2240         if (status == 0)
2241                 goto fail;
2242
2243         ext4fs_root = data;
2244
2245         return 1;
2246 fail:
2247         printf("Failed to mount ext2 filesystem...\n");
2248         free(data);
2249         ext4fs_root = NULL;
2250
2251         return 0;
2252 }