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  * This program is free software; you can redistribute it and/or modify
  20  * it under the terms of the GNU General Public License as published by
  21  * the Free Software Foundation; either version 2 of the License, or
  22  * (at your option) any later version.
  23  *
  24  * This program is distributed in the hope that it will be useful,
  25  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  26  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  27  * GNU General Public License for more details.
  28  *
  29  * You should have received a copy of the GNU General Public License
  30  * along with this program; if not, write to the Free Software
  31  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  32  */
  33
  34 #include <common.h>
  35 #include <ext_common.h>
  36 #include <ext4fs.h>
  37 #include <malloc.h>
  38 #include <stddef.h>
  39 #include <linux/stat.h>
  40 #include <linux/time.h>
  41 #include <asm/byteorder.h>
  42 #include "ext4_common.h"
  43
  44 struct ext2_data *ext4fs_root;
  45 struct ext2fs_node *ext4fs_file;
  46 uint32_t *ext4fs_indir1_block;
  47 int ext4fs_indir1_size;
  48 int ext4fs_indir1_blkno = -1;
  49 uint32_t *ext4fs_indir2_block;
  50 int ext4fs_indir2_size;
  51 int ext4fs_indir2_blkno = -1;
  52
  53 uint32_t *ext4fs_indir3_block;
  54 int ext4fs_indir3_size;
  55 int ext4fs_indir3_blkno = -1;
  56 struct ext2_inode *g_parent_inode;
  57 static int symlinknest;
  58
  59 #if defined(CONFIG_EXT4_WRITE)
  60 uint32_t ext4fs_div_roundup(uint32_t size, uint32_t n)
  61 {
  62         uint32_t res = size / n;
  63         if (res * n != size)
  64                 res++;
  65
  66         return res;
  67 }
  68
  69 void put_ext4(uint64_t off, void *buf, uint32_t size)
  70 {
  71         uint64_t startblock;
  72         uint64_t remainder;
  73         unsigned char *temp_ptr = NULL;
  74         struct ext_filesystem *fs = get_fs();
  75         int log2blksz = fs->dev_desc->log2blksz;
  76         ALLOC_CACHE_ALIGN_BUFFER(unsigned char, sec_buf, fs->dev_desc->blksz);
  77
  78         startblock = off >> log2blksz;
  79         startblock += part_offset;
  80         remainder = off & (uint64_t)(fs->dev_desc->blksz - 1);
  81
  82         if (fs->dev_desc == NULL)
  83                 return;
  84
  85         if ((startblock + (size >> log2blksz)) >
  86             (part_offset + fs->total_sect)) {
  87                 printf("part_offset is %lu\n", part_offset);
  88                 printf("total_sector is %llu\n", fs->total_sect);
  89                 printf("error: overflow occurs\n");
  90                 return;
  91         }
  92
  93         if (remainder) {
  94                 if (fs->dev_desc->block_read) {
  95                         fs->dev_desc->block_read(fs->dev_desc->dev,
  96                                                  startblock, 1, sec_buf);
  97                         temp_ptr = sec_buf;
  98                         memcpy((temp_ptr + remainder),
  99                                (unsigned char *)buf, size);
 100                         fs->dev_desc->block_write(fs->dev_desc->dev,
 101                                                   startblock, 1, sec_buf);
 102                 }
 103         } else {
 104                 if (size >> log2blksz != 0) {
 105                         fs->dev_desc->block_write(fs->dev_desc->dev,
 106                                                   startblock,
 107                                                   size >> log2blksz,
 108                                                   (unsigned long *)buf);
 109                 } else {
 110                         fs->dev_desc->block_read(fs->dev_desc->dev,
 111                                                  startblock, 1, sec_buf);
 112                         temp_ptr = sec_buf;
 113                         memcpy(temp_ptr, buf, size);
 114                         fs->dev_desc->block_write(fs->dev_desc->dev,
 115                                                   startblock, 1,
 116                                                   (unsigned long *)sec_buf);
 117                 }
 118         }
 119 }
 120
 121 static int _get_new_inode_no(unsigned char *buffer)
 122 {
 123         struct ext_filesystem *fs = get_fs();
 124         unsigned char input;
 125         int operand, status;
 126         int count = 1;
 127         int j = 0;
 128
 129         /* get the blocksize of the filesystem */
 130         unsigned char *ptr = buffer;
 131         while (*ptr == 255) {
 132                 ptr++;
 133                 count += 8;
 134                 if (count > ext4fs_root->sblock.inodes_per_group)
 135                         return -1;
 136         }
 137
 138         for (j = 0; j < fs->blksz; j++) {
 139                 input = *ptr;
 140                 int i = 0;
 141                 while (i <= 7) {
 142                         operand = 1 << i;
 143                         status = input & operand;
 144                         if (status) {
 145                                 i++;
 146                                 count++;
 147                         } else {
 148                                 *ptr |= operand;
 149                                 return count;
 150                         }
 151                 }
 152                 ptr = ptr + 1;
 153         }
 154
 155         return -1;
 156 }
 157
 158 static int _get_new_blk_no(unsigned char *buffer)
 159 {
 160         unsigned char input;
 161         int operand, status;
 162         int count = 0;
 163         int j = 0;
 164         unsigned char *ptr = buffer;
 165         struct ext_filesystem *fs = get_fs();
 166
 167         if (fs->blksz != 1024)
 168                 count = 0;
 169         else
 170                 count = 1;
 171
 172         while (*ptr == 255) {
 173                 ptr++;
 174                 count += 8;
 175                 if (count == (fs->blksz * 8))
 176                         return -1;
 177         }
 178
 179         for (j = 0; j < fs->blksz; j++) {
 180                 input = *ptr;
 181                 int i = 0;
 182                 while (i <= 7) {
 183                         operand = 1 << i;
 184                         status = input & operand;
 185                         if (status) {
 186                                 i++;
 187                                 count++;
 188                         } else {
 189                                 *ptr |= operand;
 190                                 return count;
 191                         }
 192                 }
 193                 ptr = ptr + 1;
 194         }
 195
 196         return -1;
 197 }
 198
 199 int ext4fs_set_block_bmap(long int blockno, unsigned char *buffer, int index)
 200 {
 201         int i, remainder, status;
 202         unsigned char *ptr = buffer;
 203         unsigned char operand;
 204         i = blockno / 8;
 205         remainder = blockno % 8;
 206         int blocksize = EXT2_BLOCK_SIZE(ext4fs_root);
 207
 208         i = i - (index * blocksize);
 209         if (blocksize != 1024) {
 210                 ptr = ptr + i;
 211                 operand = 1 << remainder;
 212                 status = *ptr & operand;
 213                 if (status)
 214                         return -1;
 215
 216                 *ptr = *ptr | operand;
 217                 return 0;
 218         } else {
 219                 if (remainder == 0) {
 220                         ptr = ptr + i - 1;
 221                         operand = (1 << 7);
 222                 } else {
 223                         ptr = ptr + i;
 224                         operand = (1 << (remainder - 1));
 225                 }
 226                 status = *ptr & operand;
 227                 if (status)
 228                         return -1;
 229
 230                 *ptr = *ptr | operand;
 231                 return 0;
 232         }
 233 }
 234
 235 void ext4fs_reset_block_bmap(long int blockno, unsigned char *buffer, int index)
 236 {
 237         int i, remainder, status;
 238         unsigned char *ptr = buffer;
 239         unsigned char operand;
 240         i = blockno / 8;
 241         remainder = blockno % 8;
 242         int blocksize = EXT2_BLOCK_SIZE(ext4fs_root);
 243
 244         i = i - (index * blocksize);
 245         if (blocksize != 1024) {
 246                 ptr = ptr + i;
 247                 operand = (1 << remainder);
 248                 status = *ptr & operand;
 249                 if (status)
 250                         *ptr = *ptr & ~(operand);
 251         } else {
 252                 if (remainder == 0) {
 253                         ptr = ptr + i - 1;
 254                         operand = (1 << 7);
 255                 } else {
 256                         ptr = ptr + i;
 257                         operand = (1 << (remainder - 1));
 258                 }
 259                 status = *ptr & operand;
 260                 if (status)
 261                         *ptr = *ptr & ~(operand);
 262         }
 263 }
 264
 265 int ext4fs_set_inode_bmap(int inode_no, unsigned char *buffer, int index)
 266 {
 267         int i, remainder, status;
 268         unsigned char *ptr = buffer;
 269         unsigned char operand;
 270
 271         inode_no -= (index * ext4fs_root->sblock.inodes_per_group);
 272         i = inode_no / 8;
 273         remainder = inode_no % 8;
 274         if (remainder == 0) {
 275                 ptr = ptr + i - 1;
 276                 operand = (1 << 7);
 277         } else {
 278                 ptr = ptr + i;
 279                 operand = (1 << (remainder - 1));
 280         }
 281         status = *ptr & operand;
 282         if (status)
 283                 return -1;
 284
 285         *ptr = *ptr | operand;
 286
 287         return 0;
 288 }
 289
 290 void ext4fs_reset_inode_bmap(int inode_no, unsigned char *buffer, int index)
 291 {
 292         int i, remainder, status;
 293         unsigned char *ptr = buffer;
 294         unsigned char operand;
 295
 296         inode_no -= (index * ext4fs_root->sblock.inodes_per_group);
 297         i = inode_no / 8;
 298         remainder = inode_no % 8;
 299         if (remainder == 0) {
 300                 ptr = ptr + i - 1;
 301                 operand = (1 << 7);
 302         } else {
 303                 ptr = ptr + i;
 304                 operand = (1 << (remainder - 1));
 305         }
 306         status = *ptr & operand;
 307         if (status)
 308                 *ptr = *ptr & ~(operand);
 309 }
 310
 311 int ext4fs_checksum_update(unsigned int i)
 312 {
 313         struct ext2_block_group *desc;
 314         struct ext_filesystem *fs = get_fs();
 315         __u16 crc = 0;
 316
 317         desc = (struct ext2_block_group *)&fs->bgd[i];
 318         if (fs->sb->feature_ro_compat & EXT4_FEATURE_RO_COMPAT_GDT_CSUM) {
 319                 int offset = offsetof(struct ext2_block_group, bg_checksum);
 320
 321                 crc = ext2fs_crc16(~0, fs->sb->unique_id,
 322                                    sizeof(fs->sb->unique_id));
 323                 crc = ext2fs_crc16(crc, &i, sizeof(i));
 324                 crc = ext2fs_crc16(crc, desc, offset);
 325                 offset += sizeof(desc->bg_checksum);    /* skip checksum */
 326                 assert(offset == sizeof(*desc));
 327         }
 328
 329         return crc;
 330 }
 331
 332 static int check_void_in_dentry(struct ext2_dirent *dir, char *filename)
 333 {
 334         int dentry_length;
 335         int sizeof_void_space;
 336         int new_entry_byte_reqd;
 337         short padding_factor = 0;
 338
 339         if (dir->namelen % 4 != 0)
 340                 padding_factor = 4 - (dir->namelen % 4);
 341
 342         dentry_length = sizeof(struct ext2_dirent) +
 343                         dir->namelen + padding_factor;
 344         sizeof_void_space = dir->direntlen - dentry_length;
 345         if (sizeof_void_space == 0)
 346                 return 0;
 347
 348         padding_factor = 0;
 349         if (strlen(filename) % 4 != 0)
 350                 padding_factor = 4 - (strlen(filename) % 4);
 351
 352         new_entry_byte_reqd = strlen(filename) +
 353             sizeof(struct ext2_dirent) + padding_factor;
 354         if (sizeof_void_space >= new_entry_byte_reqd) {
 355                 dir->direntlen = dentry_length;
 356                 return sizeof_void_space;
 357         }
 358
 359         return 0;
 360 }
 361
 362 void ext4fs_update_parent_dentry(char *filename, int *p_ino, int file_type)
 363 {
 364         unsigned int *zero_buffer = NULL;
 365         char *root_first_block_buffer = NULL;
 366         int direct_blk_idx;
 367         long int root_blknr;
 368         long int first_block_no_of_root = 0;
 369         long int previous_blknr = -1;
 370         int totalbytes = 0;
 371         short int padding_factor = 0;
 372         unsigned int new_entry_byte_reqd;
 373         unsigned int last_entry_dirlen;
 374         int sizeof_void_space = 0;
 375         int templength = 0;
 376         int inodeno;
 377         int status;
 378         struct ext_filesystem *fs = get_fs();
 379         /* directory entry */
 380         struct ext2_dirent *dir;
 381         char *temp_dir = NULL;
 382
 383         zero_buffer = zalloc(fs->blksz);
 384         if (!zero_buffer) {
 385                 printf("No Memory\n");
 386                 return;
 387         }
 388         root_first_block_buffer = zalloc(fs->blksz);
 389         if (!root_first_block_buffer) {
 390                 free(zero_buffer);
 391                 printf("No Memory\n");
 392                 return;
 393         }
 394 restart:
 395
 396         /* read the block no allocated to a file */
 397         for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS;
 398              direct_blk_idx++) {
 399                 root_blknr = read_allocated_block(g_parent_inode,
 400                                                   direct_blk_idx);
 401                 if (root_blknr == 0) {
 402                         first_block_no_of_root = previous_blknr;
 403                         break;
 404                 }
 405                 previous_blknr = root_blknr;
 406         }
 407
 408         status = ext4fs_devread(first_block_no_of_root
 409                                 * fs->sect_perblk,
 410                                 0, fs->blksz, root_first_block_buffer);
 411         if (status == 0)
 412                 goto fail;
 413
 414         if (ext4fs_log_journal(root_first_block_buffer, first_block_no_of_root))
 415                 goto fail;
 416         dir = (struct ext2_dirent *)root_first_block_buffer;
 417         totalbytes = 0;
 418         while (dir->direntlen > 0) {
 419                 /*
 420                  * blocksize-totalbytes because last directory length
 421                  * i.e. dir->direntlen is free availble space in the
 422                  * block that means  it is a last entry of directory
 423                  * entry
 424                  */
 425
 426                 /* traversing the each directory entry */
 427                 if (fs->blksz - totalbytes == dir->direntlen) {
 428                         if (strlen(filename) % 4 != 0)
 429                                 padding_factor = 4 - (strlen(filename) % 4);
 430
 431                         new_entry_byte_reqd = strlen(filename) +
 432                             sizeof(struct ext2_dirent) + padding_factor;
 433                         padding_factor = 0;
 434                         /*
 435                          * update last directory entry length to its
 436                          * length because we are creating new directory
 437                          * entry
 438                          */
 439                         if (dir->namelen % 4 != 0)
 440                                 padding_factor = 4 - (dir->namelen % 4);
 441
 442                         last_entry_dirlen = dir->namelen +
 443                             sizeof(struct ext2_dirent) + padding_factor;
 444                         if ((fs->blksz - totalbytes - last_entry_dirlen) <
 445                                 new_entry_byte_reqd) {
 446                                 printf("1st Block Full:Allocate new block\n");
 447
 448                                 if (direct_blk_idx == INDIRECT_BLOCKS - 1) {
 449                                         printf("Directory exceeds limit\n");
 450                                         goto fail;
 451                                 }
 452                                 g_parent_inode->b.blocks.dir_blocks
 453                                     [direct_blk_idx] = ext4fs_get_new_blk_no();
 454                                 if (g_parent_inode->b.blocks.dir_blocks
 455                                         [direct_blk_idx] == -1) {
 456                                         printf("no block left to assign\n");
 457                                         goto fail;
 458                                 }
 459                                 put_ext4(((uint64_t)
 460                                           (g_parent_inode->b.
 461                                            blocks.dir_blocks[direct_blk_idx] *
 462                                            fs->blksz)), zero_buffer, fs->blksz);
 463                                 g_parent_inode->size =
 464                                     g_parent_inode->size + fs->blksz;
 465                                 g_parent_inode->blockcnt =
 466                                     g_parent_inode->blockcnt + fs->sect_perblk;
 467                                 if (ext4fs_put_metadata
 468                                     (root_first_block_buffer,
 469                                      first_block_no_of_root))
 470                                         goto fail;
 471                                 goto restart;
 472                         }
 473                         dir->direntlen = last_entry_dirlen;
 474                         break;
 475                 }
 476
 477                 templength = dir->direntlen;
 478                 totalbytes = totalbytes + templength;
 479                 sizeof_void_space = check_void_in_dentry(dir, filename);
 480                 if (sizeof_void_space)
 481                         break;
 482
 483                 dir = (struct ext2_dirent *)((char *)dir + templength);
 484         }
 485
 486         /* make a pointer ready for creating next directory entry */
 487         templength = dir->direntlen;
 488         totalbytes = totalbytes + templength;
 489         dir = (struct ext2_dirent *)((char *)dir + templength);
 490
 491         /* get the next available inode number */
 492         inodeno = ext4fs_get_new_inode_no();
 493         if (inodeno == -1) {
 494                 printf("no inode left to assign\n");
 495                 goto fail;
 496         }
 497         dir->inode = inodeno;
 498         if (sizeof_void_space)
 499                 dir->direntlen = sizeof_void_space;
 500         else
 501                 dir->direntlen = fs->blksz - totalbytes;
 502
 503         dir->namelen = strlen(filename);
 504         dir->filetype = FILETYPE_REG;   /* regular file */
 505         temp_dir = (char *)dir;
 506         temp_dir = temp_dir + sizeof(struct ext2_dirent);
 507         memcpy(temp_dir, filename, strlen(filename));
 508
 509         *p_ino = inodeno;
 510
 511         /* update or write  the 1st block of root inode */
 512         if (ext4fs_put_metadata(root_first_block_buffer,
 513                                 first_block_no_of_root))
 514                 goto fail;
 515
 516 fail:
 517         free(zero_buffer);
 518         free(root_first_block_buffer);
 519 }
 520
 521 static int search_dir(struct ext2_inode *parent_inode, char *dirname)
 522 {
 523         int status;
 524         int inodeno;
 525         int totalbytes;
 526         int templength;
 527         int direct_blk_idx;
 528         long int blknr;
 529         int found = 0;
 530         char *ptr = NULL;
 531         unsigned char *block_buffer = NULL;
 532         struct ext2_dirent *dir = NULL;
 533         struct ext2_dirent *previous_dir = NULL;
 534         struct ext_filesystem *fs = get_fs();
 535
 536         /* read the block no allocated to a file */
 537         for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS;
 538                 direct_blk_idx++) {
 539                 blknr = read_allocated_block(parent_inode, direct_blk_idx);
 540                 if (blknr == 0)
 541                         goto fail;
 542
 543                 /* read the blocks of parenet inode */
 544                 block_buffer = zalloc(fs->blksz);
 545                 if (!block_buffer)
 546                         goto fail;
 547
 548                 status = ext4fs_devread(blknr * fs->sect_perblk,
 549                                         0, fs->blksz, (char *)block_buffer);
 550                 if (status == 0)
 551                         goto fail;
 552
 553                 dir = (struct ext2_dirent *)block_buffer;
 554                 ptr = (char *)dir;
 555                 totalbytes = 0;
 556                 while (dir->direntlen >= 0) {
 557                         /*
 558                          * blocksize-totalbytes because last directory
 559                          * length i.e.,*dir->direntlen is free availble
 560                          * space in the block that means
 561                          * it is a last entry of directory entry
 562                          */
 563                         if (strlen(dirname) == dir->namelen) {
 564                                 if (strncmp(dirname, ptr +
 565                                         sizeof(struct ext2_dirent),
 566                                         dir->namelen) == 0) {
 567                                         previous_dir->direntlen +=
 568                                                         dir->direntlen;
 569                                         inodeno = dir->inode;
 570                                         dir->inode = 0;
 571                                         found = 1;
 572                                         break;
 573                                 }
 574                         }
 575
 576                         if (fs->blksz - totalbytes == dir->direntlen)
 577                                 break;
 578
 579                         /* traversing the each directory entry */
 580                         templength = dir->direntlen;
 581                         totalbytes = totalbytes + templength;
 582                         previous_dir = dir;
 583                         dir = (struct ext2_dirent *)((char *)dir + templength);
 584                         ptr = (char *)dir;
 585                 }
 586
 587                 if (found == 1) {
 588                         free(block_buffer);
 589                         block_buffer = NULL;
 590                         return inodeno;
 591                 }
 592
 593                 free(block_buffer);
 594                 block_buffer = NULL;
 595         }
 596
 597 fail:
 598         free(block_buffer);
 599
 600         return -1;
 601 }
 602
 603 static int find_dir_depth(char *dirname)
 604 {
 605         char *token = strtok(dirname, "/");
 606         int count = 0;
 607         while (token != NULL) {
 608                 token = strtok(NULL, "/");
 609                 count++;
 610         }
 611         return count + 1 + 1;
 612         /*
 613          * for example  for string /home/temp
 614          * depth=home(1)+temp(1)+1 extra for NULL;
 615          * so count is 4;
 616          */
 617 }
 618
 619 static int parse_path(char **arr, char *dirname)
 620 {
 621         char *token = strtok(dirname, "/");
 622         int i = 0;
 623
 624         /* add root */
 625         arr[i] = zalloc(strlen("/") + 1);
 626         if (!arr[i])
 627                 return -ENOMEM;
 628
 629         arr[i++] = "/";
 630
 631         /* add each path entry after root */
 632         while (token != NULL) {
 633                 arr[i] = zalloc(strlen(token) + 1);
 634                 if (!arr[i])
 635                         return -ENOMEM;
 636                 memcpy(arr[i++], token, strlen(token));
 637                 token = strtok(NULL, "/");
 638         }
 639         arr[i] = NULL;
 640
 641         return 0;
 642 }
 643
 644 int ext4fs_iget(int inode_no, struct ext2_inode *inode)
 645 {
 646         if (ext4fs_read_inode(ext4fs_root, inode_no, inode) == 0)
 647                 return -1;
 648
 649         return 0;
 650 }
 651
 652 /*
 653  * Function: ext4fs_get_parent_inode_num
 654  * Return Value: inode Number of the parent directory of  file/Directory to be
 655  * created
 656  * dirname : Input parmater, input path name of the file/directory to be created
 657  * dname : Output parameter, to be filled with the name of the directory
 658  * extracted from dirname
 659  */
 660 int ext4fs_get_parent_inode_num(const char *dirname, char *dname, int flags)
 661 {
 662         int i;
 663         int depth = 0;
 664         int matched_inode_no;
 665         int result_inode_no = -1;
 666         char **ptr = NULL;
 667         char *depth_dirname = NULL;
 668         char *parse_dirname = NULL;
 669         struct ext2_inode *parent_inode = NULL;
 670         struct ext2_inode *first_inode = NULL;
 671         struct ext2_inode temp_inode;
 672
 673         if (*dirname != '/') {
 674                 printf("Please supply Absolute path\n");
 675                 return -1;
 676         }
 677
 678         /* TODO: input validation make equivalent to linux */
 679         depth_dirname = zalloc(strlen(dirname) + 1);
 680         if (!depth_dirname)
 681                 return -ENOMEM;
 682
 683         memcpy(depth_dirname, dirname, strlen(dirname));
 684         depth = find_dir_depth(depth_dirname);
 685         parse_dirname = zalloc(strlen(dirname) + 1);
 686         if (!parse_dirname)
 687                 goto fail;
 688         memcpy(parse_dirname, dirname, strlen(dirname));
 689
 690         /* allocate memory for each directory level */
 691         ptr = zalloc((depth) * sizeof(char *));
 692         if (!ptr)
 693                 goto fail;
 694         if (parse_path(ptr, parse_dirname))
 695                 goto fail;
 696         parent_inode = zalloc(sizeof(struct ext2_inode));
 697         if (!parent_inode)
 698                 goto fail;
 699         first_inode = zalloc(sizeof(struct ext2_inode));
 700         if (!first_inode)
 701                 goto fail;
 702         memcpy(parent_inode, ext4fs_root->inode, sizeof(struct ext2_inode));
 703         memcpy(first_inode, parent_inode, sizeof(struct ext2_inode));
 704         if (flags & F_FILE)
 705                 result_inode_no = EXT2_ROOT_INO;
 706         for (i = 1; i < depth; i++) {
 707                 matched_inode_no = search_dir(parent_inode, ptr[i]);
 708                 if (matched_inode_no == -1) {
 709                         if (ptr[i + 1] == NULL && i == 1) {
 710                                 result_inode_no = EXT2_ROOT_INO;
 711                                 goto end;
 712                         } else {
 713                                 if (ptr[i + 1] == NULL)
 714                                         break;
 715                                 printf("Invalid path\n");
 716                                 result_inode_no = -1;
 717                                 goto fail;
 718                         }
 719                 } else {
 720                         if (ptr[i + 1] != NULL) {
 721                                 memset(parent_inode, '\0',
 722                                        sizeof(struct ext2_inode));
 723                                 if (ext4fs_iget(matched_inode_no,
 724                                                 parent_inode)) {
 725                                         result_inode_no = -1;
 726                                         goto fail;
 727                                 }
 728                                 result_inode_no = matched_inode_no;
 729                         } else {
 730                                 break;
 731                         }
 732                 }
 733         }
 734
 735 end:
 736         if (i == 1)
 737                 matched_inode_no = search_dir(first_inode, ptr[i]);
 738         else
 739                 matched_inode_no = search_dir(parent_inode, ptr[i]);
 740
 741         if (matched_inode_no != -1) {
 742                 ext4fs_iget(matched_inode_no, &temp_inode);
 743                 if (temp_inode.mode & S_IFDIR) {
 744                         printf("It is a Directory\n");
 745                         result_inode_no = -1;
 746                         goto fail;
 747                 }
 748         }
 749
 750         if (strlen(ptr[i]) > 256) {
 751                 result_inode_no = -1;
 752                 goto fail;
 753         }
 754         memcpy(dname, ptr[i], strlen(ptr[i]));
 755
 756 fail:
 757         free(depth_dirname);
 758         free(parse_dirname);
 759         free(ptr);
 760         free(parent_inode);
 761         free(first_inode);
 762
 763         return result_inode_no;
 764 }
 765
 766 static int check_filename(char *filename, unsigned int blknr)
 767 {
 768         unsigned int first_block_no_of_root;
 769         int totalbytes = 0;
 770         int templength = 0;
 771         int status, inodeno;
 772         int found = 0;
 773         char *root_first_block_buffer = NULL;
 774         char *root_first_block_addr = NULL;
 775         struct ext2_dirent *dir = NULL;
 776         struct ext2_dirent *previous_dir = NULL;
 777         char *ptr = NULL;
 778         struct ext_filesystem *fs = get_fs();
 779
 780         /* get the first block of root */
 781         first_block_no_of_root = blknr;
 782         root_first_block_buffer = zalloc(fs->blksz);
 783         if (!root_first_block_buffer)
 784                 return -ENOMEM;
 785         root_first_block_addr = root_first_block_buffer;
 786         status = ext4fs_devread(first_block_no_of_root *
 787                                 fs->sect_perblk, 0,
 788                                 fs->blksz, root_first_block_buffer);
 789         if (status == 0)
 790                 goto fail;
 791
 792         if (ext4fs_log_journal(root_first_block_buffer, first_block_no_of_root))
 793                 goto fail;
 794         dir = (struct ext2_dirent *)root_first_block_buffer;
 795         ptr = (char *)dir;
 796         totalbytes = 0;
 797         while (dir->direntlen >= 0) {
 798                 /*
 799                  * blocksize-totalbytes because last
 800                  * directory length i.e., *dir->direntlen
 801                  * is free availble space in the block that
 802                  * means it is a last entry of directory entry
 803                  */
 804                 if (strlen(filename) == dir->namelen) {
 805                         if (strncmp(filename, ptr + sizeof(struct ext2_dirent),
 806                                 dir->namelen) == 0) {
 807                                 printf("file found deleting\n");
 808                                 previous_dir->direntlen += dir->direntlen;
 809                                 inodeno = dir->inode;
 810                                 dir->inode = 0;
 811                                 found = 1;
 812                                 break;
 813                         }
 814                 }
 815
 816                 if (fs->blksz - totalbytes == dir->direntlen)
 817                         break;
 818
 819                 /* traversing the each directory entry */
 820                 templength = dir->direntlen;
 821                 totalbytes = totalbytes + templength;
 822                 previous_dir = dir;
 823                 dir = (struct ext2_dirent *)((char *)dir + templength);
 824                 ptr = (char *)dir;
 825         }
 826
 827
 828         if (found == 1) {
 829                 if (ext4fs_put_metadata(root_first_block_addr,
 830                                         first_block_no_of_root))
 831                         goto fail;
 832                 return inodeno;
 833         }
 834 fail:
 835         free(root_first_block_buffer);
 836
 837         return -1;
 838 }
 839
 840 int ext4fs_filename_check(char *filename)
 841 {
 842         short direct_blk_idx = 0;
 843         long int blknr = -1;
 844         int inodeno = -1;
 845
 846         /* read the block no allocated to a file */
 847         for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS;
 848                 direct_blk_idx++) {
 849                 blknr = read_allocated_block(g_parent_inode, direct_blk_idx);
 850                 if (blknr == 0)
 851                         break;
 852                 inodeno = check_filename(filename, blknr);
 853                 if (inodeno != -1)
 854                         return inodeno;
 855         }
 856
 857         return -1;
 858 }
 859
 860 long int ext4fs_get_new_blk_no(void)
 861 {
 862         short i;
 863         short status;
 864         int remainder;
 865         unsigned int bg_idx;
 866         static int prev_bg_bitmap_index = -1;
 867         unsigned int blk_per_grp = ext4fs_root->sblock.blocks_per_group;
 868         struct ext_filesystem *fs = get_fs();
 869         char *journal_buffer = zalloc(fs->blksz);
 870         char *zero_buffer = zalloc(fs->blksz);
 871         if (!journal_buffer || !zero_buffer)
 872                 goto fail;
 873         struct ext2_block_group *bgd = (struct ext2_block_group *)fs->gdtable;
 874
 875         if (fs->first_pass_bbmap == 0) {
 876                 for (i = 0; i < fs->no_blkgrp; i++) {
 877                         if (bgd[i].free_blocks) {
 878                                 if (bgd[i].bg_flags & EXT4_BG_BLOCK_UNINIT) {
 879                                         put_ext4(((uint64_t) (bgd[i].block_id *
 880                                                               fs->blksz)),
 881                                                  zero_buffer, fs->blksz);
 882                                         bgd[i].bg_flags =
 883                                             bgd[i].
 884                                             bg_flags & ~EXT4_BG_BLOCK_UNINIT;
 885                                         memcpy(fs->blk_bmaps[i], zero_buffer,
 886                                                fs->blksz);
 887                                 }
 888                                 fs->curr_blkno =
 889                                     _get_new_blk_no(fs->blk_bmaps[i]);
 890                                 if (fs->curr_blkno == -1)
 891                                         /* if block bitmap is completely fill */
 892                                         continue;
 893                                 fs->curr_blkno = fs->curr_blkno +
 894                                                 (i * fs->blksz * 8);
 895                                 fs->first_pass_bbmap++;
 896                                 bgd[i].free_blocks--;
 897                                 fs->sb->free_blocks--;
 898                                 status = ext4fs_devread(bgd[i].block_id *
 899                                                         fs->sect_perblk, 0,
 900                                                         fs->blksz,
 901                                                         journal_buffer);
 902                                 if (status == 0)
 903                                         goto fail;
 904                                 if (ext4fs_log_journal(journal_buffer,
 905                                                         bgd[i].block_id))
 906                                         goto fail;
 907                                 goto success;
 908                         } else {
 909                                 debug("no space left on block group %d\n", i);
 910                         }
 911                 }
 912
 913                 goto fail;
 914         } else {
 915 restart:
 916                 fs->curr_blkno++;
 917                 /* get the blockbitmap index respective to blockno */
 918                 if (fs->blksz != 1024) {
 919                         bg_idx = fs->curr_blkno / blk_per_grp;
 920                 } else {
 921                         bg_idx = fs->curr_blkno / blk_per_grp;
 922                         remainder = fs->curr_blkno % blk_per_grp;
 923                         if (!remainder)
 924                                 bg_idx--;
 925                 }
 926
 927                 /*
 928                  * To skip completely filled block group bitmaps
 929                  * Optimize the block allocation
 930                  */
 931                 if (bg_idx >= fs->no_blkgrp)
 932                         goto fail;
 933
 934                 if (bgd[bg_idx].free_blocks == 0) {
 935                         debug("block group %u is full. Skipping\n", bg_idx);
 936                         fs->curr_blkno = fs->curr_blkno + blk_per_grp;
 937                         fs->curr_blkno--;
 938                         goto restart;
 939                 }
 940
 941                 if (bgd[bg_idx].bg_flags & EXT4_BG_BLOCK_UNINIT) {
 942                         memset(zero_buffer, '\0', fs->blksz);
 943                         put_ext4(((uint64_t) (bgd[bg_idx].block_id *
 944                                         fs->blksz)), zero_buffer, fs->blksz);
 945                         memcpy(fs->blk_bmaps[bg_idx], zero_buffer, fs->blksz);
 946                         bgd[bg_idx].bg_flags = bgd[bg_idx].bg_flags &
 947                                                 ~EXT4_BG_BLOCK_UNINIT;
 948                 }
 949
 950                 if (ext4fs_set_block_bmap(fs->curr_blkno, fs->blk_bmaps[bg_idx],
 951                                    bg_idx) != 0) {
 952                         debug("going for restart for the block no %ld %u\n",
 953                               fs->curr_blkno, bg_idx);
 954                         goto restart;
 955                 }
 956
 957                 /* journal backup */
 958                 if (prev_bg_bitmap_index != bg_idx) {
 959                         memset(journal_buffer, '\0', fs->blksz);
 960                         status = ext4fs_devread(bgd[bg_idx].block_id
 961                                                 * fs->sect_perblk,
 962                                                 0, fs->blksz, journal_buffer);
 963                         if (status == 0)
 964                                 goto fail;
 965                         if (ext4fs_log_journal(journal_buffer,
 966                                                 bgd[bg_idx].block_id))
 967                                 goto fail;
 968
 969                         prev_bg_bitmap_index = bg_idx;
 970                 }
 971                 bgd[bg_idx].free_blocks--;
 972                 fs->sb->free_blocks--;
 973                 goto success;
 974         }
 975 success:
 976         free(journal_buffer);
 977         free(zero_buffer);
 978
 979         return fs->curr_blkno;
 980 fail:
 981         free(journal_buffer);
 982         free(zero_buffer);
 983
 984         return -1;
 985 }
 986
 987 int ext4fs_get_new_inode_no(void)
 988 {
 989         short i;
 990         short status;
 991         unsigned int ibmap_idx;
 992         static int prev_inode_bitmap_index = -1;
 993         unsigned int inodes_per_grp = ext4fs_root->sblock.inodes_per_group;
 994         struct ext_filesystem *fs = get_fs();
 995         char *journal_buffer = zalloc(fs->blksz);
 996         char *zero_buffer = zalloc(fs->blksz);
 997         if (!journal_buffer || !zero_buffer)
 998                 goto fail;
 999         struct ext2_block_group *bgd = (struct ext2_block_group *)fs->gdtable;
1000
1001         if (fs->first_pass_ibmap == 0) {
1002                 for (i = 0; i < fs->no_blkgrp; i++) {
1003                         if (bgd[i].free_inodes) {
1004                                 if (bgd[i].bg_itable_unused !=
1005                                                 bgd[i].free_inodes)
1006                                         bgd[i].bg_itable_unused =
1007                                                 bgd[i].free_inodes;
1008                                 if (bgd[i].bg_flags & EXT4_BG_INODE_UNINIT) {
1009                                         put_ext4(((uint64_t)
1010                                                   (bgd[i].inode_id *
1011                                                         fs->blksz)),
1012                                                  zero_buffer, fs->blksz);
1013                                         bgd[i].bg_flags = bgd[i].bg_flags &
1014                                                         ~EXT4_BG_INODE_UNINIT;
1015                                         memcpy(fs->inode_bmaps[i],
1016                                                zero_buffer, fs->blksz);
1017                                 }
1018                                 fs->curr_inode_no =
1019                                     _get_new_inode_no(fs->inode_bmaps[i]);
1020                                 if (fs->curr_inode_no == -1)
1021                                         /* if block bitmap is completely fill */
1022                                         continue;
1023                                 fs->curr_inode_no = fs->curr_inode_no +
1024                                                         (i * inodes_per_grp);
1025                                 fs->first_pass_ibmap++;
1026                                 bgd[i].free_inodes--;
1027                                 bgd[i].bg_itable_unused--;
1028                                 fs->sb->free_inodes--;
1029                                 status = ext4fs_devread(bgd[i].inode_id *
1030                                                         fs->sect_perblk, 0,
1031                                                         fs->blksz,
1032                                                         journal_buffer);
1033                                 if (status == 0)
1034                                         goto fail;
1035                                 if (ext4fs_log_journal(journal_buffer,
1036                                                         bgd[i].inode_id))
1037                                         goto fail;
1038                                 goto success;
1039                         } else
1040                                 debug("no inode left on block group %d\n", i);
1041                 }
1042                 goto fail;
1043         } else {
1044 restart:
1045                 fs->curr_inode_no++;
1046                 /* get the blockbitmap index respective to blockno */
1047                 ibmap_idx = fs->curr_inode_no / inodes_per_grp;
1048                 if (bgd[ibmap_idx].bg_flags & EXT4_BG_INODE_UNINIT) {
1049                         memset(zero_buffer, '\0', fs->blksz);
1050                         put_ext4(((uint64_t) (bgd[ibmap_idx].inode_id *
1051                                               fs->blksz)), zero_buffer,
1052                                  fs->blksz);
1053                         bgd[ibmap_idx].bg_flags =
1054                             bgd[ibmap_idx].bg_flags & ~EXT4_BG_INODE_UNINIT;
1055                         memcpy(fs->inode_bmaps[ibmap_idx], zero_buffer,
1056                                 fs->blksz);
1057                 }
1058
1059                 if (ext4fs_set_inode_bmap(fs->curr_inode_no,
1060                                           fs->inode_bmaps[ibmap_idx],
1061                                           ibmap_idx) != 0) {
1062                         debug("going for restart for the block no %d %u\n",
1063                               fs->curr_inode_no, ibmap_idx);
1064                         goto restart;
1065                 }
1066
1067                 /* journal backup */
1068                 if (prev_inode_bitmap_index != ibmap_idx) {
1069                         memset(journal_buffer, '\0', fs->blksz);
1070                         status = ext4fs_devread(bgd[ibmap_idx].inode_id
1071                                                 * fs->sect_perblk,
1072                                                 0, fs->blksz, journal_buffer);
1073                         if (status == 0)
1074                                 goto fail;
1075                         if (ext4fs_log_journal(journal_buffer,
1076                                                 bgd[ibmap_idx].inode_id))
1077                                 goto fail;
1078                         prev_inode_bitmap_index = ibmap_idx;
1079                 }
1080                 if (bgd[ibmap_idx].bg_itable_unused !=
1081                                 bgd[ibmap_idx].free_inodes)
1082                         bgd[ibmap_idx].bg_itable_unused =
1083                                         bgd[ibmap_idx].free_inodes;
1084                 bgd[ibmap_idx].free_inodes--;
1085                 bgd[ibmap_idx].bg_itable_unused--;
1086                 fs->sb->free_inodes--;
1087                 goto success;
1088         }
1089
1090 success:
1091         free(journal_buffer);
1092         free(zero_buffer);
1093
1094         return fs->curr_inode_no;
1095 fail:
1096         free(journal_buffer);
1097         free(zero_buffer);
1098
1099         return -1;
1100
1101 }
1102
1103
1104 static void alloc_single_indirect_block(struct ext2_inode *file_inode,
1105                                         unsigned int *total_remaining_blocks,
1106                                         unsigned int *no_blks_reqd)
1107 {
1108         short i;
1109         short status;
1110         long int actual_block_no;
1111         long int si_blockno;
1112         /* si :single indirect */
1113         unsigned int *si_buffer = NULL;
1114         unsigned int *si_start_addr = NULL;
1115         struct ext_filesystem *fs = get_fs();
1116
1117         if (*total_remaining_blocks != 0) {
1118                 si_buffer = zalloc(fs->blksz);
1119                 if (!si_buffer) {
1120                         printf("No Memory\n");
1121                         return;
1122                 }
1123                 si_start_addr = si_buffer;
1124                 si_blockno = ext4fs_get_new_blk_no();
1125                 if (si_blockno == -1) {
1126                         printf("no block left to assign\n");
1127                         goto fail;
1128                 }
1129                 (*no_blks_reqd)++;
1130                 debug("SIPB %ld: %u\n", si_blockno, *total_remaining_blocks);
1131
1132                 status = ext4fs_devread(si_blockno * fs->sect_perblk,
1133                                         0, fs->blksz, (char *)si_buffer);
1134                 memset(si_buffer, '\0', fs->blksz);
1135                 if (status == 0)
1136                         goto fail;
1137
1138                 for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
1139                         actual_block_no = ext4fs_get_new_blk_no();
1140                         if (actual_block_no == -1) {
1141                                 printf("no block left to assign\n");
1142                                 goto fail;
1143                         }
1144                         *si_buffer = actual_block_no;
1145                         debug("SIAB %u: %u\n", *si_buffer,
1146                                 *total_remaining_blocks);
1147
1148                         si_buffer++;
1149                         (*total_remaining_blocks)--;
1150                         if (*total_remaining_blocks == 0)
1151                                 break;
1152                 }
1153
1154                 /* write the block to disk */
1155                 put_ext4(((uint64_t) (si_blockno * fs->blksz)),
1156                          si_start_addr, fs->blksz);
1157                 file_inode->b.blocks.indir_block = si_blockno;
1158         }
1159 fail:
1160         free(si_start_addr);
1161 }
1162
1163 static void alloc_double_indirect_block(struct ext2_inode *file_inode,
1164                                         unsigned int *total_remaining_blocks,
1165                                         unsigned int *no_blks_reqd)
1166 {
1167         short i;
1168         short j;
1169         short status;
1170         long int actual_block_no;
1171         /* di:double indirect */
1172         long int di_blockno_parent;
1173         long int di_blockno_child;
1174         unsigned int *di_parent_buffer = NULL;
1175         unsigned int *di_child_buff = NULL;
1176         unsigned int *di_block_start_addr = NULL;
1177         unsigned int *di_child_buff_start = NULL;
1178         struct ext_filesystem *fs = get_fs();
1179
1180         if (*total_remaining_blocks != 0) {
1181                 /* double indirect parent block connecting to inode */
1182                 di_blockno_parent = ext4fs_get_new_blk_no();
1183                 if (di_blockno_parent == -1) {
1184                         printf("no block left to assign\n");
1185                         goto fail;
1186                 }
1187                 di_parent_buffer = zalloc(fs->blksz);
1188                 if (!di_parent_buffer)
1189                         goto fail;
1190
1191                 di_block_start_addr = di_parent_buffer;
1192                 (*no_blks_reqd)++;
1193                 debug("DIPB %ld: %u\n", di_blockno_parent,
1194                       *total_remaining_blocks);
1195
1196                 status = ext4fs_devread(di_blockno_parent *
1197                                         fs->sect_perblk, 0,
1198                                         fs->blksz, (char *)di_parent_buffer);
1199
1200                 if (!status) {
1201                         printf("%s: Device read error!\n", __func__);
1202                         goto fail;
1203                 }
1204                 memset(di_parent_buffer, '\0', fs->blksz);
1205
1206                 /*
1207                  * start:for each double indirect parent
1208                  * block create one more block
1209                  */
1210                 for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
1211                         di_blockno_child = ext4fs_get_new_blk_no();
1212                         if (di_blockno_child == -1) {
1213                                 printf("no block left to assign\n");
1214                                 goto fail;
1215                         }
1216                         di_child_buff = zalloc(fs->blksz);
1217                         if (!di_child_buff)
1218                                 goto fail;
1219
1220                         di_child_buff_start = di_child_buff;
1221                         *di_parent_buffer = di_blockno_child;
1222                         di_parent_buffer++;
1223                         (*no_blks_reqd)++;
1224                         debug("DICB %ld: %u\n", di_blockno_child,
1225                               *total_remaining_blocks);
1226
1227                         status = ext4fs_devread(di_blockno_child *
1228                                                 fs->sect_perblk, 0,
1229                                                 fs->blksz,
1230                                                 (char *)di_child_buff);
1231
1232                         if (!status) {
1233                                 printf("%s: Device read error!\n", __func__);
1234                                 goto fail;
1235                         }
1236                         memset(di_child_buff, '\0', fs->blksz);
1237                         /* filling of actual datablocks for each child */
1238                         for (j = 0; j < (fs->blksz / sizeof(int)); j++) {
1239                                 actual_block_no = ext4fs_get_new_blk_no();
1240                                 if (actual_block_no == -1) {
1241                                         printf("no block left to assign\n");
1242                                         goto fail;
1243                                 }
1244                                 *di_child_buff = actual_block_no;
1245                                 debug("DIAB %ld: %u\n", actual_block_no,
1246                                       *total_remaining_blocks);
1247
1248                                 di_child_buff++;
1249                                 (*total_remaining_blocks)--;
1250                                 if (*total_remaining_blocks == 0)
1251                                         break;
1252                         }
1253                         /* write the block  table */
1254                         put_ext4(((uint64_t) (di_blockno_child * fs->blksz)),
1255                                  di_child_buff_start, fs->blksz);
1256                         free(di_child_buff_start);
1257                         di_child_buff_start = NULL;
1258
1259                         if (*total_remaining_blocks == 0)
1260                                 break;
1261                 }
1262                 put_ext4(((uint64_t) (di_blockno_parent * fs->blksz)),
1263                          di_block_start_addr, fs->blksz);
1264                 file_inode->b.blocks.double_indir_block = di_blockno_parent;
1265         }
1266 fail:
1267         free(di_block_start_addr);
1268 }
1269
1270 static void alloc_triple_indirect_block(struct ext2_inode *file_inode,
1271                                         unsigned int *total_remaining_blocks,
1272                                         unsigned int *no_blks_reqd)
1273 {
1274         short i;
1275         short j;
1276         short k;
1277         long int actual_block_no;
1278         /* ti: Triple Indirect */
1279         long int ti_gp_blockno;
1280         long int ti_parent_blockno;
1281         long int ti_child_blockno;
1282         unsigned int *ti_gp_buff = NULL;
1283         unsigned int *ti_parent_buff = NULL;
1284         unsigned int *ti_child_buff = NULL;
1285         unsigned int *ti_gp_buff_start_addr = NULL;
1286         unsigned int *ti_pbuff_start_addr = NULL;
1287         unsigned int *ti_cbuff_start_addr = NULL;
1288         struct ext_filesystem *fs = get_fs();
1289         if (*total_remaining_blocks != 0) {
1290                 /* triple indirect grand parent block connecting to inode */
1291                 ti_gp_blockno = ext4fs_get_new_blk_no();
1292                 if (ti_gp_blockno == -1) {
1293                         printf("no block left to assign\n");
1294                         goto fail;
1295                 }
1296                 ti_gp_buff = zalloc(fs->blksz);
1297                 if (!ti_gp_buff)
1298                         goto fail;
1299
1300                 ti_gp_buff_start_addr = ti_gp_buff;
1301                 (*no_blks_reqd)++;
1302                 debug("TIGPB %ld: %u\n", ti_gp_blockno,
1303                       *total_remaining_blocks);
1304
1305                 /* for each 4 byte grand parent entry create one more block */
1306                 for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
1307                         ti_parent_blockno = ext4fs_get_new_blk_no();
1308                         if (ti_parent_blockno == -1) {
1309                                 printf("no block left to assign\n");
1310                                 goto fail;
1311                         }
1312                         ti_parent_buff = zalloc(fs->blksz);
1313                         if (!ti_parent_buff)
1314                                 goto fail;
1315
1316                         ti_pbuff_start_addr = ti_parent_buff;
1317                         *ti_gp_buff = ti_parent_blockno;
1318                         ti_gp_buff++;
1319                         (*no_blks_reqd)++;
1320                         debug("TIPB %ld: %u\n", ti_parent_blockno,
1321                               *total_remaining_blocks);
1322
1323                         /* for each 4 byte entry parent create one more block */
1324                         for (j = 0; j < (fs->blksz / sizeof(int)); j++) {
1325                                 ti_child_blockno = ext4fs_get_new_blk_no();
1326                                 if (ti_child_blockno == -1) {
1327                                         printf("no block left assign\n");
1328                                         goto fail;
1329                                 }
1330                                 ti_child_buff = zalloc(fs->blksz);
1331                                 if (!ti_child_buff)
1332                                         goto fail;
1333
1334                                 ti_cbuff_start_addr = ti_child_buff;
1335                                 *ti_parent_buff = ti_child_blockno;
1336                                 ti_parent_buff++;
1337                                 (*no_blks_reqd)++;
1338                                 debug("TICB %ld: %u\n", ti_parent_blockno,
1339                                       *total_remaining_blocks);
1340
1341                                 /* fill actual datablocks for each child */
1342                                 for (k = 0; k < (fs->blksz / sizeof(int));
1343                                         k++) {
1344                                         actual_block_no =
1345                                             ext4fs_get_new_blk_no();
1346                                         if (actual_block_no == -1) {
1347                                                 printf("no block left\n");
1348                                                 goto fail;
1349                                         }
1350                                         *ti_child_buff = actual_block_no;
1351                                         debug("TIAB %ld: %u\n", actual_block_no,
1352                                               *total_remaining_blocks);
1353
1354                                         ti_child_buff++;
1355                                         (*total_remaining_blocks)--;
1356                                         if (*total_remaining_blocks == 0)
1357                                                 break;
1358                                 }
1359                                 /* write the child block */
1360                                 put_ext4(((uint64_t) (ti_child_blockno *
1361                                                       fs->blksz)),
1362                                          ti_cbuff_start_addr, fs->blksz);
1363                                 free(ti_cbuff_start_addr);
1364
1365                                 if (*total_remaining_blocks == 0)
1366                                         break;
1367                         }
1368                         /* write the parent block */
1369                         put_ext4(((uint64_t) (ti_parent_blockno * fs->blksz)),
1370                                  ti_pbuff_start_addr, fs->blksz);
1371                         free(ti_pbuff_start_addr);
1372
1373                         if (*total_remaining_blocks == 0)
1374                                 break;
1375                 }
1376                 /* write the grand parent block */
1377                 put_ext4(((uint64_t) (ti_gp_blockno * fs->blksz)),
1378                          ti_gp_buff_start_addr, fs->blksz);
1379                 file_inode->b.blocks.triple_indir_block = ti_gp_blockno;
1380         }
1381 fail:
1382         free(ti_gp_buff_start_addr);
1383 }
1384
1385 void ext4fs_allocate_blocks(struct ext2_inode *file_inode,
1386                                 unsigned int total_remaining_blocks,
1387                                 unsigned int *total_no_of_block)
1388 {
1389         short i;
1390         long int direct_blockno;
1391         unsigned int no_blks_reqd = 0;
1392
1393         /* allocation of direct blocks */
1394         for (i = 0; i < INDIRECT_BLOCKS; i++) {
1395                 direct_blockno = ext4fs_get_new_blk_no();
1396                 if (direct_blockno == -1) {
1397                         printf("no block left to assign\n");
1398                         return;
1399                 }
1400                 file_inode->b.blocks.dir_blocks[i] = direct_blockno;
1401                 debug("DB %ld: %u\n", direct_blockno, total_remaining_blocks);
1402
1403                 total_remaining_blocks--;
1404                 if (total_remaining_blocks == 0)
1405                         break;
1406         }
1407
1408         alloc_single_indirect_block(file_inode, &total_remaining_blocks,
1409                                     &no_blks_reqd);
1410         alloc_double_indirect_block(file_inode, &total_remaining_blocks,
1411                                     &no_blks_reqd);
1412         alloc_triple_indirect_block(file_inode, &total_remaining_blocks,
1413                                     &no_blks_reqd);
1414         *total_no_of_block += no_blks_reqd;
1415 }
1416
1417 #endif
1418
1419 static struct ext4_extent_header *ext4fs_get_extent_block
1420         (struct ext2_data *data, char *buf,
1421                 struct ext4_extent_header *ext_block,
1422                 uint32_t fileblock, int log2_blksz)
1423 {
1424         struct ext4_extent_idx *index;
1425         unsigned long long block;
1426         struct ext_filesystem *fs = get_fs();
1427         int i;
1428
1429         while (1) {
1430                 index = (struct ext4_extent_idx *)(ext_block + 1);
1431
1432                 if (le32_to_cpu(ext_block->eh_magic) != EXT4_EXT_MAGIC)
1433                         return 0;
1434
1435                 if (ext_block->eh_depth == 0)
1436                         return ext_block;
1437                 i = -1;
1438                 do {
1439                         i++;
1440                         if (i >= le32_to_cpu(ext_block->eh_entries))
1441                                 break;
1442                 } while (fileblock > le32_to_cpu(index[i].ei_block));
1443
1444                 if (--i < 0)
1445                         return 0;
1446
1447                 block = le32_to_cpu(index[i].ei_leaf_hi);
1448                 block = (block << 32) + le32_to_cpu(index[i].ei_leaf_lo);
1449
1450                 if (ext4fs_devread(block << log2_blksz, 0, fs->blksz, buf))
1451                         ext_block = (struct ext4_extent_header *)buf;
1452                 else
1453                         return 0;
1454         }
1455 }
1456
1457 static int ext4fs_blockgroup
1458         (struct ext2_data *data, int group, struct ext2_block_group *blkgrp)
1459 {
1460         long int blkno;
1461         unsigned int blkoff, desc_per_blk;
1462         int log2blksz = get_fs()->dev_desc->log2blksz;
1463
1464         desc_per_blk = EXT2_BLOCK_SIZE(data) / sizeof(struct ext2_block_group);
1465
1466         blkno = __le32_to_cpu(data->sblock.first_data_block) + 1 +
1467                         group / desc_per_blk;
1468         blkoff = (group % desc_per_blk) * sizeof(struct ext2_block_group);
1469
1470         debug("ext4fs read %d group descriptor (blkno %ld blkoff %u)\n",
1471               group, blkno, blkoff);
1472
1473         return ext4fs_devread(blkno << (LOG2_BLOCK_SIZE(data) - log2blksz),
1474                               blkoff, sizeof(struct ext2_block_group),
1475                               (char *)blkgrp);
1476 }
1477
1478 int ext4fs_read_inode(struct ext2_data *data, int ino, struct ext2_inode *inode)
1479 {
1480         struct ext2_block_group blkgrp;
1481         struct ext2_sblock *sblock = &data->sblock;
1482         struct ext_filesystem *fs = get_fs();
1483         int log2blksz = get_fs()->dev_desc->log2blksz;
1484         int inodes_per_block, status;
1485         long int blkno;
1486         unsigned int blkoff;
1487
1488         /* It is easier to calculate if the first inode is 0. */
1489         ino--;
1490         status = ext4fs_blockgroup(data, ino / __le32_to_cpu
1491                                    (sblock->inodes_per_group), &blkgrp);
1492         if (status == 0)
1493                 return 0;
1494
1495         inodes_per_block = EXT2_BLOCK_SIZE(data) / fs->inodesz;
1496         blkno = __le32_to_cpu(blkgrp.inode_table_id) +
1497             (ino % __le32_to_cpu(sblock->inodes_per_group)) / inodes_per_block;
1498         blkoff = (ino % inodes_per_block) * fs->inodesz;
1499         /* Read the inode. */
1500         status = ext4fs_devread(blkno << (LOG2_BLOCK_SIZE(data) - log2blksz),
1501                                 blkoff,
1502                                 sizeof(struct ext2_inode), (char *)inode);
1503         if (status == 0)
1504                 return 0;
1505
1506         return 1;
1507 }
1508
1509 long int read_allocated_block(struct ext2_inode *inode, int fileblock)
1510 {
1511         long int blknr;
1512         int blksz;
1513         int log2_blksz;
1514         int status;
1515         long int rblock;
1516         long int perblock_parent;
1517         long int perblock_child;
1518         unsigned long long start;
1519         /* get the blocksize of the filesystem */
1520         blksz = EXT2_BLOCK_SIZE(ext4fs_root);
1521         log2_blksz = LOG2_BLOCK_SIZE(ext4fs_root)
1522                 - get_fs()->dev_desc->log2blksz;
1523
1524         if (le32_to_cpu(inode->flags) & EXT4_EXTENTS_FL) {
1525                 char *buf = zalloc(blksz);
1526                 if (!buf)
1527                         return -ENOMEM;
1528                 struct ext4_extent_header *ext_block;
1529                 struct ext4_extent *extent;
1530                 int i = -1;
1531                 ext_block =
1532                         ext4fs_get_extent_block(ext4fs_root, buf,
1533                                                 (struct ext4_extent_header *)
1534                                                 inode->b.blocks.dir_blocks,
1535                                                 fileblock, log2_blksz);
1536                 if (!ext_block) {
1537                         printf("invalid extent block\n");
1538                         free(buf);
1539                         return -EINVAL;
1540                 }
1541
1542                 extent = (struct ext4_extent *)(ext_block + 1);
1543
1544                 do {
1545                         i++;
1546                         if (i >= le32_to_cpu(ext_block->eh_entries))
1547                                 break;
1548                 } while (fileblock >= le32_to_cpu(extent[i].ee_block));
1549                 if (--i >= 0) {
1550                         fileblock -= le32_to_cpu(extent[i].ee_block);
1551                         if (fileblock >= le32_to_cpu(extent[i].ee_len)) {
1552                                 free(buf);
1553                                 return 0;
1554                         }
1555
1556                         start = le32_to_cpu(extent[i].ee_start_hi);
1557                         start = (start << 32) +
1558                                         le32_to_cpu(extent[i].ee_start_lo);
1559                         free(buf);
1560                         return fileblock + start;
1561                 }
1562
1563                 printf("Extent Error\n");
1564                 free(buf);
1565                 return -1;
1566         }
1567
1568         /* Direct blocks. */
1569         if (fileblock < INDIRECT_BLOCKS)
1570                 blknr = __le32_to_cpu(inode->b.blocks.dir_blocks[fileblock]);
1571
1572         /* Indirect. */
1573         else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4))) {
1574                 if (ext4fs_indir1_block == NULL) {
1575                         ext4fs_indir1_block = zalloc(blksz);
1576                         if (ext4fs_indir1_block == NULL) {
1577                                 printf("** SI ext2fs read block (indir 1)"
1578                                         "malloc failed. **\n");
1579                                 return -1;
1580                         }
1581                         ext4fs_indir1_size = blksz;
1582                         ext4fs_indir1_blkno = -1;
1583                 }
1584                 if (blksz != ext4fs_indir1_size) {
1585                         free(ext4fs_indir1_block);
1586                         ext4fs_indir1_block = NULL;
1587                         ext4fs_indir1_size = 0;
1588                         ext4fs_indir1_blkno = -1;
1589                         ext4fs_indir1_block = zalloc(blksz);
1590                         if (ext4fs_indir1_block == NULL) {
1591                                 printf("** SI ext2fs read block (indir 1):"
1592                                         "malloc failed. **\n");
1593                                 return -1;
1594                         }
1595                         ext4fs_indir1_size = blksz;
1596                 }
1597                 if ((__le32_to_cpu(inode->b.blocks.indir_block) <<
1598                      log2_blksz) != ext4fs_indir1_blkno) {
1599                         status =
1600                             ext4fs_devread(__le32_to_cpu
1601                                            (inode->b.blocks.
1602                                             indir_block) << log2_blksz, 0,
1603                                            blksz, (char *)ext4fs_indir1_block);
1604                         if (status == 0) {
1605                                 printf("** SI ext2fs read block (indir 1)"
1606                                         "failed. **\n");
1607                                 return 0;
1608                         }
1609                         ext4fs_indir1_blkno =
1610                                 __le32_to_cpu(inode->b.blocks.
1611                                                indir_block) << log2_blksz;
1612                 }
1613                 blknr = __le32_to_cpu(ext4fs_indir1_block
1614                                       [fileblock - INDIRECT_BLOCKS]);
1615         }
1616         /* Double indirect. */
1617         else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4 *
1618                                         (blksz / 4 + 1)))) {
1619
1620                 long int perblock = blksz / 4;
1621                 long int rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4);
1622
1623                 if (ext4fs_indir1_block == NULL) {
1624                         ext4fs_indir1_block = zalloc(blksz);
1625                         if (ext4fs_indir1_block == NULL) {
1626                                 printf("** DI ext2fs read block (indir 2 1)"
1627                                         "malloc failed. **\n");
1628                                 return -1;
1629                         }
1630                         ext4fs_indir1_size = blksz;
1631                         ext4fs_indir1_blkno = -1;
1632                 }
1633                 if (blksz != ext4fs_indir1_size) {
1634                         free(ext4fs_indir1_block);
1635                         ext4fs_indir1_block = NULL;
1636                         ext4fs_indir1_size = 0;
1637                         ext4fs_indir1_blkno = -1;
1638                         ext4fs_indir1_block = zalloc(blksz);
1639                         if (ext4fs_indir1_block == NULL) {
1640                                 printf("** DI ext2fs read block (indir 2 1)"
1641                                         "malloc failed. **\n");
1642                                 return -1;
1643                         }
1644                         ext4fs_indir1_size = blksz;
1645                 }
1646                 if ((__le32_to_cpu(inode->b.blocks.double_indir_block) <<
1647                      log2_blksz) != ext4fs_indir1_blkno) {
1648                         status =
1649                             ext4fs_devread(__le32_to_cpu
1650                                            (inode->b.blocks.
1651                                             double_indir_block) << log2_blksz,
1652                                            0, blksz,
1653                                            (char *)ext4fs_indir1_block);
1654                         if (status == 0) {
1655                                 printf("** DI ext2fs read block (indir 2 1)"
1656                                         "failed. **\n");
1657                                 return -1;
1658                         }
1659                         ext4fs_indir1_blkno =
1660                             __le32_to_cpu(inode->b.blocks.double_indir_block) <<
1661                             log2_blksz;
1662                 }
1663
1664                 if (ext4fs_indir2_block == NULL) {
1665                         ext4fs_indir2_block = zalloc(blksz);
1666                         if (ext4fs_indir2_block == NULL) {
1667                                 printf("** DI ext2fs read block (indir 2 2)"
1668                                         "malloc failed. **\n");
1669                                 return -1;
1670                         }
1671                         ext4fs_indir2_size = blksz;
1672                         ext4fs_indir2_blkno = -1;
1673                 }
1674                 if (blksz != ext4fs_indir2_size) {
1675                         free(ext4fs_indir2_block);
1676                         ext4fs_indir2_block = NULL;
1677                         ext4fs_indir2_size = 0;
1678                         ext4fs_indir2_blkno = -1;
1679                         ext4fs_indir2_block = zalloc(blksz);
1680                         if (ext4fs_indir2_block == NULL) {
1681                                 printf("** DI ext2fs read block (indir 2 2)"
1682                                         "malloc failed. **\n");
1683                                 return -1;
1684                         }
1685                         ext4fs_indir2_size = blksz;
1686                 }
1687                 if ((__le32_to_cpu(ext4fs_indir1_block[rblock / perblock]) <<
1688                      log2_blksz) != ext4fs_indir2_blkno) {
1689                         status = ext4fs_devread(__le32_to_cpu
1690                                                 (ext4fs_indir1_block
1691                                                  [rblock /
1692                                                   perblock]) << log2_blksz, 0,
1693                                                 blksz,
1694                                                 (char *)ext4fs_indir2_block);
1695                         if (status == 0) {
1696                                 printf("** DI ext2fs read block (indir 2 2)"
1697                                         "failed. **\n");
1698                                 return -1;
1699                         }
1700                         ext4fs_indir2_blkno =
1701                             __le32_to_cpu(ext4fs_indir1_block[rblock
1702                                                               /
1703                                                               perblock]) <<
1704                             log2_blksz;
1705                 }
1706                 blknr = __le32_to_cpu(ext4fs_indir2_block[rblock % perblock]);
1707         }
1708         /* Tripple indirect. */
1709         else {
1710                 rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4 +
1711                                       (blksz / 4 * blksz / 4));
1712                 perblock_child = blksz / 4;
1713                 perblock_parent = ((blksz / 4) * (blksz / 4));
1714
1715                 if (ext4fs_indir1_block == NULL) {
1716                         ext4fs_indir1_block = zalloc(blksz);
1717                         if (ext4fs_indir1_block == NULL) {
1718                                 printf("** TI ext2fs read block (indir 2 1)"
1719                                         "malloc failed. **\n");
1720                                 return -1;
1721                         }
1722                         ext4fs_indir1_size = blksz;
1723                         ext4fs_indir1_blkno = -1;
1724                 }
1725                 if (blksz != ext4fs_indir1_size) {
1726                         free(ext4fs_indir1_block);
1727                         ext4fs_indir1_block = NULL;
1728                         ext4fs_indir1_size = 0;
1729                         ext4fs_indir1_blkno = -1;
1730                         ext4fs_indir1_block = zalloc(blksz);
1731                         if (ext4fs_indir1_block == NULL) {
1732                                 printf("** TI ext2fs read block (indir 2 1)"
1733                                         "malloc failed. **\n");
1734                                 return -1;
1735                         }
1736                         ext4fs_indir1_size = blksz;
1737                 }
1738                 if ((__le32_to_cpu(inode->b.blocks.triple_indir_block) <<
1739                      log2_blksz) != ext4fs_indir1_blkno) {
1740                         status = ext4fs_devread
1741                             (__le32_to_cpu(inode->b.blocks.triple_indir_block)
1742                              << log2_blksz, 0, blksz,
1743                              (char *)ext4fs_indir1_block);
1744                         if (status == 0) {
1745                                 printf("** TI ext2fs read block (indir 2 1)"
1746                                         "failed. **\n");
1747                                 return -1;
1748                         }
1749                         ext4fs_indir1_blkno =
1750                             __le32_to_cpu(inode->b.blocks.triple_indir_block) <<
1751                             log2_blksz;
1752                 }
1753
1754                 if (ext4fs_indir2_block == NULL) {
1755                         ext4fs_indir2_block = zalloc(blksz);
1756                         if (ext4fs_indir2_block == NULL) {
1757                                 printf("** TI ext2fs read block (indir 2 2)"
1758                                         "malloc failed. **\n");
1759                                 return -1;
1760                         }
1761                         ext4fs_indir2_size = blksz;
1762                         ext4fs_indir2_blkno = -1;
1763                 }
1764                 if (blksz != ext4fs_indir2_size) {
1765                         free(ext4fs_indir2_block);
1766                         ext4fs_indir2_block = NULL;
1767                         ext4fs_indir2_size = 0;
1768                         ext4fs_indir2_blkno = -1;
1769                         ext4fs_indir2_block = zalloc(blksz);
1770                         if (ext4fs_indir2_block == NULL) {
1771                                 printf("** TI ext2fs read block (indir 2 2)"
1772                                         "malloc failed. **\n");
1773                                 return -1;
1774                         }
1775                         ext4fs_indir2_size = blksz;
1776                 }
1777                 if ((__le32_to_cpu(ext4fs_indir1_block[rblock /
1778                                                        perblock_parent]) <<
1779                      log2_blksz)
1780                     != ext4fs_indir2_blkno) {
1781                         status = ext4fs_devread(__le32_to_cpu
1782                                                 (ext4fs_indir1_block
1783                                                  [rblock /
1784                                                   perblock_parent]) <<
1785                                                 log2_blksz, 0, blksz,
1786                                                 (char *)ext4fs_indir2_block);
1787                         if (status == 0) {
1788                                 printf("** TI ext2fs read block (indir 2 2)"
1789                                         "failed. **\n");
1790                                 return -1;
1791                         }
1792                         ext4fs_indir2_blkno =
1793                             __le32_to_cpu(ext4fs_indir1_block[rblock /
1794                                                               perblock_parent])
1795                             << log2_blksz;
1796                 }
1797
1798                 if (ext4fs_indir3_block == NULL) {
1799                         ext4fs_indir3_block = zalloc(blksz);
1800                         if (ext4fs_indir3_block == NULL) {
1801                                 printf("** TI ext2fs read block (indir 2 2)"
1802                                         "malloc failed. **\n");
1803                                 return -1;
1804                         }
1805                         ext4fs_indir3_size = blksz;
1806                         ext4fs_indir3_blkno = -1;
1807                 }
1808                 if (blksz != ext4fs_indir3_size) {
1809                         free(ext4fs_indir3_block);
1810                         ext4fs_indir3_block = NULL;
1811                         ext4fs_indir3_size = 0;
1812                         ext4fs_indir3_blkno = -1;
1813                         ext4fs_indir3_block = zalloc(blksz);
1814                         if (ext4fs_indir3_block == NULL) {
1815                                 printf("** TI ext2fs read block (indir 2 2)"
1816                                         "malloc failed. **\n");
1817                                 return -1;
1818                         }
1819                         ext4fs_indir3_size = blksz;
1820                 }
1821                 if ((__le32_to_cpu(ext4fs_indir2_block[rblock
1822                                                        /
1823                                                        perblock_child]) <<
1824                      log2_blksz) != ext4fs_indir3_blkno) {
1825                         status =
1826                             ext4fs_devread(__le32_to_cpu
1827                                            (ext4fs_indir2_block
1828                                             [(rblock / perblock_child)
1829                                              % (blksz / 4)]) << log2_blksz, 0,
1830                                            blksz, (char *)ext4fs_indir3_block);
1831                         if (status == 0) {
1832                                 printf("** TI ext2fs read block (indir 2 2)"
1833                                        "failed. **\n");
1834                                 return -1;
1835                         }
1836                         ext4fs_indir3_blkno =
1837                             __le32_to_cpu(ext4fs_indir2_block[(rblock /
1838                                                                perblock_child) %
1839                                                               (blksz /
1840                                                                4)]) <<
1841                             log2_blksz;
1842                 }
1843
1844                 blknr = __le32_to_cpu(ext4fs_indir3_block
1845                                       [rblock % perblock_child]);
1846         }
1847         debug("read_allocated_block %ld\n", blknr);
1848
1849         return blknr;
1850 }
1851
1852 void ext4fs_close(void)
1853 {
1854         if ((ext4fs_file != NULL) && (ext4fs_root != NULL)) {
1855                 ext4fs_free_node(ext4fs_file, &ext4fs_root->diropen);
1856                 ext4fs_file = NULL;
1857         }
1858         if (ext4fs_root != NULL) {
1859                 free(ext4fs_root);
1860                 ext4fs_root = NULL;
1861         }
1862         if (ext4fs_indir1_block != NULL) {
1863                 free(ext4fs_indir1_block);
1864                 ext4fs_indir1_block = NULL;
1865                 ext4fs_indir1_size = 0;
1866                 ext4fs_indir1_blkno = -1;
1867         }
1868         if (ext4fs_indir2_block != NULL) {
1869                 free(ext4fs_indir2_block);
1870                 ext4fs_indir2_block = NULL;
1871                 ext4fs_indir2_size = 0;
1872                 ext4fs_indir2_blkno = -1;
1873         }
1874         if (ext4fs_indir3_block != NULL) {
1875                 free(ext4fs_indir3_block);
1876                 ext4fs_indir3_block = NULL;
1877                 ext4fs_indir3_size = 0;
1878                 ext4fs_indir3_blkno = -1;
1879         }
1880 }
1881
1882 int ext4fs_iterate_dir(struct ext2fs_node *dir, char *name,
1883                                 struct ext2fs_node **fnode, int *ftype)
1884 {
1885         unsigned int fpos = 0;
1886         int status;
1887         struct ext2fs_node *diro = (struct ext2fs_node *) dir;
1888
1889 #ifdef DEBUG
1890         if (name != NULL)
1891                 printf("Iterate dir %s\n", name);
1892 #endif /* of DEBUG */
1893         if (!diro->inode_read) {
1894                 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode);
1895                 if (status == 0)
1896                         return 0;
1897         }
1898         /* Search the file.  */
1899         while (fpos < __le32_to_cpu(diro->inode.size)) {
1900                 struct ext2_dirent dirent;
1901
1902                 status = ext4fs_read_file(diro, fpos,
1903                                            sizeof(struct ext2_dirent),
1904                                            (char *) &dirent);
1905                 if (status < 1)
1906                         return 0;
1907
1908                 if (dirent.namelen != 0) {
1909                         char filename[dirent.namelen + 1];
1910                         struct ext2fs_node *fdiro;
1911                         int type = FILETYPE_UNKNOWN;
1912
1913                         status = ext4fs_read_file(diro,
1914                                                   fpos +
1915                                                   sizeof(struct ext2_dirent),
1916                                                   dirent.namelen, filename);
1917                         if (status < 1)
1918                                 return 0;
1919
1920                         fdiro = zalloc(sizeof(struct ext2fs_node));
1921                         if (!fdiro)
1922                                 return 0;
1923
1924                         fdiro->data = diro->data;
1925                         fdiro->ino = __le32_to_cpu(dirent.inode);
1926
1927                         filename[dirent.namelen] = '\0';
1928
1929                         if (dirent.filetype != FILETYPE_UNKNOWN) {
1930                                 fdiro->inode_read = 0;
1931
1932                                 if (dirent.filetype == FILETYPE_DIRECTORY)
1933                                         type = FILETYPE_DIRECTORY;
1934                                 else if (dirent.filetype == FILETYPE_SYMLINK)
1935                                         type = FILETYPE_SYMLINK;
1936                                 else if (dirent.filetype == FILETYPE_REG)
1937                                         type = FILETYPE_REG;
1938                         } else {
1939                                 status = ext4fs_read_inode(diro->data,
1940                                                            __le32_to_cpu
1941                                                            (dirent.inode),
1942                                                            &fdiro->inode);
1943                                 if (status == 0) {
1944                                         free(fdiro);
1945                                         return 0;
1946                                 }
1947                                 fdiro->inode_read = 1;
1948
1949                                 if ((__le16_to_cpu(fdiro->inode.mode) &
1950                                      FILETYPE_INO_MASK) ==
1951                                     FILETYPE_INO_DIRECTORY) {
1952                                         type = FILETYPE_DIRECTORY;
1953                                 } else if ((__le16_to_cpu(fdiro->inode.mode)
1954                                             & FILETYPE_INO_MASK) ==
1955                                            FILETYPE_INO_SYMLINK) {
1956                                         type = FILETYPE_SYMLINK;
1957                                 } else if ((__le16_to_cpu(fdiro->inode.mode)
1958                                             & FILETYPE_INO_MASK) ==
1959                                            FILETYPE_INO_REG) {
1960                                         type = FILETYPE_REG;
1961                                 }
1962                         }
1963 #ifdef DEBUG
1964                         printf("iterate >%s<\n", filename);
1965 #endif /* of DEBUG */
1966                         if ((name != NULL) && (fnode != NULL)
1967                             && (ftype != NULL)) {
1968                                 if (strcmp(filename, name) == 0) {
1969                                         *ftype = type;
1970                                         *fnode = fdiro;
1971                                         return 1;
1972                                 }
1973                         } else {
1974                                 if (fdiro->inode_read == 0) {
1975                                         status = ext4fs_read_inode(diro->data,
1976                                                                  __le32_to_cpu(
1977                                                                  dirent.inode),
1978                                                                  &fdiro->inode);
1979                                         if (status == 0) {
1980                                                 free(fdiro);
1981                                                 return 0;
1982                                         }
1983                                         fdiro->inode_read = 1;
1984                                 }
1985                                 switch (type) {
1986                                 case FILETYPE_DIRECTORY:
1987                                         printf("<DIR> ");
1988                                         break;
1989                                 case FILETYPE_SYMLINK:
1990                                         printf("<SYM> ");
1991                                         break;
1992                                 case FILETYPE_REG:
1993                                         printf("      ");
1994                                         break;
1995                                 default:
1996                                         printf("< ? > ");
1997                                         break;
1998                                 }
1999                                 printf("%10d %s\n",
2000                                         __le32_to_cpu(fdiro->inode.size),
2001                                         filename);
2002                         }
2003                         free(fdiro);
2004                 }
2005                 fpos += __le16_to_cpu(dirent.direntlen);
2006         }
2007         return 0;
2008 }
2009
2010 static char *ext4fs_read_symlink(struct ext2fs_node *node)
2011 {
2012         char *symlink;
2013         struct ext2fs_node *diro = node;
2014         int status;
2015
2016         if (!diro->inode_read) {
2017                 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode);
2018                 if (status == 0)
2019                         return 0;
2020         }
2021         symlink = zalloc(__le32_to_cpu(diro->inode.size) + 1);
2022         if (!symlink)
2023                 return 0;
2024
2025         if (__le32_to_cpu(diro->inode.size) <= 60) {
2026                 strncpy(symlink, diro->inode.b.symlink,
2027                          __le32_to_cpu(diro->inode.size));
2028         } else {
2029                 status = ext4fs_read_file(diro, 0,
2030                                            __le32_to_cpu(diro->inode.size),
2031                                            symlink);
2032                 if (status == 0) {
2033                         free(symlink);
2034                         return 0;
2035                 }
2036         }
2037         symlink[__le32_to_cpu(diro->inode.size)] = '\0';
2038         return symlink;
2039 }
2040
2041 static int ext4fs_find_file1(const char *currpath,
2042                              struct ext2fs_node *currroot,
2043                              struct ext2fs_node **currfound, int *foundtype)
2044 {
2045         char fpath[strlen(currpath) + 1];
2046         char *name = fpath;
2047         char *next;
2048         int status;
2049         int type = FILETYPE_DIRECTORY;
2050         struct ext2fs_node *currnode = currroot;
2051         struct ext2fs_node *oldnode = currroot;
2052
2053         strncpy(fpath, currpath, strlen(currpath) + 1);
2054
2055         /* Remove all leading slashes. */
2056         while (*name == '/')
2057                 name++;
2058
2059         if (!*name) {
2060                 *currfound = currnode;
2061                 return 1;
2062         }
2063
2064         for (;;) {
2065                 int found;
2066
2067                 /* Extract the actual part from the pathname. */
2068                 next = strchr(name, '/');
2069                 if (next) {
2070                         /* Remove all leading slashes. */
2071                         while (*next == '/')
2072                                 *(next++) = '\0';
2073                 }
2074
2075                 if (type != FILETYPE_DIRECTORY) {
2076                         ext4fs_free_node(currnode, currroot);
2077                         return 0;
2078                 }
2079
2080                 oldnode = currnode;
2081
2082                 /* Iterate over the directory. */
2083                 found = ext4fs_iterate_dir(currnode, name, &currnode, &type);
2084                 if (found == 0)
2085                         return 0;
2086
2087                 if (found == -1)
2088                         break;
2089
2090                 /* Read in the symlink and follow it. */
2091                 if (type == FILETYPE_SYMLINK) {
2092                         char *symlink;
2093
2094                         /* Test if the symlink does not loop. */
2095                         if (++symlinknest == 8) {
2096                                 ext4fs_free_node(currnode, currroot);
2097                                 ext4fs_free_node(oldnode, currroot);
2098                                 return 0;
2099                         }
2100
2101                         symlink = ext4fs_read_symlink(currnode);
2102                         ext4fs_free_node(currnode, currroot);
2103
2104                         if (!symlink) {
2105                                 ext4fs_free_node(oldnode, currroot);
2106                                 return 0;
2107                         }
2108
2109                         debug("Got symlink >%s<\n", symlink);
2110
2111                         if (symlink[0] == '/') {
2112                                 ext4fs_free_node(oldnode, currroot);
2113                                 oldnode = &ext4fs_root->diropen;
2114                         }
2115
2116                         /* Lookup the node the symlink points to. */
2117                         status = ext4fs_find_file1(symlink, oldnode,
2118                                                     &currnode, &type);
2119
2120                         free(symlink);
2121
2122                         if (status == 0) {
2123                                 ext4fs_free_node(oldnode, currroot);
2124                                 return 0;
2125                         }
2126                 }
2127
2128                 ext4fs_free_node(oldnode, currroot);
2129
2130                 /* Found the node! */
2131                 if (!next || *next == '\0') {
2132                         *currfound = currnode;
2133                         *foundtype = type;
2134                         return 1;
2135                 }
2136                 name = next;
2137         }
2138         return -1;
2139 }
2140
2141 int ext4fs_find_file(const char *path, struct ext2fs_node *rootnode,
2142         struct ext2fs_node **foundnode, int expecttype)
2143 {
2144         int status;
2145         int foundtype = FILETYPE_DIRECTORY;
2146
2147         symlinknest = 0;
2148         if (!path)
2149                 return 0;
2150
2151         status = ext4fs_find_file1(path, rootnode, foundnode, &foundtype);
2152         if (status == 0)
2153                 return 0;
2154
2155         /* Check if the node that was found was of the expected type. */
2156         if ((expecttype == FILETYPE_REG) && (foundtype != expecttype))
2157                 return 0;
2158         else if ((expecttype == FILETYPE_DIRECTORY)
2159                    && (foundtype != expecttype))
2160                 return 0;
2161
2162         return 1;
2163 }
2164
2165 int ext4fs_open(const char *filename)
2166 {
2167         struct ext2fs_node *fdiro = NULL;
2168         int status;
2169         int len;
2170
2171         if (ext4fs_root == NULL)
2172                 return -1;
2173
2174         ext4fs_file = NULL;
2175         status = ext4fs_find_file(filename, &ext4fs_root->diropen, &fdiro,
2176                                   FILETYPE_REG);
2177         if (status == 0)
2178                 goto fail;
2179
2180         if (!fdiro->inode_read) {
2181                 status = ext4fs_read_inode(fdiro->data, fdiro->ino,
2182                                 &fdiro->inode);
2183                 if (status == 0)
2184                         goto fail;
2185         }
2186         len = __le32_to_cpu(fdiro->inode.size);
2187         ext4fs_file = fdiro;
2188
2189         return len;
2190 fail:
2191         ext4fs_free_node(fdiro, &ext4fs_root->diropen);
2192
2193         return -1;
2194 }
2195
2196 int ext4fs_mount(unsigned part_length)
2197 {
2198         struct ext2_data *data;
2199         int status;
2200         struct ext_filesystem *fs = get_fs();
2201         data = zalloc(SUPERBLOCK_SIZE);
2202         if (!data)
2203                 return 0;
2204
2205         /* Read the superblock. */
2206         status = ext4_read_superblock((char *)&data->sblock);
2207
2208         if (status == 0)
2209                 goto fail;
2210
2211         /* Make sure this is an ext2 filesystem. */
2212         if (__le16_to_cpu(data->sblock.magic) != EXT2_MAGIC)
2213                 goto fail;
2214
2215         if (__le32_to_cpu(data->sblock.revision_level == 0))
2216                 fs->inodesz = 128;
2217         else
2218                 fs->inodesz = __le16_to_cpu(data->sblock.inode_size);
2219
2220         debug("EXT2 rev %d, inode_size %d\n",
2221                __le32_to_cpu(data->sblock.revision_level), fs->inodesz);
2222
2223         data->diropen.data = data;
2224         data->diropen.ino = 2;
2225         data->diropen.inode_read = 1;
2226         data->inode = &data->diropen.inode;
2227
2228         status = ext4fs_read_inode(data, 2, data->inode);
2229         if (status == 0)
2230                 goto fail;
2231
2232         ext4fs_root = data;
2233
2234         return 1;
2235 fail:
2236         printf("Failed to mount ext2 filesystem...\n");
2237         free(data);
2238         ext4fs_root = NULL;
2239
2240         return 0;
2241 }