fs/ext4/ext4_common.c

   1 /*
   2  * (C) Copyright 2011 - 2012 Samsung Electronics
   3  * EXT4 filesystem implementation in Uboot by
   4  * Uma Shankar <uma.shankar@samsung.com>
   5  * Manjunatha C Achar <a.manjunatha@samsung.com>
   6  *
   7  * ext4ls and ext4load : Based on ext2 ls load support in Uboot.
   8  *
   9  * (C) Copyright 2004
  10  * esd gmbh <www.esd-electronics.com>
  11  * Reinhard Arlt <reinhard.arlt@esd-electronics.com>
  12  *
  13  * based on code from grub2 fs/ext2.c and fs/fshelp.c by
  14  * GRUB  --  GRand Unified Bootloader
  15  * Copyright (C) 2003, 2004  Free Software Foundation, Inc.
  16  *
  17  * ext4write : Based on generic ext4 protocol.
  18  *
  19  * SPDX-License-Identifier:     GPL-2.0+
  20  */
  21
  22 #include <common.h>
  23 #include <ext_common.h>
  24 #include <ext4fs.h>
  25 #include <inttypes.h>
  26 #include <malloc.h>
  27 #include <memalign.h>
  28 #include <stddef.h>
  29 #include <linux/stat.h>
  30 #include <linux/time.h>
  31 #include <asm/byteorder.h>
  32 #include "ext4_common.h"
  33
  34 struct ext2_data *ext4fs_root;
  35 struct ext2fs_node *ext4fs_file;
  36 __le32 *ext4fs_indir1_block;
  37 int ext4fs_indir1_size;
  38 int ext4fs_indir1_blkno = -1;
  39 __le32 *ext4fs_indir2_block;
  40 int ext4fs_indir2_size;
  41 int ext4fs_indir2_blkno = -1;
  42
  43 __le32 *ext4fs_indir3_block;
  44 int ext4fs_indir3_size;
  45 int ext4fs_indir3_blkno = -1;
  46 struct ext2_inode *g_parent_inode;
  47 static int symlinknest;
  48
  49 #if defined(CONFIG_EXT4_WRITE)
  50 static inline void ext4fs_sb_free_inodes_dec(struct ext2_sblock *sb)
  51 {
  52         sb->free_inodes = cpu_to_le32(le32_to_cpu(sb->free_inodes) - 1);
  53 }
  54
  55 static inline void ext4fs_sb_free_blocks_dec(struct ext2_sblock *sb)
  56 {
  57         sb->free_blocks = cpu_to_le32(le32_to_cpu(sb->free_blocks) - 1);
  58 }
  59
  60 static inline void ext4fs_bg_free_inodes_dec(struct ext2_block_group *bg)
  61 {
  62         bg->free_inodes = cpu_to_le16(le16_to_cpu(bg->free_inodes) - 1);
  63 }
  64
  65 static inline void ext4fs_bg_free_blocks_dec(struct ext2_block_group *bg)
  66 {
  67         bg->free_blocks = cpu_to_le16(le16_to_cpu(bg->free_blocks) - 1);
  68 }
  69
  70 static inline void ext4fs_bg_itable_unused_dec(struct ext2_block_group *bg)
  71 {
  72         bg->bg_itable_unused = cpu_to_le16(le16_to_cpu(bg->bg_itable_unused) - 1);
  73 }
  74
  75 uint32_t ext4fs_div_roundup(uint32_t size, uint32_t n)
  76 {
  77         uint32_t res = size / n;
  78         if (res * n != size)
  79                 res++;
  80
  81         return res;
  82 }
  83
  84 void put_ext4(uint64_t off, void *buf, uint32_t size)
  85 {
  86         uint64_t startblock;
  87         uint64_t remainder;
  88         unsigned char *temp_ptr = NULL;
  89         struct ext_filesystem *fs = get_fs();
  90         int log2blksz = fs->dev_desc->log2blksz;
  91         ALLOC_CACHE_ALIGN_BUFFER(unsigned char, sec_buf, fs->dev_desc->blksz);
  92
  93         startblock = off >> log2blksz;
  94         startblock += part_offset;
  95         remainder = off & (uint64_t)(fs->dev_desc->blksz - 1);
  96
  97         if (fs->dev_desc == NULL)
  98                 return;
  99
 100         if ((startblock + (size >> log2blksz)) >
 101             (part_offset + fs->total_sect)) {
 102                 printf("part_offset is " LBAFU "\n", part_offset);
 103                 printf("total_sector is %" PRIu64 "\n", fs->total_sect);
 104                 printf("error: overflow occurs\n");
 105                 return;
 106         }
 107
 108         if (remainder) {
 109                 blk_dread(fs->dev_desc, startblock, 1, sec_buf);
 110                 temp_ptr = sec_buf;
 111                 memcpy((temp_ptr + remainder), (unsigned char *)buf, size);
 112                 blk_dwrite(fs->dev_desc, startblock, 1, sec_buf);
 113         } else {
 114                 if (size >> log2blksz != 0) {
 115                         blk_dwrite(fs->dev_desc, startblock, size >> log2blksz,
 116                                    (unsigned long *)buf);
 117                 } else {
 118                         blk_dread(fs->dev_desc, startblock, 1, sec_buf);
 119                         temp_ptr = sec_buf;
 120                         memcpy(temp_ptr, buf, size);
 121                         blk_dwrite(fs->dev_desc, startblock, 1,
 122                                    (unsigned long *)sec_buf);
 123                 }
 124         }
 125 }
 126
 127 static int _get_new_inode_no(unsigned char *buffer)
 128 {
 129         struct ext_filesystem *fs = get_fs();
 130         unsigned char input;
 131         int operand, status;
 132         int count = 1;
 133         int j = 0;
 134
 135         /* get the blocksize of the filesystem */
 136         unsigned char *ptr = buffer;
 137         while (*ptr == 255) {
 138                 ptr++;
 139                 count += 8;
 140                 if (count > le32_to_cpu(ext4fs_root->sblock.inodes_per_group))
 141                         return -1;
 142         }
 143
 144         for (j = 0; j < fs->blksz; j++) {
 145                 input = *ptr;
 146                 int i = 0;
 147                 while (i <= 7) {
 148                         operand = 1 << i;
 149                         status = input & operand;
 150                         if (status) {
 151                                 i++;
 152                                 count++;
 153                         } else {
 154                                 *ptr |= operand;
 155                                 return count;
 156                         }
 157                 }
 158                 ptr = ptr + 1;
 159         }
 160
 161         return -1;
 162 }
 163
 164 static int _get_new_blk_no(unsigned char *buffer)
 165 {
 166         unsigned char input;
 167         int operand, status;
 168         int count = 0;
 169         int j = 0;
 170         unsigned char *ptr = buffer;
 171         struct ext_filesystem *fs = get_fs();
 172
 173         if (fs->blksz != 1024)
 174                 count = 0;
 175         else
 176                 count = 1;
 177
 178         while (*ptr == 255) {
 179                 ptr++;
 180                 count += 8;
 181                 if (count == (fs->blksz * 8))
 182                         return -1;
 183         }
 184
 185         for (j = 0; j < fs->blksz; j++) {
 186                 input = *ptr;
 187                 int i = 0;
 188                 while (i <= 7) {
 189                         operand = 1 << i;
 190                         status = input & operand;
 191                         if (status) {
 192                                 i++;
 193                                 count++;
 194                         } else {
 195                                 *ptr |= operand;
 196                                 return count;
 197                         }
 198                 }
 199                 ptr = ptr + 1;
 200         }
 201
 202         return -1;
 203 }
 204
 205 int ext4fs_set_block_bmap(long int blockno, unsigned char *buffer, int index)
 206 {
 207         int i, remainder, status;
 208         unsigned char *ptr = buffer;
 209         unsigned char operand;
 210         i = blockno / 8;
 211         remainder = blockno % 8;
 212         int blocksize = EXT2_BLOCK_SIZE(ext4fs_root);
 213
 214         i = i - (index * blocksize);
 215         if (blocksize != 1024) {
 216                 ptr = ptr + i;
 217                 operand = 1 << remainder;
 218                 status = *ptr & operand;
 219                 if (status)
 220                         return -1;
 221
 222                 *ptr = *ptr | operand;
 223                 return 0;
 224         } else {
 225                 if (remainder == 0) {
 226                         ptr = ptr + i - 1;
 227                         operand = (1 << 7);
 228                 } else {
 229                         ptr = ptr + i;
 230                         operand = (1 << (remainder - 1));
 231                 }
 232                 status = *ptr & operand;
 233                 if (status)
 234                         return -1;
 235
 236                 *ptr = *ptr | operand;
 237                 return 0;
 238         }
 239 }
 240
 241 void ext4fs_reset_block_bmap(long int blockno, unsigned char *buffer, int index)
 242 {
 243         int i, remainder, status;
 244         unsigned char *ptr = buffer;
 245         unsigned char operand;
 246         i = blockno / 8;
 247         remainder = blockno % 8;
 248         int blocksize = EXT2_BLOCK_SIZE(ext4fs_root);
 249
 250         i = i - (index * blocksize);
 251         if (blocksize != 1024) {
 252                 ptr = ptr + i;
 253                 operand = (1 << remainder);
 254                 status = *ptr & operand;
 255                 if (status)
 256                         *ptr = *ptr & ~(operand);
 257         } else {
 258                 if (remainder == 0) {
 259                         ptr = ptr + i - 1;
 260                         operand = (1 << 7);
 261                 } else {
 262                         ptr = ptr + i;
 263                         operand = (1 << (remainder - 1));
 264                 }
 265                 status = *ptr & operand;
 266                 if (status)
 267                         *ptr = *ptr & ~(operand);
 268         }
 269 }
 270
 271 int ext4fs_set_inode_bmap(int inode_no, unsigned char *buffer, int index)
 272 {
 273         int i, remainder, status;
 274         unsigned char *ptr = buffer;
 275         unsigned char operand;
 276
 277         inode_no -= (index * le32_to_cpu(ext4fs_root->sblock.inodes_per_group));
 278         i = inode_no / 8;
 279         remainder = inode_no % 8;
 280         if (remainder == 0) {
 281                 ptr = ptr + i - 1;
 282                 operand = (1 << 7);
 283         } else {
 284                 ptr = ptr + i;
 285                 operand = (1 << (remainder - 1));
 286         }
 287         status = *ptr & operand;
 288         if (status)
 289                 return -1;
 290
 291         *ptr = *ptr | operand;
 292
 293         return 0;
 294 }
 295
 296 void ext4fs_reset_inode_bmap(int inode_no, unsigned char *buffer, int index)
 297 {
 298         int i, remainder, status;
 299         unsigned char *ptr = buffer;
 300         unsigned char operand;
 301
 302         inode_no -= (index * le32_to_cpu(ext4fs_root->sblock.inodes_per_group));
 303         i = inode_no / 8;
 304         remainder = inode_no % 8;
 305         if (remainder == 0) {
 306                 ptr = ptr + i - 1;
 307                 operand = (1 << 7);
 308         } else {
 309                 ptr = ptr + i;
 310                 operand = (1 << (remainder - 1));
 311         }
 312         status = *ptr & operand;
 313         if (status)
 314                 *ptr = *ptr & ~(operand);
 315 }
 316
 317 uint16_t ext4fs_checksum_update(uint32_t i)
 318 {
 319         struct ext2_block_group *desc;
 320         struct ext_filesystem *fs = get_fs();
 321         uint16_t crc = 0;
 322         __le32 le32_i = cpu_to_le32(i);
 323
 324         desc = (struct ext2_block_group *)&fs->bgd[i];
 325         if (le32_to_cpu(fs->sb->feature_ro_compat) & EXT4_FEATURE_RO_COMPAT_GDT_CSUM) {
 326                 int offset = offsetof(struct ext2_block_group, bg_checksum);
 327
 328                 crc = ext2fs_crc16(~0, fs->sb->unique_id,
 329                                    sizeof(fs->sb->unique_id));
 330                 crc = ext2fs_crc16(crc, &le32_i, sizeof(le32_i));
 331                 crc = ext2fs_crc16(crc, desc, offset);
 332                 offset += sizeof(desc->bg_checksum);    /* skip checksum */
 333                 assert(offset == sizeof(*desc));
 334         }
 335
 336         return crc;
 337 }
 338
 339 static int check_void_in_dentry(struct ext2_dirent *dir, char *filename)
 340 {
 341         int dentry_length;
 342         int sizeof_void_space;
 343         int new_entry_byte_reqd;
 344         short padding_factor = 0;
 345
 346         if (dir->namelen % 4 != 0)
 347                 padding_factor = 4 - (dir->namelen % 4);
 348
 349         dentry_length = sizeof(struct ext2_dirent) +
 350                         dir->namelen + padding_factor;
 351         sizeof_void_space = le16_to_cpu(dir->direntlen) - dentry_length;
 352         if (sizeof_void_space == 0)
 353                 return 0;
 354
 355         padding_factor = 0;
 356         if (strlen(filename) % 4 != 0)
 357                 padding_factor = 4 - (strlen(filename) % 4);
 358
 359         new_entry_byte_reqd = strlen(filename) +
 360             sizeof(struct ext2_dirent) + padding_factor;
 361         if (sizeof_void_space >= new_entry_byte_reqd) {
 362                 dir->direntlen = cpu_to_le16(dentry_length);
 363                 return sizeof_void_space;
 364         }
 365
 366         return 0;
 367 }
 368
 369 int ext4fs_update_parent_dentry(char *filename, int file_type)
 370 {
 371         unsigned int *zero_buffer = NULL;
 372         char *root_first_block_buffer = NULL;
 373         int direct_blk_idx;
 374         long int root_blknr;
 375         long int first_block_no_of_root = 0;
 376         long int previous_blknr = -1;
 377         int totalbytes = 0;
 378         short int padding_factor = 0;
 379         unsigned int new_entry_byte_reqd;
 380         unsigned int last_entry_dirlen;
 381         int sizeof_void_space = 0;
 382         int templength = 0;
 383         int inodeno = -1;
 384         int status;
 385         struct ext_filesystem *fs = get_fs();
 386         /* directory entry */
 387         struct ext2_dirent *dir;
 388         char *temp_dir = NULL;
 389         uint32_t new_blk_no;
 390         uint32_t new_size;
 391         uint32_t new_blockcnt;
 392
 393         zero_buffer = zalloc(fs->blksz);
 394         if (!zero_buffer) {
 395                 printf("No Memory\n");
 396                 return -1;
 397         }
 398         root_first_block_buffer = zalloc(fs->blksz);
 399         if (!root_first_block_buffer) {
 400                 free(zero_buffer);
 401                 printf("No Memory\n");
 402                 return -1;
 403         }
 404 restart:
 405
 406         /* read the block no allocated to a file */
 407         for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS;
 408              direct_blk_idx++) {
 409                 root_blknr = read_allocated_block(g_parent_inode,
 410                                                   direct_blk_idx);
 411                 if (root_blknr == 0) {
 412                         first_block_no_of_root = previous_blknr;
 413                         break;
 414                 }
 415                 previous_blknr = root_blknr;
 416         }
 417
 418         status = ext4fs_devread((lbaint_t)first_block_no_of_root
 419                                 * fs->sect_perblk,
 420                                 0, fs->blksz, root_first_block_buffer);
 421         if (status == 0)
 422                 goto fail;
 423
 424         if (ext4fs_log_journal(root_first_block_buffer, first_block_no_of_root))
 425                 goto fail;
 426         dir = (struct ext2_dirent *)root_first_block_buffer;
 427         totalbytes = 0;
 428         while (le16_to_cpu(dir->direntlen) > 0) {
 429                 /*
 430                  * blocksize-totalbytes because last directory length
 431                  * i.e. dir->direntlen is free availble space in the
 432                  * block that means  it is a last entry of directory
 433                  * entry
 434                  */
 435
 436                 /* traversing the each directory entry */
 437                 if (fs->blksz - totalbytes == le16_to_cpu(dir->direntlen)) {
 438                         if (strlen(filename) % 4 != 0)
 439                                 padding_factor = 4 - (strlen(filename) % 4);
 440
 441                         new_entry_byte_reqd = strlen(filename) +
 442                             sizeof(struct ext2_dirent) + padding_factor;
 443                         padding_factor = 0;
 444                         /*
 445                          * update last directory entry length to its
 446                          * length because we are creating new directory
 447                          * entry
 448                          */
 449                         if (dir->namelen % 4 != 0)
 450                                 padding_factor = 4 - (dir->namelen % 4);
 451
 452                         last_entry_dirlen = dir->namelen +
 453                             sizeof(struct ext2_dirent) + padding_factor;
 454                         if ((fs->blksz - totalbytes - last_entry_dirlen) <
 455                                 new_entry_byte_reqd) {
 456                                 printf("1st Block Full:Allocate new block\n");
 457
 458                                 if (direct_blk_idx == INDIRECT_BLOCKS - 1) {
 459                                         printf("Directory exceeds limit\n");
 460                                         goto fail;
 461                                 }
 462                                 new_blk_no = ext4fs_get_new_blk_no();
 463                                 if (new_blk_no == -1) {
 464                                         printf("no block left to assign\n");
 465                                         goto fail;
 466                                 }
 467                                 put_ext4((uint64_t)new_blk_no * fs->blksz, zero_buffer, fs->blksz);
 468                                 g_parent_inode->b.blocks.dir_blocks[direct_blk_idx] =
 469                                         cpu_to_le32(new_blk_no);
 470
 471                                 new_size = le32_to_cpu(g_parent_inode->size);
 472                                 new_size += fs->blksz;
 473                                 g_parent_inode->size = cpu_to_le32(new_size);
 474
 475                                 new_blockcnt = le32_to_cpu(g_parent_inode->blockcnt);
 476                                 new_blockcnt += fs->sect_perblk;
 477                                 g_parent_inode->blockcnt = cpu_to_le32(new_blockcnt);
 478
 479                                 if (ext4fs_put_metadata
 480                                     (root_first_block_buffer,
 481                                      first_block_no_of_root))
 482                                         goto fail;
 483                                 goto restart;
 484                         }
 485                         dir->direntlen = cpu_to_le16(last_entry_dirlen);
 486                         break;
 487                 }
 488
 489                 templength = le16_to_cpu(dir->direntlen);
 490                 totalbytes = totalbytes + templength;
 491                 sizeof_void_space = check_void_in_dentry(dir, filename);
 492                 if (sizeof_void_space)
 493                         break;
 494
 495                 dir = (struct ext2_dirent *)((char *)dir + templength);
 496         }
 497
 498         /* make a pointer ready for creating next directory entry */
 499         templength = le16_to_cpu(dir->direntlen);
 500         totalbytes = totalbytes + templength;
 501         dir = (struct ext2_dirent *)((char *)dir + templength);
 502
 503         /* get the next available inode number */
 504         inodeno = ext4fs_get_new_inode_no();
 505         if (inodeno == -1) {
 506                 printf("no inode left to assign\n");
 507                 goto fail;
 508         }
 509         dir->inode = cpu_to_le32(inodeno);
 510         if (sizeof_void_space)
 511                 dir->direntlen = cpu_to_le16(sizeof_void_space);
 512         else
 513                 dir->direntlen = cpu_to_le16(fs->blksz - totalbytes);
 514
 515         dir->namelen = strlen(filename);
 516         dir->filetype = FILETYPE_REG;   /* regular file */
 517         temp_dir = (char *)dir;
 518         temp_dir = temp_dir + sizeof(struct ext2_dirent);
 519         memcpy(temp_dir, filename, strlen(filename));
 520
 521         /* update or write  the 1st block of root inode */
 522         if (ext4fs_put_metadata(root_first_block_buffer,
 523                                 first_block_no_of_root))
 524                 goto fail;
 525
 526 fail:
 527         free(zero_buffer);
 528         free(root_first_block_buffer);
 529
 530         return inodeno;
 531 }
 532
 533 static int search_dir(struct ext2_inode *parent_inode, char *dirname)
 534 {
 535         int status;
 536         int inodeno = 0;
 537         int totalbytes;
 538         int templength;
 539         int direct_blk_idx;
 540         long int blknr;
 541         char *ptr = NULL;
 542         unsigned char *block_buffer = NULL;
 543         struct ext2_dirent *dir = NULL;
 544         struct ext_filesystem *fs = get_fs();
 545
 546         /* read the block no allocated to a file */
 547         for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS;
 548                 direct_blk_idx++) {
 549                 blknr = read_allocated_block(parent_inode, direct_blk_idx);
 550                 if (blknr == 0)
 551                         goto fail;
 552
 553                 /* read the blocks of parent inode */
 554                 block_buffer = zalloc(fs->blksz);
 555                 if (!block_buffer)
 556                         goto fail;
 557
 558                 status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk,
 559                                         0, fs->blksz, (char *)block_buffer);
 560                 if (status == 0)
 561                         goto fail;
 562
 563                 dir = (struct ext2_dirent *)block_buffer;
 564                 ptr = (char *)dir;
 565                 totalbytes = 0;
 566                 while (le16_to_cpu(dir->direntlen) >= 0) {
 567                         /*
 568                          * blocksize-totalbytes because last directory
 569                          * length i.e.,*dir->direntlen is free availble
 570                          * space in the block that means
 571                          * it is a last entry of directory entry
 572                          */
 573                         if (dir->inode && (strlen(dirname) == dir->namelen)) {
 574                                 if (strncmp(dirname, ptr + sizeof(struct ext2_dirent), dir->namelen) == 0) {
 575                                         inodeno = le32_to_cpu(dir->inode);
 576                                         break;
 577                                 }
 578                         }
 579
 580                         if (fs->blksz - totalbytes == le16_to_cpu(dir->direntlen))
 581                                 break;
 582
 583                         /* traversing the each directory entry */
 584                         templength = le16_to_cpu(dir->direntlen);
 585                         totalbytes = totalbytes + templength;
 586                         dir = (struct ext2_dirent *)((char *)dir + templength);
 587                         ptr = (char *)dir;
 588                 }
 589
 590                 free(block_buffer);
 591                 block_buffer = NULL;
 592
 593                 if (inodeno > 0)
 594                         return inodeno;
 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         memcpy(arr[i++], "/", strlen("/"));
 629
 630         /* add each path entry after root */
 631         while (token != NULL) {
 632                 arr[i] = zalloc(strlen(token) + 1);
 633                 if (!arr[i])
 634                         return -ENOMEM;
 635                 memcpy(arr[i++], token, strlen(token));
 636                 token = strtok(NULL, "/");
 637         }
 638         arr[i] = NULL;
 639
 640         return 0;
 641 }
 642
 643 int ext4fs_iget(int inode_no, struct ext2_inode *inode)
 644 {
 645         if (ext4fs_read_inode(ext4fs_root, inode_no, inode) == 0)
 646                 return -1;
 647
 648         return 0;
 649 }
 650
 651 /*
 652  * Function: ext4fs_get_parent_inode_num
 653  * Return Value: inode Number of the parent directory of  file/Directory to be
 654  * created
 655  * dirname : Input parmater, input path name of the file/directory to be created
 656  * dname : Output parameter, to be filled with the name of the directory
 657  * extracted from dirname
 658  */
 659 int ext4fs_get_parent_inode_num(const char *dirname, char *dname, int flags)
 660 {
 661         int i;
 662         int depth = 0;
 663         int matched_inode_no;
 664         int result_inode_no = -1;
 665         char **ptr = NULL;
 666         char *depth_dirname = NULL;
 667         char *parse_dirname = NULL;
 668         struct ext2_inode *parent_inode = NULL;
 669         struct ext2_inode *first_inode = NULL;
 670         struct ext2_inode temp_inode;
 671
 672         if (*dirname != '/') {
 673                 printf("Please supply Absolute path\n");
 674                 return -1;
 675         }
 676
 677         /* TODO: input validation make equivalent to linux */
 678         depth_dirname = zalloc(strlen(dirname) + 1);
 679         if (!depth_dirname)
 680                 return -ENOMEM;
 681
 682         memcpy(depth_dirname, dirname, strlen(dirname));
 683         depth = find_dir_depth(depth_dirname);
 684         parse_dirname = zalloc(strlen(dirname) + 1);
 685         if (!parse_dirname)
 686                 goto fail;
 687         memcpy(parse_dirname, dirname, strlen(dirname));
 688
 689         /* allocate memory for each directory level */
 690         ptr = zalloc((depth) * sizeof(char *));
 691         if (!ptr)
 692                 goto fail;
 693         if (parse_path(ptr, parse_dirname))
 694                 goto fail;
 695         parent_inode = zalloc(sizeof(struct ext2_inode));
 696         if (!parent_inode)
 697                 goto fail;
 698         first_inode = zalloc(sizeof(struct ext2_inode));
 699         if (!first_inode)
 700                 goto fail;
 701         memcpy(parent_inode, ext4fs_root->inode, sizeof(struct ext2_inode));
 702         memcpy(first_inode, parent_inode, sizeof(struct ext2_inode));
 703         if (flags & F_FILE)
 704                 result_inode_no = EXT2_ROOT_INO;
 705         for (i = 1; i < depth; i++) {
 706                 matched_inode_no = search_dir(parent_inode, ptr[i]);
 707                 if (matched_inode_no == -1) {
 708                         if (ptr[i + 1] == NULL && i == 1) {
 709                                 result_inode_no = EXT2_ROOT_INO;
 710                                 goto end;
 711                         } else {
 712                                 if (ptr[i + 1] == NULL)
 713                                         break;
 714                                 printf("Invalid path\n");
 715                                 result_inode_no = -1;
 716                                 goto fail;
 717                         }
 718                 } else {
 719                         if (ptr[i + 1] != NULL) {
 720                                 memset(parent_inode, '\0',
 721                                        sizeof(struct ext2_inode));
 722                                 if (ext4fs_iget(matched_inode_no,
 723                                                 parent_inode)) {
 724                                         result_inode_no = -1;
 725                                         goto fail;
 726                                 }
 727                                 result_inode_no = matched_inode_no;
 728                         } else {
 729                                 break;
 730                         }
 731                 }
 732         }
 733
 734 end:
 735         if (i == 1)
 736                 matched_inode_no = search_dir(first_inode, ptr[i]);
 737         else
 738                 matched_inode_no = search_dir(parent_inode, ptr[i]);
 739
 740         if (matched_inode_no != -1) {
 741                 ext4fs_iget(matched_inode_no, &temp_inode);
 742                 if (le16_to_cpu(temp_inode.mode) & S_IFDIR) {
 743                         printf("It is a Directory\n");
 744                         result_inode_no = -1;
 745                         goto fail;
 746                 }
 747         }
 748
 749         if (strlen(ptr[i]) > 256) {
 750                 result_inode_no = -1;
 751                 goto fail;
 752         }
 753         memcpy(dname, ptr[i], strlen(ptr[i]));
 754
 755 fail:
 756         free(depth_dirname);
 757         free(parse_dirname);
 758         for (i = 0; i < depth; i++) {
 759                 if (!ptr[i])
 760                         break;
 761                 free(ptr[i]);
 762         }
 763         free(ptr);
 764         free(parent_inode);
 765         free(first_inode);
 766
 767         return result_inode_no;
 768 }
 769
 770 static int unlink_filename(char *filename, unsigned int blknr)
 771 {
 772         int totalbytes = 0;
 773         int templength = 0;
 774         int status, inodeno;
 775         int found = 0;
 776         char *root_first_block_buffer = NULL;
 777         struct ext2_dirent *dir = NULL;
 778         struct ext2_dirent *previous_dir = NULL;
 779         char *ptr = NULL;
 780         struct ext_filesystem *fs = get_fs();
 781         int ret = -1;
 782
 783         /* get the first block of root */
 784         root_first_block_buffer = zalloc(fs->blksz);
 785         if (!root_first_block_buffer)
 786                 return -ENOMEM;
 787         status = ext4fs_devread((lbaint_t)blknr * 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, blknr))
 793                 goto fail;
 794         dir = (struct ext2_dirent *)root_first_block_buffer;
 795         ptr = (char *)dir;
 796         totalbytes = 0;
 797         while (le16_to_cpu(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 (dir->inode && (strlen(filename) == dir->namelen) &&
 805                     (strncmp(ptr + sizeof(struct ext2_dirent),
 806                              filename, dir->namelen) == 0)) {
 807                         printf("file found, deleting\n");
 808                         inodeno = le32_to_cpu(dir->inode);
 809                         if (previous_dir) {
 810                                 uint16_t new_len;
 811                                 new_len = le16_to_cpu(previous_dir->direntlen);
 812                                 new_len += le16_to_cpu(dir->direntlen);
 813                                 previous_dir->direntlen = cpu_to_le16(new_len);
 814                         } else {
 815                                 dir->inode = 0;
 816                         }
 817                         found = 1;
 818                         break;
 819                 }
 820
 821                 if (fs->blksz - totalbytes == le16_to_cpu(dir->direntlen))
 822                         break;
 823
 824                 /* traversing the each directory entry */
 825                 templength = le16_to_cpu(dir->direntlen);
 826                 totalbytes = totalbytes + templength;
 827                 previous_dir = dir;
 828                 dir = (struct ext2_dirent *)((char *)dir + templength);
 829                 ptr = (char *)dir;
 830         }
 831
 832
 833         if (found == 1) {
 834                 if (ext4fs_put_metadata(root_first_block_buffer, blknr))
 835                         goto fail;
 836                 ret = inodeno;
 837         }
 838 fail:
 839         free(root_first_block_buffer);
 840
 841         return ret;
 842 }
 843
 844 int ext4fs_filename_unlink(char *filename)
 845 {
 846         short direct_blk_idx = 0;
 847         long int blknr = -1;
 848         int inodeno = -1;
 849
 850         /* read the block no allocated to a file */
 851         for (direct_blk_idx = 0; direct_blk_idx < INDIRECT_BLOCKS;
 852                 direct_blk_idx++) {
 853                 blknr = read_allocated_block(g_parent_inode, direct_blk_idx);
 854                 if (blknr == 0)
 855                         break;
 856                 inodeno = unlink_filename(filename, blknr);
 857                 if (inodeno != -1)
 858                         return inodeno;
 859         }
 860
 861         return -1;
 862 }
 863
 864 uint32_t ext4fs_get_new_blk_no(void)
 865 {
 866         short i;
 867         short status;
 868         int remainder;
 869         unsigned int bg_idx;
 870         static int prev_bg_bitmap_index = -1;
 871         unsigned int blk_per_grp = le32_to_cpu(ext4fs_root->sblock.blocks_per_group);
 872         struct ext_filesystem *fs = get_fs();
 873         char *journal_buffer = zalloc(fs->blksz);
 874         char *zero_buffer = zalloc(fs->blksz);
 875         if (!journal_buffer || !zero_buffer)
 876                 goto fail;
 877         struct ext2_block_group *bgd = (struct ext2_block_group *)fs->gdtable;
 878
 879         if (fs->first_pass_bbmap == 0) {
 880                 for (i = 0; i < fs->no_blkgrp; i++) {
 881                         if (le16_to_cpu(bgd[i].free_blocks)) {
 882                                 if (le16_to_cpu(bgd[i].bg_flags) & EXT4_BG_BLOCK_UNINIT) {
 883                                         uint16_t new_flags;
 884                                         put_ext4((uint64_t)le32_to_cpu(bgd[i].block_id) * fs->blksz,
 885                                                  zero_buffer, fs->blksz);
 886                                         new_flags = le16_to_cpu(bgd[i].bg_flags) & ~EXT4_BG_BLOCK_UNINIT;
 887                                         bgd[i].bg_flags = cpu_to_le16(new_flags);
 888                                         memcpy(fs->blk_bmaps[i], zero_buffer,
 889                                                fs->blksz);
 890                                 }
 891                                 fs->curr_blkno =
 892                                     _get_new_blk_no(fs->blk_bmaps[i]);
 893                                 if (fs->curr_blkno == -1)
 894                                         /* if block bitmap is completely fill */
 895                                         continue;
 896                                 fs->curr_blkno = fs->curr_blkno +
 897                                                 (i * fs->blksz * 8);
 898                                 fs->first_pass_bbmap++;
 899                                 ext4fs_bg_free_blocks_dec(&bgd[i]);
 900                                 ext4fs_sb_free_blocks_dec(fs->sb);
 901                                 status = ext4fs_devread(
 902                                                         (lbaint_t)le32_to_cpu(bgd[i].block_id) *
 903                                                         fs->sect_perblk, 0,
 904                                                         fs->blksz,
 905                                                         journal_buffer);
 906                                 if (status == 0)
 907                                         goto fail;
 908                                 if (ext4fs_log_journal(journal_buffer,
 909                                                         le32_to_cpu(bgd[i].block_id)))
 910                                         goto fail;
 911                                 goto success;
 912                         } else {
 913                                 debug("no space left on block group %d\n", i);
 914                         }
 915                 }
 916
 917                 goto fail;
 918         } else {
 919 restart:
 920                 fs->curr_blkno++;
 921                 /* get the blockbitmap index respective to blockno */
 922                 bg_idx = fs->curr_blkno / blk_per_grp;
 923                 if (fs->blksz == 1024) {
 924                         remainder = fs->curr_blkno % blk_per_grp;
 925                         if (!remainder)
 926                                 bg_idx--;
 927                 }
 928
 929                 /*
 930                  * To skip completely filled block group bitmaps
 931                  * Optimize the block allocation
 932                  */
 933                 if (bg_idx >= fs->no_blkgrp)
 934                         goto fail;
 935
 936                 if (bgd[bg_idx].free_blocks == 0) {
 937                         debug("block group %u is full. Skipping\n", bg_idx);
 938                         fs->curr_blkno = fs->curr_blkno + blk_per_grp;
 939                         fs->curr_blkno--;
 940                         goto restart;
 941                 }
 942
 943                 if (le16_to_cpu(bgd[bg_idx].bg_flags) & EXT4_BG_BLOCK_UNINIT) {
 944                         uint16_t new_flags;
 945                         memset(zero_buffer, '\0', fs->blksz);
 946                         put_ext4((uint64_t)le32_to_cpu(bgd[bg_idx].block_id) * fs->blksz,
 947                                  zero_buffer, fs->blksz);
 948                         memcpy(fs->blk_bmaps[bg_idx], zero_buffer, fs->blksz);
 949                         new_flags = le16_to_cpu(bgd[bg_idx].bg_flags) & ~EXT4_BG_BLOCK_UNINIT;
 950                         bgd[bg_idx].bg_flags = cpu_to_le16(new_flags);
 951                 }
 952
 953                 if (ext4fs_set_block_bmap(fs->curr_blkno, fs->blk_bmaps[bg_idx],
 954                                    bg_idx) != 0) {
 955                         debug("going for restart for the block no %ld %u\n",
 956                               fs->curr_blkno, bg_idx);
 957                         goto restart;
 958                 }
 959
 960                 /* journal backup */
 961                 if (prev_bg_bitmap_index != bg_idx) {
 962                         memset(journal_buffer, '\0', fs->blksz);
 963                         status = ext4fs_devread(
 964                                                 (lbaint_t)le32_to_cpu(bgd[bg_idx].block_id)
 965                                                 * fs->sect_perblk,
 966                                                 0, fs->blksz, journal_buffer);
 967                         if (status == 0)
 968                                 goto fail;
 969                         if (ext4fs_log_journal(journal_buffer,
 970                                                 le32_to_cpu(bgd[bg_idx].block_id)))
 971                                 goto fail;
 972
 973                         prev_bg_bitmap_index = bg_idx;
 974                 }
 975                 ext4fs_bg_free_blocks_dec(&bgd[bg_idx]);
 976                 ext4fs_sb_free_blocks_dec(fs->sb);
 977                 goto success;
 978         }
 979 success:
 980         free(journal_buffer);
 981         free(zero_buffer);
 982
 983         return fs->curr_blkno;
 984 fail:
 985         free(journal_buffer);
 986         free(zero_buffer);
 987
 988         return -1;
 989 }
 990
 991 int ext4fs_get_new_inode_no(void)
 992 {
 993         short i;
 994         short status;
 995         unsigned int ibmap_idx;
 996         static int prev_inode_bitmap_index = -1;
 997         unsigned int inodes_per_grp = le32_to_cpu(ext4fs_root->sblock.inodes_per_group);
 998         struct ext_filesystem *fs = get_fs();
 999         char *journal_buffer = zalloc(fs->blksz);
1000         char *zero_buffer = zalloc(fs->blksz);
1001         if (!journal_buffer || !zero_buffer)
1002                 goto fail;
1003         struct ext2_block_group *bgd = (struct ext2_block_group *)fs->gdtable;
1004
1005         if (fs->first_pass_ibmap == 0) {
1006                 for (i = 0; i < fs->no_blkgrp; i++) {
1007                         if (bgd[i].free_inodes) {
1008                                 if (bgd[i].bg_itable_unused !=
1009                                                 bgd[i].free_inodes)
1010                                         bgd[i].bg_itable_unused =
1011                                                 bgd[i].free_inodes;
1012                                 if (le16_to_cpu(bgd[i].bg_flags) & EXT4_BG_INODE_UNINIT) {
1013                                         int new_flags;
1014                                         put_ext4((uint64_t)le32_to_cpu(bgd[i].inode_id) * fs->blksz,
1015                                                  zero_buffer, fs->blksz);
1016                                         new_flags = le16_to_cpu(bgd[i].bg_flags) & ~EXT4_BG_INODE_UNINIT;
1017                                         bgd[i].bg_flags = cpu_to_le16(new_flags);
1018                                         memcpy(fs->inode_bmaps[i],
1019                                                zero_buffer, fs->blksz);
1020                                 }
1021                                 fs->curr_inode_no =
1022                                     _get_new_inode_no(fs->inode_bmaps[i]);
1023                                 if (fs->curr_inode_no == -1)
1024                                         /* if block bitmap is completely fill */
1025                                         continue;
1026                                 fs->curr_inode_no = fs->curr_inode_no +
1027                                                         (i * inodes_per_grp);
1028                                 fs->first_pass_ibmap++;
1029                                 ext4fs_bg_free_inodes_dec(&bgd[i]);
1030                                 ext4fs_bg_itable_unused_dec(&bgd[i]);
1031                                 ext4fs_sb_free_inodes_dec(fs->sb);
1032                                 status = ext4fs_devread(
1033                                                         (lbaint_t)le32_to_cpu(bgd[i].inode_id) *
1034                                                         fs->sect_perblk, 0,
1035                                                         fs->blksz,
1036                                                         journal_buffer);
1037                                 if (status == 0)
1038                                         goto fail;
1039                                 if (ext4fs_log_journal(journal_buffer,
1040                                                         le32_to_cpu(bgd[i].inode_id)))
1041                                         goto fail;
1042                                 goto success;
1043                         } else
1044                                 debug("no inode left on block group %d\n", i);
1045                 }
1046                 goto fail;
1047         } else {
1048 restart:
1049                 fs->curr_inode_no++;
1050                 /* get the blockbitmap index respective to blockno */
1051                 ibmap_idx = fs->curr_inode_no / inodes_per_grp;
1052                 if (le16_to_cpu(bgd[ibmap_idx].bg_flags) & EXT4_BG_INODE_UNINIT) {
1053                         int new_flags;
1054                         memset(zero_buffer, '\0', fs->blksz);
1055                         put_ext4((uint64_t)le32_to_cpu(bgd[ibmap_idx].inode_id) * fs->blksz,
1056                                  zero_buffer, fs->blksz);
1057                         new_flags = le16_to_cpu(bgd[ibmap_idx].bg_flags) & ~EXT4_BG_INODE_UNINIT;
1058                         bgd[ibmap_idx].bg_flags = cpu_to_le16(new_flags);
1059                         memcpy(fs->inode_bmaps[ibmap_idx], zero_buffer,
1060                                 fs->blksz);
1061                 }
1062
1063                 if (ext4fs_set_inode_bmap(fs->curr_inode_no,
1064                                           fs->inode_bmaps[ibmap_idx],
1065                                           ibmap_idx) != 0) {
1066                         debug("going for restart for the block no %d %u\n",
1067                               fs->curr_inode_no, ibmap_idx);
1068                         goto restart;
1069                 }
1070
1071                 /* journal backup */
1072                 if (prev_inode_bitmap_index != ibmap_idx) {
1073                         memset(journal_buffer, '\0', fs->blksz);
1074                         status = ext4fs_devread(
1075                                                 (lbaint_t)le32_to_cpu(bgd[ibmap_idx].inode_id)
1076                                                 * fs->sect_perblk,
1077                                                 0, fs->blksz, journal_buffer);
1078                         if (status == 0)
1079                                 goto fail;
1080                         if (ext4fs_log_journal(journal_buffer,
1081                                                 le32_to_cpu(bgd[ibmap_idx].inode_id)))
1082                                 goto fail;
1083                         prev_inode_bitmap_index = ibmap_idx;
1084                 }
1085                 if (bgd[ibmap_idx].bg_itable_unused !=
1086                                 bgd[ibmap_idx].free_inodes)
1087                         bgd[ibmap_idx].bg_itable_unused =
1088                                         bgd[ibmap_idx].free_inodes;
1089                 ext4fs_bg_free_inodes_dec(&bgd[ibmap_idx]);
1090                 ext4fs_bg_itable_unused_dec(&bgd[ibmap_idx]);
1091                 ext4fs_sb_free_inodes_dec(fs->sb);
1092                 goto success;
1093         }
1094
1095 success:
1096         free(journal_buffer);
1097         free(zero_buffer);
1098
1099         return fs->curr_inode_no;
1100 fail:
1101         free(journal_buffer);
1102         free(zero_buffer);
1103
1104         return -1;
1105
1106 }
1107
1108
1109 static void alloc_single_indirect_block(struct ext2_inode *file_inode,
1110                                         unsigned int *total_remaining_blocks,
1111                                         unsigned int *no_blks_reqd)
1112 {
1113         short i;
1114         short status;
1115         long int actual_block_no;
1116         long int si_blockno;
1117         /* si :single indirect */
1118         __le32 *si_buffer = NULL;
1119         __le32 *si_start_addr = NULL;
1120         struct ext_filesystem *fs = get_fs();
1121
1122         if (*total_remaining_blocks != 0) {
1123                 si_buffer = zalloc(fs->blksz);
1124                 if (!si_buffer) {
1125                         printf("No Memory\n");
1126                         return;
1127                 }
1128                 si_start_addr = si_buffer;
1129                 si_blockno = ext4fs_get_new_blk_no();
1130                 if (si_blockno == -1) {
1131                         printf("no block left to assign\n");
1132                         goto fail;
1133                 }
1134                 (*no_blks_reqd)++;
1135                 debug("SIPB %ld: %u\n", si_blockno, *total_remaining_blocks);
1136
1137                 status = ext4fs_devread((lbaint_t)si_blockno * fs->sect_perblk,
1138                                         0, fs->blksz, (char *)si_buffer);
1139                 memset(si_buffer, '\0', fs->blksz);
1140                 if (status == 0)
1141                         goto fail;
1142
1143                 for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
1144                         actual_block_no = ext4fs_get_new_blk_no();
1145                         if (actual_block_no == -1) {
1146                                 printf("no block left to assign\n");
1147                                 goto fail;
1148                         }
1149                         *si_buffer = cpu_to_le32(actual_block_no);
1150                         debug("SIAB %u: %u\n", *si_buffer,
1151                                 *total_remaining_blocks);
1152
1153                         si_buffer++;
1154                         (*total_remaining_blocks)--;
1155                         if (*total_remaining_blocks == 0)
1156                                 break;
1157                 }
1158
1159                 /* write the block to disk */
1160                 put_ext4(((uint64_t) ((uint64_t)si_blockno * (uint64_t)fs->blksz)),
1161                          si_start_addr, fs->blksz);
1162                 file_inode->b.blocks.indir_block = cpu_to_le32(si_blockno);
1163         }
1164 fail:
1165         free(si_start_addr);
1166 }
1167
1168 static void alloc_double_indirect_block(struct ext2_inode *file_inode,
1169                                         unsigned int *total_remaining_blocks,
1170                                         unsigned int *no_blks_reqd)
1171 {
1172         short i;
1173         short j;
1174         short status;
1175         long int actual_block_no;
1176         /* di:double indirect */
1177         long int di_blockno_parent;
1178         long int di_blockno_child;
1179         __le32 *di_parent_buffer = NULL;
1180         __le32 *di_child_buff = NULL;
1181         __le32 *di_block_start_addr = NULL;
1182         __le32 *di_child_buff_start = NULL;
1183         struct ext_filesystem *fs = get_fs();
1184
1185         if (*total_remaining_blocks != 0) {
1186                 /* double indirect parent block connecting to inode */
1187                 di_blockno_parent = ext4fs_get_new_blk_no();
1188                 if (di_blockno_parent == -1) {
1189                         printf("no block left to assign\n");
1190                         goto fail;
1191                 }
1192                 di_parent_buffer = zalloc(fs->blksz);
1193                 if (!di_parent_buffer)
1194                         goto fail;
1195
1196                 di_block_start_addr = di_parent_buffer;
1197                 (*no_blks_reqd)++;
1198                 debug("DIPB %ld: %u\n", di_blockno_parent,
1199                       *total_remaining_blocks);
1200
1201                 status = ext4fs_devread((lbaint_t)di_blockno_parent *
1202                                         fs->sect_perblk, 0,
1203                                         fs->blksz, (char *)di_parent_buffer);
1204
1205                 if (!status) {
1206                         printf("%s: Device read error!\n", __func__);
1207                         goto fail;
1208                 }
1209                 memset(di_parent_buffer, '\0', fs->blksz);
1210
1211                 /*
1212                  * start:for each double indirect parent
1213                  * block create one more block
1214                  */
1215                 for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
1216                         di_blockno_child = ext4fs_get_new_blk_no();
1217                         if (di_blockno_child == -1) {
1218                                 printf("no block left to assign\n");
1219                                 goto fail;
1220                         }
1221                         di_child_buff = zalloc(fs->blksz);
1222                         if (!di_child_buff)
1223                                 goto fail;
1224
1225                         di_child_buff_start = di_child_buff;
1226                         *di_parent_buffer = cpu_to_le32(di_blockno_child);
1227                         di_parent_buffer++;
1228                         (*no_blks_reqd)++;
1229                         debug("DICB %ld: %u\n", di_blockno_child,
1230                               *total_remaining_blocks);
1231
1232                         status = ext4fs_devread((lbaint_t)di_blockno_child *
1233                                                 fs->sect_perblk, 0,
1234                                                 fs->blksz,
1235                                                 (char *)di_child_buff);
1236
1237                         if (!status) {
1238                                 printf("%s: Device read error!\n", __func__);
1239                                 goto fail;
1240                         }
1241                         memset(di_child_buff, '\0', fs->blksz);
1242                         /* filling of actual datablocks for each child */
1243                         for (j = 0; j < (fs->blksz / sizeof(int)); j++) {
1244                                 actual_block_no = ext4fs_get_new_blk_no();
1245                                 if (actual_block_no == -1) {
1246                                         printf("no block left to assign\n");
1247                                         goto fail;
1248                                 }
1249                                 *di_child_buff = cpu_to_le32(actual_block_no);
1250                                 debug("DIAB %ld: %u\n", actual_block_no,
1251                                       *total_remaining_blocks);
1252
1253                                 di_child_buff++;
1254                                 (*total_remaining_blocks)--;
1255                                 if (*total_remaining_blocks == 0)
1256                                         break;
1257                         }
1258                         /* write the block  table */
1259                         put_ext4(((uint64_t) ((uint64_t)di_blockno_child * (uint64_t)fs->blksz)),
1260                                  di_child_buff_start, fs->blksz);
1261                         free(di_child_buff_start);
1262                         di_child_buff_start = NULL;
1263
1264                         if (*total_remaining_blocks == 0)
1265                                 break;
1266                 }
1267                 put_ext4(((uint64_t) ((uint64_t)di_blockno_parent * (uint64_t)fs->blksz)),
1268                          di_block_start_addr, fs->blksz);
1269                 file_inode->b.blocks.double_indir_block = cpu_to_le32(di_blockno_parent);
1270         }
1271 fail:
1272         free(di_block_start_addr);
1273 }
1274
1275 static void alloc_triple_indirect_block(struct ext2_inode *file_inode,
1276                                         unsigned int *total_remaining_blocks,
1277                                         unsigned int *no_blks_reqd)
1278 {
1279         short i;
1280         short j;
1281         short k;
1282         long int actual_block_no;
1283         /* ti: Triple Indirect */
1284         long int ti_gp_blockno;
1285         long int ti_parent_blockno;
1286         long int ti_child_blockno;
1287         __le32 *ti_gp_buff = NULL;
1288         __le32 *ti_parent_buff = NULL;
1289         __le32 *ti_child_buff = NULL;
1290         __le32 *ti_gp_buff_start_addr = NULL;
1291         __le32 *ti_pbuff_start_addr = NULL;
1292         __le32 *ti_cbuff_start_addr = NULL;
1293         struct ext_filesystem *fs = get_fs();
1294         if (*total_remaining_blocks != 0) {
1295                 /* triple indirect grand parent block connecting to inode */
1296                 ti_gp_blockno = ext4fs_get_new_blk_no();
1297                 if (ti_gp_blockno == -1) {
1298                         printf("no block left to assign\n");
1299                         return;
1300                 }
1301                 ti_gp_buff = zalloc(fs->blksz);
1302                 if (!ti_gp_buff)
1303                         return;
1304
1305                 ti_gp_buff_start_addr = ti_gp_buff;
1306                 (*no_blks_reqd)++;
1307                 debug("TIGPB %ld: %u\n", ti_gp_blockno,
1308                       *total_remaining_blocks);
1309
1310                 /* for each 4 byte grand parent entry create one more block */
1311                 for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
1312                         ti_parent_blockno = ext4fs_get_new_blk_no();
1313                         if (ti_parent_blockno == -1) {
1314                                 printf("no block left to assign\n");
1315                                 goto fail;
1316                         }
1317                         ti_parent_buff = zalloc(fs->blksz);
1318                         if (!ti_parent_buff)
1319                                 goto fail;
1320
1321                         ti_pbuff_start_addr = ti_parent_buff;
1322                         *ti_gp_buff = cpu_to_le32(ti_parent_blockno);
1323                         ti_gp_buff++;
1324                         (*no_blks_reqd)++;
1325                         debug("TIPB %ld: %u\n", ti_parent_blockno,
1326                               *total_remaining_blocks);
1327
1328                         /* for each 4 byte entry parent create one more block */
1329                         for (j = 0; j < (fs->blksz / sizeof(int)); j++) {
1330                                 ti_child_blockno = ext4fs_get_new_blk_no();
1331                                 if (ti_child_blockno == -1) {
1332                                         printf("no block left assign\n");
1333                                         goto fail1;
1334                                 }
1335                                 ti_child_buff = zalloc(fs->blksz);
1336                                 if (!ti_child_buff)
1337                                         goto fail1;
1338
1339                                 ti_cbuff_start_addr = ti_child_buff;
1340                                 *ti_parent_buff = cpu_to_le32(ti_child_blockno);
1341                                 ti_parent_buff++;
1342                                 (*no_blks_reqd)++;
1343                                 debug("TICB %ld: %u\n", ti_parent_blockno,
1344                                       *total_remaining_blocks);
1345
1346                                 /* fill actual datablocks for each child */
1347                                 for (k = 0; k < (fs->blksz / sizeof(int));
1348                                         k++) {
1349                                         actual_block_no =
1350                                             ext4fs_get_new_blk_no();
1351                                         if (actual_block_no == -1) {
1352                                                 printf("no block left\n");
1353                                                 free(ti_cbuff_start_addr);
1354                                                 goto fail1;
1355                                         }
1356                                         *ti_child_buff = cpu_to_le32(actual_block_no);
1357                                         debug("TIAB %ld: %u\n", actual_block_no,
1358                                               *total_remaining_blocks);
1359
1360                                         ti_child_buff++;
1361                                         (*total_remaining_blocks)--;
1362                                         if (*total_remaining_blocks == 0)
1363                                                 break;
1364                                 }
1365                                 /* write the child block */
1366                                 put_ext4(((uint64_t) ((uint64_t)ti_child_blockno *
1367                                                       (uint64_t)fs->blksz)),
1368                                          ti_cbuff_start_addr, fs->blksz);
1369                                 free(ti_cbuff_start_addr);
1370
1371                                 if (*total_remaining_blocks == 0)
1372                                         break;
1373                         }
1374                         /* write the parent block */
1375                         put_ext4(((uint64_t) ((uint64_t)ti_parent_blockno * (uint64_t)fs->blksz)),
1376                                  ti_pbuff_start_addr, fs->blksz);
1377                         free(ti_pbuff_start_addr);
1378
1379                         if (*total_remaining_blocks == 0)
1380                                 break;
1381                 }
1382                 /* write the grand parent block */
1383                 put_ext4(((uint64_t) ((uint64_t)ti_gp_blockno * (uint64_t)fs->blksz)),
1384                          ti_gp_buff_start_addr, fs->blksz);
1385                 file_inode->b.blocks.triple_indir_block = cpu_to_le32(ti_gp_blockno);
1386                 free(ti_gp_buff_start_addr);
1387                 return;
1388         }
1389 fail1:
1390         free(ti_pbuff_start_addr);
1391 fail:
1392         free(ti_gp_buff_start_addr);
1393 }
1394
1395 void ext4fs_allocate_blocks(struct ext2_inode *file_inode,
1396                                 unsigned int total_remaining_blocks,
1397                                 unsigned int *total_no_of_block)
1398 {
1399         short i;
1400         long int direct_blockno;
1401         unsigned int no_blks_reqd = 0;
1402
1403         /* allocation of direct blocks */
1404         for (i = 0; total_remaining_blocks && i < INDIRECT_BLOCKS; i++) {
1405                 direct_blockno = ext4fs_get_new_blk_no();
1406                 if (direct_blockno == -1) {
1407                         printf("no block left to assign\n");
1408                         return;
1409                 }
1410                 file_inode->b.blocks.dir_blocks[i] = cpu_to_le32(direct_blockno);
1411                 debug("DB %ld: %u\n", direct_blockno, total_remaining_blocks);
1412
1413                 total_remaining_blocks--;
1414         }
1415
1416         alloc_single_indirect_block(file_inode, &total_remaining_blocks,
1417                                     &no_blks_reqd);
1418         alloc_double_indirect_block(file_inode, &total_remaining_blocks,
1419                                     &no_blks_reqd);
1420         alloc_triple_indirect_block(file_inode, &total_remaining_blocks,
1421                                     &no_blks_reqd);
1422         *total_no_of_block += no_blks_reqd;
1423 }
1424
1425 #endif
1426
1427 static struct ext4_extent_header *ext4fs_get_extent_block
1428         (struct ext2_data *data, char *buf,
1429                 struct ext4_extent_header *ext_block,
1430                 uint32_t fileblock, int log2_blksz)
1431 {
1432         struct ext4_extent_idx *index;
1433         unsigned long long block;
1434         int blksz = EXT2_BLOCK_SIZE(data);
1435         int i;
1436
1437         while (1) {
1438                 index = (struct ext4_extent_idx *)(ext_block + 1);
1439
1440                 if (le16_to_cpu(ext_block->eh_magic) != EXT4_EXT_MAGIC)
1441                         return NULL;
1442
1443                 if (ext_block->eh_depth == 0)
1444                         return ext_block;
1445                 i = -1;
1446                 do {
1447                         i++;
1448                         if (i >= le16_to_cpu(ext_block->eh_entries))
1449                                 break;
1450                 } while (fileblock >= le32_to_cpu(index[i].ei_block));
1451
1452                 if (--i < 0)
1453                         return NULL;
1454
1455                 block = le16_to_cpu(index[i].ei_leaf_hi);
1456                 block = (block << 32) + le32_to_cpu(index[i].ei_leaf_lo);
1457
1458                 if (ext4fs_devread((lbaint_t)block << log2_blksz, 0, blksz,
1459                                    buf))
1460                         ext_block = (struct ext4_extent_header *)buf;
1461                 else
1462                         return NULL;
1463         }
1464 }
1465
1466 static int ext4fs_blockgroup
1467         (struct ext2_data *data, int group, struct ext2_block_group *blkgrp)
1468 {
1469         long int blkno;
1470         unsigned int blkoff, desc_per_blk;
1471         int log2blksz = get_fs()->dev_desc->log2blksz;
1472
1473         desc_per_blk = EXT2_BLOCK_SIZE(data) / sizeof(struct ext2_block_group);
1474
1475         blkno = le32_to_cpu(data->sblock.first_data_block) + 1 +
1476                         group / desc_per_blk;
1477         blkoff = (group % desc_per_blk) * sizeof(struct ext2_block_group);
1478
1479         debug("ext4fs read %d group descriptor (blkno %ld blkoff %u)\n",
1480               group, blkno, blkoff);
1481
1482         return ext4fs_devread((lbaint_t)blkno <<
1483                               (LOG2_BLOCK_SIZE(data) - log2blksz),
1484                               blkoff, sizeof(struct ext2_block_group),
1485                               (char *)blkgrp);
1486 }
1487
1488 int ext4fs_read_inode(struct ext2_data *data, int ino, struct ext2_inode *inode)
1489 {
1490         struct ext2_block_group blkgrp;
1491         struct ext2_sblock *sblock = &data->sblock;
1492         struct ext_filesystem *fs = get_fs();
1493         int log2blksz = get_fs()->dev_desc->log2blksz;
1494         int inodes_per_block, status;
1495         long int blkno;
1496         unsigned int blkoff;
1497
1498         /* It is easier to calculate if the first inode is 0. */
1499         ino--;
1500         status = ext4fs_blockgroup(data, ino / le32_to_cpu
1501                                    (sblock->inodes_per_group), &blkgrp);
1502         if (status == 0)
1503                 return 0;
1504
1505         inodes_per_block = EXT2_BLOCK_SIZE(data) / fs->inodesz;
1506         blkno = le32_to_cpu(blkgrp.inode_table_id) +
1507             (ino % le32_to_cpu(sblock->inodes_per_group)) / inodes_per_block;
1508         blkoff = (ino % inodes_per_block) * fs->inodesz;
1509         /* Read the inode. */
1510         status = ext4fs_devread((lbaint_t)blkno << (LOG2_BLOCK_SIZE(data) -
1511                                 log2blksz), blkoff,
1512                                 sizeof(struct ext2_inode), (char *)inode);
1513         if (status == 0)
1514                 return 0;
1515
1516         return 1;
1517 }
1518
1519 long int read_allocated_block(struct ext2_inode *inode, int fileblock)
1520 {
1521         long int blknr;
1522         int blksz;
1523         int log2_blksz;
1524         int status;
1525         long int rblock;
1526         long int perblock_parent;
1527         long int perblock_child;
1528         unsigned long long start;
1529         /* get the blocksize of the filesystem */
1530         blksz = EXT2_BLOCK_SIZE(ext4fs_root);
1531         log2_blksz = LOG2_BLOCK_SIZE(ext4fs_root)
1532                 - get_fs()->dev_desc->log2blksz;
1533
1534         if (le32_to_cpu(inode->flags) & EXT4_EXTENTS_FL) {
1535                 char *buf = zalloc(blksz);
1536                 if (!buf)
1537                         return -ENOMEM;
1538                 struct ext4_extent_header *ext_block;
1539                 struct ext4_extent *extent;
1540                 int i = -1;
1541                 ext_block =
1542                         ext4fs_get_extent_block(ext4fs_root, buf,
1543                                                 (struct ext4_extent_header *)
1544                                                 inode->b.blocks.dir_blocks,
1545                                                 fileblock, log2_blksz);
1546                 if (!ext_block) {
1547                         printf("invalid extent block\n");
1548                         free(buf);
1549                         return -EINVAL;
1550                 }
1551
1552                 extent = (struct ext4_extent *)(ext_block + 1);
1553
1554                 do {
1555                         i++;
1556                         if (i >= le16_to_cpu(ext_block->eh_entries))
1557                                 break;
1558                 } while (fileblock >= le32_to_cpu(extent[i].ee_block));
1559                 if (--i >= 0) {
1560                         fileblock -= le32_to_cpu(extent[i].ee_block);
1561                         if (fileblock >= le16_to_cpu(extent[i].ee_len)) {
1562                                 free(buf);
1563                                 return 0;
1564                         }
1565
1566                         start = le16_to_cpu(extent[i].ee_start_hi);
1567                         start = (start << 32) +
1568                                         le32_to_cpu(extent[i].ee_start_lo);
1569                         free(buf);
1570                         return fileblock + start;
1571                 }
1572
1573                 printf("Extent Error\n");
1574                 free(buf);
1575                 return -1;
1576         }
1577
1578         /* Direct blocks. */
1579         if (fileblock < INDIRECT_BLOCKS)
1580                 blknr = le32_to_cpu(inode->b.blocks.dir_blocks[fileblock]);
1581
1582         /* Indirect. */
1583         else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4))) {
1584                 if (ext4fs_indir1_block == NULL) {
1585                         ext4fs_indir1_block = zalloc(blksz);
1586                         if (ext4fs_indir1_block == NULL) {
1587                                 printf("** SI ext2fs read block (indir 1)"
1588                                         "malloc failed. **\n");
1589                                 return -1;
1590                         }
1591                         ext4fs_indir1_size = blksz;
1592                         ext4fs_indir1_blkno = -1;
1593                 }
1594                 if (blksz != ext4fs_indir1_size) {
1595                         free(ext4fs_indir1_block);
1596                         ext4fs_indir1_block = NULL;
1597                         ext4fs_indir1_size = 0;
1598                         ext4fs_indir1_blkno = -1;
1599                         ext4fs_indir1_block = zalloc(blksz);
1600                         if (ext4fs_indir1_block == NULL) {
1601                                 printf("** SI ext2fs read block (indir 1):"
1602                                         "malloc failed. **\n");
1603                                 return -1;
1604                         }
1605                         ext4fs_indir1_size = blksz;
1606                 }
1607                 if ((le32_to_cpu(inode->b.blocks.indir_block) <<
1608                      log2_blksz) != ext4fs_indir1_blkno) {
1609                         status =
1610                             ext4fs_devread((lbaint_t)le32_to_cpu
1611                                            (inode->b.blocks.
1612                                             indir_block) << log2_blksz, 0,
1613                                            blksz, (char *)ext4fs_indir1_block);
1614                         if (status == 0) {
1615                                 printf("** SI ext2fs read block (indir 1)"
1616                                         "failed. **\n");
1617                                 return 0;
1618                         }
1619                         ext4fs_indir1_blkno =
1620                                 le32_to_cpu(inode->b.blocks.
1621                                                indir_block) << log2_blksz;
1622                 }
1623                 blknr = le32_to_cpu(ext4fs_indir1_block
1624                                       [fileblock - INDIRECT_BLOCKS]);
1625         }
1626         /* Double indirect. */
1627         else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4 *
1628                                         (blksz / 4 + 1)))) {
1629
1630                 long int perblock = blksz / 4;
1631                 long int rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4);
1632
1633                 if (ext4fs_indir1_block == NULL) {
1634                         ext4fs_indir1_block = zalloc(blksz);
1635                         if (ext4fs_indir1_block == NULL) {
1636                                 printf("** DI ext2fs read block (indir 2 1)"
1637                                         "malloc failed. **\n");
1638                                 return -1;
1639                         }
1640                         ext4fs_indir1_size = blksz;
1641                         ext4fs_indir1_blkno = -1;
1642                 }
1643                 if (blksz != ext4fs_indir1_size) {
1644                         free(ext4fs_indir1_block);
1645                         ext4fs_indir1_block = NULL;
1646                         ext4fs_indir1_size = 0;
1647                         ext4fs_indir1_blkno = -1;
1648                         ext4fs_indir1_block = zalloc(blksz);
1649                         if (ext4fs_indir1_block == NULL) {
1650                                 printf("** DI ext2fs read block (indir 2 1)"
1651                                         "malloc failed. **\n");
1652                                 return -1;
1653                         }
1654                         ext4fs_indir1_size = blksz;
1655                 }
1656                 if ((le32_to_cpu(inode->b.blocks.double_indir_block) <<
1657                      log2_blksz) != ext4fs_indir1_blkno) {
1658                         status =
1659                             ext4fs_devread((lbaint_t)le32_to_cpu
1660                                            (inode->b.blocks.
1661                                             double_indir_block) << log2_blksz,
1662                                            0, blksz,
1663                                            (char *)ext4fs_indir1_block);
1664                         if (status == 0) {
1665                                 printf("** DI ext2fs read block (indir 2 1)"
1666                                         "failed. **\n");
1667                                 return -1;
1668                         }
1669                         ext4fs_indir1_blkno =
1670                             le32_to_cpu(inode->b.blocks.double_indir_block) <<
1671                             log2_blksz;
1672                 }
1673
1674                 if (ext4fs_indir2_block == NULL) {
1675                         ext4fs_indir2_block = zalloc(blksz);
1676                         if (ext4fs_indir2_block == NULL) {
1677                                 printf("** DI ext2fs read block (indir 2 2)"
1678                                         "malloc failed. **\n");
1679                                 return -1;
1680                         }
1681                         ext4fs_indir2_size = blksz;
1682                         ext4fs_indir2_blkno = -1;
1683                 }
1684                 if (blksz != ext4fs_indir2_size) {
1685                         free(ext4fs_indir2_block);
1686                         ext4fs_indir2_block = NULL;
1687                         ext4fs_indir2_size = 0;
1688                         ext4fs_indir2_blkno = -1;
1689                         ext4fs_indir2_block = zalloc(blksz);
1690                         if (ext4fs_indir2_block == NULL) {
1691                                 printf("** DI ext2fs read block (indir 2 2)"
1692                                         "malloc failed. **\n");
1693                                 return -1;
1694                         }
1695                         ext4fs_indir2_size = blksz;
1696                 }
1697                 if ((le32_to_cpu(ext4fs_indir1_block[rblock / perblock]) <<
1698                      log2_blksz) != ext4fs_indir2_blkno) {
1699                         status = ext4fs_devread((lbaint_t)le32_to_cpu
1700                                                 (ext4fs_indir1_block
1701                                                  [rblock /
1702                                                   perblock]) << log2_blksz, 0,
1703                                                 blksz,
1704                                                 (char *)ext4fs_indir2_block);
1705                         if (status == 0) {
1706                                 printf("** DI ext2fs read block (indir 2 2)"
1707                                         "failed. **\n");
1708                                 return -1;
1709                         }
1710                         ext4fs_indir2_blkno =
1711                             le32_to_cpu(ext4fs_indir1_block[rblock
1712                                                               /
1713                                                               perblock]) <<
1714                             log2_blksz;
1715                 }
1716                 blknr = le32_to_cpu(ext4fs_indir2_block[rblock % perblock]);
1717         }
1718         /* Tripple indirect. */
1719         else {
1720                 rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4 +
1721                                       (blksz / 4 * blksz / 4));
1722                 perblock_child = blksz / 4;
1723                 perblock_parent = ((blksz / 4) * (blksz / 4));
1724
1725                 if (ext4fs_indir1_block == NULL) {
1726                         ext4fs_indir1_block = zalloc(blksz);
1727                         if (ext4fs_indir1_block == NULL) {
1728                                 printf("** TI ext2fs read block (indir 2 1)"
1729                                         "malloc failed. **\n");
1730                                 return -1;
1731                         }
1732                         ext4fs_indir1_size = blksz;
1733                         ext4fs_indir1_blkno = -1;
1734                 }
1735                 if (blksz != ext4fs_indir1_size) {
1736                         free(ext4fs_indir1_block);
1737                         ext4fs_indir1_block = NULL;
1738                         ext4fs_indir1_size = 0;
1739                         ext4fs_indir1_blkno = -1;
1740                         ext4fs_indir1_block = zalloc(blksz);
1741                         if (ext4fs_indir1_block == NULL) {
1742                                 printf("** TI ext2fs read block (indir 2 1)"
1743                                         "malloc failed. **\n");
1744                                 return -1;
1745                         }
1746                         ext4fs_indir1_size = blksz;
1747                 }
1748                 if ((le32_to_cpu(inode->b.blocks.triple_indir_block) <<
1749                      log2_blksz) != ext4fs_indir1_blkno) {
1750                         status = ext4fs_devread
1751                             ((lbaint_t)
1752                              le32_to_cpu(inode->b.blocks.triple_indir_block)
1753                              << log2_blksz, 0, blksz,
1754                              (char *)ext4fs_indir1_block);
1755                         if (status == 0) {
1756                                 printf("** TI ext2fs read block (indir 2 1)"
1757                                         "failed. **\n");
1758                                 return -1;
1759                         }
1760                         ext4fs_indir1_blkno =
1761                             le32_to_cpu(inode->b.blocks.triple_indir_block) <<
1762                             log2_blksz;
1763                 }
1764
1765                 if (ext4fs_indir2_block == NULL) {
1766                         ext4fs_indir2_block = zalloc(blksz);
1767                         if (ext4fs_indir2_block == NULL) {
1768                                 printf("** TI ext2fs read block (indir 2 2)"
1769                                         "malloc failed. **\n");
1770                                 return -1;
1771                         }
1772                         ext4fs_indir2_size = blksz;
1773                         ext4fs_indir2_blkno = -1;
1774                 }
1775                 if (blksz != ext4fs_indir2_size) {
1776                         free(ext4fs_indir2_block);
1777                         ext4fs_indir2_block = NULL;
1778                         ext4fs_indir2_size = 0;
1779                         ext4fs_indir2_blkno = -1;
1780                         ext4fs_indir2_block = zalloc(blksz);
1781                         if (ext4fs_indir2_block == NULL) {
1782                                 printf("** TI ext2fs read block (indir 2 2)"
1783                                         "malloc failed. **\n");
1784                                 return -1;
1785                         }
1786                         ext4fs_indir2_size = blksz;
1787                 }
1788                 if ((le32_to_cpu(ext4fs_indir1_block[rblock /
1789                                                        perblock_parent]) <<
1790                      log2_blksz)
1791                     != ext4fs_indir2_blkno) {
1792                         status = ext4fs_devread((lbaint_t)le32_to_cpu
1793                                                 (ext4fs_indir1_block
1794                                                  [rblock /
1795                                                   perblock_parent]) <<
1796                                                 log2_blksz, 0, blksz,
1797                                                 (char *)ext4fs_indir2_block);
1798                         if (status == 0) {
1799                                 printf("** TI ext2fs read block (indir 2 2)"
1800                                         "failed. **\n");
1801                                 return -1;
1802                         }
1803                         ext4fs_indir2_blkno =
1804                             le32_to_cpu(ext4fs_indir1_block[rblock /
1805                                                               perblock_parent])
1806                             << log2_blksz;
1807                 }
1808
1809                 if (ext4fs_indir3_block == NULL) {
1810                         ext4fs_indir3_block = zalloc(blksz);
1811                         if (ext4fs_indir3_block == NULL) {
1812                                 printf("** TI ext2fs read block (indir 2 2)"
1813                                         "malloc failed. **\n");
1814                                 return -1;
1815                         }
1816                         ext4fs_indir3_size = blksz;
1817                         ext4fs_indir3_blkno = -1;
1818                 }
1819                 if (blksz != ext4fs_indir3_size) {
1820                         free(ext4fs_indir3_block);
1821                         ext4fs_indir3_block = NULL;
1822                         ext4fs_indir3_size = 0;
1823                         ext4fs_indir3_blkno = -1;
1824                         ext4fs_indir3_block = zalloc(blksz);
1825                         if (ext4fs_indir3_block == NULL) {
1826                                 printf("** TI ext2fs read block (indir 2 2)"
1827                                         "malloc failed. **\n");
1828                                 return -1;
1829                         }
1830                         ext4fs_indir3_size = blksz;
1831                 }
1832                 if ((le32_to_cpu(ext4fs_indir2_block[rblock
1833                                                        /
1834                                                        perblock_child]) <<
1835                      log2_blksz) != ext4fs_indir3_blkno) {
1836                         status =
1837                             ext4fs_devread((lbaint_t)le32_to_cpu
1838                                            (ext4fs_indir2_block
1839                                             [(rblock / perblock_child)
1840                                              % (blksz / 4)]) << log2_blksz, 0,
1841                                            blksz, (char *)ext4fs_indir3_block);
1842                         if (status == 0) {
1843                                 printf("** TI ext2fs read block (indir 2 2)"
1844                                        "failed. **\n");
1845                                 return -1;
1846                         }
1847                         ext4fs_indir3_blkno =
1848                             le32_to_cpu(ext4fs_indir2_block[(rblock /
1849                                                                perblock_child) %
1850                                                               (blksz /
1851                                                                4)]) <<
1852                             log2_blksz;
1853                 }
1854
1855                 blknr = le32_to_cpu(ext4fs_indir3_block
1856                                       [rblock % perblock_child]);
1857         }
1858         debug("read_allocated_block %ld\n", blknr);
1859
1860         return blknr;
1861 }
1862
1863 /**
1864  * ext4fs_reinit_global() - Reinitialize values of ext4 write implementation's
1865  *                          global pointers
1866  *
1867  * This function assures that for a file with the same name but different size
1868  * the sequential store on the ext4 filesystem will be correct.
1869  *
1870  * In this function the global data, responsible for internal representation
1871  * of the ext4 data are initialized to the reset state. Without this, during
1872  * replacement of the smaller file with the bigger truncation of new file was
1873  * performed.
1874  */
1875 void ext4fs_reinit_global(void)
1876 {
1877         if (ext4fs_indir1_block != NULL) {
1878                 free(ext4fs_indir1_block);
1879                 ext4fs_indir1_block = NULL;
1880                 ext4fs_indir1_size = 0;
1881                 ext4fs_indir1_blkno = -1;
1882         }
1883         if (ext4fs_indir2_block != NULL) {
1884                 free(ext4fs_indir2_block);
1885                 ext4fs_indir2_block = NULL;
1886                 ext4fs_indir2_size = 0;
1887                 ext4fs_indir2_blkno = -1;
1888         }
1889         if (ext4fs_indir3_block != NULL) {
1890                 free(ext4fs_indir3_block);
1891                 ext4fs_indir3_block = NULL;
1892                 ext4fs_indir3_size = 0;
1893                 ext4fs_indir3_blkno = -1;
1894         }
1895 }
1896 void ext4fs_close(void)
1897 {
1898         if ((ext4fs_file != NULL) && (ext4fs_root != NULL)) {
1899                 ext4fs_free_node(ext4fs_file, &ext4fs_root->diropen);
1900                 ext4fs_file = NULL;
1901         }
1902         if (ext4fs_root != NULL) {
1903                 free(ext4fs_root);
1904                 ext4fs_root = NULL;
1905         }
1906
1907         ext4fs_reinit_global();
1908 }
1909
1910 int ext4fs_iterate_dir(struct ext2fs_node *dir, char *name,
1911                                 struct ext2fs_node **fnode, int *ftype)
1912 {
1913         unsigned int fpos = 0;
1914         int status;
1915         loff_t actread;
1916         struct ext2fs_node *diro = (struct ext2fs_node *) dir;
1917
1918 #ifdef DEBUG
1919         if (name != NULL)
1920                 printf("Iterate dir %s\n", name);
1921 #endif /* of DEBUG */
1922         if (!diro->inode_read) {
1923                 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode);
1924                 if (status == 0)
1925                         return 0;
1926         }
1927         /* Search the file.  */
1928         while (fpos < le32_to_cpu(diro->inode.size)) {
1929                 struct ext2_dirent dirent;
1930
1931                 status = ext4fs_read_file(diro, fpos,
1932                                            sizeof(struct ext2_dirent),
1933                                            (char *)&dirent, &actread);
1934                 if (status < 0)
1935                         return 0;
1936
1937                 if (dirent.direntlen == 0) {
1938                         printf("Failed to iterate over directory %s\n", name);
1939                         return 0;
1940                 }
1941
1942                 if (dirent.namelen != 0) {
1943                         char filename[dirent.namelen + 1];
1944                         struct ext2fs_node *fdiro;
1945                         int type = FILETYPE_UNKNOWN;
1946
1947                         status = ext4fs_read_file(diro,
1948                                                   fpos +
1949                                                   sizeof(struct ext2_dirent),
1950                                                   dirent.namelen, filename,
1951                                                   &actread);
1952                         if (status < 0)
1953                                 return 0;
1954
1955                         fdiro = zalloc(sizeof(struct ext2fs_node));
1956                         if (!fdiro)
1957                                 return 0;
1958
1959                         fdiro->data = diro->data;
1960                         fdiro->ino = le32_to_cpu(dirent.inode);
1961
1962                         filename[dirent.namelen] = '\0';
1963
1964                         if (dirent.filetype != FILETYPE_UNKNOWN) {
1965                                 fdiro->inode_read = 0;
1966
1967                                 if (dirent.filetype == FILETYPE_DIRECTORY)
1968                                         type = FILETYPE_DIRECTORY;
1969                                 else if (dirent.filetype == FILETYPE_SYMLINK)
1970                                         type = FILETYPE_SYMLINK;
1971                                 else if (dirent.filetype == FILETYPE_REG)
1972                                         type = FILETYPE_REG;
1973                         } else {
1974                                 status = ext4fs_read_inode(diro->data,
1975                                                            le32_to_cpu
1976                                                            (dirent.inode),
1977                                                            &fdiro->inode);
1978                                 if (status == 0) {
1979                                         free(fdiro);
1980                                         return 0;
1981                                 }
1982                                 fdiro->inode_read = 1;
1983
1984                                 if ((le16_to_cpu(fdiro->inode.mode) &
1985                                      FILETYPE_INO_MASK) ==
1986                                     FILETYPE_INO_DIRECTORY) {
1987                                         type = FILETYPE_DIRECTORY;
1988                                 } else if ((le16_to_cpu(fdiro->inode.mode)
1989                                             & FILETYPE_INO_MASK) ==
1990                                            FILETYPE_INO_SYMLINK) {
1991                                         type = FILETYPE_SYMLINK;
1992                                 } else if ((le16_to_cpu(fdiro->inode.mode)
1993                                             & FILETYPE_INO_MASK) ==
1994                                            FILETYPE_INO_REG) {
1995                                         type = FILETYPE_REG;
1996                                 }
1997                         }
1998 #ifdef DEBUG
1999                         printf("iterate >%s<\n", filename);
2000 #endif /* of DEBUG */
2001                         if ((name != NULL) && (fnode != NULL)
2002                             && (ftype != NULL)) {
2003                                 if (strcmp(filename, name) == 0) {
2004                                         *ftype = type;
2005                                         *fnode = fdiro;
2006                                         return 1;
2007                                 }
2008                         } else {
2009                                 if (fdiro->inode_read == 0) {
2010                                         status = ext4fs_read_inode(diro->data,
2011                                                                  le32_to_cpu(
2012                                                                  dirent.inode),
2013                                                                  &fdiro->inode);
2014                                         if (status == 0) {
2015                                                 free(fdiro);
2016                                                 return 0;
2017                                         }
2018                                         fdiro->inode_read = 1;
2019                                 }
2020                                 switch (type) {
2021                                 case FILETYPE_DIRECTORY:
2022                                         printf("<DIR> ");
2023                                         break;
2024                                 case FILETYPE_SYMLINK:
2025                                         printf("<SYM> ");
2026                                         break;
2027                                 case FILETYPE_REG:
2028                                         printf("      ");
2029                                         break;
2030                                 default:
2031                                         printf("< ? > ");
2032                                         break;
2033                                 }
2034                                 printf("%10u %s\n",
2035                                        le32_to_cpu(fdiro->inode.size),
2036                                         filename);
2037                         }
2038                         free(fdiro);
2039                 }
2040                 fpos += le16_to_cpu(dirent.direntlen);
2041         }
2042         return 0;
2043 }
2044
2045 static char *ext4fs_read_symlink(struct ext2fs_node *node)
2046 {
2047         char *symlink;
2048         struct ext2fs_node *diro = node;
2049         int status;
2050         loff_t actread;
2051
2052         if (!diro->inode_read) {
2053                 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode);
2054                 if (status == 0)
2055                         return NULL;
2056         }
2057         symlink = zalloc(le32_to_cpu(diro->inode.size) + 1);
2058         if (!symlink)
2059                 return NULL;
2060
2061         if (le32_to_cpu(diro->inode.size) < sizeof(diro->inode.b.symlink)) {
2062                 strncpy(symlink, diro->inode.b.symlink,
2063                          le32_to_cpu(diro->inode.size));
2064         } else {
2065                 status = ext4fs_read_file(diro, 0,
2066                                            le32_to_cpu(diro->inode.size),
2067                                            symlink, &actread);
2068                 if ((status < 0) || (actread == 0)) {
2069                         free(symlink);
2070                         return NULL;
2071                 }
2072         }
2073         symlink[le32_to_cpu(diro->inode.size)] = '\0';
2074         return symlink;
2075 }
2076
2077 static int ext4fs_find_file1(const char *currpath,
2078                              struct ext2fs_node *currroot,
2079                              struct ext2fs_node **currfound, int *foundtype)
2080 {
2081         char fpath[strlen(currpath) + 1];
2082         char *name = fpath;
2083         char *next;
2084         int status;
2085         int type = FILETYPE_DIRECTORY;
2086         struct ext2fs_node *currnode = currroot;
2087         struct ext2fs_node *oldnode = currroot;
2088
2089         strncpy(fpath, currpath, strlen(currpath) + 1);
2090
2091         /* Remove all leading slashes. */
2092         while (*name == '/')
2093                 name++;
2094
2095         if (!*name) {
2096                 *currfound = currnode;
2097                 return 1;
2098         }
2099
2100         for (;;) {
2101                 int found;
2102
2103                 /* Extract the actual part from the pathname. */
2104                 next = strchr(name, '/');
2105                 if (next) {
2106                         /* Remove all leading slashes. */
2107                         while (*next == '/')
2108                                 *(next++) = '\0';
2109                 }
2110
2111                 if (type != FILETYPE_DIRECTORY) {
2112                         ext4fs_free_node(currnode, currroot);
2113                         return 0;
2114                 }
2115
2116                 oldnode = currnode;
2117
2118                 /* Iterate over the directory. */
2119                 found = ext4fs_iterate_dir(currnode, name, &currnode, &type);
2120                 if (found == 0)
2121                         return 0;
2122
2123                 if (found == -1)
2124                         break;
2125
2126                 /* Read in the symlink and follow it. */
2127                 if (type == FILETYPE_SYMLINK) {
2128                         char *symlink;
2129
2130                         /* Test if the symlink does not loop. */
2131                         if (++symlinknest == 8) {
2132                                 ext4fs_free_node(currnode, currroot);
2133                                 ext4fs_free_node(oldnode, currroot);
2134                                 return 0;
2135                         }
2136
2137                         symlink = ext4fs_read_symlink(currnode);
2138                         ext4fs_free_node(currnode, currroot);
2139
2140                         if (!symlink) {
2141                                 ext4fs_free_node(oldnode, currroot);
2142                                 return 0;
2143                         }
2144
2145                         debug("Got symlink >%s<\n", symlink);
2146
2147                         if (symlink[0] == '/') {
2148                                 ext4fs_free_node(oldnode, currroot);
2149                                 oldnode = &ext4fs_root->diropen;
2150                         }
2151
2152                         /* Lookup the node the symlink points to. */
2153                         status = ext4fs_find_file1(symlink, oldnode,
2154                                                     &currnode, &type);
2155
2156                         free(symlink);
2157
2158                         if (status == 0) {
2159                                 ext4fs_free_node(oldnode, currroot);
2160                                 return 0;
2161                         }
2162                 }
2163
2164                 ext4fs_free_node(oldnode, currroot);
2165
2166                 /* Found the node! */
2167                 if (!next || *next == '\0') {
2168                         *currfound = currnode;
2169                         *foundtype = type;
2170                         return 1;
2171                 }
2172                 name = next;
2173         }
2174         return -1;
2175 }
2176
2177 int ext4fs_find_file(const char *path, struct ext2fs_node *rootnode,
2178         struct ext2fs_node **foundnode, int expecttype)
2179 {
2180         int status;
2181         int foundtype = FILETYPE_DIRECTORY;
2182
2183         symlinknest = 0;
2184         if (!path)
2185                 return 0;
2186
2187         status = ext4fs_find_file1(path, rootnode, foundnode, &foundtype);
2188         if (status == 0)
2189                 return 0;
2190
2191         /* Check if the node that was found was of the expected type. */
2192         if ((expecttype == FILETYPE_REG) && (foundtype != expecttype))
2193                 return 0;
2194         else if ((expecttype == FILETYPE_DIRECTORY)
2195                    && (foundtype != expecttype))
2196                 return 0;
2197
2198         return 1;
2199 }
2200
2201 int ext4fs_open(const char *filename, loff_t *len)
2202 {
2203         struct ext2fs_node *fdiro = NULL;
2204         int status;
2205
2206         if (ext4fs_root == NULL)
2207                 return -1;
2208
2209         ext4fs_file = NULL;
2210         status = ext4fs_find_file(filename, &ext4fs_root->diropen, &fdiro,
2211                                   FILETYPE_REG);
2212         if (status == 0)
2213                 goto fail;
2214
2215         if (!fdiro->inode_read) {
2216                 status = ext4fs_read_inode(fdiro->data, fdiro->ino,
2217                                 &fdiro->inode);
2218                 if (status == 0)
2219                         goto fail;
2220         }
2221         *len = le32_to_cpu(fdiro->inode.size);
2222         ext4fs_file = fdiro;
2223
2224         return 0;
2225 fail:
2226         ext4fs_free_node(fdiro, &ext4fs_root->diropen);
2227
2228         return -1;
2229 }
2230
2231 int ext4fs_mount(unsigned part_length)
2232 {
2233         struct ext2_data *data;
2234         int status;
2235         struct ext_filesystem *fs = get_fs();
2236         data = zalloc(SUPERBLOCK_SIZE);
2237         if (!data)
2238                 return 0;
2239
2240         /* Read the superblock. */
2241         status = ext4_read_superblock((char *)&data->sblock);
2242
2243         if (status == 0)
2244                 goto fail;
2245
2246         /* Make sure this is an ext2 filesystem. */
2247         if (le16_to_cpu(data->sblock.magic) != EXT2_MAGIC)
2248                 goto fail;
2249
2250         /*
2251          * The 64bit feature was enabled when metadata_csum was enabled
2252          * and we do not support metadata_csum (and cannot reliably find
2253          * files when it is set.  Refuse to mount.
2254          */
2255         if (le32_to_cpu(data->sblock.feature_incompat) & EXT4_FEATURE_INCOMPAT_64BIT) {
2256                 printf("Unsupported feature found (64bit, possibly metadata_csum), not mounting\n");
2257                 goto fail;
2258         }
2259
2260         if (le32_to_cpu(data->sblock.revision_level) == 0)
2261                 fs->inodesz = 128;
2262         else
2263                 fs->inodesz = le16_to_cpu(data->sblock.inode_size);
2264
2265         debug("EXT2 rev %d, inode_size %d\n",
2266                le32_to_cpu(data->sblock.revision_level), fs->inodesz);
2267
2268         data->diropen.data = data;
2269         data->diropen.ino = 2;
2270         data->diropen.inode_read = 1;
2271         data->inode = &data->diropen.inode;
2272
2273         status = ext4fs_read_inode(data, 2, data->inode);
2274         if (status == 0)
2275                 goto fail;
2276
2277         ext4fs_root = data;
2278
2279         return 1;
2280 fail:
2281         printf("Failed to mount ext2 filesystem...\n");
2282         free(data);
2283         ext4fs_root = NULL;
2284
2285         return 0;
2286 }