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 struct ext2_block_group *ext4fs_get_group_descriptor
  51         (const struct ext_filesystem *fs, uint32_t bg_idx)
  52 {
  53         return (struct ext2_block_group *)(fs->gdtable + (bg_idx * fs->gdsize));
  54 }
  55
  56 static inline void ext4fs_sb_free_inodes_dec(struct ext2_sblock *sb)
  57 {
  58         sb->free_inodes = cpu_to_le32(le32_to_cpu(sb->free_inodes) - 1);
  59 }
  60
  61 static inline void ext4fs_sb_free_blocks_dec(struct ext2_sblock *sb)
  62 {
  63         uint64_t free_blocks = le32_to_cpu(sb->free_blocks);
  64         free_blocks += (uint64_t)le32_to_cpu(sb->free_blocks_high) << 32;
  65         free_blocks--;
  66
  67         sb->free_blocks = cpu_to_le32(free_blocks & 0xffffffff);
  68         sb->free_blocks_high = cpu_to_le16(free_blocks >> 32);
  69 }
  70
  71 static inline void ext4fs_bg_free_inodes_dec
  72         (struct ext2_block_group *bg, const struct ext_filesystem *fs)
  73 {
  74         uint32_t free_inodes = le16_to_cpu(bg->free_inodes);
  75         if (fs->gdsize == 64)
  76                 free_inodes += le16_to_cpu(bg->free_inodes_high) << 16;
  77         free_inodes--;
  78
  79         bg->free_inodes = cpu_to_le16(free_inodes & 0xffff);
  80         if (fs->gdsize == 64)
  81                 bg->free_inodes_high = cpu_to_le16(free_inodes >> 16);
  82 }
  83
  84 static inline void ext4fs_bg_free_blocks_dec
  85         (struct ext2_block_group *bg, const struct ext_filesystem *fs)
  86 {
  87         uint32_t free_blocks = le16_to_cpu(bg->free_blocks);
  88         if (fs->gdsize == 64)
  89                 free_blocks += le16_to_cpu(bg->free_blocks_high) << 16;
  90         free_blocks--;
  91
  92         bg->free_blocks = cpu_to_le16(free_blocks & 0xffff);
  93         if (fs->gdsize == 64)
  94                 bg->free_blocks_high = cpu_to_le16(free_blocks >> 16);
  95 }
  96
  97 static inline void ext4fs_bg_itable_unused_dec
  98         (struct ext2_block_group *bg, const struct ext_filesystem *fs)
  99 {
 100         uint32_t free_inodes = le16_to_cpu(bg->bg_itable_unused);
 101         if (fs->gdsize == 64)
 102                 free_inodes += le16_to_cpu(bg->bg_itable_unused_high) << 16;
 103         free_inodes--;
 104
 105         bg->bg_itable_unused = cpu_to_le16(free_inodes & 0xffff);
 106         if (fs->gdsize == 64)
 107                 bg->bg_itable_unused_high = cpu_to_le16(free_inodes >> 16);
 108 }
 109
 110 uint64_t ext4fs_sb_get_free_blocks(const struct ext2_sblock *sb)
 111 {
 112         uint64_t free_blocks = le32_to_cpu(sb->free_blocks);
 113         free_blocks += (uint64_t)le32_to_cpu(sb->free_blocks_high) << 32;
 114         return free_blocks;
 115 }
 116
 117 void ext4fs_sb_set_free_blocks(struct ext2_sblock *sb, uint64_t free_blocks)
 118 {
 119         sb->free_blocks = cpu_to_le32(free_blocks & 0xffffffff);
 120         sb->free_blocks_high = cpu_to_le16(free_blocks >> 32);
 121 }
 122
 123 uint32_t ext4fs_bg_get_free_blocks(const struct ext2_block_group *bg,
 124                                    const struct ext_filesystem *fs)
 125 {
 126         uint32_t free_blocks = le16_to_cpu(bg->free_blocks);
 127         if (fs->gdsize == 64)
 128                 free_blocks += le16_to_cpu(bg->free_blocks_high) << 16;
 129         return free_blocks;
 130 }
 131
 132 static inline
 133 uint32_t ext4fs_bg_get_free_inodes(const struct ext2_block_group *bg,
 134                                    const struct ext_filesystem *fs)
 135 {
 136         uint32_t free_inodes = le16_to_cpu(bg->free_inodes);
 137         if (fs->gdsize == 64)
 138                 free_inodes += le16_to_cpu(bg->free_inodes_high) << 16;
 139         return free_inodes;
 140 }
 141
 142 static inline uint16_t ext4fs_bg_get_flags(const struct ext2_block_group *bg)
 143 {
 144         return le16_to_cpu(bg->bg_flags);
 145 }
 146
 147 static inline void ext4fs_bg_set_flags(struct ext2_block_group *bg,
 148                                        uint16_t flags)
 149 {
 150         bg->bg_flags = cpu_to_le16(flags);
 151 }
 152
 153 /* Block number of the block bitmap */
 154 uint64_t ext4fs_bg_get_block_id(const struct ext2_block_group *bg,
 155                                 const struct ext_filesystem *fs)
 156 {
 157         uint64_t block_nr = le32_to_cpu(bg->block_id);
 158         if (fs->gdsize == 64)
 159                 block_nr += (uint64_t)le32_to_cpu(bg->block_id_high) << 32;
 160         return block_nr;
 161 }
 162
 163 /* Block number of the inode bitmap */
 164 uint64_t ext4fs_bg_get_inode_id(const struct ext2_block_group *bg,
 165                                 const struct ext_filesystem *fs)
 166 {
 167         uint64_t block_nr = le32_to_cpu(bg->inode_id);
 168         if (fs->gdsize == 64)
 169                 block_nr += (uint64_t)le32_to_cpu(bg->inode_id_high) << 32;
 170         return block_nr;
 171 }
 172 #endif
 173
 174 /* Block number of the inode table */
 175 uint64_t ext4fs_bg_get_inode_table_id(const struct ext2_block_group *bg,
 176                                       const struct ext_filesystem *fs)
 177 {
 178         uint64_t block_nr = le32_to_cpu(bg->inode_table_id);
 179         if (fs->gdsize == 64)
 180                 block_nr +=
 181                         (uint64_t)le32_to_cpu(bg->inode_table_id_high) << 32;
 182         return block_nr;
 183 }
 184
 185 #if defined(CONFIG_EXT4_WRITE)
 186 uint32_t ext4fs_div_roundup(uint32_t size, uint32_t n)
 187 {
 188         uint32_t res = size / n;
 189         if (res * n != size)
 190                 res++;
 191
 192         return res;
 193 }
 194
 195 void put_ext4(uint64_t off, void *buf, uint32_t size)
 196 {
 197         uint64_t startblock;
 198         uint64_t remainder;
 199         unsigned char *temp_ptr = NULL;
 200         struct ext_filesystem *fs = get_fs();
 201         int log2blksz = fs->dev_desc->log2blksz;
 202         ALLOC_CACHE_ALIGN_BUFFER(unsigned char, sec_buf, fs->dev_desc->blksz);
 203
 204         startblock = off >> log2blksz;
 205         startblock += part_offset;
 206         remainder = off & (uint64_t)(fs->dev_desc->blksz - 1);
 207
 208         if (fs->dev_desc == NULL)
 209                 return;
 210
 211         if ((startblock + (size >> log2blksz)) >
 212             (part_offset + fs->total_sect)) {
 213                 printf("part_offset is " LBAFU "\n", part_offset);
 214                 printf("total_sector is %" PRIu64 "\n", fs->total_sect);
 215                 printf("error: overflow occurs\n");
 216                 return;
 217         }
 218
 219         if (remainder) {
 220                 blk_dread(fs->dev_desc, startblock, 1, sec_buf);
 221                 temp_ptr = sec_buf;
 222                 memcpy((temp_ptr + remainder), (unsigned char *)buf, size);
 223                 blk_dwrite(fs->dev_desc, startblock, 1, sec_buf);
 224         } else {
 225                 if (size >> log2blksz != 0) {
 226                         blk_dwrite(fs->dev_desc, startblock, size >> log2blksz,
 227                                    (unsigned long *)buf);
 228                 } else {
 229                         blk_dread(fs->dev_desc, startblock, 1, sec_buf);
 230                         temp_ptr = sec_buf;
 231                         memcpy(temp_ptr, buf, size);
 232                         blk_dwrite(fs->dev_desc, startblock, 1,
 233                                    (unsigned long *)sec_buf);
 234                 }
 235         }
 236 }
 237
 238 static int _get_new_inode_no(unsigned char *buffer)
 239 {
 240         struct ext_filesystem *fs = get_fs();
 241         unsigned char input;
 242         int operand, status;
 243         int count = 1;
 244         int j = 0;
 245
 246         /* get the blocksize of the filesystem */
 247         unsigned char *ptr = buffer;
 248         while (*ptr == 255) {
 249                 ptr++;
 250                 count += 8;
 251                 if (count > le32_to_cpu(ext4fs_root->sblock.inodes_per_group))
 252                         return -1;
 253         }
 254
 255         for (j = 0; j < fs->blksz; j++) {
 256                 input = *ptr;
 257                 int i = 0;
 258                 while (i <= 7) {
 259                         operand = 1 << i;
 260                         status = input & operand;
 261                         if (status) {
 262                                 i++;
 263                                 count++;
 264                         } else {
 265                                 *ptr |= operand;
 266                                 return count;
 267                         }
 268                 }
 269                 ptr = ptr + 1;
 270         }
 271
 272         return -1;
 273 }
 274
 275 static int _get_new_blk_no(unsigned char *buffer)
 276 {
 277         int operand;
 278         int count = 0;
 279         int i;
 280         unsigned char *ptr = buffer;
 281         struct ext_filesystem *fs = get_fs();
 282
 283         while (*ptr == 255) {
 284                 ptr++;
 285                 count += 8;
 286                 if (count == (fs->blksz * 8))
 287                         return -1;
 288         }
 289
 290         if (fs->blksz == 1024)
 291                 count += 1;
 292
 293         for (i = 0; i <= 7; i++) {
 294                 operand = 1 << i;
 295                 if (*ptr & operand) {
 296                         count++;
 297                 } else {
 298                         *ptr |= operand;
 299                         return count;
 300                 }
 301         }
 302
 303         return -1;
 304 }
 305
 306 int ext4fs_set_block_bmap(long int blockno, unsigned char *buffer, int index)
 307 {
 308         int i, remainder, status;
 309         unsigned char *ptr = buffer;
 310         unsigned char operand;
 311         i = blockno / 8;
 312         remainder = blockno % 8;
 313         int blocksize = EXT2_BLOCK_SIZE(ext4fs_root);
 314
 315         i = i - (index * blocksize);
 316         if (blocksize != 1024) {
 317                 ptr = ptr + i;
 318                 operand = 1 << remainder;
 319                 status = *ptr & operand;
 320                 if (status)
 321                         return -1;
 322
 323                 *ptr = *ptr | operand;
 324                 return 0;
 325         } else {
 326                 if (remainder == 0) {
 327                         ptr = ptr + i - 1;
 328                         operand = (1 << 7);
 329                 } else {
 330                         ptr = ptr + i;
 331                         operand = (1 << (remainder - 1));
 332                 }
 333                 status = *ptr & operand;
 334                 if (status)
 335                         return -1;
 336
 337                 *ptr = *ptr | operand;
 338                 return 0;
 339         }
 340 }
 341
 342 void ext4fs_reset_block_bmap(long int blockno, unsigned char *buffer, int index)
 343 {
 344         int i, remainder, status;
 345         unsigned char *ptr = buffer;
 346         unsigned char operand;
 347         i = blockno / 8;
 348         remainder = blockno % 8;
 349         int blocksize = EXT2_BLOCK_SIZE(ext4fs_root);
 350
 351         i = i - (index * blocksize);
 352         if (blocksize != 1024) {
 353                 ptr = ptr + i;
 354                 operand = (1 << remainder);
 355                 status = *ptr & operand;
 356                 if (status)
 357                         *ptr = *ptr & ~(operand);
 358         } else {
 359                 if (remainder == 0) {
 360                         ptr = ptr + i - 1;
 361                         operand = (1 << 7);
 362                 } else {
 363                         ptr = ptr + i;
 364                         operand = (1 << (remainder - 1));
 365                 }
 366                 status = *ptr & operand;
 367                 if (status)
 368                         *ptr = *ptr & ~(operand);
 369         }
 370 }
 371
 372 int ext4fs_set_inode_bmap(int inode_no, unsigned char *buffer, int index)
 373 {
 374         int i, remainder, status;
 375         unsigned char *ptr = buffer;
 376         unsigned char operand;
 377
 378         inode_no -= (index * le32_to_cpu(ext4fs_root->sblock.inodes_per_group));
 379         i = inode_no / 8;
 380         remainder = inode_no % 8;
 381         if (remainder == 0) {
 382                 ptr = ptr + i - 1;
 383                 operand = (1 << 7);
 384         } else {
 385                 ptr = ptr + i;
 386                 operand = (1 << (remainder - 1));
 387         }
 388         status = *ptr & operand;
 389         if (status)
 390                 return -1;
 391
 392         *ptr = *ptr | operand;
 393
 394         return 0;
 395 }
 396
 397 void ext4fs_reset_inode_bmap(int inode_no, unsigned char *buffer, int index)
 398 {
 399         int i, remainder, status;
 400         unsigned char *ptr = buffer;
 401         unsigned char operand;
 402
 403         inode_no -= (index * le32_to_cpu(ext4fs_root->sblock.inodes_per_group));
 404         i = inode_no / 8;
 405         remainder = inode_no % 8;
 406         if (remainder == 0) {
 407                 ptr = ptr + i - 1;
 408                 operand = (1 << 7);
 409         } else {
 410                 ptr = ptr + i;
 411                 operand = (1 << (remainder - 1));
 412         }
 413         status = *ptr & operand;
 414         if (status)
 415                 *ptr = *ptr & ~(operand);
 416 }
 417
 418 uint16_t ext4fs_checksum_update(uint32_t i)
 419 {
 420         struct ext2_block_group *desc;
 421         struct ext_filesystem *fs = get_fs();
 422         uint16_t crc = 0;
 423         __le32 le32_i = cpu_to_le32(i);
 424
 425         desc = ext4fs_get_group_descriptor(fs, i);
 426         if (le32_to_cpu(fs->sb->feature_ro_compat) & EXT4_FEATURE_RO_COMPAT_GDT_CSUM) {
 427                 int offset = offsetof(struct ext2_block_group, bg_checksum);
 428
 429                 crc = ext2fs_crc16(~0, fs->sb->unique_id,
 430                                    sizeof(fs->sb->unique_id));
 431                 crc = ext2fs_crc16(crc, &le32_i, sizeof(le32_i));
 432                 crc = ext2fs_crc16(crc, desc, offset);
 433                 offset += sizeof(desc->bg_checksum);    /* skip checksum */
 434                 assert(offset == sizeof(*desc));
 435         }
 436
 437         return crc;
 438 }
 439
 440 static int check_void_in_dentry(struct ext2_dirent *dir, char *filename)
 441 {
 442         int dentry_length;
 443         int sizeof_void_space;
 444         int new_entry_byte_reqd;
 445         short padding_factor = 0;
 446
 447         if (dir->namelen % 4 != 0)
 448                 padding_factor = 4 - (dir->namelen % 4);
 449
 450         dentry_length = sizeof(struct ext2_dirent) +
 451                         dir->namelen + padding_factor;
 452         sizeof_void_space = le16_to_cpu(dir->direntlen) - dentry_length;
 453         if (sizeof_void_space == 0)
 454                 return 0;
 455
 456         padding_factor = 0;
 457         if (strlen(filename) % 4 != 0)
 458                 padding_factor = 4 - (strlen(filename) % 4);
 459
 460         new_entry_byte_reqd = strlen(filename) +
 461             sizeof(struct ext2_dirent) + padding_factor;
 462         if (sizeof_void_space >= new_entry_byte_reqd) {
 463                 dir->direntlen = cpu_to_le16(dentry_length);
 464                 return sizeof_void_space;
 465         }
 466
 467         return 0;
 468 }
 469
 470 int ext4fs_update_parent_dentry(char *filename, int file_type)
 471 {
 472         unsigned int *zero_buffer = NULL;
 473         char *root_first_block_buffer = NULL;
 474         int blk_idx;
 475         long int first_block_no_of_root = 0;
 476         int totalbytes = 0;
 477         unsigned int new_entry_byte_reqd;
 478         int sizeof_void_space = 0;
 479         int templength = 0;
 480         int inodeno = -1;
 481         int status;
 482         struct ext_filesystem *fs = get_fs();
 483         /* directory entry */
 484         struct ext2_dirent *dir;
 485         char *temp_dir = NULL;
 486         uint32_t new_blk_no;
 487         uint32_t new_size;
 488         uint32_t new_blockcnt;
 489         uint32_t directory_blocks;
 490
 491         zero_buffer = zalloc(fs->blksz);
 492         if (!zero_buffer) {
 493                 printf("No Memory\n");
 494                 return -1;
 495         }
 496         root_first_block_buffer = zalloc(fs->blksz);
 497         if (!root_first_block_buffer) {
 498                 free(zero_buffer);
 499                 printf("No Memory\n");
 500                 return -1;
 501         }
 502         new_entry_byte_reqd = ROUND(strlen(filename) +
 503                                     sizeof(struct ext2_dirent), 4);
 504 restart:
 505         directory_blocks = le32_to_cpu(g_parent_inode->size) >>
 506                 LOG2_BLOCK_SIZE(ext4fs_root);
 507         blk_idx = directory_blocks - 1;
 508
 509 restart_read:
 510         /* read the block no allocated to a file */
 511         first_block_no_of_root = read_allocated_block(g_parent_inode, blk_idx);
 512         if (first_block_no_of_root <= 0)
 513                 goto fail;
 514
 515         status = ext4fs_devread((lbaint_t)first_block_no_of_root
 516                                 * fs->sect_perblk,
 517                                 0, fs->blksz, root_first_block_buffer);
 518         if (status == 0)
 519                 goto fail;
 520
 521         if (ext4fs_log_journal(root_first_block_buffer, first_block_no_of_root))
 522                 goto fail;
 523         dir = (struct ext2_dirent *)root_first_block_buffer;
 524         totalbytes = 0;
 525
 526         while (le16_to_cpu(dir->direntlen) > 0) {
 527                 unsigned short used_len = ROUND(dir->namelen +
 528                     sizeof(struct ext2_dirent), 4);
 529
 530                 /* last entry of block */
 531                 if (fs->blksz - totalbytes == le16_to_cpu(dir->direntlen)) {
 532
 533                         /* check if new entry fits */
 534                         if ((used_len + new_entry_byte_reqd) <=
 535                             le16_to_cpu(dir->direntlen)) {
 536                                 dir->direntlen = cpu_to_le16(used_len);
 537                                 break;
 538                         } else {
 539                                 if (blk_idx > 0) {
 540                                         printf("Block full, trying previous\n");
 541                                         blk_idx--;
 542                                         goto restart_read;
 543                                 }
 544                                 printf("All blocks full: Allocate new\n");
 545
 546                                 if (le32_to_cpu(g_parent_inode->flags) &
 547                                                 EXT4_EXTENTS_FL) {
 548                                         printf("Directory uses extents\n");
 549                                         goto fail;
 550                                 }
 551                                 if (directory_blocks >= INDIRECT_BLOCKS) {
 552                                         printf("Directory exceeds limit\n");
 553                                         goto fail;
 554                                 }
 555                                 new_blk_no = ext4fs_get_new_blk_no();
 556                                 if (new_blk_no == -1) {
 557                                         printf("no block left to assign\n");
 558                                         goto fail;
 559                                 }
 560                                 put_ext4((uint64_t)new_blk_no * fs->blksz, zero_buffer, fs->blksz);
 561                                 g_parent_inode->b.blocks.
 562                                         dir_blocks[directory_blocks] =
 563                                         cpu_to_le32(new_blk_no);
 564
 565                                 new_size = le32_to_cpu(g_parent_inode->size);
 566                                 new_size += fs->blksz;
 567                                 g_parent_inode->size = cpu_to_le32(new_size);
 568
 569                                 new_blockcnt = le32_to_cpu(g_parent_inode->blockcnt);
 570                                 new_blockcnt += fs->sect_perblk;
 571                                 g_parent_inode->blockcnt = cpu_to_le32(new_blockcnt);
 572
 573                                 if (ext4fs_put_metadata
 574                                     (root_first_block_buffer,
 575                                      first_block_no_of_root))
 576                                         goto fail;
 577                                 goto restart;
 578                         }
 579                 }
 580
 581                 templength = le16_to_cpu(dir->direntlen);
 582                 totalbytes = totalbytes + templength;
 583                 sizeof_void_space = check_void_in_dentry(dir, filename);
 584                 if (sizeof_void_space)
 585                         break;
 586
 587                 dir = (struct ext2_dirent *)((char *)dir + templength);
 588         }
 589
 590         /* make a pointer ready for creating next directory entry */
 591         templength = le16_to_cpu(dir->direntlen);
 592         totalbytes = totalbytes + templength;
 593         dir = (struct ext2_dirent *)((char *)dir + templength);
 594
 595         /* get the next available inode number */
 596         inodeno = ext4fs_get_new_inode_no();
 597         if (inodeno == -1) {
 598                 printf("no inode left to assign\n");
 599                 goto fail;
 600         }
 601         dir->inode = cpu_to_le32(inodeno);
 602         if (sizeof_void_space)
 603                 dir->direntlen = cpu_to_le16(sizeof_void_space);
 604         else
 605                 dir->direntlen = cpu_to_le16(fs->blksz - totalbytes);
 606
 607         dir->namelen = strlen(filename);
 608         dir->filetype = FILETYPE_REG;   /* regular file */
 609         temp_dir = (char *)dir;
 610         temp_dir = temp_dir + sizeof(struct ext2_dirent);
 611         memcpy(temp_dir, filename, strlen(filename));
 612
 613         /* update or write  the 1st block of root inode */
 614         if (ext4fs_put_metadata(root_first_block_buffer,
 615                                 first_block_no_of_root))
 616                 goto fail;
 617
 618 fail:
 619         free(zero_buffer);
 620         free(root_first_block_buffer);
 621
 622         return inodeno;
 623 }
 624
 625 static int search_dir(struct ext2_inode *parent_inode, char *dirname)
 626 {
 627         int status;
 628         int inodeno = 0;
 629         int offset;
 630         int blk_idx;
 631         long int blknr;
 632         char *block_buffer = NULL;
 633         struct ext2_dirent *dir = NULL;
 634         struct ext_filesystem *fs = get_fs();
 635         uint32_t directory_blocks;
 636         char *direntname;
 637
 638         directory_blocks = le32_to_cpu(parent_inode->size) >>
 639                 LOG2_BLOCK_SIZE(ext4fs_root);
 640
 641         block_buffer = zalloc(fs->blksz);
 642         if (!block_buffer)
 643                 goto fail;
 644
 645         /* get the block no allocated to a file */
 646         for (blk_idx = 0; blk_idx < directory_blocks; blk_idx++) {
 647                 blknr = read_allocated_block(parent_inode, blk_idx);
 648                 if (blknr <= 0)
 649                         goto fail;
 650
 651                 /* read the directory block */
 652                 status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk,
 653                                         0, fs->blksz, (char *)block_buffer);
 654                 if (status == 0)
 655                         goto fail;
 656
 657                 offset = 0;
 658                 do {
 659                         dir = (struct ext2_dirent *)(block_buffer + offset);
 660                         direntname = (char*)(dir) + sizeof(struct ext2_dirent);
 661
 662                         int direntlen = le16_to_cpu(dir->direntlen);
 663                         if (direntlen < sizeof(struct ext2_dirent))
 664                                 break;
 665
 666                         if (dir->inode && (strlen(dirname) == dir->namelen) &&
 667                             (strncmp(dirname, direntname, dir->namelen) == 0)) {
 668                                 inodeno = le32_to_cpu(dir->inode);
 669                                 break;
 670                         }
 671
 672                         offset += direntlen;
 673
 674                 } while (offset < fs->blksz);
 675
 676                 if (inodeno > 0) {
 677                         free(block_buffer);
 678                         return inodeno;
 679                 }
 680         }
 681
 682 fail:
 683         free(block_buffer);
 684
 685         return -1;
 686 }
 687
 688 static int find_dir_depth(char *dirname)
 689 {
 690         char *token = strtok(dirname, "/");
 691         int count = 0;
 692         while (token != NULL) {
 693                 token = strtok(NULL, "/");
 694                 count++;
 695         }
 696         return count + 1 + 1;
 697         /*
 698          * for example  for string /home/temp
 699          * depth=home(1)+temp(1)+1 extra for NULL;
 700          * so count is 4;
 701          */
 702 }
 703
 704 static int parse_path(char **arr, char *dirname)
 705 {
 706         char *token = strtok(dirname, "/");
 707         int i = 0;
 708
 709         /* add root */
 710         arr[i] = zalloc(strlen("/") + 1);
 711         if (!arr[i])
 712                 return -ENOMEM;
 713         memcpy(arr[i++], "/", strlen("/"));
 714
 715         /* add each path entry after root */
 716         while (token != NULL) {
 717                 arr[i] = zalloc(strlen(token) + 1);
 718                 if (!arr[i])
 719                         return -ENOMEM;
 720                 memcpy(arr[i++], token, strlen(token));
 721                 token = strtok(NULL, "/");
 722         }
 723         arr[i] = NULL;
 724
 725         return 0;
 726 }
 727
 728 int ext4fs_iget(int inode_no, struct ext2_inode *inode)
 729 {
 730         if (ext4fs_read_inode(ext4fs_root, inode_no, inode) == 0)
 731                 return -1;
 732
 733         return 0;
 734 }
 735
 736 /*
 737  * Function: ext4fs_get_parent_inode_num
 738  * Return Value: inode Number of the parent directory of  file/Directory to be
 739  * created
 740  * dirname : Input parmater, input path name of the file/directory to be created
 741  * dname : Output parameter, to be filled with the name of the directory
 742  * extracted from dirname
 743  */
 744 int ext4fs_get_parent_inode_num(const char *dirname, char *dname, int flags)
 745 {
 746         int i;
 747         int depth = 0;
 748         int matched_inode_no;
 749         int result_inode_no = -1;
 750         char **ptr = NULL;
 751         char *depth_dirname = NULL;
 752         char *parse_dirname = NULL;
 753         struct ext2_inode *parent_inode = NULL;
 754         struct ext2_inode *first_inode = NULL;
 755         struct ext2_inode temp_inode;
 756
 757         if (*dirname != '/') {
 758                 printf("Please supply Absolute path\n");
 759                 return -1;
 760         }
 761
 762         /* TODO: input validation make equivalent to linux */
 763         depth_dirname = zalloc(strlen(dirname) + 1);
 764         if (!depth_dirname)
 765                 return -ENOMEM;
 766
 767         memcpy(depth_dirname, dirname, strlen(dirname));
 768         depth = find_dir_depth(depth_dirname);
 769         parse_dirname = zalloc(strlen(dirname) + 1);
 770         if (!parse_dirname)
 771                 goto fail;
 772         memcpy(parse_dirname, dirname, strlen(dirname));
 773
 774         /* allocate memory for each directory level */
 775         ptr = zalloc((depth) * sizeof(char *));
 776         if (!ptr)
 777                 goto fail;
 778         if (parse_path(ptr, parse_dirname))
 779                 goto fail;
 780         parent_inode = zalloc(sizeof(struct ext2_inode));
 781         if (!parent_inode)
 782                 goto fail;
 783         first_inode = zalloc(sizeof(struct ext2_inode));
 784         if (!first_inode)
 785                 goto fail;
 786         memcpy(parent_inode, ext4fs_root->inode, sizeof(struct ext2_inode));
 787         memcpy(first_inode, parent_inode, sizeof(struct ext2_inode));
 788         if (flags & F_FILE)
 789                 result_inode_no = EXT2_ROOT_INO;
 790         for (i = 1; i < depth; i++) {
 791                 matched_inode_no = search_dir(parent_inode, ptr[i]);
 792                 if (matched_inode_no == -1) {
 793                         if (ptr[i + 1] == NULL && i == 1) {
 794                                 result_inode_no = EXT2_ROOT_INO;
 795                                 goto end;
 796                         } else {
 797                                 if (ptr[i + 1] == NULL)
 798                                         break;
 799                                 printf("Invalid path\n");
 800                                 result_inode_no = -1;
 801                                 goto fail;
 802                         }
 803                 } else {
 804                         if (ptr[i + 1] != NULL) {
 805                                 memset(parent_inode, '\0',
 806                                        sizeof(struct ext2_inode));
 807                                 if (ext4fs_iget(matched_inode_no,
 808                                                 parent_inode)) {
 809                                         result_inode_no = -1;
 810                                         goto fail;
 811                                 }
 812                                 result_inode_no = matched_inode_no;
 813                         } else {
 814                                 break;
 815                         }
 816                 }
 817         }
 818
 819 end:
 820         if (i == 1)
 821                 matched_inode_no = search_dir(first_inode, ptr[i]);
 822         else
 823                 matched_inode_no = search_dir(parent_inode, ptr[i]);
 824
 825         if (matched_inode_no != -1) {
 826                 ext4fs_iget(matched_inode_no, &temp_inode);
 827                 if (le16_to_cpu(temp_inode.mode) & S_IFDIR) {
 828                         printf("It is a Directory\n");
 829                         result_inode_no = -1;
 830                         goto fail;
 831                 }
 832         }
 833
 834         if (strlen(ptr[i]) > 256) {
 835                 result_inode_no = -1;
 836                 goto fail;
 837         }
 838         memcpy(dname, ptr[i], strlen(ptr[i]));
 839
 840 fail:
 841         free(depth_dirname);
 842         free(parse_dirname);
 843         for (i = 0; i < depth; i++) {
 844                 if (!ptr[i])
 845                         break;
 846                 free(ptr[i]);
 847         }
 848         free(ptr);
 849         free(parent_inode);
 850         free(first_inode);
 851
 852         return result_inode_no;
 853 }
 854
 855 static int unlink_filename(char *filename, unsigned int blknr)
 856 {
 857         int templength = 0;
 858         int status, inodeno;
 859         int found = 0;
 860         int offset;
 861         char *block_buffer = NULL;
 862         struct ext2_dirent *dir = NULL;
 863         struct ext2_dirent *previous_dir = NULL;
 864         char *ptr = NULL;
 865         struct ext_filesystem *fs = get_fs();
 866         int ret = -1;
 867
 868         block_buffer = zalloc(fs->blksz);
 869         if (!block_buffer)
 870                 return -ENOMEM;
 871
 872         /* read the directory block */
 873         status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 0,
 874                                 fs->blksz, block_buffer);
 875         if (status == 0)
 876                 goto fail;
 877
 878         if (ext4fs_log_journal(block_buffer, blknr))
 879                 goto fail;
 880         dir = (struct ext2_dirent *)block_buffer;
 881         ptr = (char *)dir;
 882         offset = 0;
 883         while (le16_to_cpu(dir->direntlen) >= 0) {
 884                 /*
 885                  * blocksize-offset because last
 886                  * directory length i.e., *dir->direntlen
 887                  * is free availble space in the block that
 888                  * means it is a last entry of directory entry
 889                  */
 890                 if (dir->inode && (strlen(filename) == dir->namelen) &&
 891                     (strncmp(ptr + sizeof(struct ext2_dirent),
 892                              filename, dir->namelen) == 0)) {
 893                         printf("file found, deleting\n");
 894                         inodeno = le32_to_cpu(dir->inode);
 895                         if (previous_dir) {
 896                                 uint16_t new_len;
 897                                 new_len = le16_to_cpu(previous_dir->direntlen);
 898                                 new_len += le16_to_cpu(dir->direntlen);
 899                                 previous_dir->direntlen = cpu_to_le16(new_len);
 900                         } else {
 901                                 dir->inode = 0;
 902                         }
 903                         found = 1;
 904                         break;
 905                 }
 906
 907                 if (fs->blksz - offset == le16_to_cpu(dir->direntlen))
 908                         break;
 909
 910                 /* traversing the each directory entry */
 911                 templength = le16_to_cpu(dir->direntlen);
 912                 offset = offset + templength;
 913                 previous_dir = dir;
 914                 dir = (struct ext2_dirent *)((char *)dir + templength);
 915                 ptr = (char *)dir;
 916         }
 917
 918
 919         if (found == 1) {
 920                 if (ext4fs_put_metadata(block_buffer, blknr))
 921                         goto fail;
 922                 ret = inodeno;
 923         }
 924 fail:
 925         free(block_buffer);
 926
 927         return ret;
 928 }
 929
 930 int ext4fs_filename_unlink(char *filename)
 931 {
 932         int blk_idx;
 933         long int blknr = -1;
 934         int inodeno = -1;
 935         uint32_t directory_blocks;
 936
 937         directory_blocks = le32_to_cpu(g_parent_inode->size) >>
 938                 LOG2_BLOCK_SIZE(ext4fs_root);
 939
 940         /* read the block no allocated to a file */
 941         for (blk_idx = 0; blk_idx < directory_blocks; blk_idx++) {
 942                 blknr = read_allocated_block(g_parent_inode, blk_idx);
 943                 if (blknr <= 0)
 944                         break;
 945                 inodeno = unlink_filename(filename, blknr);
 946                 if (inodeno != -1)
 947                         return inodeno;
 948         }
 949
 950         return -1;
 951 }
 952
 953 uint32_t ext4fs_get_new_blk_no(void)
 954 {
 955         short i;
 956         short status;
 957         int remainder;
 958         unsigned int bg_idx;
 959         static int prev_bg_bitmap_index = -1;
 960         unsigned int blk_per_grp = le32_to_cpu(ext4fs_root->sblock.blocks_per_group);
 961         struct ext_filesystem *fs = get_fs();
 962         char *journal_buffer = zalloc(fs->blksz);
 963         char *zero_buffer = zalloc(fs->blksz);
 964         if (!journal_buffer || !zero_buffer)
 965                 goto fail;
 966
 967         if (fs->first_pass_bbmap == 0) {
 968                 for (i = 0; i < fs->no_blkgrp; i++) {
 969                         struct ext2_block_group *bgd = NULL;
 970                         bgd = ext4fs_get_group_descriptor(fs, i);
 971                         if (ext4fs_bg_get_free_blocks(bgd, fs)) {
 972                                 uint16_t bg_flags = ext4fs_bg_get_flags(bgd);
 973                                 uint64_t b_bitmap_blk =
 974                                         ext4fs_bg_get_block_id(bgd, fs);
 975                                 if (bg_flags & EXT4_BG_BLOCK_UNINIT) {
 976                                         memcpy(fs->blk_bmaps[i], zero_buffer,
 977                                                fs->blksz);
 978                                         put_ext4(b_bitmap_blk * fs->blksz,
 979                                                  fs->blk_bmaps[i], fs->blksz);
 980                                         bg_flags &= ~EXT4_BG_BLOCK_UNINIT;
 981                                         ext4fs_bg_set_flags(bgd, bg_flags);
 982                                 }
 983                                 fs->curr_blkno =
 984                                     _get_new_blk_no(fs->blk_bmaps[i]);
 985                                 if (fs->curr_blkno == -1)
 986                                         /* block bitmap is completely filled */
 987                                         continue;
 988                                 fs->curr_blkno = fs->curr_blkno +
 989                                                 (i * fs->blksz * 8);
 990                                 fs->first_pass_bbmap++;
 991                                 ext4fs_bg_free_blocks_dec(bgd, fs);
 992                                 ext4fs_sb_free_blocks_dec(fs->sb);
 993                                 status = ext4fs_devread(b_bitmap_blk *
 994                                                         fs->sect_perblk,
 995                                                         0, fs->blksz,
 996                                                         journal_buffer);
 997                                 if (status == 0)
 998                                         goto fail;
 999                                 if (ext4fs_log_journal(journal_buffer,
1000                                                        b_bitmap_blk))
1001                                         goto fail;
1002                                 goto success;
1003                         } else {
1004                                 debug("no space left on block group %d\n", i);
1005                         }
1006                 }
1007
1008                 goto fail;
1009         } else {
1010                 fs->curr_blkno++;
1011 restart:
1012                 /* get the blockbitmap index respective to blockno */
1013                 bg_idx = fs->curr_blkno / blk_per_grp;
1014                 if (fs->blksz == 1024) {
1015                         remainder = fs->curr_blkno % blk_per_grp;
1016                         if (!remainder)
1017                                 bg_idx--;
1018                 }
1019
1020                 /*
1021                  * To skip completely filled block group bitmaps
1022                  * Optimize the block allocation
1023                  */
1024                 if (bg_idx >= fs->no_blkgrp)
1025                         goto fail;
1026
1027                 struct ext2_block_group *bgd = NULL;
1028                 bgd = ext4fs_get_group_descriptor(fs, bg_idx);
1029                 if (ext4fs_bg_get_free_blocks(bgd, fs) == 0) {
1030                         debug("block group %u is full. Skipping\n", bg_idx);
1031                         fs->curr_blkno = (bg_idx + 1) * blk_per_grp;
1032                         if (fs->blksz == 1024)
1033                                 fs->curr_blkno += 1;
1034                         goto restart;
1035                 }
1036
1037                 uint16_t bg_flags = ext4fs_bg_get_flags(bgd);
1038                 uint64_t b_bitmap_blk = ext4fs_bg_get_block_id(bgd, fs);
1039                 if (bg_flags & EXT4_BG_BLOCK_UNINIT) {
1040                         memcpy(fs->blk_bmaps[bg_idx], zero_buffer, fs->blksz);
1041                         put_ext4(b_bitmap_blk * fs->blksz,
1042                                  zero_buffer, fs->blksz);
1043                         bg_flags &= ~EXT4_BG_BLOCK_UNINIT;
1044                         ext4fs_bg_set_flags(bgd, bg_flags);
1045                 }
1046
1047                 if (ext4fs_set_block_bmap(fs->curr_blkno, fs->blk_bmaps[bg_idx],
1048                                    bg_idx) != 0) {
1049                         debug("going for restart for the block no %ld %u\n",
1050                               fs->curr_blkno, bg_idx);
1051                         fs->curr_blkno++;
1052                         goto restart;
1053                 }
1054
1055                 /* journal backup */
1056                 if (prev_bg_bitmap_index != bg_idx) {
1057                         status = ext4fs_devread(b_bitmap_blk * fs->sect_perblk,
1058                                                 0, fs->blksz, journal_buffer);
1059                         if (status == 0)
1060                                 goto fail;
1061                         if (ext4fs_log_journal(journal_buffer, b_bitmap_blk))
1062                                 goto fail;
1063
1064                         prev_bg_bitmap_index = bg_idx;
1065                 }
1066                 ext4fs_bg_free_blocks_dec(bgd, fs);
1067                 ext4fs_sb_free_blocks_dec(fs->sb);
1068                 goto success;
1069         }
1070 success:
1071         free(journal_buffer);
1072         free(zero_buffer);
1073
1074         return fs->curr_blkno;
1075 fail:
1076         free(journal_buffer);
1077         free(zero_buffer);
1078
1079         return -1;
1080 }
1081
1082 int ext4fs_get_new_inode_no(void)
1083 {
1084         short i;
1085         short status;
1086         unsigned int ibmap_idx;
1087         static int prev_inode_bitmap_index = -1;
1088         unsigned int inodes_per_grp = le32_to_cpu(ext4fs_root->sblock.inodes_per_group);
1089         struct ext_filesystem *fs = get_fs();
1090         char *journal_buffer = zalloc(fs->blksz);
1091         char *zero_buffer = zalloc(fs->blksz);
1092         if (!journal_buffer || !zero_buffer)
1093                 goto fail;
1094         int has_gdt_chksum = le32_to_cpu(fs->sb->feature_ro_compat) &
1095                 EXT4_FEATURE_RO_COMPAT_GDT_CSUM ? 1 : 0;
1096
1097         if (fs->first_pass_ibmap == 0) {
1098                 for (i = 0; i < fs->no_blkgrp; i++) {
1099                         uint32_t free_inodes;
1100                         struct ext2_block_group *bgd = NULL;
1101                         bgd = ext4fs_get_group_descriptor(fs, i);
1102                         free_inodes = ext4fs_bg_get_free_inodes(bgd, fs);
1103                         if (free_inodes) {
1104                                 uint16_t bg_flags = ext4fs_bg_get_flags(bgd);
1105                                 uint64_t i_bitmap_blk =
1106                                         ext4fs_bg_get_inode_id(bgd, fs);
1107                                 if (has_gdt_chksum)
1108                                         bgd->bg_itable_unused = free_inodes;
1109                                 if (bg_flags & EXT4_BG_INODE_UNINIT) {
1110                                         put_ext4(i_bitmap_blk * fs->blksz,
1111                                                  zero_buffer, fs->blksz);
1112                                         bg_flags &= ~EXT4_BG_INODE_UNINIT;
1113                                         ext4fs_bg_set_flags(bgd, bg_flags);
1114                                         memcpy(fs->inode_bmaps[i],
1115                                                zero_buffer, fs->blksz);
1116                                 }
1117                                 fs->curr_inode_no =
1118                                     _get_new_inode_no(fs->inode_bmaps[i]);
1119                                 if (fs->curr_inode_no == -1)
1120                                         /* inode bitmap is completely filled */
1121                                         continue;
1122                                 fs->curr_inode_no = fs->curr_inode_no +
1123                                                         (i * inodes_per_grp);
1124                                 fs->first_pass_ibmap++;
1125                                 ext4fs_bg_free_inodes_dec(bgd, fs);
1126                                 if (has_gdt_chksum)
1127                                         ext4fs_bg_itable_unused_dec(bgd, fs);
1128                                 ext4fs_sb_free_inodes_dec(fs->sb);
1129                                 status = ext4fs_devread(i_bitmap_blk *
1130                                                         fs->sect_perblk,
1131                                                         0, fs->blksz,
1132                                                         journal_buffer);
1133                                 if (status == 0)
1134                                         goto fail;
1135                                 if (ext4fs_log_journal(journal_buffer,
1136                                                        i_bitmap_blk))
1137                                         goto fail;
1138                                 goto success;
1139                         } else
1140                                 debug("no inode left on block group %d\n", i);
1141                 }
1142                 goto fail;
1143         } else {
1144 restart:
1145                 fs->curr_inode_no++;
1146                 /* get the blockbitmap index respective to blockno */
1147                 ibmap_idx = fs->curr_inode_no / inodes_per_grp;
1148                 struct ext2_block_group *bgd =
1149                         ext4fs_get_group_descriptor(fs, ibmap_idx);
1150                 uint16_t bg_flags = ext4fs_bg_get_flags(bgd);
1151                 uint64_t i_bitmap_blk = ext4fs_bg_get_inode_id(bgd, fs);
1152
1153                 if (bg_flags & EXT4_BG_INODE_UNINIT) {
1154                         put_ext4(i_bitmap_blk * fs->blksz,
1155                                  zero_buffer, fs->blksz);
1156                         bg_flags &= ~EXT4_BG_INODE_UNINIT;
1157                         ext4fs_bg_set_flags(bgd, bg_flags);
1158                         memcpy(fs->inode_bmaps[ibmap_idx], zero_buffer,
1159                                 fs->blksz);
1160                 }
1161
1162                 if (ext4fs_set_inode_bmap(fs->curr_inode_no,
1163                                           fs->inode_bmaps[ibmap_idx],
1164                                           ibmap_idx) != 0) {
1165                         debug("going for restart for the block no %d %u\n",
1166                               fs->curr_inode_no, ibmap_idx);
1167                         goto restart;
1168                 }
1169
1170                 /* journal backup */
1171                 if (prev_inode_bitmap_index != ibmap_idx) {
1172                         status = ext4fs_devread(i_bitmap_blk * fs->sect_perblk,
1173                                                 0, fs->blksz, journal_buffer);
1174                         if (status == 0)
1175                                 goto fail;
1176                         if (ext4fs_log_journal(journal_buffer,
1177                                                 le32_to_cpu(bgd->inode_id)))
1178                                 goto fail;
1179                         prev_inode_bitmap_index = ibmap_idx;
1180                 }
1181                 ext4fs_bg_free_inodes_dec(bgd, fs);
1182                 if (has_gdt_chksum)
1183                         bgd->bg_itable_unused = bgd->free_inodes;
1184                 ext4fs_sb_free_inodes_dec(fs->sb);
1185                 goto success;
1186         }
1187
1188 success:
1189         free(journal_buffer);
1190         free(zero_buffer);
1191
1192         return fs->curr_inode_no;
1193 fail:
1194         free(journal_buffer);
1195         free(zero_buffer);
1196
1197         return -1;
1198
1199 }
1200
1201
1202 static void alloc_single_indirect_block(struct ext2_inode *file_inode,
1203                                         unsigned int *total_remaining_blocks,
1204                                         unsigned int *no_blks_reqd)
1205 {
1206         short i;
1207         short status;
1208         long int actual_block_no;
1209         long int si_blockno;
1210         /* si :single indirect */
1211         __le32 *si_buffer = NULL;
1212         __le32 *si_start_addr = NULL;
1213         struct ext_filesystem *fs = get_fs();
1214
1215         if (*total_remaining_blocks != 0) {
1216                 si_buffer = zalloc(fs->blksz);
1217                 if (!si_buffer) {
1218                         printf("No Memory\n");
1219                         return;
1220                 }
1221                 si_start_addr = si_buffer;
1222                 si_blockno = ext4fs_get_new_blk_no();
1223                 if (si_blockno == -1) {
1224                         printf("no block left to assign\n");
1225                         goto fail;
1226                 }
1227                 (*no_blks_reqd)++;
1228                 debug("SIPB %ld: %u\n", si_blockno, *total_remaining_blocks);
1229
1230                 status = ext4fs_devread((lbaint_t)si_blockno * fs->sect_perblk,
1231                                         0, fs->blksz, (char *)si_buffer);
1232                 memset(si_buffer, '\0', fs->blksz);
1233                 if (status == 0)
1234                         goto fail;
1235
1236                 for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
1237                         actual_block_no = ext4fs_get_new_blk_no();
1238                         if (actual_block_no == -1) {
1239                                 printf("no block left to assign\n");
1240                                 goto fail;
1241                         }
1242                         *si_buffer = cpu_to_le32(actual_block_no);
1243                         debug("SIAB %u: %u\n", *si_buffer,
1244                                 *total_remaining_blocks);
1245
1246                         si_buffer++;
1247                         (*total_remaining_blocks)--;
1248                         if (*total_remaining_blocks == 0)
1249                                 break;
1250                 }
1251
1252                 /* write the block to disk */
1253                 put_ext4(((uint64_t) ((uint64_t)si_blockno * (uint64_t)fs->blksz)),
1254                          si_start_addr, fs->blksz);
1255                 file_inode->b.blocks.indir_block = cpu_to_le32(si_blockno);
1256         }
1257 fail:
1258         free(si_start_addr);
1259 }
1260
1261 static void alloc_double_indirect_block(struct ext2_inode *file_inode,
1262                                         unsigned int *total_remaining_blocks,
1263                                         unsigned int *no_blks_reqd)
1264 {
1265         short i;
1266         short j;
1267         short status;
1268         long int actual_block_no;
1269         /* di:double indirect */
1270         long int di_blockno_parent;
1271         long int di_blockno_child;
1272         __le32 *di_parent_buffer = NULL;
1273         __le32 *di_child_buff = NULL;
1274         __le32 *di_block_start_addr = NULL;
1275         __le32 *di_child_buff_start = NULL;
1276         struct ext_filesystem *fs = get_fs();
1277
1278         if (*total_remaining_blocks != 0) {
1279                 /* double indirect parent block connecting to inode */
1280                 di_blockno_parent = ext4fs_get_new_blk_no();
1281                 if (di_blockno_parent == -1) {
1282                         printf("no block left to assign\n");
1283                         goto fail;
1284                 }
1285                 di_parent_buffer = zalloc(fs->blksz);
1286                 if (!di_parent_buffer)
1287                         goto fail;
1288
1289                 di_block_start_addr = di_parent_buffer;
1290                 (*no_blks_reqd)++;
1291                 debug("DIPB %ld: %u\n", di_blockno_parent,
1292                       *total_remaining_blocks);
1293
1294                 status = ext4fs_devread((lbaint_t)di_blockno_parent *
1295                                         fs->sect_perblk, 0,
1296                                         fs->blksz, (char *)di_parent_buffer);
1297
1298                 if (!status) {
1299                         printf("%s: Device read error!\n", __func__);
1300                         goto fail;
1301                 }
1302                 memset(di_parent_buffer, '\0', fs->blksz);
1303
1304                 /*
1305                  * start:for each double indirect parent
1306                  * block create one more block
1307                  */
1308                 for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
1309                         di_blockno_child = ext4fs_get_new_blk_no();
1310                         if (di_blockno_child == -1) {
1311                                 printf("no block left to assign\n");
1312                                 goto fail;
1313                         }
1314                         di_child_buff = zalloc(fs->blksz);
1315                         if (!di_child_buff)
1316                                 goto fail;
1317
1318                         di_child_buff_start = di_child_buff;
1319                         *di_parent_buffer = cpu_to_le32(di_blockno_child);
1320                         di_parent_buffer++;
1321                         (*no_blks_reqd)++;
1322                         debug("DICB %ld: %u\n", di_blockno_child,
1323                               *total_remaining_blocks);
1324
1325                         status = ext4fs_devread((lbaint_t)di_blockno_child *
1326                                                 fs->sect_perblk, 0,
1327                                                 fs->blksz,
1328                                                 (char *)di_child_buff);
1329
1330                         if (!status) {
1331                                 printf("%s: Device read error!\n", __func__);
1332                                 goto fail;
1333                         }
1334                         memset(di_child_buff, '\0', fs->blksz);
1335                         /* filling of actual datablocks for each child */
1336                         for (j = 0; j < (fs->blksz / sizeof(int)); j++) {
1337                                 actual_block_no = ext4fs_get_new_blk_no();
1338                                 if (actual_block_no == -1) {
1339                                         printf("no block left to assign\n");
1340                                         goto fail;
1341                                 }
1342                                 *di_child_buff = cpu_to_le32(actual_block_no);
1343                                 debug("DIAB %ld: %u\n", actual_block_no,
1344                                       *total_remaining_blocks);
1345
1346                                 di_child_buff++;
1347                                 (*total_remaining_blocks)--;
1348                                 if (*total_remaining_blocks == 0)
1349                                         break;
1350                         }
1351                         /* write the block  table */
1352                         put_ext4(((uint64_t) ((uint64_t)di_blockno_child * (uint64_t)fs->blksz)),
1353                                  di_child_buff_start, fs->blksz);
1354                         free(di_child_buff_start);
1355                         di_child_buff_start = NULL;
1356
1357                         if (*total_remaining_blocks == 0)
1358                                 break;
1359                 }
1360                 put_ext4(((uint64_t) ((uint64_t)di_blockno_parent * (uint64_t)fs->blksz)),
1361                          di_block_start_addr, fs->blksz);
1362                 file_inode->b.blocks.double_indir_block = cpu_to_le32(di_blockno_parent);
1363         }
1364 fail:
1365         free(di_block_start_addr);
1366 }
1367
1368 static void alloc_triple_indirect_block(struct ext2_inode *file_inode,
1369                                         unsigned int *total_remaining_blocks,
1370                                         unsigned int *no_blks_reqd)
1371 {
1372         short i;
1373         short j;
1374         short k;
1375         long int actual_block_no;
1376         /* ti: Triple Indirect */
1377         long int ti_gp_blockno;
1378         long int ti_parent_blockno;
1379         long int ti_child_blockno;
1380         __le32 *ti_gp_buff = NULL;
1381         __le32 *ti_parent_buff = NULL;
1382         __le32 *ti_child_buff = NULL;
1383         __le32 *ti_gp_buff_start_addr = NULL;
1384         __le32 *ti_pbuff_start_addr = NULL;
1385         __le32 *ti_cbuff_start_addr = NULL;
1386         struct ext_filesystem *fs = get_fs();
1387         if (*total_remaining_blocks != 0) {
1388                 /* triple indirect grand parent block connecting to inode */
1389                 ti_gp_blockno = ext4fs_get_new_blk_no();
1390                 if (ti_gp_blockno == -1) {
1391                         printf("no block left to assign\n");
1392                         return;
1393                 }
1394                 ti_gp_buff = zalloc(fs->blksz);
1395                 if (!ti_gp_buff)
1396                         return;
1397
1398                 ti_gp_buff_start_addr = ti_gp_buff;
1399                 (*no_blks_reqd)++;
1400                 debug("TIGPB %ld: %u\n", ti_gp_blockno,
1401                       *total_remaining_blocks);
1402
1403                 /* for each 4 byte grand parent entry create one more block */
1404                 for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
1405                         ti_parent_blockno = ext4fs_get_new_blk_no();
1406                         if (ti_parent_blockno == -1) {
1407                                 printf("no block left to assign\n");
1408                                 goto fail;
1409                         }
1410                         ti_parent_buff = zalloc(fs->blksz);
1411                         if (!ti_parent_buff)
1412                                 goto fail;
1413
1414                         ti_pbuff_start_addr = ti_parent_buff;
1415                         *ti_gp_buff = cpu_to_le32(ti_parent_blockno);
1416                         ti_gp_buff++;
1417                         (*no_blks_reqd)++;
1418                         debug("TIPB %ld: %u\n", ti_parent_blockno,
1419                               *total_remaining_blocks);
1420
1421                         /* for each 4 byte entry parent create one more block */
1422                         for (j = 0; j < (fs->blksz / sizeof(int)); j++) {
1423                                 ti_child_blockno = ext4fs_get_new_blk_no();
1424                                 if (ti_child_blockno == -1) {
1425                                         printf("no block left assign\n");
1426                                         goto fail1;
1427                                 }
1428                                 ti_child_buff = zalloc(fs->blksz);
1429                                 if (!ti_child_buff)
1430                                         goto fail1;
1431
1432                                 ti_cbuff_start_addr = ti_child_buff;
1433                                 *ti_parent_buff = cpu_to_le32(ti_child_blockno);
1434                                 ti_parent_buff++;
1435                                 (*no_blks_reqd)++;
1436                                 debug("TICB %ld: %u\n", ti_parent_blockno,
1437                                       *total_remaining_blocks);
1438
1439                                 /* fill actual datablocks for each child */
1440                                 for (k = 0; k < (fs->blksz / sizeof(int));
1441                                         k++) {
1442                                         actual_block_no =
1443                                             ext4fs_get_new_blk_no();
1444                                         if (actual_block_no == -1) {
1445                                                 printf("no block left\n");
1446                                                 free(ti_cbuff_start_addr);
1447                                                 goto fail1;
1448                                         }
1449                                         *ti_child_buff = cpu_to_le32(actual_block_no);
1450                                         debug("TIAB %ld: %u\n", actual_block_no,
1451                                               *total_remaining_blocks);
1452
1453                                         ti_child_buff++;
1454                                         (*total_remaining_blocks)--;
1455                                         if (*total_remaining_blocks == 0)
1456                                                 break;
1457                                 }
1458                                 /* write the child block */
1459                                 put_ext4(((uint64_t) ((uint64_t)ti_child_blockno *
1460                                                       (uint64_t)fs->blksz)),
1461                                          ti_cbuff_start_addr, fs->blksz);
1462                                 free(ti_cbuff_start_addr);
1463
1464                                 if (*total_remaining_blocks == 0)
1465                                         break;
1466                         }
1467                         /* write the parent block */
1468                         put_ext4(((uint64_t) ((uint64_t)ti_parent_blockno * (uint64_t)fs->blksz)),
1469                                  ti_pbuff_start_addr, fs->blksz);
1470                         free(ti_pbuff_start_addr);
1471
1472                         if (*total_remaining_blocks == 0)
1473                                 break;
1474                 }
1475                 /* write the grand parent block */
1476                 put_ext4(((uint64_t) ((uint64_t)ti_gp_blockno * (uint64_t)fs->blksz)),
1477                          ti_gp_buff_start_addr, fs->blksz);
1478                 file_inode->b.blocks.triple_indir_block = cpu_to_le32(ti_gp_blockno);
1479                 free(ti_gp_buff_start_addr);
1480                 return;
1481         }
1482 fail1:
1483         free(ti_pbuff_start_addr);
1484 fail:
1485         free(ti_gp_buff_start_addr);
1486 }
1487
1488 void ext4fs_allocate_blocks(struct ext2_inode *file_inode,
1489                                 unsigned int total_remaining_blocks,
1490                                 unsigned int *total_no_of_block)
1491 {
1492         short i;
1493         long int direct_blockno;
1494         unsigned int no_blks_reqd = 0;
1495
1496         /* allocation of direct blocks */
1497         for (i = 0; total_remaining_blocks && i < INDIRECT_BLOCKS; i++) {
1498                 direct_blockno = ext4fs_get_new_blk_no();
1499                 if (direct_blockno == -1) {
1500                         printf("no block left to assign\n");
1501                         return;
1502                 }
1503                 file_inode->b.blocks.dir_blocks[i] = cpu_to_le32(direct_blockno);
1504                 debug("DB %ld: %u\n", direct_blockno, total_remaining_blocks);
1505
1506                 total_remaining_blocks--;
1507         }
1508
1509         alloc_single_indirect_block(file_inode, &total_remaining_blocks,
1510                                     &no_blks_reqd);
1511         alloc_double_indirect_block(file_inode, &total_remaining_blocks,
1512                                     &no_blks_reqd);
1513         alloc_triple_indirect_block(file_inode, &total_remaining_blocks,
1514                                     &no_blks_reqd);
1515         *total_no_of_block += no_blks_reqd;
1516 }
1517
1518 #endif
1519
1520 static struct ext4_extent_header *ext4fs_get_extent_block
1521         (struct ext2_data *data, char *buf,
1522                 struct ext4_extent_header *ext_block,
1523                 uint32_t fileblock, int log2_blksz)
1524 {
1525         struct ext4_extent_idx *index;
1526         unsigned long long block;
1527         int blksz = EXT2_BLOCK_SIZE(data);
1528         int i;
1529
1530         while (1) {
1531                 index = (struct ext4_extent_idx *)(ext_block + 1);
1532
1533                 if (le16_to_cpu(ext_block->eh_magic) != EXT4_EXT_MAGIC)
1534                         return NULL;
1535
1536                 if (ext_block->eh_depth == 0)
1537                         return ext_block;
1538                 i = -1;
1539                 do {
1540                         i++;
1541                         if (i >= le16_to_cpu(ext_block->eh_entries))
1542                                 break;
1543                 } while (fileblock >= le32_to_cpu(index[i].ei_block));
1544
1545                 if (--i < 0)
1546                         return NULL;
1547
1548                 block = le16_to_cpu(index[i].ei_leaf_hi);
1549                 block = (block << 32) + le32_to_cpu(index[i].ei_leaf_lo);
1550
1551                 if (ext4fs_devread((lbaint_t)block << log2_blksz, 0, blksz,
1552                                    buf))
1553                         ext_block = (struct ext4_extent_header *)buf;
1554                 else
1555                         return NULL;
1556         }
1557 }
1558
1559 static int ext4fs_blockgroup
1560         (struct ext2_data *data, int group, struct ext2_block_group *blkgrp)
1561 {
1562         long int blkno;
1563         unsigned int blkoff, desc_per_blk;
1564         int log2blksz = get_fs()->dev_desc->log2blksz;
1565         int desc_size = get_fs()->gdsize;
1566
1567         desc_per_blk = EXT2_BLOCK_SIZE(data) / desc_size;
1568
1569         blkno = le32_to_cpu(data->sblock.first_data_block) + 1 +
1570                         group / desc_per_blk;
1571         blkoff = (group % desc_per_blk) * desc_size;
1572
1573         debug("ext4fs read %d group descriptor (blkno %ld blkoff %u)\n",
1574               group, blkno, blkoff);
1575
1576         return ext4fs_devread((lbaint_t)blkno <<
1577                               (LOG2_BLOCK_SIZE(data) - log2blksz),
1578                               blkoff, desc_size, (char *)blkgrp);
1579 }
1580
1581 int ext4fs_read_inode(struct ext2_data *data, int ino, struct ext2_inode *inode)
1582 {
1583         struct ext2_block_group blkgrp;
1584         struct ext2_sblock *sblock = &data->sblock;
1585         struct ext_filesystem *fs = get_fs();
1586         int log2blksz = get_fs()->dev_desc->log2blksz;
1587         int inodes_per_block, status;
1588         long int blkno;
1589         unsigned int blkoff;
1590
1591         /* It is easier to calculate if the first inode is 0. */
1592         ino--;
1593         status = ext4fs_blockgroup(data, ino / le32_to_cpu
1594                                    (sblock->inodes_per_group), &blkgrp);
1595         if (status == 0)
1596                 return 0;
1597
1598         inodes_per_block = EXT2_BLOCK_SIZE(data) / fs->inodesz;
1599         blkno = ext4fs_bg_get_inode_table_id(&blkgrp, fs) +
1600             (ino % le32_to_cpu(sblock->inodes_per_group)) / inodes_per_block;
1601         blkoff = (ino % inodes_per_block) * fs->inodesz;
1602         /* Read the inode. */
1603         status = ext4fs_devread((lbaint_t)blkno << (LOG2_BLOCK_SIZE(data) -
1604                                 log2blksz), blkoff,
1605                                 sizeof(struct ext2_inode), (char *)inode);
1606         if (status == 0)
1607                 return 0;
1608
1609         return 1;
1610 }
1611
1612 long int read_allocated_block(struct ext2_inode *inode, int fileblock)
1613 {
1614         long int blknr;
1615         int blksz;
1616         int log2_blksz;
1617         int status;
1618         long int rblock;
1619         long int perblock_parent;
1620         long int perblock_child;
1621         unsigned long long start;
1622         /* get the blocksize of the filesystem */
1623         blksz = EXT2_BLOCK_SIZE(ext4fs_root);
1624         log2_blksz = LOG2_BLOCK_SIZE(ext4fs_root)
1625                 - get_fs()->dev_desc->log2blksz;
1626
1627         if (le32_to_cpu(inode->flags) & EXT4_EXTENTS_FL) {
1628                 char *buf = zalloc(blksz);
1629                 if (!buf)
1630                         return -ENOMEM;
1631                 struct ext4_extent_header *ext_block;
1632                 struct ext4_extent *extent;
1633                 int i = -1;
1634                 ext_block =
1635                         ext4fs_get_extent_block(ext4fs_root, buf,
1636                                                 (struct ext4_extent_header *)
1637                                                 inode->b.blocks.dir_blocks,
1638                                                 fileblock, log2_blksz);
1639                 if (!ext_block) {
1640                         printf("invalid extent block\n");
1641                         free(buf);
1642                         return -EINVAL;
1643                 }
1644
1645                 extent = (struct ext4_extent *)(ext_block + 1);
1646
1647                 do {
1648                         i++;
1649                         if (i >= le16_to_cpu(ext_block->eh_entries))
1650                                 break;
1651                 } while (fileblock >= le32_to_cpu(extent[i].ee_block));
1652                 if (--i >= 0) {
1653                         fileblock -= le32_to_cpu(extent[i].ee_block);
1654                         if (fileblock >= le16_to_cpu(extent[i].ee_len)) {
1655                                 free(buf);
1656                                 return 0;
1657                         }
1658
1659                         start = le16_to_cpu(extent[i].ee_start_hi);
1660                         start = (start << 32) +
1661                                         le32_to_cpu(extent[i].ee_start_lo);
1662                         free(buf);
1663                         return fileblock + start;
1664                 }
1665
1666                 printf("Extent Error\n");
1667                 free(buf);
1668                 return -1;
1669         }
1670
1671         /* Direct blocks. */
1672         if (fileblock < INDIRECT_BLOCKS)
1673                 blknr = le32_to_cpu(inode->b.blocks.dir_blocks[fileblock]);
1674
1675         /* Indirect. */
1676         else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4))) {
1677                 if (ext4fs_indir1_block == NULL) {
1678                         ext4fs_indir1_block = zalloc(blksz);
1679                         if (ext4fs_indir1_block == NULL) {
1680                                 printf("** SI ext2fs read block (indir 1)"
1681                                         "malloc failed. **\n");
1682                                 return -1;
1683                         }
1684                         ext4fs_indir1_size = blksz;
1685                         ext4fs_indir1_blkno = -1;
1686                 }
1687                 if (blksz != ext4fs_indir1_size) {
1688                         free(ext4fs_indir1_block);
1689                         ext4fs_indir1_block = NULL;
1690                         ext4fs_indir1_size = 0;
1691                         ext4fs_indir1_blkno = -1;
1692                         ext4fs_indir1_block = zalloc(blksz);
1693                         if (ext4fs_indir1_block == NULL) {
1694                                 printf("** SI ext2fs read block (indir 1):"
1695                                         "malloc failed. **\n");
1696                                 return -1;
1697                         }
1698                         ext4fs_indir1_size = blksz;
1699                 }
1700                 if ((le32_to_cpu(inode->b.blocks.indir_block) <<
1701                      log2_blksz) != ext4fs_indir1_blkno) {
1702                         status =
1703                             ext4fs_devread((lbaint_t)le32_to_cpu
1704                                            (inode->b.blocks.
1705                                             indir_block) << log2_blksz, 0,
1706                                            blksz, (char *)ext4fs_indir1_block);
1707                         if (status == 0) {
1708                                 printf("** SI ext2fs read block (indir 1)"
1709                                         "failed. **\n");
1710                                 return -1;
1711                         }
1712                         ext4fs_indir1_blkno =
1713                                 le32_to_cpu(inode->b.blocks.
1714                                                indir_block) << log2_blksz;
1715                 }
1716                 blknr = le32_to_cpu(ext4fs_indir1_block
1717                                       [fileblock - INDIRECT_BLOCKS]);
1718         }
1719         /* Double indirect. */
1720         else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4 *
1721                                         (blksz / 4 + 1)))) {
1722
1723                 long int perblock = blksz / 4;
1724                 long int rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4);
1725
1726                 if (ext4fs_indir1_block == NULL) {
1727                         ext4fs_indir1_block = zalloc(blksz);
1728                         if (ext4fs_indir1_block == NULL) {
1729                                 printf("** DI ext2fs read block (indir 2 1)"
1730                                         "malloc failed. **\n");
1731                                 return -1;
1732                         }
1733                         ext4fs_indir1_size = blksz;
1734                         ext4fs_indir1_blkno = -1;
1735                 }
1736                 if (blksz != ext4fs_indir1_size) {
1737                         free(ext4fs_indir1_block);
1738                         ext4fs_indir1_block = NULL;
1739                         ext4fs_indir1_size = 0;
1740                         ext4fs_indir1_blkno = -1;
1741                         ext4fs_indir1_block = zalloc(blksz);
1742                         if (ext4fs_indir1_block == NULL) {
1743                                 printf("** DI ext2fs read block (indir 2 1)"
1744                                         "malloc failed. **\n");
1745                                 return -1;
1746                         }
1747                         ext4fs_indir1_size = blksz;
1748                 }
1749                 if ((le32_to_cpu(inode->b.blocks.double_indir_block) <<
1750                      log2_blksz) != ext4fs_indir1_blkno) {
1751                         status =
1752                             ext4fs_devread((lbaint_t)le32_to_cpu
1753                                            (inode->b.blocks.
1754                                             double_indir_block) << log2_blksz,
1755                                            0, blksz,
1756                                            (char *)ext4fs_indir1_block);
1757                         if (status == 0) {
1758                                 printf("** DI ext2fs read block (indir 2 1)"
1759                                         "failed. **\n");
1760                                 return -1;
1761                         }
1762                         ext4fs_indir1_blkno =
1763                             le32_to_cpu(inode->b.blocks.double_indir_block) <<
1764                             log2_blksz;
1765                 }
1766
1767                 if (ext4fs_indir2_block == NULL) {
1768                         ext4fs_indir2_block = zalloc(blksz);
1769                         if (ext4fs_indir2_block == NULL) {
1770                                 printf("** DI ext2fs read block (indir 2 2)"
1771                                         "malloc failed. **\n");
1772                                 return -1;
1773                         }
1774                         ext4fs_indir2_size = blksz;
1775                         ext4fs_indir2_blkno = -1;
1776                 }
1777                 if (blksz != ext4fs_indir2_size) {
1778                         free(ext4fs_indir2_block);
1779                         ext4fs_indir2_block = NULL;
1780                         ext4fs_indir2_size = 0;
1781                         ext4fs_indir2_blkno = -1;
1782                         ext4fs_indir2_block = zalloc(blksz);
1783                         if (ext4fs_indir2_block == NULL) {
1784                                 printf("** DI ext2fs read block (indir 2 2)"
1785                                         "malloc failed. **\n");
1786                                 return -1;
1787                         }
1788                         ext4fs_indir2_size = blksz;
1789                 }
1790                 if ((le32_to_cpu(ext4fs_indir1_block[rblock / perblock]) <<
1791                      log2_blksz) != ext4fs_indir2_blkno) {
1792                         status = ext4fs_devread((lbaint_t)le32_to_cpu
1793                                                 (ext4fs_indir1_block
1794                                                  [rblock /
1795                                                   perblock]) << log2_blksz, 0,
1796                                                 blksz,
1797                                                 (char *)ext4fs_indir2_block);
1798                         if (status == 0) {
1799                                 printf("** DI 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                                                               /
1806                                                               perblock]) <<
1807                             log2_blksz;
1808                 }
1809                 blknr = le32_to_cpu(ext4fs_indir2_block[rblock % perblock]);
1810         }
1811         /* Tripple indirect. */
1812         else {
1813                 rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4 +
1814                                       (blksz / 4 * blksz / 4));
1815                 perblock_child = blksz / 4;
1816                 perblock_parent = ((blksz / 4) * (blksz / 4));
1817
1818                 if (ext4fs_indir1_block == NULL) {
1819                         ext4fs_indir1_block = zalloc(blksz);
1820                         if (ext4fs_indir1_block == NULL) {
1821                                 printf("** TI ext2fs read block (indir 2 1)"
1822                                         "malloc failed. **\n");
1823                                 return -1;
1824                         }
1825                         ext4fs_indir1_size = blksz;
1826                         ext4fs_indir1_blkno = -1;
1827                 }
1828                 if (blksz != ext4fs_indir1_size) {
1829                         free(ext4fs_indir1_block);
1830                         ext4fs_indir1_block = NULL;
1831                         ext4fs_indir1_size = 0;
1832                         ext4fs_indir1_blkno = -1;
1833                         ext4fs_indir1_block = zalloc(blksz);
1834                         if (ext4fs_indir1_block == NULL) {
1835                                 printf("** TI ext2fs read block (indir 2 1)"
1836                                         "malloc failed. **\n");
1837                                 return -1;
1838                         }
1839                         ext4fs_indir1_size = blksz;
1840                 }
1841                 if ((le32_to_cpu(inode->b.blocks.triple_indir_block) <<
1842                      log2_blksz) != ext4fs_indir1_blkno) {
1843                         status = ext4fs_devread
1844                             ((lbaint_t)
1845                              le32_to_cpu(inode->b.blocks.triple_indir_block)
1846                              << log2_blksz, 0, blksz,
1847                              (char *)ext4fs_indir1_block);
1848                         if (status == 0) {
1849                                 printf("** TI ext2fs read block (indir 2 1)"
1850                                         "failed. **\n");
1851                                 return -1;
1852                         }
1853                         ext4fs_indir1_blkno =
1854                             le32_to_cpu(inode->b.blocks.triple_indir_block) <<
1855                             log2_blksz;
1856                 }
1857
1858                 if (ext4fs_indir2_block == NULL) {
1859                         ext4fs_indir2_block = zalloc(blksz);
1860                         if (ext4fs_indir2_block == NULL) {
1861                                 printf("** TI ext2fs read block (indir 2 2)"
1862                                         "malloc failed. **\n");
1863                                 return -1;
1864                         }
1865                         ext4fs_indir2_size = blksz;
1866                         ext4fs_indir2_blkno = -1;
1867                 }
1868                 if (blksz != ext4fs_indir2_size) {
1869                         free(ext4fs_indir2_block);
1870                         ext4fs_indir2_block = NULL;
1871                         ext4fs_indir2_size = 0;
1872                         ext4fs_indir2_blkno = -1;
1873                         ext4fs_indir2_block = zalloc(blksz);
1874                         if (ext4fs_indir2_block == NULL) {
1875                                 printf("** TI ext2fs read block (indir 2 2)"
1876                                         "malloc failed. **\n");
1877                                 return -1;
1878                         }
1879                         ext4fs_indir2_size = blksz;
1880                 }
1881                 if ((le32_to_cpu(ext4fs_indir1_block[rblock /
1882                                                        perblock_parent]) <<
1883                      log2_blksz)
1884                     != ext4fs_indir2_blkno) {
1885                         status = ext4fs_devread((lbaint_t)le32_to_cpu
1886                                                 (ext4fs_indir1_block
1887                                                  [rblock /
1888                                                   perblock_parent]) <<
1889                                                 log2_blksz, 0, blksz,
1890                                                 (char *)ext4fs_indir2_block);
1891                         if (status == 0) {
1892                                 printf("** TI ext2fs read block (indir 2 2)"
1893                                         "failed. **\n");
1894                                 return -1;
1895                         }
1896                         ext4fs_indir2_blkno =
1897                             le32_to_cpu(ext4fs_indir1_block[rblock /
1898                                                               perblock_parent])
1899                             << log2_blksz;
1900                 }
1901
1902                 if (ext4fs_indir3_block == NULL) {
1903                         ext4fs_indir3_block = zalloc(blksz);
1904                         if (ext4fs_indir3_block == NULL) {
1905                                 printf("** TI ext2fs read block (indir 2 2)"
1906                                         "malloc failed. **\n");
1907                                 return -1;
1908                         }
1909                         ext4fs_indir3_size = blksz;
1910                         ext4fs_indir3_blkno = -1;
1911                 }
1912                 if (blksz != ext4fs_indir3_size) {
1913                         free(ext4fs_indir3_block);
1914                         ext4fs_indir3_block = NULL;
1915                         ext4fs_indir3_size = 0;
1916                         ext4fs_indir3_blkno = -1;
1917                         ext4fs_indir3_block = zalloc(blksz);
1918                         if (ext4fs_indir3_block == NULL) {
1919                                 printf("** TI ext2fs read block (indir 2 2)"
1920                                         "malloc failed. **\n");
1921                                 return -1;
1922                         }
1923                         ext4fs_indir3_size = blksz;
1924                 }
1925                 if ((le32_to_cpu(ext4fs_indir2_block[rblock
1926                                                        /
1927                                                        perblock_child]) <<
1928                      log2_blksz) != ext4fs_indir3_blkno) {
1929                         status =
1930                             ext4fs_devread((lbaint_t)le32_to_cpu
1931                                            (ext4fs_indir2_block
1932                                             [(rblock / perblock_child)
1933                                              % (blksz / 4)]) << log2_blksz, 0,
1934                                            blksz, (char *)ext4fs_indir3_block);
1935                         if (status == 0) {
1936                                 printf("** TI ext2fs read block (indir 2 2)"
1937                                        "failed. **\n");
1938                                 return -1;
1939                         }
1940                         ext4fs_indir3_blkno =
1941                             le32_to_cpu(ext4fs_indir2_block[(rblock /
1942                                                                perblock_child) %
1943                                                               (blksz /
1944                                                                4)]) <<
1945                             log2_blksz;
1946                 }
1947
1948                 blknr = le32_to_cpu(ext4fs_indir3_block
1949                                       [rblock % perblock_child]);
1950         }
1951         debug("read_allocated_block %ld\n", blknr);
1952
1953         return blknr;
1954 }
1955
1956 /**
1957  * ext4fs_reinit_global() - Reinitialize values of ext4 write implementation's
1958  *                          global pointers
1959  *
1960  * This function assures that for a file with the same name but different size
1961  * the sequential store on the ext4 filesystem will be correct.
1962  *
1963  * In this function the global data, responsible for internal representation
1964  * of the ext4 data are initialized to the reset state. Without this, during
1965  * replacement of the smaller file with the bigger truncation of new file was
1966  * performed.
1967  */
1968 void ext4fs_reinit_global(void)
1969 {
1970         if (ext4fs_indir1_block != NULL) {
1971                 free(ext4fs_indir1_block);
1972                 ext4fs_indir1_block = NULL;
1973                 ext4fs_indir1_size = 0;
1974                 ext4fs_indir1_blkno = -1;
1975         }
1976         if (ext4fs_indir2_block != NULL) {
1977                 free(ext4fs_indir2_block);
1978                 ext4fs_indir2_block = NULL;
1979                 ext4fs_indir2_size = 0;
1980                 ext4fs_indir2_blkno = -1;
1981         }
1982         if (ext4fs_indir3_block != NULL) {
1983                 free(ext4fs_indir3_block);
1984                 ext4fs_indir3_block = NULL;
1985                 ext4fs_indir3_size = 0;
1986                 ext4fs_indir3_blkno = -1;
1987         }
1988 }
1989 void ext4fs_close(void)
1990 {
1991         if ((ext4fs_file != NULL) && (ext4fs_root != NULL)) {
1992                 ext4fs_free_node(ext4fs_file, &ext4fs_root->diropen);
1993                 ext4fs_file = NULL;
1994         }
1995         if (ext4fs_root != NULL) {
1996                 free(ext4fs_root);
1997                 ext4fs_root = NULL;
1998         }
1999
2000         ext4fs_reinit_global();
2001 }
2002
2003 int ext4fs_iterate_dir(struct ext2fs_node *dir, char *name,
2004                                 struct ext2fs_node **fnode, int *ftype)
2005 {
2006         unsigned int fpos = 0;
2007         int status;
2008         loff_t actread;
2009         struct ext2fs_node *diro = (struct ext2fs_node *) dir;
2010
2011 #ifdef DEBUG
2012         if (name != NULL)
2013                 printf("Iterate dir %s\n", name);
2014 #endif /* of DEBUG */
2015         if (!diro->inode_read) {
2016                 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode);
2017                 if (status == 0)
2018                         return 0;
2019         }
2020         /* Search the file.  */
2021         while (fpos < le32_to_cpu(diro->inode.size)) {
2022                 struct ext2_dirent dirent;
2023
2024                 status = ext4fs_read_file(diro, fpos,
2025                                            sizeof(struct ext2_dirent),
2026                                            (char *)&dirent, &actread);
2027                 if (status < 0)
2028                         return 0;
2029
2030                 if (dirent.direntlen == 0) {
2031                         printf("Failed to iterate over directory %s\n", name);
2032                         return 0;
2033                 }
2034
2035                 if (dirent.namelen != 0) {
2036                         char filename[dirent.namelen + 1];
2037                         struct ext2fs_node *fdiro;
2038                         int type = FILETYPE_UNKNOWN;
2039
2040                         status = ext4fs_read_file(diro,
2041                                                   fpos +
2042                                                   sizeof(struct ext2_dirent),
2043                                                   dirent.namelen, filename,
2044                                                   &actread);
2045                         if (status < 0)
2046                                 return 0;
2047
2048                         fdiro = zalloc(sizeof(struct ext2fs_node));
2049                         if (!fdiro)
2050                                 return 0;
2051
2052                         fdiro->data = diro->data;
2053                         fdiro->ino = le32_to_cpu(dirent.inode);
2054
2055                         filename[dirent.namelen] = '\0';
2056
2057                         if (dirent.filetype != FILETYPE_UNKNOWN) {
2058                                 fdiro->inode_read = 0;
2059
2060                                 if (dirent.filetype == FILETYPE_DIRECTORY)
2061                                         type = FILETYPE_DIRECTORY;
2062                                 else if (dirent.filetype == FILETYPE_SYMLINK)
2063                                         type = FILETYPE_SYMLINK;
2064                                 else if (dirent.filetype == FILETYPE_REG)
2065                                         type = FILETYPE_REG;
2066                         } else {
2067                                 status = ext4fs_read_inode(diro->data,
2068                                                            le32_to_cpu
2069                                                            (dirent.inode),
2070                                                            &fdiro->inode);
2071                                 if (status == 0) {
2072                                         free(fdiro);
2073                                         return 0;
2074                                 }
2075                                 fdiro->inode_read = 1;
2076
2077                                 if ((le16_to_cpu(fdiro->inode.mode) &
2078                                      FILETYPE_INO_MASK) ==
2079                                     FILETYPE_INO_DIRECTORY) {
2080                                         type = FILETYPE_DIRECTORY;
2081                                 } else if ((le16_to_cpu(fdiro->inode.mode)
2082                                             & FILETYPE_INO_MASK) ==
2083                                            FILETYPE_INO_SYMLINK) {
2084                                         type = FILETYPE_SYMLINK;
2085                                 } else if ((le16_to_cpu(fdiro->inode.mode)
2086                                             & FILETYPE_INO_MASK) ==
2087                                            FILETYPE_INO_REG) {
2088                                         type = FILETYPE_REG;
2089                                 }
2090                         }
2091 #ifdef DEBUG
2092                         printf("iterate >%s<\n", filename);
2093 #endif /* of DEBUG */
2094                         if ((name != NULL) && (fnode != NULL)
2095                             && (ftype != NULL)) {
2096                                 if (strcmp(filename, name) == 0) {
2097                                         *ftype = type;
2098                                         *fnode = fdiro;
2099                                         return 1;
2100                                 }
2101                         } else {
2102                                 if (fdiro->inode_read == 0) {
2103                                         status = ext4fs_read_inode(diro->data,
2104                                                                  le32_to_cpu(
2105                                                                  dirent.inode),
2106                                                                  &fdiro->inode);
2107                                         if (status == 0) {
2108                                                 free(fdiro);
2109                                                 return 0;
2110                                         }
2111                                         fdiro->inode_read = 1;
2112                                 }
2113                                 switch (type) {
2114                                 case FILETYPE_DIRECTORY:
2115                                         printf("<DIR> ");
2116                                         break;
2117                                 case FILETYPE_SYMLINK:
2118                                         printf("<SYM> ");
2119                                         break;
2120                                 case FILETYPE_REG:
2121                                         printf("      ");
2122                                         break;
2123                                 default:
2124                                         printf("< ? > ");
2125                                         break;
2126                                 }
2127                                 printf("%10u %s\n",
2128                                        le32_to_cpu(fdiro->inode.size),
2129                                         filename);
2130                         }
2131                         free(fdiro);
2132                 }
2133                 fpos += le16_to_cpu(dirent.direntlen);
2134         }
2135         return 0;
2136 }
2137
2138 static char *ext4fs_read_symlink(struct ext2fs_node *node)
2139 {
2140         char *symlink;
2141         struct ext2fs_node *diro = node;
2142         int status;
2143         loff_t actread;
2144
2145         if (!diro->inode_read) {
2146                 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode);
2147                 if (status == 0)
2148                         return NULL;
2149         }
2150         symlink = zalloc(le32_to_cpu(diro->inode.size) + 1);
2151         if (!symlink)
2152                 return NULL;
2153
2154         if (le32_to_cpu(diro->inode.size) < sizeof(diro->inode.b.symlink)) {
2155                 strncpy(symlink, diro->inode.b.symlink,
2156                          le32_to_cpu(diro->inode.size));
2157         } else {
2158                 status = ext4fs_read_file(diro, 0,
2159                                            le32_to_cpu(diro->inode.size),
2160                                            symlink, &actread);
2161                 if ((status < 0) || (actread == 0)) {
2162                         free(symlink);
2163                         return NULL;
2164                 }
2165         }
2166         symlink[le32_to_cpu(diro->inode.size)] = '\0';
2167         return symlink;
2168 }
2169
2170 static int ext4fs_find_file1(const char *currpath,
2171                              struct ext2fs_node *currroot,
2172                              struct ext2fs_node **currfound, int *foundtype)
2173 {
2174         char fpath[strlen(currpath) + 1];
2175         char *name = fpath;
2176         char *next;
2177         int status;
2178         int type = FILETYPE_DIRECTORY;
2179         struct ext2fs_node *currnode = currroot;
2180         struct ext2fs_node *oldnode = currroot;
2181
2182         strncpy(fpath, currpath, strlen(currpath) + 1);
2183
2184         /* Remove all leading slashes. */
2185         while (*name == '/')
2186                 name++;
2187
2188         if (!*name) {
2189                 *currfound = currnode;
2190                 return 1;
2191         }
2192
2193         for (;;) {
2194                 int found;
2195
2196                 /* Extract the actual part from the pathname. */
2197                 next = strchr(name, '/');
2198                 if (next) {
2199                         /* Remove all leading slashes. */
2200                         while (*next == '/')
2201                                 *(next++) = '\0';
2202                 }
2203
2204                 if (type != FILETYPE_DIRECTORY) {
2205                         ext4fs_free_node(currnode, currroot);
2206                         return 0;
2207                 }
2208
2209                 oldnode = currnode;
2210
2211                 /* Iterate over the directory. */
2212                 found = ext4fs_iterate_dir(currnode, name, &currnode, &type);
2213                 if (found == 0)
2214                         return 0;
2215
2216                 if (found == -1)
2217                         break;
2218
2219                 /* Read in the symlink and follow it. */
2220                 if (type == FILETYPE_SYMLINK) {
2221                         char *symlink;
2222
2223                         /* Test if the symlink does not loop. */
2224                         if (++symlinknest == 8) {
2225                                 ext4fs_free_node(currnode, currroot);
2226                                 ext4fs_free_node(oldnode, currroot);
2227                                 return 0;
2228                         }
2229
2230                         symlink = ext4fs_read_symlink(currnode);
2231                         ext4fs_free_node(currnode, currroot);
2232
2233                         if (!symlink) {
2234                                 ext4fs_free_node(oldnode, currroot);
2235                                 return 0;
2236                         }
2237
2238                         debug("Got symlink >%s<\n", symlink);
2239
2240                         if (symlink[0] == '/') {
2241                                 ext4fs_free_node(oldnode, currroot);
2242                                 oldnode = &ext4fs_root->diropen;
2243                         }
2244
2245                         /* Lookup the node the symlink points to. */
2246                         status = ext4fs_find_file1(symlink, oldnode,
2247                                                     &currnode, &type);
2248
2249                         free(symlink);
2250
2251                         if (status == 0) {
2252                                 ext4fs_free_node(oldnode, currroot);
2253                                 return 0;
2254                         }
2255                 }
2256
2257                 ext4fs_free_node(oldnode, currroot);
2258
2259                 /* Found the node! */
2260                 if (!next || *next == '\0') {
2261                         *currfound = currnode;
2262                         *foundtype = type;
2263                         return 1;
2264                 }
2265                 name = next;
2266         }
2267         return -1;
2268 }
2269
2270 int ext4fs_find_file(const char *path, struct ext2fs_node *rootnode,
2271         struct ext2fs_node **foundnode, int expecttype)
2272 {
2273         int status;
2274         int foundtype = FILETYPE_DIRECTORY;
2275
2276         symlinknest = 0;
2277         if (!path)
2278                 return 0;
2279
2280         status = ext4fs_find_file1(path, rootnode, foundnode, &foundtype);
2281         if (status == 0)
2282                 return 0;
2283
2284         /* Check if the node that was found was of the expected type. */
2285         if ((expecttype == FILETYPE_REG) && (foundtype != expecttype))
2286                 return 0;
2287         else if ((expecttype == FILETYPE_DIRECTORY)
2288                    && (foundtype != expecttype))
2289                 return 0;
2290
2291         return 1;
2292 }
2293
2294 int ext4fs_open(const char *filename, loff_t *len)
2295 {
2296         struct ext2fs_node *fdiro = NULL;
2297         int status;
2298
2299         if (ext4fs_root == NULL)
2300                 return -1;
2301
2302         ext4fs_file = NULL;
2303         status = ext4fs_find_file(filename, &ext4fs_root->diropen, &fdiro,
2304                                   FILETYPE_REG);
2305         if (status == 0)
2306                 goto fail;
2307
2308         if (!fdiro->inode_read) {
2309                 status = ext4fs_read_inode(fdiro->data, fdiro->ino,
2310                                 &fdiro->inode);
2311                 if (status == 0)
2312                         goto fail;
2313         }
2314         *len = le32_to_cpu(fdiro->inode.size);
2315         ext4fs_file = fdiro;
2316
2317         return 0;
2318 fail:
2319         ext4fs_free_node(fdiro, &ext4fs_root->diropen);
2320
2321         return -1;
2322 }
2323
2324 int ext4fs_mount(unsigned part_length)
2325 {
2326         struct ext2_data *data;
2327         int status;
2328         struct ext_filesystem *fs = get_fs();
2329         data = zalloc(SUPERBLOCK_SIZE);
2330         if (!data)
2331                 return 0;
2332
2333         /* Read the superblock. */
2334         status = ext4_read_superblock((char *)&data->sblock);
2335
2336         if (status == 0)
2337                 goto fail;
2338
2339         /* Make sure this is an ext2 filesystem. */
2340         if (le16_to_cpu(data->sblock.magic) != EXT2_MAGIC)
2341                 goto fail;
2342
2343
2344         if (le32_to_cpu(data->sblock.revision_level) == 0) {
2345                 fs->inodesz = 128;
2346         } else {
2347                 debug("EXT4 features COMPAT: %08x INCOMPAT: %08x RO_COMPAT: %08x\n",
2348                       __le32_to_cpu(data->sblock.feature_compatibility),
2349                       __le32_to_cpu(data->sblock.feature_incompat),
2350                       __le32_to_cpu(data->sblock.feature_ro_compat));
2351
2352                 fs->inodesz = le16_to_cpu(data->sblock.inode_size);
2353                 fs->gdsize = le32_to_cpu(data->sblock.feature_incompat) &
2354                         EXT4_FEATURE_INCOMPAT_64BIT ?
2355                         le16_to_cpu(data->sblock.descriptor_size) : 32;
2356         }
2357
2358         debug("EXT2 rev %d, inode_size %d, descriptor size %d\n",
2359               le32_to_cpu(data->sblock.revision_level),
2360               fs->inodesz, fs->gdsize);
2361
2362         data->diropen.data = data;
2363         data->diropen.ino = 2;
2364         data->diropen.inode_read = 1;
2365         data->inode = &data->diropen.inode;
2366
2367         status = ext4fs_read_inode(data, 2, data->inode);
2368         if (status == 0)
2369                 goto fail;
2370
2371         ext4fs_root = data;
2372
2373         return 1;
2374 fail:
2375         printf("Failed to mount ext2 filesystem...\n");
2376         free(data);
2377         ext4fs_root = NULL;
2378
2379         return 0;
2380 }