fs/ext4/ext4_common.c

   1 /*
   2  * (C) Copyright 2011 - 2012 Samsung Electronics
   3  * EXT4 filesystem implementation in Uboot by
   4  * Uma Shankar <[email protected]>
   5  * Manjunatha C Achar <[email protected]>
   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 <[email protected]>
  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 status;
 858         int inodeno = 0;
 859         int offset;
 860         char *block_buffer = NULL;
 861         struct ext2_dirent *dir = NULL;
 862         struct ext2_dirent *previous_dir;
 863         struct ext_filesystem *fs = get_fs();
 864         int ret = -1;
 865         char *direntname;
 866
 867         block_buffer = zalloc(fs->blksz);
 868         if (!block_buffer)
 869                 return -ENOMEM;
 870
 871         /* read the directory block */
 872         status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 0,
 873                                 fs->blksz, block_buffer);
 874         if (status == 0)
 875                 goto fail;
 876
 877         offset = 0;
 878         do {
 879                 previous_dir = dir;
 880                 dir = (struct ext2_dirent *)(block_buffer + offset);
 881                 direntname = (char *)(dir) + sizeof(struct ext2_dirent);
 882
 883                 int direntlen = le16_to_cpu(dir->direntlen);
 884                 if (direntlen < sizeof(struct ext2_dirent))
 885                         break;
 886
 887                 if (dir->inode && (strlen(filename) == dir->namelen) &&
 888                     (strncmp(direntname, filename, dir->namelen) == 0)) {
 889                         inodeno = le32_to_cpu(dir->inode);
 890                         break;
 891                 }
 892
 893                 offset += direntlen;
 894
 895         } while (offset < fs->blksz);
 896
 897         if (inodeno > 0) {
 898                 printf("file found, deleting\n");
 899                 if (ext4fs_log_journal(block_buffer, blknr))
 900                         goto fail;
 901
 902                 if (previous_dir) {
 903                         /* merge dir entry with predecessor */
 904                         uint16_t new_len;
 905                         new_len = le16_to_cpu(previous_dir->direntlen);
 906                         new_len += le16_to_cpu(dir->direntlen);
 907                         previous_dir->direntlen = cpu_to_le16(new_len);
 908                 } else {
 909                         /* invalidate dir entry */
 910                         dir->inode = 0;
 911                 }
 912                 if (ext4fs_put_metadata(block_buffer, blknr))
 913                         goto fail;
 914                 ret = inodeno;
 915         }
 916 fail:
 917         free(block_buffer);
 918
 919         return ret;
 920 }
 921
 922 int ext4fs_filename_unlink(char *filename)
 923 {
 924         int blk_idx;
 925         long int blknr = -1;
 926         int inodeno = -1;
 927         uint32_t directory_blocks;
 928
 929         directory_blocks = le32_to_cpu(g_parent_inode->size) >>
 930                 LOG2_BLOCK_SIZE(ext4fs_root);
 931
 932         /* read the block no allocated to a file */
 933         for (blk_idx = 0; blk_idx < directory_blocks; blk_idx++) {
 934                 blknr = read_allocated_block(g_parent_inode, blk_idx);
 935                 if (blknr <= 0)
 936                         break;
 937                 inodeno = unlink_filename(filename, blknr);
 938                 if (inodeno != -1)
 939                         return inodeno;
 940         }
 941
 942         return -1;
 943 }
 944
 945 uint32_t ext4fs_get_new_blk_no(void)
 946 {
 947         short i;
 948         short status;
 949         int remainder;
 950         unsigned int bg_idx;
 951         static int prev_bg_bitmap_index = -1;
 952         unsigned int blk_per_grp = le32_to_cpu(ext4fs_root->sblock.blocks_per_group);
 953         struct ext_filesystem *fs = get_fs();
 954         char *journal_buffer = zalloc(fs->blksz);
 955         char *zero_buffer = zalloc(fs->blksz);
 956         if (!journal_buffer || !zero_buffer)
 957                 goto fail;
 958
 959         if (fs->first_pass_bbmap == 0) {
 960                 for (i = 0; i < fs->no_blkgrp; i++) {
 961                         struct ext2_block_group *bgd = NULL;
 962                         bgd = ext4fs_get_group_descriptor(fs, i);
 963                         if (ext4fs_bg_get_free_blocks(bgd, fs)) {
 964                                 uint16_t bg_flags = ext4fs_bg_get_flags(bgd);
 965                                 uint64_t b_bitmap_blk =
 966                                         ext4fs_bg_get_block_id(bgd, fs);
 967                                 if (bg_flags & EXT4_BG_BLOCK_UNINIT) {
 968                                         memcpy(fs->blk_bmaps[i], zero_buffer,
 969                                                fs->blksz);
 970                                         put_ext4(b_bitmap_blk * fs->blksz,
 971                                                  fs->blk_bmaps[i], fs->blksz);
 972                                         bg_flags &= ~EXT4_BG_BLOCK_UNINIT;
 973                                         ext4fs_bg_set_flags(bgd, bg_flags);
 974                                 }
 975                                 fs->curr_blkno =
 976                                     _get_new_blk_no(fs->blk_bmaps[i]);
 977                                 if (fs->curr_blkno == -1)
 978                                         /* block bitmap is completely filled */
 979                                         continue;
 980                                 fs->curr_blkno = fs->curr_blkno +
 981                                                 (i * fs->blksz * 8);
 982                                 fs->first_pass_bbmap++;
 983                                 ext4fs_bg_free_blocks_dec(bgd, fs);
 984                                 ext4fs_sb_free_blocks_dec(fs->sb);
 985                                 status = ext4fs_devread(b_bitmap_blk *
 986                                                         fs->sect_perblk,
 987                                                         0, fs->blksz,
 988                                                         journal_buffer);
 989                                 if (status == 0)
 990                                         goto fail;
 991                                 if (ext4fs_log_journal(journal_buffer,
 992                                                        b_bitmap_blk))
 993                                         goto fail;
 994                                 goto success;
 995                         } else {
 996                                 debug("no space left on block group %d\n", i);
 997                         }
 998                 }
 999
1000                 goto fail;
1001         } else {
1002                 fs->curr_blkno++;
1003 restart:
1004                 /* get the blockbitmap index respective to blockno */
1005                 bg_idx = fs->curr_blkno / blk_per_grp;
1006                 if (fs->blksz == 1024) {
1007                         remainder = fs->curr_blkno % blk_per_grp;
1008                         if (!remainder)
1009                                 bg_idx--;
1010                 }
1011
1012                 /*
1013                  * To skip completely filled block group bitmaps
1014                  * Optimize the block allocation
1015                  */
1016                 if (bg_idx >= fs->no_blkgrp)
1017                         goto fail;
1018
1019                 struct ext2_block_group *bgd = NULL;
1020                 bgd = ext4fs_get_group_descriptor(fs, bg_idx);
1021                 if (ext4fs_bg_get_free_blocks(bgd, fs) == 0) {
1022                         debug("block group %u is full. Skipping\n", bg_idx);
1023                         fs->curr_blkno = (bg_idx + 1) * blk_per_grp;
1024                         if (fs->blksz == 1024)
1025                                 fs->curr_blkno += 1;
1026                         goto restart;
1027                 }
1028
1029                 uint16_t bg_flags = ext4fs_bg_get_flags(bgd);
1030                 uint64_t b_bitmap_blk = ext4fs_bg_get_block_id(bgd, fs);
1031                 if (bg_flags & EXT4_BG_BLOCK_UNINIT) {
1032                         memcpy(fs->blk_bmaps[bg_idx], zero_buffer, fs->blksz);
1033                         put_ext4(b_bitmap_blk * fs->blksz,
1034                                  zero_buffer, fs->blksz);
1035                         bg_flags &= ~EXT4_BG_BLOCK_UNINIT;
1036                         ext4fs_bg_set_flags(bgd, bg_flags);
1037                 }
1038
1039                 if (ext4fs_set_block_bmap(fs->curr_blkno, fs->blk_bmaps[bg_idx],
1040                                    bg_idx) != 0) {
1041                         debug("going for restart for the block no %ld %u\n",
1042                               fs->curr_blkno, bg_idx);
1043                         fs->curr_blkno++;
1044                         goto restart;
1045                 }
1046
1047                 /* journal backup */
1048                 if (prev_bg_bitmap_index != bg_idx) {
1049                         status = ext4fs_devread(b_bitmap_blk * fs->sect_perblk,
1050                                                 0, fs->blksz, journal_buffer);
1051                         if (status == 0)
1052                                 goto fail;
1053                         if (ext4fs_log_journal(journal_buffer, b_bitmap_blk))
1054                                 goto fail;
1055
1056                         prev_bg_bitmap_index = bg_idx;
1057                 }
1058                 ext4fs_bg_free_blocks_dec(bgd, fs);
1059                 ext4fs_sb_free_blocks_dec(fs->sb);
1060                 goto success;
1061         }
1062 success:
1063         free(journal_buffer);
1064         free(zero_buffer);
1065
1066         return fs->curr_blkno;
1067 fail:
1068         free(journal_buffer);
1069         free(zero_buffer);
1070
1071         return -1;
1072 }
1073
1074 int ext4fs_get_new_inode_no(void)
1075 {
1076         short i;
1077         short status;
1078         unsigned int ibmap_idx;
1079         static int prev_inode_bitmap_index = -1;
1080         unsigned int inodes_per_grp = le32_to_cpu(ext4fs_root->sblock.inodes_per_group);
1081         struct ext_filesystem *fs = get_fs();
1082         char *journal_buffer = zalloc(fs->blksz);
1083         char *zero_buffer = zalloc(fs->blksz);
1084         if (!journal_buffer || !zero_buffer)
1085                 goto fail;
1086         int has_gdt_chksum = le32_to_cpu(fs->sb->feature_ro_compat) &
1087                 EXT4_FEATURE_RO_COMPAT_GDT_CSUM ? 1 : 0;
1088
1089         if (fs->first_pass_ibmap == 0) {
1090                 for (i = 0; i < fs->no_blkgrp; i++) {
1091                         uint32_t free_inodes;
1092                         struct ext2_block_group *bgd = NULL;
1093                         bgd = ext4fs_get_group_descriptor(fs, i);
1094                         free_inodes = ext4fs_bg_get_free_inodes(bgd, fs);
1095                         if (free_inodes) {
1096                                 uint16_t bg_flags = ext4fs_bg_get_flags(bgd);
1097                                 uint64_t i_bitmap_blk =
1098                                         ext4fs_bg_get_inode_id(bgd, fs);
1099                                 if (has_gdt_chksum)
1100                                         bgd->bg_itable_unused = free_inodes;
1101                                 if (bg_flags & EXT4_BG_INODE_UNINIT) {
1102                                         put_ext4(i_bitmap_blk * fs->blksz,
1103                                                  zero_buffer, fs->blksz);
1104                                         bg_flags &= ~EXT4_BG_INODE_UNINIT;
1105                                         ext4fs_bg_set_flags(bgd, bg_flags);
1106                                         memcpy(fs->inode_bmaps[i],
1107                                                zero_buffer, fs->blksz);
1108                                 }
1109                                 fs->curr_inode_no =
1110                                     _get_new_inode_no(fs->inode_bmaps[i]);
1111                                 if (fs->curr_inode_no == -1)
1112                                         /* inode bitmap is completely filled */
1113                                         continue;
1114                                 fs->curr_inode_no = fs->curr_inode_no +
1115                                                         (i * inodes_per_grp);
1116                                 fs->first_pass_ibmap++;
1117                                 ext4fs_bg_free_inodes_dec(bgd, fs);
1118                                 if (has_gdt_chksum)
1119                                         ext4fs_bg_itable_unused_dec(bgd, fs);
1120                                 ext4fs_sb_free_inodes_dec(fs->sb);
1121                                 status = ext4fs_devread(i_bitmap_blk *
1122                                                         fs->sect_perblk,
1123                                                         0, fs->blksz,
1124                                                         journal_buffer);
1125                                 if (status == 0)
1126                                         goto fail;
1127                                 if (ext4fs_log_journal(journal_buffer,
1128                                                        i_bitmap_blk))
1129                                         goto fail;
1130                                 goto success;
1131                         } else
1132                                 debug("no inode left on block group %d\n", i);
1133                 }
1134                 goto fail;
1135         } else {
1136 restart:
1137                 fs->curr_inode_no++;
1138                 /* get the blockbitmap index respective to blockno */
1139                 ibmap_idx = fs->curr_inode_no / inodes_per_grp;
1140                 struct ext2_block_group *bgd =
1141                         ext4fs_get_group_descriptor(fs, ibmap_idx);
1142                 uint16_t bg_flags = ext4fs_bg_get_flags(bgd);
1143                 uint64_t i_bitmap_blk = ext4fs_bg_get_inode_id(bgd, fs);
1144
1145                 if (bg_flags & EXT4_BG_INODE_UNINIT) {
1146                         put_ext4(i_bitmap_blk * fs->blksz,
1147                                  zero_buffer, fs->blksz);
1148                         bg_flags &= ~EXT4_BG_INODE_UNINIT;
1149                         ext4fs_bg_set_flags(bgd, bg_flags);
1150                         memcpy(fs->inode_bmaps[ibmap_idx], zero_buffer,
1151                                 fs->blksz);
1152                 }
1153
1154                 if (ext4fs_set_inode_bmap(fs->curr_inode_no,
1155                                           fs->inode_bmaps[ibmap_idx],
1156                                           ibmap_idx) != 0) {
1157                         debug("going for restart for the block no %d %u\n",
1158                               fs->curr_inode_no, ibmap_idx);
1159                         goto restart;
1160                 }
1161
1162                 /* journal backup */
1163                 if (prev_inode_bitmap_index != ibmap_idx) {
1164                         status = ext4fs_devread(i_bitmap_blk * fs->sect_perblk,
1165                                                 0, fs->blksz, journal_buffer);
1166                         if (status == 0)
1167                                 goto fail;
1168                         if (ext4fs_log_journal(journal_buffer,
1169                                                 le32_to_cpu(bgd->inode_id)))
1170                                 goto fail;
1171                         prev_inode_bitmap_index = ibmap_idx;
1172                 }
1173                 ext4fs_bg_free_inodes_dec(bgd, fs);
1174                 if (has_gdt_chksum)
1175                         bgd->bg_itable_unused = bgd->free_inodes;
1176                 ext4fs_sb_free_inodes_dec(fs->sb);
1177                 goto success;
1178         }
1179
1180 success:
1181         free(journal_buffer);
1182         free(zero_buffer);
1183
1184         return fs->curr_inode_no;
1185 fail:
1186         free(journal_buffer);
1187         free(zero_buffer);
1188
1189         return -1;
1190
1191 }
1192
1193
1194 static void alloc_single_indirect_block(struct ext2_inode *file_inode,
1195                                         unsigned int *total_remaining_blocks,
1196                                         unsigned int *no_blks_reqd)
1197 {
1198         short i;
1199         short status;
1200         long int actual_block_no;
1201         long int si_blockno;
1202         /* si :single indirect */
1203         __le32 *si_buffer = NULL;
1204         __le32 *si_start_addr = NULL;
1205         struct ext_filesystem *fs = get_fs();
1206
1207         if (*total_remaining_blocks != 0) {
1208                 si_buffer = zalloc(fs->blksz);
1209                 if (!si_buffer) {
1210                         printf("No Memory\n");
1211                         return;
1212                 }
1213                 si_start_addr = si_buffer;
1214                 si_blockno = ext4fs_get_new_blk_no();
1215                 if (si_blockno == -1) {
1216                         printf("no block left to assign\n");
1217                         goto fail;
1218                 }
1219                 (*no_blks_reqd)++;
1220                 debug("SIPB %ld: %u\n", si_blockno, *total_remaining_blocks);
1221
1222                 status = ext4fs_devread((lbaint_t)si_blockno * fs->sect_perblk,
1223                                         0, fs->blksz, (char *)si_buffer);
1224                 memset(si_buffer, '\0', fs->blksz);
1225                 if (status == 0)
1226                         goto fail;
1227
1228                 for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
1229                         actual_block_no = ext4fs_get_new_blk_no();
1230                         if (actual_block_no == -1) {
1231                                 printf("no block left to assign\n");
1232                                 goto fail;
1233                         }
1234                         *si_buffer = cpu_to_le32(actual_block_no);
1235                         debug("SIAB %u: %u\n", *si_buffer,
1236                                 *total_remaining_blocks);
1237
1238                         si_buffer++;
1239                         (*total_remaining_blocks)--;
1240                         if (*total_remaining_blocks == 0)
1241                                 break;
1242                 }
1243
1244                 /* write the block to disk */
1245                 put_ext4(((uint64_t) ((uint64_t)si_blockno * (uint64_t)fs->blksz)),
1246                          si_start_addr, fs->blksz);
1247                 file_inode->b.blocks.indir_block = cpu_to_le32(si_blockno);
1248         }
1249 fail:
1250         free(si_start_addr);
1251 }
1252
1253 static void alloc_double_indirect_block(struct ext2_inode *file_inode,
1254                                         unsigned int *total_remaining_blocks,
1255                                         unsigned int *no_blks_reqd)
1256 {
1257         short i;
1258         short j;
1259         short status;
1260         long int actual_block_no;
1261         /* di:double indirect */
1262         long int di_blockno_parent;
1263         long int di_blockno_child;
1264         __le32 *di_parent_buffer = NULL;
1265         __le32 *di_child_buff = NULL;
1266         __le32 *di_block_start_addr = NULL;
1267         __le32 *di_child_buff_start = NULL;
1268         struct ext_filesystem *fs = get_fs();
1269
1270         if (*total_remaining_blocks != 0) {
1271                 /* double indirect parent block connecting to inode */
1272                 di_blockno_parent = ext4fs_get_new_blk_no();
1273                 if (di_blockno_parent == -1) {
1274                         printf("no block left to assign\n");
1275                         goto fail;
1276                 }
1277                 di_parent_buffer = zalloc(fs->blksz);
1278                 if (!di_parent_buffer)
1279                         goto fail;
1280
1281                 di_block_start_addr = di_parent_buffer;
1282                 (*no_blks_reqd)++;
1283                 debug("DIPB %ld: %u\n", di_blockno_parent,
1284                       *total_remaining_blocks);
1285
1286                 status = ext4fs_devread((lbaint_t)di_blockno_parent *
1287                                         fs->sect_perblk, 0,
1288                                         fs->blksz, (char *)di_parent_buffer);
1289
1290                 if (!status) {
1291                         printf("%s: Device read error!\n", __func__);
1292                         goto fail;
1293                 }
1294                 memset(di_parent_buffer, '\0', fs->blksz);
1295
1296                 /*
1297                  * start:for each double indirect parent
1298                  * block create one more block
1299                  */
1300                 for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
1301                         di_blockno_child = ext4fs_get_new_blk_no();
1302                         if (di_blockno_child == -1) {
1303                                 printf("no block left to assign\n");
1304                                 goto fail;
1305                         }
1306                         di_child_buff = zalloc(fs->blksz);
1307                         if (!di_child_buff)
1308                                 goto fail;
1309
1310                         di_child_buff_start = di_child_buff;
1311                         *di_parent_buffer = cpu_to_le32(di_blockno_child);
1312                         di_parent_buffer++;
1313                         (*no_blks_reqd)++;
1314                         debug("DICB %ld: %u\n", di_blockno_child,
1315                               *total_remaining_blocks);
1316
1317                         status = ext4fs_devread((lbaint_t)di_blockno_child *
1318                                                 fs->sect_perblk, 0,
1319                                                 fs->blksz,
1320                                                 (char *)di_child_buff);
1321
1322                         if (!status) {
1323                                 printf("%s: Device read error!\n", __func__);
1324                                 goto fail;
1325                         }
1326                         memset(di_child_buff, '\0', fs->blksz);
1327                         /* filling of actual datablocks for each child */
1328                         for (j = 0; j < (fs->blksz / sizeof(int)); j++) {
1329                                 actual_block_no = ext4fs_get_new_blk_no();
1330                                 if (actual_block_no == -1) {
1331                                         printf("no block left to assign\n");
1332                                         goto fail;
1333                                 }
1334                                 *di_child_buff = cpu_to_le32(actual_block_no);
1335                                 debug("DIAB %ld: %u\n", actual_block_no,
1336                                       *total_remaining_blocks);
1337
1338                                 di_child_buff++;
1339                                 (*total_remaining_blocks)--;
1340                                 if (*total_remaining_blocks == 0)
1341                                         break;
1342                         }
1343                         /* write the block  table */
1344                         put_ext4(((uint64_t) ((uint64_t)di_blockno_child * (uint64_t)fs->blksz)),
1345                                  di_child_buff_start, fs->blksz);
1346                         free(di_child_buff_start);
1347                         di_child_buff_start = NULL;
1348
1349                         if (*total_remaining_blocks == 0)
1350                                 break;
1351                 }
1352                 put_ext4(((uint64_t) ((uint64_t)di_blockno_parent * (uint64_t)fs->blksz)),
1353                          di_block_start_addr, fs->blksz);
1354                 file_inode->b.blocks.double_indir_block = cpu_to_le32(di_blockno_parent);
1355         }
1356 fail:
1357         free(di_block_start_addr);
1358 }
1359
1360 static void alloc_triple_indirect_block(struct ext2_inode *file_inode,
1361                                         unsigned int *total_remaining_blocks,
1362                                         unsigned int *no_blks_reqd)
1363 {
1364         short i;
1365         short j;
1366         short k;
1367         long int actual_block_no;
1368         /* ti: Triple Indirect */
1369         long int ti_gp_blockno;
1370         long int ti_parent_blockno;
1371         long int ti_child_blockno;
1372         __le32 *ti_gp_buff = NULL;
1373         __le32 *ti_parent_buff = NULL;
1374         __le32 *ti_child_buff = NULL;
1375         __le32 *ti_gp_buff_start_addr = NULL;
1376         __le32 *ti_pbuff_start_addr = NULL;
1377         __le32 *ti_cbuff_start_addr = NULL;
1378         struct ext_filesystem *fs = get_fs();
1379         if (*total_remaining_blocks != 0) {
1380                 /* triple indirect grand parent block connecting to inode */
1381                 ti_gp_blockno = ext4fs_get_new_blk_no();
1382                 if (ti_gp_blockno == -1) {
1383                         printf("no block left to assign\n");
1384                         return;
1385                 }
1386                 ti_gp_buff = zalloc(fs->blksz);
1387                 if (!ti_gp_buff)
1388                         return;
1389
1390                 ti_gp_buff_start_addr = ti_gp_buff;
1391                 (*no_blks_reqd)++;
1392                 debug("TIGPB %ld: %u\n", ti_gp_blockno,
1393                       *total_remaining_blocks);
1394
1395                 /* for each 4 byte grand parent entry create one more block */
1396                 for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
1397                         ti_parent_blockno = ext4fs_get_new_blk_no();
1398                         if (ti_parent_blockno == -1) {
1399                                 printf("no block left to assign\n");
1400                                 goto fail;
1401                         }
1402                         ti_parent_buff = zalloc(fs->blksz);
1403                         if (!ti_parent_buff)
1404                                 goto fail;
1405
1406                         ti_pbuff_start_addr = ti_parent_buff;
1407                         *ti_gp_buff = cpu_to_le32(ti_parent_blockno);
1408                         ti_gp_buff++;
1409                         (*no_blks_reqd)++;
1410                         debug("TIPB %ld: %u\n", ti_parent_blockno,
1411                               *total_remaining_blocks);
1412
1413                         /* for each 4 byte entry parent create one more block */
1414                         for (j = 0; j < (fs->blksz / sizeof(int)); j++) {
1415                                 ti_child_blockno = ext4fs_get_new_blk_no();
1416                                 if (ti_child_blockno == -1) {
1417                                         printf("no block left assign\n");
1418                                         goto fail1;
1419                                 }
1420                                 ti_child_buff = zalloc(fs->blksz);
1421                                 if (!ti_child_buff)
1422                                         goto fail1;
1423
1424                                 ti_cbuff_start_addr = ti_child_buff;
1425                                 *ti_parent_buff = cpu_to_le32(ti_child_blockno);
1426                                 ti_parent_buff++;
1427                                 (*no_blks_reqd)++;
1428                                 debug("TICB %ld: %u\n", ti_parent_blockno,
1429                                       *total_remaining_blocks);
1430
1431                                 /* fill actual datablocks for each child */
1432                                 for (k = 0; k < (fs->blksz / sizeof(int));
1433                                         k++) {
1434                                         actual_block_no =
1435                                             ext4fs_get_new_blk_no();
1436                                         if (actual_block_no == -1) {
1437                                                 printf("no block left\n");
1438                                                 free(ti_cbuff_start_addr);
1439                                                 goto fail1;
1440                                         }
1441                                         *ti_child_buff = cpu_to_le32(actual_block_no);
1442                                         debug("TIAB %ld: %u\n", actual_block_no,
1443                                               *total_remaining_blocks);
1444
1445                                         ti_child_buff++;
1446                                         (*total_remaining_blocks)--;
1447                                         if (*total_remaining_blocks == 0)
1448                                                 break;
1449                                 }
1450                                 /* write the child block */
1451                                 put_ext4(((uint64_t) ((uint64_t)ti_child_blockno *
1452                                                       (uint64_t)fs->blksz)),
1453                                          ti_cbuff_start_addr, fs->blksz);
1454                                 free(ti_cbuff_start_addr);
1455
1456                                 if (*total_remaining_blocks == 0)
1457                                         break;
1458                         }
1459                         /* write the parent block */
1460                         put_ext4(((uint64_t) ((uint64_t)ti_parent_blockno * (uint64_t)fs->blksz)),
1461                                  ti_pbuff_start_addr, fs->blksz);
1462                         free(ti_pbuff_start_addr);
1463
1464                         if (*total_remaining_blocks == 0)
1465                                 break;
1466                 }
1467                 /* write the grand parent block */
1468                 put_ext4(((uint64_t) ((uint64_t)ti_gp_blockno * (uint64_t)fs->blksz)),
1469                          ti_gp_buff_start_addr, fs->blksz);
1470                 file_inode->b.blocks.triple_indir_block = cpu_to_le32(ti_gp_blockno);
1471                 free(ti_gp_buff_start_addr);
1472                 return;
1473         }
1474 fail1:
1475         free(ti_pbuff_start_addr);
1476 fail:
1477         free(ti_gp_buff_start_addr);
1478 }
1479
1480 void ext4fs_allocate_blocks(struct ext2_inode *file_inode,
1481                                 unsigned int total_remaining_blocks,
1482                                 unsigned int *total_no_of_block)
1483 {
1484         short i;
1485         long int direct_blockno;
1486         unsigned int no_blks_reqd = 0;
1487
1488         /* allocation of direct blocks */
1489         for (i = 0; total_remaining_blocks && i < INDIRECT_BLOCKS; i++) {
1490                 direct_blockno = ext4fs_get_new_blk_no();
1491                 if (direct_blockno == -1) {
1492                         printf("no block left to assign\n");
1493                         return;
1494                 }
1495                 file_inode->b.blocks.dir_blocks[i] = cpu_to_le32(direct_blockno);
1496                 debug("DB %ld: %u\n", direct_blockno, total_remaining_blocks);
1497
1498                 total_remaining_blocks--;
1499         }
1500
1501         alloc_single_indirect_block(file_inode, &total_remaining_blocks,
1502                                     &no_blks_reqd);
1503         alloc_double_indirect_block(file_inode, &total_remaining_blocks,
1504                                     &no_blks_reqd);
1505         alloc_triple_indirect_block(file_inode, &total_remaining_blocks,
1506                                     &no_blks_reqd);
1507         *total_no_of_block += no_blks_reqd;
1508 }
1509
1510 #endif
1511
1512 static struct ext4_extent_header *ext4fs_get_extent_block
1513         (struct ext2_data *data, char *buf,
1514                 struct ext4_extent_header *ext_block,
1515                 uint32_t fileblock, int log2_blksz)
1516 {
1517         struct ext4_extent_idx *index;
1518         unsigned long long block;
1519         int blksz = EXT2_BLOCK_SIZE(data);
1520         int i;
1521
1522         while (1) {
1523                 index = (struct ext4_extent_idx *)(ext_block + 1);
1524
1525                 if (le16_to_cpu(ext_block->eh_magic) != EXT4_EXT_MAGIC)
1526                         return NULL;
1527
1528                 if (ext_block->eh_depth == 0)
1529                         return ext_block;
1530                 i = -1;
1531                 do {
1532                         i++;
1533                         if (i >= le16_to_cpu(ext_block->eh_entries))
1534                                 break;
1535                 } while (fileblock >= le32_to_cpu(index[i].ei_block));
1536
1537                 if (--i < 0)
1538                         return NULL;
1539
1540                 block = le16_to_cpu(index[i].ei_leaf_hi);
1541                 block = (block << 32) + le32_to_cpu(index[i].ei_leaf_lo);
1542
1543                 if (ext4fs_devread((lbaint_t)block << log2_blksz, 0, blksz,
1544                                    buf))
1545                         ext_block = (struct ext4_extent_header *)buf;
1546                 else
1547                         return NULL;
1548         }
1549 }
1550
1551 static int ext4fs_blockgroup
1552         (struct ext2_data *data, int group, struct ext2_block_group *blkgrp)
1553 {
1554         long int blkno;
1555         unsigned int blkoff, desc_per_blk;
1556         int log2blksz = get_fs()->dev_desc->log2blksz;
1557         int desc_size = get_fs()->gdsize;
1558
1559         desc_per_blk = EXT2_BLOCK_SIZE(data) / desc_size;
1560
1561         blkno = le32_to_cpu(data->sblock.first_data_block) + 1 +
1562                         group / desc_per_blk;
1563         blkoff = (group % desc_per_blk) * desc_size;
1564
1565         debug("ext4fs read %d group descriptor (blkno %ld blkoff %u)\n",
1566               group, blkno, blkoff);
1567
1568         return ext4fs_devread((lbaint_t)blkno <<
1569                               (LOG2_BLOCK_SIZE(data) - log2blksz),
1570                               blkoff, desc_size, (char *)blkgrp);
1571 }
1572
1573 int ext4fs_read_inode(struct ext2_data *data, int ino, struct ext2_inode *inode)
1574 {
1575         struct ext2_block_group blkgrp;
1576         struct ext2_sblock *sblock = &data->sblock;
1577         struct ext_filesystem *fs = get_fs();
1578         int log2blksz = get_fs()->dev_desc->log2blksz;
1579         int inodes_per_block, status;
1580         long int blkno;
1581         unsigned int blkoff;
1582
1583         /* It is easier to calculate if the first inode is 0. */
1584         ino--;
1585         status = ext4fs_blockgroup(data, ino / le32_to_cpu
1586                                    (sblock->inodes_per_group), &blkgrp);
1587         if (status == 0)
1588                 return 0;
1589
1590         inodes_per_block = EXT2_BLOCK_SIZE(data) / fs->inodesz;
1591         blkno = ext4fs_bg_get_inode_table_id(&blkgrp, fs) +
1592             (ino % le32_to_cpu(sblock->inodes_per_group)) / inodes_per_block;
1593         blkoff = (ino % inodes_per_block) * fs->inodesz;
1594         /* Read the inode. */
1595         status = ext4fs_devread((lbaint_t)blkno << (LOG2_BLOCK_SIZE(data) -
1596                                 log2blksz), blkoff,
1597                                 sizeof(struct ext2_inode), (char *)inode);
1598         if (status == 0)
1599                 return 0;
1600
1601         return 1;
1602 }
1603
1604 long int read_allocated_block(struct ext2_inode *inode, int fileblock)
1605 {
1606         long int blknr;
1607         int blksz;
1608         int log2_blksz;
1609         int status;
1610         long int rblock;
1611         long int perblock_parent;
1612         long int perblock_child;
1613         unsigned long long start;
1614         /* get the blocksize of the filesystem */
1615         blksz = EXT2_BLOCK_SIZE(ext4fs_root);
1616         log2_blksz = LOG2_BLOCK_SIZE(ext4fs_root)
1617                 - get_fs()->dev_desc->log2blksz;
1618
1619         if (le32_to_cpu(inode->flags) & EXT4_EXTENTS_FL) {
1620                 long int startblock, endblock;
1621                 char *buf = zalloc(blksz);
1622                 if (!buf)
1623                         return -ENOMEM;
1624                 struct ext4_extent_header *ext_block;
1625                 struct ext4_extent *extent;
1626                 int i;
1627                 ext_block =
1628                         ext4fs_get_extent_block(ext4fs_root, buf,
1629                                                 (struct ext4_extent_header *)
1630                                                 inode->b.blocks.dir_blocks,
1631                                                 fileblock, log2_blksz);
1632                 if (!ext_block) {
1633                         printf("invalid extent block\n");
1634                         free(buf);
1635                         return -EINVAL;
1636                 }
1637
1638                 extent = (struct ext4_extent *)(ext_block + 1);
1639
1640                 for (i = 0; i < le16_to_cpu(ext_block->eh_entries); i++) {
1641                         startblock = le32_to_cpu(extent[i].ee_block);
1642                         endblock = startblock + le16_to_cpu(extent[i].ee_len);
1643
1644                         if (startblock > fileblock) {
1645                                 /* Sparse file */
1646                                 free(buf);
1647                                 return 0;
1648
1649                         } else if (fileblock < endblock) {
1650                                 start = le16_to_cpu(extent[i].ee_start_hi);
1651                                 start = (start << 32) +
1652                                         le32_to_cpu(extent[i].ee_start_lo);
1653                                 free(buf);
1654                                 return (fileblock - startblock) + start;
1655                         }
1656                 }
1657
1658                 free(buf);
1659                 return 0;
1660         }
1661
1662         /* Direct blocks. */
1663         if (fileblock < INDIRECT_BLOCKS)
1664                 blknr = le32_to_cpu(inode->b.blocks.dir_blocks[fileblock]);
1665
1666         /* Indirect. */
1667         else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4))) {
1668                 if (ext4fs_indir1_block == NULL) {
1669                         ext4fs_indir1_block = zalloc(blksz);
1670                         if (ext4fs_indir1_block == NULL) {
1671                                 printf("** SI ext2fs read block (indir 1)"
1672                                         "malloc failed. **\n");
1673                                 return -1;
1674                         }
1675                         ext4fs_indir1_size = blksz;
1676                         ext4fs_indir1_blkno = -1;
1677                 }
1678                 if (blksz != ext4fs_indir1_size) {
1679                         free(ext4fs_indir1_block);
1680                         ext4fs_indir1_block = NULL;
1681                         ext4fs_indir1_size = 0;
1682                         ext4fs_indir1_blkno = -1;
1683                         ext4fs_indir1_block = zalloc(blksz);
1684                         if (ext4fs_indir1_block == NULL) {
1685                                 printf("** SI ext2fs read block (indir 1):"
1686                                         "malloc failed. **\n");
1687                                 return -1;
1688                         }
1689                         ext4fs_indir1_size = blksz;
1690                 }
1691                 if ((le32_to_cpu(inode->b.blocks.indir_block) <<
1692                      log2_blksz) != ext4fs_indir1_blkno) {
1693                         status =
1694                             ext4fs_devread((lbaint_t)le32_to_cpu
1695                                            (inode->b.blocks.
1696                                             indir_block) << log2_blksz, 0,
1697                                            blksz, (char *)ext4fs_indir1_block);
1698                         if (status == 0) {
1699                                 printf("** SI ext2fs read block (indir 1)"
1700                                         "failed. **\n");
1701                                 return -1;
1702                         }
1703                         ext4fs_indir1_blkno =
1704                                 le32_to_cpu(inode->b.blocks.
1705                                                indir_block) << log2_blksz;
1706                 }
1707                 blknr = le32_to_cpu(ext4fs_indir1_block
1708                                       [fileblock - INDIRECT_BLOCKS]);
1709         }
1710         /* Double indirect. */
1711         else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4 *
1712                                         (blksz / 4 + 1)))) {
1713
1714                 long int perblock = blksz / 4;
1715                 long int rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4);
1716
1717                 if (ext4fs_indir1_block == NULL) {
1718                         ext4fs_indir1_block = zalloc(blksz);
1719                         if (ext4fs_indir1_block == NULL) {
1720                                 printf("** DI ext2fs read block (indir 2 1)"
1721                                         "malloc failed. **\n");
1722                                 return -1;
1723                         }
1724                         ext4fs_indir1_size = blksz;
1725                         ext4fs_indir1_blkno = -1;
1726                 }
1727                 if (blksz != ext4fs_indir1_size) {
1728                         free(ext4fs_indir1_block);
1729                         ext4fs_indir1_block = NULL;
1730                         ext4fs_indir1_size = 0;
1731                         ext4fs_indir1_blkno = -1;
1732                         ext4fs_indir1_block = zalloc(blksz);
1733                         if (ext4fs_indir1_block == NULL) {
1734                                 printf("** DI ext2fs read block (indir 2 1)"
1735                                         "malloc failed. **\n");
1736                                 return -1;
1737                         }
1738                         ext4fs_indir1_size = blksz;
1739                 }
1740                 if ((le32_to_cpu(inode->b.blocks.double_indir_block) <<
1741                      log2_blksz) != ext4fs_indir1_blkno) {
1742                         status =
1743                             ext4fs_devread((lbaint_t)le32_to_cpu
1744                                            (inode->b.blocks.
1745                                             double_indir_block) << log2_blksz,
1746                                            0, blksz,
1747                                            (char *)ext4fs_indir1_block);
1748                         if (status == 0) {
1749                                 printf("** DI ext2fs read block (indir 2 1)"
1750                                         "failed. **\n");
1751                                 return -1;
1752                         }
1753                         ext4fs_indir1_blkno =
1754                             le32_to_cpu(inode->b.blocks.double_indir_block) <<
1755                             log2_blksz;
1756                 }
1757
1758                 if (ext4fs_indir2_block == NULL) {
1759                         ext4fs_indir2_block = zalloc(blksz);
1760                         if (ext4fs_indir2_block == NULL) {
1761                                 printf("** DI ext2fs read block (indir 2 2)"
1762                                         "malloc failed. **\n");
1763                                 return -1;
1764                         }
1765                         ext4fs_indir2_size = blksz;
1766                         ext4fs_indir2_blkno = -1;
1767                 }
1768                 if (blksz != ext4fs_indir2_size) {
1769                         free(ext4fs_indir2_block);
1770                         ext4fs_indir2_block = NULL;
1771                         ext4fs_indir2_size = 0;
1772                         ext4fs_indir2_blkno = -1;
1773                         ext4fs_indir2_block = zalloc(blksz);
1774                         if (ext4fs_indir2_block == NULL) {
1775                                 printf("** DI ext2fs read block (indir 2 2)"
1776                                         "malloc failed. **\n");
1777                                 return -1;
1778                         }
1779                         ext4fs_indir2_size = blksz;
1780                 }
1781                 if ((le32_to_cpu(ext4fs_indir1_block[rblock / perblock]) <<
1782                      log2_blksz) != ext4fs_indir2_blkno) {
1783                         status = ext4fs_devread((lbaint_t)le32_to_cpu
1784                                                 (ext4fs_indir1_block
1785                                                  [rblock /
1786                                                   perblock]) << log2_blksz, 0,
1787                                                 blksz,
1788                                                 (char *)ext4fs_indir2_block);
1789                         if (status == 0) {
1790                                 printf("** DI ext2fs read block (indir 2 2)"
1791                                         "failed. **\n");
1792                                 return -1;
1793                         }
1794                         ext4fs_indir2_blkno =
1795                             le32_to_cpu(ext4fs_indir1_block[rblock
1796                                                               /
1797                                                               perblock]) <<
1798                             log2_blksz;
1799                 }
1800                 blknr = le32_to_cpu(ext4fs_indir2_block[rblock % perblock]);
1801         }
1802         /* Tripple indirect. */
1803         else {
1804                 rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4 +
1805                                       (blksz / 4 * blksz / 4));
1806                 perblock_child = blksz / 4;
1807                 perblock_parent = ((blksz / 4) * (blksz / 4));
1808
1809                 if (ext4fs_indir1_block == NULL) {
1810                         ext4fs_indir1_block = zalloc(blksz);
1811                         if (ext4fs_indir1_block == NULL) {
1812                                 printf("** TI ext2fs read block (indir 2 1)"
1813                                         "malloc failed. **\n");
1814                                 return -1;
1815                         }
1816                         ext4fs_indir1_size = blksz;
1817                         ext4fs_indir1_blkno = -1;
1818                 }
1819                 if (blksz != ext4fs_indir1_size) {
1820                         free(ext4fs_indir1_block);
1821                         ext4fs_indir1_block = NULL;
1822                         ext4fs_indir1_size = 0;
1823                         ext4fs_indir1_blkno = -1;
1824                         ext4fs_indir1_block = zalloc(blksz);
1825                         if (ext4fs_indir1_block == NULL) {
1826                                 printf("** TI ext2fs read block (indir 2 1)"
1827                                         "malloc failed. **\n");
1828                                 return -1;
1829                         }
1830                         ext4fs_indir1_size = blksz;
1831                 }
1832                 if ((le32_to_cpu(inode->b.blocks.triple_indir_block) <<
1833                      log2_blksz) != ext4fs_indir1_blkno) {
1834                         status = ext4fs_devread
1835                             ((lbaint_t)
1836                              le32_to_cpu(inode->b.blocks.triple_indir_block)
1837                              << log2_blksz, 0, blksz,
1838                              (char *)ext4fs_indir1_block);
1839                         if (status == 0) {
1840                                 printf("** TI ext2fs read block (indir 2 1)"
1841                                         "failed. **\n");
1842                                 return -1;
1843                         }
1844                         ext4fs_indir1_blkno =
1845                             le32_to_cpu(inode->b.blocks.triple_indir_block) <<
1846                             log2_blksz;
1847                 }
1848
1849                 if (ext4fs_indir2_block == NULL) {
1850                         ext4fs_indir2_block = zalloc(blksz);
1851                         if (ext4fs_indir2_block == NULL) {
1852                                 printf("** TI ext2fs read block (indir 2 2)"
1853                                         "malloc failed. **\n");
1854                                 return -1;
1855                         }
1856                         ext4fs_indir2_size = blksz;
1857                         ext4fs_indir2_blkno = -1;
1858                 }
1859                 if (blksz != ext4fs_indir2_size) {
1860                         free(ext4fs_indir2_block);
1861                         ext4fs_indir2_block = NULL;
1862                         ext4fs_indir2_size = 0;
1863                         ext4fs_indir2_blkno = -1;
1864                         ext4fs_indir2_block = zalloc(blksz);
1865                         if (ext4fs_indir2_block == NULL) {
1866                                 printf("** TI ext2fs read block (indir 2 2)"
1867                                         "malloc failed. **\n");
1868                                 return -1;
1869                         }
1870                         ext4fs_indir2_size = blksz;
1871                 }
1872                 if ((le32_to_cpu(ext4fs_indir1_block[rblock /
1873                                                        perblock_parent]) <<
1874                      log2_blksz)
1875                     != ext4fs_indir2_blkno) {
1876                         status = ext4fs_devread((lbaint_t)le32_to_cpu
1877                                                 (ext4fs_indir1_block
1878                                                  [rblock /
1879                                                   perblock_parent]) <<
1880                                                 log2_blksz, 0, blksz,
1881                                                 (char *)ext4fs_indir2_block);
1882                         if (status == 0) {
1883                                 printf("** TI ext2fs read block (indir 2 2)"
1884                                         "failed. **\n");
1885                                 return -1;
1886                         }
1887                         ext4fs_indir2_blkno =
1888                             le32_to_cpu(ext4fs_indir1_block[rblock /
1889                                                               perblock_parent])
1890                             << log2_blksz;
1891                 }
1892
1893                 if (ext4fs_indir3_block == NULL) {
1894                         ext4fs_indir3_block = zalloc(blksz);
1895                         if (ext4fs_indir3_block == NULL) {
1896                                 printf("** TI ext2fs read block (indir 2 2)"
1897                                         "malloc failed. **\n");
1898                                 return -1;
1899                         }
1900                         ext4fs_indir3_size = blksz;
1901                         ext4fs_indir3_blkno = -1;
1902                 }
1903                 if (blksz != ext4fs_indir3_size) {
1904                         free(ext4fs_indir3_block);
1905                         ext4fs_indir3_block = NULL;
1906                         ext4fs_indir3_size = 0;
1907                         ext4fs_indir3_blkno = -1;
1908                         ext4fs_indir3_block = zalloc(blksz);
1909                         if (ext4fs_indir3_block == NULL) {
1910                                 printf("** TI ext2fs read block (indir 2 2)"
1911                                         "malloc failed. **\n");
1912                                 return -1;
1913                         }
1914                         ext4fs_indir3_size = blksz;
1915                 }
1916                 if ((le32_to_cpu(ext4fs_indir2_block[rblock
1917                                                        /
1918                                                        perblock_child]) <<
1919                      log2_blksz) != ext4fs_indir3_blkno) {
1920                         status =
1921                             ext4fs_devread((lbaint_t)le32_to_cpu
1922                                            (ext4fs_indir2_block
1923                                             [(rblock / perblock_child)
1924                                              % (blksz / 4)]) << log2_blksz, 0,
1925                                            blksz, (char *)ext4fs_indir3_block);
1926                         if (status == 0) {
1927                                 printf("** TI ext2fs read block (indir 2 2)"
1928                                        "failed. **\n");
1929                                 return -1;
1930                         }
1931                         ext4fs_indir3_blkno =
1932                             le32_to_cpu(ext4fs_indir2_block[(rblock /
1933                                                                perblock_child) %
1934                                                               (blksz /
1935                                                                4)]) <<
1936                             log2_blksz;
1937                 }
1938
1939                 blknr = le32_to_cpu(ext4fs_indir3_block
1940                                       [rblock % perblock_child]);
1941         }
1942         debug("read_allocated_block %ld\n", blknr);
1943
1944         return blknr;
1945 }
1946
1947 /**
1948  * ext4fs_reinit_global() - Reinitialize values of ext4 write implementation's
1949  *                          global pointers
1950  *
1951  * This function assures that for a file with the same name but different size
1952  * the sequential store on the ext4 filesystem will be correct.
1953  *
1954  * In this function the global data, responsible for internal representation
1955  * of the ext4 data are initialized to the reset state. Without this, during
1956  * replacement of the smaller file with the bigger truncation of new file was
1957  * performed.
1958  */
1959 void ext4fs_reinit_global(void)
1960 {
1961         if (ext4fs_indir1_block != NULL) {
1962                 free(ext4fs_indir1_block);
1963                 ext4fs_indir1_block = NULL;
1964                 ext4fs_indir1_size = 0;
1965                 ext4fs_indir1_blkno = -1;
1966         }
1967         if (ext4fs_indir2_block != NULL) {
1968                 free(ext4fs_indir2_block);
1969                 ext4fs_indir2_block = NULL;
1970                 ext4fs_indir2_size = 0;
1971                 ext4fs_indir2_blkno = -1;
1972         }
1973         if (ext4fs_indir3_block != NULL) {
1974                 free(ext4fs_indir3_block);
1975                 ext4fs_indir3_block = NULL;
1976                 ext4fs_indir3_size = 0;
1977                 ext4fs_indir3_blkno = -1;
1978         }
1979 }
1980 void ext4fs_close(void)
1981 {
1982         if ((ext4fs_file != NULL) && (ext4fs_root != NULL)) {
1983                 ext4fs_free_node(ext4fs_file, &ext4fs_root->diropen);
1984                 ext4fs_file = NULL;
1985         }
1986         if (ext4fs_root != NULL) {
1987                 free(ext4fs_root);
1988                 ext4fs_root = NULL;
1989         }
1990
1991         ext4fs_reinit_global();
1992 }
1993
1994 int ext4fs_iterate_dir(struct ext2fs_node *dir, char *name,
1995                                 struct ext2fs_node **fnode, int *ftype)
1996 {
1997         unsigned int fpos = 0;
1998         int status;
1999         loff_t actread;
2000         struct ext2fs_node *diro = (struct ext2fs_node *) dir;
2001
2002 #ifdef DEBUG
2003         if (name != NULL)
2004                 printf("Iterate dir %s\n", name);
2005 #endif /* of DEBUG */
2006         if (!diro->inode_read) {
2007                 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode);
2008                 if (status == 0)
2009                         return 0;
2010         }
2011         /* Search the file.  */
2012         while (fpos < le32_to_cpu(diro->inode.size)) {
2013                 struct ext2_dirent dirent;
2014
2015                 status = ext4fs_read_file(diro, fpos,
2016                                            sizeof(struct ext2_dirent),
2017                                            (char *)&dirent, &actread);
2018                 if (status < 0)
2019                         return 0;
2020
2021                 if (dirent.direntlen == 0) {
2022                         printf("Failed to iterate over directory %s\n", name);
2023                         return 0;
2024                 }
2025
2026                 if (dirent.namelen != 0) {
2027                         char filename[dirent.namelen + 1];
2028                         struct ext2fs_node *fdiro;
2029                         int type = FILETYPE_UNKNOWN;
2030
2031                         status = ext4fs_read_file(diro,
2032                                                   fpos +
2033                                                   sizeof(struct ext2_dirent),
2034                                                   dirent.namelen, filename,
2035                                                   &actread);
2036                         if (status < 0)
2037                                 return 0;
2038
2039                         fdiro = zalloc(sizeof(struct ext2fs_node));
2040                         if (!fdiro)
2041                                 return 0;
2042
2043                         fdiro->data = diro->data;
2044                         fdiro->ino = le32_to_cpu(dirent.inode);
2045
2046                         filename[dirent.namelen] = '\0';
2047
2048                         if (dirent.filetype != FILETYPE_UNKNOWN) {
2049                                 fdiro->inode_read = 0;
2050
2051                                 if (dirent.filetype == FILETYPE_DIRECTORY)
2052                                         type = FILETYPE_DIRECTORY;
2053                                 else if (dirent.filetype == FILETYPE_SYMLINK)
2054                                         type = FILETYPE_SYMLINK;
2055                                 else if (dirent.filetype == FILETYPE_REG)
2056                                         type = FILETYPE_REG;
2057                         } else {
2058                                 status = ext4fs_read_inode(diro->data,
2059                                                            le32_to_cpu
2060                                                            (dirent.inode),
2061                                                            &fdiro->inode);
2062                                 if (status == 0) {
2063                                         free(fdiro);
2064                                         return 0;
2065                                 }
2066                                 fdiro->inode_read = 1;
2067
2068                                 if ((le16_to_cpu(fdiro->inode.mode) &
2069                                      FILETYPE_INO_MASK) ==
2070                                     FILETYPE_INO_DIRECTORY) {
2071                                         type = FILETYPE_DIRECTORY;
2072                                 } else if ((le16_to_cpu(fdiro->inode.mode)
2073                                             & FILETYPE_INO_MASK) ==
2074                                            FILETYPE_INO_SYMLINK) {
2075                                         type = FILETYPE_SYMLINK;
2076                                 } else if ((le16_to_cpu(fdiro->inode.mode)
2077                                             & FILETYPE_INO_MASK) ==
2078                                            FILETYPE_INO_REG) {
2079                                         type = FILETYPE_REG;
2080                                 }
2081                         }
2082 #ifdef DEBUG
2083                         printf("iterate >%s<\n", filename);
2084 #endif /* of DEBUG */
2085                         if ((name != NULL) && (fnode != NULL)
2086                             && (ftype != NULL)) {
2087                                 if (strcmp(filename, name) == 0) {
2088                                         *ftype = type;
2089                                         *fnode = fdiro;
2090                                         return 1;
2091                                 }
2092                         } else {
2093                                 if (fdiro->inode_read == 0) {
2094                                         status = ext4fs_read_inode(diro->data,
2095                                                                  le32_to_cpu(
2096                                                                  dirent.inode),
2097                                                                  &fdiro->inode);
2098                                         if (status == 0) {
2099                                                 free(fdiro);
2100                                                 return 0;
2101                                         }
2102                                         fdiro->inode_read = 1;
2103                                 }
2104                                 switch (type) {
2105                                 case FILETYPE_DIRECTORY:
2106                                         printf("<DIR> ");
2107                                         break;
2108                                 case FILETYPE_SYMLINK:
2109                                         printf("<SYM> ");
2110                                         break;
2111                                 case FILETYPE_REG:
2112                                         printf("      ");
2113                                         break;
2114                                 default:
2115                                         printf("< ? > ");
2116                                         break;
2117                                 }
2118                                 printf("%10u %s\n",
2119                                        le32_to_cpu(fdiro->inode.size),
2120                                         filename);
2121                         }
2122                         free(fdiro);
2123                 }
2124                 fpos += le16_to_cpu(dirent.direntlen);
2125         }
2126         return 0;
2127 }
2128
2129 static char *ext4fs_read_symlink(struct ext2fs_node *node)
2130 {
2131         char *symlink;
2132         struct ext2fs_node *diro = node;
2133         int status;
2134         loff_t actread;
2135
2136         if (!diro->inode_read) {
2137                 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode);
2138                 if (status == 0)
2139                         return NULL;
2140         }
2141         symlink = zalloc(le32_to_cpu(diro->inode.size) + 1);
2142         if (!symlink)
2143                 return NULL;
2144
2145         if (le32_to_cpu(diro->inode.size) < sizeof(diro->inode.b.symlink)) {
2146                 strncpy(symlink, diro->inode.b.symlink,
2147                          le32_to_cpu(diro->inode.size));
2148         } else {
2149                 status = ext4fs_read_file(diro, 0,
2150                                            le32_to_cpu(diro->inode.size),
2151                                            symlink, &actread);
2152                 if ((status < 0) || (actread == 0)) {
2153                         free(symlink);
2154                         return NULL;
2155                 }
2156         }
2157         symlink[le32_to_cpu(diro->inode.size)] = '\0';
2158         return symlink;
2159 }
2160
2161 static int ext4fs_find_file1(const char *currpath,
2162                              struct ext2fs_node *currroot,
2163                              struct ext2fs_node **currfound, int *foundtype)
2164 {
2165         char fpath[strlen(currpath) + 1];
2166         char *name = fpath;
2167         char *next;
2168         int status;
2169         int type = FILETYPE_DIRECTORY;
2170         struct ext2fs_node *currnode = currroot;
2171         struct ext2fs_node *oldnode = currroot;
2172
2173         strncpy(fpath, currpath, strlen(currpath) + 1);
2174
2175         /* Remove all leading slashes. */
2176         while (*name == '/')
2177                 name++;
2178
2179         if (!*name) {
2180                 *currfound = currnode;
2181                 return 1;
2182         }
2183
2184         for (;;) {
2185                 int found;
2186
2187                 /* Extract the actual part from the pathname. */
2188                 next = strchr(name, '/');
2189                 if (next) {
2190                         /* Remove all leading slashes. */
2191                         while (*next == '/')
2192                                 *(next++) = '\0';
2193                 }
2194
2195                 if (type != FILETYPE_DIRECTORY) {
2196                         ext4fs_free_node(currnode, currroot);
2197                         return 0;
2198                 }
2199
2200                 oldnode = currnode;
2201
2202                 /* Iterate over the directory. */
2203                 found = ext4fs_iterate_dir(currnode, name, &currnode, &type);
2204                 if (found == 0)
2205                         return 0;
2206
2207                 if (found == -1)
2208                         break;
2209
2210                 /* Read in the symlink and follow it. */
2211                 if (type == FILETYPE_SYMLINK) {
2212                         char *symlink;
2213
2214                         /* Test if the symlink does not loop. */
2215                         if (++symlinknest == 8) {
2216                                 ext4fs_free_node(currnode, currroot);
2217                                 ext4fs_free_node(oldnode, currroot);
2218                                 return 0;
2219                         }
2220
2221                         symlink = ext4fs_read_symlink(currnode);
2222                         ext4fs_free_node(currnode, currroot);
2223
2224                         if (!symlink) {
2225                                 ext4fs_free_node(oldnode, currroot);
2226                                 return 0;
2227                         }
2228
2229                         debug("Got symlink >%s<\n", symlink);
2230
2231                         if (symlink[0] == '/') {
2232                                 ext4fs_free_node(oldnode, currroot);
2233                                 oldnode = &ext4fs_root->diropen;
2234                         }
2235
2236                         /* Lookup the node the symlink points to. */
2237                         status = ext4fs_find_file1(symlink, oldnode,
2238                                                     &currnode, &type);
2239
2240                         free(symlink);
2241
2242                         if (status == 0) {
2243                                 ext4fs_free_node(oldnode, currroot);
2244                                 return 0;
2245                         }
2246                 }
2247
2248                 ext4fs_free_node(oldnode, currroot);
2249
2250                 /* Found the node! */
2251                 if (!next || *next == '\0') {
2252                         *currfound = currnode;
2253                         *foundtype = type;
2254                         return 1;
2255                 }
2256                 name = next;
2257         }
2258         return -1;
2259 }
2260
2261 int ext4fs_find_file(const char *path, struct ext2fs_node *rootnode,
2262         struct ext2fs_node **foundnode, int expecttype)
2263 {
2264         int status;
2265         int foundtype = FILETYPE_DIRECTORY;
2266
2267         symlinknest = 0;
2268         if (!path)
2269                 return 0;
2270
2271         status = ext4fs_find_file1(path, rootnode, foundnode, &foundtype);
2272         if (status == 0)
2273                 return 0;
2274
2275         /* Check if the node that was found was of the expected type. */
2276         if ((expecttype == FILETYPE_REG) && (foundtype != expecttype))
2277                 return 0;
2278         else if ((expecttype == FILETYPE_DIRECTORY)
2279                    && (foundtype != expecttype))
2280                 return 0;
2281
2282         return 1;
2283 }
2284
2285 int ext4fs_open(const char *filename, loff_t *len)
2286 {
2287         struct ext2fs_node *fdiro = NULL;
2288         int status;
2289
2290         if (ext4fs_root == NULL)
2291                 return -1;
2292
2293         ext4fs_file = NULL;
2294         status = ext4fs_find_file(filename, &ext4fs_root->diropen, &fdiro,
2295                                   FILETYPE_REG);
2296         if (status == 0)
2297                 goto fail;
2298
2299         if (!fdiro->inode_read) {
2300                 status = ext4fs_read_inode(fdiro->data, fdiro->ino,
2301                                 &fdiro->inode);
2302                 if (status == 0)
2303                         goto fail;
2304         }
2305         *len = le32_to_cpu(fdiro->inode.size);
2306         ext4fs_file = fdiro;
2307
2308         return 0;
2309 fail:
2310         ext4fs_free_node(fdiro, &ext4fs_root->diropen);
2311
2312         return -1;
2313 }
2314
2315 int ext4fs_mount(unsigned part_length)
2316 {
2317         struct ext2_data *data;
2318         int status;
2319         struct ext_filesystem *fs = get_fs();
2320         data = zalloc(SUPERBLOCK_SIZE);
2321         if (!data)
2322                 return 0;
2323
2324         /* Read the superblock. */
2325         status = ext4_read_superblock((char *)&data->sblock);
2326
2327         if (status == 0)
2328                 goto fail;
2329
2330         /* Make sure this is an ext2 filesystem. */
2331         if (le16_to_cpu(data->sblock.magic) != EXT2_MAGIC)
2332                 goto fail;
2333
2334
2335         if (le32_to_cpu(data->sblock.revision_level) == 0) {
2336                 fs->inodesz = 128;
2337                 fs->gdsize = 32;
2338         } else {
2339                 debug("EXT4 features COMPAT: %08x INCOMPAT: %08x RO_COMPAT: %08x\n",
2340                       __le32_to_cpu(data->sblock.feature_compatibility),
2341                       __le32_to_cpu(data->sblock.feature_incompat),
2342                       __le32_to_cpu(data->sblock.feature_ro_compat));
2343
2344                 fs->inodesz = le16_to_cpu(data->sblock.inode_size);
2345                 fs->gdsize = le32_to_cpu(data->sblock.feature_incompat) &
2346                         EXT4_FEATURE_INCOMPAT_64BIT ?
2347                         le16_to_cpu(data->sblock.descriptor_size) : 32;
2348         }
2349
2350         debug("EXT2 rev %d, inode_size %d, descriptor size %d\n",
2351               le32_to_cpu(data->sblock.revision_level),
2352               fs->inodesz, fs->gdsize);
2353
2354         data->diropen.data = data;
2355         data->diropen.ino = 2;
2356         data->diropen.inode_read = 1;
2357         data->inode = &data->diropen.inode;
2358
2359         status = ext4fs_read_inode(data, 2, data->inode);
2360         if (status == 0)
2361                 goto fail;
2362
2363         ext4fs_root = data;
2364
2365         return 1;
2366 fail:
2367         printf("Failed to mount ext2 filesystem...\n");
2368         free(data);
2369         ext4fs_root = NULL;
2370
2371         return 0;
2372 }