fs/ext4/ext4_common.c

   1 /*
   2  * (C) Copyright 2011 - 2012 Samsung Electronics
   3  * EXT4 filesystem implementation in Uboot by
   4  * Uma Shankar <uma.shankar@samsung.com>
   5  * Manjunatha C Achar <a.manjunatha@samsung.com>
   6  *
   7  * ext4ls and ext4load : Based on ext2 ls load support in Uboot.
   8  *
   9  * (C) Copyright 2004
  10  * esd gmbh <www.esd-electronics.com>
  11  * Reinhard Arlt <reinhard.arlt@esd-electronics.com>
  12  *
  13  * based on code from grub2 fs/ext2.c and fs/fshelp.c by
  14  * GRUB  --  GRand Unified Bootloader
  15  * Copyright (C) 2003, 2004  Free Software Foundation, Inc.
  16  *
  17  * ext4write : Based on generic ext4 protocol.
  18  *
  19  * SPDX-License-Identifier:     GPL-2.0+
  20  */
  21
  22 #include <common.h>
  23 #include <ext_common.h>
  24 #include <ext4fs.h>
  25 #include <inttypes.h>
  26 #include <malloc.h>
  27 #include <memalign.h>
  28 #include <stddef.h>
  29 #include <linux/stat.h>
  30 #include <linux/time.h>
  31 #include <asm/byteorder.h>
  32 #include "ext4_common.h"
  33
  34 struct ext2_data *ext4fs_root;
  35 struct ext2fs_node *ext4fs_file;
  36 __le32 *ext4fs_indir1_block;
  37 int ext4fs_indir1_size;
  38 int ext4fs_indir1_blkno = -1;
  39 __le32 *ext4fs_indir2_block;
  40 int ext4fs_indir2_size;
  41 int ext4fs_indir2_blkno = -1;
  42
  43 __le32 *ext4fs_indir3_block;
  44 int ext4fs_indir3_size;
  45 int ext4fs_indir3_blkno = -1;
  46 struct ext2_inode *g_parent_inode;
  47 static int symlinknest;
  48
  49 #if defined(CONFIG_EXT4_WRITE)
  50 struct ext2_block_group *ext4fs_get_group_descriptor
  51         (const struct ext_filesystem *fs, uint32_t bg_idx)
  52 {
  53         return (struct ext2_block_group *)(fs->gdtable + (bg_idx * fs->gdsize));
  54 }
  55
  56 static inline void ext4fs_sb_free_inodes_dec(struct ext2_sblock *sb)
  57 {
  58         sb->free_inodes = cpu_to_le32(le32_to_cpu(sb->free_inodes) - 1);
  59 }
  60
  61 static inline void ext4fs_sb_free_blocks_dec(struct ext2_sblock *sb)
  62 {
  63         sb->free_blocks = cpu_to_le32(le32_to_cpu(sb->free_blocks) - 1);
  64 }
  65
  66 static inline void ext4fs_bg_free_inodes_dec(struct ext2_block_group *bg)
  67 {
  68         bg->free_inodes = cpu_to_le16(le16_to_cpu(bg->free_inodes) - 1);
  69 }
  70
  71 static inline void ext4fs_bg_free_blocks_dec(struct ext2_block_group *bg)
  72 {
  73         bg->free_blocks = cpu_to_le16(le16_to_cpu(bg->free_blocks) - 1);
  74 }
  75
  76 static inline void ext4fs_bg_itable_unused_dec(struct ext2_block_group *bg)
  77 {
  78         bg->bg_itable_unused = cpu_to_le16(le16_to_cpu(bg->bg_itable_unused) - 1);
  79 }
  80
  81 uint64_t ext4fs_sb_get_free_blocks(const struct ext2_sblock *sb)
  82 {
  83         uint64_t free_blocks = le32_to_cpu(sb->free_blocks);
  84         free_blocks += (uint64_t)le32_to_cpu(sb->free_blocks_high) << 32;
  85         return free_blocks;
  86 }
  87
  88 void ext4fs_sb_set_free_blocks(struct ext2_sblock *sb, uint64_t free_blocks)
  89 {
  90         sb->free_blocks = cpu_to_le32(free_blocks & 0xffffffff);
  91         sb->free_blocks_high = cpu_to_le16(free_blocks >> 32);
  92 }
  93
  94 uint32_t ext4fs_bg_get_free_blocks(const struct ext2_block_group *bg,
  95                                    const struct ext_filesystem *fs)
  96 {
  97         uint32_t free_blocks = le16_to_cpu(bg->free_blocks);
  98         if (fs->gdsize == 64)
  99                 free_blocks += le16_to_cpu(bg->free_blocks_high) << 16;
 100         return free_blocks;
 101 }
 102
 103 static inline
 104 uint32_t ext4fs_bg_get_free_inodes(const struct ext2_block_group *bg,
 105                                    const struct ext_filesystem *fs)
 106 {
 107         uint32_t free_inodes = le16_to_cpu(bg->free_inodes);
 108         if (fs->gdsize == 64)
 109                 free_inodes += le16_to_cpu(bg->free_inodes_high) << 16;
 110         return free_inodes;
 111 }
 112
 113 static inline uint16_t ext4fs_bg_get_flags(const struct ext2_block_group *bg)
 114 {
 115         return le16_to_cpu(bg->bg_flags);
 116 }
 117
 118 static inline void ext4fs_bg_set_flags(struct ext2_block_group *bg,
 119                                        uint16_t flags)
 120 {
 121         bg->bg_flags = cpu_to_le16(flags);
 122 }
 123
 124 /* Block number of the block bitmap */
 125 uint64_t ext4fs_bg_get_block_id(const struct ext2_block_group *bg,
 126                                 const struct ext_filesystem *fs)
 127 {
 128         uint64_t block_nr = le32_to_cpu(bg->block_id);
 129         if (fs->gdsize == 64)
 130                 block_nr += (uint64_t)le32_to_cpu(bg->block_id_high) << 32;
 131         return block_nr;
 132 }
 133
 134 /* Block number of the inode bitmap */
 135 uint64_t ext4fs_bg_get_inode_id(const struct ext2_block_group *bg,
 136                                 const struct ext_filesystem *fs)
 137 {
 138         uint64_t block_nr = le32_to_cpu(bg->inode_id);
 139         if (fs->gdsize == 64)
 140                 block_nr += (uint64_t)le32_to_cpu(bg->inode_id_high) << 32;
 141         return block_nr;
 142 }
 143 #endif
 144
 145 /* Block number of the inode table */
 146 uint64_t ext4fs_bg_get_inode_table_id(const struct ext2_block_group *bg,
 147                                       const struct ext_filesystem *fs)
 148 {
 149         uint64_t block_nr = le32_to_cpu(bg->inode_table_id);
 150         if (fs->gdsize == 64)
 151                 block_nr +=
 152                         (uint64_t)le32_to_cpu(bg->inode_table_id_high) << 32;
 153         return block_nr;
 154 }
 155
 156 #if defined(CONFIG_EXT4_WRITE)
 157 uint32_t ext4fs_div_roundup(uint32_t size, uint32_t n)
 158 {
 159         uint32_t res = size / n;
 160         if (res * n != size)
 161                 res++;
 162
 163         return res;
 164 }
 165
 166 void put_ext4(uint64_t off, void *buf, uint32_t size)
 167 {
 168         uint64_t startblock;
 169         uint64_t remainder;
 170         unsigned char *temp_ptr = NULL;
 171         struct ext_filesystem *fs = get_fs();
 172         int log2blksz = fs->dev_desc->log2blksz;
 173         ALLOC_CACHE_ALIGN_BUFFER(unsigned char, sec_buf, fs->dev_desc->blksz);
 174
 175         startblock = off >> log2blksz;
 176         startblock += part_offset;
 177         remainder = off & (uint64_t)(fs->dev_desc->blksz - 1);
 178
 179         if (fs->dev_desc == NULL)
 180                 return;
 181
 182         if ((startblock + (size >> log2blksz)) >
 183             (part_offset + fs->total_sect)) {
 184                 printf("part_offset is " LBAFU "\n", part_offset);
 185                 printf("total_sector is %" PRIu64 "\n", fs->total_sect);
 186                 printf("error: overflow occurs\n");
 187                 return;
 188         }
 189
 190         if (remainder) {
 191                 blk_dread(fs->dev_desc, startblock, 1, sec_buf);
 192                 temp_ptr = sec_buf;
 193                 memcpy((temp_ptr + remainder), (unsigned char *)buf, size);
 194                 blk_dwrite(fs->dev_desc, startblock, 1, sec_buf);
 195         } else {
 196                 if (size >> log2blksz != 0) {
 197                         blk_dwrite(fs->dev_desc, startblock, size >> log2blksz,
 198                                    (unsigned long *)buf);
 199                 } else {
 200                         blk_dread(fs->dev_desc, startblock, 1, sec_buf);
 201                         temp_ptr = sec_buf;
 202                         memcpy(temp_ptr, buf, size);
 203                         blk_dwrite(fs->dev_desc, startblock, 1,
 204                                    (unsigned long *)sec_buf);
 205                 }
 206         }
 207 }
 208
 209 static int _get_new_inode_no(unsigned char *buffer)
 210 {
 211         struct ext_filesystem *fs = get_fs();
 212         unsigned char input;
 213         int operand, status;
 214         int count = 1;
 215         int j = 0;
 216
 217         /* get the blocksize of the filesystem */
 218         unsigned char *ptr = buffer;
 219         while (*ptr == 255) {
 220                 ptr++;
 221                 count += 8;
 222                 if (count > le32_to_cpu(ext4fs_root->sblock.inodes_per_group))
 223                         return -1;
 224         }
 225
 226         for (j = 0; j < fs->blksz; j++) {
 227                 input = *ptr;
 228                 int i = 0;
 229                 while (i <= 7) {
 230                         operand = 1 << i;
 231                         status = input & operand;
 232                         if (status) {
 233                                 i++;
 234                                 count++;
 235                         } else {
 236                                 *ptr |= operand;
 237                                 return count;
 238                         }
 239                 }
 240                 ptr = ptr + 1;
 241         }
 242
 243         return -1;
 244 }
 245
 246 static int _get_new_blk_no(unsigned char *buffer)
 247 {
 248         int operand;
 249         int count = 0;
 250         int i;
 251         unsigned char *ptr = buffer;
 252         struct ext_filesystem *fs = get_fs();
 253
 254         while (*ptr == 255) {
 255                 ptr++;
 256                 count += 8;
 257                 if (count == (fs->blksz * 8))
 258                         return -1;
 259         }
 260
 261         if (fs->blksz == 1024)
 262                 count += 1;
 263
 264         for (i = 0; i <= 7; i++) {
 265                 operand = 1 << i;
 266                 if (*ptr & operand) {
 267                         count++;
 268                 } else {
 269                         *ptr |= operand;
 270                         return count;
 271                 }
 272         }
 273
 274         return -1;
 275 }
 276
 277 int ext4fs_set_block_bmap(long int blockno, unsigned char *buffer, int index)
 278 {
 279         int i, remainder, status;
 280         unsigned char *ptr = buffer;
 281         unsigned char operand;
 282         i = blockno / 8;
 283         remainder = blockno % 8;
 284         int blocksize = EXT2_BLOCK_SIZE(ext4fs_root);
 285
 286         i = i - (index * blocksize);
 287         if (blocksize != 1024) {
 288                 ptr = ptr + i;
 289                 operand = 1 << remainder;
 290                 status = *ptr & operand;
 291                 if (status)
 292                         return -1;
 293
 294                 *ptr = *ptr | operand;
 295                 return 0;
 296         } else {
 297                 if (remainder == 0) {
 298                         ptr = ptr + i - 1;
 299                         operand = (1 << 7);
 300                 } else {
 301                         ptr = ptr + i;
 302                         operand = (1 << (remainder - 1));
 303                 }
 304                 status = *ptr & operand;
 305                 if (status)
 306                         return -1;
 307
 308                 *ptr = *ptr | operand;
 309                 return 0;
 310         }
 311 }
 312
 313 void ext4fs_reset_block_bmap(long int blockno, unsigned char *buffer, int index)
 314 {
 315         int i, remainder, status;
 316         unsigned char *ptr = buffer;
 317         unsigned char operand;
 318         i = blockno / 8;
 319         remainder = blockno % 8;
 320         int blocksize = EXT2_BLOCK_SIZE(ext4fs_root);
 321
 322         i = i - (index * blocksize);
 323         if (blocksize != 1024) {
 324                 ptr = ptr + i;
 325                 operand = (1 << remainder);
 326                 status = *ptr & operand;
 327                 if (status)
 328                         *ptr = *ptr & ~(operand);
 329         } else {
 330                 if (remainder == 0) {
 331                         ptr = ptr + i - 1;
 332                         operand = (1 << 7);
 333                 } else {
 334                         ptr = ptr + i;
 335                         operand = (1 << (remainder - 1));
 336                 }
 337                 status = *ptr & operand;
 338                 if (status)
 339                         *ptr = *ptr & ~(operand);
 340         }
 341 }
 342
 343 int ext4fs_set_inode_bmap(int inode_no, unsigned char *buffer, int index)
 344 {
 345         int i, remainder, status;
 346         unsigned char *ptr = buffer;
 347         unsigned char operand;
 348
 349         inode_no -= (index * le32_to_cpu(ext4fs_root->sblock.inodes_per_group));
 350         i = inode_no / 8;
 351         remainder = inode_no % 8;
 352         if (remainder == 0) {
 353                 ptr = ptr + i - 1;
 354                 operand = (1 << 7);
 355         } else {
 356                 ptr = ptr + i;
 357                 operand = (1 << (remainder - 1));
 358         }
 359         status = *ptr & operand;
 360         if (status)
 361                 return -1;
 362
 363         *ptr = *ptr | operand;
 364
 365         return 0;
 366 }
 367
 368 void ext4fs_reset_inode_bmap(int inode_no, unsigned char *buffer, int index)
 369 {
 370         int i, remainder, status;
 371         unsigned char *ptr = buffer;
 372         unsigned char operand;
 373
 374         inode_no -= (index * le32_to_cpu(ext4fs_root->sblock.inodes_per_group));
 375         i = inode_no / 8;
 376         remainder = inode_no % 8;
 377         if (remainder == 0) {
 378                 ptr = ptr + i - 1;
 379                 operand = (1 << 7);
 380         } else {
 381                 ptr = ptr + i;
 382                 operand = (1 << (remainder - 1));
 383         }
 384         status = *ptr & operand;
 385         if (status)
 386                 *ptr = *ptr & ~(operand);
 387 }
 388
 389 uint16_t ext4fs_checksum_update(uint32_t i)
 390 {
 391         struct ext2_block_group *desc;
 392         struct ext_filesystem *fs = get_fs();
 393         uint16_t crc = 0;
 394         __le32 le32_i = cpu_to_le32(i);
 395
 396         desc = (struct ext2_block_group *)&fs->bgd[i];
 397         if (le32_to_cpu(fs->sb->feature_ro_compat) & EXT4_FEATURE_RO_COMPAT_GDT_CSUM) {
 398                 int offset = offsetof(struct ext2_block_group, bg_checksum);
 399
 400                 crc = ext2fs_crc16(~0, fs->sb->unique_id,
 401                                    sizeof(fs->sb->unique_id));
 402                 crc = ext2fs_crc16(crc, &le32_i, sizeof(le32_i));
 403                 crc = ext2fs_crc16(crc, desc, offset);
 404                 offset += sizeof(desc->bg_checksum);    /* skip checksum */
 405                 assert(offset == sizeof(*desc));
 406         }
 407
 408         return crc;
 409 }
 410
 411 static int check_void_in_dentry(struct ext2_dirent *dir, char *filename)
 412 {
 413         int dentry_length;
 414         int sizeof_void_space;
 415         int new_entry_byte_reqd;
 416         short padding_factor = 0;
 417
 418         if (dir->namelen % 4 != 0)
 419                 padding_factor = 4 - (dir->namelen % 4);
 420
 421         dentry_length = sizeof(struct ext2_dirent) +
 422                         dir->namelen + padding_factor;
 423         sizeof_void_space = le16_to_cpu(dir->direntlen) - dentry_length;
 424         if (sizeof_void_space == 0)
 425                 return 0;
 426
 427         padding_factor = 0;
 428         if (strlen(filename) % 4 != 0)
 429                 padding_factor = 4 - (strlen(filename) % 4);
 430
 431         new_entry_byte_reqd = strlen(filename) +
 432             sizeof(struct ext2_dirent) + padding_factor;
 433         if (sizeof_void_space >= new_entry_byte_reqd) {
 434                 dir->direntlen = cpu_to_le16(dentry_length);
 435                 return sizeof_void_space;
 436         }
 437
 438         return 0;
 439 }
 440
 441 int ext4fs_update_parent_dentry(char *filename, int file_type)
 442 {
 443         unsigned int *zero_buffer = NULL;
 444         char *root_first_block_buffer = NULL;
 445         int blk_idx;
 446         long int first_block_no_of_root = 0;
 447         int totalbytes = 0;
 448         unsigned int new_entry_byte_reqd;
 449         int sizeof_void_space = 0;
 450         int templength = 0;
 451         int inodeno = -1;
 452         int status;
 453         struct ext_filesystem *fs = get_fs();
 454         /* directory entry */
 455         struct ext2_dirent *dir;
 456         char *temp_dir = NULL;
 457         uint32_t new_blk_no;
 458         uint32_t new_size;
 459         uint32_t new_blockcnt;
 460         uint32_t directory_blocks;
 461
 462         zero_buffer = zalloc(fs->blksz);
 463         if (!zero_buffer) {
 464                 printf("No Memory\n");
 465                 return -1;
 466         }
 467         root_first_block_buffer = zalloc(fs->blksz);
 468         if (!root_first_block_buffer) {
 469                 free(zero_buffer);
 470                 printf("No Memory\n");
 471                 return -1;
 472         }
 473         new_entry_byte_reqd = ROUND(strlen(filename) +
 474                                     sizeof(struct ext2_dirent), 4);
 475 restart:
 476         directory_blocks = le32_to_cpu(g_parent_inode->size) >>
 477                 LOG2_BLOCK_SIZE(ext4fs_root);
 478         blk_idx = directory_blocks - 1;
 479
 480 restart_read:
 481         /* read the block no allocated to a file */
 482         first_block_no_of_root = read_allocated_block(g_parent_inode, blk_idx);
 483         if (first_block_no_of_root <= 0)
 484                 goto fail;
 485
 486         status = ext4fs_devread((lbaint_t)first_block_no_of_root
 487                                 * fs->sect_perblk,
 488                                 0, fs->blksz, root_first_block_buffer);
 489         if (status == 0)
 490                 goto fail;
 491
 492         if (ext4fs_log_journal(root_first_block_buffer, first_block_no_of_root))
 493                 goto fail;
 494         dir = (struct ext2_dirent *)root_first_block_buffer;
 495         totalbytes = 0;
 496
 497         while (le16_to_cpu(dir->direntlen) > 0) {
 498                 unsigned short used_len = ROUND(dir->namelen +
 499                     sizeof(struct ext2_dirent), 4);
 500
 501                 /* last entry of block */
 502                 if (fs->blksz - totalbytes == le16_to_cpu(dir->direntlen)) {
 503
 504                         /* check if new entry fits */
 505                         if ((used_len + new_entry_byte_reqd) <=
 506                             le16_to_cpu(dir->direntlen)) {
 507                                 dir->direntlen = cpu_to_le16(used_len);
 508                                 break;
 509                         } else {
 510                                 if (blk_idx > 0) {
 511                                         printf("Block full, trying previous\n");
 512                                         blk_idx--;
 513                                         goto restart_read;
 514                                 }
 515                                 printf("All blocks full: Allocate new\n");
 516
 517                                 if (le32_to_cpu(g_parent_inode->flags) &
 518                                                 EXT4_EXTENTS_FL) {
 519                                         printf("Directory uses extents\n");
 520                                         goto fail;
 521                                 }
 522                                 if (directory_blocks >= INDIRECT_BLOCKS) {
 523                                         printf("Directory exceeds limit\n");
 524                                         goto fail;
 525                                 }
 526                                 new_blk_no = ext4fs_get_new_blk_no();
 527                                 if (new_blk_no == -1) {
 528                                         printf("no block left to assign\n");
 529                                         goto fail;
 530                                 }
 531                                 put_ext4((uint64_t)new_blk_no * fs->blksz, zero_buffer, fs->blksz);
 532                                 g_parent_inode->b.blocks.
 533                                         dir_blocks[directory_blocks] =
 534                                         cpu_to_le32(new_blk_no);
 535
 536                                 new_size = le32_to_cpu(g_parent_inode->size);
 537                                 new_size += fs->blksz;
 538                                 g_parent_inode->size = cpu_to_le32(new_size);
 539
 540                                 new_blockcnt = le32_to_cpu(g_parent_inode->blockcnt);
 541                                 new_blockcnt += fs->sect_perblk;
 542                                 g_parent_inode->blockcnt = cpu_to_le32(new_blockcnt);
 543
 544                                 if (ext4fs_put_metadata
 545                                     (root_first_block_buffer,
 546                                      first_block_no_of_root))
 547                                         goto fail;
 548                                 goto restart;
 549                         }
 550                 }
 551
 552                 templength = le16_to_cpu(dir->direntlen);
 553                 totalbytes = totalbytes + templength;
 554                 sizeof_void_space = check_void_in_dentry(dir, filename);
 555                 if (sizeof_void_space)
 556                         break;
 557
 558                 dir = (struct ext2_dirent *)((char *)dir + templength);
 559         }
 560
 561         /* make a pointer ready for creating next directory entry */
 562         templength = le16_to_cpu(dir->direntlen);
 563         totalbytes = totalbytes + templength;
 564         dir = (struct ext2_dirent *)((char *)dir + templength);
 565
 566         /* get the next available inode number */
 567         inodeno = ext4fs_get_new_inode_no();
 568         if (inodeno == -1) {
 569                 printf("no inode left to assign\n");
 570                 goto fail;
 571         }
 572         dir->inode = cpu_to_le32(inodeno);
 573         if (sizeof_void_space)
 574                 dir->direntlen = cpu_to_le16(sizeof_void_space);
 575         else
 576                 dir->direntlen = cpu_to_le16(fs->blksz - totalbytes);
 577
 578         dir->namelen = strlen(filename);
 579         dir->filetype = FILETYPE_REG;   /* regular file */
 580         temp_dir = (char *)dir;
 581         temp_dir = temp_dir + sizeof(struct ext2_dirent);
 582         memcpy(temp_dir, filename, strlen(filename));
 583
 584         /* update or write  the 1st block of root inode */
 585         if (ext4fs_put_metadata(root_first_block_buffer,
 586                                 first_block_no_of_root))
 587                 goto fail;
 588
 589 fail:
 590         free(zero_buffer);
 591         free(root_first_block_buffer);
 592
 593         return inodeno;
 594 }
 595
 596 static int search_dir(struct ext2_inode *parent_inode, char *dirname)
 597 {
 598         int status;
 599         int inodeno = 0;
 600         int offset;
 601         int blk_idx;
 602         long int blknr;
 603         char *block_buffer = NULL;
 604         struct ext2_dirent *dir = NULL;
 605         struct ext_filesystem *fs = get_fs();
 606         uint32_t directory_blocks;
 607         char *direntname;
 608
 609         directory_blocks = le32_to_cpu(parent_inode->size) >>
 610                 LOG2_BLOCK_SIZE(ext4fs_root);
 611
 612         block_buffer = zalloc(fs->blksz);
 613         if (!block_buffer)
 614                 goto fail;
 615
 616         /* get the block no allocated to a file */
 617         for (blk_idx = 0; blk_idx < directory_blocks; blk_idx++) {
 618                 blknr = read_allocated_block(parent_inode, blk_idx);
 619                 if (blknr <= 0)
 620                         goto fail;
 621
 622                 /* read the directory block */
 623                 status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk,
 624                                         0, fs->blksz, (char *)block_buffer);
 625                 if (status == 0)
 626                         goto fail;
 627
 628                 offset = 0;
 629                 do {
 630                         dir = (struct ext2_dirent *)(block_buffer + offset);
 631                         direntname = (char*)(dir) + sizeof(struct ext2_dirent);
 632
 633                         int direntlen = le16_to_cpu(dir->direntlen);
 634                         if (direntlen < sizeof(struct ext2_dirent))
 635                                 break;
 636
 637                         if (dir->inode && (strlen(dirname) == dir->namelen) &&
 638                             (strncmp(dirname, direntname, dir->namelen) == 0)) {
 639                                 inodeno = le32_to_cpu(dir->inode);
 640                                 break;
 641                         }
 642
 643                         offset += direntlen;
 644
 645                 } while (offset < fs->blksz);
 646
 647                 if (inodeno > 0) {
 648                         free(block_buffer);
 649                         return inodeno;
 650                 }
 651         }
 652
 653 fail:
 654         free(block_buffer);
 655
 656         return -1;
 657 }
 658
 659 static int find_dir_depth(char *dirname)
 660 {
 661         char *token = strtok(dirname, "/");
 662         int count = 0;
 663         while (token != NULL) {
 664                 token = strtok(NULL, "/");
 665                 count++;
 666         }
 667         return count + 1 + 1;
 668         /*
 669          * for example  for string /home/temp
 670          * depth=home(1)+temp(1)+1 extra for NULL;
 671          * so count is 4;
 672          */
 673 }
 674
 675 static int parse_path(char **arr, char *dirname)
 676 {
 677         char *token = strtok(dirname, "/");
 678         int i = 0;
 679
 680         /* add root */
 681         arr[i] = zalloc(strlen("/") + 1);
 682         if (!arr[i])
 683                 return -ENOMEM;
 684         memcpy(arr[i++], "/", strlen("/"));
 685
 686         /* add each path entry after root */
 687         while (token != NULL) {
 688                 arr[i] = zalloc(strlen(token) + 1);
 689                 if (!arr[i])
 690                         return -ENOMEM;
 691                 memcpy(arr[i++], token, strlen(token));
 692                 token = strtok(NULL, "/");
 693         }
 694         arr[i] = NULL;
 695
 696         return 0;
 697 }
 698
 699 int ext4fs_iget(int inode_no, struct ext2_inode *inode)
 700 {
 701         if (ext4fs_read_inode(ext4fs_root, inode_no, inode) == 0)
 702                 return -1;
 703
 704         return 0;
 705 }
 706
 707 /*
 708  * Function: ext4fs_get_parent_inode_num
 709  * Return Value: inode Number of the parent directory of  file/Directory to be
 710  * created
 711  * dirname : Input parmater, input path name of the file/directory to be created
 712  * dname : Output parameter, to be filled with the name of the directory
 713  * extracted from dirname
 714  */
 715 int ext4fs_get_parent_inode_num(const char *dirname, char *dname, int flags)
 716 {
 717         int i;
 718         int depth = 0;
 719         int matched_inode_no;
 720         int result_inode_no = -1;
 721         char **ptr = NULL;
 722         char *depth_dirname = NULL;
 723         char *parse_dirname = NULL;
 724         struct ext2_inode *parent_inode = NULL;
 725         struct ext2_inode *first_inode = NULL;
 726         struct ext2_inode temp_inode;
 727
 728         if (*dirname != '/') {
 729                 printf("Please supply Absolute path\n");
 730                 return -1;
 731         }
 732
 733         /* TODO: input validation make equivalent to linux */
 734         depth_dirname = zalloc(strlen(dirname) + 1);
 735         if (!depth_dirname)
 736                 return -ENOMEM;
 737
 738         memcpy(depth_dirname, dirname, strlen(dirname));
 739         depth = find_dir_depth(depth_dirname);
 740         parse_dirname = zalloc(strlen(dirname) + 1);
 741         if (!parse_dirname)
 742                 goto fail;
 743         memcpy(parse_dirname, dirname, strlen(dirname));
 744
 745         /* allocate memory for each directory level */
 746         ptr = zalloc((depth) * sizeof(char *));
 747         if (!ptr)
 748                 goto fail;
 749         if (parse_path(ptr, parse_dirname))
 750                 goto fail;
 751         parent_inode = zalloc(sizeof(struct ext2_inode));
 752         if (!parent_inode)
 753                 goto fail;
 754         first_inode = zalloc(sizeof(struct ext2_inode));
 755         if (!first_inode)
 756                 goto fail;
 757         memcpy(parent_inode, ext4fs_root->inode, sizeof(struct ext2_inode));
 758         memcpy(first_inode, parent_inode, sizeof(struct ext2_inode));
 759         if (flags & F_FILE)
 760                 result_inode_no = EXT2_ROOT_INO;
 761         for (i = 1; i < depth; i++) {
 762                 matched_inode_no = search_dir(parent_inode, ptr[i]);
 763                 if (matched_inode_no == -1) {
 764                         if (ptr[i + 1] == NULL && i == 1) {
 765                                 result_inode_no = EXT2_ROOT_INO;
 766                                 goto end;
 767                         } else {
 768                                 if (ptr[i + 1] == NULL)
 769                                         break;
 770                                 printf("Invalid path\n");
 771                                 result_inode_no = -1;
 772                                 goto fail;
 773                         }
 774                 } else {
 775                         if (ptr[i + 1] != NULL) {
 776                                 memset(parent_inode, '\0',
 777                                        sizeof(struct ext2_inode));
 778                                 if (ext4fs_iget(matched_inode_no,
 779                                                 parent_inode)) {
 780                                         result_inode_no = -1;
 781                                         goto fail;
 782                                 }
 783                                 result_inode_no = matched_inode_no;
 784                         } else {
 785                                 break;
 786                         }
 787                 }
 788         }
 789
 790 end:
 791         if (i == 1)
 792                 matched_inode_no = search_dir(first_inode, ptr[i]);
 793         else
 794                 matched_inode_no = search_dir(parent_inode, ptr[i]);
 795
 796         if (matched_inode_no != -1) {
 797                 ext4fs_iget(matched_inode_no, &temp_inode);
 798                 if (le16_to_cpu(temp_inode.mode) & S_IFDIR) {
 799                         printf("It is a Directory\n");
 800                         result_inode_no = -1;
 801                         goto fail;
 802                 }
 803         }
 804
 805         if (strlen(ptr[i]) > 256) {
 806                 result_inode_no = -1;
 807                 goto fail;
 808         }
 809         memcpy(dname, ptr[i], strlen(ptr[i]));
 810
 811 fail:
 812         free(depth_dirname);
 813         free(parse_dirname);
 814         for (i = 0; i < depth; i++) {
 815                 if (!ptr[i])
 816                         break;
 817                 free(ptr[i]);
 818         }
 819         free(ptr);
 820         free(parent_inode);
 821         free(first_inode);
 822
 823         return result_inode_no;
 824 }
 825
 826 static int unlink_filename(char *filename, unsigned int blknr)
 827 {
 828         int totalbytes = 0;
 829         int templength = 0;
 830         int status, inodeno;
 831         int found = 0;
 832         char *root_first_block_buffer = NULL;
 833         struct ext2_dirent *dir = NULL;
 834         struct ext2_dirent *previous_dir = NULL;
 835         char *ptr = NULL;
 836         struct ext_filesystem *fs = get_fs();
 837         int ret = -1;
 838
 839         /* get the first block of root */
 840         root_first_block_buffer = zalloc(fs->blksz);
 841         if (!root_first_block_buffer)
 842                 return -ENOMEM;
 843         status = ext4fs_devread((lbaint_t)blknr * fs->sect_perblk, 0,
 844                                 fs->blksz, root_first_block_buffer);
 845         if (status == 0)
 846                 goto fail;
 847
 848         if (ext4fs_log_journal(root_first_block_buffer, blknr))
 849                 goto fail;
 850         dir = (struct ext2_dirent *)root_first_block_buffer;
 851         ptr = (char *)dir;
 852         totalbytes = 0;
 853         while (le16_to_cpu(dir->direntlen) >= 0) {
 854                 /*
 855                  * blocksize-totalbytes because last
 856                  * directory length i.e., *dir->direntlen
 857                  * is free availble space in the block that
 858                  * means it is a last entry of directory entry
 859                  */
 860                 if (dir->inode && (strlen(filename) == dir->namelen) &&
 861                     (strncmp(ptr + sizeof(struct ext2_dirent),
 862                              filename, dir->namelen) == 0)) {
 863                         printf("file found, deleting\n");
 864                         inodeno = le32_to_cpu(dir->inode);
 865                         if (previous_dir) {
 866                                 uint16_t new_len;
 867                                 new_len = le16_to_cpu(previous_dir->direntlen);
 868                                 new_len += le16_to_cpu(dir->direntlen);
 869                                 previous_dir->direntlen = cpu_to_le16(new_len);
 870                         } else {
 871                                 dir->inode = 0;
 872                         }
 873                         found = 1;
 874                         break;
 875                 }
 876
 877                 if (fs->blksz - totalbytes == le16_to_cpu(dir->direntlen))
 878                         break;
 879
 880                 /* traversing the each directory entry */
 881                 templength = le16_to_cpu(dir->direntlen);
 882                 totalbytes = totalbytes + templength;
 883                 previous_dir = dir;
 884                 dir = (struct ext2_dirent *)((char *)dir + templength);
 885                 ptr = (char *)dir;
 886         }
 887
 888
 889         if (found == 1) {
 890                 if (ext4fs_put_metadata(root_first_block_buffer, blknr))
 891                         goto fail;
 892                 ret = inodeno;
 893         }
 894 fail:
 895         free(root_first_block_buffer);
 896
 897         return ret;
 898 }
 899
 900 int ext4fs_filename_unlink(char *filename)
 901 {
 902         int blk_idx;
 903         long int blknr = -1;
 904         int inodeno = -1;
 905         uint32_t directory_blocks;
 906
 907         directory_blocks = le32_to_cpu(g_parent_inode->size) >>
 908                 LOG2_BLOCK_SIZE(ext4fs_root);
 909
 910         /* read the block no allocated to a file */
 911         for (blk_idx = 0; blk_idx < directory_blocks; blk_idx++) {
 912                 blknr = read_allocated_block(g_parent_inode, blk_idx);
 913                 if (blknr <= 0)
 914                         break;
 915                 inodeno = unlink_filename(filename, blknr);
 916                 if (inodeno != -1)
 917                         return inodeno;
 918         }
 919
 920         return -1;
 921 }
 922
 923 uint32_t ext4fs_get_new_blk_no(void)
 924 {
 925         short i;
 926         short status;
 927         int remainder;
 928         unsigned int bg_idx;
 929         static int prev_bg_bitmap_index = -1;
 930         unsigned int blk_per_grp = le32_to_cpu(ext4fs_root->sblock.blocks_per_group);
 931         struct ext_filesystem *fs = get_fs();
 932         char *journal_buffer = zalloc(fs->blksz);
 933         char *zero_buffer = zalloc(fs->blksz);
 934         if (!journal_buffer || !zero_buffer)
 935                 goto fail;
 936         struct ext2_block_group *bgd = (struct ext2_block_group *)fs->gdtable;
 937
 938         if (fs->first_pass_bbmap == 0) {
 939                 for (i = 0; i < fs->no_blkgrp; i++) {
 940                         if (le16_to_cpu(bgd[i].free_blocks)) {
 941                                 if (le16_to_cpu(bgd[i].bg_flags) & EXT4_BG_BLOCK_UNINIT) {
 942                                         uint16_t new_flags;
 943                                         put_ext4((uint64_t)le32_to_cpu(bgd[i].block_id) * fs->blksz,
 944                                                  zero_buffer, fs->blksz);
 945                                         new_flags = le16_to_cpu(bgd[i].bg_flags) & ~EXT4_BG_BLOCK_UNINIT;
 946                                         bgd[i].bg_flags = cpu_to_le16(new_flags);
 947                                         memcpy(fs->blk_bmaps[i], zero_buffer,
 948                                                fs->blksz);
 949                                 }
 950                                 fs->curr_blkno =
 951                                     _get_new_blk_no(fs->blk_bmaps[i]);
 952                                 if (fs->curr_blkno == -1)
 953                                         /* if block bitmap is completely fill */
 954                                         continue;
 955                                 fs->curr_blkno = fs->curr_blkno +
 956                                                 (i * fs->blksz * 8);
 957                                 fs->first_pass_bbmap++;
 958                                 ext4fs_bg_free_blocks_dec(&bgd[i]);
 959                                 ext4fs_sb_free_blocks_dec(fs->sb);
 960                                 status = ext4fs_devread(
 961                                                         (lbaint_t)le32_to_cpu(bgd[i].block_id) *
 962                                                         fs->sect_perblk, 0,
 963                                                         fs->blksz,
 964                                                         journal_buffer);
 965                                 if (status == 0)
 966                                         goto fail;
 967                                 if (ext4fs_log_journal(journal_buffer,
 968                                                         le32_to_cpu(bgd[i].block_id)))
 969                                         goto fail;
 970                                 goto success;
 971                         } else {
 972                                 debug("no space left on block group %d\n", i);
 973                         }
 974                 }
 975
 976                 goto fail;
 977         } else {
 978                 fs->curr_blkno++;
 979 restart:
 980                 /* get the blockbitmap index respective to blockno */
 981                 bg_idx = fs->curr_blkno / blk_per_grp;
 982                 if (fs->blksz == 1024) {
 983                         remainder = fs->curr_blkno % blk_per_grp;
 984                         if (!remainder)
 985                                 bg_idx--;
 986                 }
 987
 988                 /*
 989                  * To skip completely filled block group bitmaps
 990                  * Optimize the block allocation
 991                  */
 992                 if (bg_idx >= fs->no_blkgrp)
 993                         goto fail;
 994
 995                 if (bgd[bg_idx].free_blocks == 0) {
 996                         debug("block group %u is full. Skipping\n", bg_idx);
 997                         fs->curr_blkno = (bg_idx + 1) * blk_per_grp;
 998                         if (fs->blksz == 1024)
 999                                 fs->curr_blkno += 1;
1000                         goto restart;
1001                 }
1002
1003                 if (le16_to_cpu(bgd[bg_idx].bg_flags) & EXT4_BG_BLOCK_UNINIT) {
1004                         uint16_t new_flags;
1005                         put_ext4((uint64_t)le32_to_cpu(bgd[bg_idx].block_id) * fs->blksz,
1006                                  zero_buffer, fs->blksz);
1007                         memcpy(fs->blk_bmaps[bg_idx], zero_buffer, fs->blksz);
1008                         new_flags = le16_to_cpu(bgd[bg_idx].bg_flags) & ~EXT4_BG_BLOCK_UNINIT;
1009                         bgd[bg_idx].bg_flags = cpu_to_le16(new_flags);
1010                 }
1011
1012                 if (ext4fs_set_block_bmap(fs->curr_blkno, fs->blk_bmaps[bg_idx],
1013                                    bg_idx) != 0) {
1014                         debug("going for restart for the block no %ld %u\n",
1015                               fs->curr_blkno, bg_idx);
1016                         fs->curr_blkno++;
1017                         goto restart;
1018                 }
1019
1020                 /* journal backup */
1021                 if (prev_bg_bitmap_index != bg_idx) {
1022                         status = ext4fs_devread(
1023                                                 (lbaint_t)le32_to_cpu(bgd[bg_idx].block_id)
1024                                                 * fs->sect_perblk,
1025                                                 0, fs->blksz, journal_buffer);
1026                         if (status == 0)
1027                                 goto fail;
1028                         if (ext4fs_log_journal(journal_buffer,
1029                                                 le32_to_cpu(bgd[bg_idx].block_id)))
1030                                 goto fail;
1031
1032                         prev_bg_bitmap_index = bg_idx;
1033                 }
1034                 ext4fs_bg_free_blocks_dec(&bgd[bg_idx]);
1035                 ext4fs_sb_free_blocks_dec(fs->sb);
1036                 goto success;
1037         }
1038 success:
1039         free(journal_buffer);
1040         free(zero_buffer);
1041
1042         return fs->curr_blkno;
1043 fail:
1044         free(journal_buffer);
1045         free(zero_buffer);
1046
1047         return -1;
1048 }
1049
1050 int ext4fs_get_new_inode_no(void)
1051 {
1052         short i;
1053         short status;
1054         unsigned int ibmap_idx;
1055         static int prev_inode_bitmap_index = -1;
1056         unsigned int inodes_per_grp = le32_to_cpu(ext4fs_root->sblock.inodes_per_group);
1057         struct ext_filesystem *fs = get_fs();
1058         char *journal_buffer = zalloc(fs->blksz);
1059         char *zero_buffer = zalloc(fs->blksz);
1060         if (!journal_buffer || !zero_buffer)
1061                 goto fail;
1062         struct ext2_block_group *bgd = (struct ext2_block_group *)fs->gdtable;
1063         int has_gdt_chksum = le32_to_cpu(fs->sb->feature_ro_compat) &
1064                 EXT4_FEATURE_RO_COMPAT_GDT_CSUM ? 1 : 0;
1065
1066         if (fs->first_pass_ibmap == 0) {
1067                 for (i = 0; i < fs->no_blkgrp; i++) {
1068                         if (bgd[i].free_inodes) {
1069                                 if (has_gdt_chksum)
1070                                         bgd[i].bg_itable_unused =
1071                                                 bgd[i].free_inodes;
1072                                 if (le16_to_cpu(bgd[i].bg_flags) & EXT4_BG_INODE_UNINIT) {
1073                                         int new_flags;
1074                                         put_ext4((uint64_t)le32_to_cpu(bgd[i].inode_id) * fs->blksz,
1075                                                  zero_buffer, fs->blksz);
1076                                         new_flags = le16_to_cpu(bgd[i].bg_flags) & ~EXT4_BG_INODE_UNINIT;
1077                                         bgd[i].bg_flags = cpu_to_le16(new_flags);
1078                                         memcpy(fs->inode_bmaps[i],
1079                                                zero_buffer, fs->blksz);
1080                                 }
1081                                 fs->curr_inode_no =
1082                                     _get_new_inode_no(fs->inode_bmaps[i]);
1083                                 if (fs->curr_inode_no == -1)
1084                                         /* if block bitmap is completely fill */
1085                                         continue;
1086                                 fs->curr_inode_no = fs->curr_inode_no +
1087                                                         (i * inodes_per_grp);
1088                                 fs->first_pass_ibmap++;
1089                                 ext4fs_bg_free_inodes_dec(&bgd[i]);
1090                                 if (has_gdt_chksum)
1091                                         ext4fs_bg_itable_unused_dec(&bgd[i]);
1092                                 ext4fs_sb_free_inodes_dec(fs->sb);
1093                                 status = ext4fs_devread(
1094                                                         (lbaint_t)le32_to_cpu(bgd[i].inode_id) *
1095                                                         fs->sect_perblk, 0,
1096                                                         fs->blksz,
1097                                                         journal_buffer);
1098                                 if (status == 0)
1099                                         goto fail;
1100                                 if (ext4fs_log_journal(journal_buffer,
1101                                                         le32_to_cpu(bgd[i].inode_id)))
1102                                         goto fail;
1103                                 goto success;
1104                         } else
1105                                 debug("no inode left on block group %d\n", i);
1106                 }
1107                 goto fail;
1108         } else {
1109 restart:
1110                 fs->curr_inode_no++;
1111                 /* get the blockbitmap index respective to blockno */
1112                 ibmap_idx = fs->curr_inode_no / inodes_per_grp;
1113                 if (le16_to_cpu(bgd[ibmap_idx].bg_flags) & EXT4_BG_INODE_UNINIT) {
1114                         int new_flags;
1115                         put_ext4((uint64_t)le32_to_cpu(bgd[ibmap_idx].inode_id) * fs->blksz,
1116                                  zero_buffer, fs->blksz);
1117                         new_flags = le16_to_cpu(bgd[ibmap_idx].bg_flags) & ~EXT4_BG_INODE_UNINIT;
1118                         bgd[ibmap_idx].bg_flags = cpu_to_le16(new_flags);
1119                         memcpy(fs->inode_bmaps[ibmap_idx], zero_buffer,
1120                                 fs->blksz);
1121                 }
1122
1123                 if (ext4fs_set_inode_bmap(fs->curr_inode_no,
1124                                           fs->inode_bmaps[ibmap_idx],
1125                                           ibmap_idx) != 0) {
1126                         debug("going for restart for the block no %d %u\n",
1127                               fs->curr_inode_no, ibmap_idx);
1128                         goto restart;
1129                 }
1130
1131                 /* journal backup */
1132                 if (prev_inode_bitmap_index != ibmap_idx) {
1133                         memset(journal_buffer, '\0', fs->blksz);
1134                         status = ext4fs_devread(
1135                                                 (lbaint_t)le32_to_cpu(bgd[ibmap_idx].inode_id)
1136                                                 * fs->sect_perblk,
1137                                                 0, fs->blksz, journal_buffer);
1138                         if (status == 0)
1139                                 goto fail;
1140                         if (ext4fs_log_journal(journal_buffer,
1141                                                 le32_to_cpu(bgd[ibmap_idx].inode_id)))
1142                                 goto fail;
1143                         prev_inode_bitmap_index = ibmap_idx;
1144                 }
1145                 ext4fs_bg_free_inodes_dec(&bgd[ibmap_idx]);
1146                 if (has_gdt_chksum)
1147                         bgd[ibmap_idx].bg_itable_unused =
1148                                         bgd[ibmap_idx].free_inodes;
1149                 ext4fs_sb_free_inodes_dec(fs->sb);
1150                 goto success;
1151         }
1152
1153 success:
1154         free(journal_buffer);
1155         free(zero_buffer);
1156
1157         return fs->curr_inode_no;
1158 fail:
1159         free(journal_buffer);
1160         free(zero_buffer);
1161
1162         return -1;
1163
1164 }
1165
1166
1167 static void alloc_single_indirect_block(struct ext2_inode *file_inode,
1168                                         unsigned int *total_remaining_blocks,
1169                                         unsigned int *no_blks_reqd)
1170 {
1171         short i;
1172         short status;
1173         long int actual_block_no;
1174         long int si_blockno;
1175         /* si :single indirect */
1176         __le32 *si_buffer = NULL;
1177         __le32 *si_start_addr = NULL;
1178         struct ext_filesystem *fs = get_fs();
1179
1180         if (*total_remaining_blocks != 0) {
1181                 si_buffer = zalloc(fs->blksz);
1182                 if (!si_buffer) {
1183                         printf("No Memory\n");
1184                         return;
1185                 }
1186                 si_start_addr = si_buffer;
1187                 si_blockno = ext4fs_get_new_blk_no();
1188                 if (si_blockno == -1) {
1189                         printf("no block left to assign\n");
1190                         goto fail;
1191                 }
1192                 (*no_blks_reqd)++;
1193                 debug("SIPB %ld: %u\n", si_blockno, *total_remaining_blocks);
1194
1195                 status = ext4fs_devread((lbaint_t)si_blockno * fs->sect_perblk,
1196                                         0, fs->blksz, (char *)si_buffer);
1197                 memset(si_buffer, '\0', fs->blksz);
1198                 if (status == 0)
1199                         goto fail;
1200
1201                 for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
1202                         actual_block_no = ext4fs_get_new_blk_no();
1203                         if (actual_block_no == -1) {
1204                                 printf("no block left to assign\n");
1205                                 goto fail;
1206                         }
1207                         *si_buffer = cpu_to_le32(actual_block_no);
1208                         debug("SIAB %u: %u\n", *si_buffer,
1209                                 *total_remaining_blocks);
1210
1211                         si_buffer++;
1212                         (*total_remaining_blocks)--;
1213                         if (*total_remaining_blocks == 0)
1214                                 break;
1215                 }
1216
1217                 /* write the block to disk */
1218                 put_ext4(((uint64_t) ((uint64_t)si_blockno * (uint64_t)fs->blksz)),
1219                          si_start_addr, fs->blksz);
1220                 file_inode->b.blocks.indir_block = cpu_to_le32(si_blockno);
1221         }
1222 fail:
1223         free(si_start_addr);
1224 }
1225
1226 static void alloc_double_indirect_block(struct ext2_inode *file_inode,
1227                                         unsigned int *total_remaining_blocks,
1228                                         unsigned int *no_blks_reqd)
1229 {
1230         short i;
1231         short j;
1232         short status;
1233         long int actual_block_no;
1234         /* di:double indirect */
1235         long int di_blockno_parent;
1236         long int di_blockno_child;
1237         __le32 *di_parent_buffer = NULL;
1238         __le32 *di_child_buff = NULL;
1239         __le32 *di_block_start_addr = NULL;
1240         __le32 *di_child_buff_start = NULL;
1241         struct ext_filesystem *fs = get_fs();
1242
1243         if (*total_remaining_blocks != 0) {
1244                 /* double indirect parent block connecting to inode */
1245                 di_blockno_parent = ext4fs_get_new_blk_no();
1246                 if (di_blockno_parent == -1) {
1247                         printf("no block left to assign\n");
1248                         goto fail;
1249                 }
1250                 di_parent_buffer = zalloc(fs->blksz);
1251                 if (!di_parent_buffer)
1252                         goto fail;
1253
1254                 di_block_start_addr = di_parent_buffer;
1255                 (*no_blks_reqd)++;
1256                 debug("DIPB %ld: %u\n", di_blockno_parent,
1257                       *total_remaining_blocks);
1258
1259                 status = ext4fs_devread((lbaint_t)di_blockno_parent *
1260                                         fs->sect_perblk, 0,
1261                                         fs->blksz, (char *)di_parent_buffer);
1262
1263                 if (!status) {
1264                         printf("%s: Device read error!\n", __func__);
1265                         goto fail;
1266                 }
1267                 memset(di_parent_buffer, '\0', fs->blksz);
1268
1269                 /*
1270                  * start:for each double indirect parent
1271                  * block create one more block
1272                  */
1273                 for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
1274                         di_blockno_child = ext4fs_get_new_blk_no();
1275                         if (di_blockno_child == -1) {
1276                                 printf("no block left to assign\n");
1277                                 goto fail;
1278                         }
1279                         di_child_buff = zalloc(fs->blksz);
1280                         if (!di_child_buff)
1281                                 goto fail;
1282
1283                         di_child_buff_start = di_child_buff;
1284                         *di_parent_buffer = cpu_to_le32(di_blockno_child);
1285                         di_parent_buffer++;
1286                         (*no_blks_reqd)++;
1287                         debug("DICB %ld: %u\n", di_blockno_child,
1288                               *total_remaining_blocks);
1289
1290                         status = ext4fs_devread((lbaint_t)di_blockno_child *
1291                                                 fs->sect_perblk, 0,
1292                                                 fs->blksz,
1293                                                 (char *)di_child_buff);
1294
1295                         if (!status) {
1296                                 printf("%s: Device read error!\n", __func__);
1297                                 goto fail;
1298                         }
1299                         memset(di_child_buff, '\0', fs->blksz);
1300                         /* filling of actual datablocks for each child */
1301                         for (j = 0; j < (fs->blksz / sizeof(int)); j++) {
1302                                 actual_block_no = ext4fs_get_new_blk_no();
1303                                 if (actual_block_no == -1) {
1304                                         printf("no block left to assign\n");
1305                                         goto fail;
1306                                 }
1307                                 *di_child_buff = cpu_to_le32(actual_block_no);
1308                                 debug("DIAB %ld: %u\n", actual_block_no,
1309                                       *total_remaining_blocks);
1310
1311                                 di_child_buff++;
1312                                 (*total_remaining_blocks)--;
1313                                 if (*total_remaining_blocks == 0)
1314                                         break;
1315                         }
1316                         /* write the block  table */
1317                         put_ext4(((uint64_t) ((uint64_t)di_blockno_child * (uint64_t)fs->blksz)),
1318                                  di_child_buff_start, fs->blksz);
1319                         free(di_child_buff_start);
1320                         di_child_buff_start = NULL;
1321
1322                         if (*total_remaining_blocks == 0)
1323                                 break;
1324                 }
1325                 put_ext4(((uint64_t) ((uint64_t)di_blockno_parent * (uint64_t)fs->blksz)),
1326                          di_block_start_addr, fs->blksz);
1327                 file_inode->b.blocks.double_indir_block = cpu_to_le32(di_blockno_parent);
1328         }
1329 fail:
1330         free(di_block_start_addr);
1331 }
1332
1333 static void alloc_triple_indirect_block(struct ext2_inode *file_inode,
1334                                         unsigned int *total_remaining_blocks,
1335                                         unsigned int *no_blks_reqd)
1336 {
1337         short i;
1338         short j;
1339         short k;
1340         long int actual_block_no;
1341         /* ti: Triple Indirect */
1342         long int ti_gp_blockno;
1343         long int ti_parent_blockno;
1344         long int ti_child_blockno;
1345         __le32 *ti_gp_buff = NULL;
1346         __le32 *ti_parent_buff = NULL;
1347         __le32 *ti_child_buff = NULL;
1348         __le32 *ti_gp_buff_start_addr = NULL;
1349         __le32 *ti_pbuff_start_addr = NULL;
1350         __le32 *ti_cbuff_start_addr = NULL;
1351         struct ext_filesystem *fs = get_fs();
1352         if (*total_remaining_blocks != 0) {
1353                 /* triple indirect grand parent block connecting to inode */
1354                 ti_gp_blockno = ext4fs_get_new_blk_no();
1355                 if (ti_gp_blockno == -1) {
1356                         printf("no block left to assign\n");
1357                         return;
1358                 }
1359                 ti_gp_buff = zalloc(fs->blksz);
1360                 if (!ti_gp_buff)
1361                         return;
1362
1363                 ti_gp_buff_start_addr = ti_gp_buff;
1364                 (*no_blks_reqd)++;
1365                 debug("TIGPB %ld: %u\n", ti_gp_blockno,
1366                       *total_remaining_blocks);
1367
1368                 /* for each 4 byte grand parent entry create one more block */
1369                 for (i = 0; i < (fs->blksz / sizeof(int)); i++) {
1370                         ti_parent_blockno = ext4fs_get_new_blk_no();
1371                         if (ti_parent_blockno == -1) {
1372                                 printf("no block left to assign\n");
1373                                 goto fail;
1374                         }
1375                         ti_parent_buff = zalloc(fs->blksz);
1376                         if (!ti_parent_buff)
1377                                 goto fail;
1378
1379                         ti_pbuff_start_addr = ti_parent_buff;
1380                         *ti_gp_buff = cpu_to_le32(ti_parent_blockno);
1381                         ti_gp_buff++;
1382                         (*no_blks_reqd)++;
1383                         debug("TIPB %ld: %u\n", ti_parent_blockno,
1384                               *total_remaining_blocks);
1385
1386                         /* for each 4 byte entry parent create one more block */
1387                         for (j = 0; j < (fs->blksz / sizeof(int)); j++) {
1388                                 ti_child_blockno = ext4fs_get_new_blk_no();
1389                                 if (ti_child_blockno == -1) {
1390                                         printf("no block left assign\n");
1391                                         goto fail1;
1392                                 }
1393                                 ti_child_buff = zalloc(fs->blksz);
1394                                 if (!ti_child_buff)
1395                                         goto fail1;
1396
1397                                 ti_cbuff_start_addr = ti_child_buff;
1398                                 *ti_parent_buff = cpu_to_le32(ti_child_blockno);
1399                                 ti_parent_buff++;
1400                                 (*no_blks_reqd)++;
1401                                 debug("TICB %ld: %u\n", ti_parent_blockno,
1402                                       *total_remaining_blocks);
1403
1404                                 /* fill actual datablocks for each child */
1405                                 for (k = 0; k < (fs->blksz / sizeof(int));
1406                                         k++) {
1407                                         actual_block_no =
1408                                             ext4fs_get_new_blk_no();
1409                                         if (actual_block_no == -1) {
1410                                                 printf("no block left\n");
1411                                                 free(ti_cbuff_start_addr);
1412                                                 goto fail1;
1413                                         }
1414                                         *ti_child_buff = cpu_to_le32(actual_block_no);
1415                                         debug("TIAB %ld: %u\n", actual_block_no,
1416                                               *total_remaining_blocks);
1417
1418                                         ti_child_buff++;
1419                                         (*total_remaining_blocks)--;
1420                                         if (*total_remaining_blocks == 0)
1421                                                 break;
1422                                 }
1423                                 /* write the child block */
1424                                 put_ext4(((uint64_t) ((uint64_t)ti_child_blockno *
1425                                                       (uint64_t)fs->blksz)),
1426                                          ti_cbuff_start_addr, fs->blksz);
1427                                 free(ti_cbuff_start_addr);
1428
1429                                 if (*total_remaining_blocks == 0)
1430                                         break;
1431                         }
1432                         /* write the parent block */
1433                         put_ext4(((uint64_t) ((uint64_t)ti_parent_blockno * (uint64_t)fs->blksz)),
1434                                  ti_pbuff_start_addr, fs->blksz);
1435                         free(ti_pbuff_start_addr);
1436
1437                         if (*total_remaining_blocks == 0)
1438                                 break;
1439                 }
1440                 /* write the grand parent block */
1441                 put_ext4(((uint64_t) ((uint64_t)ti_gp_blockno * (uint64_t)fs->blksz)),
1442                          ti_gp_buff_start_addr, fs->blksz);
1443                 file_inode->b.blocks.triple_indir_block = cpu_to_le32(ti_gp_blockno);
1444                 free(ti_gp_buff_start_addr);
1445                 return;
1446         }
1447 fail1:
1448         free(ti_pbuff_start_addr);
1449 fail:
1450         free(ti_gp_buff_start_addr);
1451 }
1452
1453 void ext4fs_allocate_blocks(struct ext2_inode *file_inode,
1454                                 unsigned int total_remaining_blocks,
1455                                 unsigned int *total_no_of_block)
1456 {
1457         short i;
1458         long int direct_blockno;
1459         unsigned int no_blks_reqd = 0;
1460
1461         /* allocation of direct blocks */
1462         for (i = 0; total_remaining_blocks && i < INDIRECT_BLOCKS; i++) {
1463                 direct_blockno = ext4fs_get_new_blk_no();
1464                 if (direct_blockno == -1) {
1465                         printf("no block left to assign\n");
1466                         return;
1467                 }
1468                 file_inode->b.blocks.dir_blocks[i] = cpu_to_le32(direct_blockno);
1469                 debug("DB %ld: %u\n", direct_blockno, total_remaining_blocks);
1470
1471                 total_remaining_blocks--;
1472         }
1473
1474         alloc_single_indirect_block(file_inode, &total_remaining_blocks,
1475                                     &no_blks_reqd);
1476         alloc_double_indirect_block(file_inode, &total_remaining_blocks,
1477                                     &no_blks_reqd);
1478         alloc_triple_indirect_block(file_inode, &total_remaining_blocks,
1479                                     &no_blks_reqd);
1480         *total_no_of_block += no_blks_reqd;
1481 }
1482
1483 #endif
1484
1485 static struct ext4_extent_header *ext4fs_get_extent_block
1486         (struct ext2_data *data, char *buf,
1487                 struct ext4_extent_header *ext_block,
1488                 uint32_t fileblock, int log2_blksz)
1489 {
1490         struct ext4_extent_idx *index;
1491         unsigned long long block;
1492         int blksz = EXT2_BLOCK_SIZE(data);
1493         int i;
1494
1495         while (1) {
1496                 index = (struct ext4_extent_idx *)(ext_block + 1);
1497
1498                 if (le16_to_cpu(ext_block->eh_magic) != EXT4_EXT_MAGIC)
1499                         return NULL;
1500
1501                 if (ext_block->eh_depth == 0)
1502                         return ext_block;
1503                 i = -1;
1504                 do {
1505                         i++;
1506                         if (i >= le16_to_cpu(ext_block->eh_entries))
1507                                 break;
1508                 } while (fileblock >= le32_to_cpu(index[i].ei_block));
1509
1510                 if (--i < 0)
1511                         return NULL;
1512
1513                 block = le16_to_cpu(index[i].ei_leaf_hi);
1514                 block = (block << 32) + le32_to_cpu(index[i].ei_leaf_lo);
1515
1516                 if (ext4fs_devread((lbaint_t)block << log2_blksz, 0, blksz,
1517                                    buf))
1518                         ext_block = (struct ext4_extent_header *)buf;
1519                 else
1520                         return NULL;
1521         }
1522 }
1523
1524 static int ext4fs_blockgroup
1525         (struct ext2_data *data, int group, struct ext2_block_group *blkgrp)
1526 {
1527         long int blkno;
1528         unsigned int blkoff, desc_per_blk;
1529         int log2blksz = get_fs()->dev_desc->log2blksz;
1530
1531         desc_per_blk = EXT2_BLOCK_SIZE(data) / sizeof(struct ext2_block_group);
1532
1533         blkno = le32_to_cpu(data->sblock.first_data_block) + 1 +
1534                         group / desc_per_blk;
1535         blkoff = (group % desc_per_blk) * sizeof(struct ext2_block_group);
1536
1537         debug("ext4fs read %d group descriptor (blkno %ld blkoff %u)\n",
1538               group, blkno, blkoff);
1539
1540         return ext4fs_devread((lbaint_t)blkno <<
1541                               (LOG2_BLOCK_SIZE(data) - log2blksz),
1542                               blkoff, sizeof(struct ext2_block_group),
1543                               (char *)blkgrp);
1544 }
1545
1546 int ext4fs_read_inode(struct ext2_data *data, int ino, struct ext2_inode *inode)
1547 {
1548         struct ext2_block_group blkgrp;
1549         struct ext2_sblock *sblock = &data->sblock;
1550         struct ext_filesystem *fs = get_fs();
1551         int log2blksz = get_fs()->dev_desc->log2blksz;
1552         int inodes_per_block, status;
1553         long int blkno;
1554         unsigned int blkoff;
1555
1556         /* It is easier to calculate if the first inode is 0. */
1557         ino--;
1558         status = ext4fs_blockgroup(data, ino / le32_to_cpu
1559                                    (sblock->inodes_per_group), &blkgrp);
1560         if (status == 0)
1561                 return 0;
1562
1563         inodes_per_block = EXT2_BLOCK_SIZE(data) / fs->inodesz;
1564         blkno = le32_to_cpu(blkgrp.inode_table_id) +
1565             (ino % le32_to_cpu(sblock->inodes_per_group)) / inodes_per_block;
1566         blkoff = (ino % inodes_per_block) * fs->inodesz;
1567         /* Read the inode. */
1568         status = ext4fs_devread((lbaint_t)blkno << (LOG2_BLOCK_SIZE(data) -
1569                                 log2blksz), blkoff,
1570                                 sizeof(struct ext2_inode), (char *)inode);
1571         if (status == 0)
1572                 return 0;
1573
1574         return 1;
1575 }
1576
1577 long int read_allocated_block(struct ext2_inode *inode, int fileblock)
1578 {
1579         long int blknr;
1580         int blksz;
1581         int log2_blksz;
1582         int status;
1583         long int rblock;
1584         long int perblock_parent;
1585         long int perblock_child;
1586         unsigned long long start;
1587         /* get the blocksize of the filesystem */
1588         blksz = EXT2_BLOCK_SIZE(ext4fs_root);
1589         log2_blksz = LOG2_BLOCK_SIZE(ext4fs_root)
1590                 - get_fs()->dev_desc->log2blksz;
1591
1592         if (le32_to_cpu(inode->flags) & EXT4_EXTENTS_FL) {
1593                 char *buf = zalloc(blksz);
1594                 if (!buf)
1595                         return -ENOMEM;
1596                 struct ext4_extent_header *ext_block;
1597                 struct ext4_extent *extent;
1598                 int i = -1;
1599                 ext_block =
1600                         ext4fs_get_extent_block(ext4fs_root, buf,
1601                                                 (struct ext4_extent_header *)
1602                                                 inode->b.blocks.dir_blocks,
1603                                                 fileblock, log2_blksz);
1604                 if (!ext_block) {
1605                         printf("invalid extent block\n");
1606                         free(buf);
1607                         return -EINVAL;
1608                 }
1609
1610                 extent = (struct ext4_extent *)(ext_block + 1);
1611
1612                 do {
1613                         i++;
1614                         if (i >= le16_to_cpu(ext_block->eh_entries))
1615                                 break;
1616                 } while (fileblock >= le32_to_cpu(extent[i].ee_block));
1617                 if (--i >= 0) {
1618                         fileblock -= le32_to_cpu(extent[i].ee_block);
1619                         if (fileblock >= le16_to_cpu(extent[i].ee_len)) {
1620                                 free(buf);
1621                                 return 0;
1622                         }
1623
1624                         start = le16_to_cpu(extent[i].ee_start_hi);
1625                         start = (start << 32) +
1626                                         le32_to_cpu(extent[i].ee_start_lo);
1627                         free(buf);
1628                         return fileblock + start;
1629                 }
1630
1631                 printf("Extent Error\n");
1632                 free(buf);
1633                 return -1;
1634         }
1635
1636         /* Direct blocks. */
1637         if (fileblock < INDIRECT_BLOCKS)
1638                 blknr = le32_to_cpu(inode->b.blocks.dir_blocks[fileblock]);
1639
1640         /* Indirect. */
1641         else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4))) {
1642                 if (ext4fs_indir1_block == NULL) {
1643                         ext4fs_indir1_block = zalloc(blksz);
1644                         if (ext4fs_indir1_block == NULL) {
1645                                 printf("** SI ext2fs read block (indir 1)"
1646                                         "malloc failed. **\n");
1647                                 return -1;
1648                         }
1649                         ext4fs_indir1_size = blksz;
1650                         ext4fs_indir1_blkno = -1;
1651                 }
1652                 if (blksz != ext4fs_indir1_size) {
1653                         free(ext4fs_indir1_block);
1654                         ext4fs_indir1_block = NULL;
1655                         ext4fs_indir1_size = 0;
1656                         ext4fs_indir1_blkno = -1;
1657                         ext4fs_indir1_block = zalloc(blksz);
1658                         if (ext4fs_indir1_block == NULL) {
1659                                 printf("** SI ext2fs read block (indir 1):"
1660                                         "malloc failed. **\n");
1661                                 return -1;
1662                         }
1663                         ext4fs_indir1_size = blksz;
1664                 }
1665                 if ((le32_to_cpu(inode->b.blocks.indir_block) <<
1666                      log2_blksz) != ext4fs_indir1_blkno) {
1667                         status =
1668                             ext4fs_devread((lbaint_t)le32_to_cpu
1669                                            (inode->b.blocks.
1670                                             indir_block) << log2_blksz, 0,
1671                                            blksz, (char *)ext4fs_indir1_block);
1672                         if (status == 0) {
1673                                 printf("** SI ext2fs read block (indir 1)"
1674                                         "failed. **\n");
1675                                 return -1;
1676                         }
1677                         ext4fs_indir1_blkno =
1678                                 le32_to_cpu(inode->b.blocks.
1679                                                indir_block) << log2_blksz;
1680                 }
1681                 blknr = le32_to_cpu(ext4fs_indir1_block
1682                                       [fileblock - INDIRECT_BLOCKS]);
1683         }
1684         /* Double indirect. */
1685         else if (fileblock < (INDIRECT_BLOCKS + (blksz / 4 *
1686                                         (blksz / 4 + 1)))) {
1687
1688                 long int perblock = blksz / 4;
1689                 long int rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4);
1690
1691                 if (ext4fs_indir1_block == NULL) {
1692                         ext4fs_indir1_block = zalloc(blksz);
1693                         if (ext4fs_indir1_block == NULL) {
1694                                 printf("** DI ext2fs read block (indir 2 1)"
1695                                         "malloc failed. **\n");
1696                                 return -1;
1697                         }
1698                         ext4fs_indir1_size = blksz;
1699                         ext4fs_indir1_blkno = -1;
1700                 }
1701                 if (blksz != ext4fs_indir1_size) {
1702                         free(ext4fs_indir1_block);
1703                         ext4fs_indir1_block = NULL;
1704                         ext4fs_indir1_size = 0;
1705                         ext4fs_indir1_blkno = -1;
1706                         ext4fs_indir1_block = zalloc(blksz);
1707                         if (ext4fs_indir1_block == NULL) {
1708                                 printf("** DI ext2fs read block (indir 2 1)"
1709                                         "malloc failed. **\n");
1710                                 return -1;
1711                         }
1712                         ext4fs_indir1_size = blksz;
1713                 }
1714                 if ((le32_to_cpu(inode->b.blocks.double_indir_block) <<
1715                      log2_blksz) != ext4fs_indir1_blkno) {
1716                         status =
1717                             ext4fs_devread((lbaint_t)le32_to_cpu
1718                                            (inode->b.blocks.
1719                                             double_indir_block) << log2_blksz,
1720                                            0, blksz,
1721                                            (char *)ext4fs_indir1_block);
1722                         if (status == 0) {
1723                                 printf("** DI ext2fs read block (indir 2 1)"
1724                                         "failed. **\n");
1725                                 return -1;
1726                         }
1727                         ext4fs_indir1_blkno =
1728                             le32_to_cpu(inode->b.blocks.double_indir_block) <<
1729                             log2_blksz;
1730                 }
1731
1732                 if (ext4fs_indir2_block == NULL) {
1733                         ext4fs_indir2_block = zalloc(blksz);
1734                         if (ext4fs_indir2_block == NULL) {
1735                                 printf("** DI ext2fs read block (indir 2 2)"
1736                                         "malloc failed. **\n");
1737                                 return -1;
1738                         }
1739                         ext4fs_indir2_size = blksz;
1740                         ext4fs_indir2_blkno = -1;
1741                 }
1742                 if (blksz != ext4fs_indir2_size) {
1743                         free(ext4fs_indir2_block);
1744                         ext4fs_indir2_block = NULL;
1745                         ext4fs_indir2_size = 0;
1746                         ext4fs_indir2_blkno = -1;
1747                         ext4fs_indir2_block = zalloc(blksz);
1748                         if (ext4fs_indir2_block == NULL) {
1749                                 printf("** DI ext2fs read block (indir 2 2)"
1750                                         "malloc failed. **\n");
1751                                 return -1;
1752                         }
1753                         ext4fs_indir2_size = blksz;
1754                 }
1755                 if ((le32_to_cpu(ext4fs_indir1_block[rblock / perblock]) <<
1756                      log2_blksz) != ext4fs_indir2_blkno) {
1757                         status = ext4fs_devread((lbaint_t)le32_to_cpu
1758                                                 (ext4fs_indir1_block
1759                                                  [rblock /
1760                                                   perblock]) << log2_blksz, 0,
1761                                                 blksz,
1762                                                 (char *)ext4fs_indir2_block);
1763                         if (status == 0) {
1764                                 printf("** DI ext2fs read block (indir 2 2)"
1765                                         "failed. **\n");
1766                                 return -1;
1767                         }
1768                         ext4fs_indir2_blkno =
1769                             le32_to_cpu(ext4fs_indir1_block[rblock
1770                                                               /
1771                                                               perblock]) <<
1772                             log2_blksz;
1773                 }
1774                 blknr = le32_to_cpu(ext4fs_indir2_block[rblock % perblock]);
1775         }
1776         /* Tripple indirect. */
1777         else {
1778                 rblock = fileblock - (INDIRECT_BLOCKS + blksz / 4 +
1779                                       (blksz / 4 * blksz / 4));
1780                 perblock_child = blksz / 4;
1781                 perblock_parent = ((blksz / 4) * (blksz / 4));
1782
1783                 if (ext4fs_indir1_block == NULL) {
1784                         ext4fs_indir1_block = zalloc(blksz);
1785                         if (ext4fs_indir1_block == NULL) {
1786                                 printf("** TI ext2fs read block (indir 2 1)"
1787                                         "malloc failed. **\n");
1788                                 return -1;
1789                         }
1790                         ext4fs_indir1_size = blksz;
1791                         ext4fs_indir1_blkno = -1;
1792                 }
1793                 if (blksz != ext4fs_indir1_size) {
1794                         free(ext4fs_indir1_block);
1795                         ext4fs_indir1_block = NULL;
1796                         ext4fs_indir1_size = 0;
1797                         ext4fs_indir1_blkno = -1;
1798                         ext4fs_indir1_block = zalloc(blksz);
1799                         if (ext4fs_indir1_block == NULL) {
1800                                 printf("** TI ext2fs read block (indir 2 1)"
1801                                         "malloc failed. **\n");
1802                                 return -1;
1803                         }
1804                         ext4fs_indir1_size = blksz;
1805                 }
1806                 if ((le32_to_cpu(inode->b.blocks.triple_indir_block) <<
1807                      log2_blksz) != ext4fs_indir1_blkno) {
1808                         status = ext4fs_devread
1809                             ((lbaint_t)
1810                              le32_to_cpu(inode->b.blocks.triple_indir_block)
1811                              << log2_blksz, 0, blksz,
1812                              (char *)ext4fs_indir1_block);
1813                         if (status == 0) {
1814                                 printf("** TI ext2fs read block (indir 2 1)"
1815                                         "failed. **\n");
1816                                 return -1;
1817                         }
1818                         ext4fs_indir1_blkno =
1819                             le32_to_cpu(inode->b.blocks.triple_indir_block) <<
1820                             log2_blksz;
1821                 }
1822
1823                 if (ext4fs_indir2_block == NULL) {
1824                         ext4fs_indir2_block = zalloc(blksz);
1825                         if (ext4fs_indir2_block == NULL) {
1826                                 printf("** TI ext2fs read block (indir 2 2)"
1827                                         "malloc failed. **\n");
1828                                 return -1;
1829                         }
1830                         ext4fs_indir2_size = blksz;
1831                         ext4fs_indir2_blkno = -1;
1832                 }
1833                 if (blksz != ext4fs_indir2_size) {
1834                         free(ext4fs_indir2_block);
1835                         ext4fs_indir2_block = NULL;
1836                         ext4fs_indir2_size = 0;
1837                         ext4fs_indir2_blkno = -1;
1838                         ext4fs_indir2_block = zalloc(blksz);
1839                         if (ext4fs_indir2_block == NULL) {
1840                                 printf("** TI ext2fs read block (indir 2 2)"
1841                                         "malloc failed. **\n");
1842                                 return -1;
1843                         }
1844                         ext4fs_indir2_size = blksz;
1845                 }
1846                 if ((le32_to_cpu(ext4fs_indir1_block[rblock /
1847                                                        perblock_parent]) <<
1848                      log2_blksz)
1849                     != ext4fs_indir2_blkno) {
1850                         status = ext4fs_devread((lbaint_t)le32_to_cpu
1851                                                 (ext4fs_indir1_block
1852                                                  [rblock /
1853                                                   perblock_parent]) <<
1854                                                 log2_blksz, 0, blksz,
1855                                                 (char *)ext4fs_indir2_block);
1856                         if (status == 0) {
1857                                 printf("** TI ext2fs read block (indir 2 2)"
1858                                         "failed. **\n");
1859                                 return -1;
1860                         }
1861                         ext4fs_indir2_blkno =
1862                             le32_to_cpu(ext4fs_indir1_block[rblock /
1863                                                               perblock_parent])
1864                             << log2_blksz;
1865                 }
1866
1867                 if (ext4fs_indir3_block == NULL) {
1868                         ext4fs_indir3_block = zalloc(blksz);
1869                         if (ext4fs_indir3_block == NULL) {
1870                                 printf("** TI ext2fs read block (indir 2 2)"
1871                                         "malloc failed. **\n");
1872                                 return -1;
1873                         }
1874                         ext4fs_indir3_size = blksz;
1875                         ext4fs_indir3_blkno = -1;
1876                 }
1877                 if (blksz != ext4fs_indir3_size) {
1878                         free(ext4fs_indir3_block);
1879                         ext4fs_indir3_block = NULL;
1880                         ext4fs_indir3_size = 0;
1881                         ext4fs_indir3_blkno = -1;
1882                         ext4fs_indir3_block = zalloc(blksz);
1883                         if (ext4fs_indir3_block == NULL) {
1884                                 printf("** TI ext2fs read block (indir 2 2)"
1885                                         "malloc failed. **\n");
1886                                 return -1;
1887                         }
1888                         ext4fs_indir3_size = blksz;
1889                 }
1890                 if ((le32_to_cpu(ext4fs_indir2_block[rblock
1891                                                        /
1892                                                        perblock_child]) <<
1893                      log2_blksz) != ext4fs_indir3_blkno) {
1894                         status =
1895                             ext4fs_devread((lbaint_t)le32_to_cpu
1896                                            (ext4fs_indir2_block
1897                                             [(rblock / perblock_child)
1898                                              % (blksz / 4)]) << log2_blksz, 0,
1899                                            blksz, (char *)ext4fs_indir3_block);
1900                         if (status == 0) {
1901                                 printf("** TI ext2fs read block (indir 2 2)"
1902                                        "failed. **\n");
1903                                 return -1;
1904                         }
1905                         ext4fs_indir3_blkno =
1906                             le32_to_cpu(ext4fs_indir2_block[(rblock /
1907                                                                perblock_child) %
1908                                                               (blksz /
1909                                                                4)]) <<
1910                             log2_blksz;
1911                 }
1912
1913                 blknr = le32_to_cpu(ext4fs_indir3_block
1914                                       [rblock % perblock_child]);
1915         }
1916         debug("read_allocated_block %ld\n", blknr);
1917
1918         return blknr;
1919 }
1920
1921 /**
1922  * ext4fs_reinit_global() - Reinitialize values of ext4 write implementation's
1923  *                          global pointers
1924  *
1925  * This function assures that for a file with the same name but different size
1926  * the sequential store on the ext4 filesystem will be correct.
1927  *
1928  * In this function the global data, responsible for internal representation
1929  * of the ext4 data are initialized to the reset state. Without this, during
1930  * replacement of the smaller file with the bigger truncation of new file was
1931  * performed.
1932  */
1933 void ext4fs_reinit_global(void)
1934 {
1935         if (ext4fs_indir1_block != NULL) {
1936                 free(ext4fs_indir1_block);
1937                 ext4fs_indir1_block = NULL;
1938                 ext4fs_indir1_size = 0;
1939                 ext4fs_indir1_blkno = -1;
1940         }
1941         if (ext4fs_indir2_block != NULL) {
1942                 free(ext4fs_indir2_block);
1943                 ext4fs_indir2_block = NULL;
1944                 ext4fs_indir2_size = 0;
1945                 ext4fs_indir2_blkno = -1;
1946         }
1947         if (ext4fs_indir3_block != NULL) {
1948                 free(ext4fs_indir3_block);
1949                 ext4fs_indir3_block = NULL;
1950                 ext4fs_indir3_size = 0;
1951                 ext4fs_indir3_blkno = -1;
1952         }
1953 }
1954 void ext4fs_close(void)
1955 {
1956         if ((ext4fs_file != NULL) && (ext4fs_root != NULL)) {
1957                 ext4fs_free_node(ext4fs_file, &ext4fs_root->diropen);
1958                 ext4fs_file = NULL;
1959         }
1960         if (ext4fs_root != NULL) {
1961                 free(ext4fs_root);
1962                 ext4fs_root = NULL;
1963         }
1964
1965         ext4fs_reinit_global();
1966 }
1967
1968 int ext4fs_iterate_dir(struct ext2fs_node *dir, char *name,
1969                                 struct ext2fs_node **fnode, int *ftype)
1970 {
1971         unsigned int fpos = 0;
1972         int status;
1973         loff_t actread;
1974         struct ext2fs_node *diro = (struct ext2fs_node *) dir;
1975
1976 #ifdef DEBUG
1977         if (name != NULL)
1978                 printf("Iterate dir %s\n", name);
1979 #endif /* of DEBUG */
1980         if (!diro->inode_read) {
1981                 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode);
1982                 if (status == 0)
1983                         return 0;
1984         }
1985         /* Search the file.  */
1986         while (fpos < le32_to_cpu(diro->inode.size)) {
1987                 struct ext2_dirent dirent;
1988
1989                 status = ext4fs_read_file(diro, fpos,
1990                                            sizeof(struct ext2_dirent),
1991                                            (char *)&dirent, &actread);
1992                 if (status < 0)
1993                         return 0;
1994
1995                 if (dirent.direntlen == 0) {
1996                         printf("Failed to iterate over directory %s\n", name);
1997                         return 0;
1998                 }
1999
2000                 if (dirent.namelen != 0) {
2001                         char filename[dirent.namelen + 1];
2002                         struct ext2fs_node *fdiro;
2003                         int type = FILETYPE_UNKNOWN;
2004
2005                         status = ext4fs_read_file(diro,
2006                                                   fpos +
2007                                                   sizeof(struct ext2_dirent),
2008                                                   dirent.namelen, filename,
2009                                                   &actread);
2010                         if (status < 0)
2011                                 return 0;
2012
2013                         fdiro = zalloc(sizeof(struct ext2fs_node));
2014                         if (!fdiro)
2015                                 return 0;
2016
2017                         fdiro->data = diro->data;
2018                         fdiro->ino = le32_to_cpu(dirent.inode);
2019
2020                         filename[dirent.namelen] = '\0';
2021
2022                         if (dirent.filetype != FILETYPE_UNKNOWN) {
2023                                 fdiro->inode_read = 0;
2024
2025                                 if (dirent.filetype == FILETYPE_DIRECTORY)
2026                                         type = FILETYPE_DIRECTORY;
2027                                 else if (dirent.filetype == FILETYPE_SYMLINK)
2028                                         type = FILETYPE_SYMLINK;
2029                                 else if (dirent.filetype == FILETYPE_REG)
2030                                         type = FILETYPE_REG;
2031                         } else {
2032                                 status = ext4fs_read_inode(diro->data,
2033                                                            le32_to_cpu
2034                                                            (dirent.inode),
2035                                                            &fdiro->inode);
2036                                 if (status == 0) {
2037                                         free(fdiro);
2038                                         return 0;
2039                                 }
2040                                 fdiro->inode_read = 1;
2041
2042                                 if ((le16_to_cpu(fdiro->inode.mode) &
2043                                      FILETYPE_INO_MASK) ==
2044                                     FILETYPE_INO_DIRECTORY) {
2045                                         type = FILETYPE_DIRECTORY;
2046                                 } else if ((le16_to_cpu(fdiro->inode.mode)
2047                                             & FILETYPE_INO_MASK) ==
2048                                            FILETYPE_INO_SYMLINK) {
2049                                         type = FILETYPE_SYMLINK;
2050                                 } else if ((le16_to_cpu(fdiro->inode.mode)
2051                                             & FILETYPE_INO_MASK) ==
2052                                            FILETYPE_INO_REG) {
2053                                         type = FILETYPE_REG;
2054                                 }
2055                         }
2056 #ifdef DEBUG
2057                         printf("iterate >%s<\n", filename);
2058 #endif /* of DEBUG */
2059                         if ((name != NULL) && (fnode != NULL)
2060                             && (ftype != NULL)) {
2061                                 if (strcmp(filename, name) == 0) {
2062                                         *ftype = type;
2063                                         *fnode = fdiro;
2064                                         return 1;
2065                                 }
2066                         } else {
2067                                 if (fdiro->inode_read == 0) {
2068                                         status = ext4fs_read_inode(diro->data,
2069                                                                  le32_to_cpu(
2070                                                                  dirent.inode),
2071                                                                  &fdiro->inode);
2072                                         if (status == 0) {
2073                                                 free(fdiro);
2074                                                 return 0;
2075                                         }
2076                                         fdiro->inode_read = 1;
2077                                 }
2078                                 switch (type) {
2079                                 case FILETYPE_DIRECTORY:
2080                                         printf("<DIR> ");
2081                                         break;
2082                                 case FILETYPE_SYMLINK:
2083                                         printf("<SYM> ");
2084                                         break;
2085                                 case FILETYPE_REG:
2086                                         printf("      ");
2087                                         break;
2088                                 default:
2089                                         printf("< ? > ");
2090                                         break;
2091                                 }
2092                                 printf("%10u %s\n",
2093                                        le32_to_cpu(fdiro->inode.size),
2094                                         filename);
2095                         }
2096                         free(fdiro);
2097                 }
2098                 fpos += le16_to_cpu(dirent.direntlen);
2099         }
2100         return 0;
2101 }
2102
2103 static char *ext4fs_read_symlink(struct ext2fs_node *node)
2104 {
2105         char *symlink;
2106         struct ext2fs_node *diro = node;
2107         int status;
2108         loff_t actread;
2109
2110         if (!diro->inode_read) {
2111                 status = ext4fs_read_inode(diro->data, diro->ino, &diro->inode);
2112                 if (status == 0)
2113                         return NULL;
2114         }
2115         symlink = zalloc(le32_to_cpu(diro->inode.size) + 1);
2116         if (!symlink)
2117                 return NULL;
2118
2119         if (le32_to_cpu(diro->inode.size) < sizeof(diro->inode.b.symlink)) {
2120                 strncpy(symlink, diro->inode.b.symlink,
2121                          le32_to_cpu(diro->inode.size));
2122         } else {
2123                 status = ext4fs_read_file(diro, 0,
2124                                            le32_to_cpu(diro->inode.size),
2125                                            symlink, &actread);
2126                 if ((status < 0) || (actread == 0)) {
2127                         free(symlink);
2128                         return NULL;
2129                 }
2130         }
2131         symlink[le32_to_cpu(diro->inode.size)] = '\0';
2132         return symlink;
2133 }
2134
2135 static int ext4fs_find_file1(const char *currpath,
2136                              struct ext2fs_node *currroot,
2137                              struct ext2fs_node **currfound, int *foundtype)
2138 {
2139         char fpath[strlen(currpath) + 1];
2140         char *name = fpath;
2141         char *next;
2142         int status;
2143         int type = FILETYPE_DIRECTORY;
2144         struct ext2fs_node *currnode = currroot;
2145         struct ext2fs_node *oldnode = currroot;
2146
2147         strncpy(fpath, currpath, strlen(currpath) + 1);
2148
2149         /* Remove all leading slashes. */
2150         while (*name == '/')
2151                 name++;
2152
2153         if (!*name) {
2154                 *currfound = currnode;
2155                 return 1;
2156         }
2157
2158         for (;;) {
2159                 int found;
2160
2161                 /* Extract the actual part from the pathname. */
2162                 next = strchr(name, '/');
2163                 if (next) {
2164                         /* Remove all leading slashes. */
2165                         while (*next == '/')
2166                                 *(next++) = '\0';
2167                 }
2168
2169                 if (type != FILETYPE_DIRECTORY) {
2170                         ext4fs_free_node(currnode, currroot);
2171                         return 0;
2172                 }
2173
2174                 oldnode = currnode;
2175
2176                 /* Iterate over the directory. */
2177                 found = ext4fs_iterate_dir(currnode, name, &currnode, &type);
2178                 if (found == 0)
2179                         return 0;
2180
2181                 if (found == -1)
2182                         break;
2183
2184                 /* Read in the symlink and follow it. */
2185                 if (type == FILETYPE_SYMLINK) {
2186                         char *symlink;
2187
2188                         /* Test if the symlink does not loop. */
2189                         if (++symlinknest == 8) {
2190                                 ext4fs_free_node(currnode, currroot);
2191                                 ext4fs_free_node(oldnode, currroot);
2192                                 return 0;
2193                         }
2194
2195                         symlink = ext4fs_read_symlink(currnode);
2196                         ext4fs_free_node(currnode, currroot);
2197
2198                         if (!symlink) {
2199                                 ext4fs_free_node(oldnode, currroot);
2200                                 return 0;
2201                         }
2202
2203                         debug("Got symlink >%s<\n", symlink);
2204
2205                         if (symlink[0] == '/') {
2206                                 ext4fs_free_node(oldnode, currroot);
2207                                 oldnode = &ext4fs_root->diropen;
2208                         }
2209
2210                         /* Lookup the node the symlink points to. */
2211                         status = ext4fs_find_file1(symlink, oldnode,
2212                                                     &currnode, &type);
2213
2214                         free(symlink);
2215
2216                         if (status == 0) {
2217                                 ext4fs_free_node(oldnode, currroot);
2218                                 return 0;
2219                         }
2220                 }
2221
2222                 ext4fs_free_node(oldnode, currroot);
2223
2224                 /* Found the node! */
2225                 if (!next || *next == '\0') {
2226                         *currfound = currnode;
2227                         *foundtype = type;
2228                         return 1;
2229                 }
2230                 name = next;
2231         }
2232         return -1;
2233 }
2234
2235 int ext4fs_find_file(const char *path, struct ext2fs_node *rootnode,
2236         struct ext2fs_node **foundnode, int expecttype)
2237 {
2238         int status;
2239         int foundtype = FILETYPE_DIRECTORY;
2240
2241         symlinknest = 0;
2242         if (!path)
2243                 return 0;
2244
2245         status = ext4fs_find_file1(path, rootnode, foundnode, &foundtype);
2246         if (status == 0)
2247                 return 0;
2248
2249         /* Check if the node that was found was of the expected type. */
2250         if ((expecttype == FILETYPE_REG) && (foundtype != expecttype))
2251                 return 0;
2252         else if ((expecttype == FILETYPE_DIRECTORY)
2253                    && (foundtype != expecttype))
2254                 return 0;
2255
2256         return 1;
2257 }
2258
2259 int ext4fs_open(const char *filename, loff_t *len)
2260 {
2261         struct ext2fs_node *fdiro = NULL;
2262         int status;
2263
2264         if (ext4fs_root == NULL)
2265                 return -1;
2266
2267         ext4fs_file = NULL;
2268         status = ext4fs_find_file(filename, &ext4fs_root->diropen, &fdiro,
2269                                   FILETYPE_REG);
2270         if (status == 0)
2271                 goto fail;
2272
2273         if (!fdiro->inode_read) {
2274                 status = ext4fs_read_inode(fdiro->data, fdiro->ino,
2275                                 &fdiro->inode);
2276                 if (status == 0)
2277                         goto fail;
2278         }
2279         *len = le32_to_cpu(fdiro->inode.size);
2280         ext4fs_file = fdiro;
2281
2282         return 0;
2283 fail:
2284         ext4fs_free_node(fdiro, &ext4fs_root->diropen);
2285
2286         return -1;
2287 }
2288
2289 int ext4fs_mount(unsigned part_length)
2290 {
2291         struct ext2_data *data;
2292         int status;
2293         struct ext_filesystem *fs = get_fs();
2294         data = zalloc(SUPERBLOCK_SIZE);
2295         if (!data)
2296                 return 0;
2297
2298         /* Read the superblock. */
2299         status = ext4_read_superblock((char *)&data->sblock);
2300
2301         if (status == 0)
2302                 goto fail;
2303
2304         /* Make sure this is an ext2 filesystem. */
2305         if (le16_to_cpu(data->sblock.magic) != EXT2_MAGIC)
2306                 goto fail;
2307
2308         /*
2309          * The 64bit feature was enabled when metadata_csum was enabled
2310          * and we do not support metadata_csum (and cannot reliably find
2311          * files when it is set.  Refuse to mount.
2312          */
2313         if (le32_to_cpu(data->sblock.feature_incompat) & EXT4_FEATURE_INCOMPAT_64BIT) {
2314                 printf("Unsupported feature found (64bit, possibly metadata_csum), not mounting\n");
2315                 goto fail;
2316         }
2317
2318         if (le32_to_cpu(data->sblock.revision_level) == 0) {
2319                 fs->inodesz = 128;
2320         } else {
2321                 debug("EXT4 features COMPAT: %08x INCOMPAT: %08x RO_COMPAT: %08x\n",
2322                       __le32_to_cpu(data->sblock.feature_compatibility),
2323                       __le32_to_cpu(data->sblock.feature_incompat),
2324                       __le32_to_cpu(data->sblock.feature_ro_compat));
2325
2326                 fs->inodesz = le16_to_cpu(data->sblock.inode_size);
2327                 fs->gdsize = le32_to_cpu(data->sblock.feature_incompat) &
2328                         EXT4_FEATURE_INCOMPAT_64BIT ?
2329                         le16_to_cpu(data->sblock.descriptor_size) : 32;
2330         }
2331
2332         debug("EXT2 rev %d, inode_size %d, descriptor size %d\n",
2333               le32_to_cpu(data->sblock.revision_level),
2334               fs->inodesz, fs->gdsize);
2335
2336         data->diropen.data = data;
2337         data->diropen.ino = 2;
2338         data->diropen.inode_read = 1;
2339         data->inode = &data->diropen.inode;
2340
2341         status = ext4fs_read_inode(data, 2, data->inode);
2342         if (status == 0)
2343                 goto fail;
2344
2345         ext4fs_root = data;
2346
2347         return 1;
2348 fail:
2349         printf("Failed to mount ext2 filesystem...\n");
2350         free(data);
2351         ext4fs_root = NULL;
2352
2353         return 0;
2354 }