fs/fat/fat.c

   1 /*
   2  * fat.c
   3  *
   4  * R/O (V)FAT 12/16/32 filesystem implementation by Marcus Sundberg
   5  *
   6  * 2002-07-28 - rjones@nexus-tech.net - ported to ppcboot v1.1.6
   7  * 2003-03-10 - kharris@nexus-tech.net - ported to uboot
   8  *
   9  * SPDX-License-Identifier:     GPL-2.0+
  10  */
  11
  12 #include <common.h>
  13 #include <config.h>
  14 #include <exports.h>
  15 #include <fat.h>
  16 #include <asm/byteorder.h>
  17 #include <part.h>
  18 #include <malloc.h>
  19 #include <linux/compiler.h>
  20 #include <linux/ctype.h>
  21
  22 #ifdef CONFIG_SUPPORT_VFAT
  23 static const int vfat_enabled = 1;
  24 #else
  25 static const int vfat_enabled = 0;
  26 #endif
  27
  28 /*
  29  * Convert a string to lowercase.
  30  */
  31 static void downcase(char *str)
  32 {
  33         while (*str != '\0') {
  34                 *str = tolower(*str);
  35                 str++;
  36         }
  37 }
  38
  39 static block_dev_desc_t *cur_dev;
  40 static disk_partition_t cur_part_info;
  41
  42 #define DOS_BOOT_MAGIC_OFFSET   0x1fe
  43 #define DOS_FS_TYPE_OFFSET      0x36
  44 #define DOS_FS32_TYPE_OFFSET    0x52
  45
  46 static int disk_read(__u32 block, __u32 nr_blocks, void *buf)
  47 {
  48         if (!cur_dev || !cur_dev->block_read)
  49                 return -1;
  50
  51         return cur_dev->block_read(cur_dev->dev,
  52                         cur_part_info.start + block, nr_blocks, buf);
  53 }
  54
  55 int fat_set_blk_dev(block_dev_desc_t *dev_desc, disk_partition_t *info)
  56 {
  57         ALLOC_CACHE_ALIGN_BUFFER(unsigned char, buffer, dev_desc->blksz);
  58
  59         cur_dev = dev_desc;
  60         cur_part_info = *info;
  61
  62         /* Make sure it has a valid FAT header */
  63         if (disk_read(0, 1, buffer) != 1) {
  64                 cur_dev = NULL;
  65                 return -1;
  66         }
  67
  68         /* Check if it's actually a DOS volume */
  69         if (memcmp(buffer + DOS_BOOT_MAGIC_OFFSET, "\x55\xAA", 2)) {
  70                 cur_dev = NULL;
  71                 return -1;
  72         }
  73
  74         /* Check for FAT12/FAT16/FAT32 filesystem */
  75         if (!memcmp(buffer + DOS_FS_TYPE_OFFSET, "FAT", 3))
  76                 return 0;
  77         if (!memcmp(buffer + DOS_FS32_TYPE_OFFSET, "FAT32", 5))
  78                 return 0;
  79
  80         cur_dev = NULL;
  81         return -1;
  82 }
  83
  84 int fat_register_device(block_dev_desc_t *dev_desc, int part_no)
  85 {
  86         disk_partition_t info;
  87
  88         /* First close any currently found FAT filesystem */
  89         cur_dev = NULL;
  90
  91         /* Read the partition table, if present */
  92         if (get_partition_info(dev_desc, part_no, &info)) {
  93                 if (part_no != 0) {
  94                         printf("** Partition %d not valid on device %d **\n",
  95                                         part_no, dev_desc->dev);
  96                         return -1;
  97                 }
  98
  99                 info.start = 0;
 100                 info.size = dev_desc->lba;
 101                 info.blksz = dev_desc->blksz;
 102                 info.name[0] = 0;
 103                 info.type[0] = 0;
 104                 info.bootable = 0;
 105 #ifdef CONFIG_PARTITION_UUIDS
 106                 info.uuid[0] = 0;
 107 #endif
 108         }
 109
 110         return fat_set_blk_dev(dev_desc, &info);
 111 }
 112
 113 /*
 114  * Get the first occurence of a directory delimiter ('/' or '\') in a string.
 115  * Return index into string if found, -1 otherwise.
 116  */
 117 static int dirdelim(char *str)
 118 {
 119         char *start = str;
 120
 121         while (*str != '\0') {
 122                 if (ISDIRDELIM(*str))
 123                         return str - start;
 124                 str++;
 125         }
 126         return -1;
 127 }
 128
 129 /*
 130  * Extract zero terminated short name from a directory entry.
 131  */
 132 static void get_name(dir_entry *dirent, char *s_name)
 133 {
 134         char *ptr;
 135
 136         memcpy(s_name, dirent->name, 8);
 137         s_name[8] = '\0';
 138         ptr = s_name;
 139         while (*ptr && *ptr != ' ')
 140                 ptr++;
 141         if (dirent->ext[0] && dirent->ext[0] != ' ') {
 142                 *ptr = '.';
 143                 ptr++;
 144                 memcpy(ptr, dirent->ext, 3);
 145                 ptr[3] = '\0';
 146                 while (*ptr && *ptr != ' ')
 147                         ptr++;
 148         }
 149         *ptr = '\0';
 150         if (*s_name == DELETED_FLAG)
 151                 *s_name = '\0';
 152         else if (*s_name == aRING)
 153                 *s_name = DELETED_FLAG;
 154         downcase(s_name);
 155 }
 156
 157 /*
 158  * Get the entry at index 'entry' in a FAT (12/16/32) table.
 159  * On failure 0x00 is returned.
 160  */
 161 static __u32 get_fatent(fsdata *mydata, __u32 entry)
 162 {
 163         __u32 bufnum;
 164         __u32 off16, offset;
 165         __u32 ret = 0x00;
 166         __u16 val1, val2;
 167
 168         switch (mydata->fatsize) {
 169         case 32:
 170                 bufnum = entry / FAT32BUFSIZE;
 171                 offset = entry - bufnum * FAT32BUFSIZE;
 172                 break;
 173         case 16:
 174                 bufnum = entry / FAT16BUFSIZE;
 175                 offset = entry - bufnum * FAT16BUFSIZE;
 176                 break;
 177         case 12:
 178                 bufnum = entry / FAT12BUFSIZE;
 179                 offset = entry - bufnum * FAT12BUFSIZE;
 180                 break;
 181
 182         default:
 183                 /* Unsupported FAT size */
 184                 return ret;
 185         }
 186
 187         debug("FAT%d: entry: 0x%04x = %d, offset: 0x%04x = %d\n",
 188                mydata->fatsize, entry, entry, offset, offset);
 189
 190         /* Read a new block of FAT entries into the cache. */
 191         if (bufnum != mydata->fatbufnum) {
 192                 __u32 getsize = FATBUFBLOCKS;
 193                 __u8 *bufptr = mydata->fatbuf;
 194                 __u32 fatlength = mydata->fatlength;
 195                 __u32 startblock = bufnum * FATBUFBLOCKS;
 196
 197                 if (startblock + getsize > fatlength)
 198                         getsize = fatlength - startblock;
 199
 200                 startblock += mydata->fat_sect; /* Offset from start of disk */
 201
 202                 if (disk_read(startblock, getsize, bufptr) < 0) {
 203                         debug("Error reading FAT blocks\n");
 204                         return ret;
 205                 }
 206                 mydata->fatbufnum = bufnum;
 207         }
 208
 209         /* Get the actual entry from the table */
 210         switch (mydata->fatsize) {
 211         case 32:
 212                 ret = FAT2CPU32(((__u32 *) mydata->fatbuf)[offset]);
 213                 break;
 214         case 16:
 215                 ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[offset]);
 216                 break;
 217         case 12:
 218                 off16 = (offset * 3) / 4;
 219
 220                 switch (offset & 0x3) {
 221                 case 0:
 222                         ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[off16]);
 223                         ret &= 0xfff;
 224                         break;
 225                 case 1:
 226                         val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 227                         val1 &= 0xf000;
 228                         val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
 229                         val2 &= 0x00ff;
 230                         ret = (val2 << 4) | (val1 >> 12);
 231                         break;
 232                 case 2:
 233                         val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 234                         val1 &= 0xff00;
 235                         val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
 236                         val2 &= 0x000f;
 237                         ret = (val2 << 8) | (val1 >> 8);
 238                         break;
 239                 case 3:
 240                         ret = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 241                         ret = (ret & 0xfff0) >> 4;
 242                         break;
 243                 default:
 244                         break;
 245                 }
 246                 break;
 247         }
 248         debug("FAT%d: ret: %08x, offset: %04x\n",
 249                mydata->fatsize, ret, offset);
 250
 251         return ret;
 252 }
 253
 254 /*
 255  * Read at most 'size' bytes from the specified cluster into 'buffer'.
 256  * Return 0 on success, -1 otherwise.
 257  */
 258 static int
 259 get_cluster(fsdata *mydata, __u32 clustnum, __u8 *buffer, unsigned long size)
 260 {
 261         __u32 idx = 0;
 262         __u32 startsect;
 263         int ret;
 264
 265         if (clustnum > 0) {
 266                 startsect = mydata->data_begin +
 267                                 clustnum * mydata->clust_size;
 268         } else {
 269                 startsect = mydata->rootdir_sect;
 270         }
 271
 272         debug("gc - clustnum: %d, startsect: %d\n", clustnum, startsect);
 273
 274         if ((unsigned long)buffer & (ARCH_DMA_MINALIGN - 1)) {
 275                 ALLOC_CACHE_ALIGN_BUFFER(__u8, tmpbuf, mydata->sect_size);
 276
 277                 printf("FAT: Misaligned buffer address (%p)\n", buffer);
 278
 279                 while (size >= mydata->sect_size) {
 280                         ret = disk_read(startsect++, 1, tmpbuf);
 281                         if (ret != 1) {
 282                                 debug("Error reading data (got %d)\n", ret);
 283                                 return -1;
 284                         }
 285
 286                         memcpy(buffer, tmpbuf, mydata->sect_size);
 287                         buffer += mydata->sect_size;
 288                         size -= mydata->sect_size;
 289                 }
 290         } else {
 291                 idx = size / mydata->sect_size;
 292                 ret = disk_read(startsect, idx, buffer);
 293                 if (ret != idx) {
 294                         debug("Error reading data (got %d)\n", ret);
 295                         return -1;
 296                 }
 297                 startsect += idx;
 298                 idx *= mydata->sect_size;
 299                 buffer += idx;
 300                 size -= idx;
 301         }
 302         if (size) {
 303                 ALLOC_CACHE_ALIGN_BUFFER(__u8, tmpbuf, mydata->sect_size);
 304
 305                 ret = disk_read(startsect, 1, tmpbuf);
 306                 if (ret != 1) {
 307                         debug("Error reading data (got %d)\n", ret);
 308                         return -1;
 309                 }
 310
 311                 memcpy(buffer, tmpbuf, size);
 312         }
 313
 314         return 0;
 315 }
 316
 317 /*
 318  * Read at most 'maxsize' bytes from 'pos' in the file associated with 'dentptr'
 319  * into 'buffer'.
 320  * Update the number of bytes read in *gotsize or return -1 on fatal errors.
 321  */
 322 __u8 get_contents_vfatname_block[MAX_CLUSTSIZE]
 323         __aligned(ARCH_DMA_MINALIGN);
 324
 325 static int get_contents(fsdata *mydata, dir_entry *dentptr, loff_t pos,
 326                         __u8 *buffer, loff_t maxsize, loff_t *gotsize)
 327 {
 328         loff_t filesize = FAT2CPU32(dentptr->size);
 329         unsigned int bytesperclust = mydata->clust_size * mydata->sect_size;
 330         __u32 curclust = START(dentptr);
 331         __u32 endclust, newclust;
 332         loff_t actsize;
 333
 334         *gotsize = 0;
 335         debug("Filesize: %llu bytes\n", filesize);
 336
 337         if (pos >= filesize) {
 338                 debug("Read position past EOF: %llu\n", pos);
 339                 return 0;
 340         }
 341
 342         if (maxsize > 0 && filesize > pos + maxsize)
 343                 filesize = pos + maxsize;
 344
 345         debug("%llu bytes\n", filesize);
 346
 347         actsize = bytesperclust;
 348
 349         /* go to cluster at pos */
 350         while (actsize <= pos) {
 351                 curclust = get_fatent(mydata, curclust);
 352                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 353                         debug("curclust: 0x%x\n", curclust);
 354                         debug("Invalid FAT entry\n");
 355                         return 0;
 356                 }
 357                 actsize += bytesperclust;
 358         }
 359
 360         /* actsize > pos */
 361         actsize -= bytesperclust;
 362         filesize -= actsize;
 363         pos -= actsize;
 364
 365         /* align to beginning of next cluster if any */
 366         if (pos) {
 367                 actsize = min(filesize, (loff_t)bytesperclust);
 368                 if (get_cluster(mydata, curclust, get_contents_vfatname_block,
 369                                 (int)actsize) != 0) {
 370                         printf("Error reading cluster\n");
 371                         return -1;
 372                 }
 373                 filesize -= actsize;
 374                 actsize -= pos;
 375                 memcpy(buffer, get_contents_vfatname_block + pos, actsize);
 376                 *gotsize += actsize;
 377                 if (!filesize)
 378                         return 0;
 379                 buffer += actsize;
 380
 381                 curclust = get_fatent(mydata, curclust);
 382                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 383                         debug("curclust: 0x%x\n", curclust);
 384                         debug("Invalid FAT entry\n");
 385                         return 0;
 386                 }
 387         }
 388
 389         actsize = bytesperclust;
 390         endclust = curclust;
 391
 392         do {
 393                 /* search for consecutive clusters */
 394                 while (actsize < filesize) {
 395                         newclust = get_fatent(mydata, endclust);
 396                         if ((newclust - 1) != endclust)
 397                                 goto getit;
 398                         if (CHECK_CLUST(newclust, mydata->fatsize)) {
 399                                 debug("curclust: 0x%x\n", newclust);
 400                                 debug("Invalid FAT entry\n");
 401                                 return 0;
 402                         }
 403                         endclust = newclust;
 404                         actsize += bytesperclust;
 405                 }
 406
 407                 /* get remaining bytes */
 408                 actsize = filesize;
 409                 if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
 410                         printf("Error reading cluster\n");
 411                         return -1;
 412                 }
 413                 *gotsize += actsize;
 414                 return 0;
 415 getit:
 416                 if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
 417                         printf("Error reading cluster\n");
 418                         return -1;
 419                 }
 420                 *gotsize += (int)actsize;
 421                 filesize -= actsize;
 422                 buffer += actsize;
 423
 424                 curclust = get_fatent(mydata, endclust);
 425                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 426                         debug("curclust: 0x%x\n", curclust);
 427                         printf("Invalid FAT entry\n");
 428                         return 0;
 429                 }
 430                 actsize = bytesperclust;
 431                 endclust = curclust;
 432         } while (1);
 433 }
 434
 435 /*
 436  * Extract the file name information from 'slotptr' into 'l_name',
 437  * starting at l_name[*idx].
 438  * Return 1 if terminator (zero byte) is found, 0 otherwise.
 439  */
 440 static int slot2str(dir_slot *slotptr, char *l_name, int *idx)
 441 {
 442         int j;
 443
 444         for (j = 0; j <= 8; j += 2) {
 445                 l_name[*idx] = slotptr->name0_4[j];
 446                 if (l_name[*idx] == 0x00)
 447                         return 1;
 448                 (*idx)++;
 449         }
 450         for (j = 0; j <= 10; j += 2) {
 451                 l_name[*idx] = slotptr->name5_10[j];
 452                 if (l_name[*idx] == 0x00)
 453                         return 1;
 454                 (*idx)++;
 455         }
 456         for (j = 0; j <= 2; j += 2) {
 457                 l_name[*idx] = slotptr->name11_12[j];
 458                 if (l_name[*idx] == 0x00)
 459                         return 1;
 460                 (*idx)++;
 461         }
 462
 463         return 0;
 464 }
 465
 466 /*
 467  * Extract the full long filename starting at 'retdent' (which is really
 468  * a slot) into 'l_name'. If successful also copy the real directory entry
 469  * into 'retdent'
 470  * Return 0 on success, -1 otherwise.
 471  */
 472 static int
 473 get_vfatname(fsdata *mydata, int curclust, __u8 *cluster,
 474              dir_entry *retdent, char *l_name)
 475 {
 476         dir_entry *realdent;
 477         dir_slot *slotptr = (dir_slot *)retdent;
 478         __u8 *buflimit = cluster + mydata->sect_size * ((curclust == 0) ?
 479                                                         PREFETCH_BLOCKS :
 480                                                         mydata->clust_size);
 481         __u8 counter = (slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff;
 482         int idx = 0;
 483
 484         if (counter > VFAT_MAXSEQ) {
 485                 debug("Error: VFAT name is too long\n");
 486                 return -1;
 487         }
 488
 489         while ((__u8 *)slotptr < buflimit) {
 490                 if (counter == 0)
 491                         break;
 492                 if (((slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff) != counter)
 493                         return -1;
 494                 slotptr++;
 495                 counter--;
 496         }
 497
 498         if ((__u8 *)slotptr >= buflimit) {
 499                 dir_slot *slotptr2;
 500
 501                 if (curclust == 0)
 502                         return -1;
 503                 curclust = get_fatent(mydata, curclust);
 504                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 505                         debug("curclust: 0x%x\n", curclust);
 506                         printf("Invalid FAT entry\n");
 507                         return -1;
 508                 }
 509
 510                 if (get_cluster(mydata, curclust, get_contents_vfatname_block,
 511                                 mydata->clust_size * mydata->sect_size) != 0) {
 512                         debug("Error: reading directory block\n");
 513                         return -1;
 514                 }
 515
 516                 slotptr2 = (dir_slot *)get_contents_vfatname_block;
 517                 while (counter > 0) {
 518                         if (((slotptr2->id & ~LAST_LONG_ENTRY_MASK)
 519                             & 0xff) != counter)
 520                                 return -1;
 521                         slotptr2++;
 522                         counter--;
 523                 }
 524
 525                 /* Save the real directory entry */
 526                 realdent = (dir_entry *)slotptr2;
 527                 while ((__u8 *)slotptr2 > get_contents_vfatname_block) {
 528                         slotptr2--;
 529                         slot2str(slotptr2, l_name, &idx);
 530                 }
 531         } else {
 532                 /* Save the real directory entry */
 533                 realdent = (dir_entry *)slotptr;
 534         }
 535
 536         do {
 537                 slotptr--;
 538                 if (slot2str(slotptr, l_name, &idx))
 539                         break;
 540         } while (!(slotptr->id & LAST_LONG_ENTRY_MASK));
 541
 542         l_name[idx] = '\0';
 543         if (*l_name == DELETED_FLAG)
 544                 *l_name = '\0';
 545         else if (*l_name == aRING)
 546                 *l_name = DELETED_FLAG;
 547         downcase(l_name);
 548
 549         /* Return the real directory entry */
 550         memcpy(retdent, realdent, sizeof(dir_entry));
 551
 552         return 0;
 553 }
 554
 555 /* Calculate short name checksum */
 556 static __u8 mkcksum(const char name[8], const char ext[3])
 557 {
 558         int i;
 559
 560         __u8 ret = 0;
 561
 562         for (i = 0; i < 8; i++)
 563                 ret = (((ret & 1) << 7) | ((ret & 0xfe) >> 1)) + name[i];
 564         for (i = 0; i < 3; i++)
 565                 ret = (((ret & 1) << 7) | ((ret & 0xfe) >> 1)) + ext[i];
 566
 567         return ret;
 568 }
 569
 570 /*
 571  * Get the directory entry associated with 'filename' from the directory
 572  * starting at 'startsect'
 573  */
 574 __u8 get_dentfromdir_block[MAX_CLUSTSIZE]
 575         __aligned(ARCH_DMA_MINALIGN);
 576
 577 static dir_entry *get_dentfromdir(fsdata *mydata, int startsect,
 578                                   char *filename, dir_entry *retdent,
 579                                   int dols)
 580 {
 581         __u16 prevcksum = 0xffff;
 582         __u32 curclust = START(retdent);
 583         int files = 0, dirs = 0;
 584
 585         debug("get_dentfromdir: %s\n", filename);
 586
 587         while (1) {
 588                 dir_entry *dentptr;
 589
 590                 int i;
 591
 592                 if (get_cluster(mydata, curclust, get_dentfromdir_block,
 593                                 mydata->clust_size * mydata->sect_size) != 0) {
 594                         debug("Error: reading directory block\n");
 595                         return NULL;
 596                 }
 597
 598                 dentptr = (dir_entry *)get_dentfromdir_block;
 599
 600                 for (i = 0; i < DIRENTSPERCLUST; i++) {
 601                         char s_name[14], l_name[VFAT_MAXLEN_BYTES];
 602
 603                         l_name[0] = '\0';
 604                         if (dentptr->name[0] == DELETED_FLAG) {
 605                                 dentptr++;
 606                                 continue;
 607                         }
 608                         if ((dentptr->attr & ATTR_VOLUME)) {
 609                                 if (vfat_enabled &&
 610                                     (dentptr->attr & ATTR_VFAT) == ATTR_VFAT &&
 611                                     (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
 612                                         prevcksum = ((dir_slot *)dentptr)->alias_checksum;
 613                                         get_vfatname(mydata, curclust,
 614                                                      get_dentfromdir_block,
 615                                                      dentptr, l_name);
 616                                         if (dols) {
 617                                                 int isdir;
 618                                                 char dirc;
 619                                                 int doit = 0;
 620
 621                                                 isdir = (dentptr->attr & ATTR_DIR);
 622
 623                                                 if (isdir) {
 624                                                         dirs++;
 625                                                         dirc = '/';
 626                                                         doit = 1;
 627                                                 } else {
 628                                                         dirc = ' ';
 629                                                         if (l_name[0] != 0) {
 630                                                                 files++;
 631                                                                 doit = 1;
 632                                                         }
 633                                                 }
 634                                                 if (doit) {
 635                                                         if (dirc == ' ') {
 636                                                                 printf(" %8u   %s%c\n",
 637                                                                        FAT2CPU32(dentptr->size),
 638                                                                         l_name,
 639                                                                         dirc);
 640                                                         } else {
 641                                                                 printf("            %s%c\n",
 642                                                                         l_name,
 643                                                                         dirc);
 644                                                         }
 645                                                 }
 646                                                 dentptr++;
 647                                                 continue;
 648                                         }
 649                                         debug("vfatname: |%s|\n", l_name);
 650                                 } else {
 651                                         /* Volume label or VFAT entry */
 652                                         dentptr++;
 653                                         continue;
 654                                 }
 655                         }
 656                         if (dentptr->name[0] == 0) {
 657                                 if (dols) {
 658                                         printf("\n%d file(s), %d dir(s)\n\n",
 659                                                 files, dirs);
 660                                 }
 661                                 debug("Dentname == NULL - %d\n", i);
 662                                 return NULL;
 663                         }
 664                         if (vfat_enabled) {
 665                                 __u8 csum = mkcksum(dentptr->name, dentptr->ext);
 666                                 if (dols && csum == prevcksum) {
 667                                         prevcksum = 0xffff;
 668                                         dentptr++;
 669                                         continue;
 670                                 }
 671                         }
 672
 673                         get_name(dentptr, s_name);
 674                         if (dols) {
 675                                 int isdir = (dentptr->attr & ATTR_DIR);
 676                                 char dirc;
 677                                 int doit = 0;
 678
 679                                 if (isdir) {
 680                                         dirs++;
 681                                         dirc = '/';
 682                                         doit = 1;
 683                                 } else {
 684                                         dirc = ' ';
 685                                         if (s_name[0] != 0) {
 686                                                 files++;
 687                                                 doit = 1;
 688                                         }
 689                                 }
 690
 691                                 if (doit) {
 692                                         if (dirc == ' ') {
 693                                                 printf(" %8u   %s%c\n",
 694                                                        FAT2CPU32(dentptr->size),
 695                                                         s_name, dirc);
 696                                         } else {
 697                                                 printf("            %s%c\n",
 698                                                         s_name, dirc);
 699                                         }
 700                                 }
 701
 702                                 dentptr++;
 703                                 continue;
 704                         }
 705
 706                         if (strcmp(filename, s_name)
 707                             && strcmp(filename, l_name)) {
 708                                 debug("Mismatch: |%s|%s|\n", s_name, l_name);
 709                                 dentptr++;
 710                                 continue;
 711                         }
 712
 713                         memcpy(retdent, dentptr, sizeof(dir_entry));
 714
 715                         debug("DentName: %s", s_name);
 716                         debug(", start: 0x%x", START(dentptr));
 717                         debug(", size:  0x%x %s\n",
 718                               FAT2CPU32(dentptr->size),
 719                               (dentptr->attr & ATTR_DIR) ? "(DIR)" : "");
 720
 721                         return retdent;
 722                 }
 723
 724                 curclust = get_fatent(mydata, curclust);
 725                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 726                         debug("curclust: 0x%x\n", curclust);
 727                         printf("Invalid FAT entry\n");
 728                         return NULL;
 729                 }
 730         }
 731
 732         return NULL;
 733 }
 734
 735 /*
 736  * Read boot sector and volume info from a FAT filesystem
 737  */
 738 static int
 739 read_bootsectandvi(boot_sector *bs, volume_info *volinfo, int *fatsize)
 740 {
 741         __u8 *block;
 742         volume_info *vistart;
 743         int ret = 0;
 744
 745         if (cur_dev == NULL) {
 746                 debug("Error: no device selected\n");
 747                 return -1;
 748         }
 749
 750         block = memalign(ARCH_DMA_MINALIGN, cur_dev->blksz);
 751         if (block == NULL) {
 752                 debug("Error: allocating block\n");
 753                 return -1;
 754         }
 755
 756         if (disk_read(0, 1, block) < 0) {
 757                 debug("Error: reading block\n");
 758                 goto fail;
 759         }
 760
 761         memcpy(bs, block, sizeof(boot_sector));
 762         bs->reserved = FAT2CPU16(bs->reserved);
 763         bs->fat_length = FAT2CPU16(bs->fat_length);
 764         bs->secs_track = FAT2CPU16(bs->secs_track);
 765         bs->heads = FAT2CPU16(bs->heads);
 766         bs->total_sect = FAT2CPU32(bs->total_sect);
 767
 768         /* FAT32 entries */
 769         if (bs->fat_length == 0) {
 770                 /* Assume FAT32 */
 771                 bs->fat32_length = FAT2CPU32(bs->fat32_length);
 772                 bs->flags = FAT2CPU16(bs->flags);
 773                 bs->root_cluster = FAT2CPU32(bs->root_cluster);
 774                 bs->info_sector = FAT2CPU16(bs->info_sector);
 775                 bs->backup_boot = FAT2CPU16(bs->backup_boot);
 776                 vistart = (volume_info *)(block + sizeof(boot_sector));
 777                 *fatsize = 32;
 778         } else {
 779                 vistart = (volume_info *)&(bs->fat32_length);
 780                 *fatsize = 0;
 781         }
 782         memcpy(volinfo, vistart, sizeof(volume_info));
 783
 784         if (*fatsize == 32) {
 785                 if (strncmp(FAT32_SIGN, vistart->fs_type, SIGNLEN) == 0)
 786                         goto exit;
 787         } else {
 788                 if (strncmp(FAT12_SIGN, vistart->fs_type, SIGNLEN) == 0) {
 789                         *fatsize = 12;
 790                         goto exit;
 791                 }
 792                 if (strncmp(FAT16_SIGN, vistart->fs_type, SIGNLEN) == 0) {
 793                         *fatsize = 16;
 794                         goto exit;
 795                 }
 796         }
 797
 798         debug("Error: broken fs_type sign\n");
 799 fail:
 800         ret = -1;
 801 exit:
 802         free(block);
 803         return ret;
 804 }
 805
 806 __u8 do_fat_read_at_block[MAX_CLUSTSIZE]
 807         __aligned(ARCH_DMA_MINALIGN);
 808
 809 int do_fat_read_at(const char *filename, loff_t pos, void *buffer,
 810                    loff_t maxsize, int dols, int dogetsize, loff_t *size)
 811 {
 812         char fnamecopy[2048];
 813         boot_sector bs;
 814         volume_info volinfo;
 815         fsdata datablock;
 816         fsdata *mydata = &datablock;
 817         dir_entry *dentptr = NULL;
 818         __u16 prevcksum = 0xffff;
 819         char *subname = "";
 820         __u32 cursect;
 821         int idx, isdir = 0;
 822         int files = 0, dirs = 0;
 823         int ret = -1;
 824         int firsttime;
 825         __u32 root_cluster = 0;
 826         __u32 read_blk;
 827         int rootdir_size = 0;
 828         int buffer_blk_cnt;
 829         int do_read;
 830         __u8 *dir_ptr;
 831
 832         if (read_bootsectandvi(&bs, &volinfo, &mydata->fatsize)) {
 833                 debug("Error: reading boot sector\n");
 834                 return -1;
 835         }
 836
 837         if (mydata->fatsize == 32) {
 838                 root_cluster = bs.root_cluster;
 839                 mydata->fatlength = bs.fat32_length;
 840         } else {
 841                 mydata->fatlength = bs.fat_length;
 842         }
 843
 844         mydata->fat_sect = bs.reserved;
 845
 846         cursect = mydata->rootdir_sect
 847                 = mydata->fat_sect + mydata->fatlength * bs.fats;
 848
 849         mydata->sect_size = (bs.sector_size[1] << 8) + bs.sector_size[0];
 850         mydata->clust_size = bs.cluster_size;
 851         if (mydata->sect_size != cur_part_info.blksz) {
 852                 printf("Error: FAT sector size mismatch (fs=%hu, dev=%lu)\n",
 853                                 mydata->sect_size, cur_part_info.blksz);
 854                 return -1;
 855         }
 856
 857         if (mydata->fatsize == 32) {
 858                 mydata->data_begin = mydata->rootdir_sect -
 859                                         (mydata->clust_size * 2);
 860         } else {
 861                 rootdir_size = ((bs.dir_entries[1]  * (int)256 +
 862                                  bs.dir_entries[0]) *
 863                                  sizeof(dir_entry)) /
 864                                  mydata->sect_size;
 865                 mydata->data_begin = mydata->rootdir_sect +
 866                                         rootdir_size -
 867                                         (mydata->clust_size * 2);
 868         }
 869
 870         mydata->fatbufnum = -1;
 871         mydata->fatbuf = memalign(ARCH_DMA_MINALIGN, FATBUFSIZE);
 872         if (mydata->fatbuf == NULL) {
 873                 debug("Error: allocating memory\n");
 874                 return -1;
 875         }
 876
 877         if (vfat_enabled)
 878                 debug("VFAT Support enabled\n");
 879
 880         debug("FAT%d, fat_sect: %d, fatlength: %d\n",
 881                mydata->fatsize, mydata->fat_sect, mydata->fatlength);
 882         debug("Rootdir begins at cluster: %d, sector: %d, offset: %x\n"
 883                "Data begins at: %d\n",
 884                root_cluster,
 885                mydata->rootdir_sect,
 886                mydata->rootdir_sect * mydata->sect_size, mydata->data_begin);
 887         debug("Sector size: %d, cluster size: %d\n", mydata->sect_size,
 888               mydata->clust_size);
 889
 890         /* "cwd" is always the root... */
 891         while (ISDIRDELIM(*filename))
 892                 filename++;
 893
 894         /* Make a copy of the filename and convert it to lowercase */
 895         strcpy(fnamecopy, filename);
 896         downcase(fnamecopy);
 897
 898         if (*fnamecopy == '\0') {
 899                 if (!dols)
 900                         goto exit;
 901
 902                 dols = LS_ROOT;
 903         } else if ((idx = dirdelim(fnamecopy)) >= 0) {
 904                 isdir = 1;
 905                 fnamecopy[idx] = '\0';
 906                 subname = fnamecopy + idx + 1;
 907
 908                 /* Handle multiple delimiters */
 909                 while (ISDIRDELIM(*subname))
 910                         subname++;
 911         } else if (dols) {
 912                 isdir = 1;
 913         }
 914
 915         buffer_blk_cnt = 0;
 916         firsttime = 1;
 917         while (1) {
 918                 int i;
 919
 920                 if (mydata->fatsize == 32 || firsttime) {
 921                         dir_ptr = do_fat_read_at_block;
 922                         firsttime = 0;
 923                 } else {
 924                         /**
 925                          * FAT16 sector buffer modification:
 926                          * Each loop, the second buffered block is moved to
 927                          * the buffer begin, and two next sectors are read
 928                          * next to the previously moved one. So the sector
 929                          * buffer keeps always 3 sectors for fat16.
 930                          * And the current sector is the buffer second sector
 931                          * beside the "firsttime" read, when it is the first one.
 932                          *
 933                          * PREFETCH_BLOCKS is 2 for FAT16 == loop[0:1]
 934                          * n = computed root dir sector
 935                          * loop |  cursect-1  | cursect    | cursect+1  |
 936                          *   0  |  sector n+0 | sector n+1 | none       |
 937                          *   1  |  none       | sector n+0 | sector n+1 |
 938                          *   0  |  sector n+1 | sector n+2 | sector n+3 |
 939                          *   1  |  sector n+3 | ...
 940                         */
 941                         dir_ptr = (do_fat_read_at_block + mydata->sect_size);
 942                         memcpy(do_fat_read_at_block, dir_ptr, mydata->sect_size);
 943                 }
 944
 945                 do_read = 1;
 946
 947                 if (mydata->fatsize == 32 && buffer_blk_cnt)
 948                         do_read = 0;
 949
 950                 if (do_read) {
 951                         read_blk = (mydata->fatsize == 32) ?
 952                                     mydata->clust_size : PREFETCH_BLOCKS;
 953
 954                         debug("FAT read(sect=%d, cnt:%d), clust_size=%d, DIRENTSPERBLOCK=%zd\n",
 955                                 cursect, read_blk, mydata->clust_size, DIRENTSPERBLOCK);
 956
 957                         if (disk_read(cursect, read_blk, dir_ptr) < 0) {
 958                                 debug("Error: reading rootdir block\n");
 959                                 goto exit;
 960                         }
 961
 962                         dentptr = (dir_entry *)dir_ptr;
 963                 }
 964
 965                 for (i = 0; i < DIRENTSPERBLOCK; i++) {
 966                         char s_name[14], l_name[VFAT_MAXLEN_BYTES];
 967                         __u8 csum;
 968
 969                         l_name[0] = '\0';
 970                         if (dentptr->name[0] == DELETED_FLAG) {
 971                                 dentptr++;
 972                                 continue;
 973                         }
 974
 975                         if (vfat_enabled)
 976                                 csum = mkcksum(dentptr->name, dentptr->ext);
 977
 978                         if (dentptr->attr & ATTR_VOLUME) {
 979                                 if (vfat_enabled &&
 980                                     (dentptr->attr & ATTR_VFAT) == ATTR_VFAT &&
 981                                     (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
 982                                         prevcksum =
 983                                                 ((dir_slot *)dentptr)->alias_checksum;
 984
 985                                         get_vfatname(mydata,
 986                                                      root_cluster,
 987                                                      dir_ptr,
 988                                                      dentptr, l_name);
 989
 990                                         if (dols == LS_ROOT) {
 991                                                 char dirc;
 992                                                 int doit = 0;
 993                                                 int isdir =
 994                                                         (dentptr->attr & ATTR_DIR);
 995
 996                                                 if (isdir) {
 997                                                         dirs++;
 998                                                         dirc = '/';
 999                                                         doit = 1;
1000                                                 } else {
1001                                                         dirc = ' ';
1002                                                         if (l_name[0] != 0) {
1003                                                                 files++;
1004                                                                 doit = 1;
1005                                                         }
1006                                                 }
1007                                                 if (doit) {
1008                                                         if (dirc == ' ') {
1009                                                                 printf(" %8u   %s%c\n",
1010                                                                        FAT2CPU32(dentptr->size),
1011                                                                         l_name,
1012                                                                         dirc);
1013                                                         } else {
1014                                                                 printf("            %s%c\n",
1015                                                                         l_name,
1016                                                                         dirc);
1017                                                         }
1018                                                 }
1019                                                 dentptr++;
1020                                                 continue;
1021                                         }
1022                                         debug("Rootvfatname: |%s|\n",
1023                                                l_name);
1024                                 } else {
1025                                         /* Volume label or VFAT entry */
1026                                         dentptr++;
1027                                         continue;
1028                                 }
1029                         } else if (dentptr->name[0] == 0) {
1030                                 debug("RootDentname == NULL - %d\n", i);
1031                                 if (dols == LS_ROOT) {
1032                                         printf("\n%d file(s), %d dir(s)\n\n",
1033                                                 files, dirs);
1034                                         ret = 0;
1035                                 }
1036                                 goto exit;
1037                         }
1038                         else if (vfat_enabled &&
1039                                  dols == LS_ROOT && csum == prevcksum) {
1040                                 prevcksum = 0xffff;
1041                                 dentptr++;
1042                                 continue;
1043                         }
1044
1045                         get_name(dentptr, s_name);
1046
1047                         if (dols == LS_ROOT) {
1048                                 int isdir = (dentptr->attr & ATTR_DIR);
1049                                 char dirc;
1050                                 int doit = 0;
1051
1052                                 if (isdir) {
1053                                         dirc = '/';
1054                                         if (s_name[0] != 0) {
1055                                                 dirs++;
1056                                                 doit = 1;
1057                                         }
1058                                 } else {
1059                                         dirc = ' ';
1060                                         if (s_name[0] != 0) {
1061                                                 files++;
1062                                                 doit = 1;
1063                                         }
1064                                 }
1065                                 if (doit) {
1066                                         if (dirc == ' ') {
1067                                                 printf(" %8u   %s%c\n",
1068                                                        FAT2CPU32(dentptr->size),
1069                                                         s_name, dirc);
1070                                         } else {
1071                                                 printf("            %s%c\n",
1072                                                         s_name, dirc);
1073                                         }
1074                                 }
1075                                 dentptr++;
1076                                 continue;
1077                         }
1078
1079                         if (strcmp(fnamecopy, s_name)
1080                             && strcmp(fnamecopy, l_name)) {
1081                                 debug("RootMismatch: |%s|%s|\n", s_name,
1082                                        l_name);
1083                                 dentptr++;
1084                                 continue;
1085                         }
1086
1087                         if (isdir && !(dentptr->attr & ATTR_DIR))
1088                                 goto exit;
1089
1090                         debug("RootName: %s", s_name);
1091                         debug(", start: 0x%x", START(dentptr));
1092                         debug(", size:  0x%x %s\n",
1093                                FAT2CPU32(dentptr->size),
1094                                isdir ? "(DIR)" : "");
1095
1096                         goto rootdir_done;      /* We got a match */
1097                 }
1098                 debug("END LOOP: buffer_blk_cnt=%d   clust_size=%d\n", buffer_blk_cnt,
1099                        mydata->clust_size);
1100
1101                 /*
1102                  * On FAT32 we must fetch the FAT entries for the next
1103                  * root directory clusters when a cluster has been
1104                  * completely processed.
1105                  */
1106                 ++buffer_blk_cnt;
1107                 int rootdir_end = 0;
1108                 if (mydata->fatsize == 32) {
1109                         if (buffer_blk_cnt == mydata->clust_size) {
1110                                 int nxtsect = 0;
1111                                 int nxt_clust = 0;
1112
1113                                 nxt_clust = get_fatent(mydata, root_cluster);
1114                                 rootdir_end = CHECK_CLUST(nxt_clust, 32);
1115
1116                                 nxtsect = mydata->data_begin +
1117                                         (nxt_clust * mydata->clust_size);
1118
1119                                 root_cluster = nxt_clust;
1120
1121                                 cursect = nxtsect;
1122                                 buffer_blk_cnt = 0;
1123                         }
1124                 } else {
1125                         if (buffer_blk_cnt == PREFETCH_BLOCKS)
1126                                 buffer_blk_cnt = 0;
1127
1128                         rootdir_end = (++cursect - mydata->rootdir_sect >=
1129                                        rootdir_size);
1130                 }
1131
1132                 /* If end of rootdir reached */
1133                 if (rootdir_end) {
1134                         if (dols == LS_ROOT) {
1135                                 printf("\n%d file(s), %d dir(s)\n\n",
1136                                        files, dirs);
1137                                 *size = 0;
1138                         }
1139                         goto exit;
1140                 }
1141         }
1142 rootdir_done:
1143
1144         firsttime = 1;
1145
1146         while (isdir) {
1147                 int startsect = mydata->data_begin
1148                         + START(dentptr) * mydata->clust_size;
1149                 dir_entry dent;
1150                 char *nextname = NULL;
1151
1152                 dent = *dentptr;
1153                 dentptr = &dent;
1154
1155                 idx = dirdelim(subname);
1156
1157                 if (idx >= 0) {
1158                         subname[idx] = '\0';
1159                         nextname = subname + idx + 1;
1160                         /* Handle multiple delimiters */
1161                         while (ISDIRDELIM(*nextname))
1162                                 nextname++;
1163                         if (dols && *nextname == '\0')
1164                                 firsttime = 0;
1165                 } else {
1166                         if (dols && firsttime) {
1167                                 firsttime = 0;
1168                         } else {
1169                                 isdir = 0;
1170                         }
1171                 }
1172
1173                 if (get_dentfromdir(mydata, startsect, subname, dentptr,
1174                                      isdir ? 0 : dols) == NULL) {
1175                         if (dols && !isdir)
1176                                 *size = 0;
1177                         goto exit;
1178                 }
1179
1180                 if (isdir && !(dentptr->attr & ATTR_DIR))
1181                         goto exit;
1182
1183                 if (idx >= 0)
1184                         subname = nextname;
1185         }
1186
1187         if (dogetsize) {
1188                 *size = FAT2CPU32(dentptr->size);
1189                 ret = 0;
1190         } else {
1191                 ret = get_contents(mydata, dentptr, pos, buffer, maxsize, size);
1192         }
1193         debug("Size: %u, got: %llu\n", FAT2CPU32(dentptr->size), *size);
1194
1195 exit:
1196         free(mydata->fatbuf);
1197         return ret;
1198 }
1199
1200 int do_fat_read(const char *filename, void *buffer, loff_t maxsize, int dols,
1201                 loff_t *actread)
1202 {
1203         return do_fat_read_at(filename, 0, buffer, maxsize, dols, 0, actread);
1204 }
1205
1206 int file_fat_detectfs(void)
1207 {
1208         boot_sector bs;
1209         volume_info volinfo;
1210         int fatsize;
1211         char vol_label[12];
1212
1213         if (cur_dev == NULL) {
1214                 printf("No current device\n");
1215                 return 1;
1216         }
1217
1218 #if defined(CONFIG_CMD_IDE) || \
1219     defined(CONFIG_CMD_SATA) || \
1220     defined(CONFIG_CMD_SCSI) || \
1221     defined(CONFIG_CMD_USB) || \
1222     defined(CONFIG_MMC)
1223         printf("Interface:  ");
1224         switch (cur_dev->if_type) {
1225         case IF_TYPE_IDE:
1226                 printf("IDE");
1227                 break;
1228         case IF_TYPE_SATA:
1229                 printf("SATA");
1230                 break;
1231         case IF_TYPE_SCSI:
1232                 printf("SCSI");
1233                 break;
1234         case IF_TYPE_ATAPI:
1235                 printf("ATAPI");
1236                 break;
1237         case IF_TYPE_USB:
1238                 printf("USB");
1239                 break;
1240         case IF_TYPE_DOC:
1241                 printf("DOC");
1242                 break;
1243         case IF_TYPE_MMC:
1244                 printf("MMC");
1245                 break;
1246         default:
1247                 printf("Unknown");
1248         }
1249
1250         printf("\n  Device %d: ", cur_dev->dev);
1251         dev_print(cur_dev);
1252 #endif
1253
1254         if (read_bootsectandvi(&bs, &volinfo, &fatsize)) {
1255                 printf("\nNo valid FAT fs found\n");
1256                 return 1;
1257         }
1258
1259         memcpy(vol_label, volinfo.volume_label, 11);
1260         vol_label[11] = '\0';
1261         volinfo.fs_type[5] = '\0';
1262
1263         printf("Filesystem: %s \"%s\"\n", volinfo.fs_type, vol_label);
1264
1265         return 0;
1266 }
1267
1268 int file_fat_ls(const char *dir)
1269 {
1270         loff_t size;
1271
1272         return do_fat_read(dir, NULL, 0, LS_YES, &size);
1273 }
1274
1275 int fat_exists(const char *filename)
1276 {
1277         int ret;
1278         loff_t size;
1279
1280         ret = do_fat_read_at(filename, 0, NULL, 0, LS_NO, 1, &size);
1281         return ret == 0;
1282 }
1283
1284 int fat_size(const char *filename, loff_t *size)
1285 {
1286         return do_fat_read_at(filename, 0, NULL, 0, LS_NO, 1, size);
1287 }
1288
1289 int file_fat_read_at(const char *filename, loff_t pos, void *buffer,
1290                      loff_t maxsize, loff_t *actread)
1291 {
1292         printf("reading %s\n", filename);
1293         return do_fat_read_at(filename, pos, buffer, maxsize, LS_NO, 0,
1294                               actread);
1295 }
1296
1297 int file_fat_read(const char *filename, void *buffer, int maxsize)
1298 {
1299         loff_t actread;
1300         int ret;
1301
1302         ret =  file_fat_read_at(filename, 0, buffer, maxsize, &actread);
1303         if (ret)
1304                 return ret;
1305         else
1306                 return actread;
1307 }
1308
1309 int fat_read_file(const char *filename, void *buf, loff_t offset, loff_t len,
1310                   loff_t *actread)
1311 {
1312         int ret;
1313
1314         ret = file_fat_read_at(filename, offset, buf, len, actread);
1315         if (ret)
1316                 printf("** Unable to read file %s **\n", filename);
1317
1318         return ret;
1319 }
1320
1321 void fat_close(void)
1322 {
1323 }