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  * See file CREDITS for list of people who contributed to this
  10  * project.
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License as
  14  * published by the Free Software Foundation; either version 2 of
  15  * the License, or (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  25  * MA 02111-1307 USA
  26  */
  27
  28 #include <common.h>
  29 #include <config.h>
  30 #include <fat.h>
  31 #include <asm/byteorder.h>
  32 #include <part.h>
  33
  34 /*
  35  * Convert a string to lowercase.
  36  */
  37 static void downcase (char *str)
  38 {
  39         while (*str != '\0') {
  40                 TOLOWER(*str);
  41                 str++;
  42         }
  43 }
  44
  45 static block_dev_desc_t *cur_dev = NULL;
  46
  47 static unsigned long part_offset = 0;
  48
  49 static int cur_part = 1;
  50
  51 #define DOS_PART_TBL_OFFSET     0x1be
  52 #define DOS_PART_MAGIC_OFFSET   0x1fe
  53 #define DOS_FS_TYPE_OFFSET      0x36
  54 #define DOS_FS32_TYPE_OFFSET    0x52
  55
  56 static int disk_read (__u32 startblock, __u32 getsize, __u8 * bufptr)
  57 {
  58         if (cur_dev == NULL)
  59                 return -1;
  60
  61         startblock += part_offset;
  62
  63         if (cur_dev->block_read) {
  64                 return cur_dev->block_read(cur_dev->dev, startblock, getsize,
  65                                            (unsigned long *) bufptr);
  66         }
  67         return -1;
  68 }
  69
  70 int fat_register_device (block_dev_desc_t * dev_desc, int part_no)
  71 {
  72         unsigned char buffer[SECTOR_SIZE];
  73
  74         disk_partition_t info;
  75
  76         if (!dev_desc->block_read)
  77                 return -1;
  78
  79         cur_dev = dev_desc;
  80         /* check if we have a MBR (on floppies we have only a PBR) */
  81         if (dev_desc->block_read(dev_desc->dev, 0, 1, (ulong *)buffer) != 1) {
  82                 printf("** Can't read from device %d **\n",
  83                         dev_desc->dev);
  84                 return -1;
  85         }
  86         if (buffer[DOS_PART_MAGIC_OFFSET] != 0x55 ||
  87             buffer[DOS_PART_MAGIC_OFFSET + 1] != 0xaa) {
  88                 /* no signature found */
  89                 return -1;
  90         }
  91 #if (defined(CONFIG_CMD_IDE) || \
  92      defined(CONFIG_CMD_MG_DISK) || \
  93      defined(CONFIG_CMD_SATA) || \
  94      defined(CONFIG_CMD_SCSI) || \
  95      defined(CONFIG_CMD_USB) || \
  96      defined(CONFIG_MMC) || \
  97      defined(CONFIG_SYSTEMACE) )
  98         /* First we assume there is a MBR */
  99         if (!get_partition_info(dev_desc, part_no, &info)) {
 100                 part_offset = info.start;
 101                 cur_part = part_no;
 102         } else if ((strncmp((char *)&buffer[DOS_FS_TYPE_OFFSET], "FAT", 3) == 0) ||
 103                    (strncmp((char *)&buffer[DOS_FS32_TYPE_OFFSET], "FAT32", 5) == 0)) {
 104                 /* ok, we assume we are on a PBR only */
 105                 cur_part = 1;
 106                 part_offset = 0;
 107         } else {
 108                 printf("** Partition %d not valid on device %d **\n",
 109                         part_no, dev_desc->dev);
 110                 return -1;
 111         }
 112
 113 #else
 114         if ((strncmp((char *)&buffer[DOS_FS_TYPE_OFFSET], "FAT", 3) == 0) ||
 115             (strncmp((char *)&buffer[DOS_FS32_TYPE_OFFSET], "FAT32", 5) == 0)) {
 116                 /* ok, we assume we are on a PBR only */
 117                 cur_part = 1;
 118                 part_offset = 0;
 119                 info.start = part_offset;
 120         } else {
 121                 /* FIXME we need to determine the start block of the
 122                  * partition where the DOS FS resides. This can be done
 123                  * by using the get_partition_info routine. For this
 124                  * purpose the libpart must be included.
 125                  */
 126                 part_offset = 32;
 127                 cur_part = 1;
 128         }
 129 #endif
 130         return 0;
 131 }
 132
 133 /*
 134  * Get the first occurence of a directory delimiter ('/' or '\') in a string.
 135  * Return index into string if found, -1 otherwise.
 136  */
 137 static int dirdelim (char *str)
 138 {
 139         char *start = str;
 140
 141         while (*str != '\0') {
 142                 if (ISDIRDELIM(*str))
 143                         return str - start;
 144                 str++;
 145         }
 146         return -1;
 147 }
 148
 149 /*
 150  * Extract zero terminated short name from a directory entry.
 151  */
 152 static void get_name (dir_entry *dirent, char *s_name)
 153 {
 154         char *ptr;
 155
 156         memcpy(s_name, dirent->name, 8);
 157         s_name[8] = '\0';
 158         ptr = s_name;
 159         while (*ptr && *ptr != ' ')
 160                 ptr++;
 161         if (dirent->ext[0] && dirent->ext[0] != ' ') {
 162                 *ptr = '.';
 163                 ptr++;
 164                 memcpy(ptr, dirent->ext, 3);
 165                 ptr[3] = '\0';
 166                 while (*ptr && *ptr != ' ')
 167                         ptr++;
 168         }
 169         *ptr = '\0';
 170         if (*s_name == DELETED_FLAG)
 171                 *s_name = '\0';
 172         else if (*s_name == aRING)
 173                 *s_name = DELETED_FLAG;
 174         downcase(s_name);
 175 }
 176
 177 /*
 178  * Get the entry at index 'entry' in a FAT (12/16/32) table.
 179  * On failure 0x00 is returned.
 180  */
 181 static __u32 get_fatent (fsdata *mydata, __u32 entry)
 182 {
 183         __u32 bufnum;
 184         __u32 off16, offset;
 185         __u32 ret = 0x00;
 186         __u16 val1, val2;
 187
 188         switch (mydata->fatsize) {
 189         case 32:
 190                 bufnum = entry / FAT32BUFSIZE;
 191                 offset = entry - bufnum * FAT32BUFSIZE;
 192                 break;
 193         case 16:
 194                 bufnum = entry / FAT16BUFSIZE;
 195                 offset = entry - bufnum * FAT16BUFSIZE;
 196                 break;
 197         case 12:
 198                 bufnum = entry / FAT12BUFSIZE;
 199                 offset = entry - bufnum * FAT12BUFSIZE;
 200                 break;
 201
 202         default:
 203                 /* Unsupported FAT size */
 204                 return ret;
 205         }
 206
 207         debug("FAT%d: entry: 0x%04x = %d, offset: 0x%04x = %d\n",
 208                mydata->fatsize, entry, entry, offset, offset);
 209
 210         /* Read a new block of FAT entries into the cache. */
 211         if (bufnum != mydata->fatbufnum) {
 212                 int getsize = FATBUFSIZE / FS_BLOCK_SIZE;
 213                 __u8 *bufptr = mydata->fatbuf;
 214                 __u32 fatlength = mydata->fatlength;
 215                 __u32 startblock = bufnum * FATBUFBLOCKS;
 216
 217                 fatlength *= SECTOR_SIZE;       /* We want it in bytes now */
 218                 startblock += mydata->fat_sect; /* Offset from start of disk */
 219
 220                 if (getsize > fatlength)
 221                         getsize = fatlength;
 222                 if (disk_read(startblock, getsize, bufptr) < 0) {
 223                         debug("Error reading FAT blocks\n");
 224                         return ret;
 225                 }
 226                 mydata->fatbufnum = bufnum;
 227         }
 228
 229         /* Get the actual entry from the table */
 230         switch (mydata->fatsize) {
 231         case 32:
 232                 ret = FAT2CPU32(((__u32 *) mydata->fatbuf)[offset]);
 233                 break;
 234         case 16:
 235                 ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[offset]);
 236                 break;
 237         case 12:
 238                 off16 = (offset * 3) / 4;
 239
 240                 switch (offset & 0x3) {
 241                 case 0:
 242                         ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[off16]);
 243                         ret &= 0xfff;
 244                         break;
 245                 case 1:
 246                         val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 247                         val1 &= 0xf000;
 248                         val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
 249                         val2 &= 0x00ff;
 250                         ret = (val2 << 4) | (val1 >> 12);
 251                         break;
 252                 case 2:
 253                         val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 254                         val1 &= 0xff00;
 255                         val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
 256                         val2 &= 0x000f;
 257                         ret = (val2 << 8) | (val1 >> 8);
 258                         break;
 259                 case 3:
 260                         ret = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 261                         ret = (ret & 0xfff0) >> 4;
 262                         break;
 263                 default:
 264                         break;
 265                 }
 266                 break;
 267         }
 268         debug("FAT%d: ret: %08x, offset: %04x\n",
 269                mydata->fatsize, ret, offset);
 270
 271         return ret;
 272 }
 273
 274 /*
 275  * Read at most 'size' bytes from the specified cluster into 'buffer'.
 276  * Return 0 on success, -1 otherwise.
 277  */
 278 static int
 279 get_cluster (fsdata *mydata, __u32 clustnum, __u8 *buffer,
 280              unsigned long size)
 281 {
 282         int idx = 0;
 283         __u32 startsect;
 284
 285         if (clustnum > 0) {
 286                 startsect = mydata->data_begin +
 287                                 clustnum * mydata->clust_size;
 288         } else {
 289                 startsect = mydata->rootdir_sect;
 290         }
 291
 292         debug("gc - clustnum: %d, startsect: %d\n", clustnum, startsect);
 293
 294         if (disk_read(startsect, size / FS_BLOCK_SIZE, buffer) < 0) {
 295                 debug("Error reading data\n");
 296                 return -1;
 297         }
 298         if (size % FS_BLOCK_SIZE) {
 299                 __u8 tmpbuf[FS_BLOCK_SIZE];
 300
 301                 idx = size / FS_BLOCK_SIZE;
 302                 if (disk_read(startsect + idx, 1, tmpbuf) < 0) {
 303                         debug("Error reading data\n");
 304                         return -1;
 305                 }
 306                 buffer += idx * FS_BLOCK_SIZE;
 307
 308                 memcpy(buffer, tmpbuf, size % FS_BLOCK_SIZE);
 309                 return 0;
 310         }
 311
 312         return 0;
 313 }
 314
 315 /*
 316  * Read at most 'maxsize' bytes from the file associated with 'dentptr'
 317  * into 'buffer'.
 318  * Return the number of bytes read or -1 on fatal errors.
 319  */
 320 static long
 321 get_contents (fsdata *mydata, dir_entry *dentptr, __u8 *buffer,
 322               unsigned long maxsize)
 323 {
 324         unsigned long filesize = FAT2CPU32(dentptr->size), gotsize = 0;
 325         unsigned int bytesperclust = mydata->clust_size * SECTOR_SIZE;
 326         __u32 curclust = START(dentptr);
 327         __u32 endclust, newclust;
 328         unsigned long actsize;
 329
 330         debug("Filesize: %ld bytes\n", filesize);
 331
 332         if (maxsize > 0 && filesize > maxsize)
 333                 filesize = maxsize;
 334
 335         debug("%ld bytes\n", filesize);
 336
 337         actsize = bytesperclust;
 338         endclust = curclust;
 339
 340         do {
 341                 /* search for consecutive clusters */
 342                 while (actsize < filesize) {
 343                         newclust = get_fatent(mydata, endclust);
 344                         if ((newclust - 1) != endclust)
 345                                 goto getit;
 346                         if (CHECK_CLUST(newclust, mydata->fatsize)) {
 347                                 debug("curclust: 0x%x\n", newclust);
 348                                 debug("Invalid FAT entry\n");
 349                                 return gotsize;
 350                         }
 351                         endclust = newclust;
 352                         actsize += bytesperclust;
 353                 }
 354
 355                 /* actsize >= file size */
 356                 actsize -= bytesperclust;
 357
 358                 /* get remaining clusters */
 359                 if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
 360                         printf("Error reading cluster\n");
 361                         return -1;
 362                 }
 363
 364                 /* get remaining bytes */
 365                 gotsize += (int)actsize;
 366                 filesize -= actsize;
 367                 buffer += actsize;
 368                 actsize = filesize;
 369                 if (get_cluster(mydata, endclust, buffer, (int)actsize) != 0) {
 370                         printf("Error reading cluster\n");
 371                         return -1;
 372                 }
 373                 gotsize += actsize;
 374                 return gotsize;
 375 getit:
 376                 if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
 377                         printf("Error reading cluster\n");
 378                         return -1;
 379                 }
 380                 gotsize += (int)actsize;
 381                 filesize -= actsize;
 382                 buffer += actsize;
 383
 384                 curclust = get_fatent(mydata, endclust);
 385                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 386                         debug("curclust: 0x%x\n", curclust);
 387                         printf("Invalid FAT entry\n");
 388                         return gotsize;
 389                 }
 390                 actsize = bytesperclust;
 391                 endclust = curclust;
 392         } while (1);
 393 }
 394
 395 #ifdef CONFIG_SUPPORT_VFAT
 396 /*
 397  * Extract the file name information from 'slotptr' into 'l_name',
 398  * starting at l_name[*idx].
 399  * Return 1 if terminator (zero byte) is found, 0 otherwise.
 400  */
 401 static int slot2str (dir_slot *slotptr, char *l_name, int *idx)
 402 {
 403         int j;
 404
 405         for (j = 0; j <= 8; j += 2) {
 406                 l_name[*idx] = slotptr->name0_4[j];
 407                 if (l_name[*idx] == 0x00)
 408                         return 1;
 409                 (*idx)++;
 410         }
 411         for (j = 0; j <= 10; j += 2) {
 412                 l_name[*idx] = slotptr->name5_10[j];
 413                 if (l_name[*idx] == 0x00)
 414                         return 1;
 415                 (*idx)++;
 416         }
 417         for (j = 0; j <= 2; j += 2) {
 418                 l_name[*idx] = slotptr->name11_12[j];
 419                 if (l_name[*idx] == 0x00)
 420                         return 1;
 421                 (*idx)++;
 422         }
 423
 424         return 0;
 425 }
 426
 427 /*
 428  * Extract the full long filename starting at 'retdent' (which is really
 429  * a slot) into 'l_name'. If successful also copy the real directory entry
 430  * into 'retdent'
 431  * Return 0 on success, -1 otherwise.
 432  */
 433 __attribute__ ((__aligned__ (__alignof__ (dir_entry))))
 434 __u8 get_vfatname_block[MAX_CLUSTSIZE];
 435
 436 static int
 437 get_vfatname (fsdata *mydata, int curclust, __u8 *cluster,
 438               dir_entry *retdent, char *l_name)
 439 {
 440         dir_entry *realdent;
 441         dir_slot *slotptr = (dir_slot *)retdent;
 442         __u8 *buflimit = cluster + ((curclust == 0) ?
 443                                         LINEAR_PREFETCH_SIZE :
 444                                         (mydata->clust_size * SECTOR_SIZE)
 445                                    );
 446         __u8 counter = (slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff;
 447         int idx = 0;
 448
 449         if (counter > VFAT_MAXSEQ) {
 450                 debug("Error: VFAT name is too long\n");
 451                 return -1;
 452         }
 453
 454         while ((__u8 *)slotptr < buflimit) {
 455                 if (counter == 0)
 456                         break;
 457                 if (((slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff) != counter)
 458                         return -1;
 459                 slotptr++;
 460                 counter--;
 461         }
 462
 463         if ((__u8 *)slotptr >= buflimit) {
 464                 dir_slot *slotptr2;
 465
 466                 if (curclust == 0)
 467                         return -1;
 468                 curclust = get_fatent(mydata, curclust);
 469                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 470                         debug("curclust: 0x%x\n", curclust);
 471                         printf("Invalid FAT entry\n");
 472                         return -1;
 473                 }
 474
 475                 if (get_cluster(mydata, curclust, get_vfatname_block,
 476                                 mydata->clust_size * SECTOR_SIZE) != 0) {
 477                         debug("Error: reading directory block\n");
 478                         return -1;
 479                 }
 480
 481                 slotptr2 = (dir_slot *)get_vfatname_block;
 482                 while (counter > 0) {
 483                         if (((slotptr2->id & ~LAST_LONG_ENTRY_MASK)
 484                             & 0xff) != counter)
 485                                 return -1;
 486                         slotptr2++;
 487                         counter--;
 488                 }
 489
 490                 /* Save the real directory entry */
 491                 realdent = (dir_entry *)slotptr2;
 492                 while ((__u8 *)slotptr2 > get_vfatname_block) {
 493                         slotptr2--;
 494                         slot2str(slotptr2, l_name, &idx);
 495                 }
 496         } else {
 497                 /* Save the real directory entry */
 498                 realdent = (dir_entry *)slotptr;
 499         }
 500
 501         do {
 502                 slotptr--;
 503                 if (slot2str(slotptr, l_name, &idx))
 504                         break;
 505         } while (!(slotptr->id & LAST_LONG_ENTRY_MASK));
 506
 507         l_name[idx] = '\0';
 508         if (*l_name == DELETED_FLAG)
 509                 *l_name = '\0';
 510         else if (*l_name == aRING)
 511                 *l_name = DELETED_FLAG;
 512         downcase(l_name);
 513
 514         /* Return the real directory entry */
 515         memcpy(retdent, realdent, sizeof(dir_entry));
 516
 517         return 0;
 518 }
 519
 520 /* Calculate short name checksum */
 521 static __u8 mkcksum (const char *str)
 522 {
 523         int i;
 524
 525         __u8 ret = 0;
 526
 527         for (i = 0; i < 11; i++) {
 528                 ret = (((ret & 1) << 7) | ((ret & 0xfe) >> 1)) + str[i];
 529         }
 530
 531         return ret;
 532 }
 533 #endif  /* CONFIG_SUPPORT_VFAT */
 534
 535 /*
 536  * Get the directory entry associated with 'filename' from the directory
 537  * starting at 'startsect'
 538  */
 539 __attribute__ ((__aligned__ (__alignof__ (dir_entry))))
 540 __u8 get_dentfromdir_block[MAX_CLUSTSIZE];
 541
 542 static dir_entry *get_dentfromdir (fsdata *mydata, int startsect,
 543                                    char *filename, dir_entry *retdent,
 544                                    int dols)
 545 {
 546         __u16 prevcksum = 0xffff;
 547         __u32 curclust = START(retdent);
 548         int files = 0, dirs = 0;
 549
 550         debug("get_dentfromdir: %s\n", filename);
 551
 552         while (1) {
 553                 dir_entry *dentptr;
 554
 555                 int i;
 556
 557                 if (get_cluster(mydata, curclust, get_dentfromdir_block,
 558                                 mydata->clust_size * SECTOR_SIZE) != 0) {
 559                         debug("Error: reading directory block\n");
 560                         return NULL;
 561                 }
 562
 563                 dentptr = (dir_entry *)get_dentfromdir_block;
 564
 565                 for (i = 0; i < DIRENTSPERCLUST; i++) {
 566                         char s_name[14], l_name[VFAT_MAXLEN_BYTES];
 567
 568                         l_name[0] = '\0';
 569                         if (dentptr->name[0] == DELETED_FLAG) {
 570                                 dentptr++;
 571                                 continue;
 572                         }
 573                         if ((dentptr->attr & ATTR_VOLUME)) {
 574 #ifdef CONFIG_SUPPORT_VFAT
 575                                 if ((dentptr->attr & ATTR_VFAT) &&
 576                                     (dentptr-> name[0] & LAST_LONG_ENTRY_MASK)) {
 577                                         prevcksum = ((dir_slot *)dentptr)->alias_checksum;
 578                                         get_vfatname(mydata, curclust,
 579                                                      get_dentfromdir_block,
 580                                                      dentptr, l_name);
 581                                         if (dols) {
 582                                                 int isdir;
 583                                                 char dirc;
 584                                                 int doit = 0;
 585
 586                                                 isdir = (dentptr->attr & ATTR_DIR);
 587
 588                                                 if (isdir) {
 589                                                         dirs++;
 590                                                         dirc = '/';
 591                                                         doit = 1;
 592                                                 } else {
 593                                                         dirc = ' ';
 594                                                         if (l_name[0] != 0) {
 595                                                                 files++;
 596                                                                 doit = 1;
 597                                                         }
 598                                                 }
 599                                                 if (doit) {
 600                                                         if (dirc == ' ') {
 601                                                                 printf(" %8ld   %s%c\n",
 602                                                                         (long)FAT2CPU32(dentptr->size),
 603                                                                         l_name,
 604                                                                         dirc);
 605                                                         } else {
 606                                                                 printf("            %s%c\n",
 607                                                                         l_name,
 608                                                                         dirc);
 609                                                         }
 610                                                 }
 611                                                 dentptr++;
 612                                                 continue;
 613                                         }
 614                                         debug("vfatname: |%s|\n", l_name);
 615                                 } else
 616 #endif
 617                                 {
 618                                         /* Volume label or VFAT entry */
 619                                         dentptr++;
 620                                         continue;
 621                                 }
 622                         }
 623                         if (dentptr->name[0] == 0) {
 624                                 if (dols) {
 625                                         printf("\n%d file(s), %d dir(s)\n\n",
 626                                                 files, dirs);
 627                                 }
 628                                 debug("Dentname == NULL - %d\n", i);
 629                                 return NULL;
 630                         }
 631 #ifdef CONFIG_SUPPORT_VFAT
 632                         if (dols && mkcksum(dentptr->name) == prevcksum) {
 633                                 dentptr++;
 634                                 continue;
 635                         }
 636 #endif
 637                         get_name(dentptr, s_name);
 638                         if (dols) {
 639                                 int isdir = (dentptr->attr & ATTR_DIR);
 640                                 char dirc;
 641                                 int doit = 0;
 642
 643                                 if (isdir) {
 644                                         dirs++;
 645                                         dirc = '/';
 646                                         doit = 1;
 647                                 } else {
 648                                         dirc = ' ';
 649                                         if (s_name[0] != 0) {
 650                                                 files++;
 651                                                 doit = 1;
 652                                         }
 653                                 }
 654
 655                                 if (doit) {
 656                                         if (dirc == ' ') {
 657                                                 printf(" %8ld   %s%c\n",
 658                                                         (long)FAT2CPU32(dentptr->size),
 659                                                         s_name, dirc);
 660                                         } else {
 661                                                 printf("            %s%c\n",
 662                                                         s_name, dirc);
 663                                         }
 664                                 }
 665
 666                                 dentptr++;
 667                                 continue;
 668                         }
 669
 670                         if (strcmp(filename, s_name)
 671                             && strcmp(filename, l_name)) {
 672                                 debug("Mismatch: |%s|%s|\n", s_name, l_name);
 673                                 dentptr++;
 674                                 continue;
 675                         }
 676
 677                         memcpy(retdent, dentptr, sizeof(dir_entry));
 678
 679                         debug("DentName: %s", s_name);
 680                         debug(", start: 0x%x", START(dentptr));
 681                         debug(", size:  0x%x %s\n",
 682                               FAT2CPU32(dentptr->size),
 683                               (dentptr->attr & ATTR_DIR) ? "(DIR)" : "");
 684
 685                         return retdent;
 686                 }
 687
 688                 curclust = get_fatent(mydata, curclust);
 689                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 690                         debug("curclust: 0x%x\n", curclust);
 691                         printf("Invalid FAT entry\n");
 692                         return NULL;
 693                 }
 694         }
 695
 696         return NULL;
 697 }
 698
 699 /*
 700  * Read boot sector and volume info from a FAT filesystem
 701  */
 702 static int
 703 read_bootsectandvi (boot_sector *bs, volume_info *volinfo, int *fatsize)
 704 {
 705         __u8 block[FS_BLOCK_SIZE];
 706
 707         volume_info *vistart;
 708
 709         if (disk_read (0, 1, block) < 0) {
 710                 debug("Error: reading block\n");
 711                 return -1;
 712         }
 713
 714         memcpy(bs, block, sizeof(boot_sector));
 715         bs->reserved = FAT2CPU16(bs->reserved);
 716         bs->fat_length = FAT2CPU16(bs->fat_length);
 717         bs->secs_track = FAT2CPU16(bs->secs_track);
 718         bs->heads = FAT2CPU16(bs->heads);
 719         bs->total_sect = FAT2CPU32(bs->total_sect);
 720
 721         /* FAT32 entries */
 722         if (bs->fat_length == 0) {
 723                 /* Assume FAT32 */
 724                 bs->fat32_length = FAT2CPU32(bs->fat32_length);
 725                 bs->flags = FAT2CPU16(bs->flags);
 726                 bs->root_cluster = FAT2CPU32(bs->root_cluster);
 727                 bs->info_sector = FAT2CPU16(bs->info_sector);
 728                 bs->backup_boot = FAT2CPU16(bs->backup_boot);
 729                 vistart = (volume_info *)(block + sizeof(boot_sector));
 730                 *fatsize = 32;
 731         } else {
 732                 vistart = (volume_info *)&(bs->fat32_length);
 733                 *fatsize = 0;
 734         }
 735         memcpy(volinfo, vistart, sizeof(volume_info));
 736
 737         if (*fatsize == 32) {
 738                 if (strncmp(FAT32_SIGN, vistart->fs_type, SIGNLEN) == 0)
 739                         return 0;
 740         } else {
 741                 if (strncmp(FAT12_SIGN, vistart->fs_type, SIGNLEN) == 0) {
 742                         *fatsize = 12;
 743                         return 0;
 744                 }
 745                 if (strncmp(FAT16_SIGN, vistart->fs_type, SIGNLEN) == 0) {
 746                         *fatsize = 16;
 747                         return 0;
 748                 }
 749         }
 750
 751         debug("Error: broken fs_type sign\n");
 752         return -1;
 753 }
 754
 755 __attribute__ ((__aligned__ (__alignof__ (dir_entry))))
 756 __u8 do_fat_read_block[MAX_CLUSTSIZE];
 757
 758 long
 759 do_fat_read (const char *filename, void *buffer, unsigned long maxsize,
 760              int dols)
 761 {
 762         char fnamecopy[2048];
 763         boot_sector bs;
 764         volume_info volinfo;
 765         fsdata datablock;
 766         fsdata *mydata = &datablock;
 767         dir_entry *dentptr;
 768         __u16 prevcksum = 0xffff;
 769         char *subname = "";
 770         int cursect;
 771         int idx, isdir = 0;
 772         int files = 0, dirs = 0;
 773         long ret = 0;
 774         int firsttime;
 775         int root_cluster;
 776         int j;
 777
 778         if (read_bootsectandvi(&bs, &volinfo, &mydata->fatsize)) {
 779                 debug("Error: reading boot sector\n");
 780                 return -1;
 781         }
 782
 783         root_cluster = bs.root_cluster;
 784
 785         if (mydata->fatsize == 32)
 786                 mydata->fatlength = bs.fat32_length;
 787         else
 788                 mydata->fatlength = bs.fat_length;
 789
 790         mydata->fat_sect = bs.reserved;
 791
 792         cursect = mydata->rootdir_sect
 793                 = mydata->fat_sect + mydata->fatlength * bs.fats;
 794
 795         mydata->clust_size = bs.cluster_size;
 796
 797         if (mydata->fatsize == 32) {
 798                 mydata->data_begin = mydata->rootdir_sect -
 799                                         (mydata->clust_size * 2);
 800         } else {
 801                 int rootdir_size;
 802
 803                 rootdir_size = ((bs.dir_entries[1]  * (int)256 +
 804                                  bs.dir_entries[0]) *
 805                                  sizeof(dir_entry)) /
 806                                  SECTOR_SIZE;
 807                 mydata->data_begin = mydata->rootdir_sect +
 808                                         rootdir_size -
 809                                         (mydata->clust_size * 2);
 810         }
 811
 812         mydata->fatbufnum = -1;
 813
 814 #ifdef CONFIG_SUPPORT_VFAT
 815         debug("VFAT Support enabled\n");
 816 #endif
 817         debug("FAT%d, fat_sect: %d, fatlength: %d\n",
 818                mydata->fatsize, mydata->fat_sect, mydata->fatlength);
 819         debug("Rootdir begins at cluster: %d, sector: %d, offset: %x\n"
 820                "Data begins at: %d\n",
 821                root_cluster,
 822                mydata->rootdir_sect,
 823                mydata->rootdir_sect * SECTOR_SIZE, mydata->data_begin);
 824         debug("Cluster size: %d\n", mydata->clust_size);
 825
 826         /* "cwd" is always the root... */
 827         while (ISDIRDELIM(*filename))
 828                 filename++;
 829
 830         /* Make a copy of the filename and convert it to lowercase */
 831         strcpy(fnamecopy, filename);
 832         downcase(fnamecopy);
 833
 834         if (*fnamecopy == '\0') {
 835                 if (!dols)
 836                         return -1;
 837
 838                 dols = LS_ROOT;
 839         } else if ((idx = dirdelim(fnamecopy)) >= 0) {
 840                 isdir = 1;
 841                 fnamecopy[idx] = '\0';
 842                 subname = fnamecopy + idx + 1;
 843
 844                 /* Handle multiple delimiters */
 845                 while (ISDIRDELIM(*subname))
 846                         subname++;
 847         } else if (dols) {
 848                 isdir = 1;
 849         }
 850
 851         j = 0;
 852         while (1) {
 853                 int i;
 854
 855                 debug("FAT read sect=%d, clust_size=%d, DIRENTSPERBLOCK=%d\n",
 856                         cursect, mydata->clust_size, DIRENTSPERBLOCK);
 857
 858                 if (disk_read(cursect,
 859                                 (mydata->fatsize == 32) ?
 860                                 (mydata->clust_size) :
 861                                 LINEAR_PREFETCH_SIZE,
 862                                 do_fat_read_block) < 0) {
 863                         debug("Error: reading rootdir block\n");
 864                         return -1;
 865                 }
 866
 867                 dentptr = (dir_entry *) do_fat_read_block;
 868
 869                 for (i = 0; i < DIRENTSPERBLOCK; i++) {
 870                         char s_name[14], l_name[VFAT_MAXLEN_BYTES];
 871
 872                         l_name[0] = '\0';
 873                         if (dentptr->name[0] == DELETED_FLAG) {
 874                                 dentptr++;
 875                                 continue;
 876                         }
 877                         if ((dentptr->attr & ATTR_VOLUME)) {
 878 #ifdef CONFIG_SUPPORT_VFAT
 879                                 if ((dentptr->attr & ATTR_VFAT) &&
 880                                     (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
 881                                         prevcksum =
 882                                                 ((dir_slot *)dentptr)->alias_checksum;
 883
 884                                         get_vfatname(mydata,
 885                                                      (mydata->fatsize == 32) ?
 886                                                      root_cluster :
 887                                                      0,
 888                                                      do_fat_read_block,
 889                                                      dentptr, l_name);
 890
 891                                         if (dols == LS_ROOT) {
 892                                                 char dirc;
 893                                                 int doit = 0;
 894                                                 int isdir =
 895                                                         (dentptr->attr & ATTR_DIR);
 896
 897                                                 if (isdir) {
 898                                                         dirs++;
 899                                                         dirc = '/';
 900                                                         doit = 1;
 901                                                 } else {
 902                                                         dirc = ' ';
 903                                                         if (l_name[0] != 0) {
 904                                                                 files++;
 905                                                                 doit = 1;
 906                                                         }
 907                                                 }
 908                                                 if (doit) {
 909                                                         if (dirc == ' ') {
 910                                                                 printf(" %8ld   %s%c\n",
 911                                                                         (long)FAT2CPU32(dentptr->size),
 912                                                                         l_name,
 913                                                                         dirc);
 914                                                         } else {
 915                                                                 printf("            %s%c\n",
 916                                                                         l_name,
 917                                                                         dirc);
 918                                                         }
 919                                                 }
 920                                                 dentptr++;
 921                                                 continue;
 922                                         }
 923                                         debug("Rootvfatname: |%s|\n",
 924                                                l_name);
 925                                 } else
 926 #endif
 927                                 {
 928                                         /* Volume label or VFAT entry */
 929                                         dentptr++;
 930                                         continue;
 931                                 }
 932                         } else if (dentptr->name[0] == 0) {
 933                                 debug("RootDentname == NULL - %d\n", i);
 934                                 if (dols == LS_ROOT) {
 935                                         printf("\n%d file(s), %d dir(s)\n\n",
 936                                                 files, dirs);
 937                                         return 0;
 938                                 }
 939                                 return -1;
 940                         }
 941 #ifdef CONFIG_SUPPORT_VFAT
 942                         else if (dols == LS_ROOT &&
 943                                  mkcksum(dentptr->name) == prevcksum) {
 944                                 dentptr++;
 945                                 continue;
 946                         }
 947 #endif
 948                         get_name(dentptr, s_name);
 949
 950                         if (dols == LS_ROOT) {
 951                                 int isdir = (dentptr->attr & ATTR_DIR);
 952                                 char dirc;
 953                                 int doit = 0;
 954
 955                                 if (isdir) {
 956                                         dirc = '/';
 957                                         if (s_name[0] != 0) {
 958                                                 dirs++;
 959                                                 doit = 1;
 960                                         }
 961                                 } else {
 962                                         dirc = ' ';
 963                                         if (s_name[0] != 0) {
 964                                                 files++;
 965                                                 doit = 1;
 966                                         }
 967                                 }
 968                                 if (doit) {
 969                                         if (dirc == ' ') {
 970                                                 printf(" %8ld   %s%c\n",
 971                                                         (long)FAT2CPU32(dentptr->size),
 972                                                         s_name, dirc);
 973                                         } else {
 974                                                 printf("            %s%c\n",
 975                                                         s_name, dirc);
 976                                         }
 977                                 }
 978                                 dentptr++;
 979                                 continue;
 980                         }
 981
 982                         if (strcmp(fnamecopy, s_name)
 983                             && strcmp(fnamecopy, l_name)) {
 984                                 debug("RootMismatch: |%s|%s|\n", s_name,
 985                                        l_name);
 986                                 dentptr++;
 987                                 continue;
 988                         }
 989
 990                         if (isdir && !(dentptr->attr & ATTR_DIR))
 991                                 return -1;
 992
 993                         debug("RootName: %s", s_name);
 994                         debug(", start: 0x%x", START(dentptr));
 995                         debug(", size:  0x%x %s\n",
 996                                FAT2CPU32(dentptr->size),
 997                                isdir ? "(DIR)" : "");
 998
 999                         goto rootdir_done;      /* We got a match */
1000                 }
1001                 debug("END LOOP: j=%d   clust_size=%d\n", j,
1002                        mydata->clust_size);
1003
1004                 /*
1005                  * On FAT32 we must fetch the FAT entries for the next
1006                  * root directory clusters when a cluster has been
1007                  * completely processed.
1008                  */
1009                 if ((mydata->fatsize == 32) && (++j == mydata->clust_size)) {
1010                         int nxtsect;
1011                         int nxt_clust;
1012
1013                         nxt_clust = get_fatent(mydata, root_cluster);
1014
1015                         nxtsect = mydata->data_begin +
1016                                 (nxt_clust * mydata->clust_size);
1017
1018                         debug("END LOOP: sect=%d, root_clust=%d, "
1019                               "n_sect=%d, n_clust=%d\n",
1020                               cursect, root_cluster,
1021                               nxtsect, nxt_clust);
1022
1023                         root_cluster = nxt_clust;
1024
1025                         cursect = nxtsect;
1026                         j = 0;
1027                 } else {
1028                         cursect++;
1029                 }
1030         }
1031 rootdir_done:
1032
1033         firsttime = 1;
1034
1035         while (isdir) {
1036                 int startsect = mydata->data_begin
1037                         + START(dentptr) * mydata->clust_size;
1038                 dir_entry dent;
1039                 char *nextname = NULL;
1040
1041                 dent = *dentptr;
1042                 dentptr = &dent;
1043
1044                 idx = dirdelim(subname);
1045
1046                 if (idx >= 0) {
1047                         subname[idx] = '\0';
1048                         nextname = subname + idx + 1;
1049                         /* Handle multiple delimiters */
1050                         while (ISDIRDELIM(*nextname))
1051                                 nextname++;
1052                         if (dols && *nextname == '\0')
1053                                 firsttime = 0;
1054                 } else {
1055                         if (dols && firsttime) {
1056                                 firsttime = 0;
1057                         } else {
1058                                 isdir = 0;
1059                         }
1060                 }
1061
1062                 if (get_dentfromdir(mydata, startsect, subname, dentptr,
1063                                      isdir ? 0 : dols) == NULL) {
1064                         if (dols && !isdir)
1065                                 return 0;
1066                         return -1;
1067                 }
1068
1069                 if (idx >= 0) {
1070                         if (!(dentptr->attr & ATTR_DIR))
1071                                 return -1;
1072                         subname = nextname;
1073                 }
1074         }
1075
1076         ret = get_contents(mydata, dentptr, buffer, maxsize);
1077         debug("Size: %d, got: %ld\n", FAT2CPU32(dentptr->size), ret);
1078
1079         return ret;
1080 }
1081
1082 int file_fat_detectfs (void)
1083 {
1084         boot_sector bs;
1085         volume_info volinfo;
1086         int fatsize;
1087         char vol_label[12];
1088
1089         if (cur_dev == NULL) {
1090                 printf("No current device\n");
1091                 return 1;
1092         }
1093
1094 #if defined(CONFIG_CMD_IDE) || \
1095     defined(CONFIG_CMD_MG_DISK) || \
1096     defined(CONFIG_CMD_SATA) || \
1097     defined(CONFIG_CMD_SCSI) || \
1098     defined(CONFIG_CMD_USB) || \
1099     defined(CONFIG_MMC)
1100         printf("Interface:  ");
1101         switch (cur_dev->if_type) {
1102         case IF_TYPE_IDE:
1103                 printf("IDE");
1104                 break;
1105         case IF_TYPE_SATA:
1106                 printf("SATA");
1107                 break;
1108         case IF_TYPE_SCSI:
1109                 printf("SCSI");
1110                 break;
1111         case IF_TYPE_ATAPI:
1112                 printf("ATAPI");
1113                 break;
1114         case IF_TYPE_USB:
1115                 printf("USB");
1116                 break;
1117         case IF_TYPE_DOC:
1118                 printf("DOC");
1119                 break;
1120         case IF_TYPE_MMC:
1121                 printf("MMC");
1122                 break;
1123         default:
1124                 printf("Unknown");
1125         }
1126
1127         printf("\n  Device %d: ", cur_dev->dev);
1128         dev_print(cur_dev);
1129 #endif
1130
1131         if (read_bootsectandvi(&bs, &volinfo, &fatsize)) {
1132                 printf("\nNo valid FAT fs found\n");
1133                 return 1;
1134         }
1135
1136         memcpy(vol_label, volinfo.volume_label, 11);
1137         vol_label[11] = '\0';
1138         volinfo.fs_type[5] = '\0';
1139
1140         printf("Partition %d: Filesystem: %s \"%s\"\n", cur_part,
1141                 volinfo.fs_type, vol_label);
1142
1143         return 0;
1144 }
1145
1146 int file_fat_ls (const char *dir)
1147 {
1148         return do_fat_read(dir, NULL, 0, LS_YES);
1149 }
1150
1151 long file_fat_read (const char *filename, void *buffer, unsigned long maxsize)
1152 {
1153         printf("reading %s\n", filename);
1154         return do_fat_read(filename, buffer, maxsize, LS_NO);
1155 }