git.sur5r.net Git - u-boot/blob - 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 <exports.h>
  31 #include <fat.h>
  32 #include <asm/byteorder.h>
  33 #include <part.h>
  34 #include <malloc.h>
  35 #include <linux/compiler.h>
  36 #include <linux/ctype.h>
  37
  38 /*
  39  * Convert a string to lowercase.
  40  */
  41 static void downcase(char *str)
  42 {
  43         while (*str != '\0') {
  44                 *str = tolower(*str);
  45                 str++;
  46         }
  47 }
  48
  49 static block_dev_desc_t *cur_dev;
  50 static disk_partition_t cur_part_info;
  51
  52 #define DOS_BOOT_MAGIC_OFFSET   0x1fe
  53 #define DOS_FS_TYPE_OFFSET      0x36
  54 #define DOS_FS32_TYPE_OFFSET    0x52
  55
  56 static int disk_read(__u32 block, __u32 nr_blocks, void *buf)
  57 {
  58         if (!cur_dev || !cur_dev->block_read)
  59                 return -1;
  60
  61         return cur_dev->block_read(cur_dev->dev,
  62                         cur_part_info.start + block, nr_blocks, buf);
  63 }
  64
  65 int fat_set_blk_dev(block_dev_desc_t *dev_desc, disk_partition_t *info)
  66 {
  67         ALLOC_CACHE_ALIGN_BUFFER(unsigned char, buffer, dev_desc->blksz);
  68
  69         cur_dev = dev_desc;
  70         cur_part_info = *info;
  71
  72         /* Make sure it has a valid FAT header */
  73         if (disk_read(0, 1, buffer) != 1) {
  74                 cur_dev = NULL;
  75                 return -1;
  76         }
  77
  78         /* Check if it's actually a DOS volume */
  79         if (memcmp(buffer + DOS_BOOT_MAGIC_OFFSET, "\x55\xAA", 2)) {
  80                 cur_dev = NULL;
  81                 return -1;
  82         }
  83
  84         /* Check for FAT12/FAT16/FAT32 filesystem */
  85         if (!memcmp(buffer + DOS_FS_TYPE_OFFSET, "FAT", 3))
  86                 return 0;
  87         if (!memcmp(buffer + DOS_FS32_TYPE_OFFSET, "FAT32", 5))
  88                 return 0;
  89
  90         cur_dev = NULL;
  91         return -1;
  92 }
  93
  94 int fat_register_device(block_dev_desc_t *dev_desc, int part_no)
  95 {
  96         disk_partition_t info;
  97
  98         /* First close any currently found FAT filesystem */
  99         cur_dev = NULL;
 100
 101         /* Read the partition table, if present */
 102         if (get_partition_info(dev_desc, part_no, &info)) {
 103                 if (part_no != 0) {
 104                         printf("** Partition %d not valid on device %d **\n",
 105                                         part_no, dev_desc->dev);
 106                         return -1;
 107                 }
 108
 109                 info.start = 0;
 110                 info.size = dev_desc->lba;
 111                 info.blksz = dev_desc->blksz;
 112                 info.name[0] = 0;
 113                 info.type[0] = 0;
 114                 info.bootable = 0;
 115 #ifdef CONFIG_PARTITION_UUIDS
 116                 info.uuid[0] = 0;
 117 #endif
 118         }
 119
 120         return fat_set_blk_dev(dev_desc, &info);
 121 }
 122
 123 /*
 124  * Get the first occurence of a directory delimiter ('/' or '\') in a string.
 125  * Return index into string if found, -1 otherwise.
 126  */
 127 static int dirdelim(char *str)
 128 {
 129         char *start = str;
 130
 131         while (*str != '\0') {
 132                 if (ISDIRDELIM(*str))
 133                         return str - start;
 134                 str++;
 135         }
 136         return -1;
 137 }
 138
 139 /*
 140  * Extract zero terminated short name from a directory entry.
 141  */
 142 static void get_name(dir_entry *dirent, char *s_name)
 143 {
 144         char *ptr;
 145
 146         memcpy(s_name, dirent->name, 8);
 147         s_name[8] = '\0';
 148         ptr = s_name;
 149         while (*ptr && *ptr != ' ')
 150                 ptr++;
 151         if (dirent->ext[0] && dirent->ext[0] != ' ') {
 152                 *ptr = '.';
 153                 ptr++;
 154                 memcpy(ptr, dirent->ext, 3);
 155                 ptr[3] = '\0';
 156                 while (*ptr && *ptr != ' ')
 157                         ptr++;
 158         }
 159         *ptr = '\0';
 160         if (*s_name == DELETED_FLAG)
 161                 *s_name = '\0';
 162         else if (*s_name == aRING)
 163                 *s_name = DELETED_FLAG;
 164         downcase(s_name);
 165 }
 166
 167 /*
 168  * Get the entry at index 'entry' in a FAT (12/16/32) table.
 169  * On failure 0x00 is returned.
 170  */
 171 static __u32 get_fatent(fsdata *mydata, __u32 entry)
 172 {
 173         __u32 bufnum;
 174         __u32 off16, offset;
 175         __u32 ret = 0x00;
 176         __u16 val1, val2;
 177
 178         switch (mydata->fatsize) {
 179         case 32:
 180                 bufnum = entry / FAT32BUFSIZE;
 181                 offset = entry - bufnum * FAT32BUFSIZE;
 182                 break;
 183         case 16:
 184                 bufnum = entry / FAT16BUFSIZE;
 185                 offset = entry - bufnum * FAT16BUFSIZE;
 186                 break;
 187         case 12:
 188                 bufnum = entry / FAT12BUFSIZE;
 189                 offset = entry - bufnum * FAT12BUFSIZE;
 190                 break;
 191
 192         default:
 193                 /* Unsupported FAT size */
 194                 return ret;
 195         }
 196
 197         debug("FAT%d: entry: 0x%04x = %d, offset: 0x%04x = %d\n",
 198                mydata->fatsize, entry, entry, offset, offset);
 199
 200         /* Read a new block of FAT entries into the cache. */
 201         if (bufnum != mydata->fatbufnum) {
 202                 __u32 getsize = FATBUFBLOCKS;
 203                 __u8 *bufptr = mydata->fatbuf;
 204                 __u32 fatlength = mydata->fatlength;
 205                 __u32 startblock = bufnum * FATBUFBLOCKS;
 206
 207                 if (startblock + getsize > fatlength)
 208                         getsize = fatlength - startblock;
 209
 210                 startblock += mydata->fat_sect; /* Offset from start of disk */
 211
 212                 if (disk_read(startblock, getsize, bufptr) < 0) {
 213                         debug("Error reading FAT blocks\n");
 214                         return ret;
 215                 }
 216                 mydata->fatbufnum = bufnum;
 217         }
 218
 219         /* Get the actual entry from the table */
 220         switch (mydata->fatsize) {
 221         case 32:
 222                 ret = FAT2CPU32(((__u32 *) mydata->fatbuf)[offset]);
 223                 break;
 224         case 16:
 225                 ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[offset]);
 226                 break;
 227         case 12:
 228                 off16 = (offset * 3) / 4;
 229
 230                 switch (offset & 0x3) {
 231                 case 0:
 232                         ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[off16]);
 233                         ret &= 0xfff;
 234                         break;
 235                 case 1:
 236                         val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 237                         val1 &= 0xf000;
 238                         val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
 239                         val2 &= 0x00ff;
 240                         ret = (val2 << 4) | (val1 >> 12);
 241                         break;
 242                 case 2:
 243                         val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 244                         val1 &= 0xff00;
 245                         val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
 246                         val2 &= 0x000f;
 247                         ret = (val2 << 8) | (val1 >> 8);
 248                         break;
 249                 case 3:
 250                         ret = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 251                         ret = (ret & 0xfff0) >> 4;
 252                         break;
 253                 default:
 254                         break;
 255                 }
 256                 break;
 257         }
 258         debug("FAT%d: ret: %08x, offset: %04x\n",
 259                mydata->fatsize, ret, offset);
 260
 261         return ret;
 262 }
 263
 264 /*
 265  * Read at most 'size' bytes from the specified cluster into 'buffer'.
 266  * Return 0 on success, -1 otherwise.
 267  */
 268 static int
 269 get_cluster(fsdata *mydata, __u32 clustnum, __u8 *buffer, unsigned long size)
 270 {
 271         __u32 idx = 0;
 272         __u32 startsect;
 273         int ret;
 274
 275         if (clustnum > 0) {
 276                 startsect = mydata->data_begin +
 277                                 clustnum * mydata->clust_size;
 278         } else {
 279                 startsect = mydata->rootdir_sect;
 280         }
 281
 282         debug("gc - clustnum: %d, startsect: %d\n", clustnum, startsect);
 283
 284         if ((unsigned long)buffer & (ARCH_DMA_MINALIGN - 1)) {
 285                 ALLOC_CACHE_ALIGN_BUFFER(__u8, tmpbuf, mydata->sect_size);
 286
 287                 printf("FAT: Misaligned buffer address (%p)\n", buffer);
 288
 289                 while (size >= mydata->sect_size) {
 290                         ret = disk_read(startsect++, 1, tmpbuf);
 291                         if (ret != 1) {
 292                                 debug("Error reading data (got %d)\n", ret);
 293                                 return -1;
 294                         }
 295
 296                         memcpy(buffer, tmpbuf, mydata->sect_size);
 297                         buffer += mydata->sect_size;
 298                         size -= mydata->sect_size;
 299                 }
 300         } else {
 301                 idx = size / mydata->sect_size;
 302                 ret = disk_read(startsect, idx, buffer);
 303                 if (ret != idx) {
 304                         debug("Error reading data (got %d)\n", ret);
 305                         return -1;
 306                 }
 307                 startsect += idx;
 308                 idx *= mydata->sect_size;
 309                 buffer += idx;
 310                 size -= idx;
 311         }
 312         if (size) {
 313                 ALLOC_CACHE_ALIGN_BUFFER(__u8, tmpbuf, mydata->sect_size);
 314
 315                 ret = disk_read(startsect, 1, tmpbuf);
 316                 if (ret != 1) {
 317                         debug("Error reading data (got %d)\n", ret);
 318                         return -1;
 319                 }
 320
 321                 memcpy(buffer, tmpbuf, size);
 322         }
 323
 324         return 0;
 325 }
 326
 327 /*
 328  * Read at most 'maxsize' bytes from 'pos' in the file associated with 'dentptr'
 329  * into 'buffer'.
 330  * Return the number of bytes read or -1 on fatal errors.
 331  */
 332 __u8 get_contents_vfatname_block[MAX_CLUSTSIZE]
 333         __aligned(ARCH_DMA_MINALIGN);
 334
 335 static long
 336 get_contents(fsdata *mydata, dir_entry *dentptr, unsigned long pos,
 337              __u8 *buffer, unsigned long maxsize)
 338 {
 339         unsigned long filesize = FAT2CPU32(dentptr->size), gotsize = 0;
 340         unsigned int bytesperclust = mydata->clust_size * mydata->sect_size;
 341         __u32 curclust = START(dentptr);
 342         __u32 endclust, newclust;
 343         unsigned long actsize;
 344
 345         debug("Filesize: %ld bytes\n", filesize);
 346
 347         if (pos >= filesize) {
 348                 debug("Read position past EOF: %lu\n", pos);
 349                 return gotsize;
 350         }
 351
 352         if (maxsize > 0 && filesize > pos + maxsize)
 353                 filesize = pos + maxsize;
 354
 355         debug("%ld bytes\n", filesize);
 356
 357         actsize = bytesperclust;
 358
 359         /* go to cluster at pos */
 360         while (actsize <= pos) {
 361                 curclust = get_fatent(mydata, curclust);
 362                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 363                         debug("curclust: 0x%x\n", curclust);
 364                         debug("Invalid FAT entry\n");
 365                         return gotsize;
 366                 }
 367                 actsize += bytesperclust;
 368         }
 369
 370         /* actsize > pos */
 371         actsize -= bytesperclust;
 372         filesize -= actsize;
 373         pos -= actsize;
 374
 375         /* align to beginning of next cluster if any */
 376         if (pos) {
 377                 actsize = min(filesize, bytesperclust);
 378                 if (get_cluster(mydata, curclust, get_contents_vfatname_block,
 379                                 (int)actsize) != 0) {
 380                         printf("Error reading cluster\n");
 381                         return -1;
 382                 }
 383                 filesize -= actsize;
 384                 actsize -= pos;
 385                 memcpy(buffer, get_contents_vfatname_block + pos, actsize);
 386                 gotsize += actsize;
 387                 if (!filesize)
 388                         return gotsize;
 389                 buffer += actsize;
 390
 391                 curclust = get_fatent(mydata, curclust);
 392                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 393                         debug("curclust: 0x%x\n", curclust);
 394                         debug("Invalid FAT entry\n");
 395                         return gotsize;
 396                 }
 397         }
 398
 399         actsize = bytesperclust;
 400         endclust = curclust;
 401
 402         do {
 403                 /* search for consecutive clusters */
 404                 while (actsize < filesize) {
 405                         newclust = get_fatent(mydata, endclust);
 406                         if ((newclust - 1) != endclust)
 407                                 goto getit;
 408                         if (CHECK_CLUST(newclust, mydata->fatsize)) {
 409                                 debug("curclust: 0x%x\n", newclust);
 410                                 debug("Invalid FAT entry\n");
 411                                 return gotsize;
 412                         }
 413                         endclust = newclust;
 414                         actsize += bytesperclust;
 415                 }
 416
 417                 /* get remaining bytes */
 418                 actsize = filesize;
 419                 if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
 420                         printf("Error reading cluster\n");
 421                         return -1;
 422                 }
 423                 gotsize += actsize;
 424                 return gotsize;
 425 getit:
 426                 if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
 427                         printf("Error reading cluster\n");
 428                         return -1;
 429                 }
 430                 gotsize += (int)actsize;
 431                 filesize -= actsize;
 432                 buffer += actsize;
 433
 434                 curclust = get_fatent(mydata, endclust);
 435                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 436                         debug("curclust: 0x%x\n", curclust);
 437                         printf("Invalid FAT entry\n");
 438                         return gotsize;
 439                 }
 440                 actsize = bytesperclust;
 441                 endclust = curclust;
 442         } while (1);
 443 }
 444
 445 #ifdef CONFIG_SUPPORT_VFAT
 446 /*
 447  * Extract the file name information from 'slotptr' into 'l_name',
 448  * starting at l_name[*idx].
 449  * Return 1 if terminator (zero byte) is found, 0 otherwise.
 450  */
 451 static int slot2str(dir_slot *slotptr, char *l_name, int *idx)
 452 {
 453         int j;
 454
 455         for (j = 0; j <= 8; j += 2) {
 456                 l_name[*idx] = slotptr->name0_4[j];
 457                 if (l_name[*idx] == 0x00)
 458                         return 1;
 459                 (*idx)++;
 460         }
 461         for (j = 0; j <= 10; j += 2) {
 462                 l_name[*idx] = slotptr->name5_10[j];
 463                 if (l_name[*idx] == 0x00)
 464                         return 1;
 465                 (*idx)++;
 466         }
 467         for (j = 0; j <= 2; j += 2) {
 468                 l_name[*idx] = slotptr->name11_12[j];
 469                 if (l_name[*idx] == 0x00)
 470                         return 1;
 471                 (*idx)++;
 472         }
 473
 474         return 0;
 475 }
 476
 477 /*
 478  * Extract the full long filename starting at 'retdent' (which is really
 479  * a slot) into 'l_name'. If successful also copy the real directory entry
 480  * into 'retdent'
 481  * Return 0 on success, -1 otherwise.
 482  */
 483 static int
 484 get_vfatname(fsdata *mydata, int curclust, __u8 *cluster,
 485              dir_entry *retdent, char *l_name)
 486 {
 487         dir_entry *realdent;
 488         dir_slot *slotptr = (dir_slot *)retdent;
 489         __u8 *buflimit = cluster + mydata->sect_size * ((curclust == 0) ?
 490                                                         PREFETCH_BLOCKS :
 491                                                         mydata->clust_size);
 492         __u8 counter = (slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff;
 493         int idx = 0;
 494
 495         if (counter > VFAT_MAXSEQ) {
 496                 debug("Error: VFAT name is too long\n");
 497                 return -1;
 498         }
 499
 500         while ((__u8 *)slotptr < buflimit) {
 501                 if (counter == 0)
 502                         break;
 503                 if (((slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff) != counter)
 504                         return -1;
 505                 slotptr++;
 506                 counter--;
 507         }
 508
 509         if ((__u8 *)slotptr >= buflimit) {
 510                 dir_slot *slotptr2;
 511
 512                 if (curclust == 0)
 513                         return -1;
 514                 curclust = get_fatent(mydata, curclust);
 515                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 516                         debug("curclust: 0x%x\n", curclust);
 517                         printf("Invalid FAT entry\n");
 518                         return -1;
 519                 }
 520
 521                 if (get_cluster(mydata, curclust, get_contents_vfatname_block,
 522                                 mydata->clust_size * mydata->sect_size) != 0) {
 523                         debug("Error: reading directory block\n");
 524                         return -1;
 525                 }
 526
 527                 slotptr2 = (dir_slot *)get_contents_vfatname_block;
 528                 while (counter > 0) {
 529                         if (((slotptr2->id & ~LAST_LONG_ENTRY_MASK)
 530                             & 0xff) != counter)
 531                                 return -1;
 532                         slotptr2++;
 533                         counter--;
 534                 }
 535
 536                 /* Save the real directory entry */
 537                 realdent = (dir_entry *)slotptr2;
 538                 while ((__u8 *)slotptr2 > get_contents_vfatname_block) {
 539                         slotptr2--;
 540                         slot2str(slotptr2, l_name, &idx);
 541                 }
 542         } else {
 543                 /* Save the real directory entry */
 544                 realdent = (dir_entry *)slotptr;
 545         }
 546
 547         do {
 548                 slotptr--;
 549                 if (slot2str(slotptr, l_name, &idx))
 550                         break;
 551         } while (!(slotptr->id & LAST_LONG_ENTRY_MASK));
 552
 553         l_name[idx] = '\0';
 554         if (*l_name == DELETED_FLAG)
 555                 *l_name = '\0';
 556         else if (*l_name == aRING)
 557                 *l_name = DELETED_FLAG;
 558         downcase(l_name);
 559
 560         /* Return the real directory entry */
 561         memcpy(retdent, realdent, sizeof(dir_entry));
 562
 563         return 0;
 564 }
 565
 566 /* Calculate short name checksum */
 567 static __u8 mkcksum(const char name[8], const char ext[3])
 568 {
 569         int i;
 570
 571         __u8 ret = 0;
 572
 573         for (i = 0; i < 8; i++)
 574                 ret = (((ret & 1) << 7) | ((ret & 0xfe) >> 1)) + name[i];
 575         for (i = 0; i < 3; i++)
 576                 ret = (((ret & 1) << 7) | ((ret & 0xfe) >> 1)) + ext[i];
 577
 578         return ret;
 579 }
 580 #endif  /* CONFIG_SUPPORT_VFAT */
 581
 582 /*
 583  * Get the directory entry associated with 'filename' from the directory
 584  * starting at 'startsect'
 585  */
 586 __u8 get_dentfromdir_block[MAX_CLUSTSIZE]
 587         __aligned(ARCH_DMA_MINALIGN);
 588
 589 static dir_entry *get_dentfromdir(fsdata *mydata, int startsect,
 590                                   char *filename, dir_entry *retdent,
 591                                   int dols)
 592 {
 593         __u16 prevcksum = 0xffff;
 594         __u32 curclust = START(retdent);
 595         int files = 0, dirs = 0;
 596
 597         debug("get_dentfromdir: %s\n", filename);
 598
 599         while (1) {
 600                 dir_entry *dentptr;
 601
 602                 int i;
 603
 604                 if (get_cluster(mydata, curclust, get_dentfromdir_block,
 605                                 mydata->clust_size * mydata->sect_size) != 0) {
 606                         debug("Error: reading directory block\n");
 607                         return NULL;
 608                 }
 609
 610                 dentptr = (dir_entry *)get_dentfromdir_block;
 611
 612                 for (i = 0; i < DIRENTSPERCLUST; i++) {
 613                         char s_name[14], l_name[VFAT_MAXLEN_BYTES];
 614
 615                         l_name[0] = '\0';
 616                         if (dentptr->name[0] == DELETED_FLAG) {
 617                                 dentptr++;
 618                                 continue;
 619                         }
 620                         if ((dentptr->attr & ATTR_VOLUME)) {
 621 #ifdef CONFIG_SUPPORT_VFAT
 622                                 if ((dentptr->attr & ATTR_VFAT) == ATTR_VFAT &&
 623                                     (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
 624                                         prevcksum = ((dir_slot *)dentptr)->alias_checksum;
 625                                         get_vfatname(mydata, curclust,
 626                                                      get_dentfromdir_block,
 627                                                      dentptr, l_name);
 628                                         if (dols) {
 629                                                 int isdir;
 630                                                 char dirc;
 631                                                 int doit = 0;
 632
 633                                                 isdir = (dentptr->attr & ATTR_DIR);
 634
 635                                                 if (isdir) {
 636                                                         dirs++;
 637                                                         dirc = '/';
 638                                                         doit = 1;
 639                                                 } else {
 640                                                         dirc = ' ';
 641                                                         if (l_name[0] != 0) {
 642                                                                 files++;
 643                                                                 doit = 1;
 644                                                         }
 645                                                 }
 646                                                 if (doit) {
 647                                                         if (dirc == ' ') {
 648                                                                 printf(" %8ld   %s%c\n",
 649                                                                         (long)FAT2CPU32(dentptr->size),
 650                                                                         l_name,
 651                                                                         dirc);
 652                                                         } else {
 653                                                                 printf("            %s%c\n",
 654                                                                         l_name,
 655                                                                         dirc);
 656                                                         }
 657                                                 }
 658                                                 dentptr++;
 659                                                 continue;
 660                                         }
 661                                         debug("vfatname: |%s|\n", l_name);
 662                                 } else
 663 #endif
 664                                 {
 665                                         /* Volume label or VFAT entry */
 666                                         dentptr++;
 667                                         continue;
 668                                 }
 669                         }
 670                         if (dentptr->name[0] == 0) {
 671                                 if (dols) {
 672                                         printf("\n%d file(s), %d dir(s)\n\n",
 673                                                 files, dirs);
 674                                 }
 675                                 debug("Dentname == NULL - %d\n", i);
 676                                 return NULL;
 677                         }
 678 #ifdef CONFIG_SUPPORT_VFAT
 679                         __u8 csum = mkcksum(dentptr->name, dentptr->ext);
 680                         if (dols && csum == prevcksum) {
 681                                 prevcksum = 0xffff;
 682                                 dentptr++;
 683                                 continue;
 684                         }
 685 #endif
 686                         get_name(dentptr, s_name);
 687                         if (dols) {
 688                                 int isdir = (dentptr->attr & ATTR_DIR);
 689                                 char dirc;
 690                                 int doit = 0;
 691
 692                                 if (isdir) {
 693                                         dirs++;
 694                                         dirc = '/';
 695                                         doit = 1;
 696                                 } else {
 697                                         dirc = ' ';
 698                                         if (s_name[0] != 0) {
 699                                                 files++;
 700                                                 doit = 1;
 701                                         }
 702                                 }
 703
 704                                 if (doit) {
 705                                         if (dirc == ' ') {
 706                                                 printf(" %8ld   %s%c\n",
 707                                                         (long)FAT2CPU32(dentptr->size),
 708                                                         s_name, dirc);
 709                                         } else {
 710                                                 printf("            %s%c\n",
 711                                                         s_name, dirc);
 712                                         }
 713                                 }
 714
 715                                 dentptr++;
 716                                 continue;
 717                         }
 718
 719                         if (strcmp(filename, s_name)
 720                             && strcmp(filename, l_name)) {
 721                                 debug("Mismatch: |%s|%s|\n", s_name, l_name);
 722                                 dentptr++;
 723                                 continue;
 724                         }
 725
 726                         memcpy(retdent, dentptr, sizeof(dir_entry));
 727
 728                         debug("DentName: %s", s_name);
 729                         debug(", start: 0x%x", START(dentptr));
 730                         debug(", size:  0x%x %s\n",
 731                               FAT2CPU32(dentptr->size),
 732                               (dentptr->attr & ATTR_DIR) ? "(DIR)" : "");
 733
 734                         return retdent;
 735                 }
 736
 737                 curclust = get_fatent(mydata, curclust);
 738                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 739                         debug("curclust: 0x%x\n", curclust);
 740                         printf("Invalid FAT entry\n");
 741                         return NULL;
 742                 }
 743         }
 744
 745         return NULL;
 746 }
 747
 748 /*
 749  * Read boot sector and volume info from a FAT filesystem
 750  */
 751 static int
 752 read_bootsectandvi(boot_sector *bs, volume_info *volinfo, int *fatsize)
 753 {
 754         __u8 *block;
 755         volume_info *vistart;
 756         int ret = 0;
 757
 758         if (cur_dev == NULL) {
 759                 debug("Error: no device selected\n");
 760                 return -1;
 761         }
 762
 763         block = memalign(ARCH_DMA_MINALIGN, cur_dev->blksz);
 764         if (block == NULL) {
 765                 debug("Error: allocating block\n");
 766                 return -1;
 767         }
 768
 769         if (disk_read(0, 1, block) < 0) {
 770                 debug("Error: reading block\n");
 771                 goto fail;
 772         }
 773
 774         memcpy(bs, block, sizeof(boot_sector));
 775         bs->reserved = FAT2CPU16(bs->reserved);
 776         bs->fat_length = FAT2CPU16(bs->fat_length);
 777         bs->secs_track = FAT2CPU16(bs->secs_track);
 778         bs->heads = FAT2CPU16(bs->heads);
 779         bs->total_sect = FAT2CPU32(bs->total_sect);
 780
 781         /* FAT32 entries */
 782         if (bs->fat_length == 0) {
 783                 /* Assume FAT32 */
 784                 bs->fat32_length = FAT2CPU32(bs->fat32_length);
 785                 bs->flags = FAT2CPU16(bs->flags);
 786                 bs->root_cluster = FAT2CPU32(bs->root_cluster);
 787                 bs->info_sector = FAT2CPU16(bs->info_sector);
 788                 bs->backup_boot = FAT2CPU16(bs->backup_boot);
 789                 vistart = (volume_info *)(block + sizeof(boot_sector));
 790                 *fatsize = 32;
 791         } else {
 792                 vistart = (volume_info *)&(bs->fat32_length);
 793                 *fatsize = 0;
 794         }
 795         memcpy(volinfo, vistart, sizeof(volume_info));
 796
 797         if (*fatsize == 32) {
 798                 if (strncmp(FAT32_SIGN, vistart->fs_type, SIGNLEN) == 0)
 799                         goto exit;
 800         } else {
 801                 if (strncmp(FAT12_SIGN, vistart->fs_type, SIGNLEN) == 0) {
 802                         *fatsize = 12;
 803                         goto exit;
 804                 }
 805                 if (strncmp(FAT16_SIGN, vistart->fs_type, SIGNLEN) == 0) {
 806                         *fatsize = 16;
 807                         goto exit;
 808                 }
 809         }
 810
 811         debug("Error: broken fs_type sign\n");
 812 fail:
 813         ret = -1;
 814 exit:
 815         free(block);
 816         return ret;
 817 }
 818
 819 __u8 do_fat_read_at_block[MAX_CLUSTSIZE]
 820         __aligned(ARCH_DMA_MINALIGN);
 821
 822 long
 823 do_fat_read_at(const char *filename, unsigned long pos, void *buffer,
 824                unsigned long maxsize, int dols)
 825 {
 826         char fnamecopy[2048];
 827         boot_sector bs;
 828         volume_info volinfo;
 829         fsdata datablock;
 830         fsdata *mydata = &datablock;
 831         dir_entry *dentptr = NULL;
 832         __u16 prevcksum = 0xffff;
 833         char *subname = "";
 834         __u32 cursect;
 835         int idx, isdir = 0;
 836         int files = 0, dirs = 0;
 837         long ret = -1;
 838         int firsttime;
 839         __u32 root_cluster = 0;
 840         int rootdir_size = 0;
 841         int j;
 842
 843         if (read_bootsectandvi(&bs, &volinfo, &mydata->fatsize)) {
 844                 debug("Error: reading boot sector\n");
 845                 return -1;
 846         }
 847
 848         if (mydata->fatsize == 32) {
 849                 root_cluster = bs.root_cluster;
 850                 mydata->fatlength = bs.fat32_length;
 851         } else {
 852                 mydata->fatlength = bs.fat_length;
 853         }
 854
 855         mydata->fat_sect = bs.reserved;
 856
 857         cursect = mydata->rootdir_sect
 858                 = mydata->fat_sect + mydata->fatlength * bs.fats;
 859
 860         mydata->sect_size = (bs.sector_size[1] << 8) + bs.sector_size[0];
 861         mydata->clust_size = bs.cluster_size;
 862         if (mydata->sect_size != cur_part_info.blksz) {
 863                 printf("Error: FAT sector size mismatch (fs=%hu, dev=%lu)\n",
 864                                 mydata->sect_size, cur_part_info.blksz);
 865                 return -1;
 866         }
 867
 868         if (mydata->fatsize == 32) {
 869                 mydata->data_begin = mydata->rootdir_sect -
 870                                         (mydata->clust_size * 2);
 871         } else {
 872                 rootdir_size = ((bs.dir_entries[1]  * (int)256 +
 873                                  bs.dir_entries[0]) *
 874                                  sizeof(dir_entry)) /
 875                                  mydata->sect_size;
 876                 mydata->data_begin = mydata->rootdir_sect +
 877                                         rootdir_size -
 878                                         (mydata->clust_size * 2);
 879         }
 880
 881         mydata->fatbufnum = -1;
 882         mydata->fatbuf = memalign(ARCH_DMA_MINALIGN, FATBUFSIZE);
 883         if (mydata->fatbuf == NULL) {
 884                 debug("Error: allocating memory\n");
 885                 return -1;
 886         }
 887
 888 #ifdef CONFIG_SUPPORT_VFAT
 889         debug("VFAT Support enabled\n");
 890 #endif
 891         debug("FAT%d, fat_sect: %d, fatlength: %d\n",
 892                mydata->fatsize, mydata->fat_sect, mydata->fatlength);
 893         debug("Rootdir begins at cluster: %d, sector: %d, offset: %x\n"
 894                "Data begins at: %d\n",
 895                root_cluster,
 896                mydata->rootdir_sect,
 897                mydata->rootdir_sect * mydata->sect_size, mydata->data_begin);
 898         debug("Sector size: %d, cluster size: %d\n", mydata->sect_size,
 899               mydata->clust_size);
 900
 901         /* "cwd" is always the root... */
 902         while (ISDIRDELIM(*filename))
 903                 filename++;
 904
 905         /* Make a copy of the filename and convert it to lowercase */
 906         strcpy(fnamecopy, filename);
 907         downcase(fnamecopy);
 908
 909         if (*fnamecopy == '\0') {
 910                 if (!dols)
 911                         goto exit;
 912
 913                 dols = LS_ROOT;
 914         } else if ((idx = dirdelim(fnamecopy)) >= 0) {
 915                 isdir = 1;
 916                 fnamecopy[idx] = '\0';
 917                 subname = fnamecopy + idx + 1;
 918
 919                 /* Handle multiple delimiters */
 920                 while (ISDIRDELIM(*subname))
 921                         subname++;
 922         } else if (dols) {
 923                 isdir = 1;
 924         }
 925
 926         j = 0;
 927         while (1) {
 928                 int i;
 929
 930                 if (j == 0) {
 931                         debug("FAT read sect=%d, clust_size=%d, DIRENTSPERBLOCK=%zd\n",
 932                                 cursect, mydata->clust_size, DIRENTSPERBLOCK);
 933
 934                         if (disk_read(cursect,
 935                                         (mydata->fatsize == 32) ?
 936                                         (mydata->clust_size) :
 937                                         PREFETCH_BLOCKS,
 938                                         do_fat_read_at_block) < 0) {
 939                                 debug("Error: reading rootdir block\n");
 940                                 goto exit;
 941                         }
 942
 943                         dentptr = (dir_entry *) do_fat_read_at_block;
 944                 }
 945
 946                 for (i = 0; i < DIRENTSPERBLOCK; i++) {
 947                         char s_name[14], l_name[VFAT_MAXLEN_BYTES];
 948                         __u8 csum;
 949
 950                         l_name[0] = '\0';
 951                         if (dentptr->name[0] == DELETED_FLAG) {
 952                                 dentptr++;
 953                                 continue;
 954                         }
 955
 956                         csum = mkcksum(dentptr->name, dentptr->ext);
 957                         if (dentptr->attr & ATTR_VOLUME) {
 958 #ifdef CONFIG_SUPPORT_VFAT
 959                                 if ((dentptr->attr & ATTR_VFAT) == ATTR_VFAT &&
 960                                     (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
 961                                         prevcksum =
 962                                                 ((dir_slot *)dentptr)->alias_checksum;
 963
 964                                         get_vfatname(mydata,
 965                                                      root_cluster,
 966                                                      do_fat_read_at_block,
 967                                                      dentptr, l_name);
 968
 969                                         if (dols == LS_ROOT) {
 970                                                 char dirc;
 971                                                 int doit = 0;
 972                                                 int isdir =
 973                                                         (dentptr->attr & ATTR_DIR);
 974
 975                                                 if (isdir) {
 976                                                         dirs++;
 977                                                         dirc = '/';
 978                                                         doit = 1;
 979                                                 } else {
 980                                                         dirc = ' ';
 981                                                         if (l_name[0] != 0) {
 982                                                                 files++;
 983                                                                 doit = 1;
 984                                                         }
 985                                                 }
 986                                                 if (doit) {
 987                                                         if (dirc == ' ') {
 988                                                                 printf(" %8ld   %s%c\n",
 989                                                                         (long)FAT2CPU32(dentptr->size),
 990                                                                         l_name,
 991                                                                         dirc);
 992                                                         } else {
 993                                                                 printf("            %s%c\n",
 994                                                                         l_name,
 995                                                                         dirc);
 996                                                         }
 997                                                 }
 998                                                 dentptr++;
 999                                                 continue;
1000                                         }
1001                                         debug("Rootvfatname: |%s|\n",
1002                                                l_name);
1003                                 } else
1004 #endif
1005                                 {
1006                                         /* Volume label or VFAT entry */
1007                                         dentptr++;
1008                                         continue;
1009                                 }
1010                         } else if (dentptr->name[0] == 0) {
1011                                 debug("RootDentname == NULL - %d\n", i);
1012                                 if (dols == LS_ROOT) {
1013                                         printf("\n%d file(s), %d dir(s)\n\n",
1014                                                 files, dirs);
1015                                         ret = 0;
1016                                 }
1017                                 goto exit;
1018                         }
1019 #ifdef CONFIG_SUPPORT_VFAT
1020                         else if (dols == LS_ROOT && csum == prevcksum) {
1021                                 prevcksum = 0xffff;
1022                                 dentptr++;
1023                                 continue;
1024                         }
1025 #endif
1026                         get_name(dentptr, s_name);
1027
1028                         if (dols == LS_ROOT) {
1029                                 int isdir = (dentptr->attr & ATTR_DIR);
1030                                 char dirc;
1031                                 int doit = 0;
1032
1033                                 if (isdir) {
1034                                         dirc = '/';
1035                                         if (s_name[0] != 0) {
1036                                                 dirs++;
1037                                                 doit = 1;
1038                                         }
1039                                 } else {
1040                                         dirc = ' ';
1041                                         if (s_name[0] != 0) {
1042                                                 files++;
1043                                                 doit = 1;
1044                                         }
1045                                 }
1046                                 if (doit) {
1047                                         if (dirc == ' ') {
1048                                                 printf(" %8ld   %s%c\n",
1049                                                         (long)FAT2CPU32(dentptr->size),
1050                                                         s_name, dirc);
1051                                         } else {
1052                                                 printf("            %s%c\n",
1053                                                         s_name, dirc);
1054                                         }
1055                                 }
1056                                 dentptr++;
1057                                 continue;
1058                         }
1059
1060                         if (strcmp(fnamecopy, s_name)
1061                             && strcmp(fnamecopy, l_name)) {
1062                                 debug("RootMismatch: |%s|%s|\n", s_name,
1063                                        l_name);
1064                                 dentptr++;
1065                                 continue;
1066                         }
1067
1068                         if (isdir && !(dentptr->attr & ATTR_DIR))
1069                                 goto exit;
1070
1071                         debug("RootName: %s", s_name);
1072                         debug(", start: 0x%x", START(dentptr));
1073                         debug(", size:  0x%x %s\n",
1074                                FAT2CPU32(dentptr->size),
1075                                isdir ? "(DIR)" : "");
1076
1077                         goto rootdir_done;      /* We got a match */
1078                 }
1079                 debug("END LOOP: j=%d   clust_size=%d\n", j,
1080                        mydata->clust_size);
1081
1082                 /*
1083                  * On FAT32 we must fetch the FAT entries for the next
1084                  * root directory clusters when a cluster has been
1085                  * completely processed.
1086                  */
1087                 ++j;
1088                 int rootdir_end = 0;
1089                 if (mydata->fatsize == 32) {
1090                         if (j == mydata->clust_size) {
1091                                 int nxtsect = 0;
1092                                 int nxt_clust = 0;
1093
1094                                 nxt_clust = get_fatent(mydata, root_cluster);
1095                                 rootdir_end = CHECK_CLUST(nxt_clust, 32);
1096
1097                                 nxtsect = mydata->data_begin +
1098                                         (nxt_clust * mydata->clust_size);
1099
1100                                 root_cluster = nxt_clust;
1101
1102                                 cursect = nxtsect;
1103                                 j = 0;
1104                         }
1105                 } else {
1106                         if (j == PREFETCH_BLOCKS)
1107                                 j = 0;
1108
1109                         rootdir_end = (++cursect - mydata->rootdir_sect >=
1110                                        rootdir_size);
1111                 }
1112
1113                 /* If end of rootdir reached */
1114                 if (rootdir_end) {
1115                         if (dols == LS_ROOT) {
1116                                 printf("\n%d file(s), %d dir(s)\n\n",
1117                                        files, dirs);
1118                                 ret = 0;
1119                         }
1120                         goto exit;
1121                 }
1122         }
1123 rootdir_done:
1124
1125         firsttime = 1;
1126
1127         while (isdir) {
1128                 int startsect = mydata->data_begin
1129                         + START(dentptr) * mydata->clust_size;
1130                 dir_entry dent;
1131                 char *nextname = NULL;
1132
1133                 dent = *dentptr;
1134                 dentptr = &dent;
1135
1136                 idx = dirdelim(subname);
1137
1138                 if (idx >= 0) {
1139                         subname[idx] = '\0';
1140                         nextname = subname + idx + 1;
1141                         /* Handle multiple delimiters */
1142                         while (ISDIRDELIM(*nextname))
1143                                 nextname++;
1144                         if (dols && *nextname == '\0')
1145                                 firsttime = 0;
1146                 } else {
1147                         if (dols && firsttime) {
1148                                 firsttime = 0;
1149                         } else {
1150                                 isdir = 0;
1151                         }
1152                 }
1153
1154                 if (get_dentfromdir(mydata, startsect, subname, dentptr,
1155                                      isdir ? 0 : dols) == NULL) {
1156                         if (dols && !isdir)
1157                                 ret = 0;
1158                         goto exit;
1159                 }
1160
1161                 if (isdir && !(dentptr->attr & ATTR_DIR))
1162                         goto exit;
1163
1164                 if (idx >= 0)
1165                         subname = nextname;
1166         }
1167
1168         ret = get_contents(mydata, dentptr, pos, buffer, maxsize);
1169         debug("Size: %d, got: %ld\n", FAT2CPU32(dentptr->size), ret);
1170
1171 exit:
1172         free(mydata->fatbuf);
1173         return ret;
1174 }
1175
1176 long
1177 do_fat_read(const char *filename, void *buffer, unsigned long maxsize, int dols)
1178 {
1179         return do_fat_read_at(filename, 0, buffer, maxsize, dols);
1180 }
1181
1182 int file_fat_detectfs(void)
1183 {
1184         boot_sector bs;
1185         volume_info volinfo;
1186         int fatsize;
1187         char vol_label[12];
1188
1189         if (cur_dev == NULL) {
1190                 printf("No current device\n");
1191                 return 1;
1192         }
1193
1194 #if defined(CONFIG_CMD_IDE) || \
1195     defined(CONFIG_CMD_SATA) || \
1196     defined(CONFIG_CMD_SCSI) || \
1197     defined(CONFIG_CMD_USB) || \
1198     defined(CONFIG_MMC)
1199         printf("Interface:  ");
1200         switch (cur_dev->if_type) {
1201         case IF_TYPE_IDE:
1202                 printf("IDE");
1203                 break;
1204         case IF_TYPE_SATA:
1205                 printf("SATA");
1206                 break;
1207         case IF_TYPE_SCSI:
1208                 printf("SCSI");
1209                 break;
1210         case IF_TYPE_ATAPI:
1211                 printf("ATAPI");
1212                 break;
1213         case IF_TYPE_USB:
1214                 printf("USB");
1215                 break;
1216         case IF_TYPE_DOC:
1217                 printf("DOC");
1218                 break;
1219         case IF_TYPE_MMC:
1220                 printf("MMC");
1221                 break;
1222         default:
1223                 printf("Unknown");
1224         }
1225
1226         printf("\n  Device %d: ", cur_dev->dev);
1227         dev_print(cur_dev);
1228 #endif
1229
1230         if (read_bootsectandvi(&bs, &volinfo, &fatsize)) {
1231                 printf("\nNo valid FAT fs found\n");
1232                 return 1;
1233         }
1234
1235         memcpy(vol_label, volinfo.volume_label, 11);
1236         vol_label[11] = '\0';
1237         volinfo.fs_type[5] = '\0';
1238
1239         printf("Filesystem: %s \"%s\"\n", volinfo.fs_type, vol_label);
1240
1241         return 0;
1242 }
1243
1244 int file_fat_ls(const char *dir)
1245 {
1246         return do_fat_read(dir, NULL, 0, LS_YES);
1247 }
1248
1249 long file_fat_read_at(const char *filename, unsigned long pos, void *buffer,
1250                       unsigned long maxsize)
1251 {
1252         printf("reading %s\n", filename);
1253         return do_fat_read_at(filename, pos, buffer, maxsize, LS_NO);
1254 }
1255
1256 long file_fat_read(const char *filename, void *buffer, unsigned long maxsize)
1257 {
1258         return file_fat_read_at(filename, 0, buffer, maxsize);
1259 }