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
  37 /*
  38  * Convert a string to lowercase.
  39  */
  40 static void downcase (char *str)
  41 {
  42         while (*str != '\0') {
  43                 TOLOWER(*str);
  44                 str++;
  45         }
  46 }
  47
  48 static block_dev_desc_t *cur_dev;
  49 static unsigned int cur_part_nr;
  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_register_device (block_dev_desc_t * dev_desc, int part_no)
  66 {
  67         ALLOC_CACHE_ALIGN_BUFFER(unsigned char, buffer, dev_desc->blksz);
  68
  69         /* First close any currently found FAT filesystem */
  70         cur_dev = NULL;
  71
  72 #if (defined(CONFIG_CMD_IDE) || \
  73      defined(CONFIG_CMD_MG_DISK) || \
  74      defined(CONFIG_CMD_SATA) || \
  75      defined(CONFIG_CMD_SCSI) || \
  76      defined(CONFIG_CMD_USB) || \
  77      defined(CONFIG_MMC) || \
  78      defined(CONFIG_SYSTEMACE) )
  79
  80         /* Read the partition table, if present */
  81         if (!get_partition_info(dev_desc, part_no, &cur_part_info)) {
  82                 cur_dev = dev_desc;
  83                 cur_part_nr = part_no;
  84         }
  85 #endif
  86
  87         /* Otherwise it might be a superfloppy (whole-disk FAT filesystem) */
  88         if (!cur_dev) {
  89                 if (part_no != 1) {
  90                         printf("** Partition %d not valid on device %d **\n",
  91                                         part_no, dev_desc->dev);
  92                         return -1;
  93                 }
  94
  95                 cur_dev = dev_desc;
  96                 cur_part_nr = 1;
  97                 cur_part_info.start = 0;
  98                 cur_part_info.size = dev_desc->lba;
  99                 cur_part_info.blksz = dev_desc->blksz;
 100                 memset(cur_part_info.name, 0, sizeof(cur_part_info.name));
 101                 memset(cur_part_info.type, 0, sizeof(cur_part_info.type));
 102         }
 103
 104         /* Make sure it has a valid FAT header */
 105         if (disk_read(0, 1, buffer) != 1) {
 106                 cur_dev = NULL;
 107                 return -1;
 108         }
 109
 110         /* Check if it's actually a DOS volume */
 111         if (memcmp(buffer + DOS_BOOT_MAGIC_OFFSET, "\x55\xAA", 2)) {
 112                 cur_dev = NULL;
 113                 return -1;
 114         }
 115
 116         /* Check for FAT12/FAT16/FAT32 filesystem */
 117         if (!memcmp(buffer + DOS_FS_TYPE_OFFSET, "FAT", 3))
 118                 return 0;
 119         if (!memcmp(buffer + DOS_FS32_TYPE_OFFSET, "FAT32", 5))
 120                 return 0;
 121
 122         cur_dev = NULL;
 123         return -1;
 124 }
 125
 126
 127 /*
 128  * Get the first occurence of a directory delimiter ('/' or '\') in a string.
 129  * Return index into string if found, -1 otherwise.
 130  */
 131 static int dirdelim (char *str)
 132 {
 133         char *start = str;
 134
 135         while (*str != '\0') {
 136                 if (ISDIRDELIM(*str))
 137                         return str - start;
 138                 str++;
 139         }
 140         return -1;
 141 }
 142
 143 /*
 144  * Extract zero terminated short name from a directory entry.
 145  */
 146 static void get_name (dir_entry *dirent, char *s_name)
 147 {
 148         char *ptr;
 149
 150         memcpy(s_name, dirent->name, 8);
 151         s_name[8] = '\0';
 152         ptr = s_name;
 153         while (*ptr && *ptr != ' ')
 154                 ptr++;
 155         if (dirent->ext[0] && dirent->ext[0] != ' ') {
 156                 *ptr = '.';
 157                 ptr++;
 158                 memcpy(ptr, dirent->ext, 3);
 159                 ptr[3] = '\0';
 160                 while (*ptr && *ptr != ' ')
 161                         ptr++;
 162         }
 163         *ptr = '\0';
 164         if (*s_name == DELETED_FLAG)
 165                 *s_name = '\0';
 166         else if (*s_name == aRING)
 167                 *s_name = DELETED_FLAG;
 168         downcase(s_name);
 169 }
 170
 171 /*
 172  * Get the entry at index 'entry' in a FAT (12/16/32) table.
 173  * On failure 0x00 is returned.
 174  */
 175 static __u32 get_fatent (fsdata *mydata, __u32 entry)
 176 {
 177         __u32 bufnum;
 178         __u32 off16, offset;
 179         __u32 ret = 0x00;
 180         __u16 val1, val2;
 181
 182         switch (mydata->fatsize) {
 183         case 32:
 184                 bufnum = entry / FAT32BUFSIZE;
 185                 offset = entry - bufnum * FAT32BUFSIZE;
 186                 break;
 187         case 16:
 188                 bufnum = entry / FAT16BUFSIZE;
 189                 offset = entry - bufnum * FAT16BUFSIZE;
 190                 break;
 191         case 12:
 192                 bufnum = entry / FAT12BUFSIZE;
 193                 offset = entry - bufnum * FAT12BUFSIZE;
 194                 break;
 195
 196         default:
 197                 /* Unsupported FAT size */
 198                 return ret;
 199         }
 200
 201         debug("FAT%d: entry: 0x%04x = %d, offset: 0x%04x = %d\n",
 202                mydata->fatsize, entry, entry, offset, offset);
 203
 204         /* Read a new block of FAT entries into the cache. */
 205         if (bufnum != mydata->fatbufnum) {
 206                 __u32 getsize = FATBUFBLOCKS;
 207                 __u8 *bufptr = mydata->fatbuf;
 208                 __u32 fatlength = mydata->fatlength;
 209                 __u32 startblock = bufnum * FATBUFBLOCKS;
 210
 211                 if (getsize > fatlength)
 212                         getsize = fatlength;
 213
 214                 fatlength *= mydata->sect_size; /* We want it in bytes now */
 215                 startblock += mydata->fat_sect; /* Offset from start of disk */
 216
 217                 if (disk_read(startblock, getsize, bufptr) < 0) {
 218                         debug("Error reading FAT blocks\n");
 219                         return ret;
 220                 }
 221                 mydata->fatbufnum = bufnum;
 222         }
 223
 224         /* Get the actual entry from the table */
 225         switch (mydata->fatsize) {
 226         case 32:
 227                 ret = FAT2CPU32(((__u32 *) mydata->fatbuf)[offset]);
 228                 break;
 229         case 16:
 230                 ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[offset]);
 231                 break;
 232         case 12:
 233                 off16 = (offset * 3) / 4;
 234
 235                 switch (offset & 0x3) {
 236                 case 0:
 237                         ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[off16]);
 238                         ret &= 0xfff;
 239                         break;
 240                 case 1:
 241                         val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 242                         val1 &= 0xf000;
 243                         val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
 244                         val2 &= 0x00ff;
 245                         ret = (val2 << 4) | (val1 >> 12);
 246                         break;
 247                 case 2:
 248                         val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 249                         val1 &= 0xff00;
 250                         val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
 251                         val2 &= 0x000f;
 252                         ret = (val2 << 8) | (val1 >> 8);
 253                         break;
 254                 case 3:
 255                         ret = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 256                         ret = (ret & 0xfff0) >> 4;
 257                         break;
 258                 default:
 259                         break;
 260                 }
 261                 break;
 262         }
 263         debug("FAT%d: ret: %08x, offset: %04x\n",
 264                mydata->fatsize, ret, offset);
 265
 266         return ret;
 267 }
 268
 269 /*
 270  * Read at most 'size' bytes from the specified cluster into 'buffer'.
 271  * Return 0 on success, -1 otherwise.
 272  */
 273 static int
 274 get_cluster (fsdata *mydata, __u32 clustnum, __u8 *buffer,
 275              unsigned long size)
 276 {
 277         __u32 idx = 0;
 278         __u32 startsect;
 279         __u32 nr_sect;
 280         int ret;
 281
 282         if (clustnum > 0) {
 283                 startsect = mydata->data_begin +
 284                                 clustnum * mydata->clust_size;
 285         } else {
 286                 startsect = mydata->rootdir_sect;
 287         }
 288
 289         debug("gc - clustnum: %d, startsect: %d\n", clustnum, startsect);
 290
 291         nr_sect = size / mydata->sect_size;
 292         ret = disk_read(startsect, nr_sect, buffer);
 293         if (ret != nr_sect) {
 294                 debug("Error reading data (got %d)\n", ret);
 295                 return -1;
 296         }
 297         if (size % mydata->sect_size) {
 298                 ALLOC_CACHE_ALIGN_BUFFER(__u8, tmpbuf, mydata->sect_size);
 299
 300                 idx = size / mydata->sect_size;
 301                 ret = disk_read(startsect + idx, 1, tmpbuf);
 302                 if (ret != 1) {
 303                         debug("Error reading data (got %d)\n", ret);
 304                         return -1;
 305                 }
 306                 buffer += idx * mydata->sect_size;
 307
 308                 memcpy(buffer, tmpbuf, size % mydata->sect_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 * mydata->sect_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 __u8 get_vfatname_block[MAX_CLUSTSIZE]
 434         __aligned(ARCH_DMA_MINALIGN);
 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 + mydata->sect_size * ((curclust == 0) ?
 443                                                         PREFETCH_BLOCKS :
 444                                                         mydata->clust_size);
 445         __u8 counter = (slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff;
 446         int idx = 0;
 447
 448         if (counter > VFAT_MAXSEQ) {
 449                 debug("Error: VFAT name is too long\n");
 450                 return -1;
 451         }
 452
 453         while ((__u8 *)slotptr < buflimit) {
 454                 if (counter == 0)
 455                         break;
 456                 if (((slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff) != counter)
 457                         return -1;
 458                 slotptr++;
 459                 counter--;
 460         }
 461
 462         if ((__u8 *)slotptr >= buflimit) {
 463                 dir_slot *slotptr2;
 464
 465                 if (curclust == 0)
 466                         return -1;
 467                 curclust = get_fatent(mydata, curclust);
 468                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 469                         debug("curclust: 0x%x\n", curclust);
 470                         printf("Invalid FAT entry\n");
 471                         return -1;
 472                 }
 473
 474                 if (get_cluster(mydata, curclust, get_vfatname_block,
 475                                 mydata->clust_size * mydata->sect_size) != 0) {
 476                         debug("Error: reading directory block\n");
 477                         return -1;
 478                 }
 479
 480                 slotptr2 = (dir_slot *)get_vfatname_block;
 481                 while (counter > 0) {
 482                         if (((slotptr2->id & ~LAST_LONG_ENTRY_MASK)
 483                             & 0xff) != counter)
 484                                 return -1;
 485                         slotptr2++;
 486                         counter--;
 487                 }
 488
 489                 /* Save the real directory entry */
 490                 realdent = (dir_entry *)slotptr2;
 491                 while ((__u8 *)slotptr2 > get_vfatname_block) {
 492                         slotptr2--;
 493                         slot2str(slotptr2, l_name, &idx);
 494                 }
 495         } else {
 496                 /* Save the real directory entry */
 497                 realdent = (dir_entry *)slotptr;
 498         }
 499
 500         do {
 501                 slotptr--;
 502                 if (slot2str(slotptr, l_name, &idx))
 503                         break;
 504         } while (!(slotptr->id & LAST_LONG_ENTRY_MASK));
 505
 506         l_name[idx] = '\0';
 507         if (*l_name == DELETED_FLAG)
 508                 *l_name = '\0';
 509         else if (*l_name == aRING)
 510                 *l_name = DELETED_FLAG;
 511         downcase(l_name);
 512
 513         /* Return the real directory entry */
 514         memcpy(retdent, realdent, sizeof(dir_entry));
 515
 516         return 0;
 517 }
 518
 519 /* Calculate short name checksum */
 520 static __u8 mkcksum (const char *str)
 521 {
 522         int i;
 523
 524         __u8 ret = 0;
 525
 526         for (i = 0; i < 11; i++) {
 527                 ret = (((ret & 1) << 7) | ((ret & 0xfe) >> 1)) + str[i];
 528         }
 529
 530         return ret;
 531 }
 532 #endif  /* CONFIG_SUPPORT_VFAT */
 533
 534 /*
 535  * Get the directory entry associated with 'filename' from the directory
 536  * starting at 'startsect'
 537  */
 538 __u8 get_dentfromdir_block[MAX_CLUSTSIZE]
 539         __aligned(ARCH_DMA_MINALIGN);
 540
 541 static dir_entry *get_dentfromdir (fsdata *mydata, int startsect,
 542                                    char *filename, dir_entry *retdent,
 543                                    int dols)
 544 {
 545         __u16 prevcksum = 0xffff;
 546         __u32 curclust = START(retdent);
 547         int files = 0, dirs = 0;
 548
 549         debug("get_dentfromdir: %s\n", filename);
 550
 551         while (1) {
 552                 dir_entry *dentptr;
 553
 554                 int i;
 555
 556                 if (get_cluster(mydata, curclust, get_dentfromdir_block,
 557                                 mydata->clust_size * mydata->sect_size) != 0) {
 558                         debug("Error: reading directory block\n");
 559                         return NULL;
 560                 }
 561
 562                 dentptr = (dir_entry *)get_dentfromdir_block;
 563
 564                 for (i = 0; i < DIRENTSPERCLUST; i++) {
 565                         char s_name[14], l_name[VFAT_MAXLEN_BYTES];
 566
 567                         l_name[0] = '\0';
 568                         if (dentptr->name[0] == DELETED_FLAG) {
 569                                 dentptr++;
 570                                 continue;
 571                         }
 572                         if ((dentptr->attr & ATTR_VOLUME)) {
 573 #ifdef CONFIG_SUPPORT_VFAT
 574                                 if ((dentptr->attr & ATTR_VFAT) == ATTR_VFAT &&
 575                                     (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
 576                                         prevcksum = ((dir_slot *)dentptr)->alias_checksum;
 577                                         get_vfatname(mydata, curclust,
 578                                                      get_dentfromdir_block,
 579                                                      dentptr, l_name);
 580                                         if (dols) {
 581                                                 int isdir;
 582                                                 char dirc;
 583                                                 int doit = 0;
 584
 585                                                 isdir = (dentptr->attr & ATTR_DIR);
 586
 587                                                 if (isdir) {
 588                                                         dirs++;
 589                                                         dirc = '/';
 590                                                         doit = 1;
 591                                                 } else {
 592                                                         dirc = ' ';
 593                                                         if (l_name[0] != 0) {
 594                                                                 files++;
 595                                                                 doit = 1;
 596                                                         }
 597                                                 }
 598                                                 if (doit) {
 599                                                         if (dirc == ' ') {
 600                                                                 printf(" %8ld   %s%c\n",
 601                                                                         (long)FAT2CPU32(dentptr->size),
 602                                                                         l_name,
 603                                                                         dirc);
 604                                                         } else {
 605                                                                 printf("            %s%c\n",
 606                                                                         l_name,
 607                                                                         dirc);
 608                                                         }
 609                                                 }
 610                                                 dentptr++;
 611                                                 continue;
 612                                         }
 613                                         debug("vfatname: |%s|\n", l_name);
 614                                 } else
 615 #endif
 616                                 {
 617                                         /* Volume label or VFAT entry */
 618                                         dentptr++;
 619                                         continue;
 620                                 }
 621                         }
 622                         if (dentptr->name[0] == 0) {
 623                                 if (dols) {
 624                                         printf("\n%d file(s), %d dir(s)\n\n",
 625                                                 files, dirs);
 626                                 }
 627                                 debug("Dentname == NULL - %d\n", i);
 628                                 return NULL;
 629                         }
 630 #ifdef CONFIG_SUPPORT_VFAT
 631                         if (dols && mkcksum(dentptr->name) == prevcksum) {
 632                                 prevcksum = 0xffff;
 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;
 706         volume_info *vistart;
 707         int ret = 0;
 708
 709         if (cur_dev == NULL) {
 710                 debug("Error: no device selected\n");
 711                 return -1;
 712         }
 713
 714         block = memalign(ARCH_DMA_MINALIGN, cur_dev->blksz);
 715         if (block == NULL) {
 716                 debug("Error: allocating block\n");
 717                 return -1;
 718         }
 719
 720         if (disk_read (0, 1, block) < 0) {
 721                 debug("Error: reading block\n");
 722                 goto fail;
 723         }
 724
 725         memcpy(bs, block, sizeof(boot_sector));
 726         bs->reserved = FAT2CPU16(bs->reserved);
 727         bs->fat_length = FAT2CPU16(bs->fat_length);
 728         bs->secs_track = FAT2CPU16(bs->secs_track);
 729         bs->heads = FAT2CPU16(bs->heads);
 730         bs->total_sect = FAT2CPU32(bs->total_sect);
 731
 732         /* FAT32 entries */
 733         if (bs->fat_length == 0) {
 734                 /* Assume FAT32 */
 735                 bs->fat32_length = FAT2CPU32(bs->fat32_length);
 736                 bs->flags = FAT2CPU16(bs->flags);
 737                 bs->root_cluster = FAT2CPU32(bs->root_cluster);
 738                 bs->info_sector = FAT2CPU16(bs->info_sector);
 739                 bs->backup_boot = FAT2CPU16(bs->backup_boot);
 740                 vistart = (volume_info *)(block + sizeof(boot_sector));
 741                 *fatsize = 32;
 742         } else {
 743                 vistart = (volume_info *)&(bs->fat32_length);
 744                 *fatsize = 0;
 745         }
 746         memcpy(volinfo, vistart, sizeof(volume_info));
 747
 748         if (*fatsize == 32) {
 749                 if (strncmp(FAT32_SIGN, vistart->fs_type, SIGNLEN) == 0)
 750                         goto exit;
 751         } else {
 752                 if (strncmp(FAT12_SIGN, vistart->fs_type, SIGNLEN) == 0) {
 753                         *fatsize = 12;
 754                         goto exit;
 755                 }
 756                 if (strncmp(FAT16_SIGN, vistart->fs_type, SIGNLEN) == 0) {
 757                         *fatsize = 16;
 758                         goto exit;
 759                 }
 760         }
 761
 762         debug("Error: broken fs_type sign\n");
 763 fail:
 764         ret = -1;
 765 exit:
 766         free(block);
 767         return ret;
 768 }
 769
 770 __u8 do_fat_read_block[MAX_CLUSTSIZE]
 771         __aligned(ARCH_DMA_MINALIGN);
 772
 773 long
 774 do_fat_read (const char *filename, void *buffer, unsigned long maxsize,
 775              int dols)
 776 {
 777         char fnamecopy[2048];
 778         boot_sector bs;
 779         volume_info volinfo;
 780         fsdata datablock;
 781         fsdata *mydata = &datablock;
 782         dir_entry *dentptr;
 783         __u16 prevcksum = 0xffff;
 784         char *subname = "";
 785         __u32 cursect;
 786         int idx, isdir = 0;
 787         int files = 0, dirs = 0;
 788         long ret = -1;
 789         int firsttime;
 790         __u32 root_cluster = 0;
 791         int rootdir_size = 0;
 792         int j;
 793
 794         if (read_bootsectandvi(&bs, &volinfo, &mydata->fatsize)) {
 795                 debug("Error: reading boot sector\n");
 796                 return -1;
 797         }
 798
 799         if (mydata->fatsize == 32) {
 800                 root_cluster = bs.root_cluster;
 801                 mydata->fatlength = bs.fat32_length;
 802         } else {
 803                 mydata->fatlength = bs.fat_length;
 804         }
 805
 806         mydata->fat_sect = bs.reserved;
 807
 808         cursect = mydata->rootdir_sect
 809                 = mydata->fat_sect + mydata->fatlength * bs.fats;
 810
 811         mydata->sect_size = (bs.sector_size[1] << 8) + bs.sector_size[0];
 812         mydata->clust_size = bs.cluster_size;
 813         if (mydata->sect_size != cur_part_info.blksz) {
 814                 printf("Error: FAT sector size mismatch (fs=%hu, dev=%lu)\n",
 815                                 mydata->sect_size, cur_part_info.blksz);
 816                 return -1;
 817         }
 818
 819         if (mydata->fatsize == 32) {
 820                 mydata->data_begin = mydata->rootdir_sect -
 821                                         (mydata->clust_size * 2);
 822         } else {
 823                 rootdir_size = ((bs.dir_entries[1]  * (int)256 +
 824                                  bs.dir_entries[0]) *
 825                                  sizeof(dir_entry)) /
 826                                  mydata->sect_size;
 827                 mydata->data_begin = mydata->rootdir_sect +
 828                                         rootdir_size -
 829                                         (mydata->clust_size * 2);
 830         }
 831
 832         mydata->fatbufnum = -1;
 833         mydata->fatbuf = memalign(ARCH_DMA_MINALIGN, FATBUFSIZE);
 834         if (mydata->fatbuf == NULL) {
 835                 debug("Error: allocating memory\n");
 836                 return -1;
 837         }
 838
 839 #ifdef CONFIG_SUPPORT_VFAT
 840         debug("VFAT Support enabled\n");
 841 #endif
 842         debug("FAT%d, fat_sect: %d, fatlength: %d\n",
 843                mydata->fatsize, mydata->fat_sect, mydata->fatlength);
 844         debug("Rootdir begins at cluster: %d, sector: %d, offset: %x\n"
 845                "Data begins at: %d\n",
 846                root_cluster,
 847                mydata->rootdir_sect,
 848                mydata->rootdir_sect * mydata->sect_size, mydata->data_begin);
 849         debug("Sector size: %d, cluster size: %d\n", mydata->sect_size,
 850               mydata->clust_size);
 851
 852         /* "cwd" is always the root... */
 853         while (ISDIRDELIM(*filename))
 854                 filename++;
 855
 856         /* Make a copy of the filename and convert it to lowercase */
 857         strcpy(fnamecopy, filename);
 858         downcase(fnamecopy);
 859
 860         if (*fnamecopy == '\0') {
 861                 if (!dols)
 862                         goto exit;
 863
 864                 dols = LS_ROOT;
 865         } else if ((idx = dirdelim(fnamecopy)) >= 0) {
 866                 isdir = 1;
 867                 fnamecopy[idx] = '\0';
 868                 subname = fnamecopy + idx + 1;
 869
 870                 /* Handle multiple delimiters */
 871                 while (ISDIRDELIM(*subname))
 872                         subname++;
 873         } else if (dols) {
 874                 isdir = 1;
 875         }
 876
 877         j = 0;
 878         while (1) {
 879                 int i;
 880
 881                 debug("FAT read sect=%d, clust_size=%d, DIRENTSPERBLOCK=%zd\n",
 882                         cursect, mydata->clust_size, DIRENTSPERBLOCK);
 883
 884                 if (disk_read(cursect,
 885                                 (mydata->fatsize == 32) ?
 886                                 (mydata->clust_size) :
 887                                 PREFETCH_BLOCKS,
 888                                 do_fat_read_block) < 0) {
 889                         debug("Error: reading rootdir block\n");
 890                         goto exit;
 891                 }
 892
 893                 dentptr = (dir_entry *) do_fat_read_block;
 894
 895                 for (i = 0; i < DIRENTSPERBLOCK; i++) {
 896                         char s_name[14], l_name[VFAT_MAXLEN_BYTES];
 897
 898                         l_name[0] = '\0';
 899                         if (dentptr->name[0] == DELETED_FLAG) {
 900                                 dentptr++;
 901                                 continue;
 902                         }
 903                         if ((dentptr->attr & ATTR_VOLUME)) {
 904 #ifdef CONFIG_SUPPORT_VFAT
 905                                 if ((dentptr->attr & ATTR_VFAT) == ATTR_VFAT &&
 906                                     (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
 907                                         prevcksum =
 908                                                 ((dir_slot *)dentptr)->alias_checksum;
 909
 910                                         get_vfatname(mydata,
 911                                                      root_cluster,
 912                                                      do_fat_read_block,
 913                                                      dentptr, l_name);
 914
 915                                         if (dols == LS_ROOT) {
 916                                                 char dirc;
 917                                                 int doit = 0;
 918                                                 int isdir =
 919                                                         (dentptr->attr & ATTR_DIR);
 920
 921                                                 if (isdir) {
 922                                                         dirs++;
 923                                                         dirc = '/';
 924                                                         doit = 1;
 925                                                 } else {
 926                                                         dirc = ' ';
 927                                                         if (l_name[0] != 0) {
 928                                                                 files++;
 929                                                                 doit = 1;
 930                                                         }
 931                                                 }
 932                                                 if (doit) {
 933                                                         if (dirc == ' ') {
 934                                                                 printf(" %8ld   %s%c\n",
 935                                                                         (long)FAT2CPU32(dentptr->size),
 936                                                                         l_name,
 937                                                                         dirc);
 938                                                         } else {
 939                                                                 printf("            %s%c\n",
 940                                                                         l_name,
 941                                                                         dirc);
 942                                                         }
 943                                                 }
 944                                                 dentptr++;
 945                                                 continue;
 946                                         }
 947                                         debug("Rootvfatname: |%s|\n",
 948                                                l_name);
 949                                 } else
 950 #endif
 951                                 {
 952                                         /* Volume label or VFAT entry */
 953                                         dentptr++;
 954                                         continue;
 955                                 }
 956                         } else if (dentptr->name[0] == 0) {
 957                                 debug("RootDentname == NULL - %d\n", i);
 958                                 if (dols == LS_ROOT) {
 959                                         printf("\n%d file(s), %d dir(s)\n\n",
 960                                                 files, dirs);
 961                                         ret = 0;
 962                                 }
 963                                 goto exit;
 964                         }
 965 #ifdef CONFIG_SUPPORT_VFAT
 966                         else if (dols == LS_ROOT &&
 967                                  mkcksum(dentptr->name) == prevcksum) {
 968                                 prevcksum = 0xffff;
 969                                 dentptr++;
 970                                 continue;
 971                         }
 972 #endif
 973                         get_name(dentptr, s_name);
 974
 975                         if (dols == LS_ROOT) {
 976                                 int isdir = (dentptr->attr & ATTR_DIR);
 977                                 char dirc;
 978                                 int doit = 0;
 979
 980                                 if (isdir) {
 981                                         dirc = '/';
 982                                         if (s_name[0] != 0) {
 983                                                 dirs++;
 984                                                 doit = 1;
 985                                         }
 986                                 } else {
 987                                         dirc = ' ';
 988                                         if (s_name[0] != 0) {
 989                                                 files++;
 990                                                 doit = 1;
 991                                         }
 992                                 }
 993                                 if (doit) {
 994                                         if (dirc == ' ') {
 995                                                 printf(" %8ld   %s%c\n",
 996                                                         (long)FAT2CPU32(dentptr->size),
 997                                                         s_name, dirc);
 998                                         } else {
 999                                                 printf("            %s%c\n",
1000                                                         s_name, dirc);
1001                                         }
1002                                 }
1003                                 dentptr++;
1004                                 continue;
1005                         }
1006
1007                         if (strcmp(fnamecopy, s_name)
1008                             && strcmp(fnamecopy, l_name)) {
1009                                 debug("RootMismatch: |%s|%s|\n", s_name,
1010                                        l_name);
1011                                 dentptr++;
1012                                 continue;
1013                         }
1014
1015                         if (isdir && !(dentptr->attr & ATTR_DIR))
1016                                 goto exit;
1017
1018                         debug("RootName: %s", s_name);
1019                         debug(", start: 0x%x", START(dentptr));
1020                         debug(", size:  0x%x %s\n",
1021                                FAT2CPU32(dentptr->size),
1022                                isdir ? "(DIR)" : "");
1023
1024                         goto rootdir_done;      /* We got a match */
1025                 }
1026                 debug("END LOOP: j=%d   clust_size=%d\n", j,
1027                        mydata->clust_size);
1028
1029                 /*
1030                  * On FAT32 we must fetch the FAT entries for the next
1031                  * root directory clusters when a cluster has been
1032                  * completely processed.
1033                  */
1034                 ++j;
1035                 int fat32_end = 0;
1036                 if ((mydata->fatsize == 32) && (j == mydata->clust_size)) {
1037                         int nxtsect = 0;
1038                         int nxt_clust = 0;
1039
1040                         nxt_clust = get_fatent(mydata, root_cluster);
1041                         fat32_end = CHECK_CLUST(nxt_clust, 32);
1042
1043                         nxtsect = mydata->data_begin +
1044                                 (nxt_clust * mydata->clust_size);
1045
1046                         root_cluster = nxt_clust;
1047
1048                         cursect = nxtsect;
1049                         j = 0;
1050                 } else {
1051                         cursect++;
1052                 }
1053
1054                 /* If end of rootdir reached */
1055                 if ((mydata->fatsize == 32 && fat32_end) ||
1056                     (mydata->fatsize != 32 && j == rootdir_size)) {
1057                         if (dols == LS_ROOT) {
1058                                 printf("\n%d file(s), %d dir(s)\n\n",
1059                                        files, dirs);
1060                                 ret = 0;
1061                         }
1062                         goto exit;
1063                 }
1064         }
1065 rootdir_done:
1066
1067         firsttime = 1;
1068
1069         while (isdir) {
1070                 int startsect = mydata->data_begin
1071                         + START(dentptr) * mydata->clust_size;
1072                 dir_entry dent;
1073                 char *nextname = NULL;
1074
1075                 dent = *dentptr;
1076                 dentptr = &dent;
1077
1078                 idx = dirdelim(subname);
1079
1080                 if (idx >= 0) {
1081                         subname[idx] = '\0';
1082                         nextname = subname + idx + 1;
1083                         /* Handle multiple delimiters */
1084                         while (ISDIRDELIM(*nextname))
1085                                 nextname++;
1086                         if (dols && *nextname == '\0')
1087                                 firsttime = 0;
1088                 } else {
1089                         if (dols && firsttime) {
1090                                 firsttime = 0;
1091                         } else {
1092                                 isdir = 0;
1093                         }
1094                 }
1095
1096                 if (get_dentfromdir(mydata, startsect, subname, dentptr,
1097                                      isdir ? 0 : dols) == NULL) {
1098                         if (dols && !isdir)
1099                                 ret = 0;
1100                         goto exit;
1101                 }
1102
1103                 if (idx >= 0) {
1104                         if (!(dentptr->attr & ATTR_DIR))
1105                                 goto exit;
1106                         subname = nextname;
1107                 }
1108         }
1109
1110         ret = get_contents(mydata, dentptr, buffer, maxsize);
1111         debug("Size: %d, got: %ld\n", FAT2CPU32(dentptr->size), ret);
1112
1113 exit:
1114         free(mydata->fatbuf);
1115         return ret;
1116 }
1117
1118 int file_fat_detectfs (void)
1119 {
1120         boot_sector bs;
1121         volume_info volinfo;
1122         int fatsize;
1123         char vol_label[12];
1124
1125         if (cur_dev == NULL) {
1126                 printf("No current device\n");
1127                 return 1;
1128         }
1129
1130 #if defined(CONFIG_CMD_IDE) || \
1131     defined(CONFIG_CMD_MG_DISK) || \
1132     defined(CONFIG_CMD_SATA) || \
1133     defined(CONFIG_CMD_SCSI) || \
1134     defined(CONFIG_CMD_USB) || \
1135     defined(CONFIG_MMC)
1136         printf("Interface:  ");
1137         switch (cur_dev->if_type) {
1138         case IF_TYPE_IDE:
1139                 printf("IDE");
1140                 break;
1141         case IF_TYPE_SATA:
1142                 printf("SATA");
1143                 break;
1144         case IF_TYPE_SCSI:
1145                 printf("SCSI");
1146                 break;
1147         case IF_TYPE_ATAPI:
1148                 printf("ATAPI");
1149                 break;
1150         case IF_TYPE_USB:
1151                 printf("USB");
1152                 break;
1153         case IF_TYPE_DOC:
1154                 printf("DOC");
1155                 break;
1156         case IF_TYPE_MMC:
1157                 printf("MMC");
1158                 break;
1159         default:
1160                 printf("Unknown");
1161         }
1162
1163         printf("\n  Device %d: ", cur_dev->dev);
1164         dev_print(cur_dev);
1165 #endif
1166
1167         if (read_bootsectandvi(&bs, &volinfo, &fatsize)) {
1168                 printf("\nNo valid FAT fs found\n");
1169                 return 1;
1170         }
1171
1172         memcpy(vol_label, volinfo.volume_label, 11);
1173         vol_label[11] = '\0';
1174         volinfo.fs_type[5] = '\0';
1175
1176         printf("Partition %d: Filesystem: %s \"%s\"\n", cur_part_nr,
1177                 volinfo.fs_type, vol_label);
1178
1179         return 0;
1180 }
1181
1182 int file_fat_ls (const char *dir)
1183 {
1184         return do_fat_read(dir, NULL, 0, LS_YES);
1185 }
1186
1187 long file_fat_read (const char *filename, void *buffer, unsigned long maxsize)
1188 {
1189         printf("reading %s\n", filename);
1190         return do_fat_read(filename, buffer, maxsize, LS_NO);
1191 }