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_SATA) || \
  74      defined(CONFIG_CMD_SCSI) || \
  75      defined(CONFIG_CMD_USB) || \
  76      defined(CONFIG_MMC) || \
  77      defined(CONFIG_SYSTEMACE) )
  78
  79         /* Read the partition table, if present */
  80         if (!get_partition_info(dev_desc, part_no, &cur_part_info)) {
  81                 cur_dev = dev_desc;
  82                 cur_part_nr = part_no;
  83         }
  84 #endif
  85
  86         /* Otherwise it might be a superfloppy (whole-disk FAT filesystem) */
  87         if (!cur_dev) {
  88                 if (part_no != 1) {
  89                         printf("** Partition %d not valid on device %d **\n",
  90                                         part_no, dev_desc->dev);
  91                         return -1;
  92                 }
  93
  94                 cur_dev = dev_desc;
  95                 cur_part_nr = 1;
  96                 cur_part_info.start = 0;
  97                 cur_part_info.size = dev_desc->lba;
  98                 cur_part_info.blksz = dev_desc->blksz;
  99                 memset(cur_part_info.name, 0, sizeof(cur_part_info.name));
 100                 memset(cur_part_info.type, 0, sizeof(cur_part_info.type));
 101         }
 102
 103         /* Make sure it has a valid FAT header */
 104         if (disk_read(0, 1, buffer) != 1) {
 105                 cur_dev = NULL;
 106                 return -1;
 107         }
 108
 109         /* Check if it's actually a DOS volume */
 110         if (memcmp(buffer + DOS_BOOT_MAGIC_OFFSET, "\x55\xAA", 2)) {
 111                 cur_dev = NULL;
 112                 return -1;
 113         }
 114
 115         /* Check for FAT12/FAT16/FAT32 filesystem */
 116         if (!memcmp(buffer + DOS_FS_TYPE_OFFSET, "FAT", 3))
 117                 return 0;
 118         if (!memcmp(buffer + DOS_FS32_TYPE_OFFSET, "FAT32", 5))
 119                 return 0;
 120
 121         cur_dev = NULL;
 122         return -1;
 123 }
 124
 125
 126 /*
 127  * Get the first occurence of a directory delimiter ('/' or '\') in a string.
 128  * Return index into string if found, -1 otherwise.
 129  */
 130 static int dirdelim (char *str)
 131 {
 132         char *start = str;
 133
 134         while (*str != '\0') {
 135                 if (ISDIRDELIM(*str))
 136                         return str - start;
 137                 str++;
 138         }
 139         return -1;
 140 }
 141
 142 /*
 143  * Extract zero terminated short name from a directory entry.
 144  */
 145 static void get_name (dir_entry *dirent, char *s_name)
 146 {
 147         char *ptr;
 148
 149         memcpy(s_name, dirent->name, 8);
 150         s_name[8] = '\0';
 151         ptr = s_name;
 152         while (*ptr && *ptr != ' ')
 153                 ptr++;
 154         if (dirent->ext[0] && dirent->ext[0] != ' ') {
 155                 *ptr = '.';
 156                 ptr++;
 157                 memcpy(ptr, dirent->ext, 3);
 158                 ptr[3] = '\0';
 159                 while (*ptr && *ptr != ' ')
 160                         ptr++;
 161         }
 162         *ptr = '\0';
 163         if (*s_name == DELETED_FLAG)
 164                 *s_name = '\0';
 165         else if (*s_name == aRING)
 166                 *s_name = DELETED_FLAG;
 167         downcase(s_name);
 168 }
 169
 170 /*
 171  * Get the entry at index 'entry' in a FAT (12/16/32) table.
 172  * On failure 0x00 is returned.
 173  */
 174 static __u32 get_fatent (fsdata *mydata, __u32 entry)
 175 {
 176         __u32 bufnum;
 177         __u32 off16, offset;
 178         __u32 ret = 0x00;
 179         __u16 val1, val2;
 180
 181         switch (mydata->fatsize) {
 182         case 32:
 183                 bufnum = entry / FAT32BUFSIZE;
 184                 offset = entry - bufnum * FAT32BUFSIZE;
 185                 break;
 186         case 16:
 187                 bufnum = entry / FAT16BUFSIZE;
 188                 offset = entry - bufnum * FAT16BUFSIZE;
 189                 break;
 190         case 12:
 191                 bufnum = entry / FAT12BUFSIZE;
 192                 offset = entry - bufnum * FAT12BUFSIZE;
 193                 break;
 194
 195         default:
 196                 /* Unsupported FAT size */
 197                 return ret;
 198         }
 199
 200         debug("FAT%d: entry: 0x%04x = %d, offset: 0x%04x = %d\n",
 201                mydata->fatsize, entry, entry, offset, offset);
 202
 203         /* Read a new block of FAT entries into the cache. */
 204         if (bufnum != mydata->fatbufnum) {
 205                 __u32 getsize = FATBUFBLOCKS;
 206                 __u8 *bufptr = mydata->fatbuf;
 207                 __u32 fatlength = mydata->fatlength;
 208                 __u32 startblock = bufnum * FATBUFBLOCKS;
 209
 210                 if (getsize > fatlength)
 211                         getsize = fatlength;
 212
 213                 fatlength *= mydata->sect_size; /* We want it in bytes now */
 214                 startblock += mydata->fat_sect; /* Offset from start of disk */
 215
 216                 if (disk_read(startblock, getsize, bufptr) < 0) {
 217                         debug("Error reading FAT blocks\n");
 218                         return ret;
 219                 }
 220                 mydata->fatbufnum = bufnum;
 221         }
 222
 223         /* Get the actual entry from the table */
 224         switch (mydata->fatsize) {
 225         case 32:
 226                 ret = FAT2CPU32(((__u32 *) mydata->fatbuf)[offset]);
 227                 break;
 228         case 16:
 229                 ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[offset]);
 230                 break;
 231         case 12:
 232                 off16 = (offset * 3) / 4;
 233
 234                 switch (offset & 0x3) {
 235                 case 0:
 236                         ret = FAT2CPU16(((__u16 *) mydata->fatbuf)[off16]);
 237                         ret &= 0xfff;
 238                         break;
 239                 case 1:
 240                         val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 241                         val1 &= 0xf000;
 242                         val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
 243                         val2 &= 0x00ff;
 244                         ret = (val2 << 4) | (val1 >> 12);
 245                         break;
 246                 case 2:
 247                         val1 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 248                         val1 &= 0xff00;
 249                         val2 = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16 + 1]);
 250                         val2 &= 0x000f;
 251                         ret = (val2 << 8) | (val1 >> 8);
 252                         break;
 253                 case 3:
 254                         ret = FAT2CPU16(((__u16 *)mydata->fatbuf)[off16]);
 255                         ret = (ret & 0xfff0) >> 4;
 256                         break;
 257                 default:
 258                         break;
 259                 }
 260                 break;
 261         }
 262         debug("FAT%d: ret: %08x, offset: %04x\n",
 263                mydata->fatsize, ret, offset);
 264
 265         return ret;
 266 }
 267
 268 /*
 269  * Read at most 'size' bytes from the specified cluster into 'buffer'.
 270  * Return 0 on success, -1 otherwise.
 271  */
 272 static int
 273 get_cluster (fsdata *mydata, __u32 clustnum, __u8 *buffer,
 274              unsigned long size)
 275 {
 276         __u32 idx = 0;
 277         __u32 startsect;
 278         __u32 nr_sect;
 279         int ret;
 280
 281         if (clustnum > 0) {
 282                 startsect = mydata->data_begin +
 283                                 clustnum * mydata->clust_size;
 284         } else {
 285                 startsect = mydata->rootdir_sect;
 286         }
 287
 288         debug("gc - clustnum: %d, startsect: %d\n", clustnum, startsect);
 289
 290         nr_sect = size / mydata->sect_size;
 291         ret = disk_read(startsect, nr_sect, buffer);
 292         if (ret != nr_sect) {
 293                 debug("Error reading data (got %d)\n", ret);
 294                 return -1;
 295         }
 296         if (size % mydata->sect_size) {
 297                 ALLOC_CACHE_ALIGN_BUFFER(__u8, tmpbuf, mydata->sect_size);
 298
 299                 idx = size / mydata->sect_size;
 300                 ret = disk_read(startsect + idx, 1, tmpbuf);
 301                 if (ret != 1) {
 302                         debug("Error reading data (got %d)\n", ret);
 303                         return -1;
 304                 }
 305                 buffer += idx * mydata->sect_size;
 306
 307                 memcpy(buffer, tmpbuf, size % mydata->sect_size);
 308                 return 0;
 309         }
 310
 311         return 0;
 312 }
 313
 314 /*
 315  * Read at most 'maxsize' bytes from the file associated with 'dentptr'
 316  * into 'buffer'.
 317  * Return the number of bytes read or -1 on fatal errors.
 318  */
 319 static long
 320 get_contents (fsdata *mydata, dir_entry *dentptr, __u8 *buffer,
 321               unsigned long maxsize)
 322 {
 323         unsigned long filesize = FAT2CPU32(dentptr->size), gotsize = 0;
 324         unsigned int bytesperclust = mydata->clust_size * mydata->sect_size;
 325         __u32 curclust = START(dentptr);
 326         __u32 endclust, newclust;
 327         unsigned long actsize;
 328
 329         debug("Filesize: %ld bytes\n", filesize);
 330
 331         if (maxsize > 0 && filesize > maxsize)
 332                 filesize = maxsize;
 333
 334         debug("%ld bytes\n", filesize);
 335
 336         actsize = bytesperclust;
 337         endclust = curclust;
 338
 339         do {
 340                 /* search for consecutive clusters */
 341                 while (actsize < filesize) {
 342                         newclust = get_fatent(mydata, endclust);
 343                         if ((newclust - 1) != endclust)
 344                                 goto getit;
 345                         if (CHECK_CLUST(newclust, mydata->fatsize)) {
 346                                 debug("curclust: 0x%x\n", newclust);
 347                                 debug("Invalid FAT entry\n");
 348                                 return gotsize;
 349                         }
 350                         endclust = newclust;
 351                         actsize += bytesperclust;
 352                 }
 353
 354                 /* actsize >= file size */
 355                 actsize -= bytesperclust;
 356
 357                 /* get remaining clusters */
 358                 if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
 359                         printf("Error reading cluster\n");
 360                         return -1;
 361                 }
 362
 363                 /* get remaining bytes */
 364                 gotsize += (int)actsize;
 365                 filesize -= actsize;
 366                 buffer += actsize;
 367                 actsize = filesize;
 368                 if (get_cluster(mydata, endclust, buffer, (int)actsize) != 0) {
 369                         printf("Error reading cluster\n");
 370                         return -1;
 371                 }
 372                 gotsize += actsize;
 373                 return gotsize;
 374 getit:
 375                 if (get_cluster(mydata, curclust, buffer, (int)actsize) != 0) {
 376                         printf("Error reading cluster\n");
 377                         return -1;
 378                 }
 379                 gotsize += (int)actsize;
 380                 filesize -= actsize;
 381                 buffer += actsize;
 382
 383                 curclust = get_fatent(mydata, endclust);
 384                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 385                         debug("curclust: 0x%x\n", curclust);
 386                         printf("Invalid FAT entry\n");
 387                         return gotsize;
 388                 }
 389                 actsize = bytesperclust;
 390                 endclust = curclust;
 391         } while (1);
 392 }
 393
 394 #ifdef CONFIG_SUPPORT_VFAT
 395 /*
 396  * Extract the file name information from 'slotptr' into 'l_name',
 397  * starting at l_name[*idx].
 398  * Return 1 if terminator (zero byte) is found, 0 otherwise.
 399  */
 400 static int slot2str (dir_slot *slotptr, char *l_name, int *idx)
 401 {
 402         int j;
 403
 404         for (j = 0; j <= 8; j += 2) {
 405                 l_name[*idx] = slotptr->name0_4[j];
 406                 if (l_name[*idx] == 0x00)
 407                         return 1;
 408                 (*idx)++;
 409         }
 410         for (j = 0; j <= 10; j += 2) {
 411                 l_name[*idx] = slotptr->name5_10[j];
 412                 if (l_name[*idx] == 0x00)
 413                         return 1;
 414                 (*idx)++;
 415         }
 416         for (j = 0; j <= 2; j += 2) {
 417                 l_name[*idx] = slotptr->name11_12[j];
 418                 if (l_name[*idx] == 0x00)
 419                         return 1;
 420                 (*idx)++;
 421         }
 422
 423         return 0;
 424 }
 425
 426 /*
 427  * Extract the full long filename starting at 'retdent' (which is really
 428  * a slot) into 'l_name'. If successful also copy the real directory entry
 429  * into 'retdent'
 430  * Return 0 on success, -1 otherwise.
 431  */
 432 __u8 get_vfatname_block[MAX_CLUSTSIZE]
 433         __aligned(ARCH_DMA_MINALIGN);
 434
 435 static int
 436 get_vfatname (fsdata *mydata, int curclust, __u8 *cluster,
 437               dir_entry *retdent, char *l_name)
 438 {
 439         dir_entry *realdent;
 440         dir_slot *slotptr = (dir_slot *)retdent;
 441         __u8 *buflimit = cluster + mydata->sect_size * ((curclust == 0) ?
 442                                                         PREFETCH_BLOCKS :
 443                                                         mydata->clust_size);
 444         __u8 counter = (slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff;
 445         int idx = 0;
 446
 447         if (counter > VFAT_MAXSEQ) {
 448                 debug("Error: VFAT name is too long\n");
 449                 return -1;
 450         }
 451
 452         while ((__u8 *)slotptr < buflimit) {
 453                 if (counter == 0)
 454                         break;
 455                 if (((slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff) != counter)
 456                         return -1;
 457                 slotptr++;
 458                 counter--;
 459         }
 460
 461         if ((__u8 *)slotptr >= buflimit) {
 462                 dir_slot *slotptr2;
 463
 464                 if (curclust == 0)
 465                         return -1;
 466                 curclust = get_fatent(mydata, curclust);
 467                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 468                         debug("curclust: 0x%x\n", curclust);
 469                         printf("Invalid FAT entry\n");
 470                         return -1;
 471                 }
 472
 473                 if (get_cluster(mydata, curclust, get_vfatname_block,
 474                                 mydata->clust_size * mydata->sect_size) != 0) {
 475                         debug("Error: reading directory block\n");
 476                         return -1;
 477                 }
 478
 479                 slotptr2 = (dir_slot *)get_vfatname_block;
 480                 while (counter > 0) {
 481                         if (((slotptr2->id & ~LAST_LONG_ENTRY_MASK)
 482                             & 0xff) != counter)
 483                                 return -1;
 484                         slotptr2++;
 485                         counter--;
 486                 }
 487
 488                 /* Save the real directory entry */
 489                 realdent = (dir_entry *)slotptr2;
 490                 while ((__u8 *)slotptr2 > get_vfatname_block) {
 491                         slotptr2--;
 492                         slot2str(slotptr2, l_name, &idx);
 493                 }
 494         } else {
 495                 /* Save the real directory entry */
 496                 realdent = (dir_entry *)slotptr;
 497         }
 498
 499         do {
 500                 slotptr--;
 501                 if (slot2str(slotptr, l_name, &idx))
 502                         break;
 503         } while (!(slotptr->id & LAST_LONG_ENTRY_MASK));
 504
 505         l_name[idx] = '\0';
 506         if (*l_name == DELETED_FLAG)
 507                 *l_name = '\0';
 508         else if (*l_name == aRING)
 509                 *l_name = DELETED_FLAG;
 510         downcase(l_name);
 511
 512         /* Return the real directory entry */
 513         memcpy(retdent, realdent, sizeof(dir_entry));
 514
 515         return 0;
 516 }
 517
 518 /* Calculate short name checksum */
 519 static __u8 mkcksum (const char *str)
 520 {
 521         int i;
 522
 523         __u8 ret = 0;
 524
 525         for (i = 0; i < 11; i++) {
 526                 ret = (((ret & 1) << 7) | ((ret & 0xfe) >> 1)) + str[i];
 527         }
 528
 529         return ret;
 530 }
 531 #endif  /* CONFIG_SUPPORT_VFAT */
 532
 533 /*
 534  * Get the directory entry associated with 'filename' from the directory
 535  * starting at 'startsect'
 536  */
 537 __u8 get_dentfromdir_block[MAX_CLUSTSIZE]
 538         __aligned(ARCH_DMA_MINALIGN);
 539
 540 static dir_entry *get_dentfromdir (fsdata *mydata, int startsect,
 541                                    char *filename, dir_entry *retdent,
 542                                    int dols)
 543 {
 544         __u16 prevcksum = 0xffff;
 545         __u32 curclust = START(retdent);
 546         int files = 0, dirs = 0;
 547
 548         debug("get_dentfromdir: %s\n", filename);
 549
 550         while (1) {
 551                 dir_entry *dentptr;
 552
 553                 int i;
 554
 555                 if (get_cluster(mydata, curclust, get_dentfromdir_block,
 556                                 mydata->clust_size * mydata->sect_size) != 0) {
 557                         debug("Error: reading directory block\n");
 558                         return NULL;
 559                 }
 560
 561                 dentptr = (dir_entry *)get_dentfromdir_block;
 562
 563                 for (i = 0; i < DIRENTSPERCLUST; i++) {
 564                         char s_name[14], l_name[VFAT_MAXLEN_BYTES];
 565
 566                         l_name[0] = '\0';
 567                         if (dentptr->name[0] == DELETED_FLAG) {
 568                                 dentptr++;
 569                                 continue;
 570                         }
 571                         if ((dentptr->attr & ATTR_VOLUME)) {
 572 #ifdef CONFIG_SUPPORT_VFAT
 573                                 if ((dentptr->attr & ATTR_VFAT) == ATTR_VFAT &&
 574                                     (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
 575                                         prevcksum = ((dir_slot *)dentptr)->alias_checksum;
 576                                         get_vfatname(mydata, curclust,
 577                                                      get_dentfromdir_block,
 578                                                      dentptr, l_name);
 579                                         if (dols) {
 580                                                 int isdir;
 581                                                 char dirc;
 582                                                 int doit = 0;
 583
 584                                                 isdir = (dentptr->attr & ATTR_DIR);
 585
 586                                                 if (isdir) {
 587                                                         dirs++;
 588                                                         dirc = '/';
 589                                                         doit = 1;
 590                                                 } else {
 591                                                         dirc = ' ';
 592                                                         if (l_name[0] != 0) {
 593                                                                 files++;
 594                                                                 doit = 1;
 595                                                         }
 596                                                 }
 597                                                 if (doit) {
 598                                                         if (dirc == ' ') {
 599                                                                 printf(" %8ld   %s%c\n",
 600                                                                         (long)FAT2CPU32(dentptr->size),
 601                                                                         l_name,
 602                                                                         dirc);
 603                                                         } else {
 604                                                                 printf("            %s%c\n",
 605                                                                         l_name,
 606                                                                         dirc);
 607                                                         }
 608                                                 }
 609                                                 dentptr++;
 610                                                 continue;
 611                                         }
 612                                         debug("vfatname: |%s|\n", l_name);
 613                                 } else
 614 #endif
 615                                 {
 616                                         /* Volume label or VFAT entry */
 617                                         dentptr++;
 618                                         continue;
 619                                 }
 620                         }
 621                         if (dentptr->name[0] == 0) {
 622                                 if (dols) {
 623                                         printf("\n%d file(s), %d dir(s)\n\n",
 624                                                 files, dirs);
 625                                 }
 626                                 debug("Dentname == NULL - %d\n", i);
 627                                 return NULL;
 628                         }
 629 #ifdef CONFIG_SUPPORT_VFAT
 630                         if (dols && mkcksum(dentptr->name) == prevcksum) {
 631                                 prevcksum = 0xffff;
 632                                 dentptr++;
 633                                 continue;
 634                         }
 635 #endif
 636                         get_name(dentptr, s_name);
 637                         if (dols) {
 638                                 int isdir = (dentptr->attr & ATTR_DIR);
 639                                 char dirc;
 640                                 int doit = 0;
 641
 642                                 if (isdir) {
 643                                         dirs++;
 644                                         dirc = '/';
 645                                         doit = 1;
 646                                 } else {
 647                                         dirc = ' ';
 648                                         if (s_name[0] != 0) {
 649                                                 files++;
 650                                                 doit = 1;
 651                                         }
 652                                 }
 653
 654                                 if (doit) {
 655                                         if (dirc == ' ') {
 656                                                 printf(" %8ld   %s%c\n",
 657                                                         (long)FAT2CPU32(dentptr->size),
 658                                                         s_name, dirc);
 659                                         } else {
 660                                                 printf("            %s%c\n",
 661                                                         s_name, dirc);
 662                                         }
 663                                 }
 664
 665                                 dentptr++;
 666                                 continue;
 667                         }
 668
 669                         if (strcmp(filename, s_name)
 670                             && strcmp(filename, l_name)) {
 671                                 debug("Mismatch: |%s|%s|\n", s_name, l_name);
 672                                 dentptr++;
 673                                 continue;
 674                         }
 675
 676                         memcpy(retdent, dentptr, sizeof(dir_entry));
 677
 678                         debug("DentName: %s", s_name);
 679                         debug(", start: 0x%x", START(dentptr));
 680                         debug(", size:  0x%x %s\n",
 681                               FAT2CPU32(dentptr->size),
 682                               (dentptr->attr & ATTR_DIR) ? "(DIR)" : "");
 683
 684                         return retdent;
 685                 }
 686
 687                 curclust = get_fatent(mydata, curclust);
 688                 if (CHECK_CLUST(curclust, mydata->fatsize)) {
 689                         debug("curclust: 0x%x\n", curclust);
 690                         printf("Invalid FAT entry\n");
 691                         return NULL;
 692                 }
 693         }
 694
 695         return NULL;
 696 }
 697
 698 /*
 699  * Read boot sector and volume info from a FAT filesystem
 700  */
 701 static int
 702 read_bootsectandvi (boot_sector *bs, volume_info *volinfo, int *fatsize)
 703 {
 704         __u8 *block;
 705         volume_info *vistart;
 706         int ret = 0;
 707
 708         if (cur_dev == NULL) {
 709                 debug("Error: no device selected\n");
 710                 return -1;
 711         }
 712
 713         block = memalign(ARCH_DMA_MINALIGN, cur_dev->blksz);
 714         if (block == NULL) {
 715                 debug("Error: allocating block\n");
 716                 return -1;
 717         }
 718
 719         if (disk_read (0, 1, block) < 0) {
 720                 debug("Error: reading block\n");
 721                 goto fail;
 722         }
 723
 724         memcpy(bs, block, sizeof(boot_sector));
 725         bs->reserved = FAT2CPU16(bs->reserved);
 726         bs->fat_length = FAT2CPU16(bs->fat_length);
 727         bs->secs_track = FAT2CPU16(bs->secs_track);
 728         bs->heads = FAT2CPU16(bs->heads);
 729         bs->total_sect = FAT2CPU32(bs->total_sect);
 730
 731         /* FAT32 entries */
 732         if (bs->fat_length == 0) {
 733                 /* Assume FAT32 */
 734                 bs->fat32_length = FAT2CPU32(bs->fat32_length);
 735                 bs->flags = FAT2CPU16(bs->flags);
 736                 bs->root_cluster = FAT2CPU32(bs->root_cluster);
 737                 bs->info_sector = FAT2CPU16(bs->info_sector);
 738                 bs->backup_boot = FAT2CPU16(bs->backup_boot);
 739                 vistart = (volume_info *)(block + sizeof(boot_sector));
 740                 *fatsize = 32;
 741         } else {
 742                 vistart = (volume_info *)&(bs->fat32_length);
 743                 *fatsize = 0;
 744         }
 745         memcpy(volinfo, vistart, sizeof(volume_info));
 746
 747         if (*fatsize == 32) {
 748                 if (strncmp(FAT32_SIGN, vistart->fs_type, SIGNLEN) == 0)
 749                         goto exit;
 750         } else {
 751                 if (strncmp(FAT12_SIGN, vistart->fs_type, SIGNLEN) == 0) {
 752                         *fatsize = 12;
 753                         goto exit;
 754                 }
 755                 if (strncmp(FAT16_SIGN, vistart->fs_type, SIGNLEN) == 0) {
 756                         *fatsize = 16;
 757                         goto exit;
 758                 }
 759         }
 760
 761         debug("Error: broken fs_type sign\n");
 762 fail:
 763         ret = -1;
 764 exit:
 765         free(block);
 766         return ret;
 767 }
 768
 769 __u8 do_fat_read_block[MAX_CLUSTSIZE]
 770         __aligned(ARCH_DMA_MINALIGN);
 771
 772 long
 773 do_fat_read (const char *filename, void *buffer, unsigned long maxsize,
 774              int dols)
 775 {
 776         char fnamecopy[2048];
 777         boot_sector bs;
 778         volume_info volinfo;
 779         fsdata datablock;
 780         fsdata *mydata = &datablock;
 781         dir_entry *dentptr;
 782         __u16 prevcksum = 0xffff;
 783         char *subname = "";
 784         __u32 cursect;
 785         int idx, isdir = 0;
 786         int files = 0, dirs = 0;
 787         long ret = -1;
 788         int firsttime;
 789         __u32 root_cluster = 0;
 790         int rootdir_size = 0;
 791         int j;
 792
 793         if (read_bootsectandvi(&bs, &volinfo, &mydata->fatsize)) {
 794                 debug("Error: reading boot sector\n");
 795                 return -1;
 796         }
 797
 798         if (mydata->fatsize == 32) {
 799                 root_cluster = bs.root_cluster;
 800                 mydata->fatlength = bs.fat32_length;
 801         } else {
 802                 mydata->fatlength = bs.fat_length;
 803         }
 804
 805         mydata->fat_sect = bs.reserved;
 806
 807         cursect = mydata->rootdir_sect
 808                 = mydata->fat_sect + mydata->fatlength * bs.fats;
 809
 810         mydata->sect_size = (bs.sector_size[1] << 8) + bs.sector_size[0];
 811         mydata->clust_size = bs.cluster_size;
 812         if (mydata->sect_size != cur_part_info.blksz) {
 813                 printf("Error: FAT sector size mismatch (fs=%hu, dev=%lu)\n",
 814                                 mydata->sect_size, cur_part_info.blksz);
 815                 return -1;
 816         }
 817
 818         if (mydata->fatsize == 32) {
 819                 mydata->data_begin = mydata->rootdir_sect -
 820                                         (mydata->clust_size * 2);
 821         } else {
 822                 rootdir_size = ((bs.dir_entries[1]  * (int)256 +
 823                                  bs.dir_entries[0]) *
 824                                  sizeof(dir_entry)) /
 825                                  mydata->sect_size;
 826                 mydata->data_begin = mydata->rootdir_sect +
 827                                         rootdir_size -
 828                                         (mydata->clust_size * 2);
 829         }
 830
 831         mydata->fatbufnum = -1;
 832         mydata->fatbuf = memalign(ARCH_DMA_MINALIGN, FATBUFSIZE);
 833         if (mydata->fatbuf == NULL) {
 834                 debug("Error: allocating memory\n");
 835                 return -1;
 836         }
 837
 838 #ifdef CONFIG_SUPPORT_VFAT
 839         debug("VFAT Support enabled\n");
 840 #endif
 841         debug("FAT%d, fat_sect: %d, fatlength: %d\n",
 842                mydata->fatsize, mydata->fat_sect, mydata->fatlength);
 843         debug("Rootdir begins at cluster: %d, sector: %d, offset: %x\n"
 844                "Data begins at: %d\n",
 845                root_cluster,
 846                mydata->rootdir_sect,
 847                mydata->rootdir_sect * mydata->sect_size, mydata->data_begin);
 848         debug("Sector size: %d, cluster size: %d\n", mydata->sect_size,
 849               mydata->clust_size);
 850
 851         /* "cwd" is always the root... */
 852         while (ISDIRDELIM(*filename))
 853                 filename++;
 854
 855         /* Make a copy of the filename and convert it to lowercase */
 856         strcpy(fnamecopy, filename);
 857         downcase(fnamecopy);
 858
 859         if (*fnamecopy == '\0') {
 860                 if (!dols)
 861                         goto exit;
 862
 863                 dols = LS_ROOT;
 864         } else if ((idx = dirdelim(fnamecopy)) >= 0) {
 865                 isdir = 1;
 866                 fnamecopy[idx] = '\0';
 867                 subname = fnamecopy + idx + 1;
 868
 869                 /* Handle multiple delimiters */
 870                 while (ISDIRDELIM(*subname))
 871                         subname++;
 872         } else if (dols) {
 873                 isdir = 1;
 874         }
 875
 876         j = 0;
 877         while (1) {
 878                 int i;
 879
 880                 debug("FAT read sect=%d, clust_size=%d, DIRENTSPERBLOCK=%zd\n",
 881                         cursect, mydata->clust_size, DIRENTSPERBLOCK);
 882
 883                 if (disk_read(cursect,
 884                                 (mydata->fatsize == 32) ?
 885                                 (mydata->clust_size) :
 886                                 PREFETCH_BLOCKS,
 887                                 do_fat_read_block) < 0) {
 888                         debug("Error: reading rootdir block\n");
 889                         goto exit;
 890                 }
 891
 892                 dentptr = (dir_entry *) do_fat_read_block;
 893
 894                 for (i = 0; i < DIRENTSPERBLOCK; i++) {
 895                         char s_name[14], l_name[VFAT_MAXLEN_BYTES];
 896
 897                         l_name[0] = '\0';
 898                         if (dentptr->name[0] == DELETED_FLAG) {
 899                                 dentptr++;
 900                                 continue;
 901                         }
 902                         if ((dentptr->attr & ATTR_VOLUME)) {
 903 #ifdef CONFIG_SUPPORT_VFAT
 904                                 if ((dentptr->attr & ATTR_VFAT) == ATTR_VFAT &&
 905                                     (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) {
 906                                         prevcksum =
 907                                                 ((dir_slot *)dentptr)->alias_checksum;
 908
 909                                         get_vfatname(mydata,
 910                                                      root_cluster,
 911                                                      do_fat_read_block,
 912                                                      dentptr, l_name);
 913
 914                                         if (dols == LS_ROOT) {
 915                                                 char dirc;
 916                                                 int doit = 0;
 917                                                 int isdir =
 918                                                         (dentptr->attr & ATTR_DIR);
 919
 920                                                 if (isdir) {
 921                                                         dirs++;
 922                                                         dirc = '/';
 923                                                         doit = 1;
 924                                                 } else {
 925                                                         dirc = ' ';
 926                                                         if (l_name[0] != 0) {
 927                                                                 files++;
 928                                                                 doit = 1;
 929                                                         }
 930                                                 }
 931                                                 if (doit) {
 932                                                         if (dirc == ' ') {
 933                                                                 printf(" %8ld   %s%c\n",
 934                                                                         (long)FAT2CPU32(dentptr->size),
 935                                                                         l_name,
 936                                                                         dirc);
 937                                                         } else {
 938                                                                 printf("            %s%c\n",
 939                                                                         l_name,
 940                                                                         dirc);
 941                                                         }
 942                                                 }
 943                                                 dentptr++;
 944                                                 continue;
 945                                         }
 946                                         debug("Rootvfatname: |%s|\n",
 947                                                l_name);
 948                                 } else
 949 #endif
 950                                 {
 951                                         /* Volume label or VFAT entry */
 952                                         dentptr++;
 953                                         continue;
 954                                 }
 955                         } else if (dentptr->name[0] == 0) {
 956                                 debug("RootDentname == NULL - %d\n", i);
 957                                 if (dols == LS_ROOT) {
 958                                         printf("\n%d file(s), %d dir(s)\n\n",
 959                                                 files, dirs);
 960                                         ret = 0;
 961                                 }
 962                                 goto exit;
 963                         }
 964 #ifdef CONFIG_SUPPORT_VFAT
 965                         else if (dols == LS_ROOT &&
 966                                  mkcksum(dentptr->name) == prevcksum) {
 967                                 prevcksum = 0xffff;
 968                                 dentptr++;
 969                                 continue;
 970                         }
 971 #endif
 972                         get_name(dentptr, s_name);
 973
 974                         if (dols == LS_ROOT) {
 975                                 int isdir = (dentptr->attr & ATTR_DIR);
 976                                 char dirc;
 977                                 int doit = 0;
 978
 979                                 if (isdir) {
 980                                         dirc = '/';
 981                                         if (s_name[0] != 0) {
 982                                                 dirs++;
 983                                                 doit = 1;
 984                                         }
 985                                 } else {
 986                                         dirc = ' ';
 987                                         if (s_name[0] != 0) {
 988                                                 files++;
 989                                                 doit = 1;
 990                                         }
 991                                 }
 992                                 if (doit) {
 993                                         if (dirc == ' ') {
 994                                                 printf(" %8ld   %s%c\n",
 995                                                         (long)FAT2CPU32(dentptr->size),
 996                                                         s_name, dirc);
 997                                         } else {
 998                                                 printf("            %s%c\n",
 999                                                         s_name, dirc);
1000                                         }
1001                                 }
1002                                 dentptr++;
1003                                 continue;
1004                         }
1005
1006                         if (strcmp(fnamecopy, s_name)
1007                             && strcmp(fnamecopy, l_name)) {
1008                                 debug("RootMismatch: |%s|%s|\n", s_name,
1009                                        l_name);
1010                                 dentptr++;
1011                                 continue;
1012                         }
1013
1014                         if (isdir && !(dentptr->attr & ATTR_DIR))
1015                                 goto exit;
1016
1017                         debug("RootName: %s", s_name);
1018                         debug(", start: 0x%x", START(dentptr));
1019                         debug(", size:  0x%x %s\n",
1020                                FAT2CPU32(dentptr->size),
1021                                isdir ? "(DIR)" : "");
1022
1023                         goto rootdir_done;      /* We got a match */
1024                 }
1025                 debug("END LOOP: j=%d   clust_size=%d\n", j,
1026                        mydata->clust_size);
1027
1028                 /*
1029                  * On FAT32 we must fetch the FAT entries for the next
1030                  * root directory clusters when a cluster has been
1031                  * completely processed.
1032                  */
1033                 ++j;
1034                 int fat32_end = 0;
1035                 if ((mydata->fatsize == 32) && (j == mydata->clust_size)) {
1036                         int nxtsect = 0;
1037                         int nxt_clust = 0;
1038
1039                         nxt_clust = get_fatent(mydata, root_cluster);
1040                         fat32_end = CHECK_CLUST(nxt_clust, 32);
1041
1042                         nxtsect = mydata->data_begin +
1043                                 (nxt_clust * mydata->clust_size);
1044
1045                         root_cluster = nxt_clust;
1046
1047                         cursect = nxtsect;
1048                         j = 0;
1049                 } else {
1050                         cursect++;
1051                 }
1052
1053                 /* If end of rootdir reached */
1054                 if ((mydata->fatsize == 32 && fat32_end) ||
1055                     (mydata->fatsize != 32 && j == rootdir_size)) {
1056                         if (dols == LS_ROOT) {
1057                                 printf("\n%d file(s), %d dir(s)\n\n",
1058                                        files, dirs);
1059                                 ret = 0;
1060                         }
1061                         goto exit;
1062                 }
1063         }
1064 rootdir_done:
1065
1066         firsttime = 1;
1067
1068         while (isdir) {
1069                 int startsect = mydata->data_begin
1070                         + START(dentptr) * mydata->clust_size;
1071                 dir_entry dent;
1072                 char *nextname = NULL;
1073
1074                 dent = *dentptr;
1075                 dentptr = &dent;
1076
1077                 idx = dirdelim(subname);
1078
1079                 if (idx >= 0) {
1080                         subname[idx] = '\0';
1081                         nextname = subname + idx + 1;
1082                         /* Handle multiple delimiters */
1083                         while (ISDIRDELIM(*nextname))
1084                                 nextname++;
1085                         if (dols && *nextname == '\0')
1086                                 firsttime = 0;
1087                 } else {
1088                         if (dols && firsttime) {
1089                                 firsttime = 0;
1090                         } else {
1091                                 isdir = 0;
1092                         }
1093                 }
1094
1095                 if (get_dentfromdir(mydata, startsect, subname, dentptr,
1096                                      isdir ? 0 : dols) == NULL) {
1097                         if (dols && !isdir)
1098                                 ret = 0;
1099                         goto exit;
1100                 }
1101
1102                 if (idx >= 0) {
1103                         if (!(dentptr->attr & ATTR_DIR))
1104                                 goto exit;
1105                         subname = nextname;
1106                 }
1107         }
1108
1109         ret = get_contents(mydata, dentptr, buffer, maxsize);
1110         debug("Size: %d, got: %ld\n", FAT2CPU32(dentptr->size), ret);
1111
1112 exit:
1113         free(mydata->fatbuf);
1114         return ret;
1115 }
1116
1117 int file_fat_detectfs (void)
1118 {
1119         boot_sector bs;
1120         volume_info volinfo;
1121         int fatsize;
1122         char vol_label[12];
1123
1124         if (cur_dev == NULL) {
1125                 printf("No current device\n");
1126                 return 1;
1127         }
1128
1129 #if defined(CONFIG_CMD_IDE) || \
1130     defined(CONFIG_CMD_SATA) || \
1131     defined(CONFIG_CMD_SCSI) || \
1132     defined(CONFIG_CMD_USB) || \
1133     defined(CONFIG_MMC)
1134         printf("Interface:  ");
1135         switch (cur_dev->if_type) {
1136         case IF_TYPE_IDE:
1137                 printf("IDE");
1138                 break;
1139         case IF_TYPE_SATA:
1140                 printf("SATA");
1141                 break;
1142         case IF_TYPE_SCSI:
1143                 printf("SCSI");
1144                 break;
1145         case IF_TYPE_ATAPI:
1146                 printf("ATAPI");
1147                 break;
1148         case IF_TYPE_USB:
1149                 printf("USB");
1150                 break;
1151         case IF_TYPE_DOC:
1152                 printf("DOC");
1153                 break;
1154         case IF_TYPE_MMC:
1155                 printf("MMC");
1156                 break;
1157         default:
1158                 printf("Unknown");
1159         }
1160
1161         printf("\n  Device %d: ", cur_dev->dev);
1162         dev_print(cur_dev);
1163 #endif
1164
1165         if (read_bootsectandvi(&bs, &volinfo, &fatsize)) {
1166                 printf("\nNo valid FAT fs found\n");
1167                 return 1;
1168         }
1169
1170         memcpy(vol_label, volinfo.volume_label, 11);
1171         vol_label[11] = '\0';
1172         volinfo.fs_type[5] = '\0';
1173
1174         printf("Partition %d: Filesystem: %s \"%s\"\n", cur_part_nr,
1175                 volinfo.fs_type, vol_label);
1176
1177         return 0;
1178 }
1179
1180 int file_fat_ls (const char *dir)
1181 {
1182         return do_fat_read(dir, NULL, 0, LS_YES);
1183 }
1184
1185 long file_fat_read (const char *filename, void *buffer, unsigned long maxsize)
1186 {
1187         printf("reading %s\n", filename);
1188         return do_fat_read(filename, buffer, maxsize, LS_NO);
1189 }