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