| 1 | /*===============================================================*\ |
| 2 | | Project: RTEMS msdos format functionality | |
| 3 | +-----------------------------------------------------------------+ |
| 4 | | File: msdos_format.c | |
| 5 | +-----------------------------------------------------------------+ |
| 6 | | Copyright (c) 2004 IMD | |
| 7 | | Ingenieurbuero fuer Microcomputertechnik Th. Doerfler | |
| 8 | | <Thomas.Doerfler@imd-systems.de> | |
| 9 | | all rights reserved | |
| 10 | +-----------------------------------------------------------------+ |
| 11 | | this file contains msdos_format function. This function | |
| 12 | | formats a disk partition conforming to MS-DOS conventions | |
| 13 | | | |
| 14 | | The license and distribution terms for this file may be | |
| 15 | | found in the file LICENSE in this distribution or at | |
| 16 | | http://www.rtems.com/license/LICENSE. | |
| 17 | | | |
| 18 | +-----------------------------------------------------------------+ |
| 19 | | date history ID | |
| 20 | | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ | |
| 21 | | 29.10.04 creation doe | |
| 22 | \*===============================================================*/ |
| 23 | |
| 24 | #if HAVE_CONFIG_H |
| 25 | #include "config.h" |
| 26 | #endif |
| 27 | |
| 28 | #include <sys/types.h> |
| 29 | #include <sys/stat.h> |
| 30 | #include <fcntl.h> |
| 31 | #include <unistd.h> |
| 32 | #include <errno.h> |
| 33 | #include <stdlib.h> |
| 34 | #include <ctype.h> |
| 35 | #include <assert.h> |
| 36 | |
| 37 | #include <rtems/libio_.h> |
| 38 | |
| 39 | #include "fat.h" |
| 40 | #include "fat_fat_operations.h" |
| 41 | #include "msdos.h" |
| 42 | #include "dosfs.h" |
| 43 | |
| 44 | typedef struct { |
| 45 | unsigned32 bytes_per_sector; |
| 46 | unsigned32 totl_sector_cnt; |
| 47 | unsigned32 rsvd_sector_cnt; |
| 48 | |
| 49 | unsigned32 sectors_per_cluster; |
| 50 | unsigned32 sectors_per_fat; |
| 51 | |
| 52 | unsigned32 fat_start_sec; |
| 53 | unsigned32 files_per_root_dir; |
| 54 | unsigned32 root_dir_sectors; |
| 55 | unsigned32 root_dir_start_sec; |
| 56 | unsigned32 root_dir_fmt_sec_cnt; |
| 57 | unsigned32 mbr_copy_sec; /* location of copy of mbr or 0 */ |
| 58 | unsigned32 fsinfo_sec; /* location of fsinfo sector or 0 */ |
| 59 | unsigned8 fat_num; |
| 60 | unsigned8 media_code; |
| 61 | unsigned8 fattype; |
| 62 | char OEMName[FAT_BR_OEMNAME_SIZE+1]; |
| 63 | char VolLabel[FAT_BR_VOLLAB_SIZE+1]; |
| 64 | boolean VolLabel_present; |
| 65 | unsigned32 vol_id; |
| 66 | } msdos_format_param_t; |
| 67 | |
| 68 | /*=========================================================================*\ |
| 69 | | Function: | |
| 70 | \*-------------------------------------------------------------------------*/ |
| 71 | static int msdos_format_write_sec |
| 72 | ( |
| 73 | /*-------------------------------------------------------------------------*\ |
| 74 | | Purpose: | |
| 75 | | function to write to a sector | |
| 76 | +---------------------------------------------------------------------------+ |
| 77 | | Input Parameters: | |
| 78 | \*-------------------------------------------------------------------------*/ |
| 79 | int fd, /* file descriptor index */ |
| 80 | unsigned32 start_sector, /* sector number to write to */ |
| 81 | unsigned32 sector_size, /* size of sector */ |
| 82 | const char *buffer /* buffer with write data */ |
| 83 | ) |
| 84 | /*-------------------------------------------------------------------------*\ |
| 85 | | Return Value: | |
| 86 | | 0, if success, -1 and errno if failed | |
| 87 | \*=========================================================================*/ |
| 88 | { |
| 89 | int ret_val = 0; |
| 90 | |
| 91 | if (0 > lseek(fd,((off_t)start_sector)*sector_size,SEEK_SET)) { |
| 92 | ret_val = -1; |
| 93 | } |
| 94 | if (ret_val == 0) { |
| 95 | if (0 > write(fd,buffer,sector_size)) { |
| 96 | ret_val = -1; |
| 97 | } |
| 98 | } |
| 99 | |
| 100 | return ret_val; |
| 101 | } |
| 102 | |
| 103 | /*=========================================================================*\ |
| 104 | | Function: | |
| 105 | \*-------------------------------------------------------------------------*/ |
| 106 | static int msdos_format_fill_sectors |
| 107 | ( |
| 108 | /*-------------------------------------------------------------------------*\ |
| 109 | | Purpose: | |
| 110 | | function to fill sectors with byte | |
| 111 | +---------------------------------------------------------------------------+ |
| 112 | | Input Parameters: | |
| 113 | \*-------------------------------------------------------------------------*/ |
| 114 | int fd, /* file descriptor index */ |
| 115 | unsigned32 start_sector, /* sector number to fill to */ |
| 116 | unsigned32 sector_cnt, /* number of sectors to fill to */ |
| 117 | unsigned32 sector_size, /* size of sector */ |
| 118 | const char fill_byte /* byte to fill into sectors */ |
| 119 | ) |
| 120 | /*-------------------------------------------------------------------------*\ |
| 121 | | Return Value: | |
| 122 | | 0, if success, -1 and errno if failed | |
| 123 | \*=========================================================================*/ |
| 124 | { |
| 125 | int ret_val = 0; |
| 126 | char *fill_buffer = NULL; |
| 127 | |
| 128 | /* |
| 129 | * allocate and fill buffer |
| 130 | */ |
| 131 | if (ret_val == 0) { |
| 132 | fill_buffer = malloc(sector_size); |
| 133 | if (fill_buffer == NULL) { |
| 134 | errno = ENOMEM; |
| 135 | ret_val = -1; |
| 136 | } |
| 137 | else { |
| 138 | memset(fill_buffer,fill_byte,sector_size); |
| 139 | } |
| 140 | } |
| 141 | /* |
| 142 | * write to consecutive sectors |
| 143 | */ |
| 144 | while ((ret_val == 0) && |
| 145 | (sector_cnt > 0)) { |
| 146 | ret_val = msdos_format_write_sec(fd,start_sector,sector_size,fill_buffer); |
| 147 | start_sector++; |
| 148 | sector_cnt--; |
| 149 | } |
| 150 | /* |
| 151 | * cleanup |
| 152 | */ |
| 153 | if (fill_buffer != NULL) { |
| 154 | free(fill_buffer); |
| 155 | fill_buffer = NULL; |
| 156 | } |
| 157 | return ret_val; |
| 158 | } |
| 159 | |
| 160 | |
| 161 | /*=========================================================================*\ |
| 162 | | Function: | |
| 163 | \*-------------------------------------------------------------------------*/ |
| 164 | static int msdos_format_gen_volid |
| 165 | ( |
| 166 | /*-------------------------------------------------------------------------*\ |
| 167 | | Purpose: | |
| 168 | | function to generate a pseudo-random volume id | |
| 169 | +---------------------------------------------------------------------------+ |
| 170 | | Input Parameters: | |
| 171 | \*-------------------------------------------------------------------------*/ |
| 172 | unsigned32 *volid_ptr /* volume ID return pointer */ |
| 173 | ) |
| 174 | /*-------------------------------------------------------------------------*\ |
| 175 | | Return Value: | |
| 176 | | 0, if success, -1 and errno if failed | |
| 177 | \*=========================================================================*/ |
| 178 | { |
| 179 | int ret_val = 0; |
| 180 | int rc; |
| 181 | rtems_clock_time_value time_value; |
| 182 | |
| 183 | rc = rtems_clock_get(RTEMS_CLOCK_GET_TIME_VALUE,&time_value); |
| 184 | if (rc == RTEMS_SUCCESSFUL) { |
| 185 | *volid_ptr = time_value.seconds + time_value.microseconds; |
| 186 | } |
| 187 | else { |
| 188 | *volid_ptr = rand(); |
| 189 | } |
| 190 | |
| 191 | return ret_val; |
| 192 | } |
| 193 | |
| 194 | |
| 195 | /*=========================================================================*\ |
| 196 | | Function: | |
| 197 | \*-------------------------------------------------------------------------*/ |
| 198 | static int msdos_format_eval_sectors_per_cluster |
| 199 | ( |
| 200 | /*-------------------------------------------------------------------------*\ |
| 201 | | Purpose: | |
| 202 | | function to check/adjust sectors_per_cluster to legal values | |
| 203 | +---------------------------------------------------------------------------+ |
| 204 | | Input Parameters: | |
| 205 | \*-------------------------------------------------------------------------*/ |
| 206 | int fattype, /* type code of FAT (FAT_FAT12 ...) */ |
| 207 | unsigned32 bytes_per_sector, /* byte count per sector (512) */ |
| 208 | unsigned32 fatdata_sec_cnt, /* sectors available for FAT and data */ |
| 209 | unsigned8 fat_num, /* number of fat copies */ |
| 210 | unsigned32 sectors_per_cluster, /* sectors per cluster (requested) */ |
| 211 | unsigned32 *sectors_per_cluster_adj, /* ret: sec per cluster (granted) */ |
| 212 | unsigned32 *sectors_per_fat_ptr /* ret: sectors needed for one FAT */ |
| 213 | ) |
| 214 | /*-------------------------------------------------------------------------*\ |
| 215 | | Return Value: | |
| 216 | | 0, if success, -1 and errno if failed | |
| 217 | \*=========================================================================*/ |
| 218 | { |
| 219 | |
| 220 | boolean finished = FALSE; |
| 221 | int ret_val = 0; |
| 222 | unsigned32 fatdata_cluster_cnt; |
| 223 | unsigned32 fat_capacity; |
| 224 | unsigned32 sectors_per_fat; |
| 225 | unsigned32 data_cluster_cnt; |
| 226 | /* |
| 227 | * ensure, that maximum cluster size (32KByte) is not exceeded |
| 228 | */ |
| 229 | while (MS_BYTES_PER_CLUSTER_LIMIT / bytes_per_sector < sectors_per_cluster) { |
| 230 | sectors_per_cluster /= 2; |
| 231 | } |
| 232 | |
| 233 | do { |
| 234 | /* |
| 235 | * compute number of data clusters for current data: |
| 236 | * - compute cluster count for data AND fat |
| 237 | * - compute storage size for FAT |
| 238 | * - subtract from total cluster count |
| 239 | */ |
| 240 | fatdata_cluster_cnt = fatdata_sec_cnt/sectors_per_cluster; |
| 241 | if (fattype == FAT_FAT12) { |
| 242 | fat_capacity = fatdata_cluster_cnt * 3 / 2; |
| 243 | } |
| 244 | else if (fattype == FAT_FAT16) { |
| 245 | fat_capacity = fatdata_cluster_cnt * 2; |
| 246 | } |
| 247 | else { /* FAT32 */ |
| 248 | fat_capacity = fatdata_cluster_cnt * 4; |
| 249 | } |
| 250 | |
| 251 | sectors_per_fat = ((fat_capacity |
| 252 | + (bytes_per_sector - 1)) |
| 253 | / bytes_per_sector); |
| 254 | |
| 255 | data_cluster_cnt = (fatdata_cluster_cnt - |
| 256 | (((sectors_per_fat * fat_num) |
| 257 | + (sectors_per_cluster - 1)) |
| 258 | / sectors_per_cluster)); |
| 259 | /* |
| 260 | * data cluster count too big? then make sectors bigger |
| 261 | */ |
| 262 | if (((fattype == FAT_FAT12) && (data_cluster_cnt > FAT_FAT12_MAX_CLN)) || |
| 263 | ((fattype == FAT_FAT16) && (data_cluster_cnt > FAT_FAT16_MAX_CLN))) { |
| 264 | sectors_per_cluster *= 2; |
| 265 | } |
| 266 | else { |
| 267 | finished = TRUE; |
| 268 | } |
| 269 | /* |
| 270 | * when maximum cluster size is exceeded, we have invalid data, abort... |
| 271 | */ |
| 272 | if ((sectors_per_cluster * bytes_per_sector) |
| 273 | > MS_BYTES_PER_CLUSTER_LIMIT) { |
| 274 | ret_val = EINVAL; |
| 275 | finished = TRUE; |
| 276 | } |
| 277 | } while (!finished); |
| 278 | |
| 279 | if (ret_val != 0) { |
| 280 | set_errno_and_return_minus_one(ret_val); |
| 281 | } |
| 282 | else { |
| 283 | *sectors_per_cluster_adj = sectors_per_cluster; |
| 284 | *sectors_per_fat_ptr = sectors_per_fat; |
| 285 | return 0; |
| 286 | } |
| 287 | } |
| 288 | |
| 289 | |
| 290 | /*=========================================================================*\ |
| 291 | | Function: | |
| 292 | \*-------------------------------------------------------------------------*/ |
| 293 | static int msdos_format_determine_fmt_params |
| 294 | ( |
| 295 | /*-------------------------------------------------------------------------*\ |
| 296 | | Purpose: | |
| 297 | | determine parameters for formatting | |
| 298 | +---------------------------------------------------------------------------+ |
| 299 | | Input Parameters: | |
| 300 | \*-------------------------------------------------------------------------*/ |
| 301 | const disk_device *dd, /* disk device structure */ |
| 302 | const msdos_format_request_param_t *rqdata, /* requested fmt parameters */ |
| 303 | msdos_format_param_t *fmt_params/* computed fmt parameters */ |
| 304 | ) |
| 305 | /*-------------------------------------------------------------------------*\ |
| 306 | | Return Value: | |
| 307 | | 0, if success, -1 and errno if failed | |
| 308 | \*=========================================================================*/ |
| 309 | { |
| 310 | int ret_val = 0; |
| 311 | unsigned32 fatdata_sect_cnt; |
| 312 | unsigned32 onebit; |
| 313 | unsigned32 sectors_per_cluster_adj; |
| 314 | |
| 315 | memset(fmt_params,0,sizeof(*fmt_params)); |
| 316 | /* |
| 317 | * this one is fixed in this implementation. |
| 318 | * At least one thing we don't have to magically guess... |
| 319 | */ |
| 320 | if (ret_val == 0) { |
| 321 | fmt_params->bytes_per_sector = dd->block_size; |
| 322 | fmt_params->totl_sector_cnt = dd->size; |
| 323 | } |
| 324 | /* |
| 325 | * determine number of FATs |
| 326 | */ |
| 327 | if (ret_val == 0) { |
| 328 | if ((rqdata == NULL) || |
| 329 | (rqdata->fat_num == 0)) { |
| 330 | fmt_params->fat_num = 2; |
| 331 | } |
| 332 | else if (rqdata->fat_num <= 6) { |
| 333 | fmt_params->fat_num = rqdata->fat_num; |
| 334 | } |
| 335 | else { |
| 336 | ret_val = EINVAL; |
| 337 | } |
| 338 | } |
| 339 | /* |
| 340 | * Now we get sort of a loop when determining things: |
| 341 | * The FAT type (FAT12/16/32) is determined ONLY from the |
| 342 | * data cluster count: |
| 343 | * Disks with data cluster count < 4085 are FAT12. |
| 344 | * Disks with data cluster count < 65525 are FAT16. |
| 345 | * The rest is FAT32 (no FAT128 available yet :-) |
| 346 | * |
| 347 | * The number of data clusters is the |
| 348 | * total capacity |
| 349 | * minus reserved sectors |
| 350 | * minus root directory ares |
| 351 | * minus storage needed for the FAT (and its copy/copies). |
| 352 | * |
| 353 | * The last item once again depends on the FAT type and the cluster count. |
| 354 | * |
| 355 | * So here is what we do in this formatter: |
| 356 | * - If a FAT type is requested from the caller, we try to modify |
| 357 | * the cluster size, until the data cluster count is in range |
| 358 | * - If no FAT type is given, we estimate a useful FAT type from |
| 359 | * the disk capacity and then adapt the cluster size |
| 360 | */ |
| 361 | |
| 362 | /* |
| 363 | * determine characteristic values: |
| 364 | * - number of sectors |
| 365 | * - number of reserved sectors |
| 366 | * - number of used sectors |
| 367 | * - sectors per cluster |
| 368 | */ |
| 369 | /* |
| 370 | * determine FAT type and sectors per cluster |
| 371 | * depends on |
| 372 | */ |
| 373 | if (ret_val == 0) { |
| 374 | fmt_params->sectors_per_cluster = 1; |
| 375 | if ((rqdata != NULL) && |
| 376 | (rqdata->fattype == MSDOS_FMT_FAT12)) { |
| 377 | fmt_params->fattype = FAT_FAT12; |
| 378 | } |
| 379 | else if ((rqdata != NULL) && |
| 380 | (rqdata->fattype == MSDOS_FMT_FAT16)) { |
| 381 | fmt_params->fattype = FAT_FAT16; |
| 382 | } |
| 383 | else if ((rqdata != NULL) && |
| 384 | (rqdata->fattype == MSDOS_FMT_FAT32)) { |
| 385 | fmt_params->fattype = FAT_FAT32; |
| 386 | } |
| 387 | else if ((rqdata != NULL) && |
| 388 | (rqdata->fattype != MSDOS_FMT_FATANY)) { |
| 389 | ret_val = -1; |
| 390 | errno = EINVAL; |
| 391 | } |
| 392 | else { |
| 393 | /* |
| 394 | * limiting values for disk size, fat type, sectors per cluster |
| 395 | * NOTE: maximum sect_per_clust is arbitrarily choosen with values that |
| 396 | * are a compromise concerning capacity and efficency |
| 397 | */ |
| 398 | if (fmt_params->totl_sector_cnt |
| 399 | < ((unsigned32)FAT_FAT12_MAX_CLN)*8) { |
| 400 | fmt_params->fattype = FAT_FAT12; |
| 401 | /* start trying with small clusters */ |
| 402 | fmt_params->sectors_per_cluster = 2; |
| 403 | } |
| 404 | else if (fmt_params->totl_sector_cnt |
| 405 | < ((unsigned32)FAT_FAT16_MAX_CLN)*32) { |
| 406 | fmt_params->fattype = FAT_FAT16; |
| 407 | /* start trying with small clusters */ |
| 408 | fmt_params->sectors_per_cluster = 2; |
| 409 | } |
| 410 | else { |
| 411 | fmt_params->fattype = FAT_FAT32; |
| 412 | /* start trying with small clusters... */ |
| 413 | fmt_params->sectors_per_cluster = 1; |
| 414 | } |
| 415 | } |
| 416 | /* |
| 417 | * try to use user requested cluster size |
| 418 | */ |
| 419 | if ((rqdata != NULL) && |
| 420 | (rqdata->sectors_per_cluster > 0)) { |
| 421 | fmt_params->sectors_per_cluster = |
| 422 | rqdata->sectors_per_cluster; |
| 423 | } |
| 424 | /* |
| 425 | * check sectors per cluster. |
| 426 | * must be power of 2 |
| 427 | * must be smaller than or equal to 128 |
| 428 | * sectors_per_cluster*bytes_per_sector must not be bigger than 32K |
| 429 | */ |
| 430 | for (onebit = 128;onebit >= 1;onebit = onebit>>1) { |
| 431 | if (fmt_params->sectors_per_cluster > onebit) { |
| 432 | fmt_params->sectors_per_cluster = onebit; |
| 433 | if (fmt_params->sectors_per_cluster |
| 434 | <= 32768L/fmt_params->bytes_per_sector) { |
| 435 | /* value is small enough so this value is ok */ |
| 436 | onebit = 1; |
| 437 | } |
| 438 | } |
| 439 | } |
| 440 | } |
| 441 | |
| 442 | if (ret_val == 0) { |
| 443 | if (fmt_params->fattype == FAT_FAT32) { |
| 444 | /* recommended: for FAT32, always set reserved sector count to 32 */ |
| 445 | fmt_params->rsvd_sector_cnt = 32; |
| 446 | /* for FAT32, always set files per root directory 0 */ |
| 447 | fmt_params->files_per_root_dir = 0; |
| 448 | /* location of copy of MBR */ |
| 449 | fmt_params->mbr_copy_sec = 6; |
| 450 | /* location of fsinfo sector */ |
| 451 | fmt_params->fsinfo_sec = 1; |
| 452 | |
| 453 | } |
| 454 | else { |
| 455 | /* recommended: for FAT12/FAT16, always set reserved sector count to 1 */ |
| 456 | fmt_params->rsvd_sector_cnt = 1; |
| 457 | /* recommended: for FAT16, set files per root directory to 512 */ |
| 458 | /* for FAT12/FAT16, set files per root directory */ |
| 459 | /* must fill up an even count of sectors */ |
| 460 | if ((rqdata != NULL) && |
| 461 | (rqdata->files_per_root_dir > 0)) { |
| 462 | fmt_params->files_per_root_dir = rqdata->files_per_root_dir; |
| 463 | } |
| 464 | else { |
| 465 | if (fmt_params->fattype == FAT_FAT16) { |
| 466 | fmt_params->files_per_root_dir = 512; |
| 467 | } |
| 468 | else { |
| 469 | fmt_params->files_per_root_dir = 64; |
| 470 | } |
| 471 | } |
| 472 | fmt_params->files_per_root_dir = (fmt_params->files_per_root_dir + |
| 473 | (2*fmt_params->bytes_per_sector/ |
| 474 | FAT_DIRENTRY_SIZE-1)); |
| 475 | fmt_params->files_per_root_dir -= (fmt_params->files_per_root_dir % |
| 476 | (2*fmt_params->bytes_per_sector |
| 477 | /FAT_DIRENTRY_SIZE)); |
| 478 | } |
| 479 | fmt_params->root_dir_sectors = |
| 480 | (((fmt_params->files_per_root_dir * FAT_DIRENTRY_SIZE) |
| 481 | + fmt_params->bytes_per_sector - 1) |
| 482 | / fmt_params->bytes_per_sector); |
| 483 | } |
| 484 | if (ret_val == 0) { |
| 485 | fatdata_sect_cnt = (fmt_params->totl_sector_cnt - |
| 486 | fmt_params->rsvd_sector_cnt - |
| 487 | fmt_params->root_dir_sectors); |
| 488 | |
| 489 | /* |
| 490 | * check values to get legal arrangement of FAT type and cluster count |
| 491 | */ |
| 492 | |
| 493 | ret_val = msdos_format_eval_sectors_per_cluster |
| 494 | (fmt_params->fattype, |
| 495 | fmt_params->bytes_per_sector, |
| 496 | fatdata_sect_cnt, |
| 497 | fmt_params->fat_num, |
| 498 | fmt_params->sectors_per_cluster, |
| 499 | §ors_per_cluster_adj, |
| 500 | &(fmt_params->sectors_per_fat)); |
| 501 | fmt_params->sectors_per_cluster = sectors_per_cluster_adj; |
| 502 | } |
| 503 | |
| 504 | /* |
| 505 | * determine media code |
| 506 | */ |
| 507 | if (ret_val == 0) { |
| 508 | if ((rqdata != NULL) && |
| 509 | (rqdata->media != 0)) { |
| 510 | const char valid_media_codes[] = |
| 511 | {0xF0,0xF8,0xF9,0xFA,0xFB,0xFC,0xFD,0xFE,0xFF}; |
| 512 | if (NULL==memchr(valid_media_codes, |
| 513 | rqdata->media, |
| 514 | sizeof(valid_media_codes))) { |
| 515 | ret_val = -1; |
| 516 | errno = EINVAL; |
| 517 | } |
| 518 | else { |
| 519 | fmt_params->media_code = rqdata->media; |
| 520 | } |
| 521 | } |
| 522 | else { |
| 523 | fmt_params->media_code = FAT_BR_MEDIA_FIXED; |
| 524 | } |
| 525 | } |
| 526 | /* |
| 527 | * determine location and size of root directory |
| 528 | * for formatting |
| 529 | */ |
| 530 | if (fmt_params->root_dir_sectors > 0) { |
| 531 | fmt_params->root_dir_start_sec = |
| 532 | fmt_params->rsvd_sector_cnt |
| 533 | + (fmt_params-> fat_num*fmt_params->sectors_per_fat); |
| 534 | fmt_params->root_dir_fmt_sec_cnt = fmt_params->root_dir_sectors; |
| 535 | } |
| 536 | else { |
| 537 | /* |
| 538 | * for FAT32: root directory is in cluster 2 |
| 539 | */ |
| 540 | fmt_params->root_dir_start_sec = |
| 541 | fmt_params->rsvd_sector_cnt |
| 542 | + (fmt_params-> fat_num*fmt_params->sectors_per_fat); |
| 543 | fmt_params->root_dir_fmt_sec_cnt = fmt_params->sectors_per_cluster; |
| 544 | } |
| 545 | /* |
| 546 | * determine usable OEMName |
| 547 | */ |
| 548 | if (ret_val == 0) { |
| 549 | const char *from; |
| 550 | char *to = fmt_params->OEMName; |
| 551 | int cnt; |
| 552 | from = "RTEMS"; /* default: make "from" point to OS Name */ |
| 553 | if ((rqdata != NULL) && |
| 554 | (rqdata->OEMName != NULL)) { |
| 555 | from = rqdata->OEMName; |
| 556 | } |
| 557 | for (cnt = 0; |
| 558 | cnt < (sizeof(fmt_params->OEMName)-1); |
| 559 | cnt++) { |
| 560 | if (isprint(*from)) { |
| 561 | *to++ = *from++; |
| 562 | } |
| 563 | else { |
| 564 | /* |
| 565 | * non-printable character in given name, so keep stuck |
| 566 | * at that character and replace all following characters |
| 567 | * with a ' ' |
| 568 | */ |
| 569 | *to++=' '; |
| 570 | } |
| 571 | *to = '\0'; |
| 572 | } |
| 573 | } |
| 574 | |
| 575 | /* |
| 576 | * determine usable Volume Label |
| 577 | */ |
| 578 | if (ret_val == 0) { |
| 579 | const char *from; |
| 580 | char *to = fmt_params->VolLabel; |
| 581 | int cnt; |
| 582 | from = ""; /* default: make "from" point to empty string */ |
| 583 | if ((rqdata != NULL) && |
| 584 | (rqdata->VolLabel != NULL)) { |
| 585 | from = rqdata->VolLabel; |
| 586 | fmt_params->VolLabel_present = TRUE; |
| 587 | } |
| 588 | for (cnt = 0; |
| 589 | cnt < (sizeof(fmt_params->VolLabel)-1); |
| 590 | cnt++) { |
| 591 | if (isprint(*from)) { |
| 592 | *to++ = *from++; |
| 593 | } |
| 594 | else { |
| 595 | /* |
| 596 | * non-printable character in given name, so keep stuck |
| 597 | * at that character and replace all following characters |
| 598 | * with a ' ' |
| 599 | */ |
| 600 | *to++=' '; |
| 601 | } |
| 602 | *to = '\0'; |
| 603 | } |
| 604 | } |
| 605 | |
| 606 | /* |
| 607 | * determine usable Volume ID |
| 608 | */ |
| 609 | if (ret_val == 0) { |
| 610 | msdos_format_gen_volid(&(fmt_params->vol_id)); |
| 611 | } |
| 612 | /* |
| 613 | * Phuuu.... That's it. |
| 614 | */ |
| 615 | if (ret_val != 0) { |
| 616 | set_errno_and_return_minus_one(ret_val); |
| 617 | } |
| 618 | else { |
| 619 | return 0; |
| 620 | } |
| 621 | } |
| 622 | /*=========================================================================*\ |
| 623 | | Function: | |
| 624 | \*-------------------------------------------------------------------------*/ |
| 625 | static int msdos_format_gen_mbr |
| 626 | ( |
| 627 | /*-------------------------------------------------------------------------*\ |
| 628 | | Purpose: | |
| 629 | | create master boot record content from parameter set | |
| 630 | +---------------------------------------------------------------------------+ |
| 631 | | Input Parameters: | |
| 632 | \*-------------------------------------------------------------------------*/ |
| 633 | char mbr[], /* sector buffer */ |
| 634 | const msdos_format_param_t *fmt_params/* computed fmt parameters */ |
| 635 | ) |
| 636 | /*-------------------------------------------------------------------------*\ |
| 637 | | Return Value: | |
| 638 | | 0, if success, -1 and errno if failed | |
| 639 | \*=========================================================================*/ |
| 640 | { |
| 641 | unsigned32 total_sectors_num16 = 0; |
| 642 | unsigned32 total_sectors_num32 = 0; |
| 643 | |
| 644 | /* store total sector count in either 16 or 32 bit field in mbr */ |
| 645 | if (fmt_params->totl_sector_cnt < 0x10000) { |
| 646 | total_sectors_num16 = fmt_params->totl_sector_cnt; |
| 647 | } |
| 648 | else { |
| 649 | total_sectors_num32 = fmt_params->totl_sector_cnt; |
| 650 | } |
| 651 | /* |
| 652 | * finally we are there: let's fill in the values into the MBR |
| 653 | */ |
| 654 | memset(mbr,0,FAT_TOTAL_MBR_SIZE); |
| 655 | /* |
| 656 | * FIXME: fill jmpBoot and Boot code... |
| 657 | * with 0xEB,.... |
| 658 | */ |
| 659 | /* |
| 660 | * fill OEMName |
| 661 | */ |
| 662 | memcpy(FAT_GET_ADDR_BR_OEMNAME(mbr), |
| 663 | fmt_params->OEMName, |
| 664 | FAT_BR_OEMNAME_SIZE); |
| 665 | FAT_SET_BR_BYTES_PER_SECTOR(mbr , fmt_params->bytes_per_sector); |
| 666 | FAT_SET_BR_SECTORS_PER_CLUSTER(mbr , fmt_params->sectors_per_cluster); |
| 667 | FAT_SET_BR_RESERVED_SECTORS_NUM(mbr, fmt_params->rsvd_sector_cnt); |
| 668 | |
| 669 | /* number of FATs on medium */ |
| 670 | FAT_SET_BR_FAT_NUM(mbr , 2); /* standard/recommended value */ |
| 671 | FAT_SET_BR_FILES_PER_ROOT_DIR(mbr , fmt_params->files_per_root_dir); |
| 672 | FAT_SET_BR_TOTAL_SECTORS_NUM16(mbr , total_sectors_num16); |
| 673 | FAT_SET_BR_MEDIA(mbr , fmt_params->media_code); |
| 674 | |
| 675 | FAT_SET_BR_SECTORS_PER_TRACK(mbr , 0); /* only needed for INT13... */ |
| 676 | FAT_SET_BR_NUMBER_OF_HEADS(mbr , 0); /* only needed for INT13... */ |
| 677 | FAT_SET_BR_HIDDEN_SECTORS(mbr , 0); /* only needed for INT13... */ |
| 678 | |
| 679 | FAT_SET_BR_TOTAL_SECTORS_NUM32(mbr , total_sectors_num32); |
| 680 | if (fmt_params->fattype != FAT_FAT32) { |
| 681 | FAT_SET_BR_SECTORS_PER_FAT(mbr ,fmt_params->sectors_per_fat); |
| 682 | FAT_SET_BR_DRVNUM(mbr , 0); /* only needed for INT13... */ |
| 683 | FAT_SET_BR_RSVD1(mbr , 0); /* fill with zero */ |
| 684 | FAT_SET_BR_BOOTSIG(mbr , FAT_BR_BOOTSIG_VAL); |
| 685 | FAT_SET_BR_VOLID(mbr , fmt_params->vol_id); /* volume id */ |
| 686 | memcpy(FAT_GET_ADDR_BR_VOLLAB(mbr), |
| 687 | fmt_params->VolLabel, |
| 688 | FAT_BR_VOLLAB_SIZE); |
| 689 | memcpy(FAT_GET_ADDR_BR_FILSYSTYPE(mbr), |
| 690 | (fmt_params->fattype == FAT_FAT12) |
| 691 | ? "FAT12 " |
| 692 | : "FAT16 ", |
| 693 | FAT_BR_FILSYSTYPE_SIZE); |
| 694 | } |
| 695 | else { |
| 696 | FAT_SET_BR_SECTORS_PER_FAT32(mbr ,fmt_params->sectors_per_fat); |
| 697 | FAT_SET_BR_EXT_FLAGS(mbr , 0); |
| 698 | FAT_SET_BR_FSVER(mbr , 0); /* FAT32 Version:0.0 */ |
| 699 | FAT_SET_BR_FAT32_ROOT_CLUSTER(mbr , 2); /* put root dir to cluster 2 */ |
| 700 | FAT_SET_BR_FAT32_FS_INFO_SECTOR(mbr, 1); /* Put fsinfo to rsrvd sec 1*/ |
| 701 | FAT_SET_BR_FAT32_BK_BOOT_SECTOR(mbr, fmt_params->mbr_copy_sec ); /* Put MBR copy to rsrvd sec */ |
| 702 | memset(FAT_GET_ADDR_BR_FAT32_RESERVED(mbr),0,FAT_BR_FAT32_RESERVED_SIZE); |
| 703 | |
| 704 | FAT_SET_BR_FAT32_DRVNUM(mbr , 0); /* only needed for INT13... */ |
| 705 | FAT_SET_BR_FAT32_RSVD1(mbr , 0); /* fill with zero */ |
| 706 | FAT_SET_BR_FAT32_BOOTSIG(mbr ,FAT_BR_FAT32_BOOTSIG_VAL); |
| 707 | FAT_SET_BR_FAT32_VOLID(mbr , 0); /* not set */ |
| 708 | memset(FAT_GET_ADDR_BR_FAT32_VOLLAB(mbr) ,0,FAT_BR_VOLLAB_SIZE); |
| 709 | memcpy(FAT_GET_ADDR_BR_FAT32_FILSYSTYPE(mbr), |
| 710 | "FAT32 ", |
| 711 | FAT_BR_FILSYSTYPE_SIZE); |
| 712 | } |
| 713 | /* |
| 714 | * add boot record signature |
| 715 | */ |
| 716 | FAT_SET_BR_SIGNATURE(mbr, FAT_BR_SIGNATURE_VAL); |
| 717 | |
| 718 | /* |
| 719 | * add jump to boot loader at start of sector |
| 720 | */ |
| 721 | FAT_SET_VAL8(mbr,0,0xeb); |
| 722 | FAT_SET_VAL8(mbr,1,0x3c); |
| 723 | FAT_SET_VAL8(mbr,2,0x90); |
| 724 | /* |
| 725 | * FIXME: a nice little PC boot loader would be nice here. |
| 726 | * but where can I get one for free? |
| 727 | */ |
| 728 | /* |
| 729 | * Phuuu.... That's it. |
| 730 | */ |
| 731 | return 0; |
| 732 | } |
| 733 | |
| 734 | /*=========================================================================*\ |
| 735 | | Function: | |
| 736 | \*-------------------------------------------------------------------------*/ |
| 737 | static int msdos_format_gen_fsinfo |
| 738 | ( |
| 739 | /*-------------------------------------------------------------------------*\ |
| 740 | | Purpose: | |
| 741 | | create FAT32 fsinfo sector | |
| 742 | +---------------------------------------------------------------------------+ |
| 743 | | Input Parameters: | |
| 744 | \*-------------------------------------------------------------------------*/ |
| 745 | char fsinfo[] /* sector buffer */ |
| 746 | ) |
| 747 | /*-------------------------------------------------------------------------*\ |
| 748 | | Return Value: | |
| 749 | | 0, if success, -1 and errno if failed | |
| 750 | \*=========================================================================*/ |
| 751 | { |
| 752 | |
| 753 | /* |
| 754 | * clear fsinfo sector data |
| 755 | */ |
| 756 | memset(fsinfo,0,FAT_TOTAL_FSINFO_SIZE); |
| 757 | /* |
| 758 | * write LEADSIG, STRUCTSIG, TRAILSIG |
| 759 | */ |
| 760 | FAT_SET_FSINFO_LEAD_SIGNATURE (fsinfo,FAT_FSINFO_LEAD_SIGNATURE_VALUE ); |
| 761 | FAT_SET_FSINFO_STRUC_SIGNATURE(fsinfo,FAT_FSINFO_STRUC_SIGNATURE_VALUE); |
| 762 | FAT_SET_FSINFO_TRAIL_SIGNATURE(fsinfo,FAT_FSINFO_TRAIL_SIGNATURE_VALUE); |
| 763 | /* |
| 764 | * write "empty" values for free cluster count and next cluster number |
| 765 | */ |
| 766 | FAT_SET_FSINFO_FREE_CLUSTER_COUNT(fsinfo+FAT_FSI_INFO, |
| 767 | 0xffffffff); |
| 768 | FAT_SET_FSINFO_NEXT_FREE_CLUSTER (fsinfo+FAT_FSI_INFO, |
| 769 | 0xffffffff); |
| 770 | return 0; |
| 771 | } |
| 772 | |
| 773 | /*=========================================================================*\ |
| 774 | | Function: | |
| 775 | \*-------------------------------------------------------------------------*/ |
| 776 | int msdos_format |
| 777 | ( |
| 778 | /*-------------------------------------------------------------------------*\ |
| 779 | | Purpose: | |
| 780 | | format device with msdos filesystem | |
| 781 | +---------------------------------------------------------------------------+ |
| 782 | | Input Parameters: | |
| 783 | \*-------------------------------------------------------------------------*/ |
| 784 | const char *devname, /* device name */ |
| 785 | const msdos_format_request_param_t *rqdata /* requested fmt parameters */ |
| 786 | /* set to NULL for automatic */ |
| 787 | /* determination */ |
| 788 | ) |
| 789 | /*-------------------------------------------------------------------------*\ |
| 790 | | Return Value: | |
| 791 | | 0, if success, -1 and errno if failed | |
| 792 | \*=========================================================================*/ |
| 793 | { |
| 794 | char tmp_sec[FAT_TOTAL_MBR_SIZE]; |
| 795 | int rc; |
| 796 | disk_device *dd = NULL; |
| 797 | struct stat stat_buf; |
| 798 | int ret_val = 0; |
| 799 | int fd = -1; |
| 800 | int i; |
| 801 | msdos_format_param_t fmt_params; |
| 802 | |
| 803 | /* |
| 804 | * sanity check on device |
| 805 | */ |
| 806 | if (ret_val == 0) { |
| 807 | rc = stat(devname, &stat_buf); |
| 808 | ret_val = rc; |
| 809 | } |
| 810 | |
| 811 | /* rtems feature: no block devices, all are character devices */ |
| 812 | if ((ret_val == 0) && |
| 813 | (!S_ISCHR(stat_buf.st_mode))) { |
| 814 | errno = ENOTBLK; |
| 815 | ret_val = -1; |
| 816 | } |
| 817 | |
| 818 | /* check that device is registered as block device and lock it */ |
| 819 | if (ret_val == 0) { |
| 820 | dd = rtems_disk_lookup(stat_buf.st_dev); |
| 821 | if (dd == NULL) { |
| 822 | errno = ENOTBLK; |
| 823 | ret_val = -1; |
| 824 | } |
| 825 | } |
| 826 | |
| 827 | /* |
| 828 | * open device for writing |
| 829 | */ |
| 830 | if (ret_val == 0) { |
| 831 | fd = open(devname, O_WRONLY); |
| 832 | if (fd == -1) |
| 833 | { |
| 834 | ret_val= -1; |
| 835 | } |
| 836 | } |
| 837 | |
| 838 | /* |
| 839 | * compute formatting parameters |
| 840 | */ |
| 841 | if (ret_val == 0) { |
| 842 | ret_val = msdos_format_determine_fmt_params(dd,rqdata,&fmt_params); |
| 843 | } |
| 844 | /* |
| 845 | * if requested, write whole disk/partition with 0xe5 |
| 846 | */ |
| 847 | if ((ret_val == 0) && |
| 848 | (rqdata != NULL) && |
| 849 | !(rqdata->quick_format)) { |
| 850 | ret_val = msdos_format_fill_sectors |
| 851 | (fd, |
| 852 | 0, /* start sector */ |
| 853 | fmt_params.totl_sector_cnt, /* sector count */ |
| 854 | fmt_params.bytes_per_sector, |
| 855 | 0xe5); |
| 856 | } |
| 857 | /* |
| 858 | * create master boot record |
| 859 | */ |
| 860 | if (ret_val == 0) { |
| 861 | ret_val = msdos_format_gen_mbr(tmp_sec,&fmt_params); |
| 862 | } |
| 863 | /* |
| 864 | * write master boot record to disk |
| 865 | * also write copy of MBR to disk |
| 866 | */ |
| 867 | if (ret_val == 0) { |
| 868 | ret_val = msdos_format_write_sec(fd, |
| 869 | 0, |
| 870 | fmt_params.bytes_per_sector, |
| 871 | (void *)tmp_sec); |
| 872 | } |
| 873 | if ((ret_val == 0) && |
| 874 | (fmt_params.mbr_copy_sec != 0)) { |
| 875 | /* |
| 876 | * write copy of MBR |
| 877 | */ |
| 878 | ret_val = msdos_format_write_sec(fd, |
| 879 | fmt_params.mbr_copy_sec , |
| 880 | fmt_params.bytes_per_sector, |
| 881 | (void *)tmp_sec); |
| 882 | } |
| 883 | /* |
| 884 | * for FAT32: initialize info sector on disk |
| 885 | */ |
| 886 | if ((ret_val == 0) && |
| 887 | (fmt_params.fsinfo_sec != 0)) { |
| 888 | ret_val = msdos_format_gen_fsinfo(tmp_sec); |
| 889 | } |
| 890 | /* |
| 891 | * write fsinfo sector |
| 892 | */ |
| 893 | if ((ret_val == 0) && |
| 894 | (fmt_params.fsinfo_sec != 0)) { |
| 895 | ret_val = msdos_format_write_sec(fd, |
| 896 | fmt_params.fsinfo_sec, |
| 897 | fmt_params.bytes_per_sector, |
| 898 | (void *)tmp_sec); |
| 899 | } |
| 900 | /* |
| 901 | * write FAT as all empty |
| 902 | * -> write all FAT sectors as zero |
| 903 | */ |
| 904 | if (ret_val == 0) { |
| 905 | ret_val = msdos_format_fill_sectors |
| 906 | (fd, |
| 907 | fmt_params.rsvd_sector_cnt, /* start sector */ |
| 908 | fmt_params.fat_num*fmt_params.sectors_per_fat,/* sector count */ |
| 909 | fmt_params.bytes_per_sector, |
| 910 | 0x00); |
| 911 | } |
| 912 | /* |
| 913 | * clear/init root directory |
| 914 | * -> write all directory sectors as 0x00 |
| 915 | */ |
| 916 | if (ret_val == 0) { |
| 917 | ret_val = msdos_format_fill_sectors |
| 918 | (fd, |
| 919 | fmt_params.root_dir_start_sec, /* start sector */ |
| 920 | fmt_params.root_dir_fmt_sec_cnt, /* sector count */ |
| 921 | fmt_params.bytes_per_sector, |
| 922 | 0x00); |
| 923 | } |
| 924 | /* |
| 925 | * write volume label to first entry of directory |
| 926 | */ |
| 927 | if ((ret_val == 0) && fmt_params.VolLabel_present) { |
| 928 | memset(tmp_sec,0,sizeof(tmp_sec)); |
| 929 | memcpy(MSDOS_DIR_NAME(tmp_sec),fmt_params.VolLabel,MSDOS_SHORT_NAME_LEN); |
| 930 | *MSDOS_DIR_ATTR(tmp_sec) = MSDOS_ATTR_VOLUME_ID; |
| 931 | ret_val = msdos_format_write_sec |
| 932 | (fd, |
| 933 | fmt_params.root_dir_start_sec, |
| 934 | fmt_params.bytes_per_sector, |
| 935 | tmp_sec); |
| 936 | } |
| 937 | /* |
| 938 | * write FAT entry 0 as (0xffffff00|Media_type)EOC, |
| 939 | * write FAT entry 1 as EOC |
| 940 | * allocate directory in a FAT32 FS |
| 941 | */ |
| 942 | if ((ret_val == 0) && fmt_params.VolLabel_present){ |
| 943 | /* |
| 944 | * empty sector: all clusters are free/do not link further on |
| 945 | */ |
| 946 | memset(tmp_sec,0,sizeof(tmp_sec)); |
| 947 | |
| 948 | switch(fmt_params.fattype) { |
| 949 | case FAT_FAT12: |
| 950 | /* LSBits of FAT entry 0: media_type */ |
| 951 | FAT_SET_VAL8(tmp_sec,0,(fmt_params.media_code)); |
| 952 | /* MSBits of FAT entry 0:0xf, LSBits of FAT entry 1: LSB of EOC */ |
| 953 | FAT_SET_VAL8(tmp_sec,1,(0x0f | (FAT_FAT12_EOC << 4))); |
| 954 | /* MSBits of FAT entry 1: MSBits of EOC */ |
| 955 | FAT_SET_VAL8(tmp_sec,2,(FAT_FAT12_EOC >> 4)); |
| 956 | break; |
| 957 | |
| 958 | case FAT_FAT16: |
| 959 | /* FAT entry 0: 0xff00|media_type */ |
| 960 | FAT_SET_VAL16(tmp_sec,0,0xff00|fmt_params.media_code); |
| 961 | /* FAT entry 1: EOC */ |
| 962 | FAT_SET_VAL16(tmp_sec,2,FAT_FAT16_EOC); |
| 963 | break; |
| 964 | |
| 965 | case FAT_FAT32: |
| 966 | /* FAT entry 0: 0xffffff00|media_type */ |
| 967 | FAT_SET_VAL32(tmp_sec,0,0xffffff00|fmt_params.media_code); |
| 968 | /* FAT entry 1: EOC */ |
| 969 | FAT_SET_VAL32(tmp_sec,4,FAT_FAT32_EOC); |
| 970 | break; |
| 971 | |
| 972 | default: |
| 973 | ret_val = -1; |
| 974 | errno = EINVAL; |
| 975 | } |
| 976 | if (fmt_params.fattype == FAT_FAT32) { |
| 977 | /* |
| 978 | * only first valid cluster (cluster number 2) belongs |
| 979 | * to root directory, and is end of chain |
| 980 | * mark this in every copy of the FAT |
| 981 | */ |
| 982 | FAT_SET_VAL32(tmp_sec,8,FAT_FAT32_EOC); |
| 983 | } |
| 984 | for (i = 0; |
| 985 | (i < fmt_params.fat_num) && (ret_val == 0); |
| 986 | i++) { |
| 987 | ret_val = msdos_format_write_sec |
| 988 | (fd, |
| 989 | fmt_params.rsvd_sector_cnt |
| 990 | + (i * fmt_params.sectors_per_fat), |
| 991 | fmt_params.bytes_per_sector, |
| 992 | tmp_sec); |
| 993 | } |
| 994 | } |
| 995 | /* |
| 996 | * cleanup: |
| 997 | * sync and unlock disk |
| 998 | * free any data structures (not needed now) |
| 999 | */ |
| 1000 | if (fd != -1) { |
| 1001 | close(fd); |
| 1002 | } |
| 1003 | if (dd != NULL) { |
| 1004 | rtems_disk_release(dd); |
| 1005 | } |
| 1006 | return ret_val; |
| 1007 | } |