mkfs/main.c

   1 /*
   2         main.c (15.08.10)
   3         Creates exFAT file system.
   4
   5         Copyright (C) 2009, 2010  Andrew Nayenko
   6
   7         This program is free software: you can redistribute it and/or modify
   8         it under the terms of the GNU General Public License as published by
   9         the Free Software Foundation, either version 3 of the License, or
  10         (at your option) any later version.
  11
  12         This program is distributed in the hope that it will be useful,
  13         but WITHOUT ANY WARRANTY; without even the implied warranty of
  14         MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15         GNU General Public License for more details.
  16
  17         You should have received a copy of the GNU General Public License
  18         along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20
  21 #include <sys/types.h>
  22 #include <sys/stat.h>
  23 #include <sys/time.h>
  24 #include <fcntl.h>
  25 #include <unistd.h>
  26 #include <inttypes.h>
  27 #include <stdio.h>
  28 #include <string.h>
  29 #include <limits.h>
  30 #include <errno.h>
  31 #include <exfat.h>
  32 #include "vbr.h"
  33 #include "fat.h"
  34 #include "cbm.h"
  35 #include "uct.h"
  36 #include "rootdir.h"
  37
  38 #define ROUND_UP(x, d) (DIV_ROUND_UP(x, d) * (d))
  39
  40 struct exfat_super_block sb;
  41 struct exfat_entry_label label_entry = {EXFAT_ENTRY_LABEL ^ EXFAT_ENTRY_VALID};
  42 struct exfat_entry_bitmap bitmap_entry = {EXFAT_ENTRY_BITMAP};
  43 struct exfat_entry_upcase upcase_entry = {EXFAT_ENTRY_UPCASE};
  44
  45 struct exfat_structure
  46 {
  47         const char* name;
  48         int order;
  49         off_t (*get_alignment)(void);
  50         off_t (*get_size)(void);
  51         int (*write_data)(off_t, int);
  52 };
  53
  54 static int init_sb(off_t volume_size, int block_bits, int bpc_bits,
  55                 uint32_t volume_serial)
  56 {
  57         uint32_t clusters_max = (volume_size >> block_bits >> bpc_bits);
  58         uint32_t fat_blocks = DIV_ROUND_UP(clusters_max * 4, 1 << block_bits);
  59         uint32_t allocated_clusters;
  60
  61         memset(&sb, 0, sizeof(struct exfat_super_block));
  62         sb.jump[0] = 0xeb;
  63         sb.jump[1] = 0x76;
  64         sb.jump[2] = 0x90;
  65         memcpy(sb.oem_name, "EXFAT   ", sizeof(sb.oem_name));
  66         sb.block_start = cpu_to_le64(0); /* FIXME */
  67         sb.block_count = cpu_to_le64(volume_size >> block_bits);
  68         sb.fat_block_start = cpu_to_le32(128); /* FIXME */
  69         sb.fat_block_count = cpu_to_le32(ROUND_UP(
  70                         le32_to_cpu(sb.fat_block_start) + fat_blocks, 1 << bpc_bits) -
  71                         le32_to_cpu(sb.fat_block_start));
  72         /* cluster_block_start will be set later */
  73         sb.cluster_count = cpu_to_le32(clusters_max -
  74                         ((le32_to_cpu(sb.fat_block_start) +
  75                           le32_to_cpu(sb.fat_block_count)) >> bpc_bits));
  76         /* rootdir_cluster will be set later */
  77         sb.volume_serial = cpu_to_le32(volume_serial);
  78         sb.version.major = 1;
  79         sb.version.minor = 0;
  80         sb.volume_state = cpu_to_le16(0);
  81         sb.block_bits = block_bits;
  82         sb.bpc_bits = bpc_bits;
  83         sb.fat_count = 1;
  84         sb.drive_no = 0x80;
  85         sb.allocated_percent = 0;
  86         sb.boot_signature = cpu_to_le16(0xaa55);
  87
  88         allocated_clusters =
  89                         DIV_ROUND_UP(cbm_size(), CLUSTER_SIZE(sb)) +
  90                         DIV_ROUND_UP(uct_size(), CLUSTER_SIZE(sb)) +
  91                         DIV_ROUND_UP(rootdir_size(), CLUSTER_SIZE(sb));
  92         exfat_print_info(&sb, le32_to_cpu(sb.cluster_count) -
  93                         allocated_clusters);
  94         return 0;
  95 }
  96
  97 static int erase_device(int fd)
  98 {
  99         uint64_t erase_blocks = (uint64_t)
 100                         le32_to_cpu(sb.fat_block_start) +
 101                         le32_to_cpu(sb.fat_block_count) +
 102                         DIV_ROUND_UP(cbm_size(), 1 << sb.block_bits) +
 103                         DIV_ROUND_UP(uct_size(), 1 << sb.block_bits) +
 104                         DIV_ROUND_UP(rootdir_size(), 1 << sb.block_bits);
 105         uint64_t i;
 106         void* block;
 107
 108         if (lseek(fd, 0, SEEK_SET) == (off_t) -1)
 109         {
 110                 exfat_error("seek failed");
 111                 return 1;
 112         }
 113
 114         block = malloc(BLOCK_SIZE(sb));
 115         if (block == NULL)
 116         {
 117                 exfat_error("failed to allocate erase block");
 118                 return 1;
 119         }
 120         memset(block, 0, BLOCK_SIZE(sb));
 121
 122         for (i = 0; i < erase_blocks; i++)
 123         {
 124                 if (write(fd, block, BLOCK_SIZE(sb)) == -1)
 125                 {
 126                         free(block);
 127                         exfat_error("failed to erase block %"PRIu64, i);
 128                         return 1;
 129                 }
 130                 if (i * 100 / erase_blocks != (i + 1) * 100 / erase_blocks)
 131                 {
 132                         printf("\b\b\b%2"PRIu64"%%", (i + 1) * 100 / erase_blocks);
 133                         fflush(stdout);
 134                 }
 135         }
 136         free(block);
 137         return 0;
 138 }
 139
 140 /*
 141  * exFAT layout:
 142  * - Volume Boot Record (VBR)
 143  *   - Main Boot Sector (MBR)
 144  *   - Main Extended Boot Sectors (MEBS)
 145  *   - OEM Parameters
 146  *   - Reserved sector
 147  *   - Checksum sector
 148  * - Volume Boot Record copy
 149  * - File Allocation Table (FAT)
 150  * - Clusters heap
 151  *   - Clusters bitmap
 152  *   - Upper case table
 153  *   - Root directory
 154  */
 155 #define FS_OBJECT(order, name) \
 156         {#name, order, name##_alignment, name##_size, name##_write}
 157 static struct exfat_structure structures[] =
 158 {
 159         FS_OBJECT(3, vbr),
 160         FS_OBJECT(3, vbr),
 161         FS_OBJECT(2, fat),
 162         FS_OBJECT(1, cbm),
 163         FS_OBJECT(1, uct),
 164         FS_OBJECT(1, rootdir)
 165 };
 166 #undef FS_OBJECT
 167
 168 static off_t write_structure(int fd, struct exfat_structure* structure,
 169                 off_t current)
 170 {
 171         off_t alignment = structure->get_alignment();
 172         off_t base = ROUND_UP(current, alignment);
 173
 174         if (lseek(fd, base, SEEK_SET) == (off_t) -1)
 175         {
 176                 exfat_error("seek to %"PRIu64" failed", base);
 177                 return -1;
 178         }
 179         if (structure->order > 0)
 180         {
 181                 int rc = structure->write_data(base, fd);
 182                 if (rc != 0)
 183                 {
 184                         exfat_error("%s creation failed: %s", structure->name,
 185                                         strerror(rc));
 186                         return -1;
 187                 }
 188                 structure->order--;
 189         }
 190         return base + structure->get_size();
 191 }
 192
 193 static int write_structures(int fd)
 194 {
 195         off_t current;
 196         size_t i;
 197         int remainder;
 198
 199         do
 200         {
 201                 current = 0;
 202                 remainder = 0;
 203                 for (i = 0; i < sizeof(structures) / sizeof(structures[0]); i++)
 204                 {
 205                         current = write_structure(fd, &structures[i], current);
 206                         if (current == (off_t) -1)
 207                                 return 1;
 208                         remainder += structures[i].order;
 209                 }
 210         }
 211         while (remainder > 0);
 212         return 0;
 213 }
 214
 215 static int get_bpc_bits(int user_defined, off_t volume_size)
 216 {
 217         if (user_defined != -1)
 218                 return user_defined;
 219
 220         if (volume_size < 256ull * 1024 * 1024)
 221                 return 3;       /* 4 KB */
 222         else if (volume_size < 32ull * 1024 * 1024 * 1024)
 223                 return 6;       /* 32 KB */
 224         else
 225                 return 8;       /* 128 KB */
 226 }
 227
 228 static int set_volume_label(int fd, const char* volume_label)
 229 {
 230         le16_t tmp[EXFAT_ENAME_MAX + 1];
 231
 232         if (volume_label == NULL)
 233                 return 0;
 234
 235         memset(tmp, 0, sizeof(tmp));
 236         if (utf8_to_utf16(tmp, volume_label, EXFAT_ENAME_MAX,
 237                                 strlen(volume_label)) != 0)
 238         {
 239                 close(fd);
 240                 return 1;
 241         }
 242         memcpy(label_entry.name, tmp, EXFAT_ENAME_MAX * sizeof(le16_t));
 243         label_entry.length = utf16_length(tmp);
 244         label_entry.type |= EXFAT_ENTRY_VALID;
 245         return 0;
 246 }
 247
 248 static uint32_t get_volume_serial(uint32_t user_defined)
 249 {
 250         struct timeval now;
 251
 252         if (user_defined != 0)
 253                 return user_defined;
 254
 255         if (gettimeofday(&now, NULL) != 0)
 256                 return 0;
 257         return (now.tv_sec << 20) | now.tv_usec;
 258 }
 259
 260 static int mkfs(const char* spec, int block_bits, int bpc_bits,
 261                 const char* volume_label, uint32_t volume_serial)
 262 {
 263         int fd;
 264         off_t volume_size;
 265         char spec_abs[PATH_MAX];
 266
 267         if (realpath(spec, spec_abs) == NULL)
 268         {
 269                 exfat_error("failed to get absolute path for `%s'", spec);
 270                 return 1;
 271         }
 272
 273         fd = open(spec_abs, O_RDWR);
 274         if (fd < 0)
 275         {
 276                 exfat_error("failed to open special file `%s'", spec_abs);
 277                 return 1;
 278         }
 279
 280         volume_size = lseek(fd, 0, SEEK_END);
 281         if (volume_size == (off_t) -1)
 282         {
 283                 close(fd);
 284                 exfat_error("seek failed");
 285                 return 1;
 286         }
 287         bpc_bits = get_bpc_bits(bpc_bits, volume_size);
 288
 289         if (set_volume_label(fd, volume_label) != 0)
 290         {
 291                 close(fd);
 292                 return 1;
 293         }
 294
 295         volume_serial = get_volume_serial(volume_serial);
 296         if (volume_serial == 0)
 297         {
 298                 close(fd);
 299                 exfat_error("failed to get current time to form volume id");
 300                 return 1;
 301         }
 302
 303         init_sb(volume_size, block_bits, bpc_bits, volume_serial);
 304
 305         printf("Creating... %2u%%", 0);
 306         fflush(stdout);
 307         if (erase_device(fd) != 0)
 308         {
 309                 close(fd);
 310                 return 1;
 311         }
 312         if (write_structures(fd) != 0)
 313         {
 314                 close(fd);
 315                 return 1;
 316         }
 317         puts("\b\b\b\bdone.");
 318
 319         printf("Flushing... ");
 320         fflush(stdout);
 321         if (fsync(fd) < 0)
 322         {
 323                 close(fd);
 324                 exfat_error("fsync failed for `%s'", spec_abs);
 325                 return 1;
 326         }
 327         puts("done.");
 328         if (close(fd) < 0)
 329         {
 330                 exfat_error("close failed for `%s'", spec_abs);
 331                 return 1;
 332         }
 333         printf("File system created successfully.\n");
 334         return 0;
 335 }
 336
 337 static int logarithm2(int n)
 338 {
 339         int i;
 340
 341         for (i = 0; i < sizeof(int) * CHAR_BIT - 1; i++)
 342                 if ((1 << i) == n)
 343                         return i;
 344         return -1;
 345 }
 346
 347 static void usage(const char* prog)
 348 {
 349         fprintf(stderr, "Usage: %s [-i volume-id] [-n label] "
 350                         "[-s sectors-per-cluster] <device>\n", prog);
 351         exit(1);
 352 }
 353
 354 int main(int argc, char* argv[])
 355 {
 356         const char* spec = NULL;
 357         char** pp;
 358         int bpc_bits = -1;
 359         const char* volume_label = NULL;
 360         uint32_t volume_serial = 0;
 361
 362         for (pp = argv + 1; *pp; pp++)
 363         {
 364                 if (strcmp(*pp, "-s") == 0)
 365                 {
 366                         pp++;
 367                         if (*pp == NULL)
 368                                 usage(argv[0]);
 369                         bpc_bits = logarithm2(atoi(*pp));
 370                         if (bpc_bits < 0)
 371                         {
 372                                 exfat_error("invalid option value: `%s'", *pp);
 373                                 return 1;
 374                         }
 375                 }
 376                 else if (strcmp(*pp, "-n") == 0)
 377                 {
 378                         pp++;
 379                         if (*pp == NULL)
 380                                 usage(argv[0]);
 381                         volume_label = *pp;
 382                         /* TODO check length */
 383                 }
 384                 else if (strcmp(*pp, "-i") == 0)
 385                 {
 386                         pp++;
 387                         if (*pp == NULL)
 388                                 usage(argv[0]);
 389                         volume_serial = strtol(*pp, NULL, 16);
 390                 }
 391                 else if (**pp == '-')
 392                 {
 393                         exfat_error("unrecognized option `%s'", *pp);
 394                         return 1;
 395                 }
 396                 else
 397                         spec = *pp;
 398         }
 399         if (spec == NULL)
 400                 usage(argv[0]);
 401
 402         printf("mkexfatfs %u.%u.%u\n",
 403                         EXFAT_VERSION_MAJOR, EXFAT_VERSION_MINOR, EXFAT_VERSION_PATCH);
 404
 405         return mkfs(spec, 9, bpc_bits, volume_label, volume_serial);
 406 }