1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Copyright (C) 2019 Namjae Jeon <linkinjeon@kernel.org>
11 #include <sys/types.h>
13 #include <sys/ioctl.h>
22 #include "exfat_ondisk.h"
26 struct exfat_mkfs_info finfo;
28 /* random serial generator based on current time */
29 static unsigned int get_new_serial(void)
33 if (clock_gettime(CLOCK_REALTIME, &ts)) {
34 /* set 0000-0000 on error */
39 return (unsigned int)(ts.tv_nsec << 12 | ts.tv_sec);
42 static void exfat_setup_boot_sector(struct pbr *ppbr,
43 struct exfat_blk_dev *bd, struct exfat_user_input *ui)
45 struct bpb64 *pbpb = &ppbr->bpb;
46 struct bsx64 *pbsx = &ppbr->bsx;
49 /* Fill exfat BIOS paramemter block */
50 pbpb->jmp_boot[0] = 0xeb;
51 pbpb->jmp_boot[1] = 0x76;
52 pbpb->jmp_boot[2] = 0x90;
53 memcpy(pbpb->oem_name, "EXFAT ", 8);
54 memset(pbpb->res_zero, 0, 53);
56 /* Fill exfat extend BIOS paramemter block */
57 pbsx->vol_offset = cpu_to_le64(bd->offset / bd->sector_size);
58 pbsx->vol_length = cpu_to_le64(bd->size / bd->sector_size);
59 pbsx->fat_offset = cpu_to_le32(finfo.fat_byte_off / bd->sector_size);
60 pbsx->fat_length = cpu_to_le32(finfo.fat_byte_len / bd->sector_size);
61 pbsx->clu_offset = cpu_to_le32(finfo.clu_byte_off / bd->sector_size);
62 pbsx->clu_count = cpu_to_le32(finfo.total_clu_cnt);
63 pbsx->root_cluster = cpu_to_le32(finfo.root_start_clu);
64 pbsx->vol_serial = cpu_to_le32(finfo.volume_serial);
66 pbsx->sect_size_bits = bd->sector_size_bits;
67 pbsx->sect_per_clus_bits = 0;
68 /* Compute base 2 logarithm of ui->cluster_size / bd->sector_size */
69 for (i = ui->cluster_size / bd->sector_size; i > 1; i /= 2)
70 pbsx->sect_per_clus_bits++;
72 /* fs_version[0] : minor and fs_version[1] : major */
73 pbsx->fs_version[0] = 0;
74 pbsx->fs_version[1] = 1;
75 memset(pbsx->reserved2, 0, 7);
77 memset(ppbr->boot_code, 0, 390);
78 ppbr->signature = cpu_to_le16(PBR_SIGNATURE);
80 exfat_debug("Volume Offset(sectors) : %" PRIu64 "\n",
81 le64_to_cpu(pbsx->vol_offset));
82 exfat_debug("Volume Length(sectors) : %" PRIu64 "\n",
83 le64_to_cpu(pbsx->vol_length));
84 exfat_debug("FAT Offset(sector offset) : %u\n",
85 le32_to_cpu(pbsx->fat_offset));
86 exfat_debug("FAT Length(sectors) : %u\n",
87 le32_to_cpu(pbsx->fat_length));
88 exfat_debug("Cluster Heap Offset (sector offset) : %u\n",
89 le32_to_cpu(pbsx->clu_offset));
90 exfat_debug("Cluster Count : %u\n",
91 le32_to_cpu(pbsx->clu_count));
92 exfat_debug("Root Cluster (cluster offset) : %u\n",
93 le32_to_cpu(pbsx->root_cluster));
94 exfat_debug("Volume Serial : 0x%x\n", le32_to_cpu(pbsx->vol_serial));
95 exfat_debug("Sector Size Bits : %u\n",
96 pbsx->sect_size_bits);
97 exfat_debug("Sector per Cluster bits : %u\n",
98 pbsx->sect_per_clus_bits);
101 static int exfat_write_boot_sector(struct exfat_blk_dev *bd,
102 struct exfat_user_input *ui, unsigned int *checksum,
106 unsigned int sec_idx = BOOT_SEC_IDX;
110 sec_idx += BACKUP_BOOT_SEC_IDX;
112 ppbr = malloc(sizeof(struct pbr));
114 exfat_err("Cannot allocate pbr: out of memory\n");
117 memset(ppbr, 0, sizeof(struct pbr));
119 exfat_setup_boot_sector(ppbr, bd, ui);
121 /* write main boot sector */
122 ret = exfat_write_sector(bd, ppbr, sec_idx);
124 exfat_err("main boot sector write failed\n");
129 boot_calc_checksum((unsigned char *)ppbr, sizeof(struct pbr),
137 static int exfat_write_extended_boot_sectors(struct exfat_blk_dev *bd,
138 unsigned int *checksum, bool is_backup)
142 unsigned int sec_idx = EXBOOT_SEC_IDX;
145 sec_idx += BACKUP_BOOT_SEC_IDX;
147 memset(&eb, 0, sizeof(struct exbs));
148 eb.signature = cpu_to_le16(PBR_SIGNATURE);
149 for (i = 0; i < EXBOOT_SEC_NUM; i++) {
150 if (exfat_write_sector(bd, &eb, sec_idx++)) {
151 exfat_err("extended boot sector write failed\n");
155 boot_calc_checksum((unsigned char *) &eb, sizeof(struct exbs),
162 static int exfat_write_oem_sector(struct exfat_blk_dev *bd,
163 unsigned int *checksum, bool is_backup)
167 unsigned int sec_idx = OEM_SEC_IDX;
169 oem = malloc(bd->sector_size);
174 sec_idx += BACKUP_BOOT_SEC_IDX;
176 memset(oem, 0xFF, bd->sector_size);
177 ret = exfat_write_sector(bd, oem, sec_idx);
179 exfat_err("oem sector write failed\n");
184 boot_calc_checksum((unsigned char *)oem, bd->sector_size, false,
187 /* Zero out reserved sector */
188 memset(oem, 0, bd->sector_size);
189 ret = exfat_write_sector(bd, oem, sec_idx + 1);
191 exfat_err("reserved sector write failed\n");
196 boot_calc_checksum((unsigned char *)oem, bd->sector_size, false,
204 static int exfat_create_volume_boot_record(struct exfat_blk_dev *bd,
205 struct exfat_user_input *ui, bool is_backup)
207 unsigned int checksum = 0;
210 ret = exfat_write_boot_sector(bd, ui, &checksum, is_backup);
213 ret = exfat_write_extended_boot_sectors(bd, &checksum, is_backup);
216 ret = exfat_write_oem_sector(bd, &checksum, is_backup);
220 return exfat_write_checksum_sector(bd, checksum, is_backup);
223 static int write_fat_entry(int fd, __le32 clu,
224 unsigned long long offset)
228 lseek(fd, finfo.fat_byte_off + (offset * sizeof(__le32)), SEEK_SET);
229 nbyte = write(fd, (__u8 *) &clu, sizeof(__le32));
230 if (nbyte != sizeof(int)) {
231 exfat_err("write failed, offset : %llu, clu : %x\n",
239 static int write_fat_entries(struct exfat_user_input *ui, int fd,
240 unsigned int clu, unsigned int length)
245 count = clu + round_up(length, ui->cluster_size) / ui->cluster_size;
247 for (; clu < count - 1; clu++) {
248 ret = write_fat_entry(fd, cpu_to_le32(clu + 1), clu);
253 ret = write_fat_entry(fd, cpu_to_le32(EXFAT_EOF_CLUSTER), clu);
260 static int exfat_create_fat_table(struct exfat_blk_dev *bd,
261 struct exfat_user_input *ui)
265 /* fat entry 0 should be media type field(0xF8) */
266 ret = write_fat_entry(bd->dev_fd, cpu_to_le32(0xfffffff8), 0);
268 exfat_err("fat 0 entry write failed\n");
272 /* fat entry 1 is historical precedence(0xFFFFFFFF) */
273 ret = write_fat_entry(bd->dev_fd, cpu_to_le32(0xffffffff), 1);
275 exfat_err("fat 1 entry write failed\n");
279 /* write bitmap entries */
280 clu = write_fat_entries(ui, bd->dev_fd, EXFAT_FIRST_CLUSTER,
281 finfo.bitmap_byte_len);
285 /* write upcase table entries */
286 clu = write_fat_entries(ui, bd->dev_fd, clu + 1, finfo.ut_byte_len);
290 /* write root directory entries */
291 clu = write_fat_entries(ui, bd->dev_fd, clu + 1, finfo.root_byte_len);
295 finfo.used_clu_cnt = clu + 1;
296 exfat_debug("Total used cluster count : %d\n", finfo.used_clu_cnt);
301 static int exfat_create_bitmap(struct exfat_blk_dev *bd)
304 unsigned int i, nbytes;
306 bitmap = calloc(finfo.bitmap_byte_len, sizeof(*bitmap));
310 for (i = 0; i < finfo.used_clu_cnt - EXFAT_FIRST_CLUSTER; i++)
311 exfat_set_bit(bd, bitmap, i);
313 lseek(bd->dev_fd, finfo.bitmap_byte_off, SEEK_SET);
314 nbytes = write(bd->dev_fd, bitmap, finfo.bitmap_byte_len);
315 if (nbytes != finfo.bitmap_byte_len) {
316 exfat_err("write failed, nbytes : %d, bitmap_len : %d\n",
317 nbytes, finfo.bitmap_byte_len);
326 static int exfat_create_root_dir(struct exfat_blk_dev *bd,
327 struct exfat_user_input *ui)
329 struct exfat_dentry ed[3];
330 int dentries_len = sizeof(struct exfat_dentry) * 3;
333 /* Set volume label entry */
334 ed[0].type = EXFAT_VOLUME;
335 memset(ed[0].vol_label, 0, 22);
336 memcpy(ed[0].vol_label, ui->volume_label, ui->volume_label_len);
337 ed[0].vol_char_cnt = ui->volume_label_len/2;
339 /* Set bitmap entry */
340 ed[1].type = EXFAT_BITMAP;
341 ed[1].bitmap_flags = 0;
342 ed[1].bitmap_start_clu = cpu_to_le32(EXFAT_FIRST_CLUSTER);
343 ed[1].bitmap_size = cpu_to_le64(finfo.bitmap_byte_len);
345 /* Set upcase table entry */
346 ed[2].type = EXFAT_UPCASE;
347 ed[2].upcase_checksum = cpu_to_le32(0xe619d30d);
348 ed[2].upcase_start_clu = cpu_to_le32(finfo.ut_start_clu);
349 ed[2].upcase_size = cpu_to_le64(EXFAT_UPCASE_TABLE_SIZE);
351 lseek(bd->dev_fd, finfo.root_byte_off, SEEK_SET);
352 nbytes = write(bd->dev_fd, ed, dentries_len);
353 if (nbytes != dentries_len) {
354 exfat_err("write failed, nbytes : %d, dentries_len : %d\n",
355 nbytes, dentries_len);
362 static void usage(void)
364 fputs("Usage: mkfs.exfat\n"
365 "\t-L | --volume-label=label Set volume label\n"
366 "\t-c | --cluster-size=size(or suffixed by 'K' or 'M') Specify cluster size\n"
367 "\t-b | --boundary-align=size(or suffixed by 'K' or 'M') Specify boundary alignment\n"
368 "\t --pack-bitmap Move bitmap into FAT segment\n"
369 "\t-f | --full-format Full format\n"
370 "\t-V | --version Show version\n"
371 "\t-v | --verbose Print debug\n"
372 "\t-h | --help Show help\n",
378 #define PACK_BITMAP (CHAR_MAX + 1)
380 static const struct option opts[] = {
381 {"volume-label", required_argument, NULL, 'L' },
382 {"cluster-size", required_argument, NULL, 'c' },
383 {"boundary-align", required_argument, NULL, 'b' },
384 {"pack-bitmap", no_argument, NULL, PACK_BITMAP },
385 {"full-format", no_argument, NULL, 'f' },
386 {"version", no_argument, NULL, 'V' },
387 {"verbose", no_argument, NULL, 'v' },
388 {"help", no_argument, NULL, 'h' },
389 {"?", no_argument, NULL, '?' },
394 * Moves the bitmap to just before the alignment boundary if there is space
395 * between the boundary and the end of the FAT. This may allow the FAT and the
396 * bitmap to share the same allocation unit on flash media, thereby improving
397 * performance and endurance.
399 static int exfat_pack_bitmap(const struct exfat_user_input *ui)
401 unsigned int fat_byte_end = finfo.fat_byte_off + finfo.fat_byte_len,
402 bitmap_byte_len = finfo.bitmap_byte_len,
403 bitmap_clu_len = round_up(bitmap_byte_len, ui->cluster_size),
404 bitmap_clu_cnt, total_clu_cnt, new_bitmap_clu_len;
407 bitmap_clu_cnt = bitmap_clu_len / ui->cluster_size;
408 if (finfo.clu_byte_off - bitmap_clu_len < fat_byte_end ||
409 finfo.total_clu_cnt > EXFAT_MAX_NUM_CLUSTER -
412 total_clu_cnt = finfo.total_clu_cnt + bitmap_clu_cnt;
413 bitmap_byte_len = round_up(total_clu_cnt, 8) / 8;
414 new_bitmap_clu_len = round_up(bitmap_byte_len, ui->cluster_size);
415 if (new_bitmap_clu_len == bitmap_clu_len) {
416 finfo.clu_byte_off -= bitmap_clu_len;
417 finfo.total_clu_cnt = total_clu_cnt;
418 finfo.bitmap_byte_off -= bitmap_clu_len;
419 finfo.bitmap_byte_len = bitmap_byte_len;
422 bitmap_clu_len = new_bitmap_clu_len;
426 static int exfat_build_mkfs_info(struct exfat_blk_dev *bd,
427 struct exfat_user_input *ui)
429 unsigned long long total_clu_cnt;
432 if (ui->boundary_align < bd->sector_size) {
433 exfat_err("boundary alignment is too small (min %d)\n",
437 finfo.fat_byte_off = round_up(bd->offset + 24 * bd->sector_size,
438 ui->boundary_align) - bd->offset;
439 finfo.fat_byte_len = round_up((bd->num_clusters * sizeof(int)),
441 finfo.clu_byte_off = round_up(bd->offset + finfo.fat_byte_off +
442 finfo.fat_byte_len, ui->boundary_align) - bd->offset;
443 if (bd->size <= finfo.clu_byte_off) {
444 exfat_err("boundary alignment is too big\n");
447 total_clu_cnt = (bd->size - finfo.clu_byte_off) / ui->cluster_size;
448 if (total_clu_cnt > EXFAT_MAX_NUM_CLUSTER) {
449 exfat_err("cluster size is too small\n");
452 finfo.total_clu_cnt = (unsigned int) total_clu_cnt;
454 finfo.bitmap_byte_off = finfo.clu_byte_off;
455 finfo.bitmap_byte_len = round_up(finfo.total_clu_cnt, 8) / 8;
457 exfat_pack_bitmap(ui);
458 clu_len = round_up(finfo.bitmap_byte_len, ui->cluster_size);
460 finfo.ut_start_clu = EXFAT_FIRST_CLUSTER + clu_len / ui->cluster_size;
461 finfo.ut_byte_off = finfo.bitmap_byte_off + clu_len;
462 finfo.ut_byte_len = EXFAT_UPCASE_TABLE_SIZE;
463 clu_len = round_up(finfo.ut_byte_len, ui->cluster_size);
465 finfo.root_start_clu = finfo.ut_start_clu + clu_len / ui->cluster_size;
466 finfo.root_byte_off = finfo.ut_byte_off + clu_len;
467 finfo.root_byte_len = sizeof(struct exfat_dentry) * 3;
468 finfo.volume_serial = get_new_serial();
473 static int exfat_zero_out_disk(struct exfat_blk_dev *bd,
474 struct exfat_user_input *ui)
477 unsigned long long total_written = 0;
479 unsigned int chunk_size = ui->cluster_size;
480 unsigned long long size;
483 size = finfo.root_byte_off + chunk_size;
487 buf = malloc(chunk_size);
491 memset(buf, 0, chunk_size);
492 lseek(bd->dev_fd, 0, SEEK_SET);
495 nbytes = write(bd->dev_fd, buf, chunk_size);
498 exfat_err("write failed(errno : %d)\n", errno);
501 total_written += nbytes;
502 } while (total_written < size);
505 exfat_debug("zero out written size : %llu, disk size : %llu\n",
506 total_written, bd->size);
510 static int make_exfat(struct exfat_blk_dev *bd, struct exfat_user_input *ui)
514 exfat_info("Creating exFAT filesystem(%s, cluster size=%u)\n\n",
515 ui->dev_name, ui->cluster_size);
517 exfat_info("Writing volume boot record: ");
518 ret = exfat_create_volume_boot_record(bd, ui, 0);
519 exfat_info("%s\n", ret ? "failed" : "done");
523 exfat_info("Writing backup volume boot record: ");
525 ret = exfat_create_volume_boot_record(bd, ui, 1);
526 exfat_info("%s\n", ret ? "failed" : "done");
530 exfat_info("Fat table creation: ");
531 ret = exfat_create_fat_table(bd, ui);
532 exfat_info("%s\n", ret ? "failed" : "done");
536 exfat_info("Allocation bitmap creation: ");
537 ret = exfat_create_bitmap(bd);
538 exfat_info("%s\n", ret ? "failed" : "done");
542 exfat_info("Upcase table creation: ");
543 ret = exfat_create_upcase_table(bd);
544 exfat_info("%s\n", ret ? "failed" : "done");
548 exfat_info("Writing root directory entry: ");
549 ret = exfat_create_root_dir(bd, ui);
550 exfat_info("%s\n", ret ? "failed" : "done");
557 static long long parse_size(const char *size)
560 unsigned long long byte_size = strtoull(size, &data_unit, 0);
562 switch (*data_unit) {
574 exfat_err("Wrong unit input('%c') for size\n",
582 int main(int argc, char *argv[])
585 int ret = EXIT_FAILURE;
586 struct exfat_blk_dev bd;
587 struct exfat_user_input ui;
588 bool version_only = false;
590 init_user_input(&ui);
592 if (!setlocale(LC_CTYPE, ""))
593 exfat_err("failed to init locale/codeset\n");
596 while ((c = getopt_long(argc, argv, "n:L:c:b:fVvh", opts, NULL)) != EOF)
599 * Make 'n' option fallthrough to 'L' option for for backward
600 * compatibility with old utils.
605 ret = exfat_utf16_enc(optarg,
606 ui.volume_label, sizeof(ui.volume_label));
610 ui.volume_label_len = ret;
614 ret = parse_size(optarg);
617 else if (ret & (ret - 1)) {
618 exfat_err("cluster size(%d) is not a power of 2)\n",
621 } else if (ret > EXFAT_MAX_CLUSTER_SIZE) {
622 exfat_err("cluster size(%d) exceeds max cluster size(%d)\n",
623 ui.cluster_size, EXFAT_MAX_CLUSTER_SIZE);
626 ui.cluster_size = ret;
629 ret = parse_size(optarg);
632 else if (ret & (ret - 1)) {
633 exfat_err("boundary align(%d) is not a power of 2)\n",
637 ui.boundary_align = ret;
640 ui.pack_bitmap = true;
649 print_level = EXFAT_DEBUG;
661 if (argc - optind != 1) {
665 memset(ui.dev_name, 0, sizeof(ui.dev_name));
666 snprintf(ui.dev_name, sizeof(ui.dev_name), "%s", argv[optind]);
668 ret = exfat_get_blk_dev_info(&ui, &bd);
672 ret = exfat_build_mkfs_info(&bd, &ui);
676 ret = exfat_zero_out_disk(&bd, &ui);
680 ret = make_exfat(&bd, &ui);
684 exfat_info("Synchronizing...\n");
685 ret = fsync(bd.dev_fd);
690 exfat_info("\nexFAT format complete!\n");
692 exfat_info("\nexFAT format fail!\n");