static int setup(struct exfat_dev* dev, int sector_bits, int spc_bits, const char* volume_label, uint32_t volume_serial, uint64_t first_sector) { param.sector_bits = sector_bits; param.first_sector = first_sector; param.volume_size = exfat_get_size(dev); param.spc_bits = setup_spc_bits(sector_bits, spc_bits, param.volume_size); if (param.spc_bits == -1) return 1; if (setup_volume_label(param.volume_label, volume_label) != 0) return 1; param.volume_serial = setup_volume_serial(volume_serial); if (param.volume_serial == 0) return 1; return mkfs(dev, param.volume_size); }
int exfat_mount(struct exfat* ef, const char* spec, const char* options) { int rc; enum exfat_mode mode; exfat_tzset(); memset(ef, 0, sizeof(struct exfat)); parse_options(ef, options); if (match_option(options, "ro")) mode = EXFAT_MODE_RO; else if (match_option(options, "ro_fallback")) mode = EXFAT_MODE_ANY; else mode = EXFAT_MODE_RW; ef->dev = exfat_open(spec, mode); if (ef->dev == NULL) return -EIO; if (exfat_get_mode(ef->dev) == EXFAT_MODE_RO) { if (mode == EXFAT_MODE_ANY) ef->ro = -1; else ef->ro = 1; } ef->sb = malloc(sizeof(struct exfat_super_block)); if (ef->sb == NULL) { exfat_close(ef->dev); exfat_error("failed to allocate memory for the super block"); return -ENOMEM; } memset(ef->sb, 0, sizeof(struct exfat_super_block)); if (exfat_pread(ef->dev, ef->sb, sizeof(struct exfat_super_block), 0) < 0) { exfat_close(ef->dev); free(ef->sb); exfat_error("failed to read boot sector"); return -EIO; } if (memcmp(ef->sb->oem_name, "EXFAT ", 8) != 0) { exfat_close(ef->dev); free(ef->sb); exfat_error("exFAT file system is not found"); return -EIO; } /* sector cannot be smaller than 512 bytes */ if (ef->sb->sector_bits < 9) { exfat_close(ef->dev); exfat_error("too small sector size: 2^%hhd", ef->sb->sector_bits); free(ef->sb); return -EIO; } /* officially exFAT supports cluster size up to 32 MB */ if ((int) ef->sb->sector_bits + (int) ef->sb->spc_bits > 25) { exfat_close(ef->dev); exfat_error("too big cluster size: 2^(%hhd+%hhd)", ef->sb->sector_bits, ef->sb->spc_bits); free(ef->sb); return -EIO; } ef->zero_cluster = malloc(CLUSTER_SIZE(*ef->sb)); if (ef->zero_cluster == NULL) { exfat_close(ef->dev); free(ef->sb); exfat_error("failed to allocate zero sector"); return -ENOMEM; } /* use zero_cluster as a temporary buffer for VBR checksum verification */ if (!verify_vbr_checksum(ef->dev, ef->zero_cluster, SECTOR_SIZE(*ef->sb))) { free(ef->zero_cluster); exfat_close(ef->dev); free(ef->sb); return -EIO; } memset(ef->zero_cluster, 0, CLUSTER_SIZE(*ef->sb)); if (ef->sb->version.major != 1 || ef->sb->version.minor != 0) { free(ef->zero_cluster); exfat_close(ef->dev); exfat_error("unsupported exFAT version: %hhu.%hhu", ef->sb->version.major, ef->sb->version.minor); free(ef->sb); return -EIO; } if (ef->sb->fat_count != 1) { free(ef->zero_cluster); exfat_close(ef->dev); exfat_error("unsupported FAT count: %hhu", ef->sb->fat_count); free(ef->sb); return -EIO; } if (le64_to_cpu(ef->sb->sector_count) * SECTOR_SIZE(*ef->sb) > exfat_get_size(ef->dev)) { /* this can cause I/O errors later but we don't fail mounting to let user rescue data */ exfat_warn("file system is larger than underlying device: " "%"PRIu64" > %"PRIu64, le64_to_cpu(ef->sb->sector_count) * SECTOR_SIZE(*ef->sb), exfat_get_size(ef->dev)); } ef->root = malloc(sizeof(struct exfat_node)); if (ef->root == NULL) { free(ef->zero_cluster); exfat_close(ef->dev); free(ef->sb); exfat_error("failed to allocate root node"); return -ENOMEM; } memset(ef->root, 0, sizeof(struct exfat_node)); ef->root->flags = EXFAT_ATTRIB_DIR; ef->root->start_cluster = le32_to_cpu(ef->sb->rootdir_cluster); ef->root->fptr_cluster = ef->root->start_cluster; ef->root->name[0] = cpu_to_le16('\0'); ef->root->size = rootdir_size(ef); if (ef->root->size == 0) { free(ef->root); free(ef->zero_cluster); exfat_close(ef->dev); free(ef->sb); return -EIO; } /* exFAT does not have time attributes for the root directory */ ef->root->mtime = 0; ef->root->atime = 0; /* always keep at least 1 reference to the root node */ exfat_get_node(ef->root); rc = exfat_cache_directory(ef, ef->root); if (rc != 0) goto error; if (ef->upcase == NULL) { exfat_error("upcase table is not found"); goto error; } if (ef->cmap.chunk == NULL) { exfat_error("clusters bitmap is not found"); goto error; } if (prepare_super_block(ef) != 0) goto error; return 0; error: exfat_put_node(ef, ef->root); exfat_reset_cache(ef); free(ef->root); free(ef->zero_cluster); exfat_close(ef->dev); free(ef->sb); return -EIO; }