1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd. 4 */ 5 6 #include <linux/fs_context.h> 7 #include <linux/fs_parser.h> 8 #include <linux/module.h> 9 #include <linux/init.h> 10 #include <linux/time.h> 11 #include <linux/mount.h> 12 #include <linux/cred.h> 13 #include <linux/statfs.h> 14 #include <linux/seq_file.h> 15 #include <linux/blkdev.h> 16 #include <linux/fs_struct.h> 17 #include <linux/iversion.h> 18 #include <linux/nls.h> 19 #include <linux/buffer_head.h> 20 #include <linux/magic.h> 21 22 #include "exfat_raw.h" 23 #include "exfat_fs.h" 24 25 static char exfat_default_iocharset[] = CONFIG_EXFAT_DEFAULT_IOCHARSET; 26 static struct kmem_cache *exfat_inode_cachep; 27 28 static void exfat_free_iocharset(struct exfat_sb_info *sbi) 29 { 30 if (sbi->options.iocharset != exfat_default_iocharset) 31 kfree(sbi->options.iocharset); 32 } 33 34 static void exfat_put_super(struct super_block *sb) 35 { 36 struct exfat_sb_info *sbi = EXFAT_SB(sb); 37 38 mutex_lock(&sbi->s_lock); 39 exfat_free_bitmap(sbi); 40 brelse(sbi->boot_bh); 41 mutex_unlock(&sbi->s_lock); 42 43 unload_nls(sbi->nls_io); 44 exfat_free_upcase_table(sbi); 45 } 46 47 static int exfat_sync_fs(struct super_block *sb, int wait) 48 { 49 struct exfat_sb_info *sbi = EXFAT_SB(sb); 50 int err = 0; 51 52 if (!wait) 53 return 0; 54 55 /* If there are some dirty buffers in the bdev inode */ 56 mutex_lock(&sbi->s_lock); 57 sync_blockdev(sb->s_bdev); 58 if (exfat_clear_volume_dirty(sb)) 59 err = -EIO; 60 mutex_unlock(&sbi->s_lock); 61 return err; 62 } 63 64 static int exfat_statfs(struct dentry *dentry, struct kstatfs *buf) 65 { 66 struct super_block *sb = dentry->d_sb; 67 struct exfat_sb_info *sbi = EXFAT_SB(sb); 68 unsigned long long id = huge_encode_dev(sb->s_bdev->bd_dev); 69 70 if (sbi->used_clusters == EXFAT_CLUSTERS_UNTRACKED) { 71 mutex_lock(&sbi->s_lock); 72 if (exfat_count_used_clusters(sb, &sbi->used_clusters)) { 73 mutex_unlock(&sbi->s_lock); 74 return -EIO; 75 } 76 mutex_unlock(&sbi->s_lock); 77 } 78 79 buf->f_type = sb->s_magic; 80 buf->f_bsize = sbi->cluster_size; 81 buf->f_blocks = sbi->num_clusters - 2; /* clu 0 & 1 */ 82 buf->f_bfree = buf->f_blocks - sbi->used_clusters; 83 buf->f_bavail = buf->f_bfree; 84 buf->f_fsid = u64_to_fsid(id); 85 /* Unicode utf16 255 characters */ 86 buf->f_namelen = EXFAT_MAX_FILE_LEN * NLS_MAX_CHARSET_SIZE; 87 return 0; 88 } 89 90 static int exfat_set_vol_flags(struct super_block *sb, unsigned short new_flags) 91 { 92 struct exfat_sb_info *sbi = EXFAT_SB(sb); 93 struct boot_sector *p_boot = (struct boot_sector *)sbi->boot_bh->b_data; 94 95 /* retain persistent-flags */ 96 new_flags |= sbi->vol_flags_persistent; 97 98 /* flags are not changed */ 99 if (sbi->vol_flags == new_flags) 100 return 0; 101 102 sbi->vol_flags = new_flags; 103 104 /* skip updating volume dirty flag, 105 * if this volume has been mounted with read-only 106 */ 107 if (sb_rdonly(sb)) 108 return 0; 109 110 p_boot->vol_flags = cpu_to_le16(new_flags); 111 112 set_buffer_uptodate(sbi->boot_bh); 113 mark_buffer_dirty(sbi->boot_bh); 114 115 __sync_dirty_buffer(sbi->boot_bh, REQ_SYNC | REQ_FUA | REQ_PREFLUSH); 116 117 return 0; 118 } 119 120 int exfat_set_volume_dirty(struct super_block *sb) 121 { 122 struct exfat_sb_info *sbi = EXFAT_SB(sb); 123 124 return exfat_set_vol_flags(sb, sbi->vol_flags | VOLUME_DIRTY); 125 } 126 127 int exfat_clear_volume_dirty(struct super_block *sb) 128 { 129 struct exfat_sb_info *sbi = EXFAT_SB(sb); 130 131 return exfat_set_vol_flags(sb, sbi->vol_flags & ~VOLUME_DIRTY); 132 } 133 134 static int exfat_show_options(struct seq_file *m, struct dentry *root) 135 { 136 struct super_block *sb = root->d_sb; 137 struct exfat_sb_info *sbi = EXFAT_SB(sb); 138 struct exfat_mount_options *opts = &sbi->options; 139 140 /* Show partition info */ 141 if (!uid_eq(opts->fs_uid, GLOBAL_ROOT_UID)) 142 seq_printf(m, ",uid=%u", 143 from_kuid_munged(&init_user_ns, opts->fs_uid)); 144 if (!gid_eq(opts->fs_gid, GLOBAL_ROOT_GID)) 145 seq_printf(m, ",gid=%u", 146 from_kgid_munged(&init_user_ns, opts->fs_gid)); 147 seq_printf(m, ",fmask=%04o,dmask=%04o", opts->fs_fmask, opts->fs_dmask); 148 if (opts->allow_utime) 149 seq_printf(m, ",allow_utime=%04o", opts->allow_utime); 150 if (opts->utf8) 151 seq_puts(m, ",iocharset=utf8"); 152 else if (sbi->nls_io) 153 seq_printf(m, ",iocharset=%s", sbi->nls_io->charset); 154 if (opts->errors == EXFAT_ERRORS_CONT) 155 seq_puts(m, ",errors=continue"); 156 else if (opts->errors == EXFAT_ERRORS_PANIC) 157 seq_puts(m, ",errors=panic"); 158 else 159 seq_puts(m, ",errors=remount-ro"); 160 if (opts->discard) 161 seq_puts(m, ",discard"); 162 if (opts->keep_last_dots) 163 seq_puts(m, ",keep_last_dots"); 164 if (opts->sys_tz) 165 seq_puts(m, ",sys_tz"); 166 else if (opts->time_offset) 167 seq_printf(m, ",time_offset=%d", opts->time_offset); 168 if (opts->zero_size_dir) 169 seq_puts(m, ",zero_size_dir"); 170 return 0; 171 } 172 173 static struct inode *exfat_alloc_inode(struct super_block *sb) 174 { 175 struct exfat_inode_info *ei; 176 177 ei = alloc_inode_sb(sb, exfat_inode_cachep, GFP_NOFS); 178 if (!ei) 179 return NULL; 180 181 init_rwsem(&ei->truncate_lock); 182 return &ei->vfs_inode; 183 } 184 185 static void exfat_free_inode(struct inode *inode) 186 { 187 kmem_cache_free(exfat_inode_cachep, EXFAT_I(inode)); 188 } 189 190 static const struct super_operations exfat_sops = { 191 .alloc_inode = exfat_alloc_inode, 192 .free_inode = exfat_free_inode, 193 .write_inode = exfat_write_inode, 194 .evict_inode = exfat_evict_inode, 195 .put_super = exfat_put_super, 196 .sync_fs = exfat_sync_fs, 197 .statfs = exfat_statfs, 198 .show_options = exfat_show_options, 199 }; 200 201 enum { 202 Opt_uid, 203 Opt_gid, 204 Opt_umask, 205 Opt_dmask, 206 Opt_fmask, 207 Opt_allow_utime, 208 Opt_charset, 209 Opt_errors, 210 Opt_discard, 211 Opt_keep_last_dots, 212 Opt_sys_tz, 213 Opt_time_offset, 214 Opt_zero_size_dir, 215 216 /* Deprecated options */ 217 Opt_utf8, 218 Opt_debug, 219 Opt_namecase, 220 Opt_codepage, 221 }; 222 223 static const struct constant_table exfat_param_enums[] = { 224 { "continue", EXFAT_ERRORS_CONT }, 225 { "panic", EXFAT_ERRORS_PANIC }, 226 { "remount-ro", EXFAT_ERRORS_RO }, 227 {} 228 }; 229 230 static const struct fs_parameter_spec exfat_parameters[] = { 231 fsparam_u32("uid", Opt_uid), 232 fsparam_u32("gid", Opt_gid), 233 fsparam_u32oct("umask", Opt_umask), 234 fsparam_u32oct("dmask", Opt_dmask), 235 fsparam_u32oct("fmask", Opt_fmask), 236 fsparam_u32oct("allow_utime", Opt_allow_utime), 237 fsparam_string("iocharset", Opt_charset), 238 fsparam_enum("errors", Opt_errors, exfat_param_enums), 239 fsparam_flag("discard", Opt_discard), 240 fsparam_flag("keep_last_dots", Opt_keep_last_dots), 241 fsparam_flag("sys_tz", Opt_sys_tz), 242 fsparam_s32("time_offset", Opt_time_offset), 243 fsparam_flag("zero_size_dir", Opt_zero_size_dir), 244 __fsparam(NULL, "utf8", Opt_utf8, fs_param_deprecated, 245 NULL), 246 __fsparam(NULL, "debug", Opt_debug, fs_param_deprecated, 247 NULL), 248 __fsparam(fs_param_is_u32, "namecase", Opt_namecase, 249 fs_param_deprecated, NULL), 250 __fsparam(fs_param_is_u32, "codepage", Opt_codepage, 251 fs_param_deprecated, NULL), 252 {} 253 }; 254 255 static int exfat_parse_param(struct fs_context *fc, struct fs_parameter *param) 256 { 257 struct exfat_sb_info *sbi = fc->s_fs_info; 258 struct exfat_mount_options *opts = &sbi->options; 259 struct fs_parse_result result; 260 int opt; 261 262 opt = fs_parse(fc, exfat_parameters, param, &result); 263 if (opt < 0) 264 return opt; 265 266 switch (opt) { 267 case Opt_uid: 268 opts->fs_uid = make_kuid(current_user_ns(), result.uint_32); 269 break; 270 case Opt_gid: 271 opts->fs_gid = make_kgid(current_user_ns(), result.uint_32); 272 break; 273 case Opt_umask: 274 opts->fs_fmask = result.uint_32; 275 opts->fs_dmask = result.uint_32; 276 break; 277 case Opt_dmask: 278 opts->fs_dmask = result.uint_32; 279 break; 280 case Opt_fmask: 281 opts->fs_fmask = result.uint_32; 282 break; 283 case Opt_allow_utime: 284 opts->allow_utime = result.uint_32 & 0022; 285 break; 286 case Opt_charset: 287 exfat_free_iocharset(sbi); 288 opts->iocharset = param->string; 289 param->string = NULL; 290 break; 291 case Opt_errors: 292 opts->errors = result.uint_32; 293 break; 294 case Opt_discard: 295 opts->discard = 1; 296 break; 297 case Opt_keep_last_dots: 298 opts->keep_last_dots = 1; 299 break; 300 case Opt_sys_tz: 301 opts->sys_tz = 1; 302 break; 303 case Opt_time_offset: 304 /* 305 * Make the limit 24 just in case someone invents something 306 * unusual. 307 */ 308 if (result.int_32 < -24 * 60 || result.int_32 > 24 * 60) 309 return -EINVAL; 310 opts->time_offset = result.int_32; 311 break; 312 case Opt_zero_size_dir: 313 opts->zero_size_dir = true; 314 break; 315 case Opt_utf8: 316 case Opt_debug: 317 case Opt_namecase: 318 case Opt_codepage: 319 break; 320 default: 321 return -EINVAL; 322 } 323 324 return 0; 325 } 326 327 static void exfat_hash_init(struct super_block *sb) 328 { 329 struct exfat_sb_info *sbi = EXFAT_SB(sb); 330 int i; 331 332 spin_lock_init(&sbi->inode_hash_lock); 333 for (i = 0; i < EXFAT_HASH_SIZE; i++) 334 INIT_HLIST_HEAD(&sbi->inode_hashtable[i]); 335 } 336 337 static int exfat_read_root(struct inode *inode) 338 { 339 struct super_block *sb = inode->i_sb; 340 struct exfat_sb_info *sbi = EXFAT_SB(sb); 341 struct exfat_inode_info *ei = EXFAT_I(inode); 342 struct exfat_chain cdir; 343 int num_subdirs, num_clu = 0; 344 345 exfat_chain_set(&ei->dir, sbi->root_dir, 0, ALLOC_FAT_CHAIN); 346 ei->entry = -1; 347 ei->start_clu = sbi->root_dir; 348 ei->flags = ALLOC_FAT_CHAIN; 349 ei->type = TYPE_DIR; 350 ei->version = 0; 351 ei->hint_bmap.off = EXFAT_EOF_CLUSTER; 352 ei->hint_stat.eidx = 0; 353 ei->hint_stat.clu = sbi->root_dir; 354 ei->hint_femp.eidx = EXFAT_HINT_NONE; 355 356 exfat_chain_set(&cdir, sbi->root_dir, 0, ALLOC_FAT_CHAIN); 357 if (exfat_count_num_clusters(sb, &cdir, &num_clu)) 358 return -EIO; 359 i_size_write(inode, num_clu << sbi->cluster_size_bits); 360 361 num_subdirs = exfat_count_dir_entries(sb, &cdir); 362 if (num_subdirs < 0) 363 return -EIO; 364 set_nlink(inode, num_subdirs + EXFAT_MIN_SUBDIR); 365 366 inode->i_uid = sbi->options.fs_uid; 367 inode->i_gid = sbi->options.fs_gid; 368 inode_inc_iversion(inode); 369 inode->i_generation = 0; 370 inode->i_mode = exfat_make_mode(sbi, EXFAT_ATTR_SUBDIR, 0777); 371 inode->i_op = &exfat_dir_inode_operations; 372 inode->i_fop = &exfat_dir_operations; 373 374 inode->i_blocks = round_up(i_size_read(inode), sbi->cluster_size) >> 9; 375 ei->i_pos = ((loff_t)sbi->root_dir << 32) | 0xffffffff; 376 ei->i_size_aligned = i_size_read(inode); 377 ei->i_size_ondisk = i_size_read(inode); 378 379 exfat_save_attr(inode, EXFAT_ATTR_SUBDIR); 380 ei->i_crtime = simple_inode_init_ts(inode); 381 exfat_truncate_inode_atime(inode); 382 return 0; 383 } 384 385 static int exfat_calibrate_blocksize(struct super_block *sb, int logical_sect) 386 { 387 struct exfat_sb_info *sbi = EXFAT_SB(sb); 388 389 if (!is_power_of_2(logical_sect)) { 390 exfat_err(sb, "bogus logical sector size %u", logical_sect); 391 return -EIO; 392 } 393 394 if (logical_sect < sb->s_blocksize) { 395 exfat_err(sb, "logical sector size too small for device (logical sector size = %u)", 396 logical_sect); 397 return -EIO; 398 } 399 400 if (logical_sect > sb->s_blocksize) { 401 brelse(sbi->boot_bh); 402 sbi->boot_bh = NULL; 403 404 if (!sb_set_blocksize(sb, logical_sect)) { 405 exfat_err(sb, "unable to set blocksize %u", 406 logical_sect); 407 return -EIO; 408 } 409 sbi->boot_bh = sb_bread(sb, 0); 410 if (!sbi->boot_bh) { 411 exfat_err(sb, "unable to read boot sector (logical sector size = %lu)", 412 sb->s_blocksize); 413 return -EIO; 414 } 415 } 416 return 0; 417 } 418 419 static int exfat_read_boot_sector(struct super_block *sb) 420 { 421 struct boot_sector *p_boot; 422 struct exfat_sb_info *sbi = EXFAT_SB(sb); 423 424 /* set block size to read super block */ 425 sb_min_blocksize(sb, 512); 426 427 /* read boot sector */ 428 sbi->boot_bh = sb_bread(sb, 0); 429 if (!sbi->boot_bh) { 430 exfat_err(sb, "unable to read boot sector"); 431 return -EIO; 432 } 433 p_boot = (struct boot_sector *)sbi->boot_bh->b_data; 434 435 /* check the validity of BOOT */ 436 if (le16_to_cpu((p_boot->signature)) != BOOT_SIGNATURE) { 437 exfat_err(sb, "invalid boot record signature"); 438 return -EINVAL; 439 } 440 441 if (memcmp(p_boot->fs_name, STR_EXFAT, BOOTSEC_FS_NAME_LEN)) { 442 exfat_err(sb, "invalid fs_name"); /* fs_name may unprintable */ 443 return -EINVAL; 444 } 445 446 /* 447 * must_be_zero field must be filled with zero to prevent mounting 448 * from FAT volume. 449 */ 450 if (memchr_inv(p_boot->must_be_zero, 0, sizeof(p_boot->must_be_zero))) 451 return -EINVAL; 452 453 if (p_boot->num_fats != 1 && p_boot->num_fats != 2) { 454 exfat_err(sb, "bogus number of FAT structure"); 455 return -EINVAL; 456 } 457 458 /* 459 * sect_size_bits could be at least 9 and at most 12. 460 */ 461 if (p_boot->sect_size_bits < EXFAT_MIN_SECT_SIZE_BITS || 462 p_boot->sect_size_bits > EXFAT_MAX_SECT_SIZE_BITS) { 463 exfat_err(sb, "bogus sector size bits : %u", 464 p_boot->sect_size_bits); 465 return -EINVAL; 466 } 467 468 /* 469 * sect_per_clus_bits could be at least 0 and at most 25 - sect_size_bits. 470 */ 471 if (p_boot->sect_per_clus_bits > EXFAT_MAX_SECT_PER_CLUS_BITS(p_boot)) { 472 exfat_err(sb, "bogus sectors bits per cluster : %u", 473 p_boot->sect_per_clus_bits); 474 return -EINVAL; 475 } 476 477 sbi->sect_per_clus = 1 << p_boot->sect_per_clus_bits; 478 sbi->sect_per_clus_bits = p_boot->sect_per_clus_bits; 479 sbi->cluster_size_bits = p_boot->sect_per_clus_bits + 480 p_boot->sect_size_bits; 481 sbi->cluster_size = 1 << sbi->cluster_size_bits; 482 sbi->num_FAT_sectors = le32_to_cpu(p_boot->fat_length); 483 sbi->FAT1_start_sector = le32_to_cpu(p_boot->fat_offset); 484 sbi->FAT2_start_sector = le32_to_cpu(p_boot->fat_offset); 485 if (p_boot->num_fats == 2) 486 sbi->FAT2_start_sector += sbi->num_FAT_sectors; 487 sbi->data_start_sector = le32_to_cpu(p_boot->clu_offset); 488 sbi->num_sectors = le64_to_cpu(p_boot->vol_length); 489 /* because the cluster index starts with 2 */ 490 sbi->num_clusters = le32_to_cpu(p_boot->clu_count) + 491 EXFAT_RESERVED_CLUSTERS; 492 493 sbi->root_dir = le32_to_cpu(p_boot->root_cluster); 494 sbi->dentries_per_clu = 1 << 495 (sbi->cluster_size_bits - DENTRY_SIZE_BITS); 496 497 sbi->vol_flags = le16_to_cpu(p_boot->vol_flags); 498 sbi->vol_flags_persistent = sbi->vol_flags & (VOLUME_DIRTY | MEDIA_FAILURE); 499 sbi->clu_srch_ptr = EXFAT_FIRST_CLUSTER; 500 sbi->used_clusters = EXFAT_CLUSTERS_UNTRACKED; 501 502 /* check consistencies */ 503 if ((u64)sbi->num_FAT_sectors << p_boot->sect_size_bits < 504 (u64)sbi->num_clusters * 4) { 505 exfat_err(sb, "bogus fat length"); 506 return -EINVAL; 507 } 508 509 if (sbi->data_start_sector < 510 (u64)sbi->FAT1_start_sector + 511 (u64)sbi->num_FAT_sectors * p_boot->num_fats) { 512 exfat_err(sb, "bogus data start sector"); 513 return -EINVAL; 514 } 515 516 if (sbi->vol_flags & VOLUME_DIRTY) 517 exfat_warn(sb, "Volume was not properly unmounted. Some data may be corrupt. Please run fsck."); 518 if (sbi->vol_flags & MEDIA_FAILURE) 519 exfat_warn(sb, "Medium has reported failures. Some data may be lost."); 520 521 /* exFAT file size is limited by a disk volume size */ 522 sb->s_maxbytes = (u64)(sbi->num_clusters - EXFAT_RESERVED_CLUSTERS) << 523 sbi->cluster_size_bits; 524 525 /* check logical sector size */ 526 if (exfat_calibrate_blocksize(sb, 1 << p_boot->sect_size_bits)) 527 return -EIO; 528 529 return 0; 530 } 531 532 static int exfat_verify_boot_region(struct super_block *sb) 533 { 534 struct buffer_head *bh = NULL; 535 u32 chksum = 0; 536 __le32 *p_sig, *p_chksum; 537 int sn, i; 538 539 /* read boot sector sub-regions */ 540 for (sn = 0; sn < 11; sn++) { 541 bh = sb_bread(sb, sn); 542 if (!bh) 543 return -EIO; 544 545 if (sn != 0 && sn <= 8) { 546 /* extended boot sector sub-regions */ 547 p_sig = (__le32 *)&bh->b_data[sb->s_blocksize - 4]; 548 if (le32_to_cpu(*p_sig) != EXBOOT_SIGNATURE) 549 exfat_warn(sb, "Invalid exboot-signature(sector = %d): 0x%08x", 550 sn, le32_to_cpu(*p_sig)); 551 } 552 553 chksum = exfat_calc_chksum32(bh->b_data, sb->s_blocksize, 554 chksum, sn ? CS_DEFAULT : CS_BOOT_SECTOR); 555 brelse(bh); 556 } 557 558 /* boot checksum sub-regions */ 559 bh = sb_bread(sb, sn); 560 if (!bh) 561 return -EIO; 562 563 for (i = 0; i < sb->s_blocksize; i += sizeof(u32)) { 564 p_chksum = (__le32 *)&bh->b_data[i]; 565 if (le32_to_cpu(*p_chksum) != chksum) { 566 exfat_err(sb, "Invalid boot checksum (boot checksum : 0x%08x, checksum : 0x%08x)", 567 le32_to_cpu(*p_chksum), chksum); 568 brelse(bh); 569 return -EINVAL; 570 } 571 } 572 brelse(bh); 573 return 0; 574 } 575 576 /* mount the file system volume */ 577 static int __exfat_fill_super(struct super_block *sb) 578 { 579 int ret; 580 struct exfat_sb_info *sbi = EXFAT_SB(sb); 581 582 ret = exfat_read_boot_sector(sb); 583 if (ret) { 584 exfat_err(sb, "failed to read boot sector"); 585 goto free_bh; 586 } 587 588 ret = exfat_verify_boot_region(sb); 589 if (ret) { 590 exfat_err(sb, "invalid boot region"); 591 goto free_bh; 592 } 593 594 ret = exfat_create_upcase_table(sb); 595 if (ret) { 596 exfat_err(sb, "failed to load upcase table"); 597 goto free_bh; 598 } 599 600 ret = exfat_load_bitmap(sb); 601 if (ret) { 602 exfat_err(sb, "failed to load alloc-bitmap"); 603 goto free_upcase_table; 604 } 605 606 ret = exfat_count_used_clusters(sb, &sbi->used_clusters); 607 if (ret) { 608 exfat_err(sb, "failed to scan clusters"); 609 goto free_alloc_bitmap; 610 } 611 612 return 0; 613 614 free_alloc_bitmap: 615 exfat_free_bitmap(sbi); 616 free_upcase_table: 617 exfat_free_upcase_table(sbi); 618 free_bh: 619 brelse(sbi->boot_bh); 620 return ret; 621 } 622 623 static int exfat_fill_super(struct super_block *sb, struct fs_context *fc) 624 { 625 struct exfat_sb_info *sbi = sb->s_fs_info; 626 struct exfat_mount_options *opts = &sbi->options; 627 struct inode *root_inode; 628 int err; 629 630 if (opts->allow_utime == (unsigned short)-1) 631 opts->allow_utime = ~opts->fs_dmask & 0022; 632 633 if (opts->discard && !bdev_max_discard_sectors(sb->s_bdev)) { 634 exfat_warn(sb, "mounting with \"discard\" option, but the device does not support discard"); 635 opts->discard = 0; 636 } 637 638 sb->s_flags |= SB_NODIRATIME; 639 sb->s_magic = EXFAT_SUPER_MAGIC; 640 sb->s_op = &exfat_sops; 641 642 sb->s_time_gran = 10 * NSEC_PER_MSEC; 643 sb->s_time_min = EXFAT_MIN_TIMESTAMP_SECS; 644 sb->s_time_max = EXFAT_MAX_TIMESTAMP_SECS; 645 646 err = __exfat_fill_super(sb); 647 if (err) { 648 exfat_err(sb, "failed to recognize exfat type"); 649 goto check_nls_io; 650 } 651 652 /* set up enough so that it can read an inode */ 653 exfat_hash_init(sb); 654 655 if (!strcmp(sbi->options.iocharset, "utf8")) 656 opts->utf8 = 1; 657 else { 658 sbi->nls_io = load_nls(sbi->options.iocharset); 659 if (!sbi->nls_io) { 660 exfat_err(sb, "IO charset %s not found", 661 sbi->options.iocharset); 662 err = -EINVAL; 663 goto free_table; 664 } 665 } 666 667 if (sbi->options.utf8) 668 sb->s_d_op = &exfat_utf8_dentry_ops; 669 else 670 sb->s_d_op = &exfat_dentry_ops; 671 672 root_inode = new_inode(sb); 673 if (!root_inode) { 674 exfat_err(sb, "failed to allocate root inode"); 675 err = -ENOMEM; 676 goto free_table; 677 } 678 679 root_inode->i_ino = EXFAT_ROOT_INO; 680 inode_set_iversion(root_inode, 1); 681 err = exfat_read_root(root_inode); 682 if (err) { 683 exfat_err(sb, "failed to initialize root inode"); 684 goto put_inode; 685 } 686 687 exfat_hash_inode(root_inode, EXFAT_I(root_inode)->i_pos); 688 insert_inode_hash(root_inode); 689 690 sb->s_root = d_make_root(root_inode); 691 if (!sb->s_root) { 692 exfat_err(sb, "failed to get the root dentry"); 693 err = -ENOMEM; 694 goto free_table; 695 } 696 697 return 0; 698 699 put_inode: 700 iput(root_inode); 701 sb->s_root = NULL; 702 703 free_table: 704 exfat_free_upcase_table(sbi); 705 exfat_free_bitmap(sbi); 706 brelse(sbi->boot_bh); 707 708 check_nls_io: 709 unload_nls(sbi->nls_io); 710 return err; 711 } 712 713 static int exfat_get_tree(struct fs_context *fc) 714 { 715 return get_tree_bdev(fc, exfat_fill_super); 716 } 717 718 static void exfat_free_sbi(struct exfat_sb_info *sbi) 719 { 720 exfat_free_iocharset(sbi); 721 kfree(sbi); 722 } 723 724 static void exfat_free(struct fs_context *fc) 725 { 726 struct exfat_sb_info *sbi = fc->s_fs_info; 727 728 if (sbi) 729 exfat_free_sbi(sbi); 730 } 731 732 static int exfat_reconfigure(struct fs_context *fc) 733 { 734 fc->sb_flags |= SB_NODIRATIME; 735 736 /* volume flag will be updated in exfat_sync_fs */ 737 sync_filesystem(fc->root->d_sb); 738 return 0; 739 } 740 741 static const struct fs_context_operations exfat_context_ops = { 742 .parse_param = exfat_parse_param, 743 .get_tree = exfat_get_tree, 744 .free = exfat_free, 745 .reconfigure = exfat_reconfigure, 746 }; 747 748 static int exfat_init_fs_context(struct fs_context *fc) 749 { 750 struct exfat_sb_info *sbi; 751 752 sbi = kzalloc(sizeof(struct exfat_sb_info), GFP_KERNEL); 753 if (!sbi) 754 return -ENOMEM; 755 756 mutex_init(&sbi->s_lock); 757 mutex_init(&sbi->bitmap_lock); 758 ratelimit_state_init(&sbi->ratelimit, DEFAULT_RATELIMIT_INTERVAL, 759 DEFAULT_RATELIMIT_BURST); 760 761 sbi->options.fs_uid = current_uid(); 762 sbi->options.fs_gid = current_gid(); 763 sbi->options.fs_fmask = current->fs->umask; 764 sbi->options.fs_dmask = current->fs->umask; 765 sbi->options.allow_utime = -1; 766 sbi->options.iocharset = exfat_default_iocharset; 767 sbi->options.errors = EXFAT_ERRORS_RO; 768 769 fc->s_fs_info = sbi; 770 fc->ops = &exfat_context_ops; 771 return 0; 772 } 773 774 static void exfat_kill_sb(struct super_block *sb) 775 { 776 struct exfat_sb_info *sbi = sb->s_fs_info; 777 778 kill_block_super(sb); 779 if (sbi) 780 exfat_free_sbi(sbi); 781 } 782 783 static struct file_system_type exfat_fs_type = { 784 .owner = THIS_MODULE, 785 .name = "exfat", 786 .init_fs_context = exfat_init_fs_context, 787 .parameters = exfat_parameters, 788 .kill_sb = exfat_kill_sb, 789 .fs_flags = FS_REQUIRES_DEV, 790 }; 791 792 static void exfat_inode_init_once(void *foo) 793 { 794 struct exfat_inode_info *ei = (struct exfat_inode_info *)foo; 795 796 spin_lock_init(&ei->cache_lru_lock); 797 ei->nr_caches = 0; 798 ei->cache_valid_id = EXFAT_CACHE_VALID + 1; 799 INIT_LIST_HEAD(&ei->cache_lru); 800 INIT_HLIST_NODE(&ei->i_hash_fat); 801 inode_init_once(&ei->vfs_inode); 802 } 803 804 static int __init init_exfat_fs(void) 805 { 806 int err; 807 808 err = exfat_cache_init(); 809 if (err) 810 return err; 811 812 exfat_inode_cachep = kmem_cache_create("exfat_inode_cache", 813 sizeof(struct exfat_inode_info), 814 0, SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, 815 exfat_inode_init_once); 816 if (!exfat_inode_cachep) { 817 err = -ENOMEM; 818 goto shutdown_cache; 819 } 820 821 err = register_filesystem(&exfat_fs_type); 822 if (err) 823 goto destroy_cache; 824 825 return 0; 826 827 destroy_cache: 828 kmem_cache_destroy(exfat_inode_cachep); 829 shutdown_cache: 830 exfat_cache_shutdown(); 831 return err; 832 } 833 834 static void __exit exit_exfat_fs(void) 835 { 836 /* 837 * Make sure all delayed rcu free inodes are flushed before we 838 * destroy cache. 839 */ 840 rcu_barrier(); 841 kmem_cache_destroy(exfat_inode_cachep); 842 unregister_filesystem(&exfat_fs_type); 843 exfat_cache_shutdown(); 844 } 845 846 module_init(init_exfat_fs); 847 module_exit(exit_exfat_fs); 848 849 MODULE_ALIAS_FS("exfat"); 850 MODULE_LICENSE("GPL"); 851 MODULE_DESCRIPTION("exFAT filesystem support"); 852 MODULE_AUTHOR("Samsung Electronics Co., Ltd."); 853