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 21 #include "exfat_raw.h" 22 #include "exfat_fs.h" 23 24 static char exfat_default_iocharset[] = CONFIG_EXFAT_DEFAULT_IOCHARSET; 25 static struct kmem_cache *exfat_inode_cachep; 26 27 static void exfat_free_iocharset(struct exfat_sb_info *sbi) 28 { 29 if (sbi->options.iocharset != exfat_default_iocharset) 30 kfree(sbi->options.iocharset); 31 } 32 33 static void exfat_delayed_free(struct rcu_head *p) 34 { 35 struct exfat_sb_info *sbi = container_of(p, struct exfat_sb_info, rcu); 36 37 unload_nls(sbi->nls_io); 38 exfat_free_iocharset(sbi); 39 exfat_free_upcase_table(sbi); 40 kfree(sbi); 41 } 42 43 static void exfat_put_super(struct super_block *sb) 44 { 45 struct exfat_sb_info *sbi = EXFAT_SB(sb); 46 47 mutex_lock(&sbi->s_lock); 48 exfat_free_bitmap(sbi); 49 brelse(sbi->boot_bh); 50 mutex_unlock(&sbi->s_lock); 51 52 call_rcu(&sbi->rcu, exfat_delayed_free); 53 } 54 55 static int exfat_sync_fs(struct super_block *sb, int wait) 56 { 57 struct exfat_sb_info *sbi = EXFAT_SB(sb); 58 int err = 0; 59 60 if (!wait) 61 return 0; 62 63 /* If there are some dirty buffers in the bdev inode */ 64 mutex_lock(&sbi->s_lock); 65 sync_blockdev(sb->s_bdev); 66 if (exfat_clear_volume_dirty(sb)) 67 err = -EIO; 68 mutex_unlock(&sbi->s_lock); 69 return err; 70 } 71 72 static int exfat_statfs(struct dentry *dentry, struct kstatfs *buf) 73 { 74 struct super_block *sb = dentry->d_sb; 75 struct exfat_sb_info *sbi = EXFAT_SB(sb); 76 unsigned long long id = huge_encode_dev(sb->s_bdev->bd_dev); 77 78 if (sbi->used_clusters == EXFAT_CLUSTERS_UNTRACKED) { 79 mutex_lock(&sbi->s_lock); 80 if (exfat_count_used_clusters(sb, &sbi->used_clusters)) { 81 mutex_unlock(&sbi->s_lock); 82 return -EIO; 83 } 84 mutex_unlock(&sbi->s_lock); 85 } 86 87 buf->f_type = sb->s_magic; 88 buf->f_bsize = sbi->cluster_size; 89 buf->f_blocks = sbi->num_clusters - 2; /* clu 0 & 1 */ 90 buf->f_bfree = buf->f_blocks - sbi->used_clusters; 91 buf->f_bavail = buf->f_bfree; 92 buf->f_fsid.val[0] = (unsigned int)id; 93 buf->f_fsid.val[1] = (unsigned int)(id >> 32); 94 /* Unicode utf16 255 characters */ 95 buf->f_namelen = EXFAT_MAX_FILE_LEN * NLS_MAX_CHARSET_SIZE; 96 return 0; 97 } 98 99 static int exfat_set_vol_flags(struct super_block *sb, unsigned short new_flags) 100 { 101 struct exfat_sb_info *sbi = EXFAT_SB(sb); 102 struct boot_sector *p_boot = (struct boot_sector *)sbi->boot_bh->b_data; 103 bool sync; 104 105 /* retain persistent-flags */ 106 new_flags |= sbi->vol_flags_persistent; 107 108 /* flags are not changed */ 109 if (sbi->vol_flags == new_flags) 110 return 0; 111 112 sbi->vol_flags = new_flags; 113 114 /* skip updating volume dirty flag, 115 * if this volume has been mounted with read-only 116 */ 117 if (sb_rdonly(sb)) 118 return 0; 119 120 p_boot->vol_flags = cpu_to_le16(new_flags); 121 122 if ((new_flags & VOLUME_DIRTY) && !buffer_dirty(sbi->boot_bh)) 123 sync = true; 124 else 125 sync = false; 126 127 set_buffer_uptodate(sbi->boot_bh); 128 mark_buffer_dirty(sbi->boot_bh); 129 130 if (sync) 131 sync_dirty_buffer(sbi->boot_bh); 132 return 0; 133 } 134 135 int exfat_set_volume_dirty(struct super_block *sb) 136 { 137 struct exfat_sb_info *sbi = EXFAT_SB(sb); 138 139 return exfat_set_vol_flags(sb, sbi->vol_flags | VOLUME_DIRTY); 140 } 141 142 int exfat_clear_volume_dirty(struct super_block *sb) 143 { 144 struct exfat_sb_info *sbi = EXFAT_SB(sb); 145 146 return exfat_set_vol_flags(sb, sbi->vol_flags & ~VOLUME_DIRTY); 147 } 148 149 static int exfat_show_options(struct seq_file *m, struct dentry *root) 150 { 151 struct super_block *sb = root->d_sb; 152 struct exfat_sb_info *sbi = EXFAT_SB(sb); 153 struct exfat_mount_options *opts = &sbi->options; 154 155 /* Show partition info */ 156 if (!uid_eq(opts->fs_uid, GLOBAL_ROOT_UID)) 157 seq_printf(m, ",uid=%u", 158 from_kuid_munged(&init_user_ns, opts->fs_uid)); 159 if (!gid_eq(opts->fs_gid, GLOBAL_ROOT_GID)) 160 seq_printf(m, ",gid=%u", 161 from_kgid_munged(&init_user_ns, opts->fs_gid)); 162 seq_printf(m, ",fmask=%04o,dmask=%04o", opts->fs_fmask, opts->fs_dmask); 163 if (opts->allow_utime) 164 seq_printf(m, ",allow_utime=%04o", opts->allow_utime); 165 if (opts->utf8) 166 seq_puts(m, ",iocharset=utf8"); 167 else if (sbi->nls_io) 168 seq_printf(m, ",iocharset=%s", sbi->nls_io->charset); 169 if (opts->errors == EXFAT_ERRORS_CONT) 170 seq_puts(m, ",errors=continue"); 171 else if (opts->errors == EXFAT_ERRORS_PANIC) 172 seq_puts(m, ",errors=panic"); 173 else 174 seq_puts(m, ",errors=remount-ro"); 175 if (opts->discard) 176 seq_puts(m, ",discard"); 177 if (opts->time_offset) 178 seq_printf(m, ",time_offset=%d", opts->time_offset); 179 return 0; 180 } 181 182 static struct inode *exfat_alloc_inode(struct super_block *sb) 183 { 184 struct exfat_inode_info *ei; 185 186 ei = kmem_cache_alloc(exfat_inode_cachep, GFP_NOFS); 187 if (!ei) 188 return NULL; 189 190 init_rwsem(&ei->truncate_lock); 191 return &ei->vfs_inode; 192 } 193 194 static void exfat_free_inode(struct inode *inode) 195 { 196 kmem_cache_free(exfat_inode_cachep, EXFAT_I(inode)); 197 } 198 199 static const struct super_operations exfat_sops = { 200 .alloc_inode = exfat_alloc_inode, 201 .free_inode = exfat_free_inode, 202 .write_inode = exfat_write_inode, 203 .evict_inode = exfat_evict_inode, 204 .put_super = exfat_put_super, 205 .sync_fs = exfat_sync_fs, 206 .statfs = exfat_statfs, 207 .show_options = exfat_show_options, 208 }; 209 210 enum { 211 Opt_uid, 212 Opt_gid, 213 Opt_umask, 214 Opt_dmask, 215 Opt_fmask, 216 Opt_allow_utime, 217 Opt_charset, 218 Opt_errors, 219 Opt_discard, 220 Opt_time_offset, 221 222 /* Deprecated options */ 223 Opt_utf8, 224 Opt_debug, 225 Opt_namecase, 226 Opt_codepage, 227 }; 228 229 static const struct constant_table exfat_param_enums[] = { 230 { "continue", EXFAT_ERRORS_CONT }, 231 { "panic", EXFAT_ERRORS_PANIC }, 232 { "remount-ro", EXFAT_ERRORS_RO }, 233 {} 234 }; 235 236 static const struct fs_parameter_spec exfat_parameters[] = { 237 fsparam_u32("uid", Opt_uid), 238 fsparam_u32("gid", Opt_gid), 239 fsparam_u32oct("umask", Opt_umask), 240 fsparam_u32oct("dmask", Opt_dmask), 241 fsparam_u32oct("fmask", Opt_fmask), 242 fsparam_u32oct("allow_utime", Opt_allow_utime), 243 fsparam_string("iocharset", Opt_charset), 244 fsparam_enum("errors", Opt_errors, exfat_param_enums), 245 fsparam_flag("discard", Opt_discard), 246 fsparam_s32("time_offset", Opt_time_offset), 247 __fsparam(NULL, "utf8", Opt_utf8, fs_param_deprecated, 248 NULL), 249 __fsparam(NULL, "debug", Opt_debug, fs_param_deprecated, 250 NULL), 251 __fsparam(fs_param_is_u32, "namecase", Opt_namecase, 252 fs_param_deprecated, NULL), 253 __fsparam(fs_param_is_u32, "codepage", Opt_codepage, 254 fs_param_deprecated, NULL), 255 {} 256 }; 257 258 static int exfat_parse_param(struct fs_context *fc, struct fs_parameter *param) 259 { 260 struct exfat_sb_info *sbi = fc->s_fs_info; 261 struct exfat_mount_options *opts = &sbi->options; 262 struct fs_parse_result result; 263 int opt; 264 265 opt = fs_parse(fc, exfat_parameters, param, &result); 266 if (opt < 0) 267 return opt; 268 269 switch (opt) { 270 case Opt_uid: 271 opts->fs_uid = make_kuid(current_user_ns(), result.uint_32); 272 break; 273 case Opt_gid: 274 opts->fs_gid = make_kgid(current_user_ns(), result.uint_32); 275 break; 276 case Opt_umask: 277 opts->fs_fmask = result.uint_32; 278 opts->fs_dmask = result.uint_32; 279 break; 280 case Opt_dmask: 281 opts->fs_dmask = result.uint_32; 282 break; 283 case Opt_fmask: 284 opts->fs_fmask = result.uint_32; 285 break; 286 case Opt_allow_utime: 287 opts->allow_utime = result.uint_32 & 0022; 288 break; 289 case Opt_charset: 290 exfat_free_iocharset(sbi); 291 opts->iocharset = param->string; 292 param->string = NULL; 293 break; 294 case Opt_errors: 295 opts->errors = result.uint_32; 296 break; 297 case Opt_discard: 298 opts->discard = 1; 299 break; 300 case Opt_time_offset: 301 /* 302 * Make the limit 24 just in case someone invents something 303 * unusual. 304 */ 305 if (result.int_32 < -24 * 60 || result.int_32 > 24 * 60) 306 return -EINVAL; 307 opts->time_offset = result.int_32; 308 break; 309 case Opt_utf8: 310 case Opt_debug: 311 case Opt_namecase: 312 case Opt_codepage: 313 break; 314 default: 315 return -EINVAL; 316 } 317 318 return 0; 319 } 320 321 static void exfat_hash_init(struct super_block *sb) 322 { 323 struct exfat_sb_info *sbi = EXFAT_SB(sb); 324 int i; 325 326 spin_lock_init(&sbi->inode_hash_lock); 327 for (i = 0; i < EXFAT_HASH_SIZE; i++) 328 INIT_HLIST_HEAD(&sbi->inode_hashtable[i]); 329 } 330 331 static int exfat_read_root(struct inode *inode) 332 { 333 struct super_block *sb = inode->i_sb; 334 struct exfat_sb_info *sbi = EXFAT_SB(sb); 335 struct exfat_inode_info *ei = EXFAT_I(inode); 336 struct exfat_chain cdir; 337 int num_subdirs, num_clu = 0; 338 339 exfat_chain_set(&ei->dir, sbi->root_dir, 0, ALLOC_FAT_CHAIN); 340 ei->entry = -1; 341 ei->start_clu = sbi->root_dir; 342 ei->flags = ALLOC_FAT_CHAIN; 343 ei->type = TYPE_DIR; 344 ei->version = 0; 345 ei->rwoffset = 0; 346 ei->hint_bmap.off = EXFAT_EOF_CLUSTER; 347 ei->hint_stat.eidx = 0; 348 ei->hint_stat.clu = sbi->root_dir; 349 ei->hint_femp.eidx = EXFAT_HINT_NONE; 350 351 exfat_chain_set(&cdir, sbi->root_dir, 0, ALLOC_FAT_CHAIN); 352 if (exfat_count_num_clusters(sb, &cdir, &num_clu)) 353 return -EIO; 354 i_size_write(inode, num_clu << sbi->cluster_size_bits); 355 356 num_subdirs = exfat_count_dir_entries(sb, &cdir); 357 if (num_subdirs < 0) 358 return -EIO; 359 set_nlink(inode, num_subdirs + EXFAT_MIN_SUBDIR); 360 361 inode->i_uid = sbi->options.fs_uid; 362 inode->i_gid = sbi->options.fs_gid; 363 inode_inc_iversion(inode); 364 inode->i_generation = 0; 365 inode->i_mode = exfat_make_mode(sbi, ATTR_SUBDIR, 0777); 366 inode->i_op = &exfat_dir_inode_operations; 367 inode->i_fop = &exfat_dir_operations; 368 369 inode->i_blocks = ((i_size_read(inode) + (sbi->cluster_size - 1)) 370 & ~(sbi->cluster_size - 1)) >> inode->i_blkbits; 371 EXFAT_I(inode)->i_pos = ((loff_t)sbi->root_dir << 32) | 0xffffffff; 372 EXFAT_I(inode)->i_size_aligned = i_size_read(inode); 373 EXFAT_I(inode)->i_size_ondisk = i_size_read(inode); 374 375 exfat_save_attr(inode, ATTR_SUBDIR); 376 inode->i_mtime = inode->i_atime = inode->i_ctime = ei->i_crtime = 377 current_time(inode); 378 exfat_truncate_atime(&inode->i_atime); 379 exfat_cache_init_inode(inode); 380 return 0; 381 } 382 383 static int exfat_calibrate_blocksize(struct super_block *sb, int logical_sect) 384 { 385 struct exfat_sb_info *sbi = EXFAT_SB(sb); 386 387 if (!is_power_of_2(logical_sect) || 388 logical_sect < 512 || logical_sect > 4096) { 389 exfat_err(sb, "bogus logical sector size %u", logical_sect); 390 return -EIO; 391 } 392 393 if (logical_sect < sb->s_blocksize) { 394 exfat_err(sb, "logical sector size too small for device (logical sector size = %u)", 395 logical_sect); 396 return -EIO; 397 } 398 399 if (logical_sect > sb->s_blocksize) { 400 brelse(sbi->boot_bh); 401 sbi->boot_bh = NULL; 402 403 if (!sb_set_blocksize(sb, logical_sect)) { 404 exfat_err(sb, "unable to set blocksize %u", 405 logical_sect); 406 return -EIO; 407 } 408 sbi->boot_bh = sb_bread(sb, 0); 409 if (!sbi->boot_bh) { 410 exfat_err(sb, "unable to read boot sector (logical sector size = %lu)", 411 sb->s_blocksize); 412 return -EIO; 413 } 414 } 415 return 0; 416 } 417 418 static int exfat_read_boot_sector(struct super_block *sb) 419 { 420 struct boot_sector *p_boot; 421 struct exfat_sb_info *sbi = EXFAT_SB(sb); 422 423 /* set block size to read super block */ 424 sb_min_blocksize(sb, 512); 425 426 /* read boot sector */ 427 sbi->boot_bh = sb_bread(sb, 0); 428 if (!sbi->boot_bh) { 429 exfat_err(sb, "unable to read boot sector"); 430 return -EIO; 431 } 432 p_boot = (struct boot_sector *)sbi->boot_bh->b_data; 433 434 /* check the validity of BOOT */ 435 if (le16_to_cpu((p_boot->signature)) != BOOT_SIGNATURE) { 436 exfat_err(sb, "invalid boot record signature"); 437 return -EINVAL; 438 } 439 440 if (memcmp(p_boot->fs_name, STR_EXFAT, BOOTSEC_FS_NAME_LEN)) { 441 exfat_err(sb, "invalid fs_name"); /* fs_name may unprintable */ 442 return -EINVAL; 443 } 444 445 /* 446 * must_be_zero field must be filled with zero to prevent mounting 447 * from FAT volume. 448 */ 449 if (memchr_inv(p_boot->must_be_zero, 0, sizeof(p_boot->must_be_zero))) 450 return -EINVAL; 451 452 if (p_boot->num_fats != 1 && p_boot->num_fats != 2) { 453 exfat_err(sb, "bogus number of FAT structure"); 454 return -EINVAL; 455 } 456 457 sbi->sect_per_clus = 1 << p_boot->sect_per_clus_bits; 458 sbi->sect_per_clus_bits = p_boot->sect_per_clus_bits; 459 sbi->cluster_size_bits = p_boot->sect_per_clus_bits + 460 p_boot->sect_size_bits; 461 sbi->cluster_size = 1 << sbi->cluster_size_bits; 462 sbi->num_FAT_sectors = le32_to_cpu(p_boot->fat_length); 463 sbi->FAT1_start_sector = le32_to_cpu(p_boot->fat_offset); 464 sbi->FAT2_start_sector = le32_to_cpu(p_boot->fat_offset); 465 if (p_boot->num_fats == 2) 466 sbi->FAT2_start_sector += sbi->num_FAT_sectors; 467 sbi->data_start_sector = le32_to_cpu(p_boot->clu_offset); 468 sbi->num_sectors = le64_to_cpu(p_boot->vol_length); 469 /* because the cluster index starts with 2 */ 470 sbi->num_clusters = le32_to_cpu(p_boot->clu_count) + 471 EXFAT_RESERVED_CLUSTERS; 472 473 sbi->root_dir = le32_to_cpu(p_boot->root_cluster); 474 sbi->dentries_per_clu = 1 << 475 (sbi->cluster_size_bits - DENTRY_SIZE_BITS); 476 477 sbi->vol_flags = le16_to_cpu(p_boot->vol_flags); 478 sbi->vol_flags_persistent = sbi->vol_flags & (VOLUME_DIRTY | MEDIA_FAILURE); 479 sbi->clu_srch_ptr = EXFAT_FIRST_CLUSTER; 480 sbi->used_clusters = EXFAT_CLUSTERS_UNTRACKED; 481 482 /* check consistencies */ 483 if (sbi->num_FAT_sectors << p_boot->sect_size_bits < 484 sbi->num_clusters * 4) { 485 exfat_err(sb, "bogus fat length"); 486 return -EINVAL; 487 } 488 if (sbi->data_start_sector < 489 sbi->FAT1_start_sector + sbi->num_FAT_sectors * p_boot->num_fats) { 490 exfat_err(sb, "bogus data start sector"); 491 return -EINVAL; 492 } 493 if (sbi->vol_flags & VOLUME_DIRTY) 494 exfat_warn(sb, "Volume was not properly unmounted. Some data may be corrupt. Please run fsck."); 495 if (sbi->vol_flags & MEDIA_FAILURE) 496 exfat_warn(sb, "Medium has reported failures. Some data may be lost."); 497 498 /* exFAT file size is limited by a disk volume size */ 499 sb->s_maxbytes = (u64)(sbi->num_clusters - EXFAT_RESERVED_CLUSTERS) << 500 sbi->cluster_size_bits; 501 502 /* check logical sector size */ 503 if (exfat_calibrate_blocksize(sb, 1 << p_boot->sect_size_bits)) 504 return -EIO; 505 506 return 0; 507 } 508 509 static int exfat_verify_boot_region(struct super_block *sb) 510 { 511 struct buffer_head *bh = NULL; 512 u32 chksum = 0; 513 __le32 *p_sig, *p_chksum; 514 int sn, i; 515 516 /* read boot sector sub-regions */ 517 for (sn = 0; sn < 11; sn++) { 518 bh = sb_bread(sb, sn); 519 if (!bh) 520 return -EIO; 521 522 if (sn != 0 && sn <= 8) { 523 /* extended boot sector sub-regions */ 524 p_sig = (__le32 *)&bh->b_data[sb->s_blocksize - 4]; 525 if (le32_to_cpu(*p_sig) != EXBOOT_SIGNATURE) 526 exfat_warn(sb, "Invalid exboot-signature(sector = %d): 0x%08x", 527 sn, le32_to_cpu(*p_sig)); 528 } 529 530 chksum = exfat_calc_chksum32(bh->b_data, sb->s_blocksize, 531 chksum, sn ? CS_DEFAULT : CS_BOOT_SECTOR); 532 brelse(bh); 533 } 534 535 /* boot checksum sub-regions */ 536 bh = sb_bread(sb, sn); 537 if (!bh) 538 return -EIO; 539 540 for (i = 0; i < sb->s_blocksize; i += sizeof(u32)) { 541 p_chksum = (__le32 *)&bh->b_data[i]; 542 if (le32_to_cpu(*p_chksum) != chksum) { 543 exfat_err(sb, "Invalid boot checksum (boot checksum : 0x%08x, checksum : 0x%08x)", 544 le32_to_cpu(*p_chksum), chksum); 545 brelse(bh); 546 return -EINVAL; 547 } 548 } 549 brelse(bh); 550 return 0; 551 } 552 553 /* mount the file system volume */ 554 static int __exfat_fill_super(struct super_block *sb) 555 { 556 int ret; 557 struct exfat_sb_info *sbi = EXFAT_SB(sb); 558 559 ret = exfat_read_boot_sector(sb); 560 if (ret) { 561 exfat_err(sb, "failed to read boot sector"); 562 goto free_bh; 563 } 564 565 ret = exfat_verify_boot_region(sb); 566 if (ret) { 567 exfat_err(sb, "invalid boot region"); 568 goto free_bh; 569 } 570 571 ret = exfat_create_upcase_table(sb); 572 if (ret) { 573 exfat_err(sb, "failed to load upcase table"); 574 goto free_bh; 575 } 576 577 ret = exfat_load_bitmap(sb); 578 if (ret) { 579 exfat_err(sb, "failed to load alloc-bitmap"); 580 goto free_upcase_table; 581 } 582 583 ret = exfat_count_used_clusters(sb, &sbi->used_clusters); 584 if (ret) { 585 exfat_err(sb, "failed to scan clusters"); 586 goto free_alloc_bitmap; 587 } 588 589 return 0; 590 591 free_alloc_bitmap: 592 exfat_free_bitmap(sbi); 593 free_upcase_table: 594 exfat_free_upcase_table(sbi); 595 free_bh: 596 brelse(sbi->boot_bh); 597 return ret; 598 } 599 600 static int exfat_fill_super(struct super_block *sb, struct fs_context *fc) 601 { 602 struct exfat_sb_info *sbi = sb->s_fs_info; 603 struct exfat_mount_options *opts = &sbi->options; 604 struct inode *root_inode; 605 int err; 606 607 if (opts->allow_utime == (unsigned short)-1) 608 opts->allow_utime = ~opts->fs_dmask & 0022; 609 610 if (opts->discard) { 611 struct request_queue *q = bdev_get_queue(sb->s_bdev); 612 613 if (!blk_queue_discard(q)) { 614 exfat_warn(sb, "mounting with \"discard\" option, but the device does not support discard"); 615 opts->discard = 0; 616 } 617 } 618 619 sb->s_flags |= SB_NODIRATIME; 620 sb->s_magic = EXFAT_SUPER_MAGIC; 621 sb->s_op = &exfat_sops; 622 623 sb->s_time_gran = 10 * NSEC_PER_MSEC; 624 sb->s_time_min = EXFAT_MIN_TIMESTAMP_SECS; 625 sb->s_time_max = EXFAT_MAX_TIMESTAMP_SECS; 626 627 err = __exfat_fill_super(sb); 628 if (err) { 629 exfat_err(sb, "failed to recognize exfat type"); 630 goto check_nls_io; 631 } 632 633 /* set up enough so that it can read an inode */ 634 exfat_hash_init(sb); 635 636 if (!strcmp(sbi->options.iocharset, "utf8")) 637 opts->utf8 = 1; 638 else { 639 sbi->nls_io = load_nls(sbi->options.iocharset); 640 if (!sbi->nls_io) { 641 exfat_err(sb, "IO charset %s not found", 642 sbi->options.iocharset); 643 err = -EINVAL; 644 goto free_table; 645 } 646 } 647 648 if (sbi->options.utf8) 649 sb->s_d_op = &exfat_utf8_dentry_ops; 650 else 651 sb->s_d_op = &exfat_dentry_ops; 652 653 root_inode = new_inode(sb); 654 if (!root_inode) { 655 exfat_err(sb, "failed to allocate root inode"); 656 err = -ENOMEM; 657 goto free_table; 658 } 659 660 root_inode->i_ino = EXFAT_ROOT_INO; 661 inode_set_iversion(root_inode, 1); 662 err = exfat_read_root(root_inode); 663 if (err) { 664 exfat_err(sb, "failed to initialize root inode"); 665 goto put_inode; 666 } 667 668 exfat_hash_inode(root_inode, EXFAT_I(root_inode)->i_pos); 669 insert_inode_hash(root_inode); 670 671 sb->s_root = d_make_root(root_inode); 672 if (!sb->s_root) { 673 exfat_err(sb, "failed to get the root dentry"); 674 err = -ENOMEM; 675 goto put_inode; 676 } 677 678 return 0; 679 680 put_inode: 681 iput(root_inode); 682 sb->s_root = NULL; 683 684 free_table: 685 exfat_free_upcase_table(sbi); 686 exfat_free_bitmap(sbi); 687 brelse(sbi->boot_bh); 688 689 check_nls_io: 690 unload_nls(sbi->nls_io); 691 exfat_free_iocharset(sbi); 692 sb->s_fs_info = NULL; 693 kfree(sbi); 694 return err; 695 } 696 697 static int exfat_get_tree(struct fs_context *fc) 698 { 699 return get_tree_bdev(fc, exfat_fill_super); 700 } 701 702 static void exfat_free(struct fs_context *fc) 703 { 704 struct exfat_sb_info *sbi = fc->s_fs_info; 705 706 if (sbi) { 707 exfat_free_iocharset(sbi); 708 kfree(sbi); 709 } 710 } 711 712 static int exfat_reconfigure(struct fs_context *fc) 713 { 714 fc->sb_flags |= SB_NODIRATIME; 715 716 /* volume flag will be updated in exfat_sync_fs */ 717 sync_filesystem(fc->root->d_sb); 718 return 0; 719 } 720 721 static const struct fs_context_operations exfat_context_ops = { 722 .parse_param = exfat_parse_param, 723 .get_tree = exfat_get_tree, 724 .free = exfat_free, 725 .reconfigure = exfat_reconfigure, 726 }; 727 728 static int exfat_init_fs_context(struct fs_context *fc) 729 { 730 struct exfat_sb_info *sbi; 731 732 sbi = kzalloc(sizeof(struct exfat_sb_info), GFP_KERNEL); 733 if (!sbi) 734 return -ENOMEM; 735 736 mutex_init(&sbi->s_lock); 737 ratelimit_state_init(&sbi->ratelimit, DEFAULT_RATELIMIT_INTERVAL, 738 DEFAULT_RATELIMIT_BURST); 739 740 sbi->options.fs_uid = current_uid(); 741 sbi->options.fs_gid = current_gid(); 742 sbi->options.fs_fmask = current->fs->umask; 743 sbi->options.fs_dmask = current->fs->umask; 744 sbi->options.allow_utime = -1; 745 sbi->options.iocharset = exfat_default_iocharset; 746 sbi->options.errors = EXFAT_ERRORS_RO; 747 748 fc->s_fs_info = sbi; 749 fc->ops = &exfat_context_ops; 750 return 0; 751 } 752 753 static struct file_system_type exfat_fs_type = { 754 .owner = THIS_MODULE, 755 .name = "exfat", 756 .init_fs_context = exfat_init_fs_context, 757 .parameters = exfat_parameters, 758 .kill_sb = kill_block_super, 759 .fs_flags = FS_REQUIRES_DEV, 760 }; 761 762 static void exfat_inode_init_once(void *foo) 763 { 764 struct exfat_inode_info *ei = (struct exfat_inode_info *)foo; 765 766 INIT_HLIST_NODE(&ei->i_hash_fat); 767 inode_init_once(&ei->vfs_inode); 768 } 769 770 static int __init init_exfat_fs(void) 771 { 772 int err; 773 774 err = exfat_cache_init(); 775 if (err) 776 return err; 777 778 exfat_inode_cachep = kmem_cache_create("exfat_inode_cache", 779 sizeof(struct exfat_inode_info), 780 0, SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, 781 exfat_inode_init_once); 782 if (!exfat_inode_cachep) { 783 err = -ENOMEM; 784 goto shutdown_cache; 785 } 786 787 err = register_filesystem(&exfat_fs_type); 788 if (err) 789 goto destroy_cache; 790 791 return 0; 792 793 destroy_cache: 794 kmem_cache_destroy(exfat_inode_cachep); 795 shutdown_cache: 796 exfat_cache_shutdown(); 797 return err; 798 } 799 800 static void __exit exit_exfat_fs(void) 801 { 802 /* 803 * Make sure all delayed rcu free inodes are flushed before we 804 * destroy cache. 805 */ 806 rcu_barrier(); 807 kmem_cache_destroy(exfat_inode_cachep); 808 unregister_filesystem(&exfat_fs_type); 809 exfat_cache_shutdown(); 810 } 811 812 module_init(init_exfat_fs); 813 module_exit(exit_exfat_fs); 814 815 MODULE_ALIAS_FS("exfat"); 816 MODULE_LICENSE("GPL"); 817 MODULE_DESCRIPTION("exFAT filesystem support"); 818 MODULE_AUTHOR("Samsung Electronics Co., Ltd."); 819