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->hint_bmap.off = EXFAT_EOF_CLUSTER; 346 ei->hint_stat.eidx = 0; 347 ei->hint_stat.clu = sbi->root_dir; 348 ei->hint_femp.eidx = EXFAT_HINT_NONE; 349 350 exfat_chain_set(&cdir, sbi->root_dir, 0, ALLOC_FAT_CHAIN); 351 if (exfat_count_num_clusters(sb, &cdir, &num_clu)) 352 return -EIO; 353 i_size_write(inode, num_clu << sbi->cluster_size_bits); 354 355 num_subdirs = exfat_count_dir_entries(sb, &cdir); 356 if (num_subdirs < 0) 357 return -EIO; 358 set_nlink(inode, num_subdirs + EXFAT_MIN_SUBDIR); 359 360 inode->i_uid = sbi->options.fs_uid; 361 inode->i_gid = sbi->options.fs_gid; 362 inode_inc_iversion(inode); 363 inode->i_generation = 0; 364 inode->i_mode = exfat_make_mode(sbi, ATTR_SUBDIR, 0777); 365 inode->i_op = &exfat_dir_inode_operations; 366 inode->i_fop = &exfat_dir_operations; 367 368 inode->i_blocks = ((i_size_read(inode) + (sbi->cluster_size - 1)) 369 & ~(sbi->cluster_size - 1)) >> inode->i_blkbits; 370 EXFAT_I(inode)->i_pos = ((loff_t)sbi->root_dir << 32) | 0xffffffff; 371 EXFAT_I(inode)->i_size_aligned = i_size_read(inode); 372 EXFAT_I(inode)->i_size_ondisk = i_size_read(inode); 373 374 exfat_save_attr(inode, ATTR_SUBDIR); 375 inode->i_mtime = inode->i_atime = inode->i_ctime = ei->i_crtime = 376 current_time(inode); 377 exfat_truncate_atime(&inode->i_atime); 378 return 0; 379 } 380 381 static int exfat_calibrate_blocksize(struct super_block *sb, int logical_sect) 382 { 383 struct exfat_sb_info *sbi = EXFAT_SB(sb); 384 385 if (!is_power_of_2(logical_sect) || 386 logical_sect < 512 || logical_sect > 4096) { 387 exfat_err(sb, "bogus logical sector size %u", logical_sect); 388 return -EIO; 389 } 390 391 if (logical_sect < sb->s_blocksize) { 392 exfat_err(sb, "logical sector size too small for device (logical sector size = %u)", 393 logical_sect); 394 return -EIO; 395 } 396 397 if (logical_sect > sb->s_blocksize) { 398 brelse(sbi->boot_bh); 399 sbi->boot_bh = NULL; 400 401 if (!sb_set_blocksize(sb, logical_sect)) { 402 exfat_err(sb, "unable to set blocksize %u", 403 logical_sect); 404 return -EIO; 405 } 406 sbi->boot_bh = sb_bread(sb, 0); 407 if (!sbi->boot_bh) { 408 exfat_err(sb, "unable to read boot sector (logical sector size = %lu)", 409 sb->s_blocksize); 410 return -EIO; 411 } 412 } 413 return 0; 414 } 415 416 static int exfat_read_boot_sector(struct super_block *sb) 417 { 418 struct boot_sector *p_boot; 419 struct exfat_sb_info *sbi = EXFAT_SB(sb); 420 421 /* set block size to read super block */ 422 sb_min_blocksize(sb, 512); 423 424 /* read boot sector */ 425 sbi->boot_bh = sb_bread(sb, 0); 426 if (!sbi->boot_bh) { 427 exfat_err(sb, "unable to read boot sector"); 428 return -EIO; 429 } 430 p_boot = (struct boot_sector *)sbi->boot_bh->b_data; 431 432 /* check the validity of BOOT */ 433 if (le16_to_cpu((p_boot->signature)) != BOOT_SIGNATURE) { 434 exfat_err(sb, "invalid boot record signature"); 435 return -EINVAL; 436 } 437 438 if (memcmp(p_boot->fs_name, STR_EXFAT, BOOTSEC_FS_NAME_LEN)) { 439 exfat_err(sb, "invalid fs_name"); /* fs_name may unprintable */ 440 return -EINVAL; 441 } 442 443 /* 444 * must_be_zero field must be filled with zero to prevent mounting 445 * from FAT volume. 446 */ 447 if (memchr_inv(p_boot->must_be_zero, 0, sizeof(p_boot->must_be_zero))) 448 return -EINVAL; 449 450 if (p_boot->num_fats != 1 && p_boot->num_fats != 2) { 451 exfat_err(sb, "bogus number of FAT structure"); 452 return -EINVAL; 453 } 454 455 sbi->sect_per_clus = 1 << p_boot->sect_per_clus_bits; 456 sbi->sect_per_clus_bits = p_boot->sect_per_clus_bits; 457 sbi->cluster_size_bits = p_boot->sect_per_clus_bits + 458 p_boot->sect_size_bits; 459 sbi->cluster_size = 1 << sbi->cluster_size_bits; 460 sbi->num_FAT_sectors = le32_to_cpu(p_boot->fat_length); 461 sbi->FAT1_start_sector = le32_to_cpu(p_boot->fat_offset); 462 sbi->FAT2_start_sector = le32_to_cpu(p_boot->fat_offset); 463 if (p_boot->num_fats == 2) 464 sbi->FAT2_start_sector += sbi->num_FAT_sectors; 465 sbi->data_start_sector = le32_to_cpu(p_boot->clu_offset); 466 sbi->num_sectors = le64_to_cpu(p_boot->vol_length); 467 /* because the cluster index starts with 2 */ 468 sbi->num_clusters = le32_to_cpu(p_boot->clu_count) + 469 EXFAT_RESERVED_CLUSTERS; 470 471 sbi->root_dir = le32_to_cpu(p_boot->root_cluster); 472 sbi->dentries_per_clu = 1 << 473 (sbi->cluster_size_bits - DENTRY_SIZE_BITS); 474 475 sbi->vol_flags = le16_to_cpu(p_boot->vol_flags); 476 sbi->vol_flags_persistent = sbi->vol_flags & (VOLUME_DIRTY | MEDIA_FAILURE); 477 sbi->clu_srch_ptr = EXFAT_FIRST_CLUSTER; 478 sbi->used_clusters = EXFAT_CLUSTERS_UNTRACKED; 479 480 /* check consistencies */ 481 if (sbi->num_FAT_sectors << p_boot->sect_size_bits < 482 sbi->num_clusters * 4) { 483 exfat_err(sb, "bogus fat length"); 484 return -EINVAL; 485 } 486 if (sbi->data_start_sector < 487 sbi->FAT1_start_sector + sbi->num_FAT_sectors * p_boot->num_fats) { 488 exfat_err(sb, "bogus data start sector"); 489 return -EINVAL; 490 } 491 if (sbi->vol_flags & VOLUME_DIRTY) 492 exfat_warn(sb, "Volume was not properly unmounted. Some data may be corrupt. Please run fsck."); 493 if (sbi->vol_flags & MEDIA_FAILURE) 494 exfat_warn(sb, "Medium has reported failures. Some data may be lost."); 495 496 /* exFAT file size is limited by a disk volume size */ 497 sb->s_maxbytes = (u64)(sbi->num_clusters - EXFAT_RESERVED_CLUSTERS) << 498 sbi->cluster_size_bits; 499 500 /* check logical sector size */ 501 if (exfat_calibrate_blocksize(sb, 1 << p_boot->sect_size_bits)) 502 return -EIO; 503 504 return 0; 505 } 506 507 static int exfat_verify_boot_region(struct super_block *sb) 508 { 509 struct buffer_head *bh = NULL; 510 u32 chksum = 0; 511 __le32 *p_sig, *p_chksum; 512 int sn, i; 513 514 /* read boot sector sub-regions */ 515 for (sn = 0; sn < 11; sn++) { 516 bh = sb_bread(sb, sn); 517 if (!bh) 518 return -EIO; 519 520 if (sn != 0 && sn <= 8) { 521 /* extended boot sector sub-regions */ 522 p_sig = (__le32 *)&bh->b_data[sb->s_blocksize - 4]; 523 if (le32_to_cpu(*p_sig) != EXBOOT_SIGNATURE) 524 exfat_warn(sb, "Invalid exboot-signature(sector = %d): 0x%08x", 525 sn, le32_to_cpu(*p_sig)); 526 } 527 528 chksum = exfat_calc_chksum32(bh->b_data, sb->s_blocksize, 529 chksum, sn ? CS_DEFAULT : CS_BOOT_SECTOR); 530 brelse(bh); 531 } 532 533 /* boot checksum sub-regions */ 534 bh = sb_bread(sb, sn); 535 if (!bh) 536 return -EIO; 537 538 for (i = 0; i < sb->s_blocksize; i += sizeof(u32)) { 539 p_chksum = (__le32 *)&bh->b_data[i]; 540 if (le32_to_cpu(*p_chksum) != chksum) { 541 exfat_err(sb, "Invalid boot checksum (boot checksum : 0x%08x, checksum : 0x%08x)", 542 le32_to_cpu(*p_chksum), chksum); 543 brelse(bh); 544 return -EINVAL; 545 } 546 } 547 brelse(bh); 548 return 0; 549 } 550 551 /* mount the file system volume */ 552 static int __exfat_fill_super(struct super_block *sb) 553 { 554 int ret; 555 struct exfat_sb_info *sbi = EXFAT_SB(sb); 556 557 ret = exfat_read_boot_sector(sb); 558 if (ret) { 559 exfat_err(sb, "failed to read boot sector"); 560 goto free_bh; 561 } 562 563 ret = exfat_verify_boot_region(sb); 564 if (ret) { 565 exfat_err(sb, "invalid boot region"); 566 goto free_bh; 567 } 568 569 ret = exfat_create_upcase_table(sb); 570 if (ret) { 571 exfat_err(sb, "failed to load upcase table"); 572 goto free_bh; 573 } 574 575 ret = exfat_load_bitmap(sb); 576 if (ret) { 577 exfat_err(sb, "failed to load alloc-bitmap"); 578 goto free_upcase_table; 579 } 580 581 ret = exfat_count_used_clusters(sb, &sbi->used_clusters); 582 if (ret) { 583 exfat_err(sb, "failed to scan clusters"); 584 goto free_alloc_bitmap; 585 } 586 587 return 0; 588 589 free_alloc_bitmap: 590 exfat_free_bitmap(sbi); 591 free_upcase_table: 592 exfat_free_upcase_table(sbi); 593 free_bh: 594 brelse(sbi->boot_bh); 595 return ret; 596 } 597 598 static int exfat_fill_super(struct super_block *sb, struct fs_context *fc) 599 { 600 struct exfat_sb_info *sbi = sb->s_fs_info; 601 struct exfat_mount_options *opts = &sbi->options; 602 struct inode *root_inode; 603 int err; 604 605 if (opts->allow_utime == (unsigned short)-1) 606 opts->allow_utime = ~opts->fs_dmask & 0022; 607 608 if (opts->discard) { 609 struct request_queue *q = bdev_get_queue(sb->s_bdev); 610 611 if (!blk_queue_discard(q)) { 612 exfat_warn(sb, "mounting with \"discard\" option, but the device does not support discard"); 613 opts->discard = 0; 614 } 615 } 616 617 sb->s_flags |= SB_NODIRATIME; 618 sb->s_magic = EXFAT_SUPER_MAGIC; 619 sb->s_op = &exfat_sops; 620 621 sb->s_time_gran = 10 * NSEC_PER_MSEC; 622 sb->s_time_min = EXFAT_MIN_TIMESTAMP_SECS; 623 sb->s_time_max = EXFAT_MAX_TIMESTAMP_SECS; 624 625 err = __exfat_fill_super(sb); 626 if (err) { 627 exfat_err(sb, "failed to recognize exfat type"); 628 goto check_nls_io; 629 } 630 631 /* set up enough so that it can read an inode */ 632 exfat_hash_init(sb); 633 634 if (!strcmp(sbi->options.iocharset, "utf8")) 635 opts->utf8 = 1; 636 else { 637 sbi->nls_io = load_nls(sbi->options.iocharset); 638 if (!sbi->nls_io) { 639 exfat_err(sb, "IO charset %s not found", 640 sbi->options.iocharset); 641 err = -EINVAL; 642 goto free_table; 643 } 644 } 645 646 if (sbi->options.utf8) 647 sb->s_d_op = &exfat_utf8_dentry_ops; 648 else 649 sb->s_d_op = &exfat_dentry_ops; 650 651 root_inode = new_inode(sb); 652 if (!root_inode) { 653 exfat_err(sb, "failed to allocate root inode"); 654 err = -ENOMEM; 655 goto free_table; 656 } 657 658 root_inode->i_ino = EXFAT_ROOT_INO; 659 inode_set_iversion(root_inode, 1); 660 err = exfat_read_root(root_inode); 661 if (err) { 662 exfat_err(sb, "failed to initialize root inode"); 663 goto put_inode; 664 } 665 666 exfat_hash_inode(root_inode, EXFAT_I(root_inode)->i_pos); 667 insert_inode_hash(root_inode); 668 669 sb->s_root = d_make_root(root_inode); 670 if (!sb->s_root) { 671 exfat_err(sb, "failed to get the root dentry"); 672 err = -ENOMEM; 673 goto put_inode; 674 } 675 676 return 0; 677 678 put_inode: 679 iput(root_inode); 680 sb->s_root = NULL; 681 682 free_table: 683 exfat_free_upcase_table(sbi); 684 exfat_free_bitmap(sbi); 685 brelse(sbi->boot_bh); 686 687 check_nls_io: 688 unload_nls(sbi->nls_io); 689 exfat_free_iocharset(sbi); 690 sb->s_fs_info = NULL; 691 kfree(sbi); 692 return err; 693 } 694 695 static int exfat_get_tree(struct fs_context *fc) 696 { 697 return get_tree_bdev(fc, exfat_fill_super); 698 } 699 700 static void exfat_free(struct fs_context *fc) 701 { 702 struct exfat_sb_info *sbi = fc->s_fs_info; 703 704 if (sbi) { 705 exfat_free_iocharset(sbi); 706 kfree(sbi); 707 } 708 } 709 710 static int exfat_reconfigure(struct fs_context *fc) 711 { 712 fc->sb_flags |= SB_NODIRATIME; 713 714 /* volume flag will be updated in exfat_sync_fs */ 715 sync_filesystem(fc->root->d_sb); 716 return 0; 717 } 718 719 static const struct fs_context_operations exfat_context_ops = { 720 .parse_param = exfat_parse_param, 721 .get_tree = exfat_get_tree, 722 .free = exfat_free, 723 .reconfigure = exfat_reconfigure, 724 }; 725 726 static int exfat_init_fs_context(struct fs_context *fc) 727 { 728 struct exfat_sb_info *sbi; 729 730 sbi = kzalloc(sizeof(struct exfat_sb_info), GFP_KERNEL); 731 if (!sbi) 732 return -ENOMEM; 733 734 mutex_init(&sbi->s_lock); 735 ratelimit_state_init(&sbi->ratelimit, DEFAULT_RATELIMIT_INTERVAL, 736 DEFAULT_RATELIMIT_BURST); 737 738 sbi->options.fs_uid = current_uid(); 739 sbi->options.fs_gid = current_gid(); 740 sbi->options.fs_fmask = current->fs->umask; 741 sbi->options.fs_dmask = current->fs->umask; 742 sbi->options.allow_utime = -1; 743 sbi->options.iocharset = exfat_default_iocharset; 744 sbi->options.errors = EXFAT_ERRORS_RO; 745 746 fc->s_fs_info = sbi; 747 fc->ops = &exfat_context_ops; 748 return 0; 749 } 750 751 static struct file_system_type exfat_fs_type = { 752 .owner = THIS_MODULE, 753 .name = "exfat", 754 .init_fs_context = exfat_init_fs_context, 755 .parameters = exfat_parameters, 756 .kill_sb = kill_block_super, 757 .fs_flags = FS_REQUIRES_DEV, 758 }; 759 760 static void exfat_inode_init_once(void *foo) 761 { 762 struct exfat_inode_info *ei = (struct exfat_inode_info *)foo; 763 764 spin_lock_init(&ei->cache_lru_lock); 765 ei->nr_caches = 0; 766 ei->cache_valid_id = EXFAT_CACHE_VALID + 1; 767 INIT_LIST_HEAD(&ei->cache_lru); 768 INIT_HLIST_NODE(&ei->i_hash_fat); 769 inode_init_once(&ei->vfs_inode); 770 } 771 772 static int __init init_exfat_fs(void) 773 { 774 int err; 775 776 err = exfat_cache_init(); 777 if (err) 778 return err; 779 780 exfat_inode_cachep = kmem_cache_create("exfat_inode_cache", 781 sizeof(struct exfat_inode_info), 782 0, SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, 783 exfat_inode_init_once); 784 if (!exfat_inode_cachep) { 785 err = -ENOMEM; 786 goto shutdown_cache; 787 } 788 789 err = register_filesystem(&exfat_fs_type); 790 if (err) 791 goto destroy_cache; 792 793 return 0; 794 795 destroy_cache: 796 kmem_cache_destroy(exfat_inode_cachep); 797 shutdown_cache: 798 exfat_cache_shutdown(); 799 return err; 800 } 801 802 static void __exit exit_exfat_fs(void) 803 { 804 /* 805 * Make sure all delayed rcu free inodes are flushed before we 806 * destroy cache. 807 */ 808 rcu_barrier(); 809 kmem_cache_destroy(exfat_inode_cachep); 810 unregister_filesystem(&exfat_fs_type); 811 exfat_cache_shutdown(); 812 } 813 814 module_init(init_exfat_fs); 815 module_exit(exit_exfat_fs); 816 817 MODULE_ALIAS_FS("exfat"); 818 MODULE_LICENSE("GPL"); 819 MODULE_DESCRIPTION("exFAT filesystem support"); 820 MODULE_AUTHOR("Samsung Electronics Co., Ltd."); 821