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 return 0; 380 } 381 382 static int exfat_calibrate_blocksize(struct super_block *sb, int logical_sect) 383 { 384 struct exfat_sb_info *sbi = EXFAT_SB(sb); 385 386 if (!is_power_of_2(logical_sect) || 387 logical_sect < 512 || logical_sect > 4096) { 388 exfat_err(sb, "bogus logical sector size %u", logical_sect); 389 return -EIO; 390 } 391 392 if (logical_sect < sb->s_blocksize) { 393 exfat_err(sb, "logical sector size too small for device (logical sector size = %u)", 394 logical_sect); 395 return -EIO; 396 } 397 398 if (logical_sect > sb->s_blocksize) { 399 brelse(sbi->boot_bh); 400 sbi->boot_bh = NULL; 401 402 if (!sb_set_blocksize(sb, logical_sect)) { 403 exfat_err(sb, "unable to set blocksize %u", 404 logical_sect); 405 return -EIO; 406 } 407 sbi->boot_bh = sb_bread(sb, 0); 408 if (!sbi->boot_bh) { 409 exfat_err(sb, "unable to read boot sector (logical sector size = %lu)", 410 sb->s_blocksize); 411 return -EIO; 412 } 413 } 414 return 0; 415 } 416 417 static int exfat_read_boot_sector(struct super_block *sb) 418 { 419 struct boot_sector *p_boot; 420 struct exfat_sb_info *sbi = EXFAT_SB(sb); 421 422 /* set block size to read super block */ 423 sb_min_blocksize(sb, 512); 424 425 /* read boot sector */ 426 sbi->boot_bh = sb_bread(sb, 0); 427 if (!sbi->boot_bh) { 428 exfat_err(sb, "unable to read boot sector"); 429 return -EIO; 430 } 431 p_boot = (struct boot_sector *)sbi->boot_bh->b_data; 432 433 /* check the validity of BOOT */ 434 if (le16_to_cpu((p_boot->signature)) != BOOT_SIGNATURE) { 435 exfat_err(sb, "invalid boot record signature"); 436 return -EINVAL; 437 } 438 439 if (memcmp(p_boot->fs_name, STR_EXFAT, BOOTSEC_FS_NAME_LEN)) { 440 exfat_err(sb, "invalid fs_name"); /* fs_name may unprintable */ 441 return -EINVAL; 442 } 443 444 /* 445 * must_be_zero field must be filled with zero to prevent mounting 446 * from FAT volume. 447 */ 448 if (memchr_inv(p_boot->must_be_zero, 0, sizeof(p_boot->must_be_zero))) 449 return -EINVAL; 450 451 if (p_boot->num_fats != 1 && p_boot->num_fats != 2) { 452 exfat_err(sb, "bogus number of FAT structure"); 453 return -EINVAL; 454 } 455 456 sbi->sect_per_clus = 1 << p_boot->sect_per_clus_bits; 457 sbi->sect_per_clus_bits = p_boot->sect_per_clus_bits; 458 sbi->cluster_size_bits = p_boot->sect_per_clus_bits + 459 p_boot->sect_size_bits; 460 sbi->cluster_size = 1 << sbi->cluster_size_bits; 461 sbi->num_FAT_sectors = le32_to_cpu(p_boot->fat_length); 462 sbi->FAT1_start_sector = le32_to_cpu(p_boot->fat_offset); 463 sbi->FAT2_start_sector = le32_to_cpu(p_boot->fat_offset); 464 if (p_boot->num_fats == 2) 465 sbi->FAT2_start_sector += sbi->num_FAT_sectors; 466 sbi->data_start_sector = le32_to_cpu(p_boot->clu_offset); 467 sbi->num_sectors = le64_to_cpu(p_boot->vol_length); 468 /* because the cluster index starts with 2 */ 469 sbi->num_clusters = le32_to_cpu(p_boot->clu_count) + 470 EXFAT_RESERVED_CLUSTERS; 471 472 sbi->root_dir = le32_to_cpu(p_boot->root_cluster); 473 sbi->dentries_per_clu = 1 << 474 (sbi->cluster_size_bits - DENTRY_SIZE_BITS); 475 476 sbi->vol_flags = le16_to_cpu(p_boot->vol_flags); 477 sbi->vol_flags_persistent = sbi->vol_flags & (VOLUME_DIRTY | MEDIA_FAILURE); 478 sbi->clu_srch_ptr = EXFAT_FIRST_CLUSTER; 479 sbi->used_clusters = EXFAT_CLUSTERS_UNTRACKED; 480 481 /* check consistencies */ 482 if (sbi->num_FAT_sectors << p_boot->sect_size_bits < 483 sbi->num_clusters * 4) { 484 exfat_err(sb, "bogus fat length"); 485 return -EINVAL; 486 } 487 if (sbi->data_start_sector < 488 sbi->FAT1_start_sector + sbi->num_FAT_sectors * p_boot->num_fats) { 489 exfat_err(sb, "bogus data start sector"); 490 return -EINVAL; 491 } 492 if (sbi->vol_flags & VOLUME_DIRTY) 493 exfat_warn(sb, "Volume was not properly unmounted. Some data may be corrupt. Please run fsck."); 494 if (sbi->vol_flags & MEDIA_FAILURE) 495 exfat_warn(sb, "Medium has reported failures. Some data may be lost."); 496 497 /* exFAT file size is limited by a disk volume size */ 498 sb->s_maxbytes = (u64)(sbi->num_clusters - EXFAT_RESERVED_CLUSTERS) << 499 sbi->cluster_size_bits; 500 501 /* check logical sector size */ 502 if (exfat_calibrate_blocksize(sb, 1 << p_boot->sect_size_bits)) 503 return -EIO; 504 505 return 0; 506 } 507 508 static int exfat_verify_boot_region(struct super_block *sb) 509 { 510 struct buffer_head *bh = NULL; 511 u32 chksum = 0; 512 __le32 *p_sig, *p_chksum; 513 int sn, i; 514 515 /* read boot sector sub-regions */ 516 for (sn = 0; sn < 11; sn++) { 517 bh = sb_bread(sb, sn); 518 if (!bh) 519 return -EIO; 520 521 if (sn != 0 && sn <= 8) { 522 /* extended boot sector sub-regions */ 523 p_sig = (__le32 *)&bh->b_data[sb->s_blocksize - 4]; 524 if (le32_to_cpu(*p_sig) != EXBOOT_SIGNATURE) 525 exfat_warn(sb, "Invalid exboot-signature(sector = %d): 0x%08x", 526 sn, le32_to_cpu(*p_sig)); 527 } 528 529 chksum = exfat_calc_chksum32(bh->b_data, sb->s_blocksize, 530 chksum, sn ? CS_DEFAULT : CS_BOOT_SECTOR); 531 brelse(bh); 532 } 533 534 /* boot checksum sub-regions */ 535 bh = sb_bread(sb, sn); 536 if (!bh) 537 return -EIO; 538 539 for (i = 0; i < sb->s_blocksize; i += sizeof(u32)) { 540 p_chksum = (__le32 *)&bh->b_data[i]; 541 if (le32_to_cpu(*p_chksum) != chksum) { 542 exfat_err(sb, "Invalid boot checksum (boot checksum : 0x%08x, checksum : 0x%08x)", 543 le32_to_cpu(*p_chksum), chksum); 544 brelse(bh); 545 return -EINVAL; 546 } 547 } 548 brelse(bh); 549 return 0; 550 } 551 552 /* mount the file system volume */ 553 static int __exfat_fill_super(struct super_block *sb) 554 { 555 int ret; 556 struct exfat_sb_info *sbi = EXFAT_SB(sb); 557 558 ret = exfat_read_boot_sector(sb); 559 if (ret) { 560 exfat_err(sb, "failed to read boot sector"); 561 goto free_bh; 562 } 563 564 ret = exfat_verify_boot_region(sb); 565 if (ret) { 566 exfat_err(sb, "invalid boot region"); 567 goto free_bh; 568 } 569 570 ret = exfat_create_upcase_table(sb); 571 if (ret) { 572 exfat_err(sb, "failed to load upcase table"); 573 goto free_bh; 574 } 575 576 ret = exfat_load_bitmap(sb); 577 if (ret) { 578 exfat_err(sb, "failed to load alloc-bitmap"); 579 goto free_upcase_table; 580 } 581 582 ret = exfat_count_used_clusters(sb, &sbi->used_clusters); 583 if (ret) { 584 exfat_err(sb, "failed to scan clusters"); 585 goto free_alloc_bitmap; 586 } 587 588 return 0; 589 590 free_alloc_bitmap: 591 exfat_free_bitmap(sbi); 592 free_upcase_table: 593 exfat_free_upcase_table(sbi); 594 free_bh: 595 brelse(sbi->boot_bh); 596 return ret; 597 } 598 599 static int exfat_fill_super(struct super_block *sb, struct fs_context *fc) 600 { 601 struct exfat_sb_info *sbi = sb->s_fs_info; 602 struct exfat_mount_options *opts = &sbi->options; 603 struct inode *root_inode; 604 int err; 605 606 if (opts->allow_utime == (unsigned short)-1) 607 opts->allow_utime = ~opts->fs_dmask & 0022; 608 609 if (opts->discard) { 610 struct request_queue *q = bdev_get_queue(sb->s_bdev); 611 612 if (!blk_queue_discard(q)) { 613 exfat_warn(sb, "mounting with \"discard\" option, but the device does not support discard"); 614 opts->discard = 0; 615 } 616 } 617 618 sb->s_flags |= SB_NODIRATIME; 619 sb->s_magic = EXFAT_SUPER_MAGIC; 620 sb->s_op = &exfat_sops; 621 622 sb->s_time_gran = 10 * NSEC_PER_MSEC; 623 sb->s_time_min = EXFAT_MIN_TIMESTAMP_SECS; 624 sb->s_time_max = EXFAT_MAX_TIMESTAMP_SECS; 625 626 err = __exfat_fill_super(sb); 627 if (err) { 628 exfat_err(sb, "failed to recognize exfat type"); 629 goto check_nls_io; 630 } 631 632 /* set up enough so that it can read an inode */ 633 exfat_hash_init(sb); 634 635 if (!strcmp(sbi->options.iocharset, "utf8")) 636 opts->utf8 = 1; 637 else { 638 sbi->nls_io = load_nls(sbi->options.iocharset); 639 if (!sbi->nls_io) { 640 exfat_err(sb, "IO charset %s not found", 641 sbi->options.iocharset); 642 err = -EINVAL; 643 goto free_table; 644 } 645 } 646 647 if (sbi->options.utf8) 648 sb->s_d_op = &exfat_utf8_dentry_ops; 649 else 650 sb->s_d_op = &exfat_dentry_ops; 651 652 root_inode = new_inode(sb); 653 if (!root_inode) { 654 exfat_err(sb, "failed to allocate root inode"); 655 err = -ENOMEM; 656 goto free_table; 657 } 658 659 root_inode->i_ino = EXFAT_ROOT_INO; 660 inode_set_iversion(root_inode, 1); 661 err = exfat_read_root(root_inode); 662 if (err) { 663 exfat_err(sb, "failed to initialize root inode"); 664 goto put_inode; 665 } 666 667 exfat_hash_inode(root_inode, EXFAT_I(root_inode)->i_pos); 668 insert_inode_hash(root_inode); 669 670 sb->s_root = d_make_root(root_inode); 671 if (!sb->s_root) { 672 exfat_err(sb, "failed to get the root dentry"); 673 err = -ENOMEM; 674 goto put_inode; 675 } 676 677 return 0; 678 679 put_inode: 680 iput(root_inode); 681 sb->s_root = NULL; 682 683 free_table: 684 exfat_free_upcase_table(sbi); 685 exfat_free_bitmap(sbi); 686 brelse(sbi->boot_bh); 687 688 check_nls_io: 689 unload_nls(sbi->nls_io); 690 exfat_free_iocharset(sbi); 691 sb->s_fs_info = NULL; 692 kfree(sbi); 693 return err; 694 } 695 696 static int exfat_get_tree(struct fs_context *fc) 697 { 698 return get_tree_bdev(fc, exfat_fill_super); 699 } 700 701 static void exfat_free(struct fs_context *fc) 702 { 703 struct exfat_sb_info *sbi = fc->s_fs_info; 704 705 if (sbi) { 706 exfat_free_iocharset(sbi); 707 kfree(sbi); 708 } 709 } 710 711 static int exfat_reconfigure(struct fs_context *fc) 712 { 713 fc->sb_flags |= SB_NODIRATIME; 714 715 /* volume flag will be updated in exfat_sync_fs */ 716 sync_filesystem(fc->root->d_sb); 717 return 0; 718 } 719 720 static const struct fs_context_operations exfat_context_ops = { 721 .parse_param = exfat_parse_param, 722 .get_tree = exfat_get_tree, 723 .free = exfat_free, 724 .reconfigure = exfat_reconfigure, 725 }; 726 727 static int exfat_init_fs_context(struct fs_context *fc) 728 { 729 struct exfat_sb_info *sbi; 730 731 sbi = kzalloc(sizeof(struct exfat_sb_info), GFP_KERNEL); 732 if (!sbi) 733 return -ENOMEM; 734 735 mutex_init(&sbi->s_lock); 736 ratelimit_state_init(&sbi->ratelimit, DEFAULT_RATELIMIT_INTERVAL, 737 DEFAULT_RATELIMIT_BURST); 738 739 sbi->options.fs_uid = current_uid(); 740 sbi->options.fs_gid = current_gid(); 741 sbi->options.fs_fmask = current->fs->umask; 742 sbi->options.fs_dmask = current->fs->umask; 743 sbi->options.allow_utime = -1; 744 sbi->options.iocharset = exfat_default_iocharset; 745 sbi->options.errors = EXFAT_ERRORS_RO; 746 747 fc->s_fs_info = sbi; 748 fc->ops = &exfat_context_ops; 749 return 0; 750 } 751 752 static struct file_system_type exfat_fs_type = { 753 .owner = THIS_MODULE, 754 .name = "exfat", 755 .init_fs_context = exfat_init_fs_context, 756 .parameters = exfat_parameters, 757 .kill_sb = kill_block_super, 758 .fs_flags = FS_REQUIRES_DEV, 759 }; 760 761 static void exfat_inode_init_once(void *foo) 762 { 763 struct exfat_inode_info *ei = (struct exfat_inode_info *)foo; 764 765 spin_lock_init(&ei->cache_lru_lock); 766 ei->nr_caches = 0; 767 ei->cache_valid_id = EXFAT_CACHE_VALID + 1; 768 INIT_LIST_HEAD(&ei->cache_lru); 769 INIT_HLIST_NODE(&ei->i_hash_fat); 770 inode_init_once(&ei->vfs_inode); 771 } 772 773 static int __init init_exfat_fs(void) 774 { 775 int err; 776 777 err = exfat_cache_init(); 778 if (err) 779 return err; 780 781 exfat_inode_cachep = kmem_cache_create("exfat_inode_cache", 782 sizeof(struct exfat_inode_info), 783 0, SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, 784 exfat_inode_init_once); 785 if (!exfat_inode_cachep) { 786 err = -ENOMEM; 787 goto shutdown_cache; 788 } 789 790 err = register_filesystem(&exfat_fs_type); 791 if (err) 792 goto destroy_cache; 793 794 return 0; 795 796 destroy_cache: 797 kmem_cache_destroy(exfat_inode_cachep); 798 shutdown_cache: 799 exfat_cache_shutdown(); 800 return err; 801 } 802 803 static void __exit exit_exfat_fs(void) 804 { 805 /* 806 * Make sure all delayed rcu free inodes are flushed before we 807 * destroy cache. 808 */ 809 rcu_barrier(); 810 kmem_cache_destroy(exfat_inode_cachep); 811 unregister_filesystem(&exfat_fs_type); 812 exfat_cache_shutdown(); 813 } 814 815 module_init(init_exfat_fs); 816 module_exit(exit_exfat_fs); 817 818 MODULE_ALIAS_FS("exfat"); 819 MODULE_LICENSE("GPL"); 820 MODULE_DESCRIPTION("exFAT filesystem support"); 821 MODULE_AUTHOR("Samsung Electronics Co., Ltd."); 822