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