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_delayed_free(struct rcu_head *p) 35 { 36 struct exfat_sb_info *sbi = container_of(p, struct exfat_sb_info, rcu); 37 38 unload_nls(sbi->nls_io); 39 exfat_free_iocharset(sbi); 40 exfat_free_upcase_table(sbi); 41 kfree(sbi); 42 } 43 44 static void exfat_put_super(struct super_block *sb) 45 { 46 struct exfat_sb_info *sbi = EXFAT_SB(sb); 47 48 mutex_lock(&sbi->s_lock); 49 exfat_free_bitmap(sbi); 50 brelse(sbi->boot_bh); 51 mutex_unlock(&sbi->s_lock); 52 53 call_rcu(&sbi->rcu, exfat_delayed_free); 54 } 55 56 static int exfat_sync_fs(struct super_block *sb, int wait) 57 { 58 struct exfat_sb_info *sbi = EXFAT_SB(sb); 59 int err = 0; 60 61 if (!wait) 62 return 0; 63 64 /* If there are some dirty buffers in the bdev inode */ 65 mutex_lock(&sbi->s_lock); 66 sync_blockdev(sb->s_bdev); 67 if (exfat_clear_volume_dirty(sb)) 68 err = -EIO; 69 mutex_unlock(&sbi->s_lock); 70 return err; 71 } 72 73 static int exfat_statfs(struct dentry *dentry, struct kstatfs *buf) 74 { 75 struct super_block *sb = dentry->d_sb; 76 struct exfat_sb_info *sbi = EXFAT_SB(sb); 77 unsigned long long id = huge_encode_dev(sb->s_bdev->bd_dev); 78 79 if (sbi->used_clusters == EXFAT_CLUSTERS_UNTRACKED) { 80 mutex_lock(&sbi->s_lock); 81 if (exfat_count_used_clusters(sb, &sbi->used_clusters)) { 82 mutex_unlock(&sbi->s_lock); 83 return -EIO; 84 } 85 mutex_unlock(&sbi->s_lock); 86 } 87 88 buf->f_type = sb->s_magic; 89 buf->f_bsize = sbi->cluster_size; 90 buf->f_blocks = sbi->num_clusters - 2; /* clu 0 & 1 */ 91 buf->f_bfree = buf->f_blocks - sbi->used_clusters; 92 buf->f_bavail = buf->f_bfree; 93 buf->f_fsid = u64_to_fsid(id); 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; 103 104 /* 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 set_buffer_uptodate(sbi->boot_bh); 122 mark_buffer_dirty(sbi->boot_bh); 123 124 __sync_dirty_buffer(sbi->boot_bh, REQ_SYNC | REQ_FUA | REQ_PREFLUSH); 125 126 return 0; 127 } 128 129 int exfat_set_volume_dirty(struct super_block *sb) 130 { 131 struct exfat_sb_info *sbi = EXFAT_SB(sb); 132 133 return exfat_set_vol_flags(sb, sbi->vol_flags | VOLUME_DIRTY); 134 } 135 136 int exfat_clear_volume_dirty(struct super_block *sb) 137 { 138 struct exfat_sb_info *sbi = EXFAT_SB(sb); 139 140 return exfat_set_vol_flags(sb, sbi->vol_flags & ~VOLUME_DIRTY); 141 } 142 143 static int exfat_show_options(struct seq_file *m, struct dentry *root) 144 { 145 struct super_block *sb = root->d_sb; 146 struct exfat_sb_info *sbi = EXFAT_SB(sb); 147 struct exfat_mount_options *opts = &sbi->options; 148 149 /* Show partition info */ 150 if (!uid_eq(opts->fs_uid, GLOBAL_ROOT_UID)) 151 seq_printf(m, ",uid=%u", 152 from_kuid_munged(&init_user_ns, opts->fs_uid)); 153 if (!gid_eq(opts->fs_gid, GLOBAL_ROOT_GID)) 154 seq_printf(m, ",gid=%u", 155 from_kgid_munged(&init_user_ns, opts->fs_gid)); 156 seq_printf(m, ",fmask=%04o,dmask=%04o", opts->fs_fmask, opts->fs_dmask); 157 if (opts->allow_utime) 158 seq_printf(m, ",allow_utime=%04o", opts->allow_utime); 159 if (opts->utf8) 160 seq_puts(m, ",iocharset=utf8"); 161 else if (sbi->nls_io) 162 seq_printf(m, ",iocharset=%s", sbi->nls_io->charset); 163 if (opts->errors == EXFAT_ERRORS_CONT) 164 seq_puts(m, ",errors=continue"); 165 else if (opts->errors == EXFAT_ERRORS_PANIC) 166 seq_puts(m, ",errors=panic"); 167 else 168 seq_puts(m, ",errors=remount-ro"); 169 if (opts->discard) 170 seq_puts(m, ",discard"); 171 if (opts->keep_last_dots) 172 seq_puts(m, ",keep_last_dots"); 173 if (opts->time_offset) 174 seq_printf(m, ",time_offset=%d", opts->time_offset); 175 return 0; 176 } 177 178 static struct inode *exfat_alloc_inode(struct super_block *sb) 179 { 180 struct exfat_inode_info *ei; 181 182 ei = alloc_inode_sb(sb, exfat_inode_cachep, GFP_NOFS); 183 if (!ei) 184 return NULL; 185 186 init_rwsem(&ei->truncate_lock); 187 return &ei->vfs_inode; 188 } 189 190 static void exfat_free_inode(struct inode *inode) 191 { 192 kmem_cache_free(exfat_inode_cachep, EXFAT_I(inode)); 193 } 194 195 static const struct super_operations exfat_sops = { 196 .alloc_inode = exfat_alloc_inode, 197 .free_inode = exfat_free_inode, 198 .write_inode = exfat_write_inode, 199 .evict_inode = exfat_evict_inode, 200 .put_super = exfat_put_super, 201 .sync_fs = exfat_sync_fs, 202 .statfs = exfat_statfs, 203 .show_options = exfat_show_options, 204 }; 205 206 enum { 207 Opt_uid, 208 Opt_gid, 209 Opt_umask, 210 Opt_dmask, 211 Opt_fmask, 212 Opt_allow_utime, 213 Opt_charset, 214 Opt_errors, 215 Opt_discard, 216 Opt_keep_last_dots, 217 Opt_time_offset, 218 219 /* Deprecated options */ 220 Opt_utf8, 221 Opt_debug, 222 Opt_namecase, 223 Opt_codepage, 224 }; 225 226 static const struct constant_table exfat_param_enums[] = { 227 { "continue", EXFAT_ERRORS_CONT }, 228 { "panic", EXFAT_ERRORS_PANIC }, 229 { "remount-ro", EXFAT_ERRORS_RO }, 230 {} 231 }; 232 233 static const struct fs_parameter_spec exfat_parameters[] = { 234 fsparam_u32("uid", Opt_uid), 235 fsparam_u32("gid", Opt_gid), 236 fsparam_u32oct("umask", Opt_umask), 237 fsparam_u32oct("dmask", Opt_dmask), 238 fsparam_u32oct("fmask", Opt_fmask), 239 fsparam_u32oct("allow_utime", Opt_allow_utime), 240 fsparam_string("iocharset", Opt_charset), 241 fsparam_enum("errors", Opt_errors, exfat_param_enums), 242 fsparam_flag("discard", Opt_discard), 243 fsparam_flag("keep_last_dots", Opt_keep_last_dots), 244 fsparam_s32("time_offset", Opt_time_offset), 245 __fsparam(NULL, "utf8", Opt_utf8, fs_param_deprecated, 246 NULL), 247 __fsparam(NULL, "debug", Opt_debug, fs_param_deprecated, 248 NULL), 249 __fsparam(fs_param_is_u32, "namecase", Opt_namecase, 250 fs_param_deprecated, NULL), 251 __fsparam(fs_param_is_u32, "codepage", Opt_codepage, 252 fs_param_deprecated, NULL), 253 {} 254 }; 255 256 static int exfat_parse_param(struct fs_context *fc, struct fs_parameter *param) 257 { 258 struct exfat_sb_info *sbi = fc->s_fs_info; 259 struct exfat_mount_options *opts = &sbi->options; 260 struct fs_parse_result result; 261 int opt; 262 263 opt = fs_parse(fc, exfat_parameters, param, &result); 264 if (opt < 0) 265 return opt; 266 267 switch (opt) { 268 case Opt_uid: 269 opts->fs_uid = make_kuid(current_user_ns(), result.uint_32); 270 break; 271 case Opt_gid: 272 opts->fs_gid = make_kgid(current_user_ns(), result.uint_32); 273 break; 274 case Opt_umask: 275 opts->fs_fmask = result.uint_32; 276 opts->fs_dmask = result.uint_32; 277 break; 278 case Opt_dmask: 279 opts->fs_dmask = result.uint_32; 280 break; 281 case Opt_fmask: 282 opts->fs_fmask = result.uint_32; 283 break; 284 case Opt_allow_utime: 285 opts->allow_utime = result.uint_32 & 0022; 286 break; 287 case Opt_charset: 288 exfat_free_iocharset(sbi); 289 opts->iocharset = param->string; 290 param->string = NULL; 291 break; 292 case Opt_errors: 293 opts->errors = result.uint_32; 294 break; 295 case Opt_discard: 296 opts->discard = 1; 297 break; 298 case Opt_keep_last_dots: 299 opts->keep_last_dots = 1; 300 break; 301 case Opt_time_offset: 302 /* 303 * Make the limit 24 just in case someone invents something 304 * unusual. 305 */ 306 if (result.int_32 < -24 * 60 || result.int_32 > 24 * 60) 307 return -EINVAL; 308 opts->time_offset = result.int_32; 309 break; 310 case Opt_utf8: 311 case Opt_debug: 312 case Opt_namecase: 313 case Opt_codepage: 314 break; 315 default: 316 return -EINVAL; 317 } 318 319 return 0; 320 } 321 322 static void exfat_hash_init(struct super_block *sb) 323 { 324 struct exfat_sb_info *sbi = EXFAT_SB(sb); 325 int i; 326 327 spin_lock_init(&sbi->inode_hash_lock); 328 for (i = 0; i < EXFAT_HASH_SIZE; i++) 329 INIT_HLIST_HEAD(&sbi->inode_hashtable[i]); 330 } 331 332 static int exfat_read_root(struct inode *inode) 333 { 334 struct super_block *sb = inode->i_sb; 335 struct exfat_sb_info *sbi = EXFAT_SB(sb); 336 struct exfat_inode_info *ei = EXFAT_I(inode); 337 struct exfat_chain cdir; 338 int num_subdirs, num_clu = 0; 339 340 exfat_chain_set(&ei->dir, sbi->root_dir, 0, ALLOC_FAT_CHAIN); 341 ei->entry = -1; 342 ei->start_clu = sbi->root_dir; 343 ei->flags = ALLOC_FAT_CHAIN; 344 ei->type = TYPE_DIR; 345 ei->version = 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 = round_up(i_size_read(inode), sbi->cluster_size) >> 370 inode->i_blkbits; 371 ei->i_pos = ((loff_t)sbi->root_dir << 32) | 0xffffffff; 372 ei->i_size_aligned = i_size_read(inode); 373 ei->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 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 /* 456 * sect_size_bits could be at least 9 and at most 12. 457 */ 458 if (p_boot->sect_size_bits < EXFAT_MIN_SECT_SIZE_BITS || 459 p_boot->sect_size_bits > EXFAT_MAX_SECT_SIZE_BITS) { 460 exfat_err(sb, "bogus sector size bits : %u\n", 461 p_boot->sect_size_bits); 462 return -EINVAL; 463 } 464 465 /* 466 * sect_per_clus_bits could be at least 0 and at most 25 - sect_size_bits. 467 */ 468 if (p_boot->sect_per_clus_bits > EXFAT_MAX_SECT_PER_CLUS_BITS(p_boot)) { 469 exfat_err(sb, "bogus sectors bits per cluster : %u\n", 470 p_boot->sect_per_clus_bits); 471 return -EINVAL; 472 } 473 474 sbi->sect_per_clus = 1 << p_boot->sect_per_clus_bits; 475 sbi->sect_per_clus_bits = p_boot->sect_per_clus_bits; 476 sbi->cluster_size_bits = p_boot->sect_per_clus_bits + 477 p_boot->sect_size_bits; 478 sbi->cluster_size = 1 << sbi->cluster_size_bits; 479 sbi->num_FAT_sectors = le32_to_cpu(p_boot->fat_length); 480 sbi->FAT1_start_sector = le32_to_cpu(p_boot->fat_offset); 481 sbi->FAT2_start_sector = le32_to_cpu(p_boot->fat_offset); 482 if (p_boot->num_fats == 2) 483 sbi->FAT2_start_sector += sbi->num_FAT_sectors; 484 sbi->data_start_sector = le32_to_cpu(p_boot->clu_offset); 485 sbi->num_sectors = le64_to_cpu(p_boot->vol_length); 486 /* because the cluster index starts with 2 */ 487 sbi->num_clusters = le32_to_cpu(p_boot->clu_count) + 488 EXFAT_RESERVED_CLUSTERS; 489 490 sbi->root_dir = le32_to_cpu(p_boot->root_cluster); 491 sbi->dentries_per_clu = 1 << 492 (sbi->cluster_size_bits - DENTRY_SIZE_BITS); 493 494 sbi->vol_flags = le16_to_cpu(p_boot->vol_flags); 495 sbi->vol_flags_persistent = sbi->vol_flags & (VOLUME_DIRTY | MEDIA_FAILURE); 496 sbi->clu_srch_ptr = EXFAT_FIRST_CLUSTER; 497 sbi->used_clusters = EXFAT_CLUSTERS_UNTRACKED; 498 499 /* check consistencies */ 500 if ((u64)sbi->num_FAT_sectors << p_boot->sect_size_bits < 501 (u64)sbi->num_clusters * 4) { 502 exfat_err(sb, "bogus fat length"); 503 return -EINVAL; 504 } 505 506 if (sbi->data_start_sector < 507 (u64)sbi->FAT1_start_sector + 508 (u64)sbi->num_FAT_sectors * p_boot->num_fats) { 509 exfat_err(sb, "bogus data start sector"); 510 return -EINVAL; 511 } 512 513 if (sbi->vol_flags & VOLUME_DIRTY) 514 exfat_warn(sb, "Volume was not properly unmounted. Some data may be corrupt. Please run fsck."); 515 if (sbi->vol_flags & MEDIA_FAILURE) 516 exfat_warn(sb, "Medium has reported failures. Some data may be lost."); 517 518 /* exFAT file size is limited by a disk volume size */ 519 sb->s_maxbytes = (u64)(sbi->num_clusters - EXFAT_RESERVED_CLUSTERS) << 520 sbi->cluster_size_bits; 521 522 /* check logical sector size */ 523 if (exfat_calibrate_blocksize(sb, 1 << p_boot->sect_size_bits)) 524 return -EIO; 525 526 return 0; 527 } 528 529 static int exfat_verify_boot_region(struct super_block *sb) 530 { 531 struct buffer_head *bh = NULL; 532 u32 chksum = 0; 533 __le32 *p_sig, *p_chksum; 534 int sn, i; 535 536 /* read boot sector sub-regions */ 537 for (sn = 0; sn < 11; sn++) { 538 bh = sb_bread(sb, sn); 539 if (!bh) 540 return -EIO; 541 542 if (sn != 0 && sn <= 8) { 543 /* extended boot sector sub-regions */ 544 p_sig = (__le32 *)&bh->b_data[sb->s_blocksize - 4]; 545 if (le32_to_cpu(*p_sig) != EXBOOT_SIGNATURE) 546 exfat_warn(sb, "Invalid exboot-signature(sector = %d): 0x%08x", 547 sn, le32_to_cpu(*p_sig)); 548 } 549 550 chksum = exfat_calc_chksum32(bh->b_data, sb->s_blocksize, 551 chksum, sn ? CS_DEFAULT : CS_BOOT_SECTOR); 552 brelse(bh); 553 } 554 555 /* boot checksum sub-regions */ 556 bh = sb_bread(sb, sn); 557 if (!bh) 558 return -EIO; 559 560 for (i = 0; i < sb->s_blocksize; i += sizeof(u32)) { 561 p_chksum = (__le32 *)&bh->b_data[i]; 562 if (le32_to_cpu(*p_chksum) != chksum) { 563 exfat_err(sb, "Invalid boot checksum (boot checksum : 0x%08x, checksum : 0x%08x)", 564 le32_to_cpu(*p_chksum), chksum); 565 brelse(bh); 566 return -EINVAL; 567 } 568 } 569 brelse(bh); 570 return 0; 571 } 572 573 /* mount the file system volume */ 574 static int __exfat_fill_super(struct super_block *sb) 575 { 576 int ret; 577 struct exfat_sb_info *sbi = EXFAT_SB(sb); 578 579 ret = exfat_read_boot_sector(sb); 580 if (ret) { 581 exfat_err(sb, "failed to read boot sector"); 582 goto free_bh; 583 } 584 585 ret = exfat_verify_boot_region(sb); 586 if (ret) { 587 exfat_err(sb, "invalid boot region"); 588 goto free_bh; 589 } 590 591 ret = exfat_create_upcase_table(sb); 592 if (ret) { 593 exfat_err(sb, "failed to load upcase table"); 594 goto free_bh; 595 } 596 597 ret = exfat_load_bitmap(sb); 598 if (ret) { 599 exfat_err(sb, "failed to load alloc-bitmap"); 600 goto free_upcase_table; 601 } 602 603 ret = exfat_count_used_clusters(sb, &sbi->used_clusters); 604 if (ret) { 605 exfat_err(sb, "failed to scan clusters"); 606 goto free_alloc_bitmap; 607 } 608 609 return 0; 610 611 free_alloc_bitmap: 612 exfat_free_bitmap(sbi); 613 free_upcase_table: 614 exfat_free_upcase_table(sbi); 615 free_bh: 616 brelse(sbi->boot_bh); 617 return ret; 618 } 619 620 static int exfat_fill_super(struct super_block *sb, struct fs_context *fc) 621 { 622 struct exfat_sb_info *sbi = sb->s_fs_info; 623 struct exfat_mount_options *opts = &sbi->options; 624 struct inode *root_inode; 625 int err; 626 627 if (opts->allow_utime == (unsigned short)-1) 628 opts->allow_utime = ~opts->fs_dmask & 0022; 629 630 if (opts->discard) { 631 struct request_queue *q = bdev_get_queue(sb->s_bdev); 632 633 if (!blk_queue_discard(q)) { 634 exfat_warn(sb, "mounting with \"discard\" option, but the device does not support discard"); 635 opts->discard = 0; 636 } 637 } 638 639 sb->s_flags |= SB_NODIRATIME; 640 sb->s_magic = EXFAT_SUPER_MAGIC; 641 sb->s_op = &exfat_sops; 642 643 sb->s_time_gran = 10 * NSEC_PER_MSEC; 644 sb->s_time_min = EXFAT_MIN_TIMESTAMP_SECS; 645 sb->s_time_max = EXFAT_MAX_TIMESTAMP_SECS; 646 647 err = __exfat_fill_super(sb); 648 if (err) { 649 exfat_err(sb, "failed to recognize exfat type"); 650 goto check_nls_io; 651 } 652 653 /* set up enough so that it can read an inode */ 654 exfat_hash_init(sb); 655 656 if (!strcmp(sbi->options.iocharset, "utf8")) 657 opts->utf8 = 1; 658 else { 659 sbi->nls_io = load_nls(sbi->options.iocharset); 660 if (!sbi->nls_io) { 661 exfat_err(sb, "IO charset %s not found", 662 sbi->options.iocharset); 663 err = -EINVAL; 664 goto free_table; 665 } 666 } 667 668 if (sbi->options.utf8) 669 sb->s_d_op = &exfat_utf8_dentry_ops; 670 else 671 sb->s_d_op = &exfat_dentry_ops; 672 673 root_inode = new_inode(sb); 674 if (!root_inode) { 675 exfat_err(sb, "failed to allocate root inode"); 676 err = -ENOMEM; 677 goto free_table; 678 } 679 680 root_inode->i_ino = EXFAT_ROOT_INO; 681 inode_set_iversion(root_inode, 1); 682 err = exfat_read_root(root_inode); 683 if (err) { 684 exfat_err(sb, "failed to initialize root inode"); 685 goto put_inode; 686 } 687 688 exfat_hash_inode(root_inode, EXFAT_I(root_inode)->i_pos); 689 insert_inode_hash(root_inode); 690 691 sb->s_root = d_make_root(root_inode); 692 if (!sb->s_root) { 693 exfat_err(sb, "failed to get the root dentry"); 694 err = -ENOMEM; 695 goto free_table; 696 } 697 698 return 0; 699 700 put_inode: 701 iput(root_inode); 702 sb->s_root = NULL; 703 704 free_table: 705 exfat_free_upcase_table(sbi); 706 exfat_free_bitmap(sbi); 707 brelse(sbi->boot_bh); 708 709 check_nls_io: 710 unload_nls(sbi->nls_io); 711 exfat_free_iocharset(sbi); 712 sb->s_fs_info = NULL; 713 kfree(sbi); 714 return err; 715 } 716 717 static int exfat_get_tree(struct fs_context *fc) 718 { 719 return get_tree_bdev(fc, exfat_fill_super); 720 } 721 722 static void exfat_free(struct fs_context *fc) 723 { 724 struct exfat_sb_info *sbi = fc->s_fs_info; 725 726 if (sbi) { 727 exfat_free_iocharset(sbi); 728 kfree(sbi); 729 } 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 struct file_system_type exfat_fs_type = { 775 .owner = THIS_MODULE, 776 .name = "exfat", 777 .init_fs_context = exfat_init_fs_context, 778 .parameters = exfat_parameters, 779 .kill_sb = kill_block_super, 780 .fs_flags = FS_REQUIRES_DEV, 781 }; 782 783 static void exfat_inode_init_once(void *foo) 784 { 785 struct exfat_inode_info *ei = (struct exfat_inode_info *)foo; 786 787 spin_lock_init(&ei->cache_lru_lock); 788 ei->nr_caches = 0; 789 ei->cache_valid_id = EXFAT_CACHE_VALID + 1; 790 INIT_LIST_HEAD(&ei->cache_lru); 791 INIT_HLIST_NODE(&ei->i_hash_fat); 792 inode_init_once(&ei->vfs_inode); 793 } 794 795 static int __init init_exfat_fs(void) 796 { 797 int err; 798 799 err = exfat_cache_init(); 800 if (err) 801 return err; 802 803 exfat_inode_cachep = kmem_cache_create("exfat_inode_cache", 804 sizeof(struct exfat_inode_info), 805 0, SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, 806 exfat_inode_init_once); 807 if (!exfat_inode_cachep) { 808 err = -ENOMEM; 809 goto shutdown_cache; 810 } 811 812 err = register_filesystem(&exfat_fs_type); 813 if (err) 814 goto destroy_cache; 815 816 return 0; 817 818 destroy_cache: 819 kmem_cache_destroy(exfat_inode_cachep); 820 shutdown_cache: 821 exfat_cache_shutdown(); 822 return err; 823 } 824 825 static void __exit exit_exfat_fs(void) 826 { 827 /* 828 * Make sure all delayed rcu free inodes are flushed before we 829 * destroy cache. 830 */ 831 rcu_barrier(); 832 kmem_cache_destroy(exfat_inode_cachep); 833 unregister_filesystem(&exfat_fs_type); 834 exfat_cache_shutdown(); 835 } 836 837 module_init(init_exfat_fs); 838 module_exit(exit_exfat_fs); 839 840 MODULE_ALIAS_FS("exfat"); 841 MODULE_LICENSE("GPL"); 842 MODULE_DESCRIPTION("exFAT filesystem support"); 843 MODULE_AUTHOR("Samsung Electronics Co., Ltd."); 844