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