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_put_super(struct super_block *sb) 35 { 36 struct exfat_sb_info *sbi = EXFAT_SB(sb); 37 38 mutex_lock(&sbi->s_lock); 39 exfat_free_bitmap(sbi); 40 brelse(sbi->boot_bh); 41 mutex_unlock(&sbi->s_lock); 42 } 43 44 static int exfat_sync_fs(struct super_block *sb, int wait) 45 { 46 struct exfat_sb_info *sbi = EXFAT_SB(sb); 47 int err = 0; 48 49 if (!wait) 50 return 0; 51 52 /* If there are some dirty buffers in the bdev inode */ 53 mutex_lock(&sbi->s_lock); 54 sync_blockdev(sb->s_bdev); 55 if (exfat_clear_volume_dirty(sb)) 56 err = -EIO; 57 mutex_unlock(&sbi->s_lock); 58 return err; 59 } 60 61 static int exfat_statfs(struct dentry *dentry, struct kstatfs *buf) 62 { 63 struct super_block *sb = dentry->d_sb; 64 struct exfat_sb_info *sbi = EXFAT_SB(sb); 65 unsigned long long id = huge_encode_dev(sb->s_bdev->bd_dev); 66 67 if (sbi->used_clusters == EXFAT_CLUSTERS_UNTRACKED) { 68 mutex_lock(&sbi->s_lock); 69 if (exfat_count_used_clusters(sb, &sbi->used_clusters)) { 70 mutex_unlock(&sbi->s_lock); 71 return -EIO; 72 } 73 mutex_unlock(&sbi->s_lock); 74 } 75 76 buf->f_type = sb->s_magic; 77 buf->f_bsize = sbi->cluster_size; 78 buf->f_blocks = sbi->num_clusters - 2; /* clu 0 & 1 */ 79 buf->f_bfree = buf->f_blocks - sbi->used_clusters; 80 buf->f_bavail = buf->f_bfree; 81 buf->f_fsid = u64_to_fsid(id); 82 /* Unicode utf16 255 characters */ 83 buf->f_namelen = EXFAT_MAX_FILE_LEN * NLS_MAX_CHARSET_SIZE; 84 return 0; 85 } 86 87 static int exfat_set_vol_flags(struct super_block *sb, unsigned short new_flags) 88 { 89 struct exfat_sb_info *sbi = EXFAT_SB(sb); 90 struct boot_sector *p_boot = (struct boot_sector *)sbi->boot_bh->b_data; 91 92 /* retain persistent-flags */ 93 new_flags |= sbi->vol_flags_persistent; 94 95 /* flags are not changed */ 96 if (sbi->vol_flags == new_flags) 97 return 0; 98 99 sbi->vol_flags = new_flags; 100 101 /* skip updating volume dirty flag, 102 * if this volume has been mounted with read-only 103 */ 104 if (sb_rdonly(sb)) 105 return 0; 106 107 p_boot->vol_flags = cpu_to_le16(new_flags); 108 109 set_buffer_uptodate(sbi->boot_bh); 110 mark_buffer_dirty(sbi->boot_bh); 111 112 __sync_dirty_buffer(sbi->boot_bh, REQ_SYNC | REQ_FUA | REQ_PREFLUSH); 113 114 return 0; 115 } 116 117 int exfat_set_volume_dirty(struct super_block *sb) 118 { 119 struct exfat_sb_info *sbi = EXFAT_SB(sb); 120 121 return exfat_set_vol_flags(sb, sbi->vol_flags | VOLUME_DIRTY); 122 } 123 124 int exfat_clear_volume_dirty(struct super_block *sb) 125 { 126 struct exfat_sb_info *sbi = EXFAT_SB(sb); 127 128 return exfat_set_vol_flags(sb, sbi->vol_flags & ~VOLUME_DIRTY); 129 } 130 131 static int exfat_show_options(struct seq_file *m, struct dentry *root) 132 { 133 struct super_block *sb = root->d_sb; 134 struct exfat_sb_info *sbi = EXFAT_SB(sb); 135 struct exfat_mount_options *opts = &sbi->options; 136 137 /* Show partition info */ 138 if (!uid_eq(opts->fs_uid, GLOBAL_ROOT_UID)) 139 seq_printf(m, ",uid=%u", 140 from_kuid_munged(&init_user_ns, opts->fs_uid)); 141 if (!gid_eq(opts->fs_gid, GLOBAL_ROOT_GID)) 142 seq_printf(m, ",gid=%u", 143 from_kgid_munged(&init_user_ns, opts->fs_gid)); 144 seq_printf(m, ",fmask=%04o,dmask=%04o", opts->fs_fmask, opts->fs_dmask); 145 if (opts->allow_utime) 146 seq_printf(m, ",allow_utime=%04o", opts->allow_utime); 147 if (opts->utf8) 148 seq_puts(m, ",iocharset=utf8"); 149 else if (sbi->nls_io) 150 seq_printf(m, ",iocharset=%s", sbi->nls_io->charset); 151 if (opts->errors == EXFAT_ERRORS_CONT) 152 seq_puts(m, ",errors=continue"); 153 else if (opts->errors == EXFAT_ERRORS_PANIC) 154 seq_puts(m, ",errors=panic"); 155 else 156 seq_puts(m, ",errors=remount-ro"); 157 if (opts->discard) 158 seq_puts(m, ",discard"); 159 if (opts->keep_last_dots) 160 seq_puts(m, ",keep_last_dots"); 161 if (opts->sys_tz) 162 seq_puts(m, ",sys_tz"); 163 else if (opts->time_offset) 164 seq_printf(m, ",time_offset=%d", opts->time_offset); 165 if (opts->zero_size_dir) 166 seq_puts(m, ",zero_size_dir"); 167 return 0; 168 } 169 170 static struct inode *exfat_alloc_inode(struct super_block *sb) 171 { 172 struct exfat_inode_info *ei; 173 174 ei = alloc_inode_sb(sb, exfat_inode_cachep, GFP_NOFS); 175 if (!ei) 176 return NULL; 177 178 init_rwsem(&ei->truncate_lock); 179 return &ei->vfs_inode; 180 } 181 182 static void exfat_free_inode(struct inode *inode) 183 { 184 kmem_cache_free(exfat_inode_cachep, EXFAT_I(inode)); 185 } 186 187 static const struct super_operations exfat_sops = { 188 .alloc_inode = exfat_alloc_inode, 189 .free_inode = exfat_free_inode, 190 .write_inode = exfat_write_inode, 191 .evict_inode = exfat_evict_inode, 192 .put_super = exfat_put_super, 193 .sync_fs = exfat_sync_fs, 194 .statfs = exfat_statfs, 195 .show_options = exfat_show_options, 196 }; 197 198 enum { 199 Opt_uid, 200 Opt_gid, 201 Opt_umask, 202 Opt_dmask, 203 Opt_fmask, 204 Opt_allow_utime, 205 Opt_charset, 206 Opt_errors, 207 Opt_discard, 208 Opt_keep_last_dots, 209 Opt_sys_tz, 210 Opt_time_offset, 211 Opt_zero_size_dir, 212 213 /* Deprecated options */ 214 Opt_utf8, 215 Opt_debug, 216 Opt_namecase, 217 Opt_codepage, 218 }; 219 220 static const struct constant_table exfat_param_enums[] = { 221 { "continue", EXFAT_ERRORS_CONT }, 222 { "panic", EXFAT_ERRORS_PANIC }, 223 { "remount-ro", EXFAT_ERRORS_RO }, 224 {} 225 }; 226 227 static const struct fs_parameter_spec exfat_parameters[] = { 228 fsparam_u32("uid", Opt_uid), 229 fsparam_u32("gid", Opt_gid), 230 fsparam_u32oct("umask", Opt_umask), 231 fsparam_u32oct("dmask", Opt_dmask), 232 fsparam_u32oct("fmask", Opt_fmask), 233 fsparam_u32oct("allow_utime", Opt_allow_utime), 234 fsparam_string("iocharset", Opt_charset), 235 fsparam_enum("errors", Opt_errors, exfat_param_enums), 236 fsparam_flag("discard", Opt_discard), 237 fsparam_flag("keep_last_dots", Opt_keep_last_dots), 238 fsparam_flag("sys_tz", Opt_sys_tz), 239 fsparam_s32("time_offset", Opt_time_offset), 240 fsparam_flag("zero_size_dir", Opt_zero_size_dir), 241 __fsparam(NULL, "utf8", Opt_utf8, fs_param_deprecated, 242 NULL), 243 __fsparam(NULL, "debug", Opt_debug, fs_param_deprecated, 244 NULL), 245 __fsparam(fs_param_is_u32, "namecase", Opt_namecase, 246 fs_param_deprecated, NULL), 247 __fsparam(fs_param_is_u32, "codepage", Opt_codepage, 248 fs_param_deprecated, NULL), 249 {} 250 }; 251 252 static int exfat_parse_param(struct fs_context *fc, struct fs_parameter *param) 253 { 254 struct exfat_sb_info *sbi = fc->s_fs_info; 255 struct exfat_mount_options *opts = &sbi->options; 256 struct fs_parse_result result; 257 int opt; 258 259 opt = fs_parse(fc, exfat_parameters, param, &result); 260 if (opt < 0) 261 return opt; 262 263 switch (opt) { 264 case Opt_uid: 265 opts->fs_uid = make_kuid(current_user_ns(), result.uint_32); 266 break; 267 case Opt_gid: 268 opts->fs_gid = make_kgid(current_user_ns(), result.uint_32); 269 break; 270 case Opt_umask: 271 opts->fs_fmask = result.uint_32; 272 opts->fs_dmask = result.uint_32; 273 break; 274 case Opt_dmask: 275 opts->fs_dmask = result.uint_32; 276 break; 277 case Opt_fmask: 278 opts->fs_fmask = result.uint_32; 279 break; 280 case Opt_allow_utime: 281 opts->allow_utime = result.uint_32 & 0022; 282 break; 283 case Opt_charset: 284 exfat_free_iocharset(sbi); 285 opts->iocharset = param->string; 286 param->string = NULL; 287 break; 288 case Opt_errors: 289 opts->errors = result.uint_32; 290 break; 291 case Opt_discard: 292 opts->discard = 1; 293 break; 294 case Opt_keep_last_dots: 295 opts->keep_last_dots = 1; 296 break; 297 case Opt_sys_tz: 298 opts->sys_tz = 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_zero_size_dir: 310 opts->zero_size_dir = true; 311 break; 312 case Opt_utf8: 313 case Opt_debug: 314 case Opt_namecase: 315 case Opt_codepage: 316 break; 317 default: 318 return -EINVAL; 319 } 320 321 return 0; 322 } 323 324 static void exfat_hash_init(struct super_block *sb) 325 { 326 struct exfat_sb_info *sbi = EXFAT_SB(sb); 327 int i; 328 329 spin_lock_init(&sbi->inode_hash_lock); 330 for (i = 0; i < EXFAT_HASH_SIZE; i++) 331 INIT_HLIST_HEAD(&sbi->inode_hashtable[i]); 332 } 333 334 static int exfat_read_root(struct inode *inode) 335 { 336 struct super_block *sb = inode->i_sb; 337 struct exfat_sb_info *sbi = EXFAT_SB(sb); 338 struct exfat_inode_info *ei = EXFAT_I(inode); 339 struct exfat_chain cdir; 340 int num_subdirs, num_clu = 0; 341 342 exfat_chain_set(&ei->dir, sbi->root_dir, 0, ALLOC_FAT_CHAIN); 343 ei->entry = -1; 344 ei->start_clu = sbi->root_dir; 345 ei->flags = ALLOC_FAT_CHAIN; 346 ei->type = TYPE_DIR; 347 ei->version = 0; 348 ei->hint_bmap.off = EXFAT_EOF_CLUSTER; 349 ei->hint_stat.eidx = 0; 350 ei->hint_stat.clu = sbi->root_dir; 351 ei->hint_femp.eidx = EXFAT_HINT_NONE; 352 353 exfat_chain_set(&cdir, sbi->root_dir, 0, ALLOC_FAT_CHAIN); 354 if (exfat_count_num_clusters(sb, &cdir, &num_clu)) 355 return -EIO; 356 i_size_write(inode, num_clu << sbi->cluster_size_bits); 357 358 num_subdirs = exfat_count_dir_entries(sb, &cdir); 359 if (num_subdirs < 0) 360 return -EIO; 361 set_nlink(inode, num_subdirs + EXFAT_MIN_SUBDIR); 362 363 inode->i_uid = sbi->options.fs_uid; 364 inode->i_gid = sbi->options.fs_gid; 365 inode_inc_iversion(inode); 366 inode->i_generation = 0; 367 inode->i_mode = exfat_make_mode(sbi, EXFAT_ATTR_SUBDIR, 0777); 368 inode->i_op = &exfat_dir_inode_operations; 369 inode->i_fop = &exfat_dir_operations; 370 371 inode->i_blocks = round_up(i_size_read(inode), sbi->cluster_size) >> 9; 372 ei->i_pos = ((loff_t)sbi->root_dir << 32) | 0xffffffff; 373 ei->i_size_aligned = i_size_read(inode); 374 ei->i_size_ondisk = i_size_read(inode); 375 376 exfat_save_attr(inode, EXFAT_ATTR_SUBDIR); 377 ei->i_crtime = simple_inode_init_ts(inode); 378 exfat_truncate_inode_atime(inode); 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", 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", 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_bh; 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_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 && !bdev_max_discard_sectors(sb->s_bdev)) { 629 exfat_warn(sb, "mounting with \"discard\" option, but the device does not support discard"); 630 opts->discard = 0; 631 } 632 633 sb->s_flags |= SB_NODIRATIME; 634 sb->s_magic = EXFAT_SUPER_MAGIC; 635 sb->s_op = &exfat_sops; 636 637 sb->s_time_gran = 10 * NSEC_PER_MSEC; 638 sb->s_time_min = EXFAT_MIN_TIMESTAMP_SECS; 639 sb->s_time_max = EXFAT_MAX_TIMESTAMP_SECS; 640 641 err = __exfat_fill_super(sb); 642 if (err) { 643 exfat_err(sb, "failed to recognize exfat type"); 644 goto check_nls_io; 645 } 646 647 /* set up enough so that it can read an inode */ 648 exfat_hash_init(sb); 649 650 if (!strcmp(sbi->options.iocharset, "utf8")) 651 opts->utf8 = 1; 652 else { 653 sbi->nls_io = load_nls(sbi->options.iocharset); 654 if (!sbi->nls_io) { 655 exfat_err(sb, "IO charset %s not found", 656 sbi->options.iocharset); 657 err = -EINVAL; 658 goto free_table; 659 } 660 } 661 662 if (sbi->options.utf8) 663 sb->s_d_op = &exfat_utf8_dentry_ops; 664 else 665 sb->s_d_op = &exfat_dentry_ops; 666 667 root_inode = new_inode(sb); 668 if (!root_inode) { 669 exfat_err(sb, "failed to allocate root inode"); 670 err = -ENOMEM; 671 goto free_table; 672 } 673 674 root_inode->i_ino = EXFAT_ROOT_INO; 675 inode_set_iversion(root_inode, 1); 676 err = exfat_read_root(root_inode); 677 if (err) { 678 exfat_err(sb, "failed to initialize root inode"); 679 goto put_inode; 680 } 681 682 exfat_hash_inode(root_inode, EXFAT_I(root_inode)->i_pos); 683 insert_inode_hash(root_inode); 684 685 sb->s_root = d_make_root(root_inode); 686 if (!sb->s_root) { 687 exfat_err(sb, "failed to get the root dentry"); 688 err = -ENOMEM; 689 goto free_table; 690 } 691 692 return 0; 693 694 put_inode: 695 iput(root_inode); 696 sb->s_root = NULL; 697 698 free_table: 699 exfat_free_bitmap(sbi); 700 brelse(sbi->boot_bh); 701 702 check_nls_io: 703 return err; 704 } 705 706 static int exfat_get_tree(struct fs_context *fc) 707 { 708 return get_tree_bdev(fc, exfat_fill_super); 709 } 710 711 static void exfat_free_sbi(struct exfat_sb_info *sbi) 712 { 713 exfat_free_iocharset(sbi); 714 kfree(sbi); 715 } 716 717 static void exfat_free(struct fs_context *fc) 718 { 719 struct exfat_sb_info *sbi = fc->s_fs_info; 720 721 if (sbi) 722 exfat_free_sbi(sbi); 723 } 724 725 static int exfat_reconfigure(struct fs_context *fc) 726 { 727 fc->sb_flags |= SB_NODIRATIME; 728 729 /* volume flag will be updated in exfat_sync_fs */ 730 sync_filesystem(fc->root->d_sb); 731 return 0; 732 } 733 734 static const struct fs_context_operations exfat_context_ops = { 735 .parse_param = exfat_parse_param, 736 .get_tree = exfat_get_tree, 737 .free = exfat_free, 738 .reconfigure = exfat_reconfigure, 739 }; 740 741 static int exfat_init_fs_context(struct fs_context *fc) 742 { 743 struct exfat_sb_info *sbi; 744 745 sbi = kzalloc(sizeof(struct exfat_sb_info), GFP_KERNEL); 746 if (!sbi) 747 return -ENOMEM; 748 749 mutex_init(&sbi->s_lock); 750 mutex_init(&sbi->bitmap_lock); 751 ratelimit_state_init(&sbi->ratelimit, DEFAULT_RATELIMIT_INTERVAL, 752 DEFAULT_RATELIMIT_BURST); 753 754 sbi->options.fs_uid = current_uid(); 755 sbi->options.fs_gid = current_gid(); 756 sbi->options.fs_fmask = current->fs->umask; 757 sbi->options.fs_dmask = current->fs->umask; 758 sbi->options.allow_utime = -1; 759 sbi->options.iocharset = exfat_default_iocharset; 760 sbi->options.errors = EXFAT_ERRORS_RO; 761 762 fc->s_fs_info = sbi; 763 fc->ops = &exfat_context_ops; 764 return 0; 765 } 766 767 static void delayed_free(struct rcu_head *p) 768 { 769 struct exfat_sb_info *sbi = container_of(p, struct exfat_sb_info, rcu); 770 771 unload_nls(sbi->nls_io); 772 exfat_free_upcase_table(sbi); 773 exfat_free_sbi(sbi); 774 } 775 776 static void exfat_kill_sb(struct super_block *sb) 777 { 778 struct exfat_sb_info *sbi = sb->s_fs_info; 779 780 kill_block_super(sb); 781 if (sbi) 782 call_rcu(&sbi->rcu, delayed_free); 783 } 784 785 static struct file_system_type exfat_fs_type = { 786 .owner = THIS_MODULE, 787 .name = "exfat", 788 .init_fs_context = exfat_init_fs_context, 789 .parameters = exfat_parameters, 790 .kill_sb = exfat_kill_sb, 791 .fs_flags = FS_REQUIRES_DEV, 792 }; 793 794 static void exfat_inode_init_once(void *foo) 795 { 796 struct exfat_inode_info *ei = (struct exfat_inode_info *)foo; 797 798 spin_lock_init(&ei->cache_lru_lock); 799 ei->nr_caches = 0; 800 ei->cache_valid_id = EXFAT_CACHE_VALID + 1; 801 INIT_LIST_HEAD(&ei->cache_lru); 802 INIT_HLIST_NODE(&ei->i_hash_fat); 803 inode_init_once(&ei->vfs_inode); 804 } 805 806 static int __init init_exfat_fs(void) 807 { 808 int err; 809 810 err = exfat_cache_init(); 811 if (err) 812 return err; 813 814 exfat_inode_cachep = kmem_cache_create("exfat_inode_cache", 815 sizeof(struct exfat_inode_info), 816 0, SLAB_RECLAIM_ACCOUNT, 817 exfat_inode_init_once); 818 if (!exfat_inode_cachep) { 819 err = -ENOMEM; 820 goto shutdown_cache; 821 } 822 823 err = register_filesystem(&exfat_fs_type); 824 if (err) 825 goto destroy_cache; 826 827 return 0; 828 829 destroy_cache: 830 kmem_cache_destroy(exfat_inode_cachep); 831 shutdown_cache: 832 exfat_cache_shutdown(); 833 return err; 834 } 835 836 static void __exit exit_exfat_fs(void) 837 { 838 /* 839 * Make sure all delayed rcu free inodes are flushed before we 840 * destroy cache. 841 */ 842 rcu_barrier(); 843 kmem_cache_destroy(exfat_inode_cachep); 844 unregister_filesystem(&exfat_fs_type); 845 exfat_cache_shutdown(); 846 } 847 848 module_init(init_exfat_fs); 849 module_exit(exit_exfat_fs); 850 851 MODULE_ALIAS_FS("exfat"); 852 MODULE_LICENSE("GPL"); 853 MODULE_DESCRIPTION("exFAT filesystem support"); 854 MODULE_AUTHOR("Samsung Electronics Co., Ltd."); 855