fs/exfat/namei.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
   4  */
   5
   6 #include <linux/iversion.h>
   7 #include <linux/namei.h>
   8 #include <linux/slab.h>
   9 #include <linux/buffer_head.h>
  10 #include <linux/nls.h>
  11
  12 #include "exfat_raw.h"
  13 #include "exfat_fs.h"
  14
  15 static inline unsigned long exfat_d_version(struct dentry *dentry)
  16 {
  17         return (unsigned long) dentry->d_fsdata;
  18 }
  19
  20 static inline void exfat_d_version_set(struct dentry *dentry,
  21                 unsigned long version)
  22 {
  23         dentry->d_fsdata = (void *) version;
  24 }
  25
  26 /*
  27  * If new entry was created in the parent, it could create the 8.3 alias (the
  28  * shortname of logname).  So, the parent may have the negative-dentry which
  29  * matches the created 8.3 alias.
  30  *
  31  * If it happened, the negative dentry isn't actually negative anymore.  So,
  32  * drop it.
  33  */
  34 static int exfat_d_revalidate(struct dentry *dentry, unsigned int flags)
  35 {
  36         int ret;
  37
  38         if (flags & LOOKUP_RCU)
  39                 return -ECHILD;
  40
  41         /*
  42          * This is not negative dentry. Always valid.
  43          *
  44          * Note, rename() to existing directory entry will have ->d_inode, and
  45          * will use existing name which isn't specified name by user.
  46          *
  47          * We may be able to drop this positive dentry here. But dropping
  48          * positive dentry isn't good idea. So it's unsupported like
  49          * rename("filename", "FILENAME") for now.
  50          */
  51         if (d_really_is_positive(dentry))
  52                 return 1;
  53
  54         /*
  55          * Drop the negative dentry, in order to make sure to use the case
  56          * sensitive name which is specified by user if this is for creation.
  57          */
  58         if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))
  59                 return 0;
  60
  61         spin_lock(&dentry->d_lock);
  62         ret = inode_eq_iversion(d_inode(dentry->d_parent),
  63                         exfat_d_version(dentry));
  64         spin_unlock(&dentry->d_lock);
  65         return ret;
  66 }
  67
  68 /* returns the length of a struct qstr, ignoring trailing dots if necessary */
  69 static unsigned int exfat_striptail_len(unsigned int len, const char *name,
  70                                         bool keep_last_dots)
  71 {
  72         if (!keep_last_dots) {
  73                 while (len && name[len - 1] == '.')
  74                         len--;
  75         }
  76         return len;
  77 }
  78
  79 /*
  80  * Compute the hash for the exfat name corresponding to the dentry.  If the name
  81  * is invalid, we leave the hash code unchanged so that the existing dentry can
  82  * be used. The exfat fs routines will return ENOENT or EINVAL as appropriate.
  83  */
  84 static int exfat_d_hash(const struct dentry *dentry, struct qstr *qstr)
  85 {
  86         struct super_block *sb = dentry->d_sb;
  87         struct nls_table *t = EXFAT_SB(sb)->nls_io;
  88         const unsigned char *name = qstr->name;
  89         unsigned int len = exfat_striptail_len(qstr->len, qstr->name,
  90                            EXFAT_SB(sb)->options.keep_last_dots);
  91         unsigned long hash = init_name_hash(dentry);
  92         int i, charlen;
  93         wchar_t c;
  94
  95         for (i = 0; i < len; i += charlen) {
  96                 charlen = t->char2uni(&name[i], len - i, &c);
  97                 if (charlen < 0)
  98                         return charlen;
  99                 hash = partial_name_hash(exfat_toupper(sb, c), hash);
 100         }
 101
 102         qstr->hash = end_name_hash(hash);
 103         return 0;
 104 }
 105
 106 static int exfat_d_cmp(const struct dentry *dentry, unsigned int len,
 107                 const char *str, const struct qstr *name)
 108 {
 109         struct super_block *sb = dentry->d_sb;
 110         struct nls_table *t = EXFAT_SB(sb)->nls_io;
 111         unsigned int alen = exfat_striptail_len(name->len, name->name,
 112                                 EXFAT_SB(sb)->options.keep_last_dots);
 113         unsigned int blen = exfat_striptail_len(len, str,
 114                                 EXFAT_SB(sb)->options.keep_last_dots);
 115         wchar_t c1, c2;
 116         int charlen, i;
 117
 118         if (alen != blen)
 119                 return 1;
 120
 121         for (i = 0; i < len; i += charlen) {
 122                 charlen = t->char2uni(&name->name[i], alen - i, &c1);
 123                 if (charlen < 0)
 124                         return 1;
 125                 if (charlen != t->char2uni(&str[i], blen - i, &c2))
 126                         return 1;
 127
 128                 if (exfat_toupper(sb, c1) != exfat_toupper(sb, c2))
 129                         return 1;
 130         }
 131
 132         return 0;
 133 }
 134
 135 const struct dentry_operations exfat_dentry_ops = {
 136         .d_revalidate   = exfat_d_revalidate,
 137         .d_hash         = exfat_d_hash,
 138         .d_compare      = exfat_d_cmp,
 139 };
 140
 141 static int exfat_utf8_d_hash(const struct dentry *dentry, struct qstr *qstr)
 142 {
 143         struct super_block *sb = dentry->d_sb;
 144         const unsigned char *name = qstr->name;
 145         unsigned int len = exfat_striptail_len(qstr->len, qstr->name,
 146                                EXFAT_SB(sb)->options.keep_last_dots);
 147         unsigned long hash = init_name_hash(dentry);
 148         int i, charlen;
 149         unicode_t u;
 150
 151         for (i = 0; i < len; i += charlen) {
 152                 charlen = utf8_to_utf32(&name[i], len - i, &u);
 153                 if (charlen < 0)
 154                         return charlen;
 155
 156                 /*
 157                  * exfat_toupper() works only for code points up to the U+FFFF.
 158                  */
 159                 hash = partial_name_hash(u <= 0xFFFF ? exfat_toupper(sb, u) : u,
 160                                          hash);
 161         }
 162
 163         qstr->hash = end_name_hash(hash);
 164         return 0;
 165 }
 166
 167 static int exfat_utf8_d_cmp(const struct dentry *dentry, unsigned int len,
 168                 const char *str, const struct qstr *name)
 169 {
 170         struct super_block *sb = dentry->d_sb;
 171         unsigned int alen = exfat_striptail_len(name->len, name->name,
 172                                 EXFAT_SB(sb)->options.keep_last_dots);
 173         unsigned int blen = exfat_striptail_len(len, str,
 174                                 EXFAT_SB(sb)->options.keep_last_dots);
 175
 176         unicode_t u_a, u_b;
 177         int charlen, i;
 178
 179         if (alen != blen)
 180                 return 1;
 181
 182         for (i = 0; i < alen; i += charlen) {
 183                 charlen = utf8_to_utf32(&name->name[i], alen - i, &u_a);
 184                 if (charlen < 0)
 185                         return 1;
 186                 if (charlen != utf8_to_utf32(&str[i], blen - i, &u_b))
 187                         return 1;
 188
 189                 if (u_a <= 0xFFFF && u_b <= 0xFFFF) {
 190                         if (exfat_toupper(sb, u_a) != exfat_toupper(sb, u_b))
 191                                 return 1;
 192                 } else {
 193                         if (u_a != u_b)
 194                                 return 1;
 195                 }
 196         }
 197
 198         return 0;
 199 }
 200
 201 const struct dentry_operations exfat_utf8_dentry_ops = {
 202         .d_revalidate   = exfat_d_revalidate,
 203         .d_hash         = exfat_utf8_d_hash,
 204         .d_compare      = exfat_utf8_d_cmp,
 205 };
 206
 207 /* used only in search empty_slot() */
 208 #define CNT_UNUSED_NOHIT        (-1)
 209 #define CNT_UNUSED_HIT          (-2)
 210 /* search EMPTY CONTINUOUS "num_entries" entries */
 211 static int exfat_search_empty_slot(struct super_block *sb,
 212                 struct exfat_hint_femp *hint_femp, struct exfat_chain *p_dir,
 213                 int num_entries)
 214 {
 215         int i, dentry, num_empty = 0;
 216         int dentries_per_clu;
 217         unsigned int type;
 218         struct exfat_chain clu;
 219         struct exfat_dentry *ep;
 220         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 221         struct buffer_head *bh;
 222
 223         dentries_per_clu = sbi->dentries_per_clu;
 224
 225         if (hint_femp->eidx != EXFAT_HINT_NONE) {
 226                 dentry = hint_femp->eidx;
 227                 if (num_entries <= hint_femp->count) {
 228                         hint_femp->eidx = EXFAT_HINT_NONE;
 229                         return dentry;
 230                 }
 231
 232                 exfat_chain_dup(&clu, &hint_femp->cur);
 233         } else {
 234                 exfat_chain_dup(&clu, p_dir);
 235                 dentry = 0;
 236         }
 237
 238         while (clu.dir != EXFAT_EOF_CLUSTER) {
 239                 i = dentry & (dentries_per_clu - 1);
 240
 241                 for (; i < dentries_per_clu; i++, dentry++) {
 242                         ep = exfat_get_dentry(sb, &clu, i, &bh);
 243                         if (!ep)
 244                                 return -EIO;
 245                         type = exfat_get_entry_type(ep);
 246                         brelse(bh);
 247
 248                         if (type == TYPE_UNUSED || type == TYPE_DELETED) {
 249                                 num_empty++;
 250                                 if (hint_femp->eidx == EXFAT_HINT_NONE) {
 251                                         hint_femp->eidx = dentry;
 252                                         hint_femp->count = CNT_UNUSED_NOHIT;
 253                                         exfat_chain_set(&hint_femp->cur,
 254                                                 clu.dir, clu.size, clu.flags);
 255                                 }
 256
 257                                 if (type == TYPE_UNUSED &&
 258                                     hint_femp->count != CNT_UNUSED_HIT)
 259                                         hint_femp->count = CNT_UNUSED_HIT;
 260                         } else {
 261                                 if (hint_femp->eidx != EXFAT_HINT_NONE &&
 262                                     hint_femp->count == CNT_UNUSED_HIT) {
 263                                         /* unused empty group means
 264                                          * an empty group which includes
 265                                          * unused dentry
 266                                          */
 267                                         exfat_fs_error(sb,
 268                                                 "found bogus dentry(%d) beyond unused empty group(%d) (start_clu : %u, cur_clu : %u)",
 269                                                 dentry, hint_femp->eidx,
 270                                                 p_dir->dir, clu.dir);
 271                                         return -EIO;
 272                                 }
 273
 274                                 num_empty = 0;
 275                                 hint_femp->eidx = EXFAT_HINT_NONE;
 276                         }
 277
 278                         if (num_empty >= num_entries) {
 279                                 /* found and invalidate hint_femp */
 280                                 hint_femp->eidx = EXFAT_HINT_NONE;
 281                                 return (dentry - (num_entries - 1));
 282                         }
 283                 }
 284
 285                 if (clu.flags == ALLOC_NO_FAT_CHAIN) {
 286                         if (--clu.size > 0)
 287                                 clu.dir++;
 288                         else
 289                                 clu.dir = EXFAT_EOF_CLUSTER;
 290                 } else {
 291                         if (exfat_get_next_cluster(sb, &clu.dir))
 292                                 return -EIO;
 293                 }
 294         }
 295
 296         return -ENOSPC;
 297 }
 298
 299 static int exfat_check_max_dentries(struct inode *inode)
 300 {
 301         if (EXFAT_B_TO_DEN(i_size_read(inode)) >= MAX_EXFAT_DENTRIES) {
 302                 /*
 303                  * exFAT spec allows a dir to grow up to 8388608(256MB)
 304                  * dentries
 305                  */
 306                 return -ENOSPC;
 307         }
 308         return 0;
 309 }
 310
 311 /* find empty directory entry.
 312  * if there isn't any empty slot, expand cluster chain.
 313  */
 314 static int exfat_find_empty_entry(struct inode *inode,
 315                 struct exfat_chain *p_dir, int num_entries)
 316 {
 317         int dentry;
 318         unsigned int ret, last_clu;
 319         loff_t size = 0;
 320         struct exfat_chain clu;
 321         struct super_block *sb = inode->i_sb;
 322         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 323         struct exfat_inode_info *ei = EXFAT_I(inode);
 324         struct exfat_hint_femp hint_femp;
 325
 326         hint_femp.eidx = EXFAT_HINT_NONE;
 327
 328         if (ei->hint_femp.eidx != EXFAT_HINT_NONE) {
 329                 hint_femp = ei->hint_femp;
 330                 ei->hint_femp.eidx = EXFAT_HINT_NONE;
 331         }
 332
 333         while ((dentry = exfat_search_empty_slot(sb, &hint_femp, p_dir,
 334                                         num_entries)) < 0) {
 335                 if (dentry == -EIO)
 336                         break;
 337
 338                 if (exfat_check_max_dentries(inode))
 339                         return -ENOSPC;
 340
 341                 /* we trust p_dir->size regardless of FAT type */
 342                 if (exfat_find_last_cluster(sb, p_dir, &last_clu))
 343                         return -EIO;
 344
 345                 /*
 346                  * Allocate new cluster to this directory
 347                  */
 348                 exfat_chain_set(&clu, last_clu + 1, 0, p_dir->flags);
 349
 350                 /* allocate a cluster */
 351                 ret = exfat_alloc_cluster(inode, 1, &clu, IS_DIRSYNC(inode));
 352                 if (ret)
 353                         return ret;
 354
 355                 if (exfat_zeroed_cluster(inode, clu.dir))
 356                         return -EIO;
 357
 358                 /* append to the FAT chain */
 359                 if (clu.flags != p_dir->flags) {
 360                         /* no-fat-chain bit is disabled,
 361                          * so fat-chain should be synced with alloc-bitmap
 362                          */
 363                         exfat_chain_cont_cluster(sb, p_dir->dir, p_dir->size);
 364                         p_dir->flags = ALLOC_FAT_CHAIN;
 365                         hint_femp.cur.flags = ALLOC_FAT_CHAIN;
 366                 }
 367
 368                 if (clu.flags == ALLOC_FAT_CHAIN)
 369                         if (exfat_ent_set(sb, last_clu, clu.dir))
 370                                 return -EIO;
 371
 372                 if (hint_femp.eidx == EXFAT_HINT_NONE) {
 373                         /* the special case that new dentry
 374                          * should be allocated from the start of new cluster
 375                          */
 376                         hint_femp.eidx = EXFAT_B_TO_DEN_IDX(p_dir->size, sbi);
 377                         hint_femp.count = sbi->dentries_per_clu;
 378
 379                         exfat_chain_set(&hint_femp.cur, clu.dir, 0, clu.flags);
 380                 }
 381                 hint_femp.cur.size++;
 382                 p_dir->size++;
 383                 size = EXFAT_CLU_TO_B(p_dir->size, sbi);
 384
 385                 /* directory inode should be updated in here */
 386                 i_size_write(inode, size);
 387                 ei->i_size_ondisk += sbi->cluster_size;
 388                 ei->i_size_aligned += sbi->cluster_size;
 389                 ei->flags = p_dir->flags;
 390                 inode->i_blocks += 1 << sbi->sect_per_clus_bits;
 391         }
 392
 393         return dentry;
 394 }
 395
 396 /*
 397  * Name Resolution Functions :
 398  * Zero if it was successful; otherwise nonzero.
 399  */
 400 static int __exfat_resolve_path(struct inode *inode, const unsigned char *path,
 401                 struct exfat_chain *p_dir, struct exfat_uni_name *p_uniname,
 402                 int lookup)
 403 {
 404         int namelen;
 405         int lossy = NLS_NAME_NO_LOSSY;
 406         struct super_block *sb = inode->i_sb;
 407         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 408         struct exfat_inode_info *ei = EXFAT_I(inode);
 409         int pathlen = strlen(path);
 410
 411         /*
 412          * get the length of the pathname excluding
 413          * trailing periods, if any.
 414          */
 415         namelen = exfat_striptail_len(pathlen, path, false);
 416         if (EXFAT_SB(sb)->options.keep_last_dots) {
 417                 /*
 418                  * Do not allow the creation of files with names
 419                  * ending with period(s).
 420                  */
 421                 if (!lookup && (namelen < pathlen))
 422                         return -EINVAL;
 423                 namelen = pathlen;
 424         }
 425         if (!namelen)
 426                 return -ENOENT;
 427         if (pathlen > (MAX_NAME_LENGTH * MAX_CHARSET_SIZE))
 428                 return -ENAMETOOLONG;
 429
 430         /*
 431          * strip all leading spaces :
 432          * "MS windows 7" supports leading spaces.
 433          * So we should skip this preprocessing for compatibility.
 434          */
 435
 436         /* file name conversion :
 437          * If lookup case, we allow bad-name for compatibility.
 438          */
 439         namelen = exfat_nls_to_utf16(sb, path, namelen, p_uniname,
 440                         &lossy);
 441         if (namelen < 0)
 442                 return namelen; /* return error value */
 443
 444         if ((lossy && !lookup) || !namelen)
 445                 return (lossy & NLS_NAME_OVERLEN) ? -ENAMETOOLONG : -EINVAL;
 446
 447         exfat_chain_set(p_dir, ei->start_clu,
 448                 EXFAT_B_TO_CLU(i_size_read(inode), sbi), ei->flags);
 449
 450         return 0;
 451 }
 452
 453 static inline int exfat_resolve_path(struct inode *inode,
 454                 const unsigned char *path, struct exfat_chain *dir,
 455                 struct exfat_uni_name *uni)
 456 {
 457         return __exfat_resolve_path(inode, path, dir, uni, 0);
 458 }
 459
 460 static inline int exfat_resolve_path_for_lookup(struct inode *inode,
 461                 const unsigned char *path, struct exfat_chain *dir,
 462                 struct exfat_uni_name *uni)
 463 {
 464         return __exfat_resolve_path(inode, path, dir, uni, 1);
 465 }
 466
 467 static inline loff_t exfat_make_i_pos(struct exfat_dir_entry *info)
 468 {
 469         return ((loff_t) info->dir.dir << 32) | (info->entry & 0xffffffff);
 470 }
 471
 472 static int exfat_add_entry(struct inode *inode, const char *path,
 473                 struct exfat_chain *p_dir, unsigned int type,
 474                 struct exfat_dir_entry *info)
 475 {
 476         int ret, dentry, num_entries;
 477         struct super_block *sb = inode->i_sb;
 478         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 479         struct exfat_uni_name uniname;
 480         struct exfat_chain clu;
 481         int clu_size = 0;
 482         unsigned int start_clu = EXFAT_FREE_CLUSTER;
 483
 484         ret = exfat_resolve_path(inode, path, p_dir, &uniname);
 485         if (ret)
 486                 goto out;
 487
 488         num_entries = exfat_calc_num_entries(&uniname);
 489         if (num_entries < 0) {
 490                 ret = num_entries;
 491                 goto out;
 492         }
 493
 494         /* exfat_find_empty_entry must be called before alloc_cluster() */
 495         dentry = exfat_find_empty_entry(inode, p_dir, num_entries);
 496         if (dentry < 0) {
 497                 ret = dentry; /* -EIO or -ENOSPC */
 498                 goto out;
 499         }
 500
 501         if (type == TYPE_DIR) {
 502                 ret = exfat_alloc_new_dir(inode, &clu);
 503                 if (ret)
 504                         goto out;
 505                 start_clu = clu.dir;
 506                 clu_size = sbi->cluster_size;
 507         }
 508
 509         /* update the directory entry */
 510         /* fill the dos name directory entry information of the created file.
 511          * the first cluster is not determined yet. (0)
 512          */
 513         ret = exfat_init_dir_entry(inode, p_dir, dentry, type,
 514                 start_clu, clu_size);
 515         if (ret)
 516                 goto out;
 517
 518         ret = exfat_init_ext_entry(inode, p_dir, dentry, num_entries, &uniname);
 519         if (ret)
 520                 goto out;
 521
 522         info->dir = *p_dir;
 523         info->entry = dentry;
 524         info->flags = ALLOC_NO_FAT_CHAIN;
 525         info->type = type;
 526
 527         if (type == TYPE_FILE) {
 528                 info->attr = ATTR_ARCHIVE;
 529                 info->start_clu = EXFAT_EOF_CLUSTER;
 530                 info->size = 0;
 531                 info->num_subdirs = 0;
 532         } else {
 533                 info->attr = ATTR_SUBDIR;
 534                 info->start_clu = start_clu;
 535                 info->size = clu_size;
 536                 info->num_subdirs = EXFAT_MIN_SUBDIR;
 537         }
 538         memset(&info->crtime, 0, sizeof(info->crtime));
 539         memset(&info->mtime, 0, sizeof(info->mtime));
 540         memset(&info->atime, 0, sizeof(info->atime));
 541 out:
 542         return ret;
 543 }
 544
 545 static int exfat_create(struct user_namespace *mnt_userns, struct inode *dir,
 546                         struct dentry *dentry, umode_t mode, bool excl)
 547 {
 548         struct super_block *sb = dir->i_sb;
 549         struct inode *inode;
 550         struct exfat_chain cdir;
 551         struct exfat_dir_entry info;
 552         loff_t i_pos;
 553         int err;
 554
 555         mutex_lock(&EXFAT_SB(sb)->s_lock);
 556         exfat_set_volume_dirty(sb);
 557         err = exfat_add_entry(dir, dentry->d_name.name, &cdir, TYPE_FILE,
 558                 &info);
 559         if (err)
 560                 goto unlock;
 561
 562         inode_inc_iversion(dir);
 563         dir->i_ctime = dir->i_mtime = current_time(dir);
 564         if (IS_DIRSYNC(dir))
 565                 exfat_sync_inode(dir);
 566         else
 567                 mark_inode_dirty(dir);
 568
 569         i_pos = exfat_make_i_pos(&info);
 570         inode = exfat_build_inode(sb, &info, i_pos);
 571         err = PTR_ERR_OR_ZERO(inode);
 572         if (err)
 573                 goto unlock;
 574
 575         inode_inc_iversion(inode);
 576         inode->i_mtime = inode->i_atime = inode->i_ctime =
 577                 EXFAT_I(inode)->i_crtime = current_time(inode);
 578         exfat_truncate_atime(&inode->i_atime);
 579         /* timestamp is already written, so mark_inode_dirty() is unneeded. */
 580
 581         d_instantiate(dentry, inode);
 582 unlock:
 583         mutex_unlock(&EXFAT_SB(sb)->s_lock);
 584         return err;
 585 }
 586
 587 /* lookup a file */
 588 static int exfat_find(struct inode *dir, struct qstr *qname,
 589                 struct exfat_dir_entry *info)
 590 {
 591         int ret, dentry, num_entries, count;
 592         struct exfat_chain cdir;
 593         struct exfat_uni_name uni_name;
 594         struct super_block *sb = dir->i_sb;
 595         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 596         struct exfat_inode_info *ei = EXFAT_I(dir);
 597         struct exfat_dentry *ep, *ep2;
 598         struct exfat_entry_set_cache *es;
 599         /* for optimized dir & entry to prevent long traverse of cluster chain */
 600         struct exfat_hint hint_opt;
 601
 602         if (qname->len == 0)
 603                 return -ENOENT;
 604
 605         /* check the validity of directory name in the given pathname */
 606         ret = exfat_resolve_path_for_lookup(dir, qname->name, &cdir, &uni_name);
 607         if (ret)
 608                 return ret;
 609
 610         num_entries = exfat_calc_num_entries(&uni_name);
 611         if (num_entries < 0)
 612                 return num_entries;
 613
 614         /* check the validation of hint_stat and initialize it if required */
 615         if (ei->version != (inode_peek_iversion_raw(dir) & 0xffffffff)) {
 616                 ei->hint_stat.clu = cdir.dir;
 617                 ei->hint_stat.eidx = 0;
 618                 ei->version = (inode_peek_iversion_raw(dir) & 0xffffffff);
 619                 ei->hint_femp.eidx = EXFAT_HINT_NONE;
 620         }
 621
 622         /* search the file name for directories */
 623         dentry = exfat_find_dir_entry(sb, ei, &cdir, &uni_name,
 624                         num_entries, TYPE_ALL, &hint_opt);
 625
 626         if (dentry < 0)
 627                 return dentry; /* -error value */
 628
 629         info->dir = cdir;
 630         info->entry = dentry;
 631         info->num_subdirs = 0;
 632
 633         /* adjust cdir to the optimized value */
 634         cdir.dir = hint_opt.clu;
 635         if (cdir.flags & ALLOC_NO_FAT_CHAIN)
 636                 cdir.size -= dentry / sbi->dentries_per_clu;
 637         dentry = hint_opt.eidx;
 638         es = exfat_get_dentry_set(sb, &cdir, dentry, ES_2_ENTRIES);
 639         if (!es)
 640                 return -EIO;
 641         ep = exfat_get_dentry_cached(es, 0);
 642         ep2 = exfat_get_dentry_cached(es, 1);
 643
 644         info->type = exfat_get_entry_type(ep);
 645         info->attr = le16_to_cpu(ep->dentry.file.attr);
 646         info->size = le64_to_cpu(ep2->dentry.stream.valid_size);
 647         if ((info->type == TYPE_FILE) && (info->size == 0)) {
 648                 info->flags = ALLOC_NO_FAT_CHAIN;
 649                 info->start_clu = EXFAT_EOF_CLUSTER;
 650         } else {
 651                 info->flags = ep2->dentry.stream.flags;
 652                 info->start_clu =
 653                         le32_to_cpu(ep2->dentry.stream.start_clu);
 654         }
 655
 656         exfat_get_entry_time(sbi, &info->crtime,
 657                              ep->dentry.file.create_tz,
 658                              ep->dentry.file.create_time,
 659                              ep->dentry.file.create_date,
 660                              ep->dentry.file.create_time_cs);
 661         exfat_get_entry_time(sbi, &info->mtime,
 662                              ep->dentry.file.modify_tz,
 663                              ep->dentry.file.modify_time,
 664                              ep->dentry.file.modify_date,
 665                              ep->dentry.file.modify_time_cs);
 666         exfat_get_entry_time(sbi, &info->atime,
 667                              ep->dentry.file.access_tz,
 668                              ep->dentry.file.access_time,
 669                              ep->dentry.file.access_date,
 670                              0);
 671         exfat_free_dentry_set(es, false);
 672
 673         if (ei->start_clu == EXFAT_FREE_CLUSTER) {
 674                 exfat_fs_error(sb,
 675                                "non-zero size file starts with zero cluster (size : %llu, p_dir : %u, entry : 0x%08x)",
 676                                i_size_read(dir), ei->dir.dir, ei->entry);
 677                 return -EIO;
 678         }
 679
 680         if (info->type == TYPE_DIR) {
 681                 exfat_chain_set(&cdir, info->start_clu,
 682                                 EXFAT_B_TO_CLU(info->size, sbi), info->flags);
 683                 count = exfat_count_dir_entries(sb, &cdir);
 684                 if (count < 0)
 685                         return -EIO;
 686
 687                 info->num_subdirs = count + EXFAT_MIN_SUBDIR;
 688         }
 689         return 0;
 690 }
 691
 692 static int exfat_d_anon_disconn(struct dentry *dentry)
 693 {
 694         return IS_ROOT(dentry) && (dentry->d_flags & DCACHE_DISCONNECTED);
 695 }
 696
 697 static struct dentry *exfat_lookup(struct inode *dir, struct dentry *dentry,
 698                 unsigned int flags)
 699 {
 700         struct super_block *sb = dir->i_sb;
 701         struct inode *inode;
 702         struct dentry *alias;
 703         struct exfat_dir_entry info;
 704         int err;
 705         loff_t i_pos;
 706         mode_t i_mode;
 707
 708         mutex_lock(&EXFAT_SB(sb)->s_lock);
 709         err = exfat_find(dir, &dentry->d_name, &info);
 710         if (err) {
 711                 if (err == -ENOENT) {
 712                         inode = NULL;
 713                         goto out;
 714                 }
 715                 goto unlock;
 716         }
 717
 718         i_pos = exfat_make_i_pos(&info);
 719         inode = exfat_build_inode(sb, &info, i_pos);
 720         err = PTR_ERR_OR_ZERO(inode);
 721         if (err)
 722                 goto unlock;
 723
 724         i_mode = inode->i_mode;
 725         alias = d_find_alias(inode);
 726
 727         /*
 728          * Checking "alias->d_parent == dentry->d_parent" to make sure
 729          * FS is not corrupted (especially double linked dir).
 730          */
 731         if (alias && alias->d_parent == dentry->d_parent &&
 732                         !exfat_d_anon_disconn(alias)) {
 733
 734                 /*
 735                  * Unhashed alias is able to exist because of revalidate()
 736                  * called by lookup_fast. You can easily make this status
 737                  * by calling create and lookup concurrently
 738                  * In such case, we reuse an alias instead of new dentry
 739                  */
 740                 if (d_unhashed(alias)) {
 741                         WARN_ON(alias->d_name.hash_len !=
 742                                 dentry->d_name.hash_len);
 743                         exfat_info(sb, "rehashed a dentry(%p) in read lookup",
 744                                    alias);
 745                         d_drop(dentry);
 746                         d_rehash(alias);
 747                 } else if (!S_ISDIR(i_mode)) {
 748                         /*
 749                          * This inode has non anonymous-DCACHE_DISCONNECTED
 750                          * dentry. This means, the user did ->lookup() by an
 751                          * another name (longname vs 8.3 alias of it) in past.
 752                          *
 753                          * Switch to new one for reason of locality if possible.
 754                          */
 755                         d_move(alias, dentry);
 756                 }
 757                 iput(inode);
 758                 mutex_unlock(&EXFAT_SB(sb)->s_lock);
 759                 return alias;
 760         }
 761         dput(alias);
 762 out:
 763         mutex_unlock(&EXFAT_SB(sb)->s_lock);
 764         if (!inode)
 765                 exfat_d_version_set(dentry, inode_query_iversion(dir));
 766
 767         return d_splice_alias(inode, dentry);
 768 unlock:
 769         mutex_unlock(&EXFAT_SB(sb)->s_lock);
 770         return ERR_PTR(err);
 771 }
 772
 773 /* remove an entry, BUT don't truncate */
 774 static int exfat_unlink(struct inode *dir, struct dentry *dentry)
 775 {
 776         struct exfat_chain cdir;
 777         struct exfat_dentry *ep;
 778         struct super_block *sb = dir->i_sb;
 779         struct inode *inode = dentry->d_inode;
 780         struct exfat_inode_info *ei = EXFAT_I(inode);
 781         struct buffer_head *bh;
 782         int num_entries, entry, err = 0;
 783
 784         mutex_lock(&EXFAT_SB(sb)->s_lock);
 785         exfat_chain_dup(&cdir, &ei->dir);
 786         entry = ei->entry;
 787         if (ei->dir.dir == DIR_DELETED) {
 788                 exfat_err(sb, "abnormal access to deleted dentry");
 789                 err = -ENOENT;
 790                 goto unlock;
 791         }
 792
 793         ep = exfat_get_dentry(sb, &cdir, entry, &bh);
 794         if (!ep) {
 795                 err = -EIO;
 796                 goto unlock;
 797         }
 798         num_entries = exfat_count_ext_entries(sb, &cdir, entry, ep);
 799         if (num_entries < 0) {
 800                 err = -EIO;
 801                 brelse(bh);
 802                 goto unlock;
 803         }
 804         num_entries++;
 805         brelse(bh);
 806
 807         exfat_set_volume_dirty(sb);
 808         /* update the directory entry */
 809         if (exfat_remove_entries(dir, &cdir, entry, 0, num_entries)) {
 810                 err = -EIO;
 811                 goto unlock;
 812         }
 813
 814         /* This doesn't modify ei */
 815         ei->dir.dir = DIR_DELETED;
 816
 817         inode_inc_iversion(dir);
 818         dir->i_mtime = dir->i_atime = current_time(dir);
 819         exfat_truncate_atime(&dir->i_atime);
 820         if (IS_DIRSYNC(dir))
 821                 exfat_sync_inode(dir);
 822         else
 823                 mark_inode_dirty(dir);
 824
 825         clear_nlink(inode);
 826         inode->i_mtime = inode->i_atime = current_time(inode);
 827         exfat_truncate_atime(&inode->i_atime);
 828         exfat_unhash_inode(inode);
 829         exfat_d_version_set(dentry, inode_query_iversion(dir));
 830 unlock:
 831         mutex_unlock(&EXFAT_SB(sb)->s_lock);
 832         return err;
 833 }
 834
 835 static int exfat_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
 836                        struct dentry *dentry, umode_t mode)
 837 {
 838         struct super_block *sb = dir->i_sb;
 839         struct inode *inode;
 840         struct exfat_dir_entry info;
 841         struct exfat_chain cdir;
 842         loff_t i_pos;
 843         int err;
 844
 845         mutex_lock(&EXFAT_SB(sb)->s_lock);
 846         exfat_set_volume_dirty(sb);
 847         err = exfat_add_entry(dir, dentry->d_name.name, &cdir, TYPE_DIR,
 848                 &info);
 849         if (err)
 850                 goto unlock;
 851
 852         inode_inc_iversion(dir);
 853         dir->i_ctime = dir->i_mtime = current_time(dir);
 854         if (IS_DIRSYNC(dir))
 855                 exfat_sync_inode(dir);
 856         else
 857                 mark_inode_dirty(dir);
 858         inc_nlink(dir);
 859
 860         i_pos = exfat_make_i_pos(&info);
 861         inode = exfat_build_inode(sb, &info, i_pos);
 862         err = PTR_ERR_OR_ZERO(inode);
 863         if (err)
 864                 goto unlock;
 865
 866         inode_inc_iversion(inode);
 867         inode->i_mtime = inode->i_atime = inode->i_ctime =
 868                 EXFAT_I(inode)->i_crtime = current_time(inode);
 869         exfat_truncate_atime(&inode->i_atime);
 870         /* timestamp is already written, so mark_inode_dirty() is unneeded. */
 871
 872         d_instantiate(dentry, inode);
 873
 874 unlock:
 875         mutex_unlock(&EXFAT_SB(sb)->s_lock);
 876         return err;
 877 }
 878
 879 static int exfat_check_dir_empty(struct super_block *sb,
 880                 struct exfat_chain *p_dir)
 881 {
 882         int i, dentries_per_clu;
 883         unsigned int type;
 884         struct exfat_chain clu;
 885         struct exfat_dentry *ep;
 886         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 887         struct buffer_head *bh;
 888
 889         dentries_per_clu = sbi->dentries_per_clu;
 890
 891         exfat_chain_dup(&clu, p_dir);
 892
 893         while (clu.dir != EXFAT_EOF_CLUSTER) {
 894                 for (i = 0; i < dentries_per_clu; i++) {
 895                         ep = exfat_get_dentry(sb, &clu, i, &bh);
 896                         if (!ep)
 897                                 return -EIO;
 898                         type = exfat_get_entry_type(ep);
 899                         brelse(bh);
 900                         if (type == TYPE_UNUSED)
 901                                 return 0;
 902
 903                         if (type != TYPE_FILE && type != TYPE_DIR)
 904                                 continue;
 905
 906                         return -ENOTEMPTY;
 907                 }
 908
 909                 if (clu.flags == ALLOC_NO_FAT_CHAIN) {
 910                         if (--clu.size > 0)
 911                                 clu.dir++;
 912                         else
 913                                 clu.dir = EXFAT_EOF_CLUSTER;
 914                 } else {
 915                         if (exfat_get_next_cluster(sb, &(clu.dir)))
 916                                 return -EIO;
 917                 }
 918         }
 919
 920         return 0;
 921 }
 922
 923 static int exfat_rmdir(struct inode *dir, struct dentry *dentry)
 924 {
 925         struct inode *inode = dentry->d_inode;
 926         struct exfat_dentry *ep;
 927         struct exfat_chain cdir, clu_to_free;
 928         struct super_block *sb = inode->i_sb;
 929         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 930         struct exfat_inode_info *ei = EXFAT_I(inode);
 931         struct buffer_head *bh;
 932         int num_entries, entry, err;
 933
 934         mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock);
 935
 936         exfat_chain_dup(&cdir, &ei->dir);
 937         entry = ei->entry;
 938
 939         if (ei->dir.dir == DIR_DELETED) {
 940                 exfat_err(sb, "abnormal access to deleted dentry");
 941                 err = -ENOENT;
 942                 goto unlock;
 943         }
 944
 945         exfat_chain_set(&clu_to_free, ei->start_clu,
 946                 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(inode), sbi), ei->flags);
 947
 948         err = exfat_check_dir_empty(sb, &clu_to_free);
 949         if (err) {
 950                 if (err == -EIO)
 951                         exfat_err(sb, "failed to exfat_check_dir_empty : err(%d)",
 952                                   err);
 953                 goto unlock;
 954         }
 955
 956         ep = exfat_get_dentry(sb, &cdir, entry, &bh);
 957         if (!ep) {
 958                 err = -EIO;
 959                 goto unlock;
 960         }
 961
 962         num_entries = exfat_count_ext_entries(sb, &cdir, entry, ep);
 963         if (num_entries < 0) {
 964                 err = -EIO;
 965                 brelse(bh);
 966                 goto unlock;
 967         }
 968         num_entries++;
 969         brelse(bh);
 970
 971         exfat_set_volume_dirty(sb);
 972         err = exfat_remove_entries(dir, &cdir, entry, 0, num_entries);
 973         if (err) {
 974                 exfat_err(sb, "failed to exfat_remove_entries : err(%d)", err);
 975                 goto unlock;
 976         }
 977         ei->dir.dir = DIR_DELETED;
 978
 979         inode_inc_iversion(dir);
 980         dir->i_mtime = dir->i_atime = current_time(dir);
 981         exfat_truncate_atime(&dir->i_atime);
 982         if (IS_DIRSYNC(dir))
 983                 exfat_sync_inode(dir);
 984         else
 985                 mark_inode_dirty(dir);
 986         drop_nlink(dir);
 987
 988         clear_nlink(inode);
 989         inode->i_mtime = inode->i_atime = current_time(inode);
 990         exfat_truncate_atime(&inode->i_atime);
 991         exfat_unhash_inode(inode);
 992         exfat_d_version_set(dentry, inode_query_iversion(dir));
 993 unlock:
 994         mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock);
 995         return err;
 996 }
 997
 998 static int exfat_rename_file(struct inode *inode, struct exfat_chain *p_dir,
 999                 int oldentry, struct exfat_uni_name *p_uniname,
1000                 struct exfat_inode_info *ei)
1001 {
1002         int ret, num_old_entries, num_new_entries;
1003         struct exfat_dentry *epold, *epnew;
1004         struct super_block *sb = inode->i_sb;
1005         struct buffer_head *new_bh, *old_bh;
1006         int sync = IS_DIRSYNC(inode);
1007
1008         epold = exfat_get_dentry(sb, p_dir, oldentry, &old_bh);
1009         if (!epold)
1010                 return -EIO;
1011
1012         num_old_entries = exfat_count_ext_entries(sb, p_dir, oldentry, epold);
1013         if (num_old_entries < 0)
1014                 return -EIO;
1015         num_old_entries++;
1016
1017         num_new_entries = exfat_calc_num_entries(p_uniname);
1018         if (num_new_entries < 0)
1019                 return num_new_entries;
1020
1021         if (num_old_entries < num_new_entries) {
1022                 int newentry;
1023
1024                 newentry =
1025                         exfat_find_empty_entry(inode, p_dir, num_new_entries);
1026                 if (newentry < 0)
1027                         return newentry; /* -EIO or -ENOSPC */
1028
1029                 epnew = exfat_get_dentry(sb, p_dir, newentry, &new_bh);
1030                 if (!epnew)
1031                         return -EIO;
1032
1033                 *epnew = *epold;
1034                 if (exfat_get_entry_type(epnew) == TYPE_FILE) {
1035                         epnew->dentry.file.attr |= cpu_to_le16(ATTR_ARCHIVE);
1036                         ei->attr |= ATTR_ARCHIVE;
1037                 }
1038                 exfat_update_bh(new_bh, sync);
1039                 brelse(old_bh);
1040                 brelse(new_bh);
1041
1042                 epold = exfat_get_dentry(sb, p_dir, oldentry + 1, &old_bh);
1043                 if (!epold)
1044                         return -EIO;
1045                 epnew = exfat_get_dentry(sb, p_dir, newentry + 1, &new_bh);
1046                 if (!epnew) {
1047                         brelse(old_bh);
1048                         return -EIO;
1049                 }
1050
1051                 *epnew = *epold;
1052                 exfat_update_bh(new_bh, sync);
1053                 brelse(old_bh);
1054                 brelse(new_bh);
1055
1056                 ret = exfat_init_ext_entry(inode, p_dir, newentry,
1057                         num_new_entries, p_uniname);
1058                 if (ret)
1059                         return ret;
1060
1061                 exfat_remove_entries(inode, p_dir, oldentry, 0,
1062                         num_old_entries);
1063                 ei->dir = *p_dir;
1064                 ei->entry = newentry;
1065         } else {
1066                 if (exfat_get_entry_type(epold) == TYPE_FILE) {
1067                         epold->dentry.file.attr |= cpu_to_le16(ATTR_ARCHIVE);
1068                         ei->attr |= ATTR_ARCHIVE;
1069                 }
1070                 exfat_update_bh(old_bh, sync);
1071                 brelse(old_bh);
1072                 ret = exfat_init_ext_entry(inode, p_dir, oldentry,
1073                         num_new_entries, p_uniname);
1074                 if (ret)
1075                         return ret;
1076
1077                 exfat_remove_entries(inode, p_dir, oldentry, num_new_entries,
1078                         num_old_entries);
1079         }
1080         return 0;
1081 }
1082
1083 static int exfat_move_file(struct inode *inode, struct exfat_chain *p_olddir,
1084                 int oldentry, struct exfat_chain *p_newdir,
1085                 struct exfat_uni_name *p_uniname, struct exfat_inode_info *ei)
1086 {
1087         int ret, newentry, num_new_entries, num_old_entries;
1088         struct exfat_dentry *epmov, *epnew;
1089         struct super_block *sb = inode->i_sb;
1090         struct buffer_head *mov_bh, *new_bh;
1091
1092         epmov = exfat_get_dentry(sb, p_olddir, oldentry, &mov_bh);
1093         if (!epmov)
1094                 return -EIO;
1095
1096         num_old_entries = exfat_count_ext_entries(sb, p_olddir, oldentry,
1097                 epmov);
1098         if (num_old_entries < 0)
1099                 return -EIO;
1100         num_old_entries++;
1101
1102         num_new_entries = exfat_calc_num_entries(p_uniname);
1103         if (num_new_entries < 0)
1104                 return num_new_entries;
1105
1106         newentry = exfat_find_empty_entry(inode, p_newdir, num_new_entries);
1107         if (newentry < 0)
1108                 return newentry; /* -EIO or -ENOSPC */
1109
1110         epnew = exfat_get_dentry(sb, p_newdir, newentry, &new_bh);
1111         if (!epnew)
1112                 return -EIO;
1113
1114         *epnew = *epmov;
1115         if (exfat_get_entry_type(epnew) == TYPE_FILE) {
1116                 epnew->dentry.file.attr |= cpu_to_le16(ATTR_ARCHIVE);
1117                 ei->attr |= ATTR_ARCHIVE;
1118         }
1119         exfat_update_bh(new_bh, IS_DIRSYNC(inode));
1120         brelse(mov_bh);
1121         brelse(new_bh);
1122
1123         epmov = exfat_get_dentry(sb, p_olddir, oldentry + 1, &mov_bh);
1124         if (!epmov)
1125                 return -EIO;
1126         epnew = exfat_get_dentry(sb, p_newdir, newentry + 1, &new_bh);
1127         if (!epnew) {
1128                 brelse(mov_bh);
1129                 return -EIO;
1130         }
1131
1132         *epnew = *epmov;
1133         exfat_update_bh(new_bh, IS_DIRSYNC(inode));
1134         brelse(mov_bh);
1135         brelse(new_bh);
1136
1137         ret = exfat_init_ext_entry(inode, p_newdir, newentry, num_new_entries,
1138                 p_uniname);
1139         if (ret)
1140                 return ret;
1141
1142         exfat_remove_entries(inode, p_olddir, oldentry, 0, num_old_entries);
1143
1144         exfat_chain_set(&ei->dir, p_newdir->dir, p_newdir->size,
1145                 p_newdir->flags);
1146
1147         ei->entry = newentry;
1148         return 0;
1149 }
1150
1151 /* rename or move a old file into a new file */
1152 static int __exfat_rename(struct inode *old_parent_inode,
1153                 struct exfat_inode_info *ei, struct inode *new_parent_inode,
1154                 struct dentry *new_dentry)
1155 {
1156         int ret;
1157         int dentry;
1158         struct exfat_chain olddir, newdir;
1159         struct exfat_chain *p_dir = NULL;
1160         struct exfat_uni_name uni_name;
1161         struct exfat_dentry *ep;
1162         struct super_block *sb = old_parent_inode->i_sb;
1163         struct exfat_sb_info *sbi = EXFAT_SB(sb);
1164         const unsigned char *new_path = new_dentry->d_name.name;
1165         struct inode *new_inode = new_dentry->d_inode;
1166         int num_entries;
1167         struct exfat_inode_info *new_ei = NULL;
1168         unsigned int new_entry_type = TYPE_UNUSED;
1169         int new_entry = 0;
1170         struct buffer_head *old_bh, *new_bh = NULL;
1171
1172         /* check the validity of pointer parameters */
1173         if (new_path == NULL || strlen(new_path) == 0)
1174                 return -EINVAL;
1175
1176         if (ei->dir.dir == DIR_DELETED) {
1177                 exfat_err(sb, "abnormal access to deleted source dentry");
1178                 return -ENOENT;
1179         }
1180
1181         exfat_chain_set(&olddir, EXFAT_I(old_parent_inode)->start_clu,
1182                 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(old_parent_inode), sbi),
1183                 EXFAT_I(old_parent_inode)->flags);
1184         dentry = ei->entry;
1185
1186         ep = exfat_get_dentry(sb, &olddir, dentry, &old_bh);
1187         if (!ep) {
1188                 ret = -EIO;
1189                 goto out;
1190         }
1191         brelse(old_bh);
1192
1193         /* check whether new dir is existing directory and empty */
1194         if (new_inode) {
1195                 ret = -EIO;
1196                 new_ei = EXFAT_I(new_inode);
1197
1198                 if (new_ei->dir.dir == DIR_DELETED) {
1199                         exfat_err(sb, "abnormal access to deleted target dentry");
1200                         goto out;
1201                 }
1202
1203                 p_dir = &(new_ei->dir);
1204                 new_entry = new_ei->entry;
1205                 ep = exfat_get_dentry(sb, p_dir, new_entry, &new_bh);
1206                 if (!ep)
1207                         goto out;
1208
1209                 new_entry_type = exfat_get_entry_type(ep);
1210                 brelse(new_bh);
1211
1212                 /* if new_inode exists, update ei */
1213                 if (new_entry_type == TYPE_DIR) {
1214                         struct exfat_chain new_clu;
1215
1216                         new_clu.dir = new_ei->start_clu;
1217                         new_clu.size =
1218                                 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode),
1219                                 sbi);
1220                         new_clu.flags = new_ei->flags;
1221
1222                         ret = exfat_check_dir_empty(sb, &new_clu);
1223                         if (ret)
1224                                 goto out;
1225                 }
1226         }
1227
1228         /* check the validity of directory name in the given new pathname */
1229         ret = exfat_resolve_path(new_parent_inode, new_path, &newdir,
1230                         &uni_name);
1231         if (ret)
1232                 goto out;
1233
1234         exfat_set_volume_dirty(sb);
1235
1236         if (olddir.dir == newdir.dir)
1237                 ret = exfat_rename_file(new_parent_inode, &olddir, dentry,
1238                                 &uni_name, ei);
1239         else
1240                 ret = exfat_move_file(new_parent_inode, &olddir, dentry,
1241                                 &newdir, &uni_name, ei);
1242
1243         if (!ret && new_inode) {
1244                 /* delete entries of new_dir */
1245                 ep = exfat_get_dentry(sb, p_dir, new_entry, &new_bh);
1246                 if (!ep) {
1247                         ret = -EIO;
1248                         goto del_out;
1249                 }
1250
1251                 num_entries = exfat_count_ext_entries(sb, p_dir, new_entry, ep);
1252                 if (num_entries < 0) {
1253                         ret = -EIO;
1254                         goto del_out;
1255                 }
1256                 brelse(new_bh);
1257
1258                 if (exfat_remove_entries(new_inode, p_dir, new_entry, 0,
1259                                 num_entries + 1)) {
1260                         ret = -EIO;
1261                         goto del_out;
1262                 }
1263
1264                 /* Free the clusters if new_inode is a dir(as if exfat_rmdir) */
1265                 if (new_entry_type == TYPE_DIR) {
1266                         /* new_ei, new_clu_to_free */
1267                         struct exfat_chain new_clu_to_free;
1268
1269                         exfat_chain_set(&new_clu_to_free, new_ei->start_clu,
1270                                 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode),
1271                                 sbi), new_ei->flags);
1272
1273                         if (exfat_free_cluster(new_inode, &new_clu_to_free)) {
1274                                 /* just set I/O error only */
1275                                 ret = -EIO;
1276                         }
1277
1278                         i_size_write(new_inode, 0);
1279                         new_ei->start_clu = EXFAT_EOF_CLUSTER;
1280                         new_ei->flags = ALLOC_NO_FAT_CHAIN;
1281                 }
1282 del_out:
1283                 /* Update new_inode ei
1284                  * Prevent syncing removed new_inode
1285                  * (new_ei is already initialized above code ("if (new_inode)")
1286                  */
1287                 new_ei->dir.dir = DIR_DELETED;
1288         }
1289 out:
1290         return ret;
1291 }
1292
1293 static int exfat_rename(struct user_namespace *mnt_userns,
1294                         struct inode *old_dir, struct dentry *old_dentry,
1295                         struct inode *new_dir, struct dentry *new_dentry,
1296                         unsigned int flags)
1297 {
1298         struct inode *old_inode, *new_inode;
1299         struct super_block *sb = old_dir->i_sb;
1300         loff_t i_pos;
1301         int err;
1302
1303         /*
1304          * The VFS already checks for existence, so for local filesystems
1305          * the RENAME_NOREPLACE implementation is equivalent to plain rename.
1306          * Don't support any other flags
1307          */
1308         if (flags & ~RENAME_NOREPLACE)
1309                 return -EINVAL;
1310
1311         mutex_lock(&EXFAT_SB(sb)->s_lock);
1312         old_inode = old_dentry->d_inode;
1313         new_inode = new_dentry->d_inode;
1314
1315         err = __exfat_rename(old_dir, EXFAT_I(old_inode), new_dir, new_dentry);
1316         if (err)
1317                 goto unlock;
1318
1319         inode_inc_iversion(new_dir);
1320         new_dir->i_ctime = new_dir->i_mtime = new_dir->i_atime =
1321                 EXFAT_I(new_dir)->i_crtime = current_time(new_dir);
1322         exfat_truncate_atime(&new_dir->i_atime);
1323         if (IS_DIRSYNC(new_dir))
1324                 exfat_sync_inode(new_dir);
1325         else
1326                 mark_inode_dirty(new_dir);
1327
1328         i_pos = ((loff_t)EXFAT_I(old_inode)->dir.dir << 32) |
1329                 (EXFAT_I(old_inode)->entry & 0xffffffff);
1330         exfat_unhash_inode(old_inode);
1331         exfat_hash_inode(old_inode, i_pos);
1332         if (IS_DIRSYNC(new_dir))
1333                 exfat_sync_inode(old_inode);
1334         else
1335                 mark_inode_dirty(old_inode);
1336
1337         if (S_ISDIR(old_inode->i_mode) && old_dir != new_dir) {
1338                 drop_nlink(old_dir);
1339                 if (!new_inode)
1340                         inc_nlink(new_dir);
1341         }
1342
1343         inode_inc_iversion(old_dir);
1344         old_dir->i_ctime = old_dir->i_mtime = current_time(old_dir);
1345         if (IS_DIRSYNC(old_dir))
1346                 exfat_sync_inode(old_dir);
1347         else
1348                 mark_inode_dirty(old_dir);
1349
1350         if (new_inode) {
1351                 exfat_unhash_inode(new_inode);
1352
1353                 /* skip drop_nlink if new_inode already has been dropped */
1354                 if (new_inode->i_nlink) {
1355                         drop_nlink(new_inode);
1356                         if (S_ISDIR(new_inode->i_mode))
1357                                 drop_nlink(new_inode);
1358                 } else {
1359                         exfat_warn(sb, "abnormal access to an inode dropped");
1360                         WARN_ON(new_inode->i_nlink == 0);
1361                 }
1362                 new_inode->i_ctime = EXFAT_I(new_inode)->i_crtime =
1363                         current_time(new_inode);
1364         }
1365
1366 unlock:
1367         mutex_unlock(&EXFAT_SB(sb)->s_lock);
1368         return err;
1369 }
1370
1371 const struct inode_operations exfat_dir_inode_operations = {
1372         .create         = exfat_create,
1373         .lookup         = exfat_lookup,
1374         .unlink         = exfat_unlink,
1375         .mkdir          = exfat_mkdir,
1376         .rmdir          = exfat_rmdir,
1377         .rename         = exfat_rename,
1378         .setattr        = exfat_setattr,
1379         .getattr        = exfat_getattr,
1380 };