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 */
  69 static unsigned int exfat_striptail_len(unsigned int len, const char *name)
  70 {
  71         while (len && name[len - 1] == '.')
  72                 len--;
  73         return len;
  74 }
  75
  76 /*
  77  * Compute the hash for the exfat name corresponding to the dentry.  If the name
  78  * is invalid, we leave the hash code unchanged so that the existing dentry can
  79  * be used. The exfat fs routines will return ENOENT or EINVAL as appropriate.
  80  */
  81 static int exfat_d_hash(const struct dentry *dentry, struct qstr *qstr)
  82 {
  83         struct super_block *sb = dentry->d_sb;
  84         struct nls_table *t = EXFAT_SB(sb)->nls_io;
  85         const unsigned char *name = qstr->name;
  86         unsigned int len = exfat_striptail_len(qstr->len, qstr->name);
  87         unsigned long hash = init_name_hash(dentry);
  88         int i, charlen;
  89         wchar_t c;
  90
  91         for (i = 0; i < len; i += charlen) {
  92                 charlen = t->char2uni(&name[i], len - i, &c);
  93                 if (charlen < 0)
  94                         return charlen;
  95                 hash = partial_name_hash(exfat_toupper(sb, c), hash);
  96         }
  97
  98         qstr->hash = end_name_hash(hash);
  99         return 0;
 100 }
 101
 102 static int exfat_d_cmp(const struct dentry *dentry, unsigned int len,
 103                 const char *str, const struct qstr *name)
 104 {
 105         struct super_block *sb = dentry->d_sb;
 106         struct nls_table *t = EXFAT_SB(sb)->nls_io;
 107         unsigned int alen = exfat_striptail_len(name->len, name->name);
 108         unsigned int blen = exfat_striptail_len(len, str);
 109         wchar_t c1, c2;
 110         int charlen, i;
 111
 112         if (alen != blen)
 113                 return 1;
 114
 115         for (i = 0; i < len; i += charlen) {
 116                 charlen = t->char2uni(&name->name[i], alen - i, &c1);
 117                 if (charlen < 0)
 118                         return 1;
 119                 if (charlen != t->char2uni(&str[i], blen - i, &c2))
 120                         return 1;
 121
 122                 if (exfat_toupper(sb, c1) != exfat_toupper(sb, c2))
 123                         return 1;
 124         }
 125
 126         return 0;
 127 }
 128
 129 const struct dentry_operations exfat_dentry_ops = {
 130         .d_revalidate   = exfat_d_revalidate,
 131         .d_hash         = exfat_d_hash,
 132         .d_compare      = exfat_d_cmp,
 133 };
 134
 135 static int exfat_utf8_d_hash(const struct dentry *dentry, struct qstr *qstr)
 136 {
 137         struct super_block *sb = dentry->d_sb;
 138         const unsigned char *name = qstr->name;
 139         unsigned int len = exfat_striptail_len(qstr->len, qstr->name);
 140         unsigned long hash = init_name_hash(dentry);
 141         int i, charlen;
 142         unicode_t u;
 143
 144         for (i = 0; i < len; i += charlen) {
 145                 charlen = utf8_to_utf32(&name[i], len - i, &u);
 146                 if (charlen < 0)
 147                         return charlen;
 148
 149                 /*
 150                  * exfat_toupper() works only for code points up to the U+FFFF.
 151                  */
 152                 hash = partial_name_hash(u <= 0xFFFF ? exfat_toupper(sb, u) : u,
 153                                          hash);
 154         }
 155
 156         qstr->hash = end_name_hash(hash);
 157         return 0;
 158 }
 159
 160 static int exfat_utf8_d_cmp(const struct dentry *dentry, unsigned int len,
 161                 const char *str, const struct qstr *name)
 162 {
 163         struct super_block *sb = dentry->d_sb;
 164         unsigned int alen = exfat_striptail_len(name->len, name->name);
 165         unsigned int blen = exfat_striptail_len(len, str);
 166         unicode_t u_a, u_b;
 167         int charlen, i;
 168
 169         if (alen != blen)
 170                 return 1;
 171
 172         for (i = 0; i < alen; i += charlen) {
 173                 charlen = utf8_to_utf32(&name->name[i], alen - i, &u_a);
 174                 if (charlen < 0)
 175                         return 1;
 176                 if (charlen != utf8_to_utf32(&str[i], blen - i, &u_b))
 177                         return 1;
 178
 179                 if (u_a <= 0xFFFF && u_b <= 0xFFFF) {
 180                         if (exfat_toupper(sb, u_a) != exfat_toupper(sb, u_b))
 181                                 return 1;
 182                 } else {
 183                         if (u_a != u_b)
 184                                 return 1;
 185                 }
 186         }
 187
 188         return 0;
 189 }
 190
 191 const struct dentry_operations exfat_utf8_dentry_ops = {
 192         .d_revalidate   = exfat_d_revalidate,
 193         .d_hash         = exfat_utf8_d_hash,
 194         .d_compare      = exfat_utf8_d_cmp,
 195 };
 196
 197 /* used only in search empty_slot() */
 198 #define CNT_UNUSED_NOHIT        (-1)
 199 #define CNT_UNUSED_HIT          (-2)
 200 /* search EMPTY CONTINUOUS "num_entries" entries */
 201 static int exfat_search_empty_slot(struct super_block *sb,
 202                 struct exfat_hint_femp *hint_femp, struct exfat_chain *p_dir,
 203                 int num_entries)
 204 {
 205         int i, dentry, num_empty = 0;
 206         int dentries_per_clu;
 207         unsigned int type;
 208         struct exfat_chain clu;
 209         struct exfat_dentry *ep;
 210         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 211         struct buffer_head *bh;
 212
 213         dentries_per_clu = sbi->dentries_per_clu;
 214
 215         if (hint_femp->eidx != EXFAT_HINT_NONE) {
 216                 dentry = hint_femp->eidx;
 217                 if (num_entries <= hint_femp->count) {
 218                         hint_femp->eidx = EXFAT_HINT_NONE;
 219                         return dentry;
 220                 }
 221
 222                 exfat_chain_dup(&clu, &hint_femp->cur);
 223         } else {
 224                 exfat_chain_dup(&clu, p_dir);
 225                 dentry = 0;
 226         }
 227
 228         while (clu.dir != EXFAT_EOF_CLUSTER) {
 229                 i = dentry & (dentries_per_clu - 1);
 230
 231                 for (; i < dentries_per_clu; i++, dentry++) {
 232                         ep = exfat_get_dentry(sb, &clu, i, &bh, NULL);
 233                         if (!ep)
 234                                 return -EIO;
 235                         type = exfat_get_entry_type(ep);
 236                         brelse(bh);
 237
 238                         if (type == TYPE_UNUSED || type == TYPE_DELETED) {
 239                                 num_empty++;
 240                                 if (hint_femp->eidx == EXFAT_HINT_NONE) {
 241                                         hint_femp->eidx = dentry;
 242                                         hint_femp->count = CNT_UNUSED_NOHIT;
 243                                         exfat_chain_set(&hint_femp->cur,
 244                                                 clu.dir, clu.size, clu.flags);
 245                                 }
 246
 247                                 if (type == TYPE_UNUSED &&
 248                                     hint_femp->count != CNT_UNUSED_HIT)
 249                                         hint_femp->count = CNT_UNUSED_HIT;
 250                         } else {
 251                                 if (hint_femp->eidx != EXFAT_HINT_NONE &&
 252                                     hint_femp->count == CNT_UNUSED_HIT) {
 253                                         /* unused empty group means
 254                                          * an empty group which includes
 255                                          * unused dentry
 256                                          */
 257                                         exfat_fs_error(sb,
 258                                                 "found bogus dentry(%d) beyond unused empty group(%d) (start_clu : %u, cur_clu : %u)",
 259                                                 dentry, hint_femp->eidx,
 260                                                 p_dir->dir, clu.dir);
 261                                         return -EIO;
 262                                 }
 263
 264                                 num_empty = 0;
 265                                 hint_femp->eidx = EXFAT_HINT_NONE;
 266                         }
 267
 268                         if (num_empty >= num_entries) {
 269                                 /* found and invalidate hint_femp */
 270                                 hint_femp->eidx = EXFAT_HINT_NONE;
 271                                 return (dentry - (num_entries - 1));
 272                         }
 273                 }
 274
 275                 if (clu.flags == ALLOC_NO_FAT_CHAIN) {
 276                         if (--clu.size > 0)
 277                                 clu.dir++;
 278                         else
 279                                 clu.dir = EXFAT_EOF_CLUSTER;
 280                 } else {
 281                         if (exfat_get_next_cluster(sb, &clu.dir))
 282                                 return -EIO;
 283                 }
 284         }
 285
 286         return -ENOSPC;
 287 }
 288
 289 static int exfat_check_max_dentries(struct inode *inode)
 290 {
 291         if (EXFAT_B_TO_DEN(i_size_read(inode)) >= MAX_EXFAT_DENTRIES) {
 292                 /*
 293                  * exFAT spec allows a dir to grow up to 8388608(256MB)
 294                  * dentries
 295                  */
 296                 return -ENOSPC;
 297         }
 298         return 0;
 299 }
 300
 301 /* find empty directory entry.
 302  * if there isn't any empty slot, expand cluster chain.
 303  */
 304 static int exfat_find_empty_entry(struct inode *inode,
 305                 struct exfat_chain *p_dir, int num_entries)
 306 {
 307         int dentry;
 308         unsigned int ret, last_clu;
 309         sector_t sector;
 310         loff_t size = 0;
 311         struct exfat_chain clu;
 312         struct exfat_dentry *ep = NULL;
 313         struct super_block *sb = inode->i_sb;
 314         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 315         struct exfat_inode_info *ei = EXFAT_I(inode);
 316         struct exfat_hint_femp hint_femp;
 317
 318         hint_femp.eidx = EXFAT_HINT_NONE;
 319
 320         if (ei->hint_femp.eidx != EXFAT_HINT_NONE) {
 321                 hint_femp = ei->hint_femp;
 322                 ei->hint_femp.eidx = EXFAT_HINT_NONE;
 323         }
 324
 325         while ((dentry = exfat_search_empty_slot(sb, &hint_femp, p_dir,
 326                                         num_entries)) < 0) {
 327                 if (dentry == -EIO)
 328                         break;
 329
 330                 if (exfat_check_max_dentries(inode))
 331                         return -ENOSPC;
 332
 333                 /* we trust p_dir->size regardless of FAT type */
 334                 if (exfat_find_last_cluster(sb, p_dir, &last_clu))
 335                         return -EIO;
 336
 337                 /*
 338                  * Allocate new cluster to this directory
 339                  */
 340                 exfat_chain_set(&clu, last_clu + 1, 0, p_dir->flags);
 341
 342                 /* allocate a cluster */
 343                 ret = exfat_alloc_cluster(inode, 1, &clu, IS_DIRSYNC(inode));
 344                 if (ret)
 345                         return ret;
 346
 347                 if (exfat_zeroed_cluster(inode, clu.dir))
 348                         return -EIO;
 349
 350                 /* append to the FAT chain */
 351                 if (clu.flags != p_dir->flags) {
 352                         /* no-fat-chain bit is disabled,
 353                          * so fat-chain should be synced with alloc-bitmap
 354                          */
 355                         exfat_chain_cont_cluster(sb, p_dir->dir, p_dir->size);
 356                         p_dir->flags = ALLOC_FAT_CHAIN;
 357                         hint_femp.cur.flags = ALLOC_FAT_CHAIN;
 358                 }
 359
 360                 if (clu.flags == ALLOC_FAT_CHAIN)
 361                         if (exfat_ent_set(sb, last_clu, clu.dir))
 362                                 return -EIO;
 363
 364                 if (hint_femp.eidx == EXFAT_HINT_NONE) {
 365                         /* the special case that new dentry
 366                          * should be allocated from the start of new cluster
 367                          */
 368                         hint_femp.eidx = EXFAT_B_TO_DEN_IDX(p_dir->size, sbi);
 369                         hint_femp.count = sbi->dentries_per_clu;
 370
 371                         exfat_chain_set(&hint_femp.cur, clu.dir, 0, clu.flags);
 372                 }
 373                 hint_femp.cur.size++;
 374                 p_dir->size++;
 375                 size = EXFAT_CLU_TO_B(p_dir->size, sbi);
 376
 377                 /* update the directory entry */
 378                 if (p_dir->dir != sbi->root_dir) {
 379                         struct buffer_head *bh;
 380
 381                         ep = exfat_get_dentry(sb,
 382                                 &(ei->dir), ei->entry + 1, &bh, &sector);
 383                         if (!ep)
 384                                 return -EIO;
 385
 386                         ep->dentry.stream.valid_size = cpu_to_le64(size);
 387                         ep->dentry.stream.size = ep->dentry.stream.valid_size;
 388                         ep->dentry.stream.flags = p_dir->flags;
 389                         exfat_update_bh(bh, IS_DIRSYNC(inode));
 390                         brelse(bh);
 391                         if (exfat_update_dir_chksum(inode, &(ei->dir),
 392                             ei->entry))
 393                                 return -EIO;
 394                 }
 395
 396                 /* directory inode should be updated in here */
 397                 i_size_write(inode, size);
 398                 EXFAT_I(inode)->i_size_ondisk += sbi->cluster_size;
 399                 EXFAT_I(inode)->i_size_aligned += sbi->cluster_size;
 400                 EXFAT_I(inode)->flags = p_dir->flags;
 401                 inode->i_blocks += 1 << sbi->sect_per_clus_bits;
 402         }
 403
 404         return dentry;
 405 }
 406
 407 /*
 408  * Name Resolution Functions :
 409  * Zero if it was successful; otherwise nonzero.
 410  */
 411 static int __exfat_resolve_path(struct inode *inode, const unsigned char *path,
 412                 struct exfat_chain *p_dir, struct exfat_uni_name *p_uniname,
 413                 int lookup)
 414 {
 415         int namelen;
 416         int lossy = NLS_NAME_NO_LOSSY;
 417         struct super_block *sb = inode->i_sb;
 418         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 419         struct exfat_inode_info *ei = EXFAT_I(inode);
 420
 421         /* strip all trailing periods */
 422         namelen = exfat_striptail_len(strlen(path), path);
 423         if (!namelen)
 424                 return -ENOENT;
 425
 426         if (strlen(path) > (MAX_NAME_LENGTH * MAX_CHARSET_SIZE))
 427                 return -ENAMETOOLONG;
 428
 429         /*
 430          * strip all leading spaces :
 431          * "MS windows 7" supports leading spaces.
 432          * So we should skip this preprocessing for compatibility.
 433          */
 434
 435         /* file name conversion :
 436          * If lookup case, we allow bad-name for compatibility.
 437          */
 438         namelen = exfat_nls_to_utf16(sb, path, namelen, p_uniname,
 439                         &lossy);
 440         if (namelen < 0)
 441                 return namelen; /* return error value */
 442
 443         if ((lossy && !lookup) || !namelen)
 444                 return -EINVAL;
 445
 446         exfat_chain_set(p_dir, ei->start_clu,
 447                 EXFAT_B_TO_CLU(i_size_read(inode), sbi), ei->flags);
 448
 449         return 0;
 450 }
 451
 452 static inline int exfat_resolve_path(struct inode *inode,
 453                 const unsigned char *path, struct exfat_chain *dir,
 454                 struct exfat_uni_name *uni)
 455 {
 456         return __exfat_resolve_path(inode, path, dir, uni, 0);
 457 }
 458
 459 static inline int exfat_resolve_path_for_lookup(struct inode *inode,
 460                 const unsigned char *path, struct exfat_chain *dir,
 461                 struct exfat_uni_name *uni)
 462 {
 463         return __exfat_resolve_path(inode, path, dir, uni, 1);
 464 }
 465
 466 static inline loff_t exfat_make_i_pos(struct exfat_dir_entry *info)
 467 {
 468         return ((loff_t) info->dir.dir << 32) | (info->entry & 0xffffffff);
 469 }
 470
 471 static int exfat_add_entry(struct inode *inode, const char *path,
 472                 struct exfat_chain *p_dir, unsigned int type,
 473                 struct exfat_dir_entry *info)
 474 {
 475         int ret, dentry, num_entries;
 476         struct super_block *sb = inode->i_sb;
 477         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 478         struct exfat_uni_name uniname;
 479         struct exfat_chain clu;
 480         int clu_size = 0;
 481         unsigned int start_clu = EXFAT_FREE_CLUSTER;
 482
 483         ret = exfat_resolve_path(inode, path, p_dir, &uniname);
 484         if (ret)
 485                 goto out;
 486
 487         num_entries = exfat_calc_num_entries(&uniname);
 488         if (num_entries < 0) {
 489                 ret = num_entries;
 490                 goto out;
 491         }
 492
 493         /* exfat_find_empty_entry must be called before alloc_cluster() */
 494         dentry = exfat_find_empty_entry(inode, p_dir, num_entries);
 495         if (dentry < 0) {
 496                 ret = dentry; /* -EIO or -ENOSPC */
 497                 goto out;
 498         }
 499
 500         if (type == TYPE_DIR) {
 501                 ret = exfat_alloc_new_dir(inode, &clu);
 502                 if (ret)
 503                         goto out;
 504                 start_clu = clu.dir;
 505                 clu_size = sbi->cluster_size;
 506         }
 507
 508         /* update the directory entry */
 509         /* fill the dos name directory entry information of the created file.
 510          * the first cluster is not determined yet. (0)
 511          */
 512         ret = exfat_init_dir_entry(inode, p_dir, dentry, type,
 513                 start_clu, clu_size);
 514         if (ret)
 515                 goto out;
 516
 517         ret = exfat_init_ext_entry(inode, p_dir, dentry, num_entries, &uniname);
 518         if (ret)
 519                 goto out;
 520
 521         info->dir = *p_dir;
 522         info->entry = dentry;
 523         info->flags = ALLOC_NO_FAT_CHAIN;
 524         info->type = type;
 525
 526         if (type == TYPE_FILE) {
 527                 info->attr = ATTR_ARCHIVE;
 528                 info->start_clu = EXFAT_EOF_CLUSTER;
 529                 info->size = 0;
 530                 info->num_subdirs = 0;
 531         } else {
 532                 info->attr = ATTR_SUBDIR;
 533                 info->start_clu = start_clu;
 534                 info->size = clu_size;
 535                 info->num_subdirs = EXFAT_MIN_SUBDIR;
 536         }
 537         memset(&info->crtime, 0, sizeof(info->crtime));
 538         memset(&info->mtime, 0, sizeof(info->mtime));
 539         memset(&info->atime, 0, sizeof(info->atime));
 540 out:
 541         return ret;
 542 }
 543
 544 static int exfat_create(struct user_namespace *mnt_userns, struct inode *dir,
 545                         struct dentry *dentry, umode_t mode, bool excl)
 546 {
 547         struct super_block *sb = dir->i_sb;
 548         struct inode *inode;
 549         struct exfat_chain cdir;
 550         struct exfat_dir_entry info;
 551         loff_t i_pos;
 552         int err;
 553
 554         mutex_lock(&EXFAT_SB(sb)->s_lock);
 555         exfat_set_volume_dirty(sb);
 556         err = exfat_add_entry(dir, dentry->d_name.name, &cdir, TYPE_FILE,
 557                 &info);
 558         exfat_clear_volume_dirty(sb);
 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         sector_t sector;
 783         int num_entries, entry, err = 0;
 784
 785         mutex_lock(&EXFAT_SB(sb)->s_lock);
 786         exfat_chain_dup(&cdir, &ei->dir);
 787         entry = ei->entry;
 788         if (ei->dir.dir == DIR_DELETED) {
 789                 exfat_err(sb, "abnormal access to deleted dentry");
 790                 err = -ENOENT;
 791                 goto unlock;
 792         }
 793
 794         ep = exfat_get_dentry(sb, &cdir, entry, &bh, &sector);
 795         if (!ep) {
 796                 err = -EIO;
 797                 goto unlock;
 798         }
 799         num_entries = exfat_count_ext_entries(sb, &cdir, entry, ep);
 800         if (num_entries < 0) {
 801                 err = -EIO;
 802                 brelse(bh);
 803                 goto unlock;
 804         }
 805         num_entries++;
 806         brelse(bh);
 807
 808         exfat_set_volume_dirty(sb);
 809         /* update the directory entry */
 810         if (exfat_remove_entries(dir, &cdir, entry, 0, num_entries)) {
 811                 err = -EIO;
 812                 goto unlock;
 813         }
 814
 815         /* This doesn't modify ei */
 816         ei->dir.dir = DIR_DELETED;
 817         exfat_clear_volume_dirty(sb);
 818
 819         inode_inc_iversion(dir);
 820         dir->i_mtime = dir->i_atime = current_time(dir);
 821         exfat_truncate_atime(&dir->i_atime);
 822         if (IS_DIRSYNC(dir))
 823                 exfat_sync_inode(dir);
 824         else
 825                 mark_inode_dirty(dir);
 826
 827         clear_nlink(inode);
 828         inode->i_mtime = inode->i_atime = current_time(inode);
 829         exfat_truncate_atime(&inode->i_atime);
 830         exfat_unhash_inode(inode);
 831         exfat_d_version_set(dentry, inode_query_iversion(dir));
 832 unlock:
 833         mutex_unlock(&EXFAT_SB(sb)->s_lock);
 834         return err;
 835 }
 836
 837 static int exfat_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
 838                        struct dentry *dentry, umode_t mode)
 839 {
 840         struct super_block *sb = dir->i_sb;
 841         struct inode *inode;
 842         struct exfat_dir_entry info;
 843         struct exfat_chain cdir;
 844         loff_t i_pos;
 845         int err;
 846
 847         mutex_lock(&EXFAT_SB(sb)->s_lock);
 848         exfat_set_volume_dirty(sb);
 849         err = exfat_add_entry(dir, dentry->d_name.name, &cdir, TYPE_DIR,
 850                 &info);
 851         exfat_clear_volume_dirty(sb);
 852         if (err)
 853                 goto unlock;
 854
 855         inode_inc_iversion(dir);
 856         dir->i_ctime = dir->i_mtime = current_time(dir);
 857         if (IS_DIRSYNC(dir))
 858                 exfat_sync_inode(dir);
 859         else
 860                 mark_inode_dirty(dir);
 861         inc_nlink(dir);
 862
 863         i_pos = exfat_make_i_pos(&info);
 864         inode = exfat_build_inode(sb, &info, i_pos);
 865         err = PTR_ERR_OR_ZERO(inode);
 866         if (err)
 867                 goto unlock;
 868
 869         inode_inc_iversion(inode);
 870         inode->i_mtime = inode->i_atime = inode->i_ctime =
 871                 EXFAT_I(inode)->i_crtime = current_time(inode);
 872         exfat_truncate_atime(&inode->i_atime);
 873         /* timestamp is already written, so mark_inode_dirty() is unneeded. */
 874
 875         d_instantiate(dentry, inode);
 876
 877 unlock:
 878         mutex_unlock(&EXFAT_SB(sb)->s_lock);
 879         return err;
 880 }
 881
 882 static int exfat_check_dir_empty(struct super_block *sb,
 883                 struct exfat_chain *p_dir)
 884 {
 885         int i, dentries_per_clu;
 886         unsigned int type;
 887         struct exfat_chain clu;
 888         struct exfat_dentry *ep;
 889         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 890         struct buffer_head *bh;
 891
 892         dentries_per_clu = sbi->dentries_per_clu;
 893
 894         exfat_chain_dup(&clu, p_dir);
 895
 896         while (clu.dir != EXFAT_EOF_CLUSTER) {
 897                 for (i = 0; i < dentries_per_clu; i++) {
 898                         ep = exfat_get_dentry(sb, &clu, i, &bh, NULL);
 899                         if (!ep)
 900                                 return -EIO;
 901                         type = exfat_get_entry_type(ep);
 902                         brelse(bh);
 903                         if (type == TYPE_UNUSED)
 904                                 return 0;
 905
 906                         if (type != TYPE_FILE && type != TYPE_DIR)
 907                                 continue;
 908
 909                         return -ENOTEMPTY;
 910                 }
 911
 912                 if (clu.flags == ALLOC_NO_FAT_CHAIN) {
 913                         if (--clu.size > 0)
 914                                 clu.dir++;
 915                         else
 916                                 clu.dir = EXFAT_EOF_CLUSTER;
 917                 } else {
 918                         if (exfat_get_next_cluster(sb, &(clu.dir)))
 919                                 return -EIO;
 920                 }
 921         }
 922
 923         return 0;
 924 }
 925
 926 static int exfat_rmdir(struct inode *dir, struct dentry *dentry)
 927 {
 928         struct inode *inode = dentry->d_inode;
 929         struct exfat_dentry *ep;
 930         struct exfat_chain cdir, clu_to_free;
 931         struct super_block *sb = inode->i_sb;
 932         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 933         struct exfat_inode_info *ei = EXFAT_I(inode);
 934         struct buffer_head *bh;
 935         sector_t sector;
 936         int num_entries, entry, err;
 937
 938         mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock);
 939
 940         exfat_chain_dup(&cdir, &ei->dir);
 941         entry = ei->entry;
 942
 943         if (ei->dir.dir == DIR_DELETED) {
 944                 exfat_err(sb, "abnormal access to deleted dentry");
 945                 err = -ENOENT;
 946                 goto unlock;
 947         }
 948
 949         exfat_chain_set(&clu_to_free, ei->start_clu,
 950                 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(inode), sbi), ei->flags);
 951
 952         err = exfat_check_dir_empty(sb, &clu_to_free);
 953         if (err) {
 954                 if (err == -EIO)
 955                         exfat_err(sb, "failed to exfat_check_dir_empty : err(%d)",
 956                                   err);
 957                 goto unlock;
 958         }
 959
 960         ep = exfat_get_dentry(sb, &cdir, entry, &bh, &sector);
 961         if (!ep) {
 962                 err = -EIO;
 963                 goto unlock;
 964         }
 965
 966         num_entries = exfat_count_ext_entries(sb, &cdir, entry, ep);
 967         if (num_entries < 0) {
 968                 err = -EIO;
 969                 brelse(bh);
 970                 goto unlock;
 971         }
 972         num_entries++;
 973         brelse(bh);
 974
 975         exfat_set_volume_dirty(sb);
 976         err = exfat_remove_entries(dir, &cdir, entry, 0, num_entries);
 977         if (err) {
 978                 exfat_err(sb, "failed to exfat_remove_entries : err(%d)", err);
 979                 goto unlock;
 980         }
 981         ei->dir.dir = DIR_DELETED;
 982         exfat_clear_volume_dirty(sb);
 983
 984         inode_inc_iversion(dir);
 985         dir->i_mtime = dir->i_atime = current_time(dir);
 986         exfat_truncate_atime(&dir->i_atime);
 987         if (IS_DIRSYNC(dir))
 988                 exfat_sync_inode(dir);
 989         else
 990                 mark_inode_dirty(dir);
 991         drop_nlink(dir);
 992
 993         clear_nlink(inode);
 994         inode->i_mtime = inode->i_atime = current_time(inode);
 995         exfat_truncate_atime(&inode->i_atime);
 996         exfat_unhash_inode(inode);
 997         exfat_d_version_set(dentry, inode_query_iversion(dir));
 998 unlock:
 999         mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock);
1000         return err;
1001 }
1002
1003 static int exfat_rename_file(struct inode *inode, struct exfat_chain *p_dir,
1004                 int oldentry, struct exfat_uni_name *p_uniname,
1005                 struct exfat_inode_info *ei)
1006 {
1007         int ret, num_old_entries, num_new_entries;
1008         sector_t sector_old, sector_new;
1009         struct exfat_dentry *epold, *epnew;
1010         struct super_block *sb = inode->i_sb;
1011         struct buffer_head *new_bh, *old_bh;
1012         int sync = IS_DIRSYNC(inode);
1013
1014         epold = exfat_get_dentry(sb, p_dir, oldentry, &old_bh, &sector_old);
1015         if (!epold)
1016                 return -EIO;
1017
1018         num_old_entries = exfat_count_ext_entries(sb, p_dir, oldentry, epold);
1019         if (num_old_entries < 0)
1020                 return -EIO;
1021         num_old_entries++;
1022
1023         num_new_entries = exfat_calc_num_entries(p_uniname);
1024         if (num_new_entries < 0)
1025                 return num_new_entries;
1026
1027         if (num_old_entries < num_new_entries) {
1028                 int newentry;
1029
1030                 newentry =
1031                         exfat_find_empty_entry(inode, p_dir, num_new_entries);
1032                 if (newentry < 0)
1033                         return newentry; /* -EIO or -ENOSPC */
1034
1035                 epnew = exfat_get_dentry(sb, p_dir, newentry, &new_bh,
1036                         &sector_new);
1037                 if (!epnew)
1038                         return -EIO;
1039
1040                 *epnew = *epold;
1041                 if (exfat_get_entry_type(epnew) == TYPE_FILE) {
1042                         epnew->dentry.file.attr |= cpu_to_le16(ATTR_ARCHIVE);
1043                         ei->attr |= ATTR_ARCHIVE;
1044                 }
1045                 exfat_update_bh(new_bh, sync);
1046                 brelse(old_bh);
1047                 brelse(new_bh);
1048
1049                 epold = exfat_get_dentry(sb, p_dir, oldentry + 1, &old_bh,
1050                         &sector_old);
1051                 if (!epold)
1052                         return -EIO;
1053                 epnew = exfat_get_dentry(sb, p_dir, newentry + 1, &new_bh,
1054                         &sector_new);
1055                 if (!epnew) {
1056                         brelse(old_bh);
1057                         return -EIO;
1058                 }
1059
1060                 *epnew = *epold;
1061                 exfat_update_bh(new_bh, sync);
1062                 brelse(old_bh);
1063                 brelse(new_bh);
1064
1065                 ret = exfat_init_ext_entry(inode, p_dir, newentry,
1066                         num_new_entries, p_uniname);
1067                 if (ret)
1068                         return ret;
1069
1070                 exfat_remove_entries(inode, p_dir, oldentry, 0,
1071                         num_old_entries);
1072                 ei->entry = newentry;
1073         } else {
1074                 if (exfat_get_entry_type(epold) == TYPE_FILE) {
1075                         epold->dentry.file.attr |= cpu_to_le16(ATTR_ARCHIVE);
1076                         ei->attr |= ATTR_ARCHIVE;
1077                 }
1078                 exfat_update_bh(old_bh, sync);
1079                 brelse(old_bh);
1080                 ret = exfat_init_ext_entry(inode, p_dir, oldentry,
1081                         num_new_entries, p_uniname);
1082                 if (ret)
1083                         return ret;
1084
1085                 exfat_remove_entries(inode, p_dir, oldentry, num_new_entries,
1086                         num_old_entries);
1087         }
1088         return 0;
1089 }
1090
1091 static int exfat_move_file(struct inode *inode, struct exfat_chain *p_olddir,
1092                 int oldentry, struct exfat_chain *p_newdir,
1093                 struct exfat_uni_name *p_uniname, struct exfat_inode_info *ei)
1094 {
1095         int ret, newentry, num_new_entries, num_old_entries;
1096         sector_t sector_mov, sector_new;
1097         struct exfat_dentry *epmov, *epnew;
1098         struct super_block *sb = inode->i_sb;
1099         struct buffer_head *mov_bh, *new_bh;
1100
1101         epmov = exfat_get_dentry(sb, p_olddir, oldentry, &mov_bh, &sector_mov);
1102         if (!epmov)
1103                 return -EIO;
1104
1105         num_old_entries = exfat_count_ext_entries(sb, p_olddir, oldentry,
1106                 epmov);
1107         if (num_old_entries < 0)
1108                 return -EIO;
1109         num_old_entries++;
1110
1111         num_new_entries = exfat_calc_num_entries(p_uniname);
1112         if (num_new_entries < 0)
1113                 return num_new_entries;
1114
1115         newentry = exfat_find_empty_entry(inode, p_newdir, num_new_entries);
1116         if (newentry < 0)
1117                 return newentry; /* -EIO or -ENOSPC */
1118
1119         epnew = exfat_get_dentry(sb, p_newdir, newentry, &new_bh, &sector_new);
1120         if (!epnew)
1121                 return -EIO;
1122
1123         *epnew = *epmov;
1124         if (exfat_get_entry_type(epnew) == TYPE_FILE) {
1125                 epnew->dentry.file.attr |= cpu_to_le16(ATTR_ARCHIVE);
1126                 ei->attr |= ATTR_ARCHIVE;
1127         }
1128         exfat_update_bh(new_bh, IS_DIRSYNC(inode));
1129         brelse(mov_bh);
1130         brelse(new_bh);
1131
1132         epmov = exfat_get_dentry(sb, p_olddir, oldentry + 1, &mov_bh,
1133                 &sector_mov);
1134         if (!epmov)
1135                 return -EIO;
1136         epnew = exfat_get_dentry(sb, p_newdir, newentry + 1, &new_bh,
1137                 &sector_new);
1138         if (!epnew) {
1139                 brelse(mov_bh);
1140                 return -EIO;
1141         }
1142
1143         *epnew = *epmov;
1144         exfat_update_bh(new_bh, IS_DIRSYNC(inode));
1145         brelse(mov_bh);
1146         brelse(new_bh);
1147
1148         ret = exfat_init_ext_entry(inode, p_newdir, newentry, num_new_entries,
1149                 p_uniname);
1150         if (ret)
1151                 return ret;
1152
1153         exfat_remove_entries(inode, p_olddir, oldentry, 0, num_old_entries);
1154
1155         exfat_chain_set(&ei->dir, p_newdir->dir, p_newdir->size,
1156                 p_newdir->flags);
1157
1158         ei->entry = newentry;
1159         return 0;
1160 }
1161
1162 static void exfat_update_parent_info(struct exfat_inode_info *ei,
1163                 struct inode *parent_inode)
1164 {
1165         struct exfat_sb_info *sbi = EXFAT_SB(parent_inode->i_sb);
1166         struct exfat_inode_info *parent_ei = EXFAT_I(parent_inode);
1167         loff_t parent_isize = i_size_read(parent_inode);
1168
1169         /*
1170          * the problem that struct exfat_inode_info caches wrong parent info.
1171          *
1172          * because of flag-mismatch of ei->dir,
1173          * there is abnormal traversing cluster chain.
1174          */
1175         if (unlikely(parent_ei->flags != ei->dir.flags ||
1176                      parent_isize != EXFAT_CLU_TO_B(ei->dir.size, sbi) ||
1177                      parent_ei->start_clu != ei->dir.dir)) {
1178                 exfat_chain_set(&ei->dir, parent_ei->start_clu,
1179                         EXFAT_B_TO_CLU_ROUND_UP(parent_isize, sbi),
1180                         parent_ei->flags);
1181         }
1182 }
1183
1184 /* rename or move a old file into a new file */
1185 static int __exfat_rename(struct inode *old_parent_inode,
1186                 struct exfat_inode_info *ei, struct inode *new_parent_inode,
1187                 struct dentry *new_dentry)
1188 {
1189         int ret;
1190         int dentry;
1191         struct exfat_chain olddir, newdir;
1192         struct exfat_chain *p_dir = NULL;
1193         struct exfat_uni_name uni_name;
1194         struct exfat_dentry *ep;
1195         struct super_block *sb = old_parent_inode->i_sb;
1196         struct exfat_sb_info *sbi = EXFAT_SB(sb);
1197         const unsigned char *new_path = new_dentry->d_name.name;
1198         struct inode *new_inode = new_dentry->d_inode;
1199         int num_entries;
1200         struct exfat_inode_info *new_ei = NULL;
1201         unsigned int new_entry_type = TYPE_UNUSED;
1202         int new_entry = 0;
1203         struct buffer_head *old_bh, *new_bh = NULL;
1204
1205         /* check the validity of pointer parameters */
1206         if (new_path == NULL || strlen(new_path) == 0)
1207                 return -EINVAL;
1208
1209         if (ei->dir.dir == DIR_DELETED) {
1210                 exfat_err(sb, "abnormal access to deleted source dentry");
1211                 return -ENOENT;
1212         }
1213
1214         exfat_update_parent_info(ei, old_parent_inode);
1215
1216         exfat_chain_dup(&olddir, &ei->dir);
1217         dentry = ei->entry;
1218
1219         ep = exfat_get_dentry(sb, &olddir, dentry, &old_bh, NULL);
1220         if (!ep) {
1221                 ret = -EIO;
1222                 goto out;
1223         }
1224         brelse(old_bh);
1225
1226         /* check whether new dir is existing directory and empty */
1227         if (new_inode) {
1228                 ret = -EIO;
1229                 new_ei = EXFAT_I(new_inode);
1230
1231                 if (new_ei->dir.dir == DIR_DELETED) {
1232                         exfat_err(sb, "abnormal access to deleted target dentry");
1233                         goto out;
1234                 }
1235
1236                 exfat_update_parent_info(new_ei, new_parent_inode);
1237
1238                 p_dir = &(new_ei->dir);
1239                 new_entry = new_ei->entry;
1240                 ep = exfat_get_dentry(sb, p_dir, new_entry, &new_bh, NULL);
1241                 if (!ep)
1242                         goto out;
1243
1244                 new_entry_type = exfat_get_entry_type(ep);
1245                 brelse(new_bh);
1246
1247                 /* if new_inode exists, update ei */
1248                 if (new_entry_type == TYPE_DIR) {
1249                         struct exfat_chain new_clu;
1250
1251                         new_clu.dir = new_ei->start_clu;
1252                         new_clu.size =
1253                                 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode),
1254                                 sbi);
1255                         new_clu.flags = new_ei->flags;
1256
1257                         ret = exfat_check_dir_empty(sb, &new_clu);
1258                         if (ret)
1259                                 goto out;
1260                 }
1261         }
1262
1263         /* check the validity of directory name in the given new pathname */
1264         ret = exfat_resolve_path(new_parent_inode, new_path, &newdir,
1265                         &uni_name);
1266         if (ret)
1267                 goto out;
1268
1269         exfat_set_volume_dirty(sb);
1270
1271         if (olddir.dir == newdir.dir)
1272                 ret = exfat_rename_file(new_parent_inode, &olddir, dentry,
1273                                 &uni_name, ei);
1274         else
1275                 ret = exfat_move_file(new_parent_inode, &olddir, dentry,
1276                                 &newdir, &uni_name, ei);
1277
1278         if (!ret && new_inode) {
1279                 /* delete entries of new_dir */
1280                 ep = exfat_get_dentry(sb, p_dir, new_entry, &new_bh, NULL);
1281                 if (!ep) {
1282                         ret = -EIO;
1283                         goto del_out;
1284                 }
1285
1286                 num_entries = exfat_count_ext_entries(sb, p_dir, new_entry, ep);
1287                 if (num_entries < 0) {
1288                         ret = -EIO;
1289                         goto del_out;
1290                 }
1291                 brelse(new_bh);
1292
1293                 if (exfat_remove_entries(new_inode, p_dir, new_entry, 0,
1294                                 num_entries + 1)) {
1295                         ret = -EIO;
1296                         goto del_out;
1297                 }
1298
1299                 /* Free the clusters if new_inode is a dir(as if exfat_rmdir) */
1300                 if (new_entry_type == TYPE_DIR) {
1301                         /* new_ei, new_clu_to_free */
1302                         struct exfat_chain new_clu_to_free;
1303
1304                         exfat_chain_set(&new_clu_to_free, new_ei->start_clu,
1305                                 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode),
1306                                 sbi), new_ei->flags);
1307
1308                         if (exfat_free_cluster(new_inode, &new_clu_to_free)) {
1309                                 /* just set I/O error only */
1310                                 ret = -EIO;
1311                         }
1312
1313                         i_size_write(new_inode, 0);
1314                         new_ei->start_clu = EXFAT_EOF_CLUSTER;
1315                         new_ei->flags = ALLOC_NO_FAT_CHAIN;
1316                 }
1317 del_out:
1318                 /* Update new_inode ei
1319                  * Prevent syncing removed new_inode
1320                  * (new_ei is already initialized above code ("if (new_inode)")
1321                  */
1322                 new_ei->dir.dir = DIR_DELETED;
1323         }
1324         exfat_clear_volume_dirty(sb);
1325 out:
1326         return ret;
1327 }
1328
1329 static int exfat_rename(struct user_namespace *mnt_userns,
1330                         struct inode *old_dir, struct dentry *old_dentry,
1331                         struct inode *new_dir, struct dentry *new_dentry,
1332                         unsigned int flags)
1333 {
1334         struct inode *old_inode, *new_inode;
1335         struct super_block *sb = old_dir->i_sb;
1336         loff_t i_pos;
1337         int err;
1338
1339         /*
1340          * The VFS already checks for existence, so for local filesystems
1341          * the RENAME_NOREPLACE implementation is equivalent to plain rename.
1342          * Don't support any other flags
1343          */
1344         if (flags & ~RENAME_NOREPLACE)
1345                 return -EINVAL;
1346
1347         mutex_lock(&EXFAT_SB(sb)->s_lock);
1348         old_inode = old_dentry->d_inode;
1349         new_inode = new_dentry->d_inode;
1350
1351         err = __exfat_rename(old_dir, EXFAT_I(old_inode), new_dir, new_dentry);
1352         if (err)
1353                 goto unlock;
1354
1355         inode_inc_iversion(new_dir);
1356         new_dir->i_ctime = new_dir->i_mtime = new_dir->i_atime =
1357                 EXFAT_I(new_dir)->i_crtime = current_time(new_dir);
1358         exfat_truncate_atime(&new_dir->i_atime);
1359         if (IS_DIRSYNC(new_dir))
1360                 exfat_sync_inode(new_dir);
1361         else
1362                 mark_inode_dirty(new_dir);
1363
1364         i_pos = ((loff_t)EXFAT_I(old_inode)->dir.dir << 32) |
1365                 (EXFAT_I(old_inode)->entry & 0xffffffff);
1366         exfat_unhash_inode(old_inode);
1367         exfat_hash_inode(old_inode, i_pos);
1368         if (IS_DIRSYNC(new_dir))
1369                 exfat_sync_inode(old_inode);
1370         else
1371                 mark_inode_dirty(old_inode);
1372
1373         if (S_ISDIR(old_inode->i_mode) && old_dir != new_dir) {
1374                 drop_nlink(old_dir);
1375                 if (!new_inode)
1376                         inc_nlink(new_dir);
1377         }
1378
1379         inode_inc_iversion(old_dir);
1380         old_dir->i_ctime = old_dir->i_mtime = current_time(old_dir);
1381         if (IS_DIRSYNC(old_dir))
1382                 exfat_sync_inode(old_dir);
1383         else
1384                 mark_inode_dirty(old_dir);
1385
1386         if (new_inode) {
1387                 exfat_unhash_inode(new_inode);
1388
1389                 /* skip drop_nlink if new_inode already has been dropped */
1390                 if (new_inode->i_nlink) {
1391                         drop_nlink(new_inode);
1392                         if (S_ISDIR(new_inode->i_mode))
1393                                 drop_nlink(new_inode);
1394                 } else {
1395                         exfat_warn(sb, "abnormal access to an inode dropped");
1396                         WARN_ON(new_inode->i_nlink == 0);
1397                 }
1398                 new_inode->i_ctime = EXFAT_I(new_inode)->i_crtime =
1399                         current_time(new_inode);
1400         }
1401
1402 unlock:
1403         mutex_unlock(&EXFAT_SB(sb)->s_lock);
1404         return err;
1405 }
1406
1407 const struct inode_operations exfat_dir_inode_operations = {
1408         .create         = exfat_create,
1409         .lookup         = exfat_lookup,
1410         .unlink         = exfat_unlink,
1411         .mkdir          = exfat_mkdir,
1412         .rmdir          = exfat_rmdir,
1413         .rename         = exfat_rename,
1414         .setattr        = exfat_setattr,
1415         .getattr        = exfat_getattr,
1416 };