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                  * Convert to UTF-16: code points above U+FFFF are encoded as
 151                  * surrogate pairs.
 152                  * exfat_toupper() works only for code points up to the U+FFFF.
 153                  */
 154                 if (u > 0xFFFF) {
 155                         hash = partial_name_hash(exfat_high_surrogate(u), hash);
 156                         hash = partial_name_hash(exfat_low_surrogate(u), hash);
 157                 } else {
 158                         hash = partial_name_hash(exfat_toupper(sb, u), hash);
 159                 }
 160         }
 161
 162         qstr->hash = end_name_hash(hash);
 163         return 0;
 164 }
 165
 166 static int exfat_utf8_d_cmp(const struct dentry *dentry, unsigned int len,
 167                 const char *str, const struct qstr *name)
 168 {
 169         struct super_block *sb = dentry->d_sb;
 170         unsigned int alen = exfat_striptail_len(name->len, name->name);
 171         unsigned int blen = exfat_striptail_len(len, str);
 172         unicode_t u_a, u_b;
 173         int charlen, i;
 174
 175         if (alen != blen)
 176                 return 1;
 177
 178         for (i = 0; i < alen; i += charlen) {
 179                 charlen = utf8_to_utf32(&name->name[i], alen - i, &u_a);
 180                 if (charlen < 0)
 181                         return 1;
 182                 if (charlen != utf8_to_utf32(&str[i], blen - i, &u_b))
 183                         return 1;
 184
 185                 if (u_a <= 0xFFFF && u_b <= 0xFFFF) {
 186                         if (exfat_toupper(sb, u_a) != exfat_toupper(sb, u_b))
 187                                 return 1;
 188                 } else if (u_a > 0xFFFF && u_b > 0xFFFF) {
 189                         if (exfat_low_surrogate(u_a) !=
 190                                         exfat_low_surrogate(u_b) ||
 191                             exfat_high_surrogate(u_a) !=
 192                                         exfat_high_surrogate(u_b))
 193                                 return 1;
 194                 } else {
 195                         return 1;
 196                 }
 197         }
 198
 199         return 0;
 200 }
 201
 202 const struct dentry_operations exfat_utf8_dentry_ops = {
 203         .d_revalidate   = exfat_d_revalidate,
 204         .d_hash         = exfat_utf8_d_hash,
 205         .d_compare      = exfat_utf8_d_cmp,
 206 };
 207
 208 /* used only in search empty_slot() */
 209 #define CNT_UNUSED_NOHIT        (-1)
 210 #define CNT_UNUSED_HIT          (-2)
 211 /* search EMPTY CONTINUOUS "num_entries" entries */
 212 static int exfat_search_empty_slot(struct super_block *sb,
 213                 struct exfat_hint_femp *hint_femp, struct exfat_chain *p_dir,
 214                 int num_entries)
 215 {
 216         int i, dentry, num_empty = 0;
 217         int dentries_per_clu;
 218         unsigned int type;
 219         struct exfat_chain clu;
 220         struct exfat_dentry *ep;
 221         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 222         struct buffer_head *bh;
 223
 224         dentries_per_clu = sbi->dentries_per_clu;
 225
 226         if (hint_femp->eidx != EXFAT_HINT_NONE) {
 227                 dentry = hint_femp->eidx;
 228                 if (num_entries <= hint_femp->count) {
 229                         hint_femp->eidx = EXFAT_HINT_NONE;
 230                         return dentry;
 231                 }
 232
 233                 exfat_chain_dup(&clu, &hint_femp->cur);
 234         } else {
 235                 exfat_chain_dup(&clu, p_dir);
 236                 dentry = 0;
 237         }
 238
 239         while (clu.dir != EXFAT_EOF_CLUSTER) {
 240                 i = dentry & (dentries_per_clu - 1);
 241
 242                 for (; i < dentries_per_clu; i++, dentry++) {
 243                         ep = exfat_get_dentry(sb, &clu, i, &bh, NULL);
 244                         if (!ep)
 245                                 return -EIO;
 246                         type = exfat_get_entry_type(ep);
 247                         brelse(bh);
 248
 249                         if (type == TYPE_UNUSED || type == TYPE_DELETED) {
 250                                 num_empty++;
 251                                 if (hint_femp->eidx == EXFAT_HINT_NONE) {
 252                                         hint_femp->eidx = dentry;
 253                                         hint_femp->count = CNT_UNUSED_NOHIT;
 254                                         exfat_chain_set(&hint_femp->cur,
 255                                                 clu.dir, clu.size, clu.flags);
 256                                 }
 257
 258                                 if (type == TYPE_UNUSED &&
 259                                     hint_femp->count != CNT_UNUSED_HIT)
 260                                         hint_femp->count = CNT_UNUSED_HIT;
 261                         } else {
 262                                 if (hint_femp->eidx != EXFAT_HINT_NONE &&
 263                                     hint_femp->count == CNT_UNUSED_HIT) {
 264                                         /* unused empty group means
 265                                          * an empty group which includes
 266                                          * unused dentry
 267                                          */
 268                                         exfat_fs_error(sb,
 269                                                 "found bogus dentry(%d) beyond unused empty group(%d) (start_clu : %u, cur_clu : %u)",
 270                                                 dentry, hint_femp->eidx,
 271                                                 p_dir->dir, clu.dir);
 272                                         return -EIO;
 273                                 }
 274
 275                                 num_empty = 0;
 276                                 hint_femp->eidx = EXFAT_HINT_NONE;
 277                         }
 278
 279                         if (num_empty >= num_entries) {
 280                                 /* found and invalidate hint_femp */
 281                                 hint_femp->eidx = EXFAT_HINT_NONE;
 282                                 return (dentry - (num_entries - 1));
 283                         }
 284                 }
 285
 286                 if (clu.flags == ALLOC_NO_FAT_CHAIN) {
 287                         if (--clu.size > 0)
 288                                 clu.dir++;
 289                         else
 290                                 clu.dir = EXFAT_EOF_CLUSTER;
 291                 } else {
 292                         if (exfat_get_next_cluster(sb, &clu.dir))
 293                                 return -EIO;
 294                 }
 295         }
 296
 297         return -ENOSPC;
 298 }
 299
 300 static int exfat_check_max_dentries(struct inode *inode)
 301 {
 302         if (EXFAT_B_TO_DEN(i_size_read(inode)) >= MAX_EXFAT_DENTRIES) {
 303                 /*
 304                  * exFAT spec allows a dir to grow upto 8388608(256MB)
 305                  * dentries
 306                  */
 307                 return -ENOSPC;
 308         }
 309         return 0;
 310 }
 311
 312 /* find empty directory entry.
 313  * if there isn't any empty slot, expand cluster chain.
 314  */
 315 static int exfat_find_empty_entry(struct inode *inode,
 316                 struct exfat_chain *p_dir, int num_entries)
 317 {
 318         int dentry;
 319         unsigned int ret, last_clu;
 320         sector_t sector;
 321         loff_t size = 0;
 322         struct exfat_chain clu;
 323         struct exfat_dentry *ep = NULL;
 324         struct super_block *sb = inode->i_sb;
 325         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 326         struct exfat_inode_info *ei = EXFAT_I(inode);
 327         struct exfat_hint_femp hint_femp;
 328
 329         hint_femp.eidx = EXFAT_HINT_NONE;
 330
 331         if (ei->hint_femp.eidx != EXFAT_HINT_NONE) {
 332                 memcpy(&hint_femp, &ei->hint_femp,
 333                                 sizeof(struct exfat_hint_femp));
 334                 ei->hint_femp.eidx = EXFAT_HINT_NONE;
 335         }
 336
 337         while ((dentry = exfat_search_empty_slot(sb, &hint_femp, p_dir,
 338                                         num_entries)) < 0) {
 339                 if (dentry == -EIO)
 340                         break;
 341
 342                 if (exfat_check_max_dentries(inode))
 343                         return -ENOSPC;
 344
 345                 /* we trust p_dir->size regardless of FAT type */
 346                 if (exfat_find_last_cluster(sb, p_dir, &last_clu))
 347                         return -EIO;
 348
 349                 /*
 350                  * Allocate new cluster to this directory
 351                  */
 352                 exfat_chain_set(&clu, last_clu + 1, 0, p_dir->flags);
 353
 354                 /* allocate a cluster */
 355                 ret = exfat_alloc_cluster(inode, 1, &clu);
 356                 if (ret)
 357                         return ret;
 358
 359                 if (exfat_zeroed_cluster(inode, clu.dir))
 360                         return -EIO;
 361
 362                 /* append to the FAT chain */
 363                 if (clu.flags != p_dir->flags) {
 364                         /* no-fat-chain bit is disabled,
 365                          * so fat-chain should be synced with alloc-bitmap
 366                          */
 367                         exfat_chain_cont_cluster(sb, p_dir->dir, p_dir->size);
 368                         p_dir->flags = ALLOC_FAT_CHAIN;
 369                         hint_femp.cur.flags = ALLOC_FAT_CHAIN;
 370                 }
 371
 372                 if (clu.flags == ALLOC_FAT_CHAIN)
 373                         if (exfat_ent_set(sb, last_clu, clu.dir))
 374                                 return -EIO;
 375
 376                 if (hint_femp.eidx == EXFAT_HINT_NONE) {
 377                         /* the special case that new dentry
 378                          * should be allocated from the start of new cluster
 379                          */
 380                         hint_femp.eidx = EXFAT_B_TO_DEN_IDX(p_dir->size, sbi);
 381                         hint_femp.count = sbi->dentries_per_clu;
 382
 383                         exfat_chain_set(&hint_femp.cur, clu.dir, 0, clu.flags);
 384                 }
 385                 hint_femp.cur.size++;
 386                 p_dir->size++;
 387                 size = EXFAT_CLU_TO_B(p_dir->size, sbi);
 388
 389                 /* update the directory entry */
 390                 if (p_dir->dir != sbi->root_dir) {
 391                         struct buffer_head *bh;
 392
 393                         ep = exfat_get_dentry(sb,
 394                                 &(ei->dir), ei->entry + 1, &bh, &sector);
 395                         if (!ep)
 396                                 return -EIO;
 397
 398                         ep->dentry.stream.valid_size = cpu_to_le64(size);
 399                         ep->dentry.stream.size = ep->dentry.stream.valid_size;
 400                         ep->dentry.stream.flags = p_dir->flags;
 401                         exfat_update_bh(sb, bh, IS_DIRSYNC(inode));
 402                         brelse(bh);
 403                         if (exfat_update_dir_chksum(inode, &(ei->dir),
 404                             ei->entry))
 405                                 return -EIO;
 406                 }
 407
 408                 /* directory inode should be updated in here */
 409                 i_size_write(inode, size);
 410                 EXFAT_I(inode)->i_size_ondisk += sbi->cluster_size;
 411                 EXFAT_I(inode)->i_size_aligned += sbi->cluster_size;
 412                 EXFAT_I(inode)->flags = p_dir->flags;
 413                 inode->i_blocks += 1 << sbi->sect_per_clus_bits;
 414         }
 415
 416         return dentry;
 417 }
 418
 419 /*
 420  * Name Resolution Functions :
 421  * Zero if it was successful; otherwise nonzero.
 422  */
 423 static int __exfat_resolve_path(struct inode *inode, const unsigned char *path,
 424                 struct exfat_chain *p_dir, struct exfat_uni_name *p_uniname,
 425                 int lookup)
 426 {
 427         int namelen;
 428         int lossy = NLS_NAME_NO_LOSSY;
 429         struct super_block *sb = inode->i_sb;
 430         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 431         struct exfat_inode_info *ei = EXFAT_I(inode);
 432
 433         /* strip all trailing periods */
 434         namelen = exfat_striptail_len(strlen(path), path);
 435         if (!namelen)
 436                 return -ENOENT;
 437
 438         if (strlen(path) > (MAX_NAME_LENGTH * MAX_CHARSET_SIZE))
 439                 return -ENAMETOOLONG;
 440
 441         /*
 442          * strip all leading spaces :
 443          * "MS windows 7" supports leading spaces.
 444          * So we should skip this preprocessing for compatibility.
 445          */
 446
 447         /* file name conversion :
 448          * If lookup case, we allow bad-name for compatibility.
 449          */
 450         namelen = exfat_nls_to_utf16(sb, path, namelen, p_uniname,
 451                         &lossy);
 452         if (namelen < 0)
 453                 return namelen; /* return error value */
 454
 455         if ((lossy && !lookup) || !namelen)
 456                 return -EINVAL;
 457
 458         exfat_chain_set(p_dir, ei->start_clu,
 459                 EXFAT_B_TO_CLU(i_size_read(inode), sbi), ei->flags);
 460
 461         return 0;
 462 }
 463
 464 static inline int exfat_resolve_path(struct inode *inode,
 465                 const unsigned char *path, struct exfat_chain *dir,
 466                 struct exfat_uni_name *uni)
 467 {
 468         return __exfat_resolve_path(inode, path, dir, uni, 0);
 469 }
 470
 471 static inline int exfat_resolve_path_for_lookup(struct inode *inode,
 472                 const unsigned char *path, struct exfat_chain *dir,
 473                 struct exfat_uni_name *uni)
 474 {
 475         return __exfat_resolve_path(inode, path, dir, uni, 1);
 476 }
 477
 478 static inline loff_t exfat_make_i_pos(struct exfat_dir_entry *info)
 479 {
 480         return ((loff_t) info->dir.dir << 32) | (info->entry & 0xffffffff);
 481 }
 482
 483 static int exfat_add_entry(struct inode *inode, const char *path,
 484                 struct exfat_chain *p_dir, unsigned int type,
 485                 struct exfat_dir_entry *info)
 486 {
 487         int ret, dentry, num_entries;
 488         struct super_block *sb = inode->i_sb;
 489         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 490         struct exfat_uni_name uniname;
 491         struct exfat_chain clu;
 492         int clu_size = 0;
 493         unsigned int start_clu = EXFAT_FREE_CLUSTER;
 494
 495         ret = exfat_resolve_path(inode, path, p_dir, &uniname);
 496         if (ret)
 497                 goto out;
 498
 499         num_entries = exfat_calc_num_entries(&uniname);
 500         if (num_entries < 0) {
 501                 ret = num_entries;
 502                 goto out;
 503         }
 504
 505         /* exfat_find_empty_entry must be called before alloc_cluster() */
 506         dentry = exfat_find_empty_entry(inode, p_dir, num_entries);
 507         if (dentry < 0) {
 508                 ret = dentry; /* -EIO or -ENOSPC */
 509                 goto out;
 510         }
 511
 512         if (type == TYPE_DIR) {
 513                 ret = exfat_alloc_new_dir(inode, &clu);
 514                 if (ret)
 515                         goto out;
 516                 start_clu = clu.dir;
 517                 clu_size = sbi->cluster_size;
 518         }
 519
 520         /* update the directory entry */
 521         /* fill the dos name directory entry information of the created file.
 522          * the first cluster is not determined yet. (0)
 523          */
 524         ret = exfat_init_dir_entry(inode, p_dir, dentry, type,
 525                 start_clu, clu_size);
 526         if (ret)
 527                 goto out;
 528
 529         ret = exfat_init_ext_entry(inode, p_dir, dentry, num_entries, &uniname);
 530         if (ret)
 531                 goto out;
 532
 533         memcpy(&info->dir, p_dir, sizeof(struct exfat_chain));
 534         info->entry = dentry;
 535         info->flags = ALLOC_NO_FAT_CHAIN;
 536         info->type = type;
 537
 538         if (type == TYPE_FILE) {
 539                 info->attr = ATTR_ARCHIVE;
 540                 info->start_clu = EXFAT_EOF_CLUSTER;
 541                 info->size = 0;
 542                 info->num_subdirs = 0;
 543         } else {
 544                 int count;
 545                 struct exfat_chain cdir;
 546
 547                 info->attr = ATTR_SUBDIR;
 548                 info->start_clu = start_clu;
 549                 info->size = clu_size;
 550
 551                 exfat_chain_set(&cdir, info->start_clu,
 552                         EXFAT_B_TO_CLU(info->size, sbi), info->flags);
 553                 count = exfat_count_dir_entries(sb, &cdir);
 554                 if (count < 0)
 555                         return -EIO;
 556                 info->num_subdirs = count + EXFAT_MIN_SUBDIR;
 557         }
 558         memset(&info->crtime, 0, sizeof(info->crtime));
 559         memset(&info->mtime, 0, sizeof(info->mtime));
 560         memset(&info->atime, 0, sizeof(info->atime));
 561 out:
 562         return ret;
 563 }
 564
 565 static int exfat_create(struct inode *dir, struct dentry *dentry, umode_t mode,
 566                 bool excl)
 567 {
 568         struct super_block *sb = dir->i_sb;
 569         struct inode *inode;
 570         struct exfat_chain cdir;
 571         struct exfat_dir_entry info;
 572         loff_t i_pos;
 573         int err;
 574
 575         mutex_lock(&EXFAT_SB(sb)->s_lock);
 576         exfat_set_vol_flags(sb, VOL_DIRTY);
 577         err = exfat_add_entry(dir, dentry->d_name.name, &cdir, TYPE_FILE,
 578                 &info);
 579         exfat_set_vol_flags(sb, VOL_CLEAN);
 580         if (err)
 581                 goto unlock;
 582
 583         inode_inc_iversion(dir);
 584         dir->i_ctime = dir->i_mtime = current_time(dir);
 585         if (IS_DIRSYNC(dir))
 586                 exfat_sync_inode(dir);
 587         else
 588                 mark_inode_dirty(dir);
 589
 590         i_pos = exfat_make_i_pos(&info);
 591         inode = exfat_build_inode(sb, &info, i_pos);
 592         if (IS_ERR(inode))
 593                 goto unlock;
 594
 595         inode_inc_iversion(inode);
 596         inode->i_mtime = inode->i_atime = inode->i_ctime =
 597                 EXFAT_I(inode)->i_crtime = current_time(inode);
 598         exfat_truncate_atime(&inode->i_atime);
 599         /* timestamp is already written, so mark_inode_dirty() is unneeded. */
 600
 601         d_instantiate(dentry, inode);
 602 unlock:
 603         mutex_unlock(&EXFAT_SB(sb)->s_lock);
 604         return err;
 605 }
 606
 607 /* lookup a file */
 608 static int exfat_find(struct inode *dir, struct qstr *qname,
 609                 struct exfat_dir_entry *info)
 610 {
 611         int ret, dentry, num_entries, count;
 612         struct exfat_chain cdir;
 613         struct exfat_uni_name uni_name;
 614         struct exfat_dentry *ep, *ep2;
 615         struct exfat_entry_set_cache *es = NULL;
 616         struct super_block *sb = dir->i_sb;
 617         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 618         struct exfat_inode_info *ei = EXFAT_I(dir);
 619
 620         if (qname->len == 0)
 621                 return -ENOENT;
 622
 623         /* check the validity of directory name in the given pathname */
 624         ret = exfat_resolve_path_for_lookup(dir, qname->name, &cdir, &uni_name);
 625         if (ret)
 626                 return ret;
 627
 628         num_entries = exfat_calc_num_entries(&uni_name);
 629         if (num_entries < 0)
 630                 return num_entries;
 631
 632         /* check the validation of hint_stat and initialize it if required */
 633         if (ei->version != (inode_peek_iversion_raw(dir) & 0xffffffff)) {
 634                 ei->hint_stat.clu = cdir.dir;
 635                 ei->hint_stat.eidx = 0;
 636                 ei->version = (inode_peek_iversion_raw(dir) & 0xffffffff);
 637                 ei->hint_femp.eidx = EXFAT_HINT_NONE;
 638         }
 639
 640         /* search the file name for directories */
 641         dentry = exfat_find_dir_entry(sb, ei, &cdir, &uni_name,
 642                         num_entries, TYPE_ALL);
 643
 644         if ((dentry < 0) && (dentry != -EEXIST))
 645                 return dentry; /* -error value */
 646
 647         memcpy(&info->dir, &cdir.dir, sizeof(struct exfat_chain));
 648         info->entry = dentry;
 649         info->num_subdirs = 0;
 650
 651         /* root directory itself */
 652         if (unlikely(dentry == -EEXIST)) {
 653                 int num_clu = 0;
 654
 655                 info->type = TYPE_DIR;
 656                 info->attr = ATTR_SUBDIR;
 657                 info->flags = ALLOC_FAT_CHAIN;
 658                 info->start_clu = sbi->root_dir;
 659                 memset(&info->crtime, 0, sizeof(info->crtime));
 660                 memset(&info->mtime, 0, sizeof(info->mtime));
 661                 memset(&info->atime, 0, sizeof(info->atime));
 662
 663                 exfat_chain_set(&cdir, sbi->root_dir, 0, ALLOC_FAT_CHAIN);
 664                 if (exfat_count_num_clusters(sb, &cdir, &num_clu))
 665                         return -EIO;
 666                 info->size = num_clu << sbi->cluster_size_bits;
 667
 668                 count = exfat_count_dir_entries(sb, &cdir);
 669                 if (count < 0)
 670                         return -EIO;
 671
 672                 info->num_subdirs = count;
 673         } else {
 674                 es = exfat_get_dentry_set(sb, &cdir, dentry, ES_2_ENTRIES, &ep);
 675                 if (!es)
 676                         return -EIO;
 677                 ep2 = ep + 1;
 678
 679                 info->type = exfat_get_entry_type(ep);
 680                 info->attr = le16_to_cpu(ep->dentry.file.attr);
 681                 info->size = le64_to_cpu(ep2->dentry.stream.valid_size);
 682                 if ((info->type == TYPE_FILE) && (info->size == 0)) {
 683                         info->flags = ALLOC_NO_FAT_CHAIN;
 684                         info->start_clu = EXFAT_EOF_CLUSTER;
 685                 } else {
 686                         info->flags = ep2->dentry.stream.flags;
 687                         info->start_clu =
 688                                 le32_to_cpu(ep2->dentry.stream.start_clu);
 689                 }
 690
 691                 if (ei->start_clu == EXFAT_FREE_CLUSTER) {
 692                         exfat_fs_error(sb,
 693                                 "non-zero size file starts with zero cluster (size : %llu, p_dir : %u, entry : 0x%08x)",
 694                                 i_size_read(dir), ei->dir.dir, ei->entry);
 695                         kfree(es);
 696                         return -EIO;
 697                 }
 698
 699                 exfat_get_entry_time(sbi, &info->crtime,
 700                                 ep->dentry.file.create_tz,
 701                                 ep->dentry.file.create_time,
 702                                 ep->dentry.file.create_date,
 703                                 ep->dentry.file.create_time_ms);
 704                 exfat_get_entry_time(sbi, &info->mtime,
 705                                 ep->dentry.file.modify_tz,
 706                                 ep->dentry.file.modify_time,
 707                                 ep->dentry.file.modify_date,
 708                                 ep->dentry.file.modify_time_ms);
 709                 exfat_get_entry_time(sbi, &info->atime,
 710                                 ep->dentry.file.access_tz,
 711                                 ep->dentry.file.access_time,
 712                                 ep->dentry.file.access_date,
 713                                 0);
 714                 kfree(es);
 715
 716                 if (info->type == TYPE_DIR) {
 717                         exfat_chain_set(&cdir, info->start_clu,
 718                                 EXFAT_B_TO_CLU(info->size, sbi), info->flags);
 719                         count = exfat_count_dir_entries(sb, &cdir);
 720                         if (count < 0)
 721                                 return -EIO;
 722
 723                         info->num_subdirs = count + EXFAT_MIN_SUBDIR;
 724                 }
 725         }
 726         return 0;
 727 }
 728
 729 static int exfat_d_anon_disconn(struct dentry *dentry)
 730 {
 731         return IS_ROOT(dentry) && (dentry->d_flags & DCACHE_DISCONNECTED);
 732 }
 733
 734 static struct dentry *exfat_lookup(struct inode *dir, struct dentry *dentry,
 735                 unsigned int flags)
 736 {
 737         struct super_block *sb = dir->i_sb;
 738         struct inode *inode;
 739         struct dentry *alias;
 740         struct exfat_dir_entry info;
 741         int err;
 742         loff_t i_pos;
 743         mode_t i_mode;
 744
 745         mutex_lock(&EXFAT_SB(sb)->s_lock);
 746         err = exfat_find(dir, &dentry->d_name, &info);
 747         if (err) {
 748                 if (err == -ENOENT) {
 749                         inode = NULL;
 750                         goto out;
 751                 }
 752                 goto unlock;
 753         }
 754
 755         i_pos = exfat_make_i_pos(&info);
 756         inode = exfat_build_inode(sb, &info, i_pos);
 757         if (IS_ERR(inode)) {
 758                 err = PTR_ERR(inode);
 759                 goto unlock;
 760         }
 761
 762         i_mode = inode->i_mode;
 763         alias = d_find_alias(inode);
 764
 765         /*
 766          * Checking "alias->d_parent == dentry->d_parent" to make sure
 767          * FS is not corrupted (especially double linked dir).
 768          */
 769         if (alias && alias->d_parent == dentry->d_parent &&
 770                         !exfat_d_anon_disconn(alias)) {
 771
 772                 /*
 773                  * Unhashed alias is able to exist because of revalidate()
 774                  * called by lookup_fast. You can easily make this status
 775                  * by calling create and lookup concurrently
 776                  * In such case, we reuse an alias instead of new dentry
 777                  */
 778                 if (d_unhashed(alias)) {
 779                         WARN_ON(alias->d_name.hash_len !=
 780                                 dentry->d_name.hash_len);
 781                         exfat_msg(sb, KERN_INFO,
 782                                 "rehashed a dentry(%p) in read lookup", alias);
 783                         d_drop(dentry);
 784                         d_rehash(alias);
 785                 } else if (!S_ISDIR(i_mode)) {
 786                         /*
 787                          * This inode has non anonymous-DCACHE_DISCONNECTED
 788                          * dentry. This means, the user did ->lookup() by an
 789                          * another name (longname vs 8.3 alias of it) in past.
 790                          *
 791                          * Switch to new one for reason of locality if possible.
 792                          */
 793                         d_move(alias, dentry);
 794                 }
 795                 iput(inode);
 796                 mutex_unlock(&EXFAT_SB(sb)->s_lock);
 797                 return alias;
 798         }
 799         dput(alias);
 800 out:
 801         mutex_unlock(&EXFAT_SB(sb)->s_lock);
 802         if (!inode)
 803                 exfat_d_version_set(dentry, inode_query_iversion(dir));
 804
 805         return d_splice_alias(inode, dentry);
 806 unlock:
 807         mutex_unlock(&EXFAT_SB(sb)->s_lock);
 808         return ERR_PTR(err);
 809 }
 810
 811 /* remove an entry, BUT don't truncate */
 812 static int exfat_unlink(struct inode *dir, struct dentry *dentry)
 813 {
 814         struct exfat_chain cdir;
 815         struct exfat_dentry *ep;
 816         struct super_block *sb = dir->i_sb;
 817         struct inode *inode = dentry->d_inode;
 818         struct exfat_inode_info *ei = EXFAT_I(inode);
 819         struct buffer_head *bh;
 820         sector_t sector;
 821         int num_entries, entry, err = 0;
 822
 823         mutex_lock(&EXFAT_SB(sb)->s_lock);
 824         exfat_chain_dup(&cdir, &ei->dir);
 825         entry = ei->entry;
 826         if (ei->dir.dir == DIR_DELETED) {
 827                 exfat_msg(sb, KERN_ERR, "abnormal access to deleted dentry");
 828                 err = -ENOENT;
 829                 goto unlock;
 830         }
 831
 832         ep = exfat_get_dentry(sb, &cdir, entry, &bh, &sector);
 833         if (!ep) {
 834                 err = -EIO;
 835                 goto unlock;
 836         }
 837         num_entries = exfat_count_ext_entries(sb, &cdir, entry, ep);
 838         if (num_entries < 0) {
 839                 err = -EIO;
 840                 brelse(bh);
 841                 goto unlock;
 842         }
 843         num_entries++;
 844         brelse(bh);
 845
 846         exfat_set_vol_flags(sb, VOL_DIRTY);
 847         /* update the directory entry */
 848         if (exfat_remove_entries(dir, &cdir, entry, 0, num_entries)) {
 849                 err = -EIO;
 850                 goto unlock;
 851         }
 852
 853         /* This doesn't modify ei */
 854         ei->dir.dir = DIR_DELETED;
 855         exfat_set_vol_flags(sb, VOL_CLEAN);
 856
 857         inode_inc_iversion(dir);
 858         dir->i_mtime = dir->i_atime = current_time(dir);
 859         exfat_truncate_atime(&dir->i_atime);
 860         if (IS_DIRSYNC(dir))
 861                 exfat_sync_inode(dir);
 862         else
 863                 mark_inode_dirty(dir);
 864
 865         clear_nlink(inode);
 866         inode->i_mtime = inode->i_atime = current_time(inode);
 867         exfat_truncate_atime(&inode->i_atime);
 868         exfat_unhash_inode(inode);
 869         exfat_d_version_set(dentry, inode_query_iversion(dir));
 870 unlock:
 871         mutex_unlock(&EXFAT_SB(sb)->s_lock);
 872         return err;
 873 }
 874
 875 static int exfat_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
 876 {
 877         struct super_block *sb = dir->i_sb;
 878         struct inode *inode;
 879         struct exfat_dir_entry info;
 880         struct exfat_chain cdir;
 881         loff_t i_pos;
 882         int err;
 883
 884         mutex_lock(&EXFAT_SB(sb)->s_lock);
 885         exfat_set_vol_flags(sb, VOL_DIRTY);
 886         err = exfat_add_entry(dir, dentry->d_name.name, &cdir, TYPE_DIR,
 887                 &info);
 888         exfat_set_vol_flags(sb, VOL_CLEAN);
 889         if (err)
 890                 goto unlock;
 891
 892         inode_inc_iversion(dir);
 893         dir->i_ctime = dir->i_mtime = current_time(dir);
 894         if (IS_DIRSYNC(dir))
 895                 exfat_sync_inode(dir);
 896         else
 897                 mark_inode_dirty(dir);
 898         inc_nlink(dir);
 899
 900         i_pos = exfat_make_i_pos(&info);
 901         inode = exfat_build_inode(sb, &info, i_pos);
 902         if (IS_ERR(inode)) {
 903                 err = PTR_ERR(inode);
 904                 goto unlock;
 905         }
 906
 907         inode_inc_iversion(inode);
 908         inode->i_mtime = inode->i_atime = inode->i_ctime =
 909                 EXFAT_I(inode)->i_crtime = current_time(inode);
 910         exfat_truncate_atime(&inode->i_atime);
 911         /* timestamp is already written, so mark_inode_dirty() is unneeded. */
 912
 913         d_instantiate(dentry, inode);
 914
 915 unlock:
 916         mutex_unlock(&EXFAT_SB(sb)->s_lock);
 917         return err;
 918 }
 919
 920 static int exfat_check_dir_empty(struct super_block *sb,
 921                 struct exfat_chain *p_dir)
 922 {
 923         int i, dentries_per_clu;
 924         unsigned int type;
 925         struct exfat_chain clu;
 926         struct exfat_dentry *ep;
 927         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 928         struct buffer_head *bh;
 929
 930         dentries_per_clu = sbi->dentries_per_clu;
 931
 932         exfat_chain_dup(&clu, p_dir);
 933
 934         while (clu.dir != EXFAT_EOF_CLUSTER) {
 935                 for (i = 0; i < dentries_per_clu; i++) {
 936                         ep = exfat_get_dentry(sb, &clu, i, &bh, NULL);
 937                         if (!ep)
 938                                 return -EIO;
 939                         type = exfat_get_entry_type(ep);
 940                         brelse(bh);
 941                         if (type == TYPE_UNUSED)
 942                                 return 0;
 943
 944                         if (type != TYPE_FILE && type != TYPE_DIR)
 945                                 continue;
 946
 947                         return -ENOTEMPTY;
 948                 }
 949
 950                 if (clu.flags == ALLOC_NO_FAT_CHAIN) {
 951                         if (--clu.size > 0)
 952                                 clu.dir++;
 953                         else
 954                                 clu.dir = EXFAT_EOF_CLUSTER;
 955                 } else {
 956                         if (exfat_get_next_cluster(sb, &(clu.dir)))
 957                                 return -EIO;
 958                 }
 959         }
 960
 961         return 0;
 962 }
 963
 964 static int exfat_rmdir(struct inode *dir, struct dentry *dentry)
 965 {
 966         struct inode *inode = dentry->d_inode;
 967         struct exfat_dentry *ep;
 968         struct exfat_chain cdir, clu_to_free;
 969         struct super_block *sb = inode->i_sb;
 970         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 971         struct exfat_inode_info *ei = EXFAT_I(inode);
 972         struct buffer_head *bh;
 973         sector_t sector;
 974         int num_entries, entry, err;
 975
 976         mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock);
 977
 978         exfat_chain_dup(&cdir, &ei->dir);
 979         entry = ei->entry;
 980
 981         if (ei->dir.dir == DIR_DELETED) {
 982                 exfat_msg(sb, KERN_ERR, "abnormal access to deleted dentry");
 983                 err = -ENOENT;
 984                 goto unlock;
 985         }
 986
 987         exfat_set_vol_flags(sb, VOL_DIRTY);
 988         exfat_chain_set(&clu_to_free, ei->start_clu,
 989                 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(inode), sbi), ei->flags);
 990
 991         err = exfat_check_dir_empty(sb, &clu_to_free);
 992         if (err) {
 993                 if (err == -EIO)
 994                         exfat_msg(sb, KERN_ERR,
 995                                 "failed to exfat_check_dir_empty : err(%d)",
 996                                 err);
 997                 goto unlock;
 998         }
 999
1000         ep = exfat_get_dentry(sb, &cdir, entry, &bh, &sector);
1001         if (!ep) {
1002                 err = -EIO;
1003                 goto unlock;
1004         }
1005
1006         num_entries = exfat_count_ext_entries(sb, &cdir, entry, ep);
1007         if (num_entries < 0) {
1008                 err = -EIO;
1009                 brelse(bh);
1010                 goto unlock;
1011         }
1012         num_entries++;
1013         brelse(bh);
1014
1015         err = exfat_remove_entries(dir, &cdir, entry, 0, num_entries);
1016         if (err) {
1017                 exfat_msg(sb, KERN_ERR,
1018                                 "failed to exfat_remove_entries : err(%d)",
1019                                 err);
1020                 goto unlock;
1021         }
1022         ei->dir.dir = DIR_DELETED;
1023         exfat_set_vol_flags(sb, VOL_CLEAN);
1024
1025         inode_inc_iversion(dir);
1026         dir->i_mtime = dir->i_atime = current_time(dir);
1027         exfat_truncate_atime(&dir->i_atime);
1028         if (IS_DIRSYNC(dir))
1029                 exfat_sync_inode(dir);
1030         else
1031                 mark_inode_dirty(dir);
1032         drop_nlink(dir);
1033
1034         clear_nlink(inode);
1035         inode->i_mtime = inode->i_atime = current_time(inode);
1036         exfat_truncate_atime(&inode->i_atime);
1037         exfat_unhash_inode(inode);
1038         exfat_d_version_set(dentry, inode_query_iversion(dir));
1039 unlock:
1040         mutex_unlock(&EXFAT_SB(inode->i_sb)->s_lock);
1041         return err;
1042 }
1043
1044 static int exfat_rename_file(struct inode *inode, struct exfat_chain *p_dir,
1045                 int oldentry, struct exfat_uni_name *p_uniname,
1046                 struct exfat_inode_info *ei)
1047 {
1048         int ret, num_old_entries, num_new_entries;
1049         sector_t sector_old, sector_new;
1050         struct exfat_dentry *epold, *epnew;
1051         struct super_block *sb = inode->i_sb;
1052         struct buffer_head *new_bh, *old_bh;
1053         int sync = IS_DIRSYNC(inode);
1054
1055         epold = exfat_get_dentry(sb, p_dir, oldentry, &old_bh, &sector_old);
1056         if (!epold)
1057                 return -EIO;
1058
1059         num_old_entries = exfat_count_ext_entries(sb, p_dir, oldentry, epold);
1060         if (num_old_entries < 0)
1061                 return -EIO;
1062         num_old_entries++;
1063
1064         num_new_entries = exfat_calc_num_entries(p_uniname);
1065         if (num_new_entries < 0)
1066                 return num_new_entries;
1067
1068         if (num_old_entries < num_new_entries) {
1069                 int newentry;
1070
1071                 newentry =
1072                         exfat_find_empty_entry(inode, p_dir, num_new_entries);
1073                 if (newentry < 0)
1074                         return newentry; /* -EIO or -ENOSPC */
1075
1076                 epnew = exfat_get_dentry(sb, p_dir, newentry, &new_bh,
1077                         &sector_new);
1078                 if (!epnew)
1079                         return -EIO;
1080
1081                 memcpy(epnew, epold, DENTRY_SIZE);
1082                 if (exfat_get_entry_type(epnew) == TYPE_FILE) {
1083                         epnew->dentry.file.attr |= cpu_to_le16(ATTR_ARCHIVE);
1084                         ei->attr |= ATTR_ARCHIVE;
1085                 }
1086                 exfat_update_bh(sb, new_bh, sync);
1087                 brelse(old_bh);
1088                 brelse(new_bh);
1089
1090                 epold = exfat_get_dentry(sb, p_dir, oldentry + 1, &old_bh,
1091                         &sector_old);
1092                 epnew = exfat_get_dentry(sb, p_dir, newentry + 1, &new_bh,
1093                         &sector_new);
1094                 if (!epold || !epnew)
1095                         return -EIO;
1096
1097                 memcpy(epnew, epold, DENTRY_SIZE);
1098                 exfat_update_bh(sb, new_bh, sync);
1099                 brelse(old_bh);
1100                 brelse(new_bh);
1101
1102                 ret = exfat_init_ext_entry(inode, p_dir, newentry,
1103                         num_new_entries, p_uniname);
1104                 if (ret)
1105                         return ret;
1106
1107                 exfat_remove_entries(inode, p_dir, oldentry, 0,
1108                         num_old_entries);
1109                 ei->entry = newentry;
1110         } else {
1111                 if (exfat_get_entry_type(epold) == TYPE_FILE) {
1112                         epold->dentry.file.attr |= cpu_to_le16(ATTR_ARCHIVE);
1113                         ei->attr |= ATTR_ARCHIVE;
1114                 }
1115                 exfat_update_bh(sb, old_bh, sync);
1116                 brelse(old_bh);
1117                 ret = exfat_init_ext_entry(inode, p_dir, oldentry,
1118                         num_new_entries, p_uniname);
1119                 if (ret)
1120                         return ret;
1121
1122                 exfat_remove_entries(inode, p_dir, oldentry, num_new_entries,
1123                         num_old_entries);
1124         }
1125         return 0;
1126 }
1127
1128 static int exfat_move_file(struct inode *inode, struct exfat_chain *p_olddir,
1129                 int oldentry, struct exfat_chain *p_newdir,
1130                 struct exfat_uni_name *p_uniname, struct exfat_inode_info *ei)
1131 {
1132         int ret, newentry, num_new_entries, num_old_entries;
1133         sector_t sector_mov, sector_new;
1134         struct exfat_dentry *epmov, *epnew;
1135         struct super_block *sb = inode->i_sb;
1136         struct buffer_head *mov_bh, *new_bh;
1137
1138         epmov = exfat_get_dentry(sb, p_olddir, oldentry, &mov_bh, &sector_mov);
1139         if (!epmov)
1140                 return -EIO;
1141
1142         /* check if the source and target directory is the same */
1143         if (exfat_get_entry_type(epmov) == TYPE_DIR &&
1144             le32_to_cpu(epmov->dentry.stream.start_clu) == p_newdir->dir)
1145                 return -EINVAL;
1146
1147         num_old_entries = exfat_count_ext_entries(sb, p_olddir, oldentry,
1148                 epmov);
1149         if (num_old_entries < 0)
1150                 return -EIO;
1151         num_old_entries++;
1152
1153         num_new_entries = exfat_calc_num_entries(p_uniname);
1154         if (num_new_entries < 0)
1155                 return num_new_entries;
1156
1157         newentry = exfat_find_empty_entry(inode, p_newdir, num_new_entries);
1158         if (newentry < 0)
1159                 return newentry; /* -EIO or -ENOSPC */
1160
1161         epnew = exfat_get_dentry(sb, p_newdir, newentry, &new_bh, &sector_new);
1162         if (!epnew)
1163                 return -EIO;
1164
1165         memcpy(epnew, epmov, DENTRY_SIZE);
1166         if (exfat_get_entry_type(epnew) == TYPE_FILE) {
1167                 epnew->dentry.file.attr |= cpu_to_le16(ATTR_ARCHIVE);
1168                 ei->attr |= ATTR_ARCHIVE;
1169         }
1170         exfat_update_bh(sb, new_bh, IS_DIRSYNC(inode));
1171         brelse(mov_bh);
1172         brelse(new_bh);
1173
1174         epmov = exfat_get_dentry(sb, p_olddir, oldentry + 1, &mov_bh,
1175                 &sector_mov);
1176         epnew = exfat_get_dentry(sb, p_newdir, newentry + 1, &new_bh,
1177                 &sector_new);
1178         if (!epmov || !epnew)
1179                 return -EIO;
1180
1181         memcpy(epnew, epmov, DENTRY_SIZE);
1182         exfat_update_bh(sb, new_bh, IS_DIRSYNC(inode));
1183         brelse(mov_bh);
1184         brelse(new_bh);
1185
1186         ret = exfat_init_ext_entry(inode, p_newdir, newentry, num_new_entries,
1187                 p_uniname);
1188         if (ret)
1189                 return ret;
1190
1191         exfat_remove_entries(inode, p_olddir, oldentry, 0, num_old_entries);
1192
1193         exfat_chain_set(&ei->dir, p_newdir->dir, p_newdir->size,
1194                 p_newdir->flags);
1195
1196         ei->entry = newentry;
1197         return 0;
1198 }
1199
1200 static void exfat_update_parent_info(struct exfat_inode_info *ei,
1201                 struct inode *parent_inode)
1202 {
1203         struct exfat_sb_info *sbi = EXFAT_SB(parent_inode->i_sb);
1204         struct exfat_inode_info *parent_ei = EXFAT_I(parent_inode);
1205         loff_t parent_isize = i_size_read(parent_inode);
1206
1207         /*
1208          * the problem that struct exfat_inode_info caches wrong parent info.
1209          *
1210          * because of flag-mismatch of ei->dir,
1211          * there is abnormal traversing cluster chain.
1212          */
1213         if (unlikely(parent_ei->flags != ei->dir.flags ||
1214                      parent_isize != EXFAT_CLU_TO_B(ei->dir.size, sbi) ||
1215                      parent_ei->start_clu != ei->dir.dir)) {
1216                 exfat_chain_set(&ei->dir, parent_ei->start_clu,
1217                         EXFAT_B_TO_CLU_ROUND_UP(parent_isize, sbi),
1218                         parent_ei->flags);
1219         }
1220 }
1221
1222 /* rename or move a old file into a new file */
1223 static int __exfat_rename(struct inode *old_parent_inode,
1224                 struct exfat_inode_info *ei, struct inode *new_parent_inode,
1225                 struct dentry *new_dentry)
1226 {
1227         int ret;
1228         int dentry;
1229         struct exfat_chain olddir, newdir;
1230         struct exfat_chain *p_dir = NULL;
1231         struct exfat_uni_name uni_name;
1232         struct exfat_dentry *ep;
1233         struct super_block *sb = old_parent_inode->i_sb;
1234         struct exfat_sb_info *sbi = EXFAT_SB(sb);
1235         const unsigned char *new_path = new_dentry->d_name.name;
1236         struct inode *new_inode = new_dentry->d_inode;
1237         int num_entries;
1238         struct exfat_inode_info *new_ei = NULL;
1239         unsigned int new_entry_type = TYPE_UNUSED;
1240         int new_entry = 0;
1241         struct buffer_head *old_bh, *new_bh = NULL;
1242
1243         /* check the validity of pointer parameters */
1244         if (new_path == NULL || strlen(new_path) == 0)
1245                 return -EINVAL;
1246
1247         if (ei->dir.dir == DIR_DELETED) {
1248                 exfat_msg(sb, KERN_ERR,
1249                                 "abnormal access to deleted source dentry");
1250                 return -ENOENT;
1251         }
1252
1253         exfat_update_parent_info(ei, old_parent_inode);
1254
1255         exfat_chain_dup(&olddir, &ei->dir);
1256         dentry = ei->entry;
1257
1258         ep = exfat_get_dentry(sb, &olddir, dentry, &old_bh, NULL);
1259         if (!ep) {
1260                 ret = -EIO;
1261                 goto out;
1262         }
1263         brelse(old_bh);
1264
1265         /* check whether new dir is existing directory and empty */
1266         if (new_inode) {
1267                 ret = -EIO;
1268                 new_ei = EXFAT_I(new_inode);
1269
1270                 if (new_ei->dir.dir == DIR_DELETED) {
1271                         exfat_msg(sb, KERN_ERR,
1272                                 "abnormal access to deleted target dentry");
1273                         goto out;
1274                 }
1275
1276                 exfat_update_parent_info(new_ei, new_parent_inode);
1277
1278                 p_dir = &(new_ei->dir);
1279                 new_entry = new_ei->entry;
1280                 ep = exfat_get_dentry(sb, p_dir, new_entry, &new_bh, NULL);
1281                 if (!ep)
1282                         goto out;
1283
1284                 new_entry_type = exfat_get_entry_type(ep);
1285                 brelse(new_bh);
1286
1287                 /* if new_inode exists, update ei */
1288                 if (new_entry_type == TYPE_DIR) {
1289                         struct exfat_chain new_clu;
1290
1291                         new_clu.dir = new_ei->start_clu;
1292                         new_clu.size =
1293                                 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode),
1294                                 sbi);
1295                         new_clu.flags = new_ei->flags;
1296
1297                         ret = exfat_check_dir_empty(sb, &new_clu);
1298                         if (ret)
1299                                 goto out;
1300                 }
1301         }
1302
1303         /* check the validity of directory name in the given new pathname */
1304         ret = exfat_resolve_path(new_parent_inode, new_path, &newdir,
1305                         &uni_name);
1306         if (ret)
1307                 goto out;
1308
1309         exfat_set_vol_flags(sb, VOL_DIRTY);
1310
1311         if (olddir.dir == newdir.dir)
1312                 ret = exfat_rename_file(new_parent_inode, &olddir, dentry,
1313                                 &uni_name, ei);
1314         else
1315                 ret = exfat_move_file(new_parent_inode, &olddir, dentry,
1316                                 &newdir, &uni_name, ei);
1317
1318         if (!ret && new_inode) {
1319                 /* delete entries of new_dir */
1320                 ep = exfat_get_dentry(sb, p_dir, new_entry, &new_bh, NULL);
1321                 if (!ep) {
1322                         ret = -EIO;
1323                         goto del_out;
1324                 }
1325
1326                 num_entries = exfat_count_ext_entries(sb, p_dir, new_entry, ep);
1327                 if (num_entries < 0) {
1328                         ret = -EIO;
1329                         goto del_out;
1330                 }
1331                 brelse(new_bh);
1332
1333                 if (exfat_remove_entries(new_inode, p_dir, new_entry, 0,
1334                                 num_entries + 1)) {
1335                         ret = -EIO;
1336                         goto del_out;
1337                 }
1338
1339                 /* Free the clusters if new_inode is a dir(as if exfat_rmdir) */
1340                 if (new_entry_type == TYPE_DIR) {
1341                         /* new_ei, new_clu_to_free */
1342                         struct exfat_chain new_clu_to_free;
1343
1344                         exfat_chain_set(&new_clu_to_free, new_ei->start_clu,
1345                                 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode),
1346                                 sbi), new_ei->flags);
1347
1348                         if (exfat_free_cluster(new_inode, &new_clu_to_free)) {
1349                                 /* just set I/O error only */
1350                                 ret = -EIO;
1351                         }
1352
1353                         i_size_write(new_inode, 0);
1354                         new_ei->start_clu = EXFAT_EOF_CLUSTER;
1355                         new_ei->flags = ALLOC_NO_FAT_CHAIN;
1356                 }
1357 del_out:
1358                 /* Update new_inode ei
1359                  * Prevent syncing removed new_inode
1360                  * (new_ei is already initialized above code ("if (new_inode)")
1361                  */
1362                 new_ei->dir.dir = DIR_DELETED;
1363         }
1364         exfat_set_vol_flags(sb, VOL_CLEAN);
1365 out:
1366         return ret;
1367 }
1368
1369 static int exfat_rename(struct inode *old_dir, struct dentry *old_dentry,
1370                 struct inode *new_dir, struct dentry *new_dentry,
1371                 unsigned int flags)
1372 {
1373         struct inode *old_inode, *new_inode;
1374         struct super_block *sb = old_dir->i_sb;
1375         loff_t i_pos;
1376         int err;
1377
1378         /*
1379          * The VFS already checks for existence, so for local filesystems
1380          * the RENAME_NOREPLACE implementation is equivalent to plain rename.
1381          * Don't support any other flags
1382          */
1383         if (flags & ~RENAME_NOREPLACE)
1384                 return -EINVAL;
1385
1386         mutex_lock(&EXFAT_SB(sb)->s_lock);
1387         old_inode = old_dentry->d_inode;
1388         new_inode = new_dentry->d_inode;
1389
1390         err = __exfat_rename(old_dir, EXFAT_I(old_inode), new_dir, new_dentry);
1391         if (err)
1392                 goto unlock;
1393
1394         inode_inc_iversion(new_dir);
1395         new_dir->i_ctime = new_dir->i_mtime = new_dir->i_atime =
1396                 EXFAT_I(new_dir)->i_crtime = current_time(new_dir);
1397         exfat_truncate_atime(&new_dir->i_atime);
1398         if (IS_DIRSYNC(new_dir))
1399                 exfat_sync_inode(new_dir);
1400         else
1401                 mark_inode_dirty(new_dir);
1402
1403         i_pos = ((loff_t)EXFAT_I(old_inode)->dir.dir << 32) |
1404                 (EXFAT_I(old_inode)->entry & 0xffffffff);
1405         exfat_unhash_inode(old_inode);
1406         exfat_hash_inode(old_inode, i_pos);
1407         if (IS_DIRSYNC(new_dir))
1408                 exfat_sync_inode(old_inode);
1409         else
1410                 mark_inode_dirty(old_inode);
1411
1412         if (S_ISDIR(old_inode->i_mode) && old_dir != new_dir) {
1413                 drop_nlink(old_dir);
1414                 if (!new_inode)
1415                         inc_nlink(new_dir);
1416         }
1417
1418         inode_inc_iversion(old_dir);
1419         old_dir->i_ctime = old_dir->i_mtime = current_time(old_dir);
1420         if (IS_DIRSYNC(old_dir))
1421                 exfat_sync_inode(old_dir);
1422         else
1423                 mark_inode_dirty(old_dir);
1424
1425         if (new_inode) {
1426                 exfat_unhash_inode(new_inode);
1427
1428                 /* skip drop_nlink if new_inode already has been dropped */
1429                 if (new_inode->i_nlink) {
1430                         drop_nlink(new_inode);
1431                         if (S_ISDIR(new_inode->i_mode))
1432                                 drop_nlink(new_inode);
1433                 } else {
1434                         exfat_msg(sb, KERN_WARNING,
1435                                         "abnormal access to an inode dropped");
1436                         WARN_ON(new_inode->i_nlink == 0);
1437                 }
1438                 new_inode->i_ctime = EXFAT_I(new_inode)->i_crtime =
1439                         current_time(new_inode);
1440         }
1441
1442 unlock:
1443         mutex_unlock(&EXFAT_SB(sb)->s_lock);
1444         return err;
1445 }
1446
1447 const struct inode_operations exfat_dir_inode_operations = {
1448         .create         = exfat_create,
1449         .lookup         = exfat_lookup,
1450         .unlink         = exfat_unlink,
1451         .mkdir          = exfat_mkdir,
1452         .rmdir          = exfat_rmdir,
1453         .rename         = exfat_rename,
1454         .setattr        = exfat_setattr,
1455         .getattr        = exfat_getattr,
1456 };