fs/exfat/namei.c

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