fs/exfat/namei.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright (C) 2012-2013 Samsung Electronics Co., Ltd.
   4  */
   5
   6 #include <linux/iversion.h>
   7 #include <linux/namei.h>
   8 #include <linux/slab.h>
   9 #include <linux/buffer_head.h>
  10 #include <linux/nls.h>
  11
  12 #include "exfat_raw.h"
  13 #include "exfat_fs.h"
  14
  15 static inline unsigned long exfat_d_version(struct dentry *dentry)
  16 {
  17         return (unsigned long) dentry->d_fsdata;
  18 }
  19
  20 static inline void exfat_d_version_set(struct dentry *dentry,
  21                 unsigned long version)
  22 {
  23         dentry->d_fsdata = (void *) version;
  24 }
  25
  26 /*
  27  * If new entry was created in the parent, it could create the 8.3 alias (the
  28  * shortname of logname).  So, the parent may have the negative-dentry which
  29  * matches the created 8.3 alias.
  30  *
  31  * If it happened, the negative dentry isn't actually negative anymore.  So,
  32  * drop it.
  33  */
  34 static int exfat_d_revalidate(struct dentry *dentry, unsigned int flags)
  35 {
  36         int ret;
  37
  38         if (flags & LOOKUP_RCU)
  39                 return -ECHILD;
  40
  41         /*
  42          * This is not negative dentry. Always valid.
  43          *
  44          * Note, rename() to existing directory entry will have ->d_inode, and
  45          * will use existing name which isn't specified name by user.
  46          *
  47          * We may be able to drop this positive dentry here. But dropping
  48          * positive dentry isn't good idea. So it's unsupported like
  49          * rename("filename", "FILENAME") for now.
  50          */
  51         if (d_really_is_positive(dentry))
  52                 return 1;
  53
  54         /*
  55          * Drop the negative dentry, in order to make sure to use the case
  56          * sensitive name which is specified by user if this is for creation.
  57          */
  58         if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))
  59                 return 0;
  60
  61         spin_lock(&dentry->d_lock);
  62         ret = inode_eq_iversion(d_inode(dentry->d_parent),
  63                         exfat_d_version(dentry));
  64         spin_unlock(&dentry->d_lock);
  65         return ret;
  66 }
  67
  68 /* returns the length of a struct qstr, ignoring trailing dots */
  69 static unsigned int exfat_striptail_len(unsigned int len, const char *name)
  70 {
  71         while (len && name[len - 1] == '.')
  72                 len--;
  73         return len;
  74 }
  75
  76 /*
  77  * Compute the hash for the exfat name corresponding to the dentry.  If the name
  78  * is invalid, we leave the hash code unchanged so that the existing dentry can
  79  * be used. The exfat fs routines will return ENOENT or EINVAL as appropriate.
  80  */
  81 static int exfat_d_hash(const struct dentry *dentry, struct qstr *qstr)
  82 {
  83         struct super_block *sb = dentry->d_sb;
  84         struct nls_table *t = EXFAT_SB(sb)->nls_io;
  85         const unsigned char *name = qstr->name;
  86         unsigned int len = exfat_striptail_len(qstr->len, qstr->name);
  87         unsigned long hash = init_name_hash(dentry);
  88         int i, charlen;
  89         wchar_t c;
  90
  91         for (i = 0; i < len; i += charlen) {
  92                 charlen = t->char2uni(&name[i], len - i, &c);
  93                 if (charlen < 0)
  94                         return charlen;
  95                 hash = partial_name_hash(exfat_toupper(sb, c), hash);
  96         }
  97
  98         qstr->hash = end_name_hash(hash);
  99         return 0;
 100 }
 101
 102 static int exfat_d_cmp(const struct dentry *dentry, unsigned int len,
 103                 const char *str, const struct qstr *name)
 104 {
 105         struct super_block *sb = dentry->d_sb;
 106         struct nls_table *t = EXFAT_SB(sb)->nls_io;
 107         unsigned int alen = exfat_striptail_len(name->len, name->name);
 108         unsigned int blen = exfat_striptail_len(len, str);
 109         wchar_t c1, c2;
 110         int charlen, i;
 111
 112         if (alen != blen)
 113                 return 1;
 114
 115         for (i = 0; i < len; i += charlen) {
 116                 charlen = t->char2uni(&name->name[i], alen - i, &c1);
 117                 if (charlen < 0)
 118                         return 1;
 119                 if (charlen != t->char2uni(&str[i], blen - i, &c2))
 120                         return 1;
 121
 122                 if (exfat_toupper(sb, c1) != exfat_toupper(sb, c2))
 123                         return 1;
 124         }
 125
 126         return 0;
 127 }
 128
 129 const struct dentry_operations exfat_dentry_ops = {
 130         .d_revalidate   = exfat_d_revalidate,
 131         .d_hash         = exfat_d_hash,
 132         .d_compare      = exfat_d_cmp,
 133 };
 134
 135 static int exfat_utf8_d_hash(const struct dentry *dentry, struct qstr *qstr)
 136 {
 137         struct super_block *sb = dentry->d_sb;
 138         const unsigned char *name = qstr->name;
 139         unsigned int len = exfat_striptail_len(qstr->len, qstr->name);
 140         unsigned long hash = init_name_hash(dentry);
 141         int i, charlen;
 142         unicode_t u;
 143
 144         for (i = 0; i < len; i += charlen) {
 145                 charlen = utf8_to_utf32(&name[i], len - i, &u);
 146                 if (charlen < 0)
 147                         return charlen;
 148
 149                 /*
 150                  * exfat_toupper() works only for code points up to the U+FFFF.
 151                  */
 152                 hash = partial_name_hash(u <= 0xFFFF ? exfat_toupper(sb, u) : u,
 153                                          hash);
 154         }
 155
 156         qstr->hash = end_name_hash(hash);
 157         return 0;
 158 }
 159
 160 static int exfat_utf8_d_cmp(const struct dentry *dentry, unsigned int len,
 161                 const char *str, const struct qstr *name)
 162 {
 163         struct super_block *sb = dentry->d_sb;
 164         unsigned int alen = exfat_striptail_len(name->len, name->name);
 165         unsigned int blen = exfat_striptail_len(len, str);
 166         unicode_t u_a, u_b;
 167         int charlen, i;
 168
 169         if (alen != blen)
 170                 return 1;
 171
 172         for (i = 0; i < alen; i += charlen) {
 173                 charlen = utf8_to_utf32(&name->name[i], alen - i, &u_a);
 174                 if (charlen < 0)
 175                         return 1;
 176                 if (charlen != utf8_to_utf32(&str[i], blen - i, &u_b))
 177                         return 1;
 178
 179                 if (u_a <= 0xFFFF && u_b <= 0xFFFF) {
 180                         if (exfat_toupper(sb, u_a) != exfat_toupper(sb, u_b))
 181                                 return 1;
 182                 } else {
 183                         if (u_a != u_b)
 184                                 return 1;
 185                 }
 186         }
 187
 188         return 0;
 189 }
 190
 191 const struct dentry_operations exfat_utf8_dentry_ops = {
 192         .d_revalidate   = exfat_d_revalidate,
 193         .d_hash         = exfat_utf8_d_hash,
 194         .d_compare      = exfat_utf8_d_cmp,
 195 };
 196
 197 /* used only in search empty_slot() */
 198 #define CNT_UNUSED_NOHIT        (-1)
 199 #define CNT_UNUSED_HIT          (-2)
 200 /* search EMPTY CONTINUOUS "num_entries" entries */
 201 static int exfat_search_empty_slot(struct super_block *sb,
 202                 struct exfat_hint_femp *hint_femp, struct exfat_chain *p_dir,
 203                 int num_entries)
 204 {
 205         int i, dentry, num_empty = 0;
 206         int dentries_per_clu;
 207         unsigned int type;
 208         struct exfat_chain clu;
 209         struct exfat_dentry *ep;
 210         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 211         struct buffer_head *bh;
 212
 213         dentries_per_clu = sbi->dentries_per_clu;
 214
 215         if (hint_femp->eidx != EXFAT_HINT_NONE) {
 216                 dentry = hint_femp->eidx;
 217                 if (num_entries <= hint_femp->count) {
 218                         hint_femp->eidx = EXFAT_HINT_NONE;
 219                         return dentry;
 220                 }
 221
 222                 exfat_chain_dup(&clu, &hint_femp->cur);
 223         } else {
 224                 exfat_chain_dup(&clu, p_dir);
 225                 dentry = 0;
 226         }
 227
 228         while (clu.dir != EXFAT_EOF_CLUSTER) {
 229                 i = dentry & (dentries_per_clu - 1);
 230
 231                 for (; i < dentries_per_clu; i++, dentry++) {
 232                         ep = exfat_get_dentry(sb, &clu, i, &bh);
 233                         if (!ep)
 234                                 return -EIO;
 235                         type = exfat_get_entry_type(ep);
 236                         brelse(bh);
 237
 238                         if (type == TYPE_UNUSED || type == TYPE_DELETED) {
 239                                 num_empty++;
 240                                 if (hint_femp->eidx == EXFAT_HINT_NONE) {
 241                                         hint_femp->eidx = dentry;
 242                                         hint_femp->count = CNT_UNUSED_NOHIT;
 243                                         exfat_chain_set(&hint_femp->cur,
 244                                                 clu.dir, clu.size, clu.flags);
 245                                 }
 246
 247                                 if (type == TYPE_UNUSED &&
 248                                     hint_femp->count != CNT_UNUSED_HIT)
 249                                         hint_femp->count = CNT_UNUSED_HIT;
 250                         } else {
 251                                 if (hint_femp->eidx != EXFAT_HINT_NONE &&
 252                                     hint_femp->count == CNT_UNUSED_HIT) {
 253                                         /* unused empty group means
 254                                          * an empty group which includes
 255                                          * unused dentry
 256                                          */
 257                                         exfat_fs_error(sb,
 258                                                 "found bogus dentry(%d) beyond unused empty group(%d) (start_clu : %u, cur_clu : %u)",
 259                                                 dentry, hint_femp->eidx,
 260                                                 p_dir->dir, clu.dir);
 261                                         return -EIO;
 262                                 }
 263
 264                                 num_empty = 0;
 265                                 hint_femp->eidx = EXFAT_HINT_NONE;
 266                         }
 267
 268                         if (num_empty >= num_entries) {
 269                                 /* found and invalidate hint_femp */
 270                                 hint_femp->eidx = EXFAT_HINT_NONE;
 271                                 return (dentry - (num_entries - 1));
 272                         }
 273                 }
 274
 275                 if (clu.flags == ALLOC_NO_FAT_CHAIN) {
 276                         if (--clu.size > 0)
 277                                 clu.dir++;
 278                         else
 279                                 clu.dir = EXFAT_EOF_CLUSTER;
 280                 } else {
 281                         if (exfat_get_next_cluster(sb, &clu.dir))
 282                                 return -EIO;
 283                 }
 284         }
 285
 286         return -ENOSPC;
 287 }
 288
 289 static int exfat_check_max_dentries(struct inode *inode)
 290 {
 291         if (EXFAT_B_TO_DEN(i_size_read(inode)) >= MAX_EXFAT_DENTRIES) {
 292                 /*
 293                  * exFAT spec allows a dir to grow up to 8388608(256MB)
 294                  * dentries
 295                  */
 296                 return -ENOSPC;
 297         }
 298         return 0;
 299 }
 300
 301 /* find empty directory entry.
 302  * if there isn't any empty slot, expand cluster chain.
 303  */
 304 static int exfat_find_empty_entry(struct inode *inode,
 305                 struct exfat_chain *p_dir, int num_entries)
 306 {
 307         int dentry;
 308         unsigned int ret, last_clu;
 309         loff_t size = 0;
 310         struct exfat_chain clu;
 311         struct exfat_dentry *ep = NULL;
 312         struct super_block *sb = inode->i_sb;
 313         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 314         struct exfat_inode_info *ei = EXFAT_I(inode);
 315         struct exfat_hint_femp hint_femp;
 316
 317         hint_femp.eidx = EXFAT_HINT_NONE;
 318
 319         if (ei->hint_femp.eidx != EXFAT_HINT_NONE) {
 320                 hint_femp = ei->hint_femp;
 321                 ei->hint_femp.eidx = EXFAT_HINT_NONE;
 322         }
 323
 324         while ((dentry = exfat_search_empty_slot(sb, &hint_femp, p_dir,
 325                                         num_entries)) < 0) {
 326                 if (dentry == -EIO)
 327                         break;
 328
 329                 if (exfat_check_max_dentries(inode))
 330                         return -ENOSPC;
 331
 332                 /* we trust p_dir->size regardless of FAT type */
 333                 if (exfat_find_last_cluster(sb, p_dir, &last_clu))
 334                         return -EIO;
 335
 336                 /*
 337                  * Allocate new cluster to this directory
 338                  */
 339                 exfat_chain_set(&clu, last_clu + 1, 0, p_dir->flags);
 340
 341                 /* allocate a cluster */
 342                 ret = exfat_alloc_cluster(inode, 1, &clu, IS_DIRSYNC(inode));
 343                 if (ret)
 344                         return ret;
 345
 346                 if (exfat_zeroed_cluster(inode, clu.dir))
 347                         return -EIO;
 348
 349                 /* append to the FAT chain */
 350                 if (clu.flags != p_dir->flags) {
 351                         /* no-fat-chain bit is disabled,
 352                          * so fat-chain should be synced with alloc-bitmap
 353                          */
 354                         exfat_chain_cont_cluster(sb, p_dir->dir, p_dir->size);
 355                         p_dir->flags = ALLOC_FAT_CHAIN;
 356                         hint_femp.cur.flags = ALLOC_FAT_CHAIN;
 357                 }
 358
 359                 if (clu.flags == ALLOC_FAT_CHAIN)
 360                         if (exfat_ent_set(sb, last_clu, clu.dir))
 361                                 return -EIO;
 362
 363                 if (hint_femp.eidx == EXFAT_HINT_NONE) {
 364                         /* the special case that new dentry
 365                          * should be allocated from the start of new cluster
 366                          */
 367                         hint_femp.eidx = EXFAT_B_TO_DEN_IDX(p_dir->size, sbi);
 368                         hint_femp.count = sbi->dentries_per_clu;
 369
 370                         exfat_chain_set(&hint_femp.cur, clu.dir, 0, clu.flags);
 371                 }
 372                 hint_femp.cur.size++;
 373                 p_dir->size++;
 374                 size = EXFAT_CLU_TO_B(p_dir->size, sbi);
 375
 376                 /* update the directory entry */
 377                 if (p_dir->dir != sbi->root_dir) {
 378                         struct buffer_head *bh;
 379
 380                         ep = exfat_get_dentry(sb,
 381                                 &(ei->dir), ei->entry + 1, &bh);
 382                         if (!ep)
 383                                 return -EIO;
 384
 385                         ep->dentry.stream.valid_size = cpu_to_le64(size);
 386                         ep->dentry.stream.size = ep->dentry.stream.valid_size;
 387                         ep->dentry.stream.flags = p_dir->flags;
 388                         exfat_update_bh(bh, IS_DIRSYNC(inode));
 389                         brelse(bh);
 390                         if (exfat_update_dir_chksum(inode, &(ei->dir),
 391                             ei->entry))
 392                                 return -EIO;
 393                 }
 394
 395                 /* directory inode should be updated in here */
 396                 i_size_write(inode, size);
 397                 ei->i_size_ondisk += sbi->cluster_size;
 398                 ei->i_size_aligned += sbi->cluster_size;
 399                 ei->flags = p_dir->flags;
 400                 inode->i_blocks += 1 << sbi->sect_per_clus_bits;
 401         }
 402
 403         return dentry;
 404 }
 405
 406 /*
 407  * Name Resolution Functions :
 408  * Zero if it was successful; otherwise nonzero.
 409  */
 410 static int __exfat_resolve_path(struct inode *inode, const unsigned char *path,
 411                 struct exfat_chain *p_dir, struct exfat_uni_name *p_uniname,
 412                 int lookup)
 413 {
 414         int namelen;
 415         int lossy = NLS_NAME_NO_LOSSY;
 416         struct super_block *sb = inode->i_sb;
 417         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 418         struct exfat_inode_info *ei = EXFAT_I(inode);
 419
 420         /* strip all trailing periods */
 421         namelen = exfat_striptail_len(strlen(path), path);
 422         if (!namelen)
 423                 return -ENOENT;
 424
 425         if (strlen(path) > (MAX_NAME_LENGTH * MAX_CHARSET_SIZE))
 426                 return -ENAMETOOLONG;
 427
 428         /*
 429          * strip all leading spaces :
 430          * "MS windows 7" supports leading spaces.
 431          * So we should skip this preprocessing for compatibility.
 432          */
 433
 434         /* file name conversion :
 435          * If lookup case, we allow bad-name for compatibility.
 436          */
 437         namelen = exfat_nls_to_utf16(sb, path, namelen, p_uniname,
 438                         &lossy);
 439         if (namelen < 0)
 440                 return namelen; /* return error value */
 441
 442         if ((lossy && !lookup) || !namelen)
 443                 return -EINVAL;
 444
 445         exfat_chain_set(p_dir, ei->start_clu,
 446                 EXFAT_B_TO_CLU(i_size_read(inode), sbi), ei->flags);
 447
 448         return 0;
 449 }
 450
 451 static inline int exfat_resolve_path(struct inode *inode,
 452                 const unsigned char *path, struct exfat_chain *dir,
 453                 struct exfat_uni_name *uni)
 454 {
 455         return __exfat_resolve_path(inode, path, dir, uni, 0);
 456 }
 457
 458 static inline int exfat_resolve_path_for_lookup(struct inode *inode,
 459                 const unsigned char *path, struct exfat_chain *dir,
 460                 struct exfat_uni_name *uni)
 461 {
 462         return __exfat_resolve_path(inode, path, dir, uni, 1);
 463 }
 464
 465 static inline loff_t exfat_make_i_pos(struct exfat_dir_entry *info)
 466 {
 467         return ((loff_t) info->dir.dir << 32) | (info->entry & 0xffffffff);
 468 }
 469
 470 static int exfat_add_entry(struct inode *inode, const char *path,
 471                 struct exfat_chain *p_dir, unsigned int type,
 472                 struct exfat_dir_entry *info)
 473 {
 474         int ret, dentry, num_entries;
 475         struct super_block *sb = inode->i_sb;
 476         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 477         struct exfat_uni_name uniname;
 478         struct exfat_chain clu;
 479         int clu_size = 0;
 480         unsigned int start_clu = EXFAT_FREE_CLUSTER;
 481
 482         ret = exfat_resolve_path(inode, path, p_dir, &uniname);
 483         if (ret)
 484                 goto out;
 485
 486         num_entries = exfat_calc_num_entries(&uniname);
 487         if (num_entries < 0) {
 488                 ret = num_entries;
 489                 goto out;
 490         }
 491
 492         /* exfat_find_empty_entry must be called before alloc_cluster() */
 493         dentry = exfat_find_empty_entry(inode, p_dir, num_entries);
 494         if (dentry < 0) {
 495                 ret = dentry; /* -EIO or -ENOSPC */
 496                 goto out;
 497         }
 498
 499         if (type == TYPE_DIR) {
 500                 ret = exfat_alloc_new_dir(inode, &clu);
 501                 if (ret)
 502                         goto out;
 503                 start_clu = clu.dir;
 504                 clu_size = sbi->cluster_size;
 505         }
 506
 507         /* update the directory entry */
 508         /* fill the dos name directory entry information of the created file.
 509          * the first cluster is not determined yet. (0)
 510          */
 511         ret = exfat_init_dir_entry(inode, p_dir, dentry, type,
 512                 start_clu, clu_size);
 513         if (ret)
 514                 goto out;
 515
 516         ret = exfat_init_ext_entry(inode, p_dir, dentry, num_entries, &uniname);
 517         if (ret)
 518                 goto out;
 519
 520         info->dir = *p_dir;
 521         info->entry = dentry;
 522         info->flags = ALLOC_NO_FAT_CHAIN;
 523         info->type = type;
 524
 525         if (type == TYPE_FILE) {
 526                 info->attr = ATTR_ARCHIVE;
 527                 info->start_clu = EXFAT_EOF_CLUSTER;
 528                 info->size = 0;
 529                 info->num_subdirs = 0;
 530         } else {
 531                 info->attr = ATTR_SUBDIR;
 532                 info->start_clu = start_clu;
 533                 info->size = clu_size;
 534                 info->num_subdirs = EXFAT_MIN_SUBDIR;
 535         }
 536         memset(&info->crtime, 0, sizeof(info->crtime));
 537         memset(&info->mtime, 0, sizeof(info->mtime));
 538         memset(&info->atime, 0, sizeof(info->atime));
 539 out:
 540         return ret;
 541 }
 542
 543 static int exfat_create(struct user_namespace *mnt_userns, struct inode *dir,
 544                         struct dentry *dentry, umode_t mode, bool excl)
 545 {
 546         struct super_block *sb = dir->i_sb;
 547         struct inode *inode;
 548         struct exfat_chain cdir;
 549         struct exfat_dir_entry info;
 550         loff_t i_pos;
 551         int err;
 552
 553         mutex_lock(&EXFAT_SB(sb)->s_lock);
 554         exfat_set_volume_dirty(sb);
 555         err = exfat_add_entry(dir, dentry->d_name.name, &cdir, TYPE_FILE,
 556                 &info);
 557         exfat_clear_volume_dirty(sb);
 558         if (err)
 559                 goto unlock;
 560
 561         inode_inc_iversion(dir);
 562         dir->i_ctime = dir->i_mtime = current_time(dir);
 563         if (IS_DIRSYNC(dir))
 564                 exfat_sync_inode(dir);
 565         else
 566                 mark_inode_dirty(dir);
 567
 568         i_pos = exfat_make_i_pos(&info);
 569         inode = exfat_build_inode(sb, &info, i_pos);
 570         err = PTR_ERR_OR_ZERO(inode);
 571         if (err)
 572                 goto unlock;
 573
 574         inode_inc_iversion(inode);
 575         inode->i_mtime = inode->i_atime = inode->i_ctime =
 576                 EXFAT_I(inode)->i_crtime = current_time(inode);
 577         exfat_truncate_atime(&inode->i_atime);
 578         /* timestamp is already written, so mark_inode_dirty() is unneeded. */
 579
 580         d_instantiate(dentry, inode);
 581 unlock:
 582         mutex_unlock(&EXFAT_SB(sb)->s_lock);
 583         return err;
 584 }
 585
 586 /* lookup a file */
 587 static int exfat_find(struct inode *dir, struct qstr *qname,
 588                 struct exfat_dir_entry *info)
 589 {
 590         int ret, dentry, num_entries, count;
 591         struct exfat_chain cdir;
 592         struct exfat_uni_name uni_name;
 593         struct super_block *sb = dir->i_sb;
 594         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 595         struct exfat_inode_info *ei = EXFAT_I(dir);
 596         struct exfat_dentry *ep, *ep2;
 597         struct exfat_entry_set_cache *es;
 598         /* for optimized dir & entry to prevent long traverse of cluster chain */
 599         struct exfat_hint hint_opt;
 600
 601         if (qname->len == 0)
 602                 return -ENOENT;
 603
 604         /* check the validity of directory name in the given pathname */
 605         ret = exfat_resolve_path_for_lookup(dir, qname->name, &cdir, &uni_name);
 606         if (ret)
 607                 return ret;
 608
 609         num_entries = exfat_calc_num_entries(&uni_name);
 610         if (num_entries < 0)
 611                 return num_entries;
 612
 613         /* check the validation of hint_stat and initialize it if required */
 614         if (ei->version != (inode_peek_iversion_raw(dir) & 0xffffffff)) {
 615                 ei->hint_stat.clu = cdir.dir;
 616                 ei->hint_stat.eidx = 0;
 617                 ei->version = (inode_peek_iversion_raw(dir) & 0xffffffff);
 618                 ei->hint_femp.eidx = EXFAT_HINT_NONE;
 619         }
 620
 621         /* search the file name for directories */
 622         dentry = exfat_find_dir_entry(sb, ei, &cdir, &uni_name,
 623                         num_entries, TYPE_ALL, &hint_opt);
 624
 625         if (dentry < 0)
 626                 return dentry; /* -error value */
 627
 628         info->dir = cdir;
 629         info->entry = dentry;
 630         info->num_subdirs = 0;
 631
 632         /* adjust cdir to the optimized value */
 633         cdir.dir = hint_opt.clu;
 634         if (cdir.flags & ALLOC_NO_FAT_CHAIN)
 635                 cdir.size -= dentry / sbi->dentries_per_clu;
 636         dentry = hint_opt.eidx;
 637         es = exfat_get_dentry_set(sb, &cdir, dentry, ES_2_ENTRIES);
 638         if (!es)
 639                 return -EIO;
 640         ep = exfat_get_dentry_cached(es, 0);
 641         ep2 = exfat_get_dentry_cached(es, 1);
 642
 643         info->type = exfat_get_entry_type(ep);
 644         info->attr = le16_to_cpu(ep->dentry.file.attr);
 645         info->size = le64_to_cpu(ep2->dentry.stream.valid_size);
 646         if ((info->type == TYPE_FILE) && (info->size == 0)) {
 647                 info->flags = ALLOC_NO_FAT_CHAIN;
 648                 info->start_clu = EXFAT_EOF_CLUSTER;
 649         } else {
 650                 info->flags = ep2->dentry.stream.flags;
 651                 info->start_clu =
 652                         le32_to_cpu(ep2->dentry.stream.start_clu);
 653         }
 654
 655         exfat_get_entry_time(sbi, &info->crtime,
 656                              ep->dentry.file.create_tz,
 657                              ep->dentry.file.create_time,
 658                              ep->dentry.file.create_date,
 659                              ep->dentry.file.create_time_cs);
 660         exfat_get_entry_time(sbi, &info->mtime,
 661                              ep->dentry.file.modify_tz,
 662                              ep->dentry.file.modify_time,
 663                              ep->dentry.file.modify_date,
 664                              ep->dentry.file.modify_time_cs);
 665         exfat_get_entry_time(sbi, &info->atime,
 666                              ep->dentry.file.access_tz,
 667                              ep->dentry.file.access_time,
 668                              ep->dentry.file.access_date,
 669                              0);
 670         exfat_free_dentry_set(es, false);
 671
 672         if (ei->start_clu == EXFAT_FREE_CLUSTER) {
 673                 exfat_fs_error(sb,
 674                                "non-zero size file starts with zero cluster (size : %llu, p_dir : %u, entry : 0x%08x)",
 675                                i_size_read(dir), ei->dir.dir, ei->entry);
 676                 return -EIO;
 677         }
 678
 679         if (info->type == TYPE_DIR) {
 680                 exfat_chain_set(&cdir, info->start_clu,
 681                                 EXFAT_B_TO_CLU(info->size, sbi), info->flags);
 682                 count = exfat_count_dir_entries(sb, &cdir);
 683                 if (count < 0)
 684                         return -EIO;
 685
 686                 info->num_subdirs = count + EXFAT_MIN_SUBDIR;
 687         }
 688         return 0;
 689 }
 690
 691 static int exfat_d_anon_disconn(struct dentry *dentry)
 692 {
 693         return IS_ROOT(dentry) && (dentry->d_flags & DCACHE_DISCONNECTED);
 694 }
 695
 696 static struct dentry *exfat_lookup(struct inode *dir, struct dentry *dentry,
 697                 unsigned int flags)
 698 {
 699         struct super_block *sb = dir->i_sb;
 700         struct inode *inode;
 701         struct dentry *alias;
 702         struct exfat_dir_entry info;
 703         int err;
 704         loff_t i_pos;
 705         mode_t i_mode;
 706
 707         mutex_lock(&EXFAT_SB(sb)->s_lock);
 708         err = exfat_find(dir, &dentry->d_name, &info);
 709         if (err) {
 710                 if (err == -ENOENT) {
 711                         inode = NULL;
 712                         goto out;
 713                 }
 714                 goto unlock;
 715         }
 716
 717         i_pos = exfat_make_i_pos(&info);
 718         inode = exfat_build_inode(sb, &info, i_pos);
 719         err = PTR_ERR_OR_ZERO(inode);
 720         if (err)
 721                 goto unlock;
 722
 723         i_mode = inode->i_mode;
 724         alias = d_find_alias(inode);
 725
 726         /*
 727          * Checking "alias->d_parent == dentry->d_parent" to make sure
 728          * FS is not corrupted (especially double linked dir).
 729          */
 730         if (alias && alias->d_parent == dentry->d_parent &&
 731                         !exfat_d_anon_disconn(alias)) {
 732
 733                 /*
 734                  * Unhashed alias is able to exist because of revalidate()
 735                  * called by lookup_fast. You can easily make this status
 736                  * by calling create and lookup concurrently
 737                  * In such case, we reuse an alias instead of new dentry
 738                  */
 739                 if (d_unhashed(alias)) {
 740                         WARN_ON(alias->d_name.hash_len !=
 741                                 dentry->d_name.hash_len);
 742                         exfat_info(sb, "rehashed a dentry(%p) in read lookup",
 743                                    alias);
 744                         d_drop(dentry);
 745                         d_rehash(alias);
 746                 } else if (!S_ISDIR(i_mode)) {
 747                         /*
 748                          * This inode has non anonymous-DCACHE_DISCONNECTED
 749                          * dentry. This means, the user did ->lookup() by an
 750                          * another name (longname vs 8.3 alias of it) in past.
 751                          *
 752                          * Switch to new one for reason of locality if possible.
 753                          */
 754                         d_move(alias, dentry);
 755                 }
 756                 iput(inode);
 757                 mutex_unlock(&EXFAT_SB(sb)->s_lock);
 758                 return alias;
 759         }
 760         dput(alias);
 761 out:
 762         mutex_unlock(&EXFAT_SB(sb)->s_lock);
 763         if (!inode)
 764                 exfat_d_version_set(dentry, inode_query_iversion(dir));
 765
 766         return d_splice_alias(inode, dentry);
 767 unlock:
 768         mutex_unlock(&EXFAT_SB(sb)->s_lock);
 769         return ERR_PTR(err);
 770 }
 771
 772 /* remove an entry, BUT don't truncate */
 773 static int exfat_unlink(struct inode *dir, struct dentry *dentry)
 774 {
 775         struct exfat_chain cdir;
 776         struct exfat_dentry *ep;
 777         struct super_block *sb = dir->i_sb;
 778         struct inode *inode = dentry->d_inode;
 779         struct exfat_inode_info *ei = EXFAT_I(inode);
 780         struct buffer_head *bh;
 781         int num_entries, entry, err = 0;
 782
 783         mutex_lock(&EXFAT_SB(sb)->s_lock);
 784         exfat_chain_dup(&cdir, &ei->dir);
 785         entry = ei->entry;
 786         if (ei->dir.dir == DIR_DELETED) {
 787                 exfat_err(sb, "abnormal access to deleted dentry");
 788                 err = -ENOENT;
 789                 goto unlock;
 790         }
 791
 792         ep = exfat_get_dentry(sb, &cdir, entry, &bh);
 793         if (!ep) {
 794                 err = -EIO;
 795                 goto unlock;
 796         }
 797         num_entries = exfat_count_ext_entries(sb, &cdir, entry, ep);
 798         if (num_entries < 0) {
 799                 err = -EIO;
 800                 brelse(bh);
 801                 goto unlock;
 802         }
 803         num_entries++;
 804         brelse(bh);
 805
 806         exfat_set_volume_dirty(sb);
 807         /* update the directory entry */
 808         if (exfat_remove_entries(dir, &cdir, entry, 0, num_entries)) {
 809                 err = -EIO;
 810                 goto unlock;
 811         }
 812
 813         /* This doesn't modify ei */
 814         ei->dir.dir = DIR_DELETED;
 815         exfat_clear_volume_dirty(sb);
 816
 817         inode_inc_iversion(dir);
 818         dir->i_mtime = dir->i_atime = current_time(dir);
 819         exfat_truncate_atime(&dir->i_atime);
 820         if (IS_DIRSYNC(dir))
 821                 exfat_sync_inode(dir);
 822         else
 823                 mark_inode_dirty(dir);
 824
 825         clear_nlink(inode);
 826         inode->i_mtime = inode->i_atime = current_time(inode);
 827         exfat_truncate_atime(&inode->i_atime);
 828         exfat_unhash_inode(inode);
 829         exfat_d_version_set(dentry, inode_query_iversion(dir));
 830 unlock:
 831         mutex_unlock(&EXFAT_SB(sb)->s_lock);
 832         return err;
 833 }
 834
 835 static int exfat_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
 836                        struct dentry *dentry, umode_t mode)
 837 {
 838         struct super_block *sb = dir->i_sb;
 839         struct inode *inode;
 840         struct exfat_dir_entry info;
 841         struct exfat_chain cdir;
 842         loff_t i_pos;
 843         int err;
 844
 845         mutex_lock(&EXFAT_SB(sb)->s_lock);
 846         exfat_set_volume_dirty(sb);
 847         err = exfat_add_entry(dir, dentry->d_name.name, &cdir, TYPE_DIR,
 848                 &info);
 849         exfat_clear_volume_dirty(sb);
 850         if (err)
 851                 goto unlock;
 852
 853         inode_inc_iversion(dir);
 854         dir->i_ctime = dir->i_mtime = current_time(dir);
 855         if (IS_DIRSYNC(dir))
 856                 exfat_sync_inode(dir);
 857         else
 858                 mark_inode_dirty(dir);
 859         inc_nlink(dir);
 860
 861         i_pos = exfat_make_i_pos(&info);
 862         inode = exfat_build_inode(sb, &info, i_pos);
 863         err = PTR_ERR_OR_ZERO(inode);
 864         if (err)
 865                 goto unlock;
 866
 867         inode_inc_iversion(inode);
 868         inode->i_mtime = inode->i_atime = inode->i_ctime =
 869                 EXFAT_I(inode)->i_crtime = current_time(inode);
 870         exfat_truncate_atime(&inode->i_atime);
 871         /* timestamp is already written, so mark_inode_dirty() is unneeded. */
 872
 873         d_instantiate(dentry, inode);
 874
 875 unlock:
 876         mutex_unlock(&EXFAT_SB(sb)->s_lock);
 877         return err;
 878 }
 879
 880 static int exfat_check_dir_empty(struct super_block *sb,
 881                 struct exfat_chain *p_dir)
 882 {
 883         int i, dentries_per_clu;
 884         unsigned int type;
 885         struct exfat_chain clu;
 886         struct exfat_dentry *ep;
 887         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 888         struct buffer_head *bh;
 889
 890         dentries_per_clu = sbi->dentries_per_clu;
 891
 892         exfat_chain_dup(&clu, p_dir);
 893
 894         while (clu.dir != EXFAT_EOF_CLUSTER) {
 895                 for (i = 0; i < dentries_per_clu; i++) {
 896                         ep = exfat_get_dentry(sb, &clu, i, &bh);
 897                         if (!ep)
 898                                 return -EIO;
 899                         type = exfat_get_entry_type(ep);
 900                         brelse(bh);
 901                         if (type == TYPE_UNUSED)
 902                                 return 0;
 903
 904                         if (type != TYPE_FILE && type != TYPE_DIR)
 905                                 continue;
 906
 907                         return -ENOTEMPTY;
 908                 }
 909
 910                 if (clu.flags == ALLOC_NO_FAT_CHAIN) {
 911                         if (--clu.size > 0)
 912                                 clu.dir++;
 913                         else
 914                                 clu.dir = EXFAT_EOF_CLUSTER;
 915                 } else {
 916                         if (exfat_get_next_cluster(sb, &(clu.dir)))
 917                                 return -EIO;
 918                 }
 919         }
 920
 921         return 0;
 922 }
 923
 924 static int exfat_rmdir(struct inode *dir, struct dentry *dentry)
 925 {
 926         struct inode *inode = dentry->d_inode;
 927         struct exfat_dentry *ep;
 928         struct exfat_chain cdir, clu_to_free;
 929         struct super_block *sb = inode->i_sb;
 930         struct exfat_sb_info *sbi = EXFAT_SB(sb);
 931         struct exfat_inode_info *ei = EXFAT_I(inode);
 932         struct buffer_head *bh;
 933         int num_entries, entry, err;
 934
 935         mutex_lock(&EXFAT_SB(inode->i_sb)->s_lock);
 936
 937         exfat_chain_dup(&cdir, &ei->dir);
 938         entry = ei->entry;
 939
 940         if (ei->dir.dir == DIR_DELETED) {
 941                 exfat_err(sb, "abnormal access to deleted dentry");
 942                 err = -ENOENT;
 943                 goto unlock;
 944         }
 945
 946         exfat_chain_set(&clu_to_free, ei->start_clu,
 947                 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(inode), sbi), ei->flags);
 948
 949         err = exfat_check_dir_empty(sb, &clu_to_free);
 950         if (err) {
 951                 if (err == -EIO)
 952                         exfat_err(sb, "failed to exfat_check_dir_empty : err(%d)",
 953                                   err);
 954                 goto unlock;
 955         }
 956
 957         ep = exfat_get_dentry(sb, &cdir, entry, &bh);
 958         if (!ep) {
 959                 err = -EIO;
 960                 goto unlock;
 961         }
 962
 963         num_entries = exfat_count_ext_entries(sb, &cdir, entry, ep);
 964         if (num_entries < 0) {
 965                 err = -EIO;
 966                 brelse(bh);
 967                 goto unlock;
 968         }
 969         num_entries++;
 970         brelse(bh);
 971
 972         exfat_set_volume_dirty(sb);
 973         err = exfat_remove_entries(dir, &cdir, entry, 0, num_entries);
 974         if (err) {
 975                 exfat_err(sb, "failed to exfat_remove_entries : err(%d)", err);
 976                 goto unlock;
 977         }
 978         ei->dir.dir = DIR_DELETED;
 979         exfat_clear_volume_dirty(sb);
 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->entry = newentry;
1066         } else {
1067                 if (exfat_get_entry_type(epold) == TYPE_FILE) {
1068                         epold->dentry.file.attr |= cpu_to_le16(ATTR_ARCHIVE);
1069                         ei->attr |= ATTR_ARCHIVE;
1070                 }
1071                 exfat_update_bh(old_bh, sync);
1072                 brelse(old_bh);
1073                 ret = exfat_init_ext_entry(inode, p_dir, oldentry,
1074                         num_new_entries, p_uniname);
1075                 if (ret)
1076                         return ret;
1077
1078                 exfat_remove_entries(inode, p_dir, oldentry, num_new_entries,
1079                         num_old_entries);
1080         }
1081         return 0;
1082 }
1083
1084 static int exfat_move_file(struct inode *inode, struct exfat_chain *p_olddir,
1085                 int oldentry, struct exfat_chain *p_newdir,
1086                 struct exfat_uni_name *p_uniname, struct exfat_inode_info *ei)
1087 {
1088         int ret, newentry, num_new_entries, num_old_entries;
1089         struct exfat_dentry *epmov, *epnew;
1090         struct super_block *sb = inode->i_sb;
1091         struct buffer_head *mov_bh, *new_bh;
1092
1093         epmov = exfat_get_dentry(sb, p_olddir, oldentry, &mov_bh);
1094         if (!epmov)
1095                 return -EIO;
1096
1097         num_old_entries = exfat_count_ext_entries(sb, p_olddir, oldentry,
1098                 epmov);
1099         if (num_old_entries < 0)
1100                 return -EIO;
1101         num_old_entries++;
1102
1103         num_new_entries = exfat_calc_num_entries(p_uniname);
1104         if (num_new_entries < 0)
1105                 return num_new_entries;
1106
1107         newentry = exfat_find_empty_entry(inode, p_newdir, num_new_entries);
1108         if (newentry < 0)
1109                 return newentry; /* -EIO or -ENOSPC */
1110
1111         epnew = exfat_get_dentry(sb, p_newdir, newentry, &new_bh);
1112         if (!epnew)
1113                 return -EIO;
1114
1115         *epnew = *epmov;
1116         if (exfat_get_entry_type(epnew) == TYPE_FILE) {
1117                 epnew->dentry.file.attr |= cpu_to_le16(ATTR_ARCHIVE);
1118                 ei->attr |= ATTR_ARCHIVE;
1119         }
1120         exfat_update_bh(new_bh, IS_DIRSYNC(inode));
1121         brelse(mov_bh);
1122         brelse(new_bh);
1123
1124         epmov = exfat_get_dentry(sb, p_olddir, oldentry + 1, &mov_bh);
1125         if (!epmov)
1126                 return -EIO;
1127         epnew = exfat_get_dentry(sb, p_newdir, newentry + 1, &new_bh);
1128         if (!epnew) {
1129                 brelse(mov_bh);
1130                 return -EIO;
1131         }
1132
1133         *epnew = *epmov;
1134         exfat_update_bh(new_bh, IS_DIRSYNC(inode));
1135         brelse(mov_bh);
1136         brelse(new_bh);
1137
1138         ret = exfat_init_ext_entry(inode, p_newdir, newentry, num_new_entries,
1139                 p_uniname);
1140         if (ret)
1141                 return ret;
1142
1143         exfat_remove_entries(inode, p_olddir, oldentry, 0, num_old_entries);
1144
1145         exfat_chain_set(&ei->dir, p_newdir->dir, p_newdir->size,
1146                 p_newdir->flags);
1147
1148         ei->entry = newentry;
1149         return 0;
1150 }
1151
1152 static void exfat_update_parent_info(struct exfat_inode_info *ei,
1153                 struct inode *parent_inode)
1154 {
1155         struct exfat_sb_info *sbi = EXFAT_SB(parent_inode->i_sb);
1156         struct exfat_inode_info *parent_ei = EXFAT_I(parent_inode);
1157         loff_t parent_isize = i_size_read(parent_inode);
1158
1159         /*
1160          * the problem that struct exfat_inode_info caches wrong parent info.
1161          *
1162          * because of flag-mismatch of ei->dir,
1163          * there is abnormal traversing cluster chain.
1164          */
1165         if (unlikely(parent_ei->flags != ei->dir.flags ||
1166                      parent_isize != EXFAT_CLU_TO_B(ei->dir.size, sbi) ||
1167                      parent_ei->start_clu != ei->dir.dir)) {
1168                 exfat_chain_set(&ei->dir, parent_ei->start_clu,
1169                         EXFAT_B_TO_CLU_ROUND_UP(parent_isize, sbi),
1170                         parent_ei->flags);
1171         }
1172 }
1173
1174 /* rename or move a old file into a new file */
1175 static int __exfat_rename(struct inode *old_parent_inode,
1176                 struct exfat_inode_info *ei, struct inode *new_parent_inode,
1177                 struct dentry *new_dentry)
1178 {
1179         int ret;
1180         int dentry;
1181         struct exfat_chain olddir, newdir;
1182         struct exfat_chain *p_dir = NULL;
1183         struct exfat_uni_name uni_name;
1184         struct exfat_dentry *ep;
1185         struct super_block *sb = old_parent_inode->i_sb;
1186         struct exfat_sb_info *sbi = EXFAT_SB(sb);
1187         const unsigned char *new_path = new_dentry->d_name.name;
1188         struct inode *new_inode = new_dentry->d_inode;
1189         int num_entries;
1190         struct exfat_inode_info *new_ei = NULL;
1191         unsigned int new_entry_type = TYPE_UNUSED;
1192         int new_entry = 0;
1193         struct buffer_head *old_bh, *new_bh = NULL;
1194
1195         /* check the validity of pointer parameters */
1196         if (new_path == NULL || strlen(new_path) == 0)
1197                 return -EINVAL;
1198
1199         if (ei->dir.dir == DIR_DELETED) {
1200                 exfat_err(sb, "abnormal access to deleted source dentry");
1201                 return -ENOENT;
1202         }
1203
1204         exfat_update_parent_info(ei, old_parent_inode);
1205
1206         exfat_chain_dup(&olddir, &ei->dir);
1207         dentry = ei->entry;
1208
1209         ep = exfat_get_dentry(sb, &olddir, dentry, &old_bh);
1210         if (!ep) {
1211                 ret = -EIO;
1212                 goto out;
1213         }
1214         brelse(old_bh);
1215
1216         /* check whether new dir is existing directory and empty */
1217         if (new_inode) {
1218                 ret = -EIO;
1219                 new_ei = EXFAT_I(new_inode);
1220
1221                 if (new_ei->dir.dir == DIR_DELETED) {
1222                         exfat_err(sb, "abnormal access to deleted target dentry");
1223                         goto out;
1224                 }
1225
1226                 exfat_update_parent_info(new_ei, new_parent_inode);
1227
1228                 p_dir = &(new_ei->dir);
1229                 new_entry = new_ei->entry;
1230                 ep = exfat_get_dentry(sb, p_dir, new_entry, &new_bh);
1231                 if (!ep)
1232                         goto out;
1233
1234                 new_entry_type = exfat_get_entry_type(ep);
1235                 brelse(new_bh);
1236
1237                 /* if new_inode exists, update ei */
1238                 if (new_entry_type == TYPE_DIR) {
1239                         struct exfat_chain new_clu;
1240
1241                         new_clu.dir = new_ei->start_clu;
1242                         new_clu.size =
1243                                 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode),
1244                                 sbi);
1245                         new_clu.flags = new_ei->flags;
1246
1247                         ret = exfat_check_dir_empty(sb, &new_clu);
1248                         if (ret)
1249                                 goto out;
1250                 }
1251         }
1252
1253         /* check the validity of directory name in the given new pathname */
1254         ret = exfat_resolve_path(new_parent_inode, new_path, &newdir,
1255                         &uni_name);
1256         if (ret)
1257                 goto out;
1258
1259         exfat_set_volume_dirty(sb);
1260
1261         if (olddir.dir == newdir.dir)
1262                 ret = exfat_rename_file(new_parent_inode, &olddir, dentry,
1263                                 &uni_name, ei);
1264         else
1265                 ret = exfat_move_file(new_parent_inode, &olddir, dentry,
1266                                 &newdir, &uni_name, ei);
1267
1268         if (!ret && new_inode) {
1269                 /* delete entries of new_dir */
1270                 ep = exfat_get_dentry(sb, p_dir, new_entry, &new_bh);
1271                 if (!ep) {
1272                         ret = -EIO;
1273                         goto del_out;
1274                 }
1275
1276                 num_entries = exfat_count_ext_entries(sb, p_dir, new_entry, ep);
1277                 if (num_entries < 0) {
1278                         ret = -EIO;
1279                         goto del_out;
1280                 }
1281                 brelse(new_bh);
1282
1283                 if (exfat_remove_entries(new_inode, p_dir, new_entry, 0,
1284                                 num_entries + 1)) {
1285                         ret = -EIO;
1286                         goto del_out;
1287                 }
1288
1289                 /* Free the clusters if new_inode is a dir(as if exfat_rmdir) */
1290                 if (new_entry_type == TYPE_DIR) {
1291                         /* new_ei, new_clu_to_free */
1292                         struct exfat_chain new_clu_to_free;
1293
1294                         exfat_chain_set(&new_clu_to_free, new_ei->start_clu,
1295                                 EXFAT_B_TO_CLU_ROUND_UP(i_size_read(new_inode),
1296                                 sbi), new_ei->flags);
1297
1298                         if (exfat_free_cluster(new_inode, &new_clu_to_free)) {
1299                                 /* just set I/O error only */
1300                                 ret = -EIO;
1301                         }
1302
1303                         i_size_write(new_inode, 0);
1304                         new_ei->start_clu = EXFAT_EOF_CLUSTER;
1305                         new_ei->flags = ALLOC_NO_FAT_CHAIN;
1306                 }
1307 del_out:
1308                 /* Update new_inode ei
1309                  * Prevent syncing removed new_inode
1310                  * (new_ei is already initialized above code ("if (new_inode)")
1311                  */
1312                 new_ei->dir.dir = DIR_DELETED;
1313         }
1314         exfat_clear_volume_dirty(sb);
1315 out:
1316         return ret;
1317 }
1318
1319 static int exfat_rename(struct user_namespace *mnt_userns,
1320                         struct inode *old_dir, struct dentry *old_dentry,
1321                         struct inode *new_dir, struct dentry *new_dentry,
1322                         unsigned int flags)
1323 {
1324         struct inode *old_inode, *new_inode;
1325         struct super_block *sb = old_dir->i_sb;
1326         loff_t i_pos;
1327         int err;
1328
1329         /*
1330          * The VFS already checks for existence, so for local filesystems
1331          * the RENAME_NOREPLACE implementation is equivalent to plain rename.
1332          * Don't support any other flags
1333          */
1334         if (flags & ~RENAME_NOREPLACE)
1335                 return -EINVAL;
1336
1337         mutex_lock(&EXFAT_SB(sb)->s_lock);
1338         old_inode = old_dentry->d_inode;
1339         new_inode = new_dentry->d_inode;
1340
1341         err = __exfat_rename(old_dir, EXFAT_I(old_inode), new_dir, new_dentry);
1342         if (err)
1343                 goto unlock;
1344
1345         inode_inc_iversion(new_dir);
1346         new_dir->i_ctime = new_dir->i_mtime = new_dir->i_atime =
1347                 EXFAT_I(new_dir)->i_crtime = current_time(new_dir);
1348         exfat_truncate_atime(&new_dir->i_atime);
1349         if (IS_DIRSYNC(new_dir))
1350                 exfat_sync_inode(new_dir);
1351         else
1352                 mark_inode_dirty(new_dir);
1353
1354         i_pos = ((loff_t)EXFAT_I(old_inode)->dir.dir << 32) |
1355                 (EXFAT_I(old_inode)->entry & 0xffffffff);
1356         exfat_unhash_inode(old_inode);
1357         exfat_hash_inode(old_inode, i_pos);
1358         if (IS_DIRSYNC(new_dir))
1359                 exfat_sync_inode(old_inode);
1360         else
1361                 mark_inode_dirty(old_inode);
1362
1363         if (S_ISDIR(old_inode->i_mode) && old_dir != new_dir) {
1364                 drop_nlink(old_dir);
1365                 if (!new_inode)
1366                         inc_nlink(new_dir);
1367         }
1368
1369         inode_inc_iversion(old_dir);
1370         old_dir->i_ctime = old_dir->i_mtime = current_time(old_dir);
1371         if (IS_DIRSYNC(old_dir))
1372                 exfat_sync_inode(old_dir);
1373         else
1374                 mark_inode_dirty(old_dir);
1375
1376         if (new_inode) {
1377                 exfat_unhash_inode(new_inode);
1378
1379                 /* skip drop_nlink if new_inode already has been dropped */
1380                 if (new_inode->i_nlink) {
1381                         drop_nlink(new_inode);
1382                         if (S_ISDIR(new_inode->i_mode))
1383                                 drop_nlink(new_inode);
1384                 } else {
1385                         exfat_warn(sb, "abnormal access to an inode dropped");
1386                         WARN_ON(new_inode->i_nlink == 0);
1387                 }
1388                 new_inode->i_ctime = EXFAT_I(new_inode)->i_crtime =
1389                         current_time(new_inode);
1390         }
1391
1392 unlock:
1393         mutex_unlock(&EXFAT_SB(sb)->s_lock);
1394         return err;
1395 }
1396
1397 const struct inode_operations exfat_dir_inode_operations = {
1398         .create         = exfat_create,
1399         .lookup         = exfat_lookup,
1400         .unlink         = exfat_unlink,
1401         .mkdir          = exfat_mkdir,
1402         .rmdir          = exfat_rmdir,
1403         .rename         = exfat_rename,
1404         .setattr        = exfat_setattr,
1405         .getattr        = exfat_getattr,
1406 };