fs/cifs/dir.c

   1 // SPDX-License-Identifier: LGPL-2.1
   2 /*
   3  *
   4  *   vfs operations that deal with dentries
   5  *
   6  *   Copyright (C) International Business Machines  Corp., 2002,2009
   7  *   Author(s): Steve French (sfrench@us.ibm.com)
   8  *
   9  */
  10 #include <linux/fs.h>
  11 #include <linux/stat.h>
  12 #include <linux/slab.h>
  13 #include <linux/namei.h>
  14 #include <linux/mount.h>
  15 #include <linux/file.h>
  16 #include "cifsfs.h"
  17 #include "cifspdu.h"
  18 #include "cifsglob.h"
  19 #include "cifsproto.h"
  20 #include "cifs_debug.h"
  21 #include "cifs_fs_sb.h"
  22 #include "cifs_unicode.h"
  23 #include "fs_context.h"
  24 #include "cifs_ioctl.h"
  25 #include "fscache.h"
  26
  27 static void
  28 renew_parental_timestamps(struct dentry *direntry)
  29 {
  30         /* BB check if there is a way to get the kernel to do this or if we
  31            really need this */
  32         do {
  33                 cifs_set_time(direntry, jiffies);
  34                 direntry = direntry->d_parent;
  35         } while (!IS_ROOT(direntry));
  36 }
  37
  38 char *
  39 cifs_build_path_to_root(struct smb3_fs_context *ctx, struct cifs_sb_info *cifs_sb,
  40                         struct cifs_tcon *tcon, int add_treename)
  41 {
  42         int pplen = ctx->prepath ? strlen(ctx->prepath) + 1 : 0;
  43         int dfsplen;
  44         char *full_path = NULL;
  45
  46         /* if no prefix path, simply set path to the root of share to "" */
  47         if (pplen == 0) {
  48                 full_path = kzalloc(1, GFP_KERNEL);
  49                 return full_path;
  50         }
  51
  52         if (add_treename)
  53                 dfsplen = strnlen(tcon->tree_name, MAX_TREE_SIZE + 1);
  54         else
  55                 dfsplen = 0;
  56
  57         full_path = kmalloc(dfsplen + pplen + 1, GFP_KERNEL);
  58         if (full_path == NULL)
  59                 return full_path;
  60
  61         if (dfsplen)
  62                 memcpy(full_path, tcon->tree_name, dfsplen);
  63         full_path[dfsplen] = CIFS_DIR_SEP(cifs_sb);
  64         memcpy(full_path + dfsplen + 1, ctx->prepath, pplen);
  65         convert_delimiter(full_path, CIFS_DIR_SEP(cifs_sb));
  66         return full_path;
  67 }
  68
  69 /* Note: caller must free return buffer */
  70 const char *
  71 build_path_from_dentry(struct dentry *direntry, void *page)
  72 {
  73         struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
  74         struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
  75         bool prefix = tcon->Flags & SMB_SHARE_IS_IN_DFS;
  76
  77         return build_path_from_dentry_optional_prefix(direntry, page,
  78                                                       prefix);
  79 }
  80
  81 char *
  82 build_path_from_dentry_optional_prefix(struct dentry *direntry, void *page,
  83                                        bool prefix)
  84 {
  85         int dfsplen;
  86         int pplen = 0;
  87         struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
  88         struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
  89         char dirsep = CIFS_DIR_SEP(cifs_sb);
  90         char *s;
  91
  92         if (unlikely(!page))
  93                 return ERR_PTR(-ENOMEM);
  94
  95         if (prefix)
  96                 dfsplen = strnlen(tcon->tree_name, MAX_TREE_SIZE + 1);
  97         else
  98                 dfsplen = 0;
  99
 100         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH)
 101                 pplen = cifs_sb->prepath ? strlen(cifs_sb->prepath) + 1 : 0;
 102
 103         s = dentry_path_raw(direntry, page, PATH_MAX);
 104         if (IS_ERR(s))
 105                 return s;
 106         if (!s[1])      // for root we want "", not "/"
 107                 s++;
 108         if (s < (char *)page + pplen + dfsplen)
 109                 return ERR_PTR(-ENAMETOOLONG);
 110         if (pplen) {
 111                 cifs_dbg(FYI, "using cifs_sb prepath <%s>\n", cifs_sb->prepath);
 112                 s -= pplen;
 113                 memcpy(s + 1, cifs_sb->prepath, pplen - 1);
 114                 *s = '/';
 115         }
 116         if (dirsep != '/') {
 117                 /* BB test paths to Windows with '/' in the midst of prepath */
 118                 char *p;
 119
 120                 for (p = s; *p; p++)
 121                         if (*p == '/')
 122                                 *p = dirsep;
 123         }
 124         if (dfsplen) {
 125                 s -= dfsplen;
 126                 memcpy(s, tcon->tree_name, dfsplen);
 127                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS) {
 128                         int i;
 129                         for (i = 0; i < dfsplen; i++) {
 130                                 if (s[i] == '\\')
 131                                         s[i] = '/';
 132                         }
 133                 }
 134         }
 135         return s;
 136 }
 137
 138 /*
 139  * Don't allow path components longer than the server max.
 140  * Don't allow the separator character in a path component.
 141  * The VFS will not allow "/", but "\" is allowed by posix.
 142  */
 143 static int
 144 check_name(struct dentry *direntry, struct cifs_tcon *tcon)
 145 {
 146         struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
 147         int i;
 148
 149         if (unlikely(tcon->fsAttrInfo.MaxPathNameComponentLength &&
 150                      direntry->d_name.len >
 151                      le32_to_cpu(tcon->fsAttrInfo.MaxPathNameComponentLength)))
 152                 return -ENAMETOOLONG;
 153
 154         if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS)) {
 155                 for (i = 0; i < direntry->d_name.len; i++) {
 156                         if (direntry->d_name.name[i] == '\\') {
 157                                 cifs_dbg(FYI, "Invalid file name\n");
 158                                 return -EINVAL;
 159                         }
 160                 }
 161         }
 162         return 0;
 163 }
 164
 165
 166 /* Inode operations in similar order to how they appear in Linux file fs.h */
 167
 168 static int cifs_do_create(struct inode *inode, struct dentry *direntry, unsigned int xid,
 169                           struct tcon_link *tlink, unsigned int oflags, umode_t mode, __u32 *oplock,
 170                           struct cifs_fid *fid, struct cifs_open_info_data *buf)
 171 {
 172         int rc = -ENOENT;
 173         int create_options = CREATE_NOT_DIR;
 174         int desired_access;
 175         struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
 176         struct cifs_tcon *tcon = tlink_tcon(tlink);
 177         const char *full_path;
 178         void *page = alloc_dentry_path();
 179         struct inode *newinode = NULL;
 180         int disposition;
 181         struct TCP_Server_Info *server = tcon->ses->server;
 182         struct cifs_open_parms oparms;
 183
 184         *oplock = 0;
 185         if (tcon->ses->server->oplocks)
 186                 *oplock = REQ_OPLOCK;
 187
 188         full_path = build_path_from_dentry(direntry, page);
 189         if (IS_ERR(full_path)) {
 190                 free_dentry_path(page);
 191                 return PTR_ERR(full_path);
 192         }
 193
 194 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
 195         if (tcon->unix_ext && cap_unix(tcon->ses) && !tcon->broken_posix_open &&
 196             (CIFS_UNIX_POSIX_PATH_OPS_CAP &
 197                         le64_to_cpu(tcon->fsUnixInfo.Capability))) {
 198                 rc = cifs_posix_open(full_path, &newinode, inode->i_sb, mode,
 199                                      oflags, oplock, &fid->netfid, xid);
 200                 switch (rc) {
 201                 case 0:
 202                         if (newinode == NULL) {
 203                                 /* query inode info */
 204                                 goto cifs_create_get_file_info;
 205                         }
 206
 207                         if (S_ISDIR(newinode->i_mode)) {
 208                                 CIFSSMBClose(xid, tcon, fid->netfid);
 209                                 iput(newinode);
 210                                 rc = -EISDIR;
 211                                 goto out;
 212                         }
 213
 214                         if (!S_ISREG(newinode->i_mode)) {
 215                                 /*
 216                                  * The server may allow us to open things like
 217                                  * FIFOs, but the client isn't set up to deal
 218                                  * with that. If it's not a regular file, just
 219                                  * close it and proceed as if it were a normal
 220                                  * lookup.
 221                                  */
 222                                 CIFSSMBClose(xid, tcon, fid->netfid);
 223                                 goto cifs_create_get_file_info;
 224                         }
 225                         /* success, no need to query */
 226                         goto cifs_create_set_dentry;
 227
 228                 case -ENOENT:
 229                         goto cifs_create_get_file_info;
 230
 231                 case -EIO:
 232                 case -EINVAL:
 233                         /*
 234                          * EIO could indicate that (posix open) operation is not
 235                          * supported, despite what server claimed in capability
 236                          * negotiation.
 237                          *
 238                          * POSIX open in samba versions 3.3.1 and earlier could
 239                          * incorrectly fail with invalid parameter.
 240                          */
 241                         tcon->broken_posix_open = true;
 242                         break;
 243
 244                 case -EREMOTE:
 245                 case -EOPNOTSUPP:
 246                         /*
 247                          * EREMOTE indicates DFS junction, which is not handled
 248                          * in posix open.  If either that or op not supported
 249                          * returned, follow the normal lookup.
 250                          */
 251                         break;
 252
 253                 default:
 254                         goto out;
 255                 }
 256                 /*
 257                  * fallthrough to retry, using older open call, this is case
 258                  * where server does not support this SMB level, and falsely
 259                  * claims capability (also get here for DFS case which should be
 260                  * rare for path not covered on files)
 261                  */
 262         }
 263 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
 264
 265         desired_access = 0;
 266         if (OPEN_FMODE(oflags) & FMODE_READ)
 267                 desired_access |= GENERIC_READ; /* is this too little? */
 268         if (OPEN_FMODE(oflags) & FMODE_WRITE)
 269                 desired_access |= GENERIC_WRITE;
 270
 271         disposition = FILE_OVERWRITE_IF;
 272         if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
 273                 disposition = FILE_CREATE;
 274         else if ((oflags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))
 275                 disposition = FILE_OVERWRITE_IF;
 276         else if ((oflags & O_CREAT) == O_CREAT)
 277                 disposition = FILE_OPEN_IF;
 278         else
 279                 cifs_dbg(FYI, "Create flag not set in create function\n");
 280
 281         /*
 282          * BB add processing to set equivalent of mode - e.g. via CreateX with
 283          * ACLs
 284          */
 285
 286         if (!server->ops->open) {
 287                 rc = -ENOSYS;
 288                 goto out;
 289         }
 290
 291         /*
 292          * if we're not using unix extensions, see if we need to set
 293          * ATTR_READONLY on the create call
 294          */
 295         if (!tcon->unix_ext && (mode & S_IWUGO) == 0)
 296                 create_options |= CREATE_OPTION_READONLY;
 297
 298         oparms = (struct cifs_open_parms) {
 299                 .tcon = tcon,
 300                 .cifs_sb = cifs_sb,
 301                 .desired_access = desired_access,
 302                 .create_options = cifs_create_options(cifs_sb, create_options),
 303                 .disposition = disposition,
 304                 .path = full_path,
 305                 .fid = fid,
 306                 .mode = mode,
 307         };
 308         rc = server->ops->open(xid, &oparms, oplock, buf);
 309         if (rc) {
 310                 cifs_dbg(FYI, "cifs_create returned 0x%x\n", rc);
 311                 goto out;
 312         }
 313
 314 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
 315         /*
 316          * If Open reported that we actually created a file then we now have to
 317          * set the mode if possible.
 318          */
 319         if ((tcon->unix_ext) && (*oplock & CIFS_CREATE_ACTION)) {
 320                 struct cifs_unix_set_info_args args = {
 321                                 .mode   = mode,
 322                                 .ctime  = NO_CHANGE_64,
 323                                 .atime  = NO_CHANGE_64,
 324                                 .mtime  = NO_CHANGE_64,
 325                                 .device = 0,
 326                 };
 327
 328                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
 329                         args.uid = current_fsuid();
 330                         if (inode->i_mode & S_ISGID)
 331                                 args.gid = inode->i_gid;
 332                         else
 333                                 args.gid = current_fsgid();
 334                 } else {
 335                         args.uid = INVALID_UID; /* no change */
 336                         args.gid = INVALID_GID; /* no change */
 337                 }
 338                 CIFSSMBUnixSetFileInfo(xid, tcon, &args, fid->netfid,
 339                                        current->tgid);
 340         } else {
 341                 /*
 342                  * BB implement mode setting via Windows security
 343                  * descriptors e.g.
 344                  */
 345                 /* CIFSSMBWinSetPerms(xid,tcon,path,mode,-1,-1,nls);*/
 346
 347                 /* Could set r/o dos attribute if mode & 0222 == 0 */
 348         }
 349
 350 cifs_create_get_file_info:
 351         /* server might mask mode so we have to query for it */
 352         if (tcon->unix_ext)
 353                 rc = cifs_get_inode_info_unix(&newinode, full_path, inode->i_sb,
 354                                               xid);
 355         else {
 356 #else
 357         {
 358 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
 359                 /* TODO: Add support for calling POSIX query info here, but passing in fid */
 360                 rc = cifs_get_inode_info(&newinode, full_path, buf, inode->i_sb, xid, fid);
 361                 if (newinode) {
 362                         if (server->ops->set_lease_key)
 363                                 server->ops->set_lease_key(newinode, fid);
 364                         if ((*oplock & CIFS_CREATE_ACTION) && S_ISREG(newinode->i_mode)) {
 365                                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DYNPERM)
 366                                         newinode->i_mode = mode;
 367                                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
 368                                         newinode->i_uid = current_fsuid();
 369                                         if (inode->i_mode & S_ISGID)
 370                                                 newinode->i_gid = inode->i_gid;
 371                                         else
 372                                                 newinode->i_gid = current_fsgid();
 373                                 }
 374                         }
 375                 }
 376         }
 377
 378 #ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
 379 cifs_create_set_dentry:
 380 #endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
 381         if (rc != 0) {
 382                 cifs_dbg(FYI, "Create worked, get_inode_info failed rc = %d\n",
 383                          rc);
 384                 goto out_err;
 385         }
 386
 387         if (newinode)
 388                 if (S_ISDIR(newinode->i_mode)) {
 389                         rc = -EISDIR;
 390                         goto out_err;
 391                 }
 392
 393         d_drop(direntry);
 394         d_add(direntry, newinode);
 395
 396 out:
 397         free_dentry_path(page);
 398         return rc;
 399
 400 out_err:
 401         if (server->ops->close)
 402                 server->ops->close(xid, tcon, fid);
 403         if (newinode)
 404                 iput(newinode);
 405         goto out;
 406 }
 407
 408 int
 409 cifs_atomic_open(struct inode *inode, struct dentry *direntry,
 410                  struct file *file, unsigned oflags, umode_t mode)
 411 {
 412         int rc;
 413         unsigned int xid;
 414         struct tcon_link *tlink;
 415         struct cifs_tcon *tcon;
 416         struct TCP_Server_Info *server;
 417         struct cifs_fid fid = {};
 418         struct cifs_pending_open open;
 419         __u32 oplock;
 420         struct cifsFileInfo *file_info;
 421         struct cifs_open_info_data buf = {};
 422
 423         if (unlikely(cifs_forced_shutdown(CIFS_SB(inode->i_sb))))
 424                 return -EIO;
 425
 426         /*
 427          * Posix open is only called (at lookup time) for file create now. For
 428          * opens (rather than creates), because we do not know if it is a file
 429          * or directory yet, and current Samba no longer allows us to do posix
 430          * open on dirs, we could end up wasting an open call on what turns out
 431          * to be a dir. For file opens, we wait to call posix open till
 432          * cifs_open.  It could be added to atomic_open in the future but the
 433          * performance tradeoff of the extra network request when EISDIR or
 434          * EACCES is returned would have to be weighed against the 50% reduction
 435          * in network traffic in the other paths.
 436          */
 437         if (!(oflags & O_CREAT)) {
 438                 struct dentry *res;
 439
 440                 /*
 441                  * Check for hashed negative dentry. We have already revalidated
 442                  * the dentry and it is fine. No need to perform another lookup.
 443                  */
 444                 if (!d_in_lookup(direntry))
 445                         return -ENOENT;
 446
 447                 res = cifs_lookup(inode, direntry, 0);
 448                 if (IS_ERR(res))
 449                         return PTR_ERR(res);
 450
 451                 return finish_no_open(file, res);
 452         }
 453
 454         xid = get_xid();
 455
 456         cifs_dbg(FYI, "parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
 457                  inode, direntry, direntry);
 458
 459         tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));
 460         if (IS_ERR(tlink)) {
 461                 rc = PTR_ERR(tlink);
 462                 goto out_free_xid;
 463         }
 464
 465         tcon = tlink_tcon(tlink);
 466
 467         rc = check_name(direntry, tcon);
 468         if (rc)
 469                 goto out;
 470
 471         server = tcon->ses->server;
 472
 473         if (server->ops->new_lease_key)
 474                 server->ops->new_lease_key(&fid);
 475
 476         cifs_add_pending_open(&fid, tlink, &open);
 477
 478         rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode,
 479                             &oplock, &fid, &buf);
 480         if (rc) {
 481                 cifs_del_pending_open(&open);
 482                 goto out;
 483         }
 484
 485         if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
 486                 file->f_mode |= FMODE_CREATED;
 487
 488         rc = finish_open(file, direntry, generic_file_open);
 489         if (rc) {
 490                 if (server->ops->close)
 491                         server->ops->close(xid, tcon, &fid);
 492                 cifs_del_pending_open(&open);
 493                 goto out;
 494         }
 495
 496         if (file->f_flags & O_DIRECT &&
 497             CIFS_SB(inode->i_sb)->mnt_cifs_flags & CIFS_MOUNT_STRICT_IO) {
 498                 if (CIFS_SB(inode->i_sb)->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
 499                         file->f_op = &cifs_file_direct_nobrl_ops;
 500                 else
 501                         file->f_op = &cifs_file_direct_ops;
 502                 }
 503
 504         file_info = cifs_new_fileinfo(&fid, file, tlink, oplock, buf.symlink_target);
 505         if (file_info == NULL) {
 506                 if (server->ops->close)
 507                         server->ops->close(xid, tcon, &fid);
 508                 cifs_del_pending_open(&open);
 509                 rc = -ENOMEM;
 510                 goto out;
 511         }
 512
 513         fscache_use_cookie(cifs_inode_cookie(file_inode(file)),
 514                            file->f_mode & FMODE_WRITE);
 515
 516 out:
 517         cifs_put_tlink(tlink);
 518 out_free_xid:
 519         free_xid(xid);
 520         cifs_free_open_info(&buf);
 521         return rc;
 522 }
 523
 524 int cifs_create(struct user_namespace *mnt_userns, struct inode *inode,
 525                 struct dentry *direntry, umode_t mode, bool excl)
 526 {
 527         int rc;
 528         unsigned int xid = get_xid();
 529         /*
 530          * BB below access is probably too much for mknod to request
 531          *    but we have to do query and setpathinfo so requesting
 532          *    less could fail (unless we want to request getatr and setatr
 533          *    permissions (only).  At least for POSIX we do not have to
 534          *    request so much.
 535          */
 536         unsigned oflags = O_EXCL | O_CREAT | O_RDWR;
 537         struct tcon_link *tlink;
 538         struct cifs_tcon *tcon;
 539         struct TCP_Server_Info *server;
 540         struct cifs_fid fid;
 541         __u32 oplock;
 542         struct cifs_open_info_data buf = {};
 543
 544         cifs_dbg(FYI, "cifs_create parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
 545                  inode, direntry, direntry);
 546
 547         if (unlikely(cifs_forced_shutdown(CIFS_SB(inode->i_sb)))) {
 548                 rc = -EIO;
 549                 goto out_free_xid;
 550         }
 551
 552         tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));
 553         rc = PTR_ERR(tlink);
 554         if (IS_ERR(tlink))
 555                 goto out_free_xid;
 556
 557         tcon = tlink_tcon(tlink);
 558         server = tcon->ses->server;
 559
 560         if (server->ops->new_lease_key)
 561                 server->ops->new_lease_key(&fid);
 562
 563         rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode, &oplock, &fid, &buf);
 564         if (!rc && server->ops->close)
 565                 server->ops->close(xid, tcon, &fid);
 566
 567         cifs_free_open_info(&buf);
 568         cifs_put_tlink(tlink);
 569 out_free_xid:
 570         free_xid(xid);
 571         return rc;
 572 }
 573
 574 int cifs_mknod(struct user_namespace *mnt_userns, struct inode *inode,
 575                struct dentry *direntry, umode_t mode, dev_t device_number)
 576 {
 577         int rc = -EPERM;
 578         unsigned int xid;
 579         struct cifs_sb_info *cifs_sb;
 580         struct tcon_link *tlink;
 581         struct cifs_tcon *tcon;
 582         const char *full_path;
 583         void *page;
 584
 585         if (!old_valid_dev(device_number))
 586                 return -EINVAL;
 587
 588         cifs_sb = CIFS_SB(inode->i_sb);
 589         if (unlikely(cifs_forced_shutdown(cifs_sb)))
 590                 return -EIO;
 591
 592         tlink = cifs_sb_tlink(cifs_sb);
 593         if (IS_ERR(tlink))
 594                 return PTR_ERR(tlink);
 595
 596         page = alloc_dentry_path();
 597         tcon = tlink_tcon(tlink);
 598         xid = get_xid();
 599
 600         full_path = build_path_from_dentry(direntry, page);
 601         if (IS_ERR(full_path)) {
 602                 rc = PTR_ERR(full_path);
 603                 goto mknod_out;
 604         }
 605
 606         rc = tcon->ses->server->ops->make_node(xid, inode, direntry, tcon,
 607                                                full_path, mode,
 608                                                device_number);
 609
 610 mknod_out:
 611         free_dentry_path(page);
 612         free_xid(xid);
 613         cifs_put_tlink(tlink);
 614         return rc;
 615 }
 616
 617 struct dentry *
 618 cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,
 619             unsigned int flags)
 620 {
 621         unsigned int xid;
 622         int rc = 0; /* to get around spurious gcc warning, set to zero here */
 623         struct cifs_sb_info *cifs_sb;
 624         struct tcon_link *tlink;
 625         struct cifs_tcon *pTcon;
 626         struct inode *newInode = NULL;
 627         const char *full_path;
 628         void *page;
 629         int retry_count = 0;
 630
 631         xid = get_xid();
 632
 633         cifs_dbg(FYI, "parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
 634                  parent_dir_inode, direntry, direntry);
 635
 636         /* check whether path exists */
 637
 638         cifs_sb = CIFS_SB(parent_dir_inode->i_sb);
 639         tlink = cifs_sb_tlink(cifs_sb);
 640         if (IS_ERR(tlink)) {
 641                 free_xid(xid);
 642                 return ERR_CAST(tlink);
 643         }
 644         pTcon = tlink_tcon(tlink);
 645
 646         rc = check_name(direntry, pTcon);
 647         if (unlikely(rc)) {
 648                 cifs_put_tlink(tlink);
 649                 free_xid(xid);
 650                 return ERR_PTR(rc);
 651         }
 652
 653         /* can not grab the rename sem here since it would
 654         deadlock in the cases (beginning of sys_rename itself)
 655         in which we already have the sb rename sem */
 656         page = alloc_dentry_path();
 657         full_path = build_path_from_dentry(direntry, page);
 658         if (IS_ERR(full_path)) {
 659                 cifs_put_tlink(tlink);
 660                 free_xid(xid);
 661                 free_dentry_path(page);
 662                 return ERR_CAST(full_path);
 663         }
 664
 665         if (d_really_is_positive(direntry)) {
 666                 cifs_dbg(FYI, "non-NULL inode in lookup\n");
 667         } else {
 668                 cifs_dbg(FYI, "NULL inode in lookup\n");
 669         }
 670         cifs_dbg(FYI, "Full path: %s inode = 0x%p\n",
 671                  full_path, d_inode(direntry));
 672
 673 again:
 674         if (pTcon->posix_extensions)
 675                 rc = smb311_posix_get_inode_info(&newInode, full_path, parent_dir_inode->i_sb, xid);
 676         else if (pTcon->unix_ext) {
 677                 rc = cifs_get_inode_info_unix(&newInode, full_path,
 678                                               parent_dir_inode->i_sb, xid);
 679         } else {
 680                 rc = cifs_get_inode_info(&newInode, full_path, NULL,
 681                                 parent_dir_inode->i_sb, xid, NULL);
 682         }
 683
 684         if (rc == 0) {
 685                 /* since paths are not looked up by component - the parent
 686                    directories are presumed to be good here */
 687                 renew_parental_timestamps(direntry);
 688         } else if (rc == -EAGAIN && retry_count++ < 10) {
 689                 goto again;
 690         } else if (rc == -ENOENT) {
 691                 cifs_set_time(direntry, jiffies);
 692                 newInode = NULL;
 693         } else {
 694                 if (rc != -EACCES) {
 695                         cifs_dbg(FYI, "Unexpected lookup error %d\n", rc);
 696                         /* We special case check for Access Denied - since that
 697                         is a common return code */
 698                 }
 699                 newInode = ERR_PTR(rc);
 700         }
 701         free_dentry_path(page);
 702         cifs_put_tlink(tlink);
 703         free_xid(xid);
 704         return d_splice_alias(newInode, direntry);
 705 }
 706
 707 static int
 708 cifs_d_revalidate(struct dentry *direntry, unsigned int flags)
 709 {
 710         struct inode *inode;
 711         int rc;
 712
 713         if (flags & LOOKUP_RCU)
 714                 return -ECHILD;
 715
 716         if (d_really_is_positive(direntry)) {
 717                 inode = d_inode(direntry);
 718                 if ((flags & LOOKUP_REVAL) && !CIFS_CACHE_READ(CIFS_I(inode)))
 719                         CIFS_I(inode)->time = 0; /* force reval */
 720
 721                 rc = cifs_revalidate_dentry(direntry);
 722                 if (rc) {
 723                         cifs_dbg(FYI, "cifs_revalidate_dentry failed with rc=%d", rc);
 724                         switch (rc) {
 725                         case -ENOENT:
 726                         case -ESTALE:
 727                                 /*
 728                                  * Those errors mean the dentry is invalid
 729                                  * (file was deleted or recreated)
 730                                  */
 731                                 return 0;
 732                         default:
 733                                 /*
 734                                  * Otherwise some unexpected error happened
 735                                  * report it as-is to VFS layer
 736                                  */
 737                                 return rc;
 738                         }
 739                 }
 740                 else {
 741                         /*
 742                          * If the inode wasn't known to be a dfs entry when
 743                          * the dentry was instantiated, such as when created
 744                          * via ->readdir(), it needs to be set now since the
 745                          * attributes will have been updated by
 746                          * cifs_revalidate_dentry().
 747                          */
 748                         if (IS_AUTOMOUNT(inode) &&
 749                            !(direntry->d_flags & DCACHE_NEED_AUTOMOUNT)) {
 750                                 spin_lock(&direntry->d_lock);
 751                                 direntry->d_flags |= DCACHE_NEED_AUTOMOUNT;
 752                                 spin_unlock(&direntry->d_lock);
 753                         }
 754
 755                         return 1;
 756                 }
 757         }
 758
 759         /*
 760          * This may be nfsd (or something), anyway, we can't see the
 761          * intent of this. So, since this can be for creation, drop it.
 762          */
 763         if (!flags)
 764                 return 0;
 765
 766         /*
 767          * Drop the negative dentry, in order to make sure to use the
 768          * case sensitive name which is specified by user if this is
 769          * for creation.
 770          */
 771         if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))
 772                 return 0;
 773
 774         if (time_after(jiffies, cifs_get_time(direntry) + HZ) || !lookupCacheEnabled)
 775                 return 0;
 776
 777         return 1;
 778 }
 779
 780 /* static int cifs_d_delete(struct dentry *direntry)
 781 {
 782         int rc = 0;
 783
 784         cifs_dbg(FYI, "In cifs d_delete, name = %pd\n", direntry);
 785
 786         return rc;
 787 }     */
 788
 789 const struct dentry_operations cifs_dentry_ops = {
 790         .d_revalidate = cifs_d_revalidate,
 791         .d_automount = cifs_dfs_d_automount,
 792 /* d_delete:       cifs_d_delete,      */ /* not needed except for debugging */
 793 };
 794
 795 static int cifs_ci_hash(const struct dentry *dentry, struct qstr *q)
 796 {
 797         struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;
 798         unsigned long hash;
 799         wchar_t c;
 800         int i, charlen;
 801
 802         hash = init_name_hash(dentry);
 803         for (i = 0; i < q->len; i += charlen) {
 804                 charlen = codepage->char2uni(&q->name[i], q->len - i, &c);
 805                 /* error out if we can't convert the character */
 806                 if (unlikely(charlen < 0))
 807                         return charlen;
 808                 hash = partial_name_hash(cifs_toupper(c), hash);
 809         }
 810         q->hash = end_name_hash(hash);
 811
 812         return 0;
 813 }
 814
 815 static int cifs_ci_compare(const struct dentry *dentry,
 816                 unsigned int len, const char *str, const struct qstr *name)
 817 {
 818         struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;
 819         wchar_t c1, c2;
 820         int i, l1, l2;
 821
 822         /*
 823          * We make the assumption here that uppercase characters in the local
 824          * codepage are always the same length as their lowercase counterparts.
 825          *
 826          * If that's ever not the case, then this will fail to match it.
 827          */
 828         if (name->len != len)
 829                 return 1;
 830
 831         for (i = 0; i < len; i += l1) {
 832                 /* Convert characters in both strings to UTF-16. */
 833                 l1 = codepage->char2uni(&str[i], len - i, &c1);
 834                 l2 = codepage->char2uni(&name->name[i], name->len - i, &c2);
 835
 836                 /*
 837                  * If we can't convert either character, just declare it to
 838                  * be 1 byte long and compare the original byte.
 839                  */
 840                 if (unlikely(l1 < 0 && l2 < 0)) {
 841                         if (str[i] != name->name[i])
 842                                 return 1;
 843                         l1 = 1;
 844                         continue;
 845                 }
 846
 847                 /*
 848                  * Here, we again ass|u|me that upper/lowercase versions of
 849                  * a character are the same length in the local NLS.
 850                  */
 851                 if (l1 != l2)
 852                         return 1;
 853
 854                 /* Now compare uppercase versions of these characters */
 855                 if (cifs_toupper(c1) != cifs_toupper(c2))
 856                         return 1;
 857         }
 858
 859         return 0;
 860 }
 861
 862 const struct dentry_operations cifs_ci_dentry_ops = {
 863         .d_revalidate = cifs_d_revalidate,
 864         .d_hash = cifs_ci_hash,
 865         .d_compare = cifs_ci_compare,
 866         .d_automount = cifs_dfs_d_automount,
 867 };