fs/cifs/dir.c

   1 /*
   2  *   fs/cifs/dir.c
   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  *   This library is free software; you can redistribute it and/or modify
  10  *   it under the terms of the GNU Lesser General Public License as published
  11  *   by the Free Software Foundation; either version 2.1 of the License, or
  12  *   (at your option) any later version.
  13  *
  14  *   This library is distributed in the hope that it will be useful,
  15  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  17  *   the GNU Lesser General Public License for more details.
  18  *
  19  *   You should have received a copy of the GNU Lesser General Public License
  20  *   along with this library; if not, write to the Free Software
  21  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  22  */
  23 #include <linux/fs.h>
  24 #include <linux/stat.h>
  25 #include <linux/slab.h>
  26 #include <linux/namei.h>
  27 #include <linux/mount.h>
  28 #include <linux/file.h>
  29 #include "cifsfs.h"
  30 #include "cifspdu.h"
  31 #include "cifsglob.h"
  32 #include "cifsproto.h"
  33 #include "cifs_debug.h"
  34 #include "cifs_fs_sb.h"
  35 #include "cifs_unicode.h"
  36
  37 static void
  38 renew_parental_timestamps(struct dentry *direntry)
  39 {
  40         /* BB check if there is a way to get the kernel to do this or if we
  41            really need this */
  42         do {
  43                 cifs_set_time(direntry, jiffies);
  44                 direntry = direntry->d_parent;
  45         } while (!IS_ROOT(direntry));
  46 }
  47
  48 char *
  49 cifs_build_path_to_root(struct smb_vol *vol, struct cifs_sb_info *cifs_sb,
  50                         struct cifs_tcon *tcon, int add_treename)
  51 {
  52         int pplen = vol->prepath ? strlen(vol->prepath) + 1 : 0;
  53         int dfsplen;
  54         char *full_path = NULL;
  55
  56         /* if no prefix path, simply set path to the root of share to "" */
  57         if (pplen == 0) {
  58                 full_path = kzalloc(1, GFP_KERNEL);
  59                 return full_path;
  60         }
  61
  62         if (add_treename)
  63                 dfsplen = strnlen(tcon->treeName, MAX_TREE_SIZE + 1);
  64         else
  65                 dfsplen = 0;
  66
  67         full_path = kmalloc(dfsplen + pplen + 1, GFP_KERNEL);
  68         if (full_path == NULL)
  69                 return full_path;
  70
  71         if (dfsplen)
  72                 memcpy(full_path, tcon->treeName, dfsplen);
  73         full_path[dfsplen] = CIFS_DIR_SEP(cifs_sb);
  74         memcpy(full_path + dfsplen + 1, vol->prepath, pplen);
  75         convert_delimiter(full_path, CIFS_DIR_SEP(cifs_sb));
  76         return full_path;
  77 }
  78
  79 /* Note: caller must free return buffer */
  80 char *
  81 build_path_from_dentry(struct dentry *direntry)
  82 {
  83         struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
  84         struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
  85         bool prefix = tcon->Flags & SMB_SHARE_IS_IN_DFS;
  86
  87         return build_path_from_dentry_optional_prefix(direntry,
  88                                                       prefix);
  89 }
  90
  91 char *
  92 build_path_from_dentry_optional_prefix(struct dentry *direntry, bool prefix)
  93 {
  94         struct dentry *temp;
  95         int namelen;
  96         int dfsplen;
  97         int pplen = 0;
  98         char *full_path;
  99         char dirsep;
 100         struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
 101         struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
 102         unsigned seq;
 103
 104         dirsep = CIFS_DIR_SEP(cifs_sb);
 105         if (prefix)
 106                 dfsplen = strnlen(tcon->treeName, MAX_TREE_SIZE + 1);
 107         else
 108                 dfsplen = 0;
 109
 110         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH)
 111                 pplen = cifs_sb->prepath ? strlen(cifs_sb->prepath) + 1 : 0;
 112
 113 cifs_bp_rename_retry:
 114         namelen = dfsplen + pplen;
 115         seq = read_seqbegin(&rename_lock);
 116         rcu_read_lock();
 117         for (temp = direntry; !IS_ROOT(temp);) {
 118                 namelen += (1 + temp->d_name.len);
 119                 temp = temp->d_parent;
 120                 if (temp == NULL) {
 121                         cifs_dbg(VFS, "corrupt dentry\n");
 122                         rcu_read_unlock();
 123                         return NULL;
 124                 }
 125         }
 126         rcu_read_unlock();
 127
 128         full_path = kmalloc(namelen+1, GFP_ATOMIC);
 129         if (full_path == NULL)
 130                 return full_path;
 131         full_path[namelen] = 0; /* trailing null */
 132         rcu_read_lock();
 133         for (temp = direntry; !IS_ROOT(temp);) {
 134                 spin_lock(&temp->d_lock);
 135                 namelen -= 1 + temp->d_name.len;
 136                 if (namelen < 0) {
 137                         spin_unlock(&temp->d_lock);
 138                         break;
 139                 } else {
 140                         full_path[namelen] = dirsep;
 141                         strncpy(full_path + namelen + 1, temp->d_name.name,
 142                                 temp->d_name.len);
 143                         cifs_dbg(FYI, "name: %s\n", full_path + namelen);
 144                 }
 145                 spin_unlock(&temp->d_lock);
 146                 temp = temp->d_parent;
 147                 if (temp == NULL) {
 148                         cifs_dbg(VFS, "corrupt dentry\n");
 149                         rcu_read_unlock();
 150                         kfree(full_path);
 151                         return NULL;
 152                 }
 153         }
 154         rcu_read_unlock();
 155         if (namelen != dfsplen + pplen || read_seqretry(&rename_lock, seq)) {
 156                 cifs_dbg(FYI, "did not end path lookup where expected. namelen=%ddfsplen=%d\n",
 157                          namelen, dfsplen);
 158                 /* presumably this is only possible if racing with a rename
 159                 of one of the parent directories  (we can not lock the dentries
 160                 above us to prevent this, but retrying should be harmless) */
 161                 kfree(full_path);
 162                 goto cifs_bp_rename_retry;
 163         }
 164         /* DIR_SEP already set for byte  0 / vs \ but not for
 165            subsequent slashes in prepath which currently must
 166            be entered the right way - not sure if there is an alternative
 167            since the '\' is a valid posix character so we can not switch
 168            those safely to '/' if any are found in the middle of the prepath */
 169         /* BB test paths to Windows with '/' in the midst of prepath */
 170
 171         if (pplen) {
 172                 int i;
 173
 174                 cifs_dbg(FYI, "using cifs_sb prepath <%s>\n", cifs_sb->prepath);
 175                 memcpy(full_path+dfsplen+1, cifs_sb->prepath, pplen-1);
 176                 full_path[dfsplen] = dirsep;
 177                 for (i = 0; i < pplen-1; i++)
 178                         if (full_path[dfsplen+1+i] == '/')
 179                                 full_path[dfsplen+1+i] = CIFS_DIR_SEP(cifs_sb);
 180         }
 181
 182         if (dfsplen) {
 183                 strncpy(full_path, tcon->treeName, dfsplen);
 184                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS) {
 185                         int i;
 186                         for (i = 0; i < dfsplen; i++) {
 187                                 if (full_path[i] == '\\')
 188                                         full_path[i] = '/';
 189                         }
 190                 }
 191         }
 192         return full_path;
 193 }
 194
 195 /*
 196  * Don't allow path components longer than the server max.
 197  * Don't allow the separator character in a path component.
 198  * The VFS will not allow "/", but "\" is allowed by posix.
 199  */
 200 static int
 201 check_name(struct dentry *direntry, struct cifs_tcon *tcon)
 202 {
 203         struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
 204         int i;
 205
 206         if (unlikely(tcon->fsAttrInfo.MaxPathNameComponentLength &&
 207                      direntry->d_name.len >
 208                      le32_to_cpu(tcon->fsAttrInfo.MaxPathNameComponentLength)))
 209                 return -ENAMETOOLONG;
 210
 211         if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS)) {
 212                 for (i = 0; i < direntry->d_name.len; i++) {
 213                         if (direntry->d_name.name[i] == '\\') {
 214                                 cifs_dbg(FYI, "Invalid file name\n");
 215                                 return -EINVAL;
 216                         }
 217                 }
 218         }
 219         return 0;
 220 }
 221
 222
 223 /* Inode operations in similar order to how they appear in Linux file fs.h */
 224
 225 static int
 226 cifs_do_create(struct inode *inode, struct dentry *direntry, unsigned int xid,
 227                struct tcon_link *tlink, unsigned oflags, umode_t mode,
 228                __u32 *oplock, struct cifs_fid *fid)
 229 {
 230         int rc = -ENOENT;
 231         int create_options = CREATE_NOT_DIR;
 232         int desired_access;
 233         struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
 234         struct cifs_tcon *tcon = tlink_tcon(tlink);
 235         char *full_path = NULL;
 236         FILE_ALL_INFO *buf = NULL;
 237         struct inode *newinode = NULL;
 238         int disposition;
 239         struct TCP_Server_Info *server = tcon->ses->server;
 240         struct cifs_open_parms oparms;
 241
 242         *oplock = 0;
 243         if (tcon->ses->server->oplocks)
 244                 *oplock = REQ_OPLOCK;
 245
 246         full_path = build_path_from_dentry(direntry);
 247         if (full_path == NULL) {
 248                 rc = -ENOMEM;
 249                 goto out;
 250         }
 251
 252         if (tcon->unix_ext && cap_unix(tcon->ses) && !tcon->broken_posix_open &&
 253             (CIFS_UNIX_POSIX_PATH_OPS_CAP &
 254                         le64_to_cpu(tcon->fsUnixInfo.Capability))) {
 255                 rc = cifs_posix_open(full_path, &newinode, inode->i_sb, mode,
 256                                      oflags, oplock, &fid->netfid, xid);
 257                 switch (rc) {
 258                 case 0:
 259                         if (newinode == NULL) {
 260                                 /* query inode info */
 261                                 goto cifs_create_get_file_info;
 262                         }
 263
 264                         if (S_ISDIR(newinode->i_mode)) {
 265                                 CIFSSMBClose(xid, tcon, fid->netfid);
 266                                 iput(newinode);
 267                                 rc = -EISDIR;
 268                                 goto out;
 269                         }
 270
 271                         if (!S_ISREG(newinode->i_mode)) {
 272                                 /*
 273                                  * The server may allow us to open things like
 274                                  * FIFOs, but the client isn't set up to deal
 275                                  * with that. If it's not a regular file, just
 276                                  * close it and proceed as if it were a normal
 277                                  * lookup.
 278                                  */
 279                                 CIFSSMBClose(xid, tcon, fid->netfid);
 280                                 goto cifs_create_get_file_info;
 281                         }
 282                         /* success, no need to query */
 283                         goto cifs_create_set_dentry;
 284
 285                 case -ENOENT:
 286                         goto cifs_create_get_file_info;
 287
 288                 case -EIO:
 289                 case -EINVAL:
 290                         /*
 291                          * EIO could indicate that (posix open) operation is not
 292                          * supported, despite what server claimed in capability
 293                          * negotiation.
 294                          *
 295                          * POSIX open in samba versions 3.3.1 and earlier could
 296                          * incorrectly fail with invalid parameter.
 297                          */
 298                         tcon->broken_posix_open = true;
 299                         break;
 300
 301                 case -EREMOTE:
 302                 case -EOPNOTSUPP:
 303                         /*
 304                          * EREMOTE indicates DFS junction, which is not handled
 305                          * in posix open.  If either that or op not supported
 306                          * returned, follow the normal lookup.
 307                          */
 308                         break;
 309
 310                 default:
 311                         goto out;
 312                 }
 313                 /*
 314                  * fallthrough to retry, using older open call, this is case
 315                  * where server does not support this SMB level, and falsely
 316                  * claims capability (also get here for DFS case which should be
 317                  * rare for path not covered on files)
 318                  */
 319         }
 320
 321         desired_access = 0;
 322         if (OPEN_FMODE(oflags) & FMODE_READ)
 323                 desired_access |= GENERIC_READ; /* is this too little? */
 324         if (OPEN_FMODE(oflags) & FMODE_WRITE)
 325                 desired_access |= GENERIC_WRITE;
 326
 327         disposition = FILE_OVERWRITE_IF;
 328         if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
 329                 disposition = FILE_CREATE;
 330         else if ((oflags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))
 331                 disposition = FILE_OVERWRITE_IF;
 332         else if ((oflags & O_CREAT) == O_CREAT)
 333                 disposition = FILE_OPEN_IF;
 334         else
 335                 cifs_dbg(FYI, "Create flag not set in create function\n");
 336
 337         /*
 338          * BB add processing to set equivalent of mode - e.g. via CreateX with
 339          * ACLs
 340          */
 341
 342         if (!server->ops->open) {
 343                 rc = -ENOSYS;
 344                 goto out;
 345         }
 346
 347         buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
 348         if (buf == NULL) {
 349                 rc = -ENOMEM;
 350                 goto out;
 351         }
 352
 353         /*
 354          * if we're not using unix extensions, see if we need to set
 355          * ATTR_READONLY on the create call
 356          */
 357         if (!tcon->unix_ext && (mode & S_IWUGO) == 0)
 358                 create_options |= CREATE_OPTION_READONLY;
 359
 360         oparms.tcon = tcon;
 361         oparms.cifs_sb = cifs_sb;
 362         oparms.desired_access = desired_access;
 363         oparms.create_options = cifs_create_options(cifs_sb, create_options);
 364         oparms.disposition = disposition;
 365         oparms.path = full_path;
 366         oparms.fid = fid;
 367         oparms.reconnect = false;
 368         oparms.mode = mode;
 369         rc = server->ops->open(xid, &oparms, oplock, buf);
 370         if (rc) {
 371                 cifs_dbg(FYI, "cifs_create returned 0x%x\n", rc);
 372                 goto out;
 373         }
 374
 375         /*
 376          * If Open reported that we actually created a file then we now have to
 377          * set the mode if possible.
 378          */
 379         if ((tcon->unix_ext) && (*oplock & CIFS_CREATE_ACTION)) {
 380                 struct cifs_unix_set_info_args args = {
 381                                 .mode   = mode,
 382                                 .ctime  = NO_CHANGE_64,
 383                                 .atime  = NO_CHANGE_64,
 384                                 .mtime  = NO_CHANGE_64,
 385                                 .device = 0,
 386                 };
 387
 388                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
 389                         args.uid = current_fsuid();
 390                         if (inode->i_mode & S_ISGID)
 391                                 args.gid = inode->i_gid;
 392                         else
 393                                 args.gid = current_fsgid();
 394                 } else {
 395                         args.uid = INVALID_UID; /* no change */
 396                         args.gid = INVALID_GID; /* no change */
 397                 }
 398                 CIFSSMBUnixSetFileInfo(xid, tcon, &args, fid->netfid,
 399                                        current->tgid);
 400         } else {
 401                 /*
 402                  * BB implement mode setting via Windows security
 403                  * descriptors e.g.
 404                  */
 405                 /* CIFSSMBWinSetPerms(xid,tcon,path,mode,-1,-1,nls);*/
 406
 407                 /* Could set r/o dos attribute if mode & 0222 == 0 */
 408         }
 409
 410 cifs_create_get_file_info:
 411         /* server might mask mode so we have to query for it */
 412         if (tcon->unix_ext)
 413                 rc = cifs_get_inode_info_unix(&newinode, full_path, inode->i_sb,
 414                                               xid);
 415         else {
 416                 rc = cifs_get_inode_info(&newinode, full_path, buf, inode->i_sb,
 417                                          xid, fid);
 418                 if (newinode) {
 419                         if (server->ops->set_lease_key)
 420                                 server->ops->set_lease_key(newinode, fid);
 421                         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DYNPERM)
 422                                 newinode->i_mode = mode;
 423                         if ((*oplock & CIFS_CREATE_ACTION) &&
 424                             (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID)) {
 425                                 newinode->i_uid = current_fsuid();
 426                                 if (inode->i_mode & S_ISGID)
 427                                         newinode->i_gid = inode->i_gid;
 428                                 else
 429                                         newinode->i_gid = current_fsgid();
 430                         }
 431                 }
 432         }
 433
 434 cifs_create_set_dentry:
 435         if (rc != 0) {
 436                 cifs_dbg(FYI, "Create worked, get_inode_info failed rc = %d\n",
 437                          rc);
 438                 goto out_err;
 439         }
 440
 441         if (S_ISDIR(newinode->i_mode)) {
 442                 rc = -EISDIR;
 443                 goto out_err;
 444         }
 445
 446         d_drop(direntry);
 447         d_add(direntry, newinode);
 448
 449 out:
 450         kfree(buf);
 451         kfree(full_path);
 452         return rc;
 453
 454 out_err:
 455         if (server->ops->close)
 456                 server->ops->close(xid, tcon, fid);
 457         if (newinode)
 458                 iput(newinode);
 459         goto out;
 460 }
 461
 462 int
 463 cifs_atomic_open(struct inode *inode, struct dentry *direntry,
 464                  struct file *file, unsigned oflags, umode_t mode)
 465 {
 466         int rc;
 467         unsigned int xid;
 468         struct tcon_link *tlink;
 469         struct cifs_tcon *tcon;
 470         struct TCP_Server_Info *server;
 471         struct cifs_fid fid;
 472         struct cifs_pending_open open;
 473         __u32 oplock;
 474         struct cifsFileInfo *file_info;
 475
 476         /*
 477          * Posix open is only called (at lookup time) for file create now. For
 478          * opens (rather than creates), because we do not know if it is a file
 479          * or directory yet, and current Samba no longer allows us to do posix
 480          * open on dirs, we could end up wasting an open call on what turns out
 481          * to be a dir. For file opens, we wait to call posix open till
 482          * cifs_open.  It could be added to atomic_open in the future but the
 483          * performance tradeoff of the extra network request when EISDIR or
 484          * EACCES is returned would have to be weighed against the 50% reduction
 485          * in network traffic in the other paths.
 486          */
 487         if (!(oflags & O_CREAT)) {
 488                 struct dentry *res;
 489
 490                 /*
 491                  * Check for hashed negative dentry. We have already revalidated
 492                  * the dentry and it is fine. No need to perform another lookup.
 493                  */
 494                 if (!d_in_lookup(direntry))
 495                         return -ENOENT;
 496
 497                 res = cifs_lookup(inode, direntry, 0);
 498                 if (IS_ERR(res))
 499                         return PTR_ERR(res);
 500
 501                 return finish_no_open(file, res);
 502         }
 503
 504         xid = get_xid();
 505
 506         cifs_dbg(FYI, "parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
 507                  inode, direntry, direntry);
 508
 509         tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));
 510         if (IS_ERR(tlink)) {
 511                 rc = PTR_ERR(tlink);
 512                 goto out_free_xid;
 513         }
 514
 515         tcon = tlink_tcon(tlink);
 516
 517         rc = check_name(direntry, tcon);
 518         if (rc)
 519                 goto out;
 520
 521         server = tcon->ses->server;
 522
 523         if (server->ops->new_lease_key)
 524                 server->ops->new_lease_key(&fid);
 525
 526         cifs_add_pending_open(&fid, tlink, &open);
 527
 528         rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode,
 529                             &oplock, &fid);
 530
 531         if (rc) {
 532                 cifs_del_pending_open(&open);
 533                 goto out;
 534         }
 535
 536         if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
 537                 file->f_mode |= FMODE_CREATED;
 538
 539         rc = finish_open(file, direntry, generic_file_open);
 540         if (rc) {
 541                 if (server->ops->close)
 542                         server->ops->close(xid, tcon, &fid);
 543                 cifs_del_pending_open(&open);
 544                 goto out;
 545         }
 546
 547         if (file->f_flags & O_DIRECT &&
 548             CIFS_SB(inode->i_sb)->mnt_cifs_flags & CIFS_MOUNT_STRICT_IO) {
 549                 if (CIFS_SB(inode->i_sb)->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
 550                         file->f_op = &cifs_file_direct_nobrl_ops;
 551                 else
 552                         file->f_op = &cifs_file_direct_ops;
 553                 }
 554
 555         file_info = cifs_new_fileinfo(&fid, file, tlink, oplock);
 556         if (file_info == NULL) {
 557                 if (server->ops->close)
 558                         server->ops->close(xid, tcon, &fid);
 559                 cifs_del_pending_open(&open);
 560                 rc = -ENOMEM;
 561         }
 562
 563 out:
 564         cifs_put_tlink(tlink);
 565 out_free_xid:
 566         free_xid(xid);
 567         return rc;
 568 }
 569
 570 int cifs_create(struct inode *inode, struct dentry *direntry, umode_t mode,
 571                 bool excl)
 572 {
 573         int rc;
 574         unsigned int xid = get_xid();
 575         /*
 576          * BB below access is probably too much for mknod to request
 577          *    but we have to do query and setpathinfo so requesting
 578          *    less could fail (unless we want to request getatr and setatr
 579          *    permissions (only).  At least for POSIX we do not have to
 580          *    request so much.
 581          */
 582         unsigned oflags = O_EXCL | O_CREAT | O_RDWR;
 583         struct tcon_link *tlink;
 584         struct cifs_tcon *tcon;
 585         struct TCP_Server_Info *server;
 586         struct cifs_fid fid;
 587         __u32 oplock;
 588
 589         cifs_dbg(FYI, "cifs_create parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
 590                  inode, direntry, direntry);
 591
 592         tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));
 593         rc = PTR_ERR(tlink);
 594         if (IS_ERR(tlink))
 595                 goto out_free_xid;
 596
 597         tcon = tlink_tcon(tlink);
 598         server = tcon->ses->server;
 599
 600         if (server->ops->new_lease_key)
 601                 server->ops->new_lease_key(&fid);
 602
 603         rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode,
 604                             &oplock, &fid);
 605         if (!rc && server->ops->close)
 606                 server->ops->close(xid, tcon, &fid);
 607
 608         cifs_put_tlink(tlink);
 609 out_free_xid:
 610         free_xid(xid);
 611         return rc;
 612 }
 613
 614 int cifs_mknod(struct inode *inode, struct dentry *direntry, umode_t mode,
 615                 dev_t device_number)
 616 {
 617         int rc = -EPERM;
 618         unsigned int xid;
 619         struct cifs_sb_info *cifs_sb;
 620         struct tcon_link *tlink;
 621         struct cifs_tcon *tcon;
 622         char *full_path = NULL;
 623
 624         if (!old_valid_dev(device_number))
 625                 return -EINVAL;
 626
 627         cifs_sb = CIFS_SB(inode->i_sb);
 628         tlink = cifs_sb_tlink(cifs_sb);
 629         if (IS_ERR(tlink))
 630                 return PTR_ERR(tlink);
 631
 632         tcon = tlink_tcon(tlink);
 633
 634         xid = get_xid();
 635
 636         full_path = build_path_from_dentry(direntry);
 637         if (full_path == NULL) {
 638                 rc = -ENOMEM;
 639                 goto mknod_out;
 640         }
 641
 642         rc = tcon->ses->server->ops->make_node(xid, inode, direntry, tcon,
 643                                                full_path, mode,
 644                                                device_number);
 645
 646 mknod_out:
 647         kfree(full_path);
 648         free_xid(xid);
 649         cifs_put_tlink(tlink);
 650         return rc;
 651 }
 652
 653 struct dentry *
 654 cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,
 655             unsigned int flags)
 656 {
 657         unsigned int xid;
 658         int rc = 0; /* to get around spurious gcc warning, set to zero here */
 659         struct cifs_sb_info *cifs_sb;
 660         struct tcon_link *tlink;
 661         struct cifs_tcon *pTcon;
 662         struct inode *newInode = NULL;
 663         char *full_path = NULL;
 664
 665         xid = get_xid();
 666
 667         cifs_dbg(FYI, "parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
 668                  parent_dir_inode, direntry, direntry);
 669
 670         /* check whether path exists */
 671
 672         cifs_sb = CIFS_SB(parent_dir_inode->i_sb);
 673         tlink = cifs_sb_tlink(cifs_sb);
 674         if (IS_ERR(tlink)) {
 675                 free_xid(xid);
 676                 return ERR_CAST(tlink);
 677         }
 678         pTcon = tlink_tcon(tlink);
 679
 680         rc = check_name(direntry, pTcon);
 681         if (unlikely(rc)) {
 682                 cifs_put_tlink(tlink);
 683                 free_xid(xid);
 684                 return ERR_PTR(rc);
 685         }
 686
 687         /* can not grab the rename sem here since it would
 688         deadlock in the cases (beginning of sys_rename itself)
 689         in which we already have the sb rename sem */
 690         full_path = build_path_from_dentry(direntry);
 691         if (full_path == NULL) {
 692                 cifs_put_tlink(tlink);
 693                 free_xid(xid);
 694                 return ERR_PTR(-ENOMEM);
 695         }
 696
 697         if (d_really_is_positive(direntry)) {
 698                 cifs_dbg(FYI, "non-NULL inode in lookup\n");
 699         } else {
 700                 cifs_dbg(FYI, "NULL inode in lookup\n");
 701         }
 702         cifs_dbg(FYI, "Full path: %s inode = 0x%p\n",
 703                  full_path, d_inode(direntry));
 704
 705         if (pTcon->unix_ext) {
 706                 rc = cifs_get_inode_info_unix(&newInode, full_path,
 707                                               parent_dir_inode->i_sb, xid);
 708         } else {
 709                 rc = cifs_get_inode_info(&newInode, full_path, NULL,
 710                                 parent_dir_inode->i_sb, xid, NULL);
 711         }
 712
 713         if (rc == 0) {
 714                 /* since paths are not looked up by component - the parent
 715                    directories are presumed to be good here */
 716                 renew_parental_timestamps(direntry);
 717         } else if (rc == -ENOENT) {
 718                 cifs_set_time(direntry, jiffies);
 719                 newInode = NULL;
 720         } else {
 721                 if (rc != -EACCES) {
 722                         cifs_dbg(FYI, "Unexpected lookup error %d\n", rc);
 723                         /* We special case check for Access Denied - since that
 724                         is a common return code */
 725                 }
 726                 newInode = ERR_PTR(rc);
 727         }
 728         kfree(full_path);
 729         cifs_put_tlink(tlink);
 730         free_xid(xid);
 731         return d_splice_alias(newInode, direntry);
 732 }
 733
 734 static int
 735 cifs_d_revalidate(struct dentry *direntry, unsigned int flags)
 736 {
 737         struct inode *inode;
 738         int rc;
 739
 740         if (flags & LOOKUP_RCU)
 741                 return -ECHILD;
 742
 743         if (d_really_is_positive(direntry)) {
 744                 inode = d_inode(direntry);
 745                 if ((flags & LOOKUP_REVAL) && !CIFS_CACHE_READ(CIFS_I(inode)))
 746                         CIFS_I(inode)->time = 0; /* force reval */
 747
 748                 rc = cifs_revalidate_dentry(direntry);
 749                 if (rc) {
 750                         cifs_dbg(FYI, "cifs_revalidate_dentry failed with rc=%d", rc);
 751                         switch (rc) {
 752                         case -ENOENT:
 753                         case -ESTALE:
 754                                 /*
 755                                  * Those errors mean the dentry is invalid
 756                                  * (file was deleted or recreated)
 757                                  */
 758                                 return 0;
 759                         default:
 760                                 /*
 761                                  * Otherwise some unexpected error happened
 762                                  * report it as-is to VFS layer
 763                                  */
 764                                 return rc;
 765                         }
 766                 }
 767                 else {
 768                         /*
 769                          * If the inode wasn't known to be a dfs entry when
 770                          * the dentry was instantiated, such as when created
 771                          * via ->readdir(), it needs to be set now since the
 772                          * attributes will have been updated by
 773                          * cifs_revalidate_dentry().
 774                          */
 775                         if (IS_AUTOMOUNT(inode) &&
 776                            !(direntry->d_flags & DCACHE_NEED_AUTOMOUNT)) {
 777                                 spin_lock(&direntry->d_lock);
 778                                 direntry->d_flags |= DCACHE_NEED_AUTOMOUNT;
 779                                 spin_unlock(&direntry->d_lock);
 780                         }
 781
 782                         return 1;
 783                 }
 784         }
 785
 786         /*
 787          * This may be nfsd (or something), anyway, we can't see the
 788          * intent of this. So, since this can be for creation, drop it.
 789          */
 790         if (!flags)
 791                 return 0;
 792
 793         /*
 794          * Drop the negative dentry, in order to make sure to use the
 795          * case sensitive name which is specified by user if this is
 796          * for creation.
 797          */
 798         if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))
 799                 return 0;
 800
 801         if (time_after(jiffies, cifs_get_time(direntry) + HZ) || !lookupCacheEnabled)
 802                 return 0;
 803
 804         return 1;
 805 }
 806
 807 /* static int cifs_d_delete(struct dentry *direntry)
 808 {
 809         int rc = 0;
 810
 811         cifs_dbg(FYI, "In cifs d_delete, name = %pd\n", direntry);
 812
 813         return rc;
 814 }     */
 815
 816 const struct dentry_operations cifs_dentry_ops = {
 817         .d_revalidate = cifs_d_revalidate,
 818         .d_automount = cifs_dfs_d_automount,
 819 /* d_delete:       cifs_d_delete,      */ /* not needed except for debugging */
 820 };
 821
 822 static int cifs_ci_hash(const struct dentry *dentry, struct qstr *q)
 823 {
 824         struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;
 825         unsigned long hash;
 826         wchar_t c;
 827         int i, charlen;
 828
 829         hash = init_name_hash(dentry);
 830         for (i = 0; i < q->len; i += charlen) {
 831                 charlen = codepage->char2uni(&q->name[i], q->len - i, &c);
 832                 /* error out if we can't convert the character */
 833                 if (unlikely(charlen < 0))
 834                         return charlen;
 835                 hash = partial_name_hash(cifs_toupper(c), hash);
 836         }
 837         q->hash = end_name_hash(hash);
 838
 839         return 0;
 840 }
 841
 842 static int cifs_ci_compare(const struct dentry *dentry,
 843                 unsigned int len, const char *str, const struct qstr *name)
 844 {
 845         struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;
 846         wchar_t c1, c2;
 847         int i, l1, l2;
 848
 849         /*
 850          * We make the assumption here that uppercase characters in the local
 851          * codepage are always the same length as their lowercase counterparts.
 852          *
 853          * If that's ever not the case, then this will fail to match it.
 854          */
 855         if (name->len != len)
 856                 return 1;
 857
 858         for (i = 0; i < len; i += l1) {
 859                 /* Convert characters in both strings to UTF-16. */
 860                 l1 = codepage->char2uni(&str[i], len - i, &c1);
 861                 l2 = codepage->char2uni(&name->name[i], name->len - i, &c2);
 862
 863                 /*
 864                  * If we can't convert either character, just declare it to
 865                  * be 1 byte long and compare the original byte.
 866                  */
 867                 if (unlikely(l1 < 0 && l2 < 0)) {
 868                         if (str[i] != name->name[i])
 869                                 return 1;
 870                         l1 = 1;
 871                         continue;
 872                 }
 873
 874                 /*
 875                  * Here, we again ass|u|me that upper/lowercase versions of
 876                  * a character are the same length in the local NLS.
 877                  */
 878                 if (l1 != l2)
 879                         return 1;
 880
 881                 /* Now compare uppercase versions of these characters */
 882                 if (cifs_toupper(c1) != cifs_toupper(c2))
 883                         return 1;
 884         }
 885
 886         return 0;
 887 }
 888
 889 const struct dentry_operations cifs_ci_dentry_ops = {
 890         .d_revalidate = cifs_d_revalidate,
 891         .d_hash = cifs_ci_hash,
 892         .d_compare = cifs_ci_compare,
 893         .d_automount = cifs_dfs_d_automount,
 894 };