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                 direntry->d_time = 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)
  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 (tcon->Flags & SMB_SHARE_IS_IN_DFS)
  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                 strncpy(full_path, tcon->treeName, dfsplen);
  73         full_path[dfsplen] = CIFS_DIR_SEP(cifs_sb);
  74         strncpy(full_path + dfsplen + 1, vol->prepath, pplen);
  75         convert_delimiter(full_path, CIFS_DIR_SEP(cifs_sb));
  76         full_path[dfsplen + pplen] = 0; /* add trailing null */
  77         return full_path;
  78 }
  79
  80 /* Note: caller must free return buffer */
  81 char *
  82 build_path_from_dentry(struct dentry *direntry)
  83 {
  84         struct dentry *temp;
  85         int namelen;
  86         int dfsplen;
  87         char *full_path;
  88         char dirsep;
  89         struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
  90         struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
  91         unsigned seq;
  92
  93         dirsep = CIFS_DIR_SEP(cifs_sb);
  94         if (tcon->Flags & SMB_SHARE_IS_IN_DFS)
  95                 dfsplen = strnlen(tcon->treeName, MAX_TREE_SIZE + 1);
  96         else
  97                 dfsplen = 0;
  98 cifs_bp_rename_retry:
  99         namelen = dfsplen;
 100         seq = read_seqbegin(&rename_lock);
 101         rcu_read_lock();
 102         for (temp = direntry; !IS_ROOT(temp);) {
 103                 namelen += (1 + temp->d_name.len);
 104                 temp = temp->d_parent;
 105                 if (temp == NULL) {
 106                         cifs_dbg(VFS, "corrupt dentry\n");
 107                         rcu_read_unlock();
 108                         return NULL;
 109                 }
 110         }
 111         rcu_read_unlock();
 112
 113         full_path = kmalloc(namelen+1, GFP_KERNEL);
 114         if (full_path == NULL)
 115                 return full_path;
 116         full_path[namelen] = 0; /* trailing null */
 117         rcu_read_lock();
 118         for (temp = direntry; !IS_ROOT(temp);) {
 119                 spin_lock(&temp->d_lock);
 120                 namelen -= 1 + temp->d_name.len;
 121                 if (namelen < 0) {
 122                         spin_unlock(&temp->d_lock);
 123                         break;
 124                 } else {
 125                         full_path[namelen] = dirsep;
 126                         strncpy(full_path + namelen + 1, temp->d_name.name,
 127                                 temp->d_name.len);
 128                         cifs_dbg(FYI, "name: %s\n", full_path + namelen);
 129                 }
 130                 spin_unlock(&temp->d_lock);
 131                 temp = temp->d_parent;
 132                 if (temp == NULL) {
 133                         cifs_dbg(VFS, "corrupt dentry\n");
 134                         rcu_read_unlock();
 135                         kfree(full_path);
 136                         return NULL;
 137                 }
 138         }
 139         rcu_read_unlock();
 140         if (namelen != dfsplen || read_seqretry(&rename_lock, seq)) {
 141                 cifs_dbg(FYI, "did not end path lookup where expected. namelen=%ddfsplen=%d\n",
 142                          namelen, dfsplen);
 143                 /* presumably this is only possible if racing with a rename
 144                 of one of the parent directories  (we can not lock the dentries
 145                 above us to prevent this, but retrying should be harmless) */
 146                 kfree(full_path);
 147                 goto cifs_bp_rename_retry;
 148         }
 149         /* DIR_SEP already set for byte  0 / vs \ but not for
 150            subsequent slashes in prepath which currently must
 151            be entered the right way - not sure if there is an alternative
 152            since the '\' is a valid posix character so we can not switch
 153            those safely to '/' if any are found in the middle of the prepath */
 154         /* BB test paths to Windows with '/' in the midst of prepath */
 155
 156         if (dfsplen) {
 157                 strncpy(full_path, tcon->treeName, dfsplen);
 158                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS) {
 159                         int i;
 160                         for (i = 0; i < dfsplen; i++) {
 161                                 if (full_path[i] == '\\')
 162                                         full_path[i] = '/';
 163                         }
 164                 }
 165         }
 166         return full_path;
 167 }
 168
 169 /*
 170  * Don't allow the separator character in a path component.
 171  * The VFS will not allow "/", but "\" is allowed by posix.
 172  */
 173 static int
 174 check_name(struct dentry *direntry)
 175 {
 176         struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
 177         int i;
 178
 179         if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS)) {
 180                 for (i = 0; i < direntry->d_name.len; i++) {
 181                         if (direntry->d_name.name[i] == '\\') {
 182                                 cifs_dbg(FYI, "Invalid file name\n");
 183                                 return -EINVAL;
 184                         }
 185                 }
 186         }
 187         return 0;
 188 }
 189
 190
 191 /* Inode operations in similar order to how they appear in Linux file fs.h */
 192
 193 static int
 194 cifs_do_create(struct inode *inode, struct dentry *direntry, unsigned int xid,
 195                struct tcon_link *tlink, unsigned oflags, umode_t mode,
 196                __u32 *oplock, struct cifs_fid *fid, int *created)
 197 {
 198         int rc = -ENOENT;
 199         int create_options = CREATE_NOT_DIR;
 200         int desired_access;
 201         struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
 202         struct cifs_tcon *tcon = tlink_tcon(tlink);
 203         char *full_path = NULL;
 204         FILE_ALL_INFO *buf = NULL;
 205         struct inode *newinode = NULL;
 206         int disposition;
 207         struct TCP_Server_Info *server = tcon->ses->server;
 208         struct cifs_open_parms oparms;
 209
 210         *oplock = 0;
 211         if (tcon->ses->server->oplocks)
 212                 *oplock = REQ_OPLOCK;
 213
 214         full_path = build_path_from_dentry(direntry);
 215         if (full_path == NULL) {
 216                 rc = -ENOMEM;
 217                 goto out;
 218         }
 219
 220         if (tcon->unix_ext && cap_unix(tcon->ses) && !tcon->broken_posix_open &&
 221             (CIFS_UNIX_POSIX_PATH_OPS_CAP &
 222                         le64_to_cpu(tcon->fsUnixInfo.Capability))) {
 223                 rc = cifs_posix_open(full_path, &newinode, inode->i_sb, mode,
 224                                      oflags, oplock, &fid->netfid, xid);
 225                 switch (rc) {
 226                 case 0:
 227                         if (newinode == NULL) {
 228                                 /* query inode info */
 229                                 goto cifs_create_get_file_info;
 230                         }
 231
 232                         if (!S_ISREG(newinode->i_mode)) {
 233                                 /*
 234                                  * The server may allow us to open things like
 235                                  * FIFOs, but the client isn't set up to deal
 236                                  * with that. If it's not a regular file, just
 237                                  * close it and proceed as if it were a normal
 238                                  * lookup.
 239                                  */
 240                                 CIFSSMBClose(xid, tcon, fid->netfid);
 241                                 goto cifs_create_get_file_info;
 242                         }
 243                         /* success, no need to query */
 244                         goto cifs_create_set_dentry;
 245
 246                 case -ENOENT:
 247                         goto cifs_create_get_file_info;
 248
 249                 case -EIO:
 250                 case -EINVAL:
 251                         /*
 252                          * EIO could indicate that (posix open) operation is not
 253                          * supported, despite what server claimed in capability
 254                          * negotiation.
 255                          *
 256                          * POSIX open in samba versions 3.3.1 and earlier could
 257                          * incorrectly fail with invalid parameter.
 258                          */
 259                         tcon->broken_posix_open = true;
 260                         break;
 261
 262                 case -EREMOTE:
 263                 case -EOPNOTSUPP:
 264                         /*
 265                          * EREMOTE indicates DFS junction, which is not handled
 266                          * in posix open.  If either that or op not supported
 267                          * returned, follow the normal lookup.
 268                          */
 269                         break;
 270
 271                 default:
 272                         goto out;
 273                 }
 274                 /*
 275                  * fallthrough to retry, using older open call, this is case
 276                  * where server does not support this SMB level, and falsely
 277                  * claims capability (also get here for DFS case which should be
 278                  * rare for path not covered on files)
 279                  */
 280         }
 281
 282         desired_access = 0;
 283         if (OPEN_FMODE(oflags) & FMODE_READ)
 284                 desired_access |= GENERIC_READ; /* is this too little? */
 285         if (OPEN_FMODE(oflags) & FMODE_WRITE)
 286                 desired_access |= GENERIC_WRITE;
 287
 288         disposition = FILE_OVERWRITE_IF;
 289         if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
 290                 disposition = FILE_CREATE;
 291         else if ((oflags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))
 292                 disposition = FILE_OVERWRITE_IF;
 293         else if ((oflags & O_CREAT) == O_CREAT)
 294                 disposition = FILE_OPEN_IF;
 295         else
 296                 cifs_dbg(FYI, "Create flag not set in create function\n");
 297
 298         /*
 299          * BB add processing to set equivalent of mode - e.g. via CreateX with
 300          * ACLs
 301          */
 302
 303         if (!server->ops->open) {
 304                 rc = -ENOSYS;
 305                 goto out;
 306         }
 307
 308         buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
 309         if (buf == NULL) {
 310                 rc = -ENOMEM;
 311                 goto out;
 312         }
 313
 314         /*
 315          * if we're not using unix extensions, see if we need to set
 316          * ATTR_READONLY on the create call
 317          */
 318         if (!tcon->unix_ext && (mode & S_IWUGO) == 0)
 319                 create_options |= CREATE_OPTION_READONLY;
 320
 321         if (backup_cred(cifs_sb))
 322                 create_options |= CREATE_OPEN_BACKUP_INTENT;
 323
 324         oparms.tcon = tcon;
 325         oparms.cifs_sb = cifs_sb;
 326         oparms.desired_access = desired_access;
 327         oparms.create_options = create_options;
 328         oparms.disposition = disposition;
 329         oparms.path = full_path;
 330         oparms.fid = fid;
 331         oparms.reconnect = false;
 332
 333         rc = server->ops->open(xid, &oparms, oplock, buf);
 334         if (rc) {
 335                 cifs_dbg(FYI, "cifs_create returned 0x%x\n", rc);
 336                 goto out;
 337         }
 338
 339         /*
 340          * If Open reported that we actually created a file then we now have to
 341          * set the mode if possible.
 342          */
 343         if ((tcon->unix_ext) && (*oplock & CIFS_CREATE_ACTION)) {
 344                 struct cifs_unix_set_info_args args = {
 345                                 .mode   = mode,
 346                                 .ctime  = NO_CHANGE_64,
 347                                 .atime  = NO_CHANGE_64,
 348                                 .mtime  = NO_CHANGE_64,
 349                                 .device = 0,
 350                 };
 351
 352                 *created |= FILE_CREATED;
 353                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
 354                         args.uid = current_fsuid();
 355                         if (inode->i_mode & S_ISGID)
 356                                 args.gid = inode->i_gid;
 357                         else
 358                                 args.gid = current_fsgid();
 359                 } else {
 360                         args.uid = INVALID_UID; /* no change */
 361                         args.gid = INVALID_GID; /* no change */
 362                 }
 363                 CIFSSMBUnixSetFileInfo(xid, tcon, &args, fid->netfid,
 364                                        current->tgid);
 365         } else {
 366                 /*
 367                  * BB implement mode setting via Windows security
 368                  * descriptors e.g.
 369                  */
 370                 /* CIFSSMBWinSetPerms(xid,tcon,path,mode,-1,-1,nls);*/
 371
 372                 /* Could set r/o dos attribute if mode & 0222 == 0 */
 373         }
 374
 375 cifs_create_get_file_info:
 376         /* server might mask mode so we have to query for it */
 377         if (tcon->unix_ext)
 378                 rc = cifs_get_inode_info_unix(&newinode, full_path, inode->i_sb,
 379                                               xid);
 380         else {
 381                 rc = cifs_get_inode_info(&newinode, full_path, buf, inode->i_sb,
 382                                          xid, &fid->netfid);
 383                 if (newinode) {
 384                         if (server->ops->set_lease_key)
 385                                 server->ops->set_lease_key(newinode, fid);
 386                         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DYNPERM)
 387                                 newinode->i_mode = mode;
 388                         if ((*oplock & CIFS_CREATE_ACTION) &&
 389                             (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID)) {
 390                                 newinode->i_uid = current_fsuid();
 391                                 if (inode->i_mode & S_ISGID)
 392                                         newinode->i_gid = inode->i_gid;
 393                                 else
 394                                         newinode->i_gid = current_fsgid();
 395                         }
 396                 }
 397         }
 398
 399 cifs_create_set_dentry:
 400         if (rc != 0) {
 401                 cifs_dbg(FYI, "Create worked, get_inode_info failed rc = %d\n",
 402                          rc);
 403                 if (server->ops->close)
 404                         server->ops->close(xid, tcon, fid);
 405                 goto out;
 406         }
 407         d_drop(direntry);
 408         d_add(direntry, newinode);
 409
 410 out:
 411         kfree(buf);
 412         kfree(full_path);
 413         return rc;
 414 }
 415
 416 int
 417 cifs_atomic_open(struct inode *inode, struct dentry *direntry,
 418                  struct file *file, unsigned oflags, umode_t mode,
 419                  int *opened)
 420 {
 421         int rc;
 422         unsigned int xid;
 423         struct tcon_link *tlink;
 424         struct cifs_tcon *tcon;
 425         struct TCP_Server_Info *server;
 426         struct cifs_fid fid;
 427         struct cifs_pending_open open;
 428         __u32 oplock;
 429         struct cifsFileInfo *file_info;
 430
 431         /*
 432          * Posix open is only called (at lookup time) for file create now. For
 433          * opens (rather than creates), because we do not know if it is a file
 434          * or directory yet, and current Samba no longer allows us to do posix
 435          * open on dirs, we could end up wasting an open call on what turns out
 436          * to be a dir. For file opens, we wait to call posix open till
 437          * cifs_open.  It could be added to atomic_open in the future but the
 438          * performance tradeoff of the extra network request when EISDIR or
 439          * EACCES is returned would have to be weighed against the 50% reduction
 440          * in network traffic in the other paths.
 441          */
 442         if (!(oflags & O_CREAT)) {
 443                 struct dentry *res;
 444
 445                 /*
 446                  * Check for hashed negative dentry. We have already revalidated
 447                  * the dentry and it is fine. No need to perform another lookup.
 448                  */
 449                 if (!d_unhashed(direntry))
 450                         return -ENOENT;
 451
 452                 res = cifs_lookup(inode, direntry, 0);
 453                 if (IS_ERR(res))
 454                         return PTR_ERR(res);
 455
 456                 return finish_no_open(file, res);
 457         }
 458
 459         rc = check_name(direntry);
 460         if (rc)
 461                 return rc;
 462
 463         xid = get_xid();
 464
 465         cifs_dbg(FYI, "parent inode = 0x%p name is: %s and dentry = 0x%p\n",
 466                  inode, direntry->d_name.name, direntry);
 467
 468         tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));
 469         if (IS_ERR(tlink)) {
 470                 rc = PTR_ERR(tlink);
 471                 goto out_free_xid;
 472         }
 473
 474         tcon = tlink_tcon(tlink);
 475         server = tcon->ses->server;
 476
 477         if (server->ops->new_lease_key)
 478                 server->ops->new_lease_key(&fid);
 479
 480         cifs_add_pending_open(&fid, tlink, &open);
 481
 482         rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode,
 483                             &oplock, &fid, opened);
 484
 485         if (rc) {
 486                 cifs_del_pending_open(&open);
 487                 goto out;
 488         }
 489
 490         rc = finish_open(file, direntry, generic_file_open, opened);
 491         if (rc) {
 492                 if (server->ops->close)
 493                         server->ops->close(xid, tcon, &fid);
 494                 cifs_del_pending_open(&open);
 495                 goto out;
 496         }
 497
 498         file_info = cifs_new_fileinfo(&fid, file, tlink, oplock);
 499         if (file_info == NULL) {
 500                 if (server->ops->close)
 501                         server->ops->close(xid, tcon, &fid);
 502                 cifs_del_pending_open(&open);
 503                 fput(file);
 504                 rc = -ENOMEM;
 505         }
 506
 507 out:
 508         cifs_put_tlink(tlink);
 509 out_free_xid:
 510         free_xid(xid);
 511         return rc;
 512 }
 513
 514 int cifs_create(struct inode *inode, struct dentry *direntry, umode_t mode,
 515                 bool excl)
 516 {
 517         int rc;
 518         unsigned int xid = get_xid();
 519         /*
 520          * BB below access is probably too much for mknod to request
 521          *    but we have to do query and setpathinfo so requesting
 522          *    less could fail (unless we want to request getatr and setatr
 523          *    permissions (only).  At least for POSIX we do not have to
 524          *    request so much.
 525          */
 526         unsigned oflags = O_EXCL | O_CREAT | O_RDWR;
 527         struct tcon_link *tlink;
 528         struct cifs_tcon *tcon;
 529         struct TCP_Server_Info *server;
 530         struct cifs_fid fid;
 531         __u32 oplock;
 532         int created = FILE_CREATED;
 533
 534         cifs_dbg(FYI, "cifs_create parent inode = 0x%p name is: %s and dentry = 0x%p\n",
 535                  inode, direntry->d_name.name, direntry);
 536
 537         tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));
 538         rc = PTR_ERR(tlink);
 539         if (IS_ERR(tlink))
 540                 goto out_free_xid;
 541
 542         tcon = tlink_tcon(tlink);
 543         server = tcon->ses->server;
 544
 545         if (server->ops->new_lease_key)
 546                 server->ops->new_lease_key(&fid);
 547
 548         rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode,
 549                             &oplock, &fid, &created);
 550         if (!rc && server->ops->close)
 551                 server->ops->close(xid, tcon, &fid);
 552
 553         cifs_put_tlink(tlink);
 554 out_free_xid:
 555         free_xid(xid);
 556         return rc;
 557 }
 558
 559 int cifs_mknod(struct inode *inode, struct dentry *direntry, umode_t mode,
 560                 dev_t device_number)
 561 {
 562         int rc = -EPERM;
 563         unsigned int xid;
 564         int create_options = CREATE_NOT_DIR | CREATE_OPTION_SPECIAL;
 565         struct cifs_sb_info *cifs_sb;
 566         struct tcon_link *tlink;
 567         struct cifs_tcon *pTcon;
 568         struct cifs_io_parms io_parms;
 569         char *full_path = NULL;
 570         struct inode *newinode = NULL;
 571         int oplock = 0;
 572         u16 fileHandle;
 573         FILE_ALL_INFO *buf = NULL;
 574         unsigned int bytes_written;
 575         struct win_dev *pdev;
 576
 577         if (!old_valid_dev(device_number))
 578                 return -EINVAL;
 579
 580         cifs_sb = CIFS_SB(inode->i_sb);
 581         tlink = cifs_sb_tlink(cifs_sb);
 582         if (IS_ERR(tlink))
 583                 return PTR_ERR(tlink);
 584
 585         pTcon = tlink_tcon(tlink);
 586
 587         xid = get_xid();
 588
 589         full_path = build_path_from_dentry(direntry);
 590         if (full_path == NULL) {
 591                 rc = -ENOMEM;
 592                 goto mknod_out;
 593         }
 594
 595         if (pTcon->unix_ext) {
 596                 struct cifs_unix_set_info_args args = {
 597                         .mode   = mode & ~current_umask(),
 598                         .ctime  = NO_CHANGE_64,
 599                         .atime  = NO_CHANGE_64,
 600                         .mtime  = NO_CHANGE_64,
 601                         .device = device_number,
 602                 };
 603                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
 604                         args.uid = current_fsuid();
 605                         args.gid = current_fsgid();
 606                 } else {
 607                         args.uid = INVALID_UID; /* no change */
 608                         args.gid = INVALID_GID; /* no change */
 609                 }
 610                 rc = CIFSSMBUnixSetPathInfo(xid, pTcon, full_path, &args,
 611                                             cifs_sb->local_nls,
 612                                             cifs_sb->mnt_cifs_flags &
 613                                                 CIFS_MOUNT_MAP_SPECIAL_CHR);
 614                 if (rc)
 615                         goto mknod_out;
 616
 617                 rc = cifs_get_inode_info_unix(&newinode, full_path,
 618                                                 inode->i_sb, xid);
 619
 620                 if (rc == 0)
 621                         d_instantiate(direntry, newinode);
 622                 goto mknod_out;
 623         }
 624
 625         if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL))
 626                 goto mknod_out;
 627
 628
 629         cifs_dbg(FYI, "sfu compat create special file\n");
 630
 631         buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
 632         if (buf == NULL) {
 633                 kfree(full_path);
 634                 rc = -ENOMEM;
 635                 free_xid(xid);
 636                 return rc;
 637         }
 638
 639         if (backup_cred(cifs_sb))
 640                 create_options |= CREATE_OPEN_BACKUP_INTENT;
 641
 642         rc = CIFSSMBOpen(xid, pTcon, full_path, FILE_CREATE,
 643                          GENERIC_WRITE, create_options,
 644                          &fileHandle, &oplock, buf, cifs_sb->local_nls,
 645                          cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
 646         if (rc)
 647                 goto mknod_out;
 648
 649         /* BB Do not bother to decode buf since no local inode yet to put
 650          * timestamps in, but we can reuse it safely */
 651
 652         pdev = (struct win_dev *)buf;
 653         io_parms.netfid = fileHandle;
 654         io_parms.pid = current->tgid;
 655         io_parms.tcon = pTcon;
 656         io_parms.offset = 0;
 657         io_parms.length = sizeof(struct win_dev);
 658         if (S_ISCHR(mode)) {
 659                 memcpy(pdev->type, "IntxCHR", 8);
 660                 pdev->major =
 661                       cpu_to_le64(MAJOR(device_number));
 662                 pdev->minor =
 663                       cpu_to_le64(MINOR(device_number));
 664                 rc = CIFSSMBWrite(xid, &io_parms,
 665                         &bytes_written, (char *)pdev,
 666                         NULL, 0);
 667         } else if (S_ISBLK(mode)) {
 668                 memcpy(pdev->type, "IntxBLK", 8);
 669                 pdev->major =
 670                       cpu_to_le64(MAJOR(device_number));
 671                 pdev->minor =
 672                       cpu_to_le64(MINOR(device_number));
 673                 rc = CIFSSMBWrite(xid, &io_parms,
 674                         &bytes_written, (char *)pdev,
 675                         NULL, 0);
 676         } /* else if (S_ISFIFO) */
 677         CIFSSMBClose(xid, pTcon, fileHandle);
 678         d_drop(direntry);
 679
 680         /* FIXME: add code here to set EAs */
 681
 682 mknod_out:
 683         kfree(full_path);
 684         kfree(buf);
 685         free_xid(xid);
 686         cifs_put_tlink(tlink);
 687         return rc;
 688 }
 689
 690 struct dentry *
 691 cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,
 692             unsigned int flags)
 693 {
 694         unsigned int xid;
 695         int rc = 0; /* to get around spurious gcc warning, set to zero here */
 696         struct cifs_sb_info *cifs_sb;
 697         struct tcon_link *tlink;
 698         struct cifs_tcon *pTcon;
 699         struct inode *newInode = NULL;
 700         char *full_path = NULL;
 701
 702         xid = get_xid();
 703
 704         cifs_dbg(FYI, "parent inode = 0x%p name is: %s and dentry = 0x%p\n",
 705                  parent_dir_inode, direntry->d_name.name, direntry);
 706
 707         /* check whether path exists */
 708
 709         cifs_sb = CIFS_SB(parent_dir_inode->i_sb);
 710         tlink = cifs_sb_tlink(cifs_sb);
 711         if (IS_ERR(tlink)) {
 712                 free_xid(xid);
 713                 return (struct dentry *)tlink;
 714         }
 715         pTcon = tlink_tcon(tlink);
 716
 717         rc = check_name(direntry);
 718         if (rc)
 719                 goto lookup_out;
 720
 721         /* can not grab the rename sem here since it would
 722         deadlock in the cases (beginning of sys_rename itself)
 723         in which we already have the sb rename sem */
 724         full_path = build_path_from_dentry(direntry);
 725         if (full_path == NULL) {
 726                 rc = -ENOMEM;
 727                 goto lookup_out;
 728         }
 729
 730         if (direntry->d_inode != NULL) {
 731                 cifs_dbg(FYI, "non-NULL inode in lookup\n");
 732         } else {
 733                 cifs_dbg(FYI, "NULL inode in lookup\n");
 734         }
 735         cifs_dbg(FYI, "Full path: %s inode = 0x%p\n",
 736                  full_path, direntry->d_inode);
 737
 738         if (pTcon->unix_ext) {
 739                 rc = cifs_get_inode_info_unix(&newInode, full_path,
 740                                               parent_dir_inode->i_sb, xid);
 741         } else {
 742                 rc = cifs_get_inode_info(&newInode, full_path, NULL,
 743                                 parent_dir_inode->i_sb, xid, NULL);
 744         }
 745
 746         if ((rc == 0) && (newInode != NULL)) {
 747                 d_add(direntry, newInode);
 748                 /* since paths are not looked up by component - the parent
 749                    directories are presumed to be good here */
 750                 renew_parental_timestamps(direntry);
 751
 752         } else if (rc == -ENOENT) {
 753                 rc = 0;
 754                 direntry->d_time = jiffies;
 755                 d_add(direntry, NULL);
 756         /*      if it was once a directory (but how can we tell?) we could do
 757                 shrink_dcache_parent(direntry); */
 758         } else if (rc != -EACCES) {
 759                 cifs_dbg(VFS, "Unexpected lookup error %d\n", rc);
 760                 /* We special case check for Access Denied - since that
 761                 is a common return code */
 762         }
 763
 764 lookup_out:
 765         kfree(full_path);
 766         cifs_put_tlink(tlink);
 767         free_xid(xid);
 768         return ERR_PTR(rc);
 769 }
 770
 771 static int
 772 cifs_d_revalidate(struct dentry *direntry, unsigned int flags)
 773 {
 774         if (flags & LOOKUP_RCU)
 775                 return -ECHILD;
 776
 777         if (direntry->d_inode) {
 778                 if (cifs_revalidate_dentry(direntry))
 779                         return 0;
 780                 else {
 781                         /*
 782                          * If the inode wasn't known to be a dfs entry when
 783                          * the dentry was instantiated, such as when created
 784                          * via ->readdir(), it needs to be set now since the
 785                          * attributes will have been updated by
 786                          * cifs_revalidate_dentry().
 787                          */
 788                         if (IS_AUTOMOUNT(direntry->d_inode) &&
 789                            !(direntry->d_flags & DCACHE_NEED_AUTOMOUNT)) {
 790                                 spin_lock(&direntry->d_lock);
 791                                 direntry->d_flags |= DCACHE_NEED_AUTOMOUNT;
 792                                 spin_unlock(&direntry->d_lock);
 793                         }
 794
 795                         return 1;
 796                 }
 797         }
 798
 799         /*
 800          * This may be nfsd (or something), anyway, we can't see the
 801          * intent of this. So, since this can be for creation, drop it.
 802          */
 803         if (!flags)
 804                 return 0;
 805
 806         /*
 807          * Drop the negative dentry, in order to make sure to use the
 808          * case sensitive name which is specified by user if this is
 809          * for creation.
 810          */
 811         if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))
 812                 return 0;
 813
 814         if (time_after(jiffies, direntry->d_time + HZ) || !lookupCacheEnabled)
 815                 return 0;
 816
 817         return 1;
 818 }
 819
 820 /* static int cifs_d_delete(struct dentry *direntry)
 821 {
 822         int rc = 0;
 823
 824         cifs_dbg(FYI, "In cifs d_delete, name = %s\n", direntry->d_name.name);
 825
 826         return rc;
 827 }     */
 828
 829 const struct dentry_operations cifs_dentry_ops = {
 830         .d_revalidate = cifs_d_revalidate,
 831         .d_automount = cifs_dfs_d_automount,
 832 /* d_delete:       cifs_d_delete,      */ /* not needed except for debugging */
 833 };
 834
 835 static int cifs_ci_hash(const struct dentry *dentry, struct qstr *q)
 836 {
 837         struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;
 838         unsigned long hash;
 839         wchar_t c;
 840         int i, charlen;
 841
 842         hash = init_name_hash();
 843         for (i = 0; i < q->len; i += charlen) {
 844                 charlen = codepage->char2uni(&q->name[i], q->len - i, &c);
 845                 /* error out if we can't convert the character */
 846                 if (unlikely(charlen < 0))
 847                         return charlen;
 848                 hash = partial_name_hash(cifs_toupper(c), hash);
 849         }
 850         q->hash = end_name_hash(hash);
 851
 852         return 0;
 853 }
 854
 855 static int cifs_ci_compare(const struct dentry *parent, const struct dentry *dentry,
 856                 unsigned int len, const char *str, const struct qstr *name)
 857 {
 858         struct nls_table *codepage = CIFS_SB(parent->d_sb)->local_nls;
 859         wchar_t c1, c2;
 860         int i, l1, l2;
 861
 862         /*
 863          * We make the assumption here that uppercase characters in the local
 864          * codepage are always the same length as their lowercase counterparts.
 865          *
 866          * If that's ever not the case, then this will fail to match it.
 867          */
 868         if (name->len != len)
 869                 return 1;
 870
 871         for (i = 0; i < len; i += l1) {
 872                 /* Convert characters in both strings to UTF-16. */
 873                 l1 = codepage->char2uni(&str[i], len - i, &c1);
 874                 l2 = codepage->char2uni(&name->name[i], name->len - i, &c2);
 875
 876                 /*
 877                  * If we can't convert either character, just declare it to
 878                  * be 1 byte long and compare the original byte.
 879                  */
 880                 if (unlikely(l1 < 0 && l2 < 0)) {
 881                         if (str[i] != name->name[i])
 882                                 return 1;
 883                         l1 = 1;
 884                         continue;
 885                 }
 886
 887                 /*
 888                  * Here, we again ass|u|me that upper/lowercase versions of
 889                  * a character are the same length in the local NLS.
 890                  */
 891                 if (l1 != l2)
 892                         return 1;
 893
 894                 /* Now compare uppercase versions of these characters */
 895                 if (cifs_toupper(c1) != cifs_toupper(c2))
 896                         return 1;
 897         }
 898
 899         return 0;
 900 }
 901
 902 const struct dentry_operations cifs_ci_dentry_ops = {
 903         .d_revalidate = cifs_d_revalidate,
 904         .d_hash = cifs_ci_hash,
 905         .d_compare = cifs_ci_compare,
 906         .d_automount = cifs_dfs_d_automount,
 907 };