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         int pplen = 0;
  88         char *full_path;
  89         char dirsep;
  90         struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
  91         struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
  92         unsigned seq;
  93
  94         dirsep = CIFS_DIR_SEP(cifs_sb);
  95         if (tcon->Flags & SMB_SHARE_IS_IN_DFS)
  96                 dfsplen = strnlen(tcon->treeName, 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 cifs_bp_rename_retry:
 104         namelen = dfsplen + pplen;
 105         seq = read_seqbegin(&rename_lock);
 106         rcu_read_lock();
 107         for (temp = direntry; !IS_ROOT(temp);) {
 108                 namelen += (1 + temp->d_name.len);
 109                 temp = temp->d_parent;
 110                 if (temp == NULL) {
 111                         cifs_dbg(VFS, "corrupt dentry\n");
 112                         rcu_read_unlock();
 113                         return NULL;
 114                 }
 115         }
 116         rcu_read_unlock();
 117
 118         full_path = kmalloc(namelen+1, GFP_KERNEL);
 119         if (full_path == NULL)
 120                 return full_path;
 121         full_path[namelen] = 0; /* trailing null */
 122         rcu_read_lock();
 123         for (temp = direntry; !IS_ROOT(temp);) {
 124                 spin_lock(&temp->d_lock);
 125                 namelen -= 1 + temp->d_name.len;
 126                 if (namelen < 0) {
 127                         spin_unlock(&temp->d_lock);
 128                         break;
 129                 } else {
 130                         full_path[namelen] = dirsep;
 131                         strncpy(full_path + namelen + 1, temp->d_name.name,
 132                                 temp->d_name.len);
 133                         cifs_dbg(FYI, "name: %s\n", full_path + namelen);
 134                 }
 135                 spin_unlock(&temp->d_lock);
 136                 temp = temp->d_parent;
 137                 if (temp == NULL) {
 138                         cifs_dbg(VFS, "corrupt dentry\n");
 139                         rcu_read_unlock();
 140                         kfree(full_path);
 141                         return NULL;
 142                 }
 143         }
 144         rcu_read_unlock();
 145         if (namelen != dfsplen + pplen || read_seqretry(&rename_lock, seq)) {
 146                 cifs_dbg(FYI, "did not end path lookup where expected. namelen=%ddfsplen=%d\n",
 147                          namelen, dfsplen);
 148                 /* presumably this is only possible if racing with a rename
 149                 of one of the parent directories  (we can not lock the dentries
 150                 above us to prevent this, but retrying should be harmless) */
 151                 kfree(full_path);
 152                 goto cifs_bp_rename_retry;
 153         }
 154         /* DIR_SEP already set for byte  0 / vs \ but not for
 155            subsequent slashes in prepath which currently must
 156            be entered the right way - not sure if there is an alternative
 157            since the '\' is a valid posix character so we can not switch
 158            those safely to '/' if any are found in the middle of the prepath */
 159         /* BB test paths to Windows with '/' in the midst of prepath */
 160
 161         if (pplen) {
 162                 int i;
 163
 164                 cifs_dbg(FYI, "using cifs_sb prepath <%s>\n", cifs_sb->prepath);
 165                 memcpy(full_path+dfsplen+1, cifs_sb->prepath, pplen-1);
 166                 full_path[dfsplen] = dirsep;
 167                 for (i = 0; i < pplen-1; i++)
 168                         if (full_path[dfsplen+1+i] == '/')
 169                                 full_path[dfsplen+1+i] = CIFS_DIR_SEP(cifs_sb);
 170         }
 171
 172         if (dfsplen) {
 173                 strncpy(full_path, tcon->treeName, dfsplen);
 174                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS) {
 175                         int i;
 176                         for (i = 0; i < dfsplen; i++) {
 177                                 if (full_path[i] == '\\')
 178                                         full_path[i] = '/';
 179                         }
 180                 }
 181         }
 182         return full_path;
 183 }
 184
 185 /*
 186  * Don't allow path components longer than the server max.
 187  * Don't allow the separator character in a path component.
 188  * The VFS will not allow "/", but "\" is allowed by posix.
 189  */
 190 static int
 191 check_name(struct dentry *direntry, struct cifs_tcon *tcon)
 192 {
 193         struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
 194         int i;
 195
 196         if (unlikely(tcon->fsAttrInfo.MaxPathNameComponentLength &&
 197                      direntry->d_name.len >
 198                      le32_to_cpu(tcon->fsAttrInfo.MaxPathNameComponentLength)))
 199                 return -ENAMETOOLONG;
 200
 201         if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS)) {
 202                 for (i = 0; i < direntry->d_name.len; i++) {
 203                         if (direntry->d_name.name[i] == '\\') {
 204                                 cifs_dbg(FYI, "Invalid file name\n");
 205                                 return -EINVAL;
 206                         }
 207                 }
 208         }
 209         return 0;
 210 }
 211
 212
 213 /* Inode operations in similar order to how they appear in Linux file fs.h */
 214
 215 static int
 216 cifs_do_create(struct inode *inode, struct dentry *direntry, unsigned int xid,
 217                struct tcon_link *tlink, unsigned oflags, umode_t mode,
 218                __u32 *oplock, struct cifs_fid *fid)
 219 {
 220         int rc = -ENOENT;
 221         int create_options = CREATE_NOT_DIR;
 222         int desired_access;
 223         struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
 224         struct cifs_tcon *tcon = tlink_tcon(tlink);
 225         char *full_path = NULL;
 226         FILE_ALL_INFO *buf = NULL;
 227         struct inode *newinode = NULL;
 228         int disposition;
 229         struct TCP_Server_Info *server = tcon->ses->server;
 230         struct cifs_open_parms oparms;
 231
 232         *oplock = 0;
 233         if (tcon->ses->server->oplocks)
 234                 *oplock = REQ_OPLOCK;
 235
 236         full_path = build_path_from_dentry(direntry);
 237         if (full_path == NULL) {
 238                 rc = -ENOMEM;
 239                 goto out;
 240         }
 241
 242         if (tcon->unix_ext && cap_unix(tcon->ses) && !tcon->broken_posix_open &&
 243             (CIFS_UNIX_POSIX_PATH_OPS_CAP &
 244                         le64_to_cpu(tcon->fsUnixInfo.Capability))) {
 245                 rc = cifs_posix_open(full_path, &newinode, inode->i_sb, mode,
 246                                      oflags, oplock, &fid->netfid, xid);
 247                 switch (rc) {
 248                 case 0:
 249                         if (newinode == NULL) {
 250                                 /* query inode info */
 251                                 goto cifs_create_get_file_info;
 252                         }
 253
 254                         if (S_ISDIR(newinode->i_mode)) {
 255                                 CIFSSMBClose(xid, tcon, fid->netfid);
 256                                 iput(newinode);
 257                                 rc = -EISDIR;
 258                                 goto out;
 259                         }
 260
 261                         if (!S_ISREG(newinode->i_mode)) {
 262                                 /*
 263                                  * The server may allow us to open things like
 264                                  * FIFOs, but the client isn't set up to deal
 265                                  * with that. If it's not a regular file, just
 266                                  * close it and proceed as if it were a normal
 267                                  * lookup.
 268                                  */
 269                                 CIFSSMBClose(xid, tcon, fid->netfid);
 270                                 goto cifs_create_get_file_info;
 271                         }
 272                         /* success, no need to query */
 273                         goto cifs_create_set_dentry;
 274
 275                 case -ENOENT:
 276                         goto cifs_create_get_file_info;
 277
 278                 case -EIO:
 279                 case -EINVAL:
 280                         /*
 281                          * EIO could indicate that (posix open) operation is not
 282                          * supported, despite what server claimed in capability
 283                          * negotiation.
 284                          *
 285                          * POSIX open in samba versions 3.3.1 and earlier could
 286                          * incorrectly fail with invalid parameter.
 287                          */
 288                         tcon->broken_posix_open = true;
 289                         break;
 290
 291                 case -EREMOTE:
 292                 case -EOPNOTSUPP:
 293                         /*
 294                          * EREMOTE indicates DFS junction, which is not handled
 295                          * in posix open.  If either that or op not supported
 296                          * returned, follow the normal lookup.
 297                          */
 298                         break;
 299
 300                 default:
 301                         goto out;
 302                 }
 303                 /*
 304                  * fallthrough to retry, using older open call, this is case
 305                  * where server does not support this SMB level, and falsely
 306                  * claims capability (also get here for DFS case which should be
 307                  * rare for path not covered on files)
 308                  */
 309         }
 310
 311         desired_access = 0;
 312         if (OPEN_FMODE(oflags) & FMODE_READ)
 313                 desired_access |= GENERIC_READ; /* is this too little? */
 314         if (OPEN_FMODE(oflags) & FMODE_WRITE)
 315                 desired_access |= GENERIC_WRITE;
 316
 317         disposition = FILE_OVERWRITE_IF;
 318         if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
 319                 disposition = FILE_CREATE;
 320         else if ((oflags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))
 321                 disposition = FILE_OVERWRITE_IF;
 322         else if ((oflags & O_CREAT) == O_CREAT)
 323                 disposition = FILE_OPEN_IF;
 324         else
 325                 cifs_dbg(FYI, "Create flag not set in create function\n");
 326
 327         /*
 328          * BB add processing to set equivalent of mode - e.g. via CreateX with
 329          * ACLs
 330          */
 331
 332         if (!server->ops->open) {
 333                 rc = -ENOSYS;
 334                 goto out;
 335         }
 336
 337         buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
 338         if (buf == NULL) {
 339                 rc = -ENOMEM;
 340                 goto out;
 341         }
 342
 343         /*
 344          * if we're not using unix extensions, see if we need to set
 345          * ATTR_READONLY on the create call
 346          */
 347         if (!tcon->unix_ext && (mode & S_IWUGO) == 0)
 348                 create_options |= CREATE_OPTION_READONLY;
 349
 350         if (backup_cred(cifs_sb))
 351                 create_options |= CREATE_OPEN_BACKUP_INTENT;
 352
 353         oparms.tcon = tcon;
 354         oparms.cifs_sb = cifs_sb;
 355         oparms.desired_access = desired_access;
 356         oparms.create_options = create_options;
 357         oparms.disposition = disposition;
 358         oparms.path = full_path;
 359         oparms.fid = fid;
 360         oparms.reconnect = false;
 361
 362         rc = server->ops->open(xid, &oparms, oplock, buf);
 363         if (rc) {
 364                 cifs_dbg(FYI, "cifs_create returned 0x%x\n", rc);
 365                 goto out;
 366         }
 367
 368         /*
 369          * If Open reported that we actually created a file then we now have to
 370          * set the mode if possible.
 371          */
 372         if ((tcon->unix_ext) && (*oplock & CIFS_CREATE_ACTION)) {
 373                 struct cifs_unix_set_info_args args = {
 374                                 .mode   = mode,
 375                                 .ctime  = NO_CHANGE_64,
 376                                 .atime  = NO_CHANGE_64,
 377                                 .mtime  = NO_CHANGE_64,
 378                                 .device = 0,
 379                 };
 380
 381                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
 382                         args.uid = current_fsuid();
 383                         if (inode->i_mode & S_ISGID)
 384                                 args.gid = inode->i_gid;
 385                         else
 386                                 args.gid = current_fsgid();
 387                 } else {
 388                         args.uid = INVALID_UID; /* no change */
 389                         args.gid = INVALID_GID; /* no change */
 390                 }
 391                 CIFSSMBUnixSetFileInfo(xid, tcon, &args, fid->netfid,
 392                                        current->tgid);
 393         } else {
 394                 /*
 395                  * BB implement mode setting via Windows security
 396                  * descriptors e.g.
 397                  */
 398                 /* CIFSSMBWinSetPerms(xid,tcon,path,mode,-1,-1,nls);*/
 399
 400                 /* Could set r/o dos attribute if mode & 0222 == 0 */
 401         }
 402
 403 cifs_create_get_file_info:
 404         /* server might mask mode so we have to query for it */
 405         if (tcon->unix_ext)
 406                 rc = cifs_get_inode_info_unix(&newinode, full_path, inode->i_sb,
 407                                               xid);
 408         else {
 409                 rc = cifs_get_inode_info(&newinode, full_path, buf, inode->i_sb,
 410                                          xid, fid);
 411                 if (newinode) {
 412                         if (server->ops->set_lease_key)
 413                                 server->ops->set_lease_key(newinode, fid);
 414                         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DYNPERM)
 415                                 newinode->i_mode = mode;
 416                         if ((*oplock & CIFS_CREATE_ACTION) &&
 417                             (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID)) {
 418                                 newinode->i_uid = current_fsuid();
 419                                 if (inode->i_mode & S_ISGID)
 420                                         newinode->i_gid = inode->i_gid;
 421                                 else
 422                                         newinode->i_gid = current_fsgid();
 423                         }
 424                 }
 425         }
 426
 427 cifs_create_set_dentry:
 428         if (rc != 0) {
 429                 cifs_dbg(FYI, "Create worked, get_inode_info failed rc = %d\n",
 430                          rc);
 431                 goto out_err;
 432         }
 433
 434         if (S_ISDIR(newinode->i_mode)) {
 435                 rc = -EISDIR;
 436                 goto out_err;
 437         }
 438
 439         d_drop(direntry);
 440         d_add(direntry, newinode);
 441
 442 out:
 443         kfree(buf);
 444         kfree(full_path);
 445         return rc;
 446
 447 out_err:
 448         if (server->ops->close)
 449                 server->ops->close(xid, tcon, fid);
 450         if (newinode)
 451                 iput(newinode);
 452         goto out;
 453 }
 454
 455 int
 456 cifs_atomic_open(struct inode *inode, struct dentry *direntry,
 457                  struct file *file, unsigned oflags, umode_t mode,
 458                  int *opened)
 459 {
 460         int rc;
 461         unsigned int xid;
 462         struct tcon_link *tlink;
 463         struct cifs_tcon *tcon;
 464         struct TCP_Server_Info *server;
 465         struct cifs_fid fid;
 466         struct cifs_pending_open open;
 467         __u32 oplock;
 468         struct cifsFileInfo *file_info;
 469
 470         /*
 471          * Posix open is only called (at lookup time) for file create now. For
 472          * opens (rather than creates), because we do not know if it is a file
 473          * or directory yet, and current Samba no longer allows us to do posix
 474          * open on dirs, we could end up wasting an open call on what turns out
 475          * to be a dir. For file opens, we wait to call posix open till
 476          * cifs_open.  It could be added to atomic_open in the future but the
 477          * performance tradeoff of the extra network request when EISDIR or
 478          * EACCES is returned would have to be weighed against the 50% reduction
 479          * in network traffic in the other paths.
 480          */
 481         if (!(oflags & O_CREAT)) {
 482                 struct dentry *res;
 483
 484                 /*
 485                  * Check for hashed negative dentry. We have already revalidated
 486                  * the dentry and it is fine. No need to perform another lookup.
 487                  */
 488                 if (!d_unhashed(direntry))
 489                         return -ENOENT;
 490
 491                 res = cifs_lookup(inode, direntry, 0);
 492                 if (IS_ERR(res))
 493                         return PTR_ERR(res);
 494
 495                 return finish_no_open(file, res);
 496         }
 497
 498         xid = get_xid();
 499
 500         cifs_dbg(FYI, "parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
 501                  inode, direntry, direntry);
 502
 503         tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));
 504         if (IS_ERR(tlink)) {
 505                 rc = PTR_ERR(tlink);
 506                 goto out_free_xid;
 507         }
 508
 509         tcon = tlink_tcon(tlink);
 510
 511         rc = check_name(direntry, tcon);
 512         if (rc)
 513                 goto out;
 514
 515         server = tcon->ses->server;
 516
 517         if (server->ops->new_lease_key)
 518                 server->ops->new_lease_key(&fid);
 519
 520         cifs_add_pending_open(&fid, tlink, &open);
 521
 522         rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode,
 523                             &oplock, &fid);
 524
 525         if (rc) {
 526                 cifs_del_pending_open(&open);
 527                 goto out;
 528         }
 529
 530         if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
 531                 *opened |= FILE_CREATED;
 532
 533         rc = finish_open(file, direntry, generic_file_open, opened);
 534         if (rc) {
 535                 if (server->ops->close)
 536                         server->ops->close(xid, tcon, &fid);
 537                 cifs_del_pending_open(&open);
 538                 goto out;
 539         }
 540
 541         if (file->f_flags & O_DIRECT &&
 542             CIFS_SB(inode->i_sb)->mnt_cifs_flags & CIFS_MOUNT_STRICT_IO) {
 543                 if (CIFS_SB(inode->i_sb)->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
 544                         file->f_op = &cifs_file_direct_nobrl_ops;
 545                 else
 546                         file->f_op = &cifs_file_direct_ops;
 547                 }
 548
 549         file_info = cifs_new_fileinfo(&fid, file, tlink, oplock);
 550         if (file_info == NULL) {
 551                 if (server->ops->close)
 552                         server->ops->close(xid, tcon, &fid);
 553                 cifs_del_pending_open(&open);
 554                 fput(file);
 555                 rc = -ENOMEM;
 556         }
 557
 558 out:
 559         cifs_put_tlink(tlink);
 560 out_free_xid:
 561         free_xid(xid);
 562         return rc;
 563 }
 564
 565 int cifs_create(struct inode *inode, struct dentry *direntry, umode_t mode,
 566                 bool excl)
 567 {
 568         int rc;
 569         unsigned int xid = get_xid();
 570         /*
 571          * BB below access is probably too much for mknod to request
 572          *    but we have to do query and setpathinfo so requesting
 573          *    less could fail (unless we want to request getatr and setatr
 574          *    permissions (only).  At least for POSIX we do not have to
 575          *    request so much.
 576          */
 577         unsigned oflags = O_EXCL | O_CREAT | O_RDWR;
 578         struct tcon_link *tlink;
 579         struct cifs_tcon *tcon;
 580         struct TCP_Server_Info *server;
 581         struct cifs_fid fid;
 582         __u32 oplock;
 583
 584         cifs_dbg(FYI, "cifs_create parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
 585                  inode, direntry, direntry);
 586
 587         tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));
 588         rc = PTR_ERR(tlink);
 589         if (IS_ERR(tlink))
 590                 goto out_free_xid;
 591
 592         tcon = tlink_tcon(tlink);
 593         server = tcon->ses->server;
 594
 595         if (server->ops->new_lease_key)
 596                 server->ops->new_lease_key(&fid);
 597
 598         rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode,
 599                             &oplock, &fid);
 600         if (!rc && server->ops->close)
 601                 server->ops->close(xid, tcon, &fid);
 602
 603         cifs_put_tlink(tlink);
 604 out_free_xid:
 605         free_xid(xid);
 606         return rc;
 607 }
 608
 609 int cifs_mknod(struct inode *inode, struct dentry *direntry, umode_t mode,
 610                 dev_t device_number)
 611 {
 612         int rc = -EPERM;
 613         unsigned int xid;
 614         int create_options = CREATE_NOT_DIR | CREATE_OPTION_SPECIAL;
 615         struct cifs_sb_info *cifs_sb;
 616         struct tcon_link *tlink;
 617         struct cifs_tcon *tcon;
 618         struct cifs_io_parms io_parms;
 619         char *full_path = NULL;
 620         struct inode *newinode = NULL;
 621         __u32 oplock = 0;
 622         struct cifs_fid fid;
 623         struct cifs_open_parms oparms;
 624         FILE_ALL_INFO *buf = NULL;
 625         unsigned int bytes_written;
 626         struct win_dev *pdev;
 627         struct kvec iov[2];
 628
 629         if (!old_valid_dev(device_number))
 630                 return -EINVAL;
 631
 632         cifs_sb = CIFS_SB(inode->i_sb);
 633         tlink = cifs_sb_tlink(cifs_sb);
 634         if (IS_ERR(tlink))
 635                 return PTR_ERR(tlink);
 636
 637         tcon = tlink_tcon(tlink);
 638
 639         xid = get_xid();
 640
 641         full_path = build_path_from_dentry(direntry);
 642         if (full_path == NULL) {
 643                 rc = -ENOMEM;
 644                 goto mknod_out;
 645         }
 646
 647         if (tcon->unix_ext) {
 648                 struct cifs_unix_set_info_args args = {
 649                         .mode   = mode & ~current_umask(),
 650                         .ctime  = NO_CHANGE_64,
 651                         .atime  = NO_CHANGE_64,
 652                         .mtime  = NO_CHANGE_64,
 653                         .device = device_number,
 654                 };
 655                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
 656                         args.uid = current_fsuid();
 657                         args.gid = current_fsgid();
 658                 } else {
 659                         args.uid = INVALID_UID; /* no change */
 660                         args.gid = INVALID_GID; /* no change */
 661                 }
 662                 rc = CIFSSMBUnixSetPathInfo(xid, tcon, full_path, &args,
 663                                             cifs_sb->local_nls,
 664                                             cifs_remap(cifs_sb));
 665                 if (rc)
 666                         goto mknod_out;
 667
 668                 rc = cifs_get_inode_info_unix(&newinode, full_path,
 669                                                 inode->i_sb, xid);
 670
 671                 if (rc == 0)
 672                         d_instantiate(direntry, newinode);
 673                 goto mknod_out;
 674         }
 675
 676         if (!S_ISCHR(mode) && !S_ISBLK(mode))
 677                 goto mknod_out;
 678
 679         if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL))
 680                 goto mknod_out;
 681
 682
 683         cifs_dbg(FYI, "sfu compat create special file\n");
 684
 685         buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
 686         if (buf == NULL) {
 687                 rc = -ENOMEM;
 688                 goto mknod_out;
 689         }
 690
 691         if (backup_cred(cifs_sb))
 692                 create_options |= CREATE_OPEN_BACKUP_INTENT;
 693
 694         oparms.tcon = tcon;
 695         oparms.cifs_sb = cifs_sb;
 696         oparms.desired_access = GENERIC_WRITE;
 697         oparms.create_options = create_options;
 698         oparms.disposition = FILE_CREATE;
 699         oparms.path = full_path;
 700         oparms.fid = &fid;
 701         oparms.reconnect = false;
 702
 703         if (tcon->ses->server->oplocks)
 704                 oplock = REQ_OPLOCK;
 705         else
 706                 oplock = 0;
 707         rc = tcon->ses->server->ops->open(xid, &oparms, &oplock, buf);
 708         if (rc)
 709                 goto mknod_out;
 710
 711         /*
 712          * BB Do not bother to decode buf since no local inode yet to put
 713          * timestamps in, but we can reuse it safely.
 714          */
 715
 716         pdev = (struct win_dev *)buf;
 717         io_parms.pid = current->tgid;
 718         io_parms.tcon = tcon;
 719         io_parms.offset = 0;
 720         io_parms.length = sizeof(struct win_dev);
 721         iov[1].iov_base = buf;
 722         iov[1].iov_len = sizeof(struct win_dev);
 723         if (S_ISCHR(mode)) {
 724                 memcpy(pdev->type, "IntxCHR", 8);
 725                 pdev->major = cpu_to_le64(MAJOR(device_number));
 726                 pdev->minor = cpu_to_le64(MINOR(device_number));
 727                 rc = tcon->ses->server->ops->sync_write(xid, &fid, &io_parms,
 728                                                         &bytes_written, iov, 1);
 729         } else if (S_ISBLK(mode)) {
 730                 memcpy(pdev->type, "IntxBLK", 8);
 731                 pdev->major = cpu_to_le64(MAJOR(device_number));
 732                 pdev->minor = cpu_to_le64(MINOR(device_number));
 733                 rc = tcon->ses->server->ops->sync_write(xid, &fid, &io_parms,
 734                                                         &bytes_written, iov, 1);
 735         }
 736         tcon->ses->server->ops->close(xid, tcon, &fid);
 737         d_drop(direntry);
 738
 739         /* FIXME: add code here to set EAs */
 740
 741 mknod_out:
 742         kfree(full_path);
 743         kfree(buf);
 744         free_xid(xid);
 745         cifs_put_tlink(tlink);
 746         return rc;
 747 }
 748
 749 struct dentry *
 750 cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,
 751             unsigned int flags)
 752 {
 753         unsigned int xid;
 754         int rc = 0; /* to get around spurious gcc warning, set to zero here */
 755         struct cifs_sb_info *cifs_sb;
 756         struct tcon_link *tlink;
 757         struct cifs_tcon *pTcon;
 758         struct inode *newInode = NULL;
 759         char *full_path = NULL;
 760
 761         xid = get_xid();
 762
 763         cifs_dbg(FYI, "parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
 764                  parent_dir_inode, direntry, direntry);
 765
 766         /* check whether path exists */
 767
 768         cifs_sb = CIFS_SB(parent_dir_inode->i_sb);
 769         tlink = cifs_sb_tlink(cifs_sb);
 770         if (IS_ERR(tlink)) {
 771                 free_xid(xid);
 772                 return (struct dentry *)tlink;
 773         }
 774         pTcon = tlink_tcon(tlink);
 775
 776         rc = check_name(direntry, pTcon);
 777         if (rc)
 778                 goto lookup_out;
 779
 780         /* can not grab the rename sem here since it would
 781         deadlock in the cases (beginning of sys_rename itself)
 782         in which we already have the sb rename sem */
 783         full_path = build_path_from_dentry(direntry);
 784         if (full_path == NULL) {
 785                 rc = -ENOMEM;
 786                 goto lookup_out;
 787         }
 788
 789         if (d_really_is_positive(direntry)) {
 790                 cifs_dbg(FYI, "non-NULL inode in lookup\n");
 791         } else {
 792                 cifs_dbg(FYI, "NULL inode in lookup\n");
 793         }
 794         cifs_dbg(FYI, "Full path: %s inode = 0x%p\n",
 795                  full_path, d_inode(direntry));
 796
 797         if (pTcon->unix_ext) {
 798                 rc = cifs_get_inode_info_unix(&newInode, full_path,
 799                                               parent_dir_inode->i_sb, xid);
 800         } else {
 801                 rc = cifs_get_inode_info(&newInode, full_path, NULL,
 802                                 parent_dir_inode->i_sb, xid, NULL);
 803         }
 804
 805         if ((rc == 0) && (newInode != NULL)) {
 806                 d_add(direntry, newInode);
 807                 /* since paths are not looked up by component - the parent
 808                    directories are presumed to be good here */
 809                 renew_parental_timestamps(direntry);
 810
 811         } else if (rc == -ENOENT) {
 812                 rc = 0;
 813                 direntry->d_time = jiffies;
 814                 d_add(direntry, NULL);
 815         /*      if it was once a directory (but how can we tell?) we could do
 816                 shrink_dcache_parent(direntry); */
 817         } else if (rc != -EACCES) {
 818                 cifs_dbg(FYI, "Unexpected lookup error %d\n", rc);
 819                 /* We special case check for Access Denied - since that
 820                 is a common return code */
 821         }
 822
 823 lookup_out:
 824         kfree(full_path);
 825         cifs_put_tlink(tlink);
 826         free_xid(xid);
 827         return ERR_PTR(rc);
 828 }
 829
 830 static int
 831 cifs_d_revalidate(struct dentry *direntry, unsigned int flags)
 832 {
 833         struct inode *inode;
 834         int rc;
 835
 836         if (flags & LOOKUP_RCU)
 837                 return -ECHILD;
 838
 839         if (d_really_is_positive(direntry)) {
 840                 inode = d_inode(direntry);
 841                 if ((flags & LOOKUP_REVAL) && !CIFS_CACHE_READ(CIFS_I(inode)))
 842                         CIFS_I(inode)->time = 0; /* force reval */
 843
 844                 rc = cifs_revalidate_dentry(direntry);
 845                 if (rc) {
 846                         cifs_dbg(FYI, "cifs_revalidate_dentry failed with rc=%d", rc);
 847                         switch (rc) {
 848                         case -ENOENT:
 849                         case -ESTALE:
 850                                 /*
 851                                  * Those errors mean the dentry is invalid
 852                                  * (file was deleted or recreated)
 853                                  */
 854                                 return 0;
 855                         default:
 856                                 /*
 857                                  * Otherwise some unexpected error happened
 858                                  * report it as-is to VFS layer
 859                                  */
 860                                 return rc;
 861                         }
 862                 }
 863                 else {
 864                         /*
 865                          * If the inode wasn't known to be a dfs entry when
 866                          * the dentry was instantiated, such as when created
 867                          * via ->readdir(), it needs to be set now since the
 868                          * attributes will have been updated by
 869                          * cifs_revalidate_dentry().
 870                          */
 871                         if (IS_AUTOMOUNT(inode) &&
 872                            !(direntry->d_flags & DCACHE_NEED_AUTOMOUNT)) {
 873                                 spin_lock(&direntry->d_lock);
 874                                 direntry->d_flags |= DCACHE_NEED_AUTOMOUNT;
 875                                 spin_unlock(&direntry->d_lock);
 876                         }
 877
 878                         return 1;
 879                 }
 880         }
 881
 882         /*
 883          * This may be nfsd (or something), anyway, we can't see the
 884          * intent of this. So, since this can be for creation, drop it.
 885          */
 886         if (!flags)
 887                 return 0;
 888
 889         /*
 890          * Drop the negative dentry, in order to make sure to use the
 891          * case sensitive name which is specified by user if this is
 892          * for creation.
 893          */
 894         if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))
 895                 return 0;
 896
 897         if (time_after(jiffies, direntry->d_time + HZ) || !lookupCacheEnabled)
 898                 return 0;
 899
 900         return 1;
 901 }
 902
 903 /* static int cifs_d_delete(struct dentry *direntry)
 904 {
 905         int rc = 0;
 906
 907         cifs_dbg(FYI, "In cifs d_delete, name = %pd\n", direntry);
 908
 909         return rc;
 910 }     */
 911
 912 const struct dentry_operations cifs_dentry_ops = {
 913         .d_revalidate = cifs_d_revalidate,
 914         .d_automount = cifs_dfs_d_automount,
 915 /* d_delete:       cifs_d_delete,      */ /* not needed except for debugging */
 916 };
 917
 918 static int cifs_ci_hash(const struct dentry *dentry, struct qstr *q)
 919 {
 920         struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;
 921         unsigned long hash;
 922         wchar_t c;
 923         int i, charlen;
 924
 925         hash = init_name_hash();
 926         for (i = 0; i < q->len; i += charlen) {
 927                 charlen = codepage->char2uni(&q->name[i], q->len - i, &c);
 928                 /* error out if we can't convert the character */
 929                 if (unlikely(charlen < 0))
 930                         return charlen;
 931                 hash = partial_name_hash(cifs_toupper(c), hash);
 932         }
 933         q->hash = end_name_hash(hash);
 934
 935         return 0;
 936 }
 937
 938 static int cifs_ci_compare(const struct dentry *parent, const struct dentry *dentry,
 939                 unsigned int len, const char *str, const struct qstr *name)
 940 {
 941         struct nls_table *codepage = CIFS_SB(parent->d_sb)->local_nls;
 942         wchar_t c1, c2;
 943         int i, l1, l2;
 944
 945         /*
 946          * We make the assumption here that uppercase characters in the local
 947          * codepage are always the same length as their lowercase counterparts.
 948          *
 949          * If that's ever not the case, then this will fail to match it.
 950          */
 951         if (name->len != len)
 952                 return 1;
 953
 954         for (i = 0; i < len; i += l1) {
 955                 /* Convert characters in both strings to UTF-16. */
 956                 l1 = codepage->char2uni(&str[i], len - i, &c1);
 957                 l2 = codepage->char2uni(&name->name[i], name->len - i, &c2);
 958
 959                 /*
 960                  * If we can't convert either character, just declare it to
 961                  * be 1 byte long and compare the original byte.
 962                  */
 963                 if (unlikely(l1 < 0 && l2 < 0)) {
 964                         if (str[i] != name->name[i])
 965                                 return 1;
 966                         l1 = 1;
 967                         continue;
 968                 }
 969
 970                 /*
 971                  * Here, we again ass|u|me that upper/lowercase versions of
 972                  * a character are the same length in the local NLS.
 973                  */
 974                 if (l1 != l2)
 975                         return 1;
 976
 977                 /* Now compare uppercase versions of these characters */
 978                 if (cifs_toupper(c1) != cifs_toupper(c2))
 979                         return 1;
 980         }
 981
 982         return 0;
 983 }
 984
 985 const struct dentry_operations cifs_ci_dentry_ops = {
 986         .d_revalidate = cifs_d_revalidate,
 987         .d_hash = cifs_ci_hash,
 988         .d_compare = cifs_ci_compare,
 989         .d_automount = cifs_dfs_d_automount,
 990 };