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                 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 cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
  85         struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
  86         bool prefix = tcon->Flags & SMB_SHARE_IS_IN_DFS;
  87
  88         return build_path_from_dentry_optional_prefix(direntry,
  89                                                       prefix);
  90 }
  91
  92 char *
  93 build_path_from_dentry_optional_prefix(struct dentry *direntry, bool prefix)
  94 {
  95         struct dentry *temp;
  96         int namelen;
  97         int dfsplen;
  98         int pplen = 0;
  99         char *full_path;
 100         char dirsep;
 101         struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
 102         struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
 103         unsigned seq;
 104
 105         dirsep = CIFS_DIR_SEP(cifs_sb);
 106         if (prefix)
 107                 dfsplen = strnlen(tcon->treeName, MAX_TREE_SIZE + 1);
 108         else
 109                 dfsplen = 0;
 110
 111         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH)
 112                 pplen = cifs_sb->prepath ? strlen(cifs_sb->prepath) + 1 : 0;
 113
 114 cifs_bp_rename_retry:
 115         namelen = dfsplen + pplen;
 116         seq = read_seqbegin(&rename_lock);
 117         rcu_read_lock();
 118         for (temp = direntry; !IS_ROOT(temp);) {
 119                 namelen += (1 + temp->d_name.len);
 120                 temp = temp->d_parent;
 121                 if (temp == NULL) {
 122                         cifs_dbg(VFS, "corrupt dentry\n");
 123                         rcu_read_unlock();
 124                         return NULL;
 125                 }
 126         }
 127         rcu_read_unlock();
 128
 129         full_path = kmalloc(namelen+1, GFP_KERNEL);
 130         if (full_path == NULL)
 131                 return full_path;
 132         full_path[namelen] = 0; /* trailing null */
 133         rcu_read_lock();
 134         for (temp = direntry; !IS_ROOT(temp);) {
 135                 spin_lock(&temp->d_lock);
 136                 namelen -= 1 + temp->d_name.len;
 137                 if (namelen < 0) {
 138                         spin_unlock(&temp->d_lock);
 139                         break;
 140                 } else {
 141                         full_path[namelen] = dirsep;
 142                         strncpy(full_path + namelen + 1, temp->d_name.name,
 143                                 temp->d_name.len);
 144                         cifs_dbg(FYI, "name: %s\n", full_path + namelen);
 145                 }
 146                 spin_unlock(&temp->d_lock);
 147                 temp = temp->d_parent;
 148                 if (temp == NULL) {
 149                         cifs_dbg(VFS, "corrupt dentry\n");
 150                         rcu_read_unlock();
 151                         kfree(full_path);
 152                         return NULL;
 153                 }
 154         }
 155         rcu_read_unlock();
 156         if (namelen != dfsplen + pplen || read_seqretry(&rename_lock, seq)) {
 157                 cifs_dbg(FYI, "did not end path lookup where expected. namelen=%ddfsplen=%d\n",
 158                          namelen, dfsplen);
 159                 /* presumably this is only possible if racing with a rename
 160                 of one of the parent directories  (we can not lock the dentries
 161                 above us to prevent this, but retrying should be harmless) */
 162                 kfree(full_path);
 163                 goto cifs_bp_rename_retry;
 164         }
 165         /* DIR_SEP already set for byte  0 / vs \ but not for
 166            subsequent slashes in prepath which currently must
 167            be entered the right way - not sure if there is an alternative
 168            since the '\' is a valid posix character so we can not switch
 169            those safely to '/' if any are found in the middle of the prepath */
 170         /* BB test paths to Windows with '/' in the midst of prepath */
 171
 172         if (pplen) {
 173                 int i;
 174
 175                 cifs_dbg(FYI, "using cifs_sb prepath <%s>\n", cifs_sb->prepath);
 176                 memcpy(full_path+dfsplen+1, cifs_sb->prepath, pplen-1);
 177                 full_path[dfsplen] = '\\';
 178                 for (i = 0; i < pplen-1; i++)
 179                         if (full_path[dfsplen+1+i] == '/')
 180                                 full_path[dfsplen+1+i] = CIFS_DIR_SEP(cifs_sb);
 181         }
 182
 183         if (dfsplen) {
 184                 strncpy(full_path, tcon->treeName, dfsplen);
 185                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS) {
 186                         int i;
 187                         for (i = 0; i < dfsplen; i++) {
 188                                 if (full_path[i] == '\\')
 189                                         full_path[i] = '/';
 190                         }
 191                 }
 192         }
 193         return full_path;
 194 }
 195
 196 /*
 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)
 202 {
 203         struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
 204         int i;
 205
 206         if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS)) {
 207                 for (i = 0; i < direntry->d_name.len; i++) {
 208                         if (direntry->d_name.name[i] == '\\') {
 209                                 cifs_dbg(FYI, "Invalid file name\n");
 210                                 return -EINVAL;
 211                         }
 212                 }
 213         }
 214         return 0;
 215 }
 216
 217
 218 /* Inode operations in similar order to how they appear in Linux file fs.h */
 219
 220 static int
 221 cifs_do_create(struct inode *inode, struct dentry *direntry, unsigned int xid,
 222                struct tcon_link *tlink, unsigned oflags, umode_t mode,
 223                __u32 *oplock, struct cifs_fid *fid)
 224 {
 225         int rc = -ENOENT;
 226         int create_options = CREATE_NOT_DIR;
 227         int desired_access;
 228         struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
 229         struct cifs_tcon *tcon = tlink_tcon(tlink);
 230         char *full_path = NULL;
 231         FILE_ALL_INFO *buf = NULL;
 232         struct inode *newinode = NULL;
 233         int disposition;
 234         struct TCP_Server_Info *server = tcon->ses->server;
 235         struct cifs_open_parms oparms;
 236
 237         *oplock = 0;
 238         if (tcon->ses->server->oplocks)
 239                 *oplock = REQ_OPLOCK;
 240
 241         full_path = build_path_from_dentry(direntry);
 242         if (full_path == NULL) {
 243                 rc = -ENOMEM;
 244                 goto out;
 245         }
 246
 247         if (tcon->unix_ext && cap_unix(tcon->ses) && !tcon->broken_posix_open &&
 248             (CIFS_UNIX_POSIX_PATH_OPS_CAP &
 249                         le64_to_cpu(tcon->fsUnixInfo.Capability))) {
 250                 rc = cifs_posix_open(full_path, &newinode, inode->i_sb, mode,
 251                                      oflags, oplock, &fid->netfid, xid);
 252                 switch (rc) {
 253                 case 0:
 254                         if (newinode == NULL) {
 255                                 /* query inode info */
 256                                 goto cifs_create_get_file_info;
 257                         }
 258
 259                         if (S_ISDIR(newinode->i_mode)) {
 260                                 CIFSSMBClose(xid, tcon, fid->netfid);
 261                                 iput(newinode);
 262                                 rc = -EISDIR;
 263                                 goto out;
 264                         }
 265
 266                         if (!S_ISREG(newinode->i_mode)) {
 267                                 /*
 268                                  * The server may allow us to open things like
 269                                  * FIFOs, but the client isn't set up to deal
 270                                  * with that. If it's not a regular file, just
 271                                  * close it and proceed as if it were a normal
 272                                  * lookup.
 273                                  */
 274                                 CIFSSMBClose(xid, tcon, fid->netfid);
 275                                 goto cifs_create_get_file_info;
 276                         }
 277                         /* success, no need to query */
 278                         goto cifs_create_set_dentry;
 279
 280                 case -ENOENT:
 281                         goto cifs_create_get_file_info;
 282
 283                 case -EIO:
 284                 case -EINVAL:
 285                         /*
 286                          * EIO could indicate that (posix open) operation is not
 287                          * supported, despite what server claimed in capability
 288                          * negotiation.
 289                          *
 290                          * POSIX open in samba versions 3.3.1 and earlier could
 291                          * incorrectly fail with invalid parameter.
 292                          */
 293                         tcon->broken_posix_open = true;
 294                         break;
 295
 296                 case -EREMOTE:
 297                 case -EOPNOTSUPP:
 298                         /*
 299                          * EREMOTE indicates DFS junction, which is not handled
 300                          * in posix open.  If either that or op not supported
 301                          * returned, follow the normal lookup.
 302                          */
 303                         break;
 304
 305                 default:
 306                         goto out;
 307                 }
 308                 /*
 309                  * fallthrough to retry, using older open call, this is case
 310                  * where server does not support this SMB level, and falsely
 311                  * claims capability (also get here for DFS case which should be
 312                  * rare for path not covered on files)
 313                  */
 314         }
 315
 316         desired_access = 0;
 317         if (OPEN_FMODE(oflags) & FMODE_READ)
 318                 desired_access |= GENERIC_READ; /* is this too little? */
 319         if (OPEN_FMODE(oflags) & FMODE_WRITE)
 320                 desired_access |= GENERIC_WRITE;
 321
 322         disposition = FILE_OVERWRITE_IF;
 323         if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
 324                 disposition = FILE_CREATE;
 325         else if ((oflags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))
 326                 disposition = FILE_OVERWRITE_IF;
 327         else if ((oflags & O_CREAT) == O_CREAT)
 328                 disposition = FILE_OPEN_IF;
 329         else
 330                 cifs_dbg(FYI, "Create flag not set in create function\n");
 331
 332         /*
 333          * BB add processing to set equivalent of mode - e.g. via CreateX with
 334          * ACLs
 335          */
 336
 337         if (!server->ops->open) {
 338                 rc = -ENOSYS;
 339                 goto out;
 340         }
 341
 342         buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
 343         if (buf == NULL) {
 344                 rc = -ENOMEM;
 345                 goto out;
 346         }
 347
 348         /*
 349          * if we're not using unix extensions, see if we need to set
 350          * ATTR_READONLY on the create call
 351          */
 352         if (!tcon->unix_ext && (mode & S_IWUGO) == 0)
 353                 create_options |= CREATE_OPTION_READONLY;
 354
 355         if (backup_cred(cifs_sb))
 356                 create_options |= CREATE_OPEN_BACKUP_INTENT;
 357
 358         oparms.tcon = tcon;
 359         oparms.cifs_sb = cifs_sb;
 360         oparms.desired_access = desired_access;
 361         oparms.create_options = create_options;
 362         oparms.disposition = disposition;
 363         oparms.path = full_path;
 364         oparms.fid = fid;
 365         oparms.reconnect = false;
 366
 367         rc = server->ops->open(xid, &oparms, oplock, buf);
 368         if (rc) {
 369                 cifs_dbg(FYI, "cifs_create returned 0x%x\n", rc);
 370                 goto out;
 371         }
 372
 373         /*
 374          * If Open reported that we actually created a file then we now have to
 375          * set the mode if possible.
 376          */
 377         if ((tcon->unix_ext) && (*oplock & CIFS_CREATE_ACTION)) {
 378                 struct cifs_unix_set_info_args args = {
 379                                 .mode   = mode,
 380                                 .ctime  = NO_CHANGE_64,
 381                                 .atime  = NO_CHANGE_64,
 382                                 .mtime  = NO_CHANGE_64,
 383                                 .device = 0,
 384                 };
 385
 386                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
 387                         args.uid = current_fsuid();
 388                         if (inode->i_mode & S_ISGID)
 389                                 args.gid = inode->i_gid;
 390                         else
 391                                 args.gid = current_fsgid();
 392                 } else {
 393                         args.uid = INVALID_UID; /* no change */
 394                         args.gid = INVALID_GID; /* no change */
 395                 }
 396                 CIFSSMBUnixSetFileInfo(xid, tcon, &args, fid->netfid,
 397                                        current->tgid);
 398         } else {
 399                 /*
 400                  * BB implement mode setting via Windows security
 401                  * descriptors e.g.
 402                  */
 403                 /* CIFSSMBWinSetPerms(xid,tcon,path,mode,-1,-1,nls);*/
 404
 405                 /* Could set r/o dos attribute if mode & 0222 == 0 */
 406         }
 407
 408 cifs_create_get_file_info:
 409         /* server might mask mode so we have to query for it */
 410         if (tcon->unix_ext)
 411                 rc = cifs_get_inode_info_unix(&newinode, full_path, inode->i_sb,
 412                                               xid);
 413         else {
 414                 rc = cifs_get_inode_info(&newinode, full_path, buf, inode->i_sb,
 415                                          xid, fid);
 416                 if (newinode) {
 417                         if (server->ops->set_lease_key)
 418                                 server->ops->set_lease_key(newinode, fid);
 419                         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DYNPERM)
 420                                 newinode->i_mode = mode;
 421                         if ((*oplock & CIFS_CREATE_ACTION) &&
 422                             (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID)) {
 423                                 newinode->i_uid = current_fsuid();
 424                                 if (inode->i_mode & S_ISGID)
 425                                         newinode->i_gid = inode->i_gid;
 426                                 else
 427                                         newinode->i_gid = current_fsgid();
 428                         }
 429                 }
 430         }
 431
 432 cifs_create_set_dentry:
 433         if (rc != 0) {
 434                 cifs_dbg(FYI, "Create worked, get_inode_info failed rc = %d\n",
 435                          rc);
 436                 goto out_err;
 437         }
 438
 439         if (S_ISDIR(newinode->i_mode)) {
 440                 rc = -EISDIR;
 441                 goto out_err;
 442         }
 443
 444         d_drop(direntry);
 445         d_add(direntry, newinode);
 446
 447 out:
 448         kfree(buf);
 449         kfree(full_path);
 450         return rc;
 451
 452 out_err:
 453         if (server->ops->close)
 454                 server->ops->close(xid, tcon, fid);
 455         if (newinode)
 456                 iput(newinode);
 457         goto out;
 458 }
 459
 460 int
 461 cifs_atomic_open(struct inode *inode, struct dentry *direntry,
 462                  struct file *file, unsigned oflags, umode_t mode,
 463                  int *opened)
 464 {
 465         int rc;
 466         unsigned int xid;
 467         struct tcon_link *tlink;
 468         struct cifs_tcon *tcon;
 469         struct TCP_Server_Info *server;
 470         struct cifs_fid fid;
 471         struct cifs_pending_open open;
 472         __u32 oplock;
 473         struct cifsFileInfo *file_info;
 474
 475         /*
 476          * Posix open is only called (at lookup time) for file create now. For
 477          * opens (rather than creates), because we do not know if it is a file
 478          * or directory yet, and current Samba no longer allows us to do posix
 479          * open on dirs, we could end up wasting an open call on what turns out
 480          * to be a dir. For file opens, we wait to call posix open till
 481          * cifs_open.  It could be added to atomic_open in the future but the
 482          * performance tradeoff of the extra network request when EISDIR or
 483          * EACCES is returned would have to be weighed against the 50% reduction
 484          * in network traffic in the other paths.
 485          */
 486         if (!(oflags & O_CREAT)) {
 487                 struct dentry *res;
 488
 489                 /*
 490                  * Check for hashed negative dentry. We have already revalidated
 491                  * the dentry and it is fine. No need to perform another lookup.
 492                  */
 493                 if (!d_in_lookup(direntry))
 494                         return -ENOENT;
 495
 496                 res = cifs_lookup(inode, direntry, 0);
 497                 if (IS_ERR(res))
 498                         return PTR_ERR(res);
 499
 500                 return finish_no_open(file, res);
 501         }
 502
 503         rc = check_name(direntry);
 504         if (rc)
 505                 return rc;
 506
 507         xid = get_xid();
 508
 509         cifs_dbg(FYI, "parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
 510                  inode, direntry, direntry);
 511
 512         tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));
 513         if (IS_ERR(tlink)) {
 514                 rc = PTR_ERR(tlink);
 515                 goto out_free_xid;
 516         }
 517
 518         tcon = tlink_tcon(tlink);
 519         server = tcon->ses->server;
 520
 521         if (server->ops->new_lease_key)
 522                 server->ops->new_lease_key(&fid);
 523
 524         cifs_add_pending_open(&fid, tlink, &open);
 525
 526         rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode,
 527                             &oplock, &fid);
 528
 529         if (rc) {
 530                 cifs_del_pending_open(&open);
 531                 goto out;
 532         }
 533
 534         if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
 535                 *opened |= FILE_CREATED;
 536
 537         rc = finish_open(file, direntry, generic_file_open, opened);
 538         if (rc) {
 539                 if (server->ops->close)
 540                         server->ops->close(xid, tcon, &fid);
 541                 cifs_del_pending_open(&open);
 542                 goto out;
 543         }
 544
 545         if (file->f_flags & O_DIRECT &&
 546             CIFS_SB(inode->i_sb)->mnt_cifs_flags & CIFS_MOUNT_STRICT_IO) {
 547                 if (CIFS_SB(inode->i_sb)->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
 548                         file->f_op = &cifs_file_direct_nobrl_ops;
 549                 else
 550                         file->f_op = &cifs_file_direct_ops;
 551                 }
 552
 553         file_info = cifs_new_fileinfo(&fid, file, tlink, oplock);
 554         if (file_info == NULL) {
 555                 if (server->ops->close)
 556                         server->ops->close(xid, tcon, &fid);
 557                 cifs_del_pending_open(&open);
 558                 fput(file);
 559                 rc = -ENOMEM;
 560         }
 561
 562 out:
 563         cifs_put_tlink(tlink);
 564 out_free_xid:
 565         free_xid(xid);
 566         return rc;
 567 }
 568
 569 int cifs_create(struct inode *inode, struct dentry *direntry, umode_t mode,
 570                 bool excl)
 571 {
 572         int rc;
 573         unsigned int xid = get_xid();
 574         /*
 575          * BB below access is probably too much for mknod to request
 576          *    but we have to do query and setpathinfo so requesting
 577          *    less could fail (unless we want to request getatr and setatr
 578          *    permissions (only).  At least for POSIX we do not have to
 579          *    request so much.
 580          */
 581         unsigned oflags = O_EXCL | O_CREAT | O_RDWR;
 582         struct tcon_link *tlink;
 583         struct cifs_tcon *tcon;
 584         struct TCP_Server_Info *server;
 585         struct cifs_fid fid;
 586         __u32 oplock;
 587
 588         cifs_dbg(FYI, "cifs_create parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
 589                  inode, direntry, direntry);
 590
 591         tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));
 592         rc = PTR_ERR(tlink);
 593         if (IS_ERR(tlink))
 594                 goto out_free_xid;
 595
 596         tcon = tlink_tcon(tlink);
 597         server = tcon->ses->server;
 598
 599         if (server->ops->new_lease_key)
 600                 server->ops->new_lease_key(&fid);
 601
 602         rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode,
 603                             &oplock, &fid);
 604         if (!rc && server->ops->close)
 605                 server->ops->close(xid, tcon, &fid);
 606
 607         cifs_put_tlink(tlink);
 608 out_free_xid:
 609         free_xid(xid);
 610         return rc;
 611 }
 612
 613 int cifs_mknod(struct inode *inode, struct dentry *direntry, umode_t mode,
 614                 dev_t device_number)
 615 {
 616         int rc = -EPERM;
 617         unsigned int xid;
 618         int create_options = CREATE_NOT_DIR | CREATE_OPTION_SPECIAL;
 619         struct cifs_sb_info *cifs_sb;
 620         struct tcon_link *tlink;
 621         struct cifs_tcon *tcon;
 622         struct cifs_io_parms io_parms;
 623         char *full_path = NULL;
 624         struct inode *newinode = NULL;
 625         __u32 oplock = 0;
 626         struct cifs_fid fid;
 627         struct cifs_open_parms oparms;
 628         FILE_ALL_INFO *buf = NULL;
 629         unsigned int bytes_written;
 630         struct win_dev *pdev;
 631         struct kvec iov[2];
 632
 633         if (!old_valid_dev(device_number))
 634                 return -EINVAL;
 635
 636         cifs_sb = CIFS_SB(inode->i_sb);
 637         tlink = cifs_sb_tlink(cifs_sb);
 638         if (IS_ERR(tlink))
 639                 return PTR_ERR(tlink);
 640
 641         tcon = tlink_tcon(tlink);
 642
 643         xid = get_xid();
 644
 645         full_path = build_path_from_dentry(direntry);
 646         if (full_path == NULL) {
 647                 rc = -ENOMEM;
 648                 goto mknod_out;
 649         }
 650
 651         if (tcon->unix_ext) {
 652                 struct cifs_unix_set_info_args args = {
 653                         .mode   = mode & ~current_umask(),
 654                         .ctime  = NO_CHANGE_64,
 655                         .atime  = NO_CHANGE_64,
 656                         .mtime  = NO_CHANGE_64,
 657                         .device = device_number,
 658                 };
 659                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
 660                         args.uid = current_fsuid();
 661                         args.gid = current_fsgid();
 662                 } else {
 663                         args.uid = INVALID_UID; /* no change */
 664                         args.gid = INVALID_GID; /* no change */
 665                 }
 666                 rc = CIFSSMBUnixSetPathInfo(xid, tcon, full_path, &args,
 667                                             cifs_sb->local_nls,
 668                                             cifs_remap(cifs_sb));
 669                 if (rc)
 670                         goto mknod_out;
 671
 672                 rc = cifs_get_inode_info_unix(&newinode, full_path,
 673                                                 inode->i_sb, xid);
 674
 675                 if (rc == 0)
 676                         d_instantiate(direntry, newinode);
 677                 goto mknod_out;
 678         }
 679
 680         if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL))
 681                 goto mknod_out;
 682
 683
 684         cifs_dbg(FYI, "sfu compat create special file\n");
 685
 686         buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
 687         if (buf == NULL) {
 688                 kfree(full_path);
 689                 rc = -ENOMEM;
 690                 free_xid(xid);
 691                 return rc;
 692         }
 693
 694         if (backup_cred(cifs_sb))
 695                 create_options |= CREATE_OPEN_BACKUP_INTENT;
 696
 697         oparms.tcon = tcon;
 698         oparms.cifs_sb = cifs_sb;
 699         oparms.desired_access = GENERIC_WRITE;
 700         oparms.create_options = create_options;
 701         oparms.disposition = FILE_CREATE;
 702         oparms.path = full_path;
 703         oparms.fid = &fid;
 704         oparms.reconnect = false;
 705
 706         if (tcon->ses->server->oplocks)
 707                 oplock = REQ_OPLOCK;
 708         else
 709                 oplock = 0;
 710         rc = tcon->ses->server->ops->open(xid, &oparms, &oplock, buf);
 711         if (rc)
 712                 goto mknod_out;
 713
 714         /*
 715          * BB Do not bother to decode buf since no local inode yet to put
 716          * timestamps in, but we can reuse it safely.
 717          */
 718
 719         pdev = (struct win_dev *)buf;
 720         io_parms.pid = current->tgid;
 721         io_parms.tcon = tcon;
 722         io_parms.offset = 0;
 723         io_parms.length = sizeof(struct win_dev);
 724         iov[1].iov_base = buf;
 725         iov[1].iov_len = sizeof(struct win_dev);
 726         if (S_ISCHR(mode)) {
 727                 memcpy(pdev->type, "IntxCHR", 8);
 728                 pdev->major = cpu_to_le64(MAJOR(device_number));
 729                 pdev->minor = cpu_to_le64(MINOR(device_number));
 730                 rc = tcon->ses->server->ops->sync_write(xid, &fid, &io_parms,
 731                                                         &bytes_written, iov, 1);
 732         } else if (S_ISBLK(mode)) {
 733                 memcpy(pdev->type, "IntxBLK", 8);
 734                 pdev->major = cpu_to_le64(MAJOR(device_number));
 735                 pdev->minor = cpu_to_le64(MINOR(device_number));
 736                 rc = tcon->ses->server->ops->sync_write(xid, &fid, &io_parms,
 737                                                         &bytes_written, iov, 1);
 738         } /* else if (S_ISFIFO) */
 739         tcon->ses->server->ops->close(xid, tcon, &fid);
 740         d_drop(direntry);
 741
 742         /* FIXME: add code here to set EAs */
 743
 744 mknod_out:
 745         kfree(full_path);
 746         kfree(buf);
 747         free_xid(xid);
 748         cifs_put_tlink(tlink);
 749         return rc;
 750 }
 751
 752 struct dentry *
 753 cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,
 754             unsigned int flags)
 755 {
 756         unsigned int xid;
 757         int rc = 0; /* to get around spurious gcc warning, set to zero here */
 758         struct cifs_sb_info *cifs_sb;
 759         struct tcon_link *tlink;
 760         struct cifs_tcon *pTcon;
 761         struct inode *newInode = NULL;
 762         char *full_path = NULL;
 763
 764         xid = get_xid();
 765
 766         cifs_dbg(FYI, "parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
 767                  parent_dir_inode, direntry, direntry);
 768
 769         /* check whether path exists */
 770
 771         cifs_sb = CIFS_SB(parent_dir_inode->i_sb);
 772         tlink = cifs_sb_tlink(cifs_sb);
 773         if (IS_ERR(tlink)) {
 774                 free_xid(xid);
 775                 return (struct dentry *)tlink;
 776         }
 777         pTcon = tlink_tcon(tlink);
 778
 779         rc = check_name(direntry);
 780         if (rc)
 781                 goto lookup_out;
 782
 783         /* can not grab the rename sem here since it would
 784         deadlock in the cases (beginning of sys_rename itself)
 785         in which we already have the sb rename sem */
 786         full_path = build_path_from_dentry(direntry);
 787         if (full_path == NULL) {
 788                 rc = -ENOMEM;
 789                 goto lookup_out;
 790         }
 791
 792         if (d_really_is_positive(direntry)) {
 793                 cifs_dbg(FYI, "non-NULL inode in lookup\n");
 794         } else {
 795                 cifs_dbg(FYI, "NULL inode in lookup\n");
 796         }
 797         cifs_dbg(FYI, "Full path: %s inode = 0x%p\n",
 798                  full_path, d_inode(direntry));
 799
 800         if (pTcon->unix_ext) {
 801                 rc = cifs_get_inode_info_unix(&newInode, full_path,
 802                                               parent_dir_inode->i_sb, xid);
 803         } else {
 804                 rc = cifs_get_inode_info(&newInode, full_path, NULL,
 805                                 parent_dir_inode->i_sb, xid, NULL);
 806         }
 807
 808         if ((rc == 0) && (newInode != NULL)) {
 809                 d_add(direntry, newInode);
 810                 /* since paths are not looked up by component - the parent
 811                    directories are presumed to be good here */
 812                 renew_parental_timestamps(direntry);
 813
 814         } else if (rc == -ENOENT) {
 815                 rc = 0;
 816                 cifs_set_time(direntry, jiffies);
 817                 d_add(direntry, NULL);
 818         /*      if it was once a directory (but how can we tell?) we could do
 819                 shrink_dcache_parent(direntry); */
 820         } else if (rc != -EACCES) {
 821                 cifs_dbg(FYI, "Unexpected lookup error %d\n", rc);
 822                 /* We special case check for Access Denied - since that
 823                 is a common return code */
 824         }
 825
 826 lookup_out:
 827         kfree(full_path);
 828         cifs_put_tlink(tlink);
 829         free_xid(xid);
 830         return ERR_PTR(rc);
 831 }
 832
 833 static int
 834 cifs_d_revalidate(struct dentry *direntry, unsigned int flags)
 835 {
 836         if (flags & LOOKUP_RCU)
 837                 return -ECHILD;
 838
 839         if (d_really_is_positive(direntry)) {
 840                 if (cifs_revalidate_dentry(direntry))
 841                         return 0;
 842                 else {
 843                         /*
 844                          * If the inode wasn't known to be a dfs entry when
 845                          * the dentry was instantiated, such as when created
 846                          * via ->readdir(), it needs to be set now since the
 847                          * attributes will have been updated by
 848                          * cifs_revalidate_dentry().
 849                          */
 850                         if (IS_AUTOMOUNT(d_inode(direntry)) &&
 851                            !(direntry->d_flags & DCACHE_NEED_AUTOMOUNT)) {
 852                                 spin_lock(&direntry->d_lock);
 853                                 direntry->d_flags |= DCACHE_NEED_AUTOMOUNT;
 854                                 spin_unlock(&direntry->d_lock);
 855                         }
 856
 857                         return 1;
 858                 }
 859         }
 860
 861         /*
 862          * This may be nfsd (or something), anyway, we can't see the
 863          * intent of this. So, since this can be for creation, drop it.
 864          */
 865         if (!flags)
 866                 return 0;
 867
 868         /*
 869          * Drop the negative dentry, in order to make sure to use the
 870          * case sensitive name which is specified by user if this is
 871          * for creation.
 872          */
 873         if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))
 874                 return 0;
 875
 876         if (time_after(jiffies, cifs_get_time(direntry) + HZ) || !lookupCacheEnabled)
 877                 return 0;
 878
 879         return 1;
 880 }
 881
 882 /* static int cifs_d_delete(struct dentry *direntry)
 883 {
 884         int rc = 0;
 885
 886         cifs_dbg(FYI, "In cifs d_delete, name = %pd\n", direntry);
 887
 888         return rc;
 889 }     */
 890
 891 const struct dentry_operations cifs_dentry_ops = {
 892         .d_revalidate = cifs_d_revalidate,
 893         .d_automount = cifs_dfs_d_automount,
 894 /* d_delete:       cifs_d_delete,      */ /* not needed except for debugging */
 895 };
 896
 897 static int cifs_ci_hash(const struct dentry *dentry, struct qstr *q)
 898 {
 899         struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;
 900         unsigned long hash;
 901         wchar_t c;
 902         int i, charlen;
 903
 904         hash = init_name_hash(dentry);
 905         for (i = 0; i < q->len; i += charlen) {
 906                 charlen = codepage->char2uni(&q->name[i], q->len - i, &c);
 907                 /* error out if we can't convert the character */
 908                 if (unlikely(charlen < 0))
 909                         return charlen;
 910                 hash = partial_name_hash(cifs_toupper(c), hash);
 911         }
 912         q->hash = end_name_hash(hash);
 913
 914         return 0;
 915 }
 916
 917 static int cifs_ci_compare(const struct dentry *dentry,
 918                 unsigned int len, const char *str, const struct qstr *name)
 919 {
 920         struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;
 921         wchar_t c1, c2;
 922         int i, l1, l2;
 923
 924         /*
 925          * We make the assumption here that uppercase characters in the local
 926          * codepage are always the same length as their lowercase counterparts.
 927          *
 928          * If that's ever not the case, then this will fail to match it.
 929          */
 930         if (name->len != len)
 931                 return 1;
 932
 933         for (i = 0; i < len; i += l1) {
 934                 /* Convert characters in both strings to UTF-16. */
 935                 l1 = codepage->char2uni(&str[i], len - i, &c1);
 936                 l2 = codepage->char2uni(&name->name[i], name->len - i, &c2);
 937
 938                 /*
 939                  * If we can't convert either character, just declare it to
 940                  * be 1 byte long and compare the original byte.
 941                  */
 942                 if (unlikely(l1 < 0 && l2 < 0)) {
 943                         if (str[i] != name->name[i])
 944                                 return 1;
 945                         l1 = 1;
 946                         continue;
 947                 }
 948
 949                 /*
 950                  * Here, we again ass|u|me that upper/lowercase versions of
 951                  * a character are the same length in the local NLS.
 952                  */
 953                 if (l1 != l2)
 954                         return 1;
 955
 956                 /* Now compare uppercase versions of these characters */
 957                 if (cifs_toupper(c1) != cifs_toupper(c2))
 958                         return 1;
 959         }
 960
 961         return 0;
 962 }
 963
 964 const struct dentry_operations cifs_ci_dentry_ops = {
 965         .d_revalidate = cifs_d_revalidate,
 966         .d_hash = cifs_ci_hash,
 967         .d_compare = cifs_ci_compare,
 968         .d_automount = cifs_dfs_d_automount,
 969 };