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