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] = dirsep;
 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(tcon->fsAttrInfo.MaxPathNameComponentLength &&
 208                      direntry->d_name.len >
 209                      le32_to_cpu(tcon->fsAttrInfo.MaxPathNameComponentLength)))
 210                 return -ENAMETOOLONG;
 211
 212         if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS)) {
 213                 for (i = 0; i < direntry->d_name.len; i++) {
 214                         if (direntry->d_name.name[i] == '\\') {
 215                                 cifs_dbg(FYI, "Invalid file name\n");
 216                                 return -EINVAL;
 217                         }
 218                 }
 219         }
 220         return 0;
 221 }
 222
 223
 224 /* Inode operations in similar order to how they appear in Linux file fs.h */
 225
 226 static int
 227 cifs_do_create(struct inode *inode, struct dentry *direntry, unsigned int xid,
 228                struct tcon_link *tlink, unsigned oflags, umode_t mode,
 229                __u32 *oplock, struct cifs_fid *fid)
 230 {
 231         int rc = -ENOENT;
 232         int create_options = CREATE_NOT_DIR;
 233         int desired_access;
 234         struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
 235         struct cifs_tcon *tcon = tlink_tcon(tlink);
 236         char *full_path = NULL;
 237         FILE_ALL_INFO *buf = NULL;
 238         struct inode *newinode = NULL;
 239         int disposition;
 240         struct TCP_Server_Info *server = tcon->ses->server;
 241         struct cifs_open_parms oparms;
 242
 243         *oplock = 0;
 244         if (tcon->ses->server->oplocks)
 245                 *oplock = REQ_OPLOCK;
 246
 247         full_path = build_path_from_dentry(direntry);
 248         if (full_path == NULL) {
 249                 rc = -ENOMEM;
 250                 goto out;
 251         }
 252
 253         if (tcon->unix_ext && cap_unix(tcon->ses) && !tcon->broken_posix_open &&
 254             (CIFS_UNIX_POSIX_PATH_OPS_CAP &
 255                         le64_to_cpu(tcon->fsUnixInfo.Capability))) {
 256                 rc = cifs_posix_open(full_path, &newinode, inode->i_sb, mode,
 257                                      oflags, oplock, &fid->netfid, xid);
 258                 switch (rc) {
 259                 case 0:
 260                         if (newinode == NULL) {
 261                                 /* query inode info */
 262                                 goto cifs_create_get_file_info;
 263                         }
 264
 265                         if (S_ISDIR(newinode->i_mode)) {
 266                                 CIFSSMBClose(xid, tcon, fid->netfid);
 267                                 iput(newinode);
 268                                 rc = -EISDIR;
 269                                 goto out;
 270                         }
 271
 272                         if (!S_ISREG(newinode->i_mode)) {
 273                                 /*
 274                                  * The server may allow us to open things like
 275                                  * FIFOs, but the client isn't set up to deal
 276                                  * with that. If it's not a regular file, just
 277                                  * close it and proceed as if it were a normal
 278                                  * lookup.
 279                                  */
 280                                 CIFSSMBClose(xid, tcon, fid->netfid);
 281                                 goto cifs_create_get_file_info;
 282                         }
 283                         /* success, no need to query */
 284                         goto cifs_create_set_dentry;
 285
 286                 case -ENOENT:
 287                         goto cifs_create_get_file_info;
 288
 289                 case -EIO:
 290                 case -EINVAL:
 291                         /*
 292                          * EIO could indicate that (posix open) operation is not
 293                          * supported, despite what server claimed in capability
 294                          * negotiation.
 295                          *
 296                          * POSIX open in samba versions 3.3.1 and earlier could
 297                          * incorrectly fail with invalid parameter.
 298                          */
 299                         tcon->broken_posix_open = true;
 300                         break;
 301
 302                 case -EREMOTE:
 303                 case -EOPNOTSUPP:
 304                         /*
 305                          * EREMOTE indicates DFS junction, which is not handled
 306                          * in posix open.  If either that or op not supported
 307                          * returned, follow the normal lookup.
 308                          */
 309                         break;
 310
 311                 default:
 312                         goto out;
 313                 }
 314                 /*
 315                  * fallthrough to retry, using older open call, this is case
 316                  * where server does not support this SMB level, and falsely
 317                  * claims capability (also get here for DFS case which should be
 318                  * rare for path not covered on files)
 319                  */
 320         }
 321
 322         desired_access = 0;
 323         if (OPEN_FMODE(oflags) & FMODE_READ)
 324                 desired_access |= GENERIC_READ; /* is this too little? */
 325         if (OPEN_FMODE(oflags) & FMODE_WRITE)
 326                 desired_access |= GENERIC_WRITE;
 327
 328         disposition = FILE_OVERWRITE_IF;
 329         if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
 330                 disposition = FILE_CREATE;
 331         else if ((oflags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))
 332                 disposition = FILE_OVERWRITE_IF;
 333         else if ((oflags & O_CREAT) == O_CREAT)
 334                 disposition = FILE_OPEN_IF;
 335         else
 336                 cifs_dbg(FYI, "Create flag not set in create function\n");
 337
 338         /*
 339          * BB add processing to set equivalent of mode - e.g. via CreateX with
 340          * ACLs
 341          */
 342
 343         if (!server->ops->open) {
 344                 rc = -ENOSYS;
 345                 goto out;
 346         }
 347
 348         buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
 349         if (buf == NULL) {
 350                 rc = -ENOMEM;
 351                 goto out;
 352         }
 353
 354         /*
 355          * if we're not using unix extensions, see if we need to set
 356          * ATTR_READONLY on the create call
 357          */
 358         if (!tcon->unix_ext && (mode & S_IWUGO) == 0)
 359                 create_options |= CREATE_OPTION_READONLY;
 360
 361         if (backup_cred(cifs_sb))
 362                 create_options |= CREATE_OPEN_BACKUP_INTENT;
 363
 364         oparms.tcon = tcon;
 365         oparms.cifs_sb = cifs_sb;
 366         oparms.desired_access = desired_access;
 367         oparms.create_options = create_options;
 368         oparms.disposition = disposition;
 369         oparms.path = full_path;
 370         oparms.fid = fid;
 371         oparms.reconnect = false;
 372         oparms.mode = mode;
 373         rc = server->ops->open(xid, &oparms, oplock, buf);
 374         if (rc) {
 375                 cifs_dbg(FYI, "cifs_create returned 0x%x\n", rc);
 376                 goto out;
 377         }
 378
 379         /*
 380          * If Open reported that we actually created a file then we now have to
 381          * set the mode if possible.
 382          */
 383         if ((tcon->unix_ext) && (*oplock & CIFS_CREATE_ACTION)) {
 384                 struct cifs_unix_set_info_args args = {
 385                                 .mode   = mode,
 386                                 .ctime  = NO_CHANGE_64,
 387                                 .atime  = NO_CHANGE_64,
 388                                 .mtime  = NO_CHANGE_64,
 389                                 .device = 0,
 390                 };
 391
 392                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
 393                         args.uid = current_fsuid();
 394                         if (inode->i_mode & S_ISGID)
 395                                 args.gid = inode->i_gid;
 396                         else
 397                                 args.gid = current_fsgid();
 398                 } else {
 399                         args.uid = INVALID_UID; /* no change */
 400                         args.gid = INVALID_GID; /* no change */
 401                 }
 402                 CIFSSMBUnixSetFileInfo(xid, tcon, &args, fid->netfid,
 403                                        current->tgid);
 404         } else {
 405                 /*
 406                  * BB implement mode setting via Windows security
 407                  * descriptors e.g.
 408                  */
 409                 /* CIFSSMBWinSetPerms(xid,tcon,path,mode,-1,-1,nls);*/
 410
 411                 /* Could set r/o dos attribute if mode & 0222 == 0 */
 412         }
 413
 414 cifs_create_get_file_info:
 415         /* server might mask mode so we have to query for it */
 416         if (tcon->unix_ext)
 417                 rc = cifs_get_inode_info_unix(&newinode, full_path, inode->i_sb,
 418                                               xid);
 419         else {
 420                 rc = cifs_get_inode_info(&newinode, full_path, buf, inode->i_sb,
 421                                          xid, fid);
 422                 if (newinode) {
 423                         if (server->ops->set_lease_key)
 424                                 server->ops->set_lease_key(newinode, fid);
 425                         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DYNPERM)
 426                                 newinode->i_mode = mode;
 427                         if ((*oplock & CIFS_CREATE_ACTION) &&
 428                             (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID)) {
 429                                 newinode->i_uid = current_fsuid();
 430                                 if (inode->i_mode & S_ISGID)
 431                                         newinode->i_gid = inode->i_gid;
 432                                 else
 433                                         newinode->i_gid = current_fsgid();
 434                         }
 435                 }
 436         }
 437
 438 cifs_create_set_dentry:
 439         if (rc != 0) {
 440                 cifs_dbg(FYI, "Create worked, get_inode_info failed rc = %d\n",
 441                          rc);
 442                 goto out_err;
 443         }
 444
 445         if (S_ISDIR(newinode->i_mode)) {
 446                 rc = -EISDIR;
 447                 goto out_err;
 448         }
 449
 450         d_drop(direntry);
 451         d_add(direntry, newinode);
 452
 453 out:
 454         kfree(buf);
 455         kfree(full_path);
 456         return rc;
 457
 458 out_err:
 459         if (server->ops->close)
 460                 server->ops->close(xid, tcon, fid);
 461         if (newinode)
 462                 iput(newinode);
 463         goto out;
 464 }
 465
 466 int
 467 cifs_atomic_open(struct inode *inode, struct dentry *direntry,
 468                  struct file *file, unsigned oflags, umode_t mode)
 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;
 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                 file->f_mode |= FMODE_CREATED;
 542
 543         rc = finish_open(file, direntry, generic_file_open);
 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 (!S_ISCHR(mode) && !S_ISBLK(mode))
 687                 goto mknod_out;
 688
 689         if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL))
 690                 goto mknod_out;
 691
 692
 693         cifs_dbg(FYI, "sfu compat create special file\n");
 694
 695         buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
 696         if (buf == NULL) {
 697                 rc = -ENOMEM;
 698                 goto mknod_out;
 699         }
 700
 701         if (backup_cred(cifs_sb))
 702                 create_options |= CREATE_OPEN_BACKUP_INTENT;
 703
 704         oparms.tcon = tcon;
 705         oparms.cifs_sb = cifs_sb;
 706         oparms.desired_access = GENERIC_WRITE;
 707         oparms.create_options = create_options;
 708         oparms.disposition = FILE_CREATE;
 709         oparms.path = full_path;
 710         oparms.fid = &fid;
 711         oparms.reconnect = false;
 712
 713         if (tcon->ses->server->oplocks)
 714                 oplock = REQ_OPLOCK;
 715         else
 716                 oplock = 0;
 717         rc = tcon->ses->server->ops->open(xid, &oparms, &oplock, buf);
 718         if (rc)
 719                 goto mknod_out;
 720
 721         /*
 722          * BB Do not bother to decode buf since no local inode yet to put
 723          * timestamps in, but we can reuse it safely.
 724          */
 725
 726         pdev = (struct win_dev *)buf;
 727         io_parms.pid = current->tgid;
 728         io_parms.tcon = tcon;
 729         io_parms.offset = 0;
 730         io_parms.length = sizeof(struct win_dev);
 731         iov[1].iov_base = buf;
 732         iov[1].iov_len = sizeof(struct win_dev);
 733         if (S_ISCHR(mode)) {
 734                 memcpy(pdev->type, "IntxCHR", 8);
 735                 pdev->major = cpu_to_le64(MAJOR(device_number));
 736                 pdev->minor = cpu_to_le64(MINOR(device_number));
 737                 rc = tcon->ses->server->ops->sync_write(xid, &fid, &io_parms,
 738                                                         &bytes_written, iov, 1);
 739         } else if (S_ISBLK(mode)) {
 740                 memcpy(pdev->type, "IntxBLK", 8);
 741                 pdev->major = cpu_to_le64(MAJOR(device_number));
 742                 pdev->minor = cpu_to_le64(MINOR(device_number));
 743                 rc = tcon->ses->server->ops->sync_write(xid, &fid, &io_parms,
 744                                                         &bytes_written, iov, 1);
 745         }
 746         tcon->ses->server->ops->close(xid, tcon, &fid);
 747         d_drop(direntry);
 748
 749         /* FIXME: add code here to set EAs */
 750
 751 mknod_out:
 752         kfree(full_path);
 753         kfree(buf);
 754         free_xid(xid);
 755         cifs_put_tlink(tlink);
 756         return rc;
 757 }
 758
 759 struct dentry *
 760 cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,
 761             unsigned int flags)
 762 {
 763         unsigned int xid;
 764         int rc = 0; /* to get around spurious gcc warning, set to zero here */
 765         struct cifs_sb_info *cifs_sb;
 766         struct tcon_link *tlink;
 767         struct cifs_tcon *pTcon;
 768         struct inode *newInode = NULL;
 769         char *full_path = NULL;
 770
 771         xid = get_xid();
 772
 773         cifs_dbg(FYI, "parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
 774                  parent_dir_inode, direntry, direntry);
 775
 776         /* check whether path exists */
 777
 778         cifs_sb = CIFS_SB(parent_dir_inode->i_sb);
 779         tlink = cifs_sb_tlink(cifs_sb);
 780         if (IS_ERR(tlink)) {
 781                 free_xid(xid);
 782                 return ERR_CAST(tlink);
 783         }
 784         pTcon = tlink_tcon(tlink);
 785
 786         rc = check_name(direntry, pTcon);
 787         if (unlikely(rc)) {
 788                 cifs_put_tlink(tlink);
 789                 free_xid(xid);
 790                 return ERR_PTR(rc);
 791         }
 792
 793         /* can not grab the rename sem here since it would
 794         deadlock in the cases (beginning of sys_rename itself)
 795         in which we already have the sb rename sem */
 796         full_path = build_path_from_dentry(direntry);
 797         if (full_path == NULL) {
 798                 cifs_put_tlink(tlink);
 799                 free_xid(xid);
 800                 return ERR_PTR(-ENOMEM);
 801         }
 802
 803         if (d_really_is_positive(direntry)) {
 804                 cifs_dbg(FYI, "non-NULL inode in lookup\n");
 805         } else {
 806                 cifs_dbg(FYI, "NULL inode in lookup\n");
 807         }
 808         cifs_dbg(FYI, "Full path: %s inode = 0x%p\n",
 809                  full_path, d_inode(direntry));
 810
 811         if (pTcon->unix_ext) {
 812                 rc = cifs_get_inode_info_unix(&newInode, full_path,
 813                                               parent_dir_inode->i_sb, xid);
 814         } else {
 815                 rc = cifs_get_inode_info(&newInode, full_path, NULL,
 816                                 parent_dir_inode->i_sb, xid, NULL);
 817         }
 818
 819         if (rc == 0) {
 820                 /* since paths are not looked up by component - the parent
 821                    directories are presumed to be good here */
 822                 renew_parental_timestamps(direntry);
 823         } else if (rc == -ENOENT) {
 824                 cifs_set_time(direntry, jiffies);
 825                 newInode = NULL;
 826         } else {
 827                 if (rc != -EACCES) {
 828                         cifs_dbg(FYI, "Unexpected lookup error %d\n", rc);
 829                         /* We special case check for Access Denied - since that
 830                         is a common return code */
 831                 }
 832                 newInode = ERR_PTR(rc);
 833         }
 834         kfree(full_path);
 835         cifs_put_tlink(tlink);
 836         free_xid(xid);
 837         return d_splice_alias(newInode, direntry);
 838 }
 839
 840 static int
 841 cifs_d_revalidate(struct dentry *direntry, unsigned int flags)
 842 {
 843         if (flags & LOOKUP_RCU)
 844                 return -ECHILD;
 845
 846         if (d_really_is_positive(direntry)) {
 847                 if (cifs_revalidate_dentry(direntry))
 848                         return 0;
 849                 else {
 850                         /*
 851                          * If the inode wasn't known to be a dfs entry when
 852                          * the dentry was instantiated, such as when created
 853                          * via ->readdir(), it needs to be set now since the
 854                          * attributes will have been updated by
 855                          * cifs_revalidate_dentry().
 856                          */
 857                         if (IS_AUTOMOUNT(d_inode(direntry)) &&
 858                            !(direntry->d_flags & DCACHE_NEED_AUTOMOUNT)) {
 859                                 spin_lock(&direntry->d_lock);
 860                                 direntry->d_flags |= DCACHE_NEED_AUTOMOUNT;
 861                                 spin_unlock(&direntry->d_lock);
 862                         }
 863
 864                         return 1;
 865                 }
 866         }
 867
 868         /*
 869          * This may be nfsd (or something), anyway, we can't see the
 870          * intent of this. So, since this can be for creation, drop it.
 871          */
 872         if (!flags)
 873                 return 0;
 874
 875         /*
 876          * Drop the negative dentry, in order to make sure to use the
 877          * case sensitive name which is specified by user if this is
 878          * for creation.
 879          */
 880         if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))
 881                 return 0;
 882
 883         if (time_after(jiffies, cifs_get_time(direntry) + HZ) || !lookupCacheEnabled)
 884                 return 0;
 885
 886         return 1;
 887 }
 888
 889 /* static int cifs_d_delete(struct dentry *direntry)
 890 {
 891         int rc = 0;
 892
 893         cifs_dbg(FYI, "In cifs d_delete, name = %pd\n", direntry);
 894
 895         return rc;
 896 }     */
 897
 898 const struct dentry_operations cifs_dentry_ops = {
 899         .d_revalidate = cifs_d_revalidate,
 900         .d_automount = cifs_dfs_d_automount,
 901 /* d_delete:       cifs_d_delete,      */ /* not needed except for debugging */
 902 };
 903
 904 static int cifs_ci_hash(const struct dentry *dentry, struct qstr *q)
 905 {
 906         struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;
 907         unsigned long hash;
 908         wchar_t c;
 909         int i, charlen;
 910
 911         hash = init_name_hash(dentry);
 912         for (i = 0; i < q->len; i += charlen) {
 913                 charlen = codepage->char2uni(&q->name[i], q->len - i, &c);
 914                 /* error out if we can't convert the character */
 915                 if (unlikely(charlen < 0))
 916                         return charlen;
 917                 hash = partial_name_hash(cifs_toupper(c), hash);
 918         }
 919         q->hash = end_name_hash(hash);
 920
 921         return 0;
 922 }
 923
 924 static int cifs_ci_compare(const struct dentry *dentry,
 925                 unsigned int len, const char *str, const struct qstr *name)
 926 {
 927         struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;
 928         wchar_t c1, c2;
 929         int i, l1, l2;
 930
 931         /*
 932          * We make the assumption here that uppercase characters in the local
 933          * codepage are always the same length as their lowercase counterparts.
 934          *
 935          * If that's ever not the case, then this will fail to match it.
 936          */
 937         if (name->len != len)
 938                 return 1;
 939
 940         for (i = 0; i < len; i += l1) {
 941                 /* Convert characters in both strings to UTF-16. */
 942                 l1 = codepage->char2uni(&str[i], len - i, &c1);
 943                 l2 = codepage->char2uni(&name->name[i], name->len - i, &c2);
 944
 945                 /*
 946                  * If we can't convert either character, just declare it to
 947                  * be 1 byte long and compare the original byte.
 948                  */
 949                 if (unlikely(l1 < 0 && l2 < 0)) {
 950                         if (str[i] != name->name[i])
 951                                 return 1;
 952                         l1 = 1;
 953                         continue;
 954                 }
 955
 956                 /*
 957                  * Here, we again ass|u|me that upper/lowercase versions of
 958                  * a character are the same length in the local NLS.
 959                  */
 960                 if (l1 != l2)
 961                         return 1;
 962
 963                 /* Now compare uppercase versions of these characters */
 964                 if (cifs_toupper(c1) != cifs_toupper(c2))
 965                         return 1;
 966         }
 967
 968         return 0;
 969 }
 970
 971 const struct dentry_operations cifs_ci_dentry_ops = {
 972         .d_revalidate = cifs_d_revalidate,
 973         .d_hash = cifs_ci_hash,
 974         .d_compare = cifs_ci_compare,
 975         .d_automount = cifs_dfs_d_automount,
 976 };