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(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                  int *opened)
 470 {
 471         int rc;
 472         unsigned int xid;
 473         struct tcon_link *tlink;
 474         struct cifs_tcon *tcon;
 475         struct TCP_Server_Info *server;
 476         struct cifs_fid fid;
 477         struct cifs_pending_open open;
 478         __u32 oplock;
 479         struct cifsFileInfo *file_info;
 480
 481         /*
 482          * Posix open is only called (at lookup time) for file create now. For
 483          * opens (rather than creates), because we do not know if it is a file
 484          * or directory yet, and current Samba no longer allows us to do posix
 485          * open on dirs, we could end up wasting an open call on what turns out
 486          * to be a dir. For file opens, we wait to call posix open till
 487          * cifs_open.  It could be added to atomic_open in the future but the
 488          * performance tradeoff of the extra network request when EISDIR or
 489          * EACCES is returned would have to be weighed against the 50% reduction
 490          * in network traffic in the other paths.
 491          */
 492         if (!(oflags & O_CREAT)) {
 493                 struct dentry *res;
 494
 495                 /*
 496                  * Check for hashed negative dentry. We have already revalidated
 497                  * the dentry and it is fine. No need to perform another lookup.
 498                  */
 499                 if (!d_in_lookup(direntry))
 500                         return -ENOENT;
 501
 502                 res = cifs_lookup(inode, direntry, 0);
 503                 if (IS_ERR(res))
 504                         return PTR_ERR(res);
 505
 506                 return finish_no_open(file, res);
 507         }
 508
 509         xid = get_xid();
 510
 511         cifs_dbg(FYI, "parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
 512                  inode, direntry, direntry);
 513
 514         tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));
 515         if (IS_ERR(tlink)) {
 516                 rc = PTR_ERR(tlink);
 517                 goto out_free_xid;
 518         }
 519
 520         tcon = tlink_tcon(tlink);
 521
 522         rc = check_name(direntry, tcon);
 523         if (rc)
 524                 goto out;
 525
 526         server = tcon->ses->server;
 527
 528         if (server->ops->new_lease_key)
 529                 server->ops->new_lease_key(&fid);
 530
 531         cifs_add_pending_open(&fid, tlink, &open);
 532
 533         rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode,
 534                             &oplock, &fid);
 535
 536         if (rc) {
 537                 cifs_del_pending_open(&open);
 538                 goto out;
 539         }
 540
 541         if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
 542                 *opened |= FILE_CREATED;
 543
 544         rc = finish_open(file, direntry, generic_file_open, opened);
 545         if (rc) {
 546                 if (server->ops->close)
 547                         server->ops->close(xid, tcon, &fid);
 548                 cifs_del_pending_open(&open);
 549                 goto out;
 550         }
 551
 552         if (file->f_flags & O_DIRECT &&
 553             CIFS_SB(inode->i_sb)->mnt_cifs_flags & CIFS_MOUNT_STRICT_IO) {
 554                 if (CIFS_SB(inode->i_sb)->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
 555                         file->f_op = &cifs_file_direct_nobrl_ops;
 556                 else
 557                         file->f_op = &cifs_file_direct_ops;
 558                 }
 559
 560         file_info = cifs_new_fileinfo(&fid, file, tlink, oplock);
 561         if (file_info == NULL) {
 562                 if (server->ops->close)
 563                         server->ops->close(xid, tcon, &fid);
 564                 cifs_del_pending_open(&open);
 565                 fput(file);
 566                 rc = -ENOMEM;
 567         }
 568
 569 out:
 570         cifs_put_tlink(tlink);
 571 out_free_xid:
 572         free_xid(xid);
 573         return rc;
 574 }
 575
 576 int cifs_create(struct inode *inode, struct dentry *direntry, umode_t mode,
 577                 bool excl)
 578 {
 579         int rc;
 580         unsigned int xid = get_xid();
 581         /*
 582          * BB below access is probably too much for mknod to request
 583          *    but we have to do query and setpathinfo so requesting
 584          *    less could fail (unless we want to request getatr and setatr
 585          *    permissions (only).  At least for POSIX we do not have to
 586          *    request so much.
 587          */
 588         unsigned oflags = O_EXCL | O_CREAT | O_RDWR;
 589         struct tcon_link *tlink;
 590         struct cifs_tcon *tcon;
 591         struct TCP_Server_Info *server;
 592         struct cifs_fid fid;
 593         __u32 oplock;
 594
 595         cifs_dbg(FYI, "cifs_create parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
 596                  inode, direntry, direntry);
 597
 598         tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));
 599         rc = PTR_ERR(tlink);
 600         if (IS_ERR(tlink))
 601                 goto out_free_xid;
 602
 603         tcon = tlink_tcon(tlink);
 604         server = tcon->ses->server;
 605
 606         if (server->ops->new_lease_key)
 607                 server->ops->new_lease_key(&fid);
 608
 609         rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode,
 610                             &oplock, &fid);
 611         if (!rc && server->ops->close)
 612                 server->ops->close(xid, tcon, &fid);
 613
 614         cifs_put_tlink(tlink);
 615 out_free_xid:
 616         free_xid(xid);
 617         return rc;
 618 }
 619
 620 int cifs_mknod(struct inode *inode, struct dentry *direntry, umode_t mode,
 621                 dev_t device_number)
 622 {
 623         int rc = -EPERM;
 624         unsigned int xid;
 625         int create_options = CREATE_NOT_DIR | CREATE_OPTION_SPECIAL;
 626         struct cifs_sb_info *cifs_sb;
 627         struct tcon_link *tlink;
 628         struct cifs_tcon *tcon;
 629         struct cifs_io_parms io_parms;
 630         char *full_path = NULL;
 631         struct inode *newinode = NULL;
 632         __u32 oplock = 0;
 633         struct cifs_fid fid;
 634         struct cifs_open_parms oparms;
 635         FILE_ALL_INFO *buf = NULL;
 636         unsigned int bytes_written;
 637         struct win_dev *pdev;
 638         struct kvec iov[2];
 639
 640         if (!old_valid_dev(device_number))
 641                 return -EINVAL;
 642
 643         cifs_sb = CIFS_SB(inode->i_sb);
 644         tlink = cifs_sb_tlink(cifs_sb);
 645         if (IS_ERR(tlink))
 646                 return PTR_ERR(tlink);
 647
 648         tcon = tlink_tcon(tlink);
 649
 650         xid = get_xid();
 651
 652         full_path = build_path_from_dentry(direntry);
 653         if (full_path == NULL) {
 654                 rc = -ENOMEM;
 655                 goto mknod_out;
 656         }
 657
 658         if (tcon->unix_ext) {
 659                 struct cifs_unix_set_info_args args = {
 660                         .mode   = mode & ~current_umask(),
 661                         .ctime  = NO_CHANGE_64,
 662                         .atime  = NO_CHANGE_64,
 663                         .mtime  = NO_CHANGE_64,
 664                         .device = device_number,
 665                 };
 666                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
 667                         args.uid = current_fsuid();
 668                         args.gid = current_fsgid();
 669                 } else {
 670                         args.uid = INVALID_UID; /* no change */
 671                         args.gid = INVALID_GID; /* no change */
 672                 }
 673                 rc = CIFSSMBUnixSetPathInfo(xid, tcon, full_path, &args,
 674                                             cifs_sb->local_nls,
 675                                             cifs_remap(cifs_sb));
 676                 if (rc)
 677                         goto mknod_out;
 678
 679                 rc = cifs_get_inode_info_unix(&newinode, full_path,
 680                                                 inode->i_sb, xid);
 681
 682                 if (rc == 0)
 683                         d_instantiate(direntry, newinode);
 684                 goto mknod_out;
 685         }
 686
 687         if (!S_ISCHR(mode) && !S_ISBLK(mode))
 688                 goto mknod_out;
 689
 690         if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL))
 691                 goto mknod_out;
 692
 693
 694         cifs_dbg(FYI, "sfu compat create special file\n");
 695
 696         buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
 697         if (buf == NULL) {
 698                 rc = -ENOMEM;
 699                 goto mknod_out;
 700         }
 701
 702         if (backup_cred(cifs_sb))
 703                 create_options |= CREATE_OPEN_BACKUP_INTENT;
 704
 705         oparms.tcon = tcon;
 706         oparms.cifs_sb = cifs_sb;
 707         oparms.desired_access = GENERIC_WRITE;
 708         oparms.create_options = create_options;
 709         oparms.disposition = FILE_CREATE;
 710         oparms.path = full_path;
 711         oparms.fid = &fid;
 712         oparms.reconnect = false;
 713
 714         if (tcon->ses->server->oplocks)
 715                 oplock = REQ_OPLOCK;
 716         else
 717                 oplock = 0;
 718         rc = tcon->ses->server->ops->open(xid, &oparms, &oplock, buf);
 719         if (rc)
 720                 goto mknod_out;
 721
 722         /*
 723          * BB Do not bother to decode buf since no local inode yet to put
 724          * timestamps in, but we can reuse it safely.
 725          */
 726
 727         pdev = (struct win_dev *)buf;
 728         io_parms.pid = current->tgid;
 729         io_parms.tcon = tcon;
 730         io_parms.offset = 0;
 731         io_parms.length = sizeof(struct win_dev);
 732         iov[1].iov_base = buf;
 733         iov[1].iov_len = sizeof(struct win_dev);
 734         if (S_ISCHR(mode)) {
 735                 memcpy(pdev->type, "IntxCHR", 8);
 736                 pdev->major = cpu_to_le64(MAJOR(device_number));
 737                 pdev->minor = cpu_to_le64(MINOR(device_number));
 738                 rc = tcon->ses->server->ops->sync_write(xid, &fid, &io_parms,
 739                                                         &bytes_written, iov, 1);
 740         } else if (S_ISBLK(mode)) {
 741                 memcpy(pdev->type, "IntxBLK", 8);
 742                 pdev->major = cpu_to_le64(MAJOR(device_number));
 743                 pdev->minor = cpu_to_le64(MINOR(device_number));
 744                 rc = tcon->ses->server->ops->sync_write(xid, &fid, &io_parms,
 745                                                         &bytes_written, iov, 1);
 746         }
 747         tcon->ses->server->ops->close(xid, tcon, &fid);
 748         d_drop(direntry);
 749
 750         /* FIXME: add code here to set EAs */
 751
 752 mknod_out:
 753         kfree(full_path);
 754         kfree(buf);
 755         free_xid(xid);
 756         cifs_put_tlink(tlink);
 757         return rc;
 758 }
 759
 760 struct dentry *
 761 cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,
 762             unsigned int flags)
 763 {
 764         unsigned int xid;
 765         int rc = 0; /* to get around spurious gcc warning, set to zero here */
 766         struct cifs_sb_info *cifs_sb;
 767         struct tcon_link *tlink;
 768         struct cifs_tcon *pTcon;
 769         struct inode *newInode = NULL;
 770         char *full_path = NULL;
 771
 772         xid = get_xid();
 773
 774         cifs_dbg(FYI, "parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
 775                  parent_dir_inode, direntry, direntry);
 776
 777         /* check whether path exists */
 778
 779         cifs_sb = CIFS_SB(parent_dir_inode->i_sb);
 780         tlink = cifs_sb_tlink(cifs_sb);
 781         if (IS_ERR(tlink)) {
 782                 free_xid(xid);
 783                 return ERR_CAST(tlink);
 784         }
 785         pTcon = tlink_tcon(tlink);
 786
 787         rc = check_name(direntry, pTcon);
 788         if (unlikely(rc)) {
 789                 cifs_put_tlink(tlink);
 790                 free_xid(xid);
 791                 return ERR_PTR(rc);
 792         }
 793
 794         /* can not grab the rename sem here since it would
 795         deadlock in the cases (beginning of sys_rename itself)
 796         in which we already have the sb rename sem */
 797         full_path = build_path_from_dentry(direntry);
 798         if (full_path == NULL) {
 799                 cifs_put_tlink(tlink);
 800                 free_xid(xid);
 801                 return ERR_PTR(-ENOMEM);
 802         }
 803
 804         if (d_really_is_positive(direntry)) {
 805                 cifs_dbg(FYI, "non-NULL inode in lookup\n");
 806         } else {
 807                 cifs_dbg(FYI, "NULL inode in lookup\n");
 808         }
 809         cifs_dbg(FYI, "Full path: %s inode = 0x%p\n",
 810                  full_path, d_inode(direntry));
 811
 812         if (pTcon->unix_ext) {
 813                 rc = cifs_get_inode_info_unix(&newInode, full_path,
 814                                               parent_dir_inode->i_sb, xid);
 815         } else {
 816                 rc = cifs_get_inode_info(&newInode, full_path, NULL,
 817                                 parent_dir_inode->i_sb, xid, NULL);
 818         }
 819
 820         if (rc == 0) {
 821                 /* since paths are not looked up by component - the parent
 822                    directories are presumed to be good here */
 823                 renew_parental_timestamps(direntry);
 824         } else if (rc == -ENOENT) {
 825                 cifs_set_time(direntry, jiffies);
 826                 newInode = NULL;
 827         } else {
 828                 if (rc != -EACCES) {
 829                         cifs_dbg(FYI, "Unexpected lookup error %d\n", rc);
 830                         /* We special case check for Access Denied - since that
 831                         is a common return code */
 832                 }
 833                 newInode = ERR_PTR(rc);
 834         }
 835         kfree(full_path);
 836         cifs_put_tlink(tlink);
 837         free_xid(xid);
 838         return d_splice_alias(newInode, direntry);
 839 }
 840
 841 static int
 842 cifs_d_revalidate(struct dentry *direntry, unsigned int flags)
 843 {
 844         if (flags & LOOKUP_RCU)
 845                 return -ECHILD;
 846
 847         if (d_really_is_positive(direntry)) {
 848                 if (cifs_revalidate_dentry(direntry))
 849                         return 0;
 850                 else {
 851                         /*
 852                          * If the inode wasn't known to be a dfs entry when
 853                          * the dentry was instantiated, such as when created
 854                          * via ->readdir(), it needs to be set now since the
 855                          * attributes will have been updated by
 856                          * cifs_revalidate_dentry().
 857                          */
 858                         if (IS_AUTOMOUNT(d_inode(direntry)) &&
 859                            !(direntry->d_flags & DCACHE_NEED_AUTOMOUNT)) {
 860                                 spin_lock(&direntry->d_lock);
 861                                 direntry->d_flags |= DCACHE_NEED_AUTOMOUNT;
 862                                 spin_unlock(&direntry->d_lock);
 863                         }
 864
 865                         return 1;
 866                 }
 867         }
 868
 869         /*
 870          * This may be nfsd (or something), anyway, we can't see the
 871          * intent of this. So, since this can be for creation, drop it.
 872          */
 873         if (!flags)
 874                 return 0;
 875
 876         /*
 877          * Drop the negative dentry, in order to make sure to use the
 878          * case sensitive name which is specified by user if this is
 879          * for creation.
 880          */
 881         if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))
 882                 return 0;
 883
 884         if (time_after(jiffies, cifs_get_time(direntry) + HZ) || !lookupCacheEnabled)
 885                 return 0;
 886
 887         return 1;
 888 }
 889
 890 /* static int cifs_d_delete(struct dentry *direntry)
 891 {
 892         int rc = 0;
 893
 894         cifs_dbg(FYI, "In cifs d_delete, name = %pd\n", direntry);
 895
 896         return rc;
 897 }     */
 898
 899 const struct dentry_operations cifs_dentry_ops = {
 900         .d_revalidate = cifs_d_revalidate,
 901         .d_automount = cifs_dfs_d_automount,
 902 /* d_delete:       cifs_d_delete,      */ /* not needed except for debugging */
 903 };
 904
 905 static int cifs_ci_hash(const struct dentry *dentry, struct qstr *q)
 906 {
 907         struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;
 908         unsigned long hash;
 909         wchar_t c;
 910         int i, charlen;
 911
 912         hash = init_name_hash(dentry);
 913         for (i = 0; i < q->len; i += charlen) {
 914                 charlen = codepage->char2uni(&q->name[i], q->len - i, &c);
 915                 /* error out if we can't convert the character */
 916                 if (unlikely(charlen < 0))
 917                         return charlen;
 918                 hash = partial_name_hash(cifs_toupper(c), hash);
 919         }
 920         q->hash = end_name_hash(hash);
 921
 922         return 0;
 923 }
 924
 925 static int cifs_ci_compare(const struct dentry *dentry,
 926                 unsigned int len, const char *str, const struct qstr *name)
 927 {
 928         struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;
 929         wchar_t c1, c2;
 930         int i, l1, l2;
 931
 932         /*
 933          * We make the assumption here that uppercase characters in the local
 934          * codepage are always the same length as their lowercase counterparts.
 935          *
 936          * If that's ever not the case, then this will fail to match it.
 937          */
 938         if (name->len != len)
 939                 return 1;
 940
 941         for (i = 0; i < len; i += l1) {
 942                 /* Convert characters in both strings to UTF-16. */
 943                 l1 = codepage->char2uni(&str[i], len - i, &c1);
 944                 l2 = codepage->char2uni(&name->name[i], name->len - i, &c2);
 945
 946                 /*
 947                  * If we can't convert either character, just declare it to
 948                  * be 1 byte long and compare the original byte.
 949                  */
 950                 if (unlikely(l1 < 0 && l2 < 0)) {
 951                         if (str[i] != name->name[i])
 952                                 return 1;
 953                         l1 = 1;
 954                         continue;
 955                 }
 956
 957                 /*
 958                  * Here, we again ass|u|me that upper/lowercase versions of
 959                  * a character are the same length in the local NLS.
 960                  */
 961                 if (l1 != l2)
 962                         return 1;
 963
 964                 /* Now compare uppercase versions of these characters */
 965                 if (cifs_toupper(c1) != cifs_toupper(c2))
 966                         return 1;
 967         }
 968
 969         return 0;
 970 }
 971
 972 const struct dentry_operations cifs_ci_dentry_ops = {
 973         .d_revalidate = cifs_d_revalidate,
 974         .d_hash = cifs_ci_hash,
 975         .d_compare = cifs_ci_compare,
 976         .d_automount = cifs_dfs_d_automount,
 977 };