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                 memcpy(full_path, tcon->treeName, dfsplen);
  73         full_path[dfsplen] = CIFS_DIR_SEP(cifs_sb);
  74         memcpy(full_path + dfsplen + 1, vol->prepath, pplen);
  75         convert_delimiter(full_path, CIFS_DIR_SEP(cifs_sb));
  76         return full_path;
  77 }
  78
  79 /* Note: caller must free return buffer */
  80 char *
  81 build_path_from_dentry(struct dentry *direntry)
  82 {
  83         struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
  84         struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
  85         bool prefix = tcon->Flags & SMB_SHARE_IS_IN_DFS;
  86
  87         return build_path_from_dentry_optional_prefix(direntry,
  88                                                       prefix);
  89 }
  90
  91 char *
  92 build_path_from_dentry_optional_prefix(struct dentry *direntry, bool prefix)
  93 {
  94         struct dentry *temp;
  95         int namelen;
  96         int dfsplen;
  97         int pplen = 0;
  98         char *full_path;
  99         char dirsep;
 100         struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
 101         struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
 102         unsigned seq;
 103
 104         dirsep = CIFS_DIR_SEP(cifs_sb);
 105         if (prefix)
 106                 dfsplen = strnlen(tcon->treeName, MAX_TREE_SIZE + 1);
 107         else
 108                 dfsplen = 0;
 109
 110         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_USE_PREFIX_PATH)
 111                 pplen = cifs_sb->prepath ? strlen(cifs_sb->prepath) + 1 : 0;
 112
 113 cifs_bp_rename_retry:
 114         namelen = dfsplen + pplen;
 115         seq = read_seqbegin(&rename_lock);
 116         rcu_read_lock();
 117         for (temp = direntry; !IS_ROOT(temp);) {
 118                 namelen += (1 + temp->d_name.len);
 119                 temp = temp->d_parent;
 120                 if (temp == NULL) {
 121                         cifs_dbg(VFS, "corrupt dentry\n");
 122                         rcu_read_unlock();
 123                         return NULL;
 124                 }
 125         }
 126         rcu_read_unlock();
 127
 128         full_path = kmalloc(namelen+1, GFP_ATOMIC);
 129         if (full_path == NULL)
 130                 return full_path;
 131         full_path[namelen] = 0; /* trailing null */
 132         rcu_read_lock();
 133         for (temp = direntry; !IS_ROOT(temp);) {
 134                 spin_lock(&temp->d_lock);
 135                 namelen -= 1 + temp->d_name.len;
 136                 if (namelen < 0) {
 137                         spin_unlock(&temp->d_lock);
 138                         break;
 139                 } else {
 140                         full_path[namelen] = dirsep;
 141                         strncpy(full_path + namelen + 1, temp->d_name.name,
 142                                 temp->d_name.len);
 143                         cifs_dbg(FYI, "name: %s\n", full_path + namelen);
 144                 }
 145                 spin_unlock(&temp->d_lock);
 146                 temp = temp->d_parent;
 147                 if (temp == NULL) {
 148                         cifs_dbg(VFS, "corrupt dentry\n");
 149                         rcu_read_unlock();
 150                         kfree(full_path);
 151                         return NULL;
 152                 }
 153         }
 154         rcu_read_unlock();
 155         if (namelen != dfsplen + pplen || read_seqretry(&rename_lock, seq)) {
 156                 cifs_dbg(FYI, "did not end path lookup where expected. namelen=%ddfsplen=%d\n",
 157                          namelen, dfsplen);
 158                 /* presumably this is only possible if racing with a rename
 159                 of one of the parent directories  (we can not lock the dentries
 160                 above us to prevent this, but retrying should be harmless) */
 161                 kfree(full_path);
 162                 goto cifs_bp_rename_retry;
 163         }
 164         /* DIR_SEP already set for byte  0 / vs \ but not for
 165            subsequent slashes in prepath which currently must
 166            be entered the right way - not sure if there is an alternative
 167            since the '\' is a valid posix character so we can not switch
 168            those safely to '/' if any are found in the middle of the prepath */
 169         /* BB test paths to Windows with '/' in the midst of prepath */
 170
 171         if (pplen) {
 172                 int i;
 173
 174                 cifs_dbg(FYI, "using cifs_sb prepath <%s>\n", cifs_sb->prepath);
 175                 memcpy(full_path+dfsplen+1, cifs_sb->prepath, pplen-1);
 176                 full_path[dfsplen] = dirsep;
 177                 for (i = 0; i < pplen-1; i++)
 178                         if (full_path[dfsplen+1+i] == '/')
 179                                 full_path[dfsplen+1+i] = CIFS_DIR_SEP(cifs_sb);
 180         }
 181
 182         if (dfsplen) {
 183                 strncpy(full_path, tcon->treeName, dfsplen);
 184                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS) {
 185                         int i;
 186                         for (i = 0; i < dfsplen; i++) {
 187                                 if (full_path[i] == '\\')
 188                                         full_path[i] = '/';
 189                         }
 190                 }
 191         }
 192         return full_path;
 193 }
 194
 195 /*
 196  * Don't allow path components longer than the server max.
 197  * Don't allow the separator character in a path component.
 198  * The VFS will not allow "/", but "\" is allowed by posix.
 199  */
 200 static int
 201 check_name(struct dentry *direntry, struct cifs_tcon *tcon)
 202 {
 203         struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
 204         int i;
 205
 206         if (unlikely(tcon->fsAttrInfo.MaxPathNameComponentLength &&
 207                      direntry->d_name.len >
 208                      le32_to_cpu(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)
 248                 return -ENOMEM;
 249
 250         if (tcon->unix_ext && cap_unix(tcon->ses) && !tcon->broken_posix_open &&
 251             (CIFS_UNIX_POSIX_PATH_OPS_CAP &
 252                         le64_to_cpu(tcon->fsUnixInfo.Capability))) {
 253                 rc = cifs_posix_open(full_path, &newinode, inode->i_sb, mode,
 254                                      oflags, oplock, &fid->netfid, xid);
 255                 switch (rc) {
 256                 case 0:
 257                         if (newinode == NULL) {
 258                                 /* query inode info */
 259                                 goto cifs_create_get_file_info;
 260                         }
 261
 262                         if (S_ISDIR(newinode->i_mode)) {
 263                                 CIFSSMBClose(xid, tcon, fid->netfid);
 264                                 iput(newinode);
 265                                 rc = -EISDIR;
 266                                 goto out;
 267                         }
 268
 269                         if (!S_ISREG(newinode->i_mode)) {
 270                                 /*
 271                                  * The server may allow us to open things like
 272                                  * FIFOs, but the client isn't set up to deal
 273                                  * with that. If it's not a regular file, just
 274                                  * close it and proceed as if it were a normal
 275                                  * lookup.
 276                                  */
 277                                 CIFSSMBClose(xid, tcon, fid->netfid);
 278                                 goto cifs_create_get_file_info;
 279                         }
 280                         /* success, no need to query */
 281                         goto cifs_create_set_dentry;
 282
 283                 case -ENOENT:
 284                         goto cifs_create_get_file_info;
 285
 286                 case -EIO:
 287                 case -EINVAL:
 288                         /*
 289                          * EIO could indicate that (posix open) operation is not
 290                          * supported, despite what server claimed in capability
 291                          * negotiation.
 292                          *
 293                          * POSIX open in samba versions 3.3.1 and earlier could
 294                          * incorrectly fail with invalid parameter.
 295                          */
 296                         tcon->broken_posix_open = true;
 297                         break;
 298
 299                 case -EREMOTE:
 300                 case -EOPNOTSUPP:
 301                         /*
 302                          * EREMOTE indicates DFS junction, which is not handled
 303                          * in posix open.  If either that or op not supported
 304                          * returned, follow the normal lookup.
 305                          */
 306                         break;
 307
 308                 default:
 309                         goto out;
 310                 }
 311                 /*
 312                  * fallthrough to retry, using older open call, this is case
 313                  * where server does not support this SMB level, and falsely
 314                  * claims capability (also get here for DFS case which should be
 315                  * rare for path not covered on files)
 316                  */
 317         }
 318
 319         desired_access = 0;
 320         if (OPEN_FMODE(oflags) & FMODE_READ)
 321                 desired_access |= GENERIC_READ; /* is this too little? */
 322         if (OPEN_FMODE(oflags) & FMODE_WRITE)
 323                 desired_access |= GENERIC_WRITE;
 324
 325         disposition = FILE_OVERWRITE_IF;
 326         if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
 327                 disposition = FILE_CREATE;
 328         else if ((oflags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))
 329                 disposition = FILE_OVERWRITE_IF;
 330         else if ((oflags & O_CREAT) == O_CREAT)
 331                 disposition = FILE_OPEN_IF;
 332         else
 333                 cifs_dbg(FYI, "Create flag not set in create function\n");
 334
 335         /*
 336          * BB add processing to set equivalent of mode - e.g. via CreateX with
 337          * ACLs
 338          */
 339
 340         if (!server->ops->open) {
 341                 rc = -ENOSYS;
 342                 goto out;
 343         }
 344
 345         buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
 346         if (buf == NULL) {
 347                 rc = -ENOMEM;
 348                 goto out;
 349         }
 350
 351         /*
 352          * if we're not using unix extensions, see if we need to set
 353          * ATTR_READONLY on the create call
 354          */
 355         if (!tcon->unix_ext && (mode & S_IWUGO) == 0)
 356                 create_options |= CREATE_OPTION_READONLY;
 357
 358         oparms.tcon = tcon;
 359         oparms.cifs_sb = cifs_sb;
 360         oparms.desired_access = desired_access;
 361         oparms.create_options = cifs_create_options(cifs_sb, create_options);
 362         oparms.disposition = disposition;
 363         oparms.path = full_path;
 364         oparms.fid = fid;
 365         oparms.reconnect = false;
 366         oparms.mode = mode;
 367         rc = server->ops->open(xid, &oparms, oplock, buf);
 368         if (rc) {
 369                 cifs_dbg(FYI, "cifs_create returned 0x%x\n", rc);
 370                 goto out;
 371         }
 372
 373         /*
 374          * If Open reported that we actually created a file then we now have to
 375          * set the mode if possible.
 376          */
 377         if ((tcon->unix_ext) && (*oplock & CIFS_CREATE_ACTION)) {
 378                 struct cifs_unix_set_info_args args = {
 379                                 .mode   = mode,
 380                                 .ctime  = NO_CHANGE_64,
 381                                 .atime  = NO_CHANGE_64,
 382                                 .mtime  = NO_CHANGE_64,
 383                                 .device = 0,
 384                 };
 385
 386                 if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
 387                         args.uid = current_fsuid();
 388                         if (inode->i_mode & S_ISGID)
 389                                 args.gid = inode->i_gid;
 390                         else
 391                                 args.gid = current_fsgid();
 392                 } else {
 393                         args.uid = INVALID_UID; /* no change */
 394                         args.gid = INVALID_GID; /* no change */
 395                 }
 396                 CIFSSMBUnixSetFileInfo(xid, tcon, &args, fid->netfid,
 397                                        current->tgid);
 398         } else {
 399                 /*
 400                  * BB implement mode setting via Windows security
 401                  * descriptors e.g.
 402                  */
 403                 /* CIFSSMBWinSetPerms(xid,tcon,path,mode,-1,-1,nls);*/
 404
 405                 /* Could set r/o dos attribute if mode & 0222 == 0 */
 406         }
 407
 408 cifs_create_get_file_info:
 409         /* server might mask mode so we have to query for it */
 410         if (tcon->unix_ext)
 411                 rc = cifs_get_inode_info_unix(&newinode, full_path, inode->i_sb,
 412                                               xid);
 413         else {
 414                 rc = cifs_get_inode_info(&newinode, full_path, buf, inode->i_sb,
 415                                          xid, fid);
 416                 if (newinode) {
 417                         if (server->ops->set_lease_key)
 418                                 server->ops->set_lease_key(newinode, fid);
 419                         if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DYNPERM)
 420                                 newinode->i_mode = mode;
 421                         if ((*oplock & CIFS_CREATE_ACTION) &&
 422                             (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID)) {
 423                                 newinode->i_uid = current_fsuid();
 424                                 if (inode->i_mode & S_ISGID)
 425                                         newinode->i_gid = inode->i_gid;
 426                                 else
 427                                         newinode->i_gid = current_fsgid();
 428                         }
 429                 }
 430         }
 431
 432 cifs_create_set_dentry:
 433         if (rc != 0) {
 434                 cifs_dbg(FYI, "Create worked, get_inode_info failed rc = %d\n",
 435                          rc);
 436                 goto out_err;
 437         }
 438
 439         if (S_ISDIR(newinode->i_mode)) {
 440                 rc = -EISDIR;
 441                 goto out_err;
 442         }
 443
 444         d_drop(direntry);
 445         d_add(direntry, newinode);
 446
 447 out:
 448         kfree(buf);
 449         kfree(full_path);
 450         return rc;
 451
 452 out_err:
 453         if (server->ops->close)
 454                 server->ops->close(xid, tcon, fid);
 455         if (newinode)
 456                 iput(newinode);
 457         goto out;
 458 }
 459
 460 int
 461 cifs_atomic_open(struct inode *inode, struct dentry *direntry,
 462                  struct file *file, unsigned oflags, umode_t mode)
 463 {
 464         int rc;
 465         unsigned int xid;
 466         struct tcon_link *tlink;
 467         struct cifs_tcon *tcon;
 468         struct TCP_Server_Info *server;
 469         struct cifs_fid fid;
 470         struct cifs_pending_open open;
 471         __u32 oplock;
 472         struct cifsFileInfo *file_info;
 473
 474         /*
 475          * Posix open is only called (at lookup time) for file create now. For
 476          * opens (rather than creates), because we do not know if it is a file
 477          * or directory yet, and current Samba no longer allows us to do posix
 478          * open on dirs, we could end up wasting an open call on what turns out
 479          * to be a dir. For file opens, we wait to call posix open till
 480          * cifs_open.  It could be added to atomic_open in the future but the
 481          * performance tradeoff of the extra network request when EISDIR or
 482          * EACCES is returned would have to be weighed against the 50% reduction
 483          * in network traffic in the other paths.
 484          */
 485         if (!(oflags & O_CREAT)) {
 486                 struct dentry *res;
 487
 488                 /*
 489                  * Check for hashed negative dentry. We have already revalidated
 490                  * the dentry and it is fine. No need to perform another lookup.
 491                  */
 492                 if (!d_in_lookup(direntry))
 493                         return -ENOENT;
 494
 495                 res = cifs_lookup(inode, direntry, 0);
 496                 if (IS_ERR(res))
 497                         return PTR_ERR(res);
 498
 499                 return finish_no_open(file, res);
 500         }
 501
 502         xid = get_xid();
 503
 504         cifs_dbg(FYI, "parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
 505                  inode, direntry, direntry);
 506
 507         tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));
 508         if (IS_ERR(tlink)) {
 509                 rc = PTR_ERR(tlink);
 510                 goto out_free_xid;
 511         }
 512
 513         tcon = tlink_tcon(tlink);
 514
 515         rc = check_name(direntry, tcon);
 516         if (rc)
 517                 goto out;
 518
 519         server = tcon->ses->server;
 520
 521         if (server->ops->new_lease_key)
 522                 server->ops->new_lease_key(&fid);
 523
 524         cifs_add_pending_open(&fid, tlink, &open);
 525
 526         rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode,
 527                             &oplock, &fid);
 528
 529         if (rc) {
 530                 cifs_del_pending_open(&open);
 531                 goto out;
 532         }
 533
 534         if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
 535                 file->f_mode |= FMODE_CREATED;
 536
 537         rc = finish_open(file, direntry, generic_file_open);
 538         if (rc) {
 539                 if (server->ops->close)
 540                         server->ops->close(xid, tcon, &fid);
 541                 cifs_del_pending_open(&open);
 542                 goto out;
 543         }
 544
 545         if (file->f_flags & O_DIRECT &&
 546             CIFS_SB(inode->i_sb)->mnt_cifs_flags & CIFS_MOUNT_STRICT_IO) {
 547                 if (CIFS_SB(inode->i_sb)->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
 548                         file->f_op = &cifs_file_direct_nobrl_ops;
 549                 else
 550                         file->f_op = &cifs_file_direct_ops;
 551                 }
 552
 553         file_info = cifs_new_fileinfo(&fid, file, tlink, oplock);
 554         if (file_info == NULL) {
 555                 if (server->ops->close)
 556                         server->ops->close(xid, tcon, &fid);
 557                 cifs_del_pending_open(&open);
 558                 rc = -ENOMEM;
 559         }
 560
 561 out:
 562         cifs_put_tlink(tlink);
 563 out_free_xid:
 564         free_xid(xid);
 565         return rc;
 566 }
 567
 568 int cifs_create(struct inode *inode, struct dentry *direntry, umode_t mode,
 569                 bool excl)
 570 {
 571         int rc;
 572         unsigned int xid = get_xid();
 573         /*
 574          * BB below access is probably too much for mknod to request
 575          *    but we have to do query and setpathinfo so requesting
 576          *    less could fail (unless we want to request getatr and setatr
 577          *    permissions (only).  At least for POSIX we do not have to
 578          *    request so much.
 579          */
 580         unsigned oflags = O_EXCL | O_CREAT | O_RDWR;
 581         struct tcon_link *tlink;
 582         struct cifs_tcon *tcon;
 583         struct TCP_Server_Info *server;
 584         struct cifs_fid fid;
 585         __u32 oplock;
 586
 587         cifs_dbg(FYI, "cifs_create parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
 588                  inode, direntry, direntry);
 589
 590         tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));
 591         rc = PTR_ERR(tlink);
 592         if (IS_ERR(tlink))
 593                 goto out_free_xid;
 594
 595         tcon = tlink_tcon(tlink);
 596         server = tcon->ses->server;
 597
 598         if (server->ops->new_lease_key)
 599                 server->ops->new_lease_key(&fid);
 600
 601         rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode,
 602                             &oplock, &fid);
 603         if (!rc && server->ops->close)
 604                 server->ops->close(xid, tcon, &fid);
 605
 606         cifs_put_tlink(tlink);
 607 out_free_xid:
 608         free_xid(xid);
 609         return rc;
 610 }
 611
 612 int cifs_mknod(struct inode *inode, struct dentry *direntry, umode_t mode,
 613                 dev_t device_number)
 614 {
 615         int rc = -EPERM;
 616         unsigned int xid;
 617         struct cifs_sb_info *cifs_sb;
 618         struct tcon_link *tlink;
 619         struct cifs_tcon *tcon;
 620         char *full_path = NULL;
 621
 622         if (!old_valid_dev(device_number))
 623                 return -EINVAL;
 624
 625         cifs_sb = CIFS_SB(inode->i_sb);
 626         tlink = cifs_sb_tlink(cifs_sb);
 627         if (IS_ERR(tlink))
 628                 return PTR_ERR(tlink);
 629
 630         tcon = tlink_tcon(tlink);
 631
 632         xid = get_xid();
 633
 634         full_path = build_path_from_dentry(direntry);
 635         if (full_path == NULL) {
 636                 rc = -ENOMEM;
 637                 goto mknod_out;
 638         }
 639
 640         rc = tcon->ses->server->ops->make_node(xid, inode, direntry, tcon,
 641                                                full_path, mode,
 642                                                device_number);
 643
 644 mknod_out:
 645         kfree(full_path);
 646         free_xid(xid);
 647         cifs_put_tlink(tlink);
 648         return rc;
 649 }
 650
 651 struct dentry *
 652 cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,
 653             unsigned int flags)
 654 {
 655         unsigned int xid;
 656         int rc = 0; /* to get around spurious gcc warning, set to zero here */
 657         struct cifs_sb_info *cifs_sb;
 658         struct tcon_link *tlink;
 659         struct cifs_tcon *pTcon;
 660         struct inode *newInode = NULL;
 661         char *full_path = NULL;
 662
 663         xid = get_xid();
 664
 665         cifs_dbg(FYI, "parent inode = 0x%p name is: %pd and dentry = 0x%p\n",
 666                  parent_dir_inode, direntry, direntry);
 667
 668         /* check whether path exists */
 669
 670         cifs_sb = CIFS_SB(parent_dir_inode->i_sb);
 671         tlink = cifs_sb_tlink(cifs_sb);
 672         if (IS_ERR(tlink)) {
 673                 free_xid(xid);
 674                 return ERR_CAST(tlink);
 675         }
 676         pTcon = tlink_tcon(tlink);
 677
 678         rc = check_name(direntry, pTcon);
 679         if (unlikely(rc)) {
 680                 cifs_put_tlink(tlink);
 681                 free_xid(xid);
 682                 return ERR_PTR(rc);
 683         }
 684
 685         /* can not grab the rename sem here since it would
 686         deadlock in the cases (beginning of sys_rename itself)
 687         in which we already have the sb rename sem */
 688         full_path = build_path_from_dentry(direntry);
 689         if (full_path == NULL) {
 690                 cifs_put_tlink(tlink);
 691                 free_xid(xid);
 692                 return ERR_PTR(-ENOMEM);
 693         }
 694
 695         if (d_really_is_positive(direntry)) {
 696                 cifs_dbg(FYI, "non-NULL inode in lookup\n");
 697         } else {
 698                 cifs_dbg(FYI, "NULL inode in lookup\n");
 699         }
 700         cifs_dbg(FYI, "Full path: %s inode = 0x%p\n",
 701                  full_path, d_inode(direntry));
 702
 703         if (pTcon->unix_ext) {
 704                 rc = cifs_get_inode_info_unix(&newInode, full_path,
 705                                               parent_dir_inode->i_sb, xid);
 706         } else {
 707                 rc = cifs_get_inode_info(&newInode, full_path, NULL,
 708                                 parent_dir_inode->i_sb, xid, NULL);
 709         }
 710
 711         if (rc == 0) {
 712                 /* since paths are not looked up by component - the parent
 713                    directories are presumed to be good here */
 714                 renew_parental_timestamps(direntry);
 715         } else if (rc == -ENOENT) {
 716                 cifs_set_time(direntry, jiffies);
 717                 newInode = NULL;
 718         } else {
 719                 if (rc != -EACCES) {
 720                         cifs_dbg(FYI, "Unexpected lookup error %d\n", rc);
 721                         /* We special case check for Access Denied - since that
 722                         is a common return code */
 723                 }
 724                 newInode = ERR_PTR(rc);
 725         }
 726         kfree(full_path);
 727         cifs_put_tlink(tlink);
 728         free_xid(xid);
 729         return d_splice_alias(newInode, direntry);
 730 }
 731
 732 static int
 733 cifs_d_revalidate(struct dentry *direntry, unsigned int flags)
 734 {
 735         struct inode *inode;
 736
 737         if (flags & LOOKUP_RCU)
 738                 return -ECHILD;
 739
 740         if (d_really_is_positive(direntry)) {
 741                 inode = d_inode(direntry);
 742                 if ((flags & LOOKUP_REVAL) && !CIFS_CACHE_READ(CIFS_I(inode)))
 743                         CIFS_I(inode)->time = 0; /* force reval */
 744
 745                 if (cifs_revalidate_dentry(direntry))
 746                         return 0;
 747                 else {
 748                         /*
 749                          * If the inode wasn't known to be a dfs entry when
 750                          * the dentry was instantiated, such as when created
 751                          * via ->readdir(), it needs to be set now since the
 752                          * attributes will have been updated by
 753                          * cifs_revalidate_dentry().
 754                          */
 755                         if (IS_AUTOMOUNT(inode) &&
 756                            !(direntry->d_flags & DCACHE_NEED_AUTOMOUNT)) {
 757                                 spin_lock(&direntry->d_lock);
 758                                 direntry->d_flags |= DCACHE_NEED_AUTOMOUNT;
 759                                 spin_unlock(&direntry->d_lock);
 760                         }
 761
 762                         return 1;
 763                 }
 764         }
 765
 766         /*
 767          * This may be nfsd (or something), anyway, we can't see the
 768          * intent of this. So, since this can be for creation, drop it.
 769          */
 770         if (!flags)
 771                 return 0;
 772
 773         /*
 774          * Drop the negative dentry, in order to make sure to use the
 775          * case sensitive name which is specified by user if this is
 776          * for creation.
 777          */
 778         if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))
 779                 return 0;
 780
 781         if (time_after(jiffies, cifs_get_time(direntry) + HZ) || !lookupCacheEnabled)
 782                 return 0;
 783
 784         return 1;
 785 }
 786
 787 /* static int cifs_d_delete(struct dentry *direntry)
 788 {
 789         int rc = 0;
 790
 791         cifs_dbg(FYI, "In cifs d_delete, name = %pd\n", direntry);
 792
 793         return rc;
 794 }     */
 795
 796 const struct dentry_operations cifs_dentry_ops = {
 797         .d_revalidate = cifs_d_revalidate,
 798         .d_automount = cifs_dfs_d_automount,
 799 /* d_delete:       cifs_d_delete,      */ /* not needed except for debugging */
 800 };
 801
 802 static int cifs_ci_hash(const struct dentry *dentry, struct qstr *q)
 803 {
 804         struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;
 805         unsigned long hash;
 806         wchar_t c;
 807         int i, charlen;
 808
 809         hash = init_name_hash(dentry);
 810         for (i = 0; i < q->len; i += charlen) {
 811                 charlen = codepage->char2uni(&q->name[i], q->len - i, &c);
 812                 /* error out if we can't convert the character */
 813                 if (unlikely(charlen < 0))
 814                         return charlen;
 815                 hash = partial_name_hash(cifs_toupper(c), hash);
 816         }
 817         q->hash = end_name_hash(hash);
 818
 819         return 0;
 820 }
 821
 822 static int cifs_ci_compare(const struct dentry *dentry,
 823                 unsigned int len, const char *str, const struct qstr *name)
 824 {
 825         struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;
 826         wchar_t c1, c2;
 827         int i, l1, l2;
 828
 829         /*
 830          * We make the assumption here that uppercase characters in the local
 831          * codepage are always the same length as their lowercase counterparts.
 832          *
 833          * If that's ever not the case, then this will fail to match it.
 834          */
 835         if (name->len != len)
 836                 return 1;
 837
 838         for (i = 0; i < len; i += l1) {
 839                 /* Convert characters in both strings to UTF-16. */
 840                 l1 = codepage->char2uni(&str[i], len - i, &c1);
 841                 l2 = codepage->char2uni(&name->name[i], name->len - i, &c2);
 842
 843                 /*
 844                  * If we can't convert either character, just declare it to
 845                  * be 1 byte long and compare the original byte.
 846                  */
 847                 if (unlikely(l1 < 0 && l2 < 0)) {
 848                         if (str[i] != name->name[i])
 849                                 return 1;
 850                         l1 = 1;
 851                         continue;
 852                 }
 853
 854                 /*
 855                  * Here, we again ass|u|me that upper/lowercase versions of
 856                  * a character are the same length in the local NLS.
 857                  */
 858                 if (l1 != l2)
 859                         return 1;
 860
 861                 /* Now compare uppercase versions of these characters */
 862                 if (cifs_toupper(c1) != cifs_toupper(c2))
 863                         return 1;
 864         }
 865
 866         return 0;
 867 }
 868
 869 const struct dentry_operations cifs_ci_dentry_ops = {
 870         .d_revalidate = cifs_d_revalidate,
 871         .d_hash = cifs_ci_hash,
 872         .d_compare = cifs_ci_compare,
 873         .d_automount = cifs_dfs_d_automount,
 874 };