linux/fs/cifs/dir.c
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   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
  37static void
  38renew_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                direntry->d_time = jiffies;
  44                direntry = direntry->d_parent;
  45        } while (!IS_ROOT(direntry));
  46}
  47
  48char *
  49cifs_build_path_to_root(struct smb_vol *vol, struct cifs_sb_info *cifs_sb,
  50                        struct cifs_tcon *tcon)
  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 (tcon->Flags & SMB_SHARE_IS_IN_DFS)
  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 */
  81char *
  82build_path_from_dentry(struct dentry *direntry)
  83{
  84        struct dentry *temp;
  85        int namelen;
  86        int dfsplen;
  87        char *full_path;
  88        char dirsep;
  89        struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
  90        struct cifs_tcon *tcon = cifs_sb_master_tcon(cifs_sb);
  91        unsigned seq;
  92
  93        dirsep = CIFS_DIR_SEP(cifs_sb);
  94        if (tcon->Flags & SMB_SHARE_IS_IN_DFS)
  95                dfsplen = strnlen(tcon->treeName, MAX_TREE_SIZE + 1);
  96        else
  97                dfsplen = 0;
  98cifs_bp_rename_retry:
  99        namelen = dfsplen;
 100        seq = read_seqbegin(&rename_lock);
 101        rcu_read_lock();
 102        for (temp = direntry; !IS_ROOT(temp);) {
 103                namelen += (1 + temp->d_name.len);
 104                temp = temp->d_parent;
 105                if (temp == NULL) {
 106                        cifs_dbg(VFS, "corrupt dentry\n");
 107                        rcu_read_unlock();
 108                        return NULL;
 109                }
 110        }
 111        rcu_read_unlock();
 112
 113        full_path = kmalloc(namelen+1, GFP_KERNEL);
 114        if (full_path == NULL)
 115                return full_path;
 116        full_path[namelen] = 0; /* trailing null */
 117        rcu_read_lock();
 118        for (temp = direntry; !IS_ROOT(temp);) {
 119                spin_lock(&temp->d_lock);
 120                namelen -= 1 + temp->d_name.len;
 121                if (namelen < 0) {
 122                        spin_unlock(&temp->d_lock);
 123                        break;
 124                } else {
 125                        full_path[namelen] = dirsep;
 126                        strncpy(full_path + namelen + 1, temp->d_name.name,
 127                                temp->d_name.len);
 128                        cifs_dbg(FYI, "name: %s\n", full_path + namelen);
 129                }
 130                spin_unlock(&temp->d_lock);
 131                temp = temp->d_parent;
 132                if (temp == NULL) {
 133                        cifs_dbg(VFS, "corrupt dentry\n");
 134                        rcu_read_unlock();
 135                        kfree(full_path);
 136                        return NULL;
 137                }
 138        }
 139        rcu_read_unlock();
 140        if (namelen != dfsplen || read_seqretry(&rename_lock, seq)) {
 141                cifs_dbg(FYI, "did not end path lookup where expected. namelen=%ddfsplen=%d\n",
 142                         namelen, dfsplen);
 143                /* presumably this is only possible if racing with a rename
 144                of one of the parent directories  (we can not lock the dentries
 145                above us to prevent this, but retrying should be harmless) */
 146                kfree(full_path);
 147                goto cifs_bp_rename_retry;
 148        }
 149        /* DIR_SEP already set for byte  0 / vs \ but not for
 150           subsequent slashes in prepath which currently must
 151           be entered the right way - not sure if there is an alternative
 152           since the '\' is a valid posix character so we can not switch
 153           those safely to '/' if any are found in the middle of the prepath */
 154        /* BB test paths to Windows with '/' in the midst of prepath */
 155
 156        if (dfsplen) {
 157                strncpy(full_path, tcon->treeName, dfsplen);
 158                if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS) {
 159                        int i;
 160                        for (i = 0; i < dfsplen; i++) {
 161                                if (full_path[i] == '\\')
 162                                        full_path[i] = '/';
 163                        }
 164                }
 165        }
 166        return full_path;
 167}
 168
 169/*
 170 * Don't allow the separator character in a path component.
 171 * The VFS will not allow "/", but "\" is allowed by posix.
 172 */
 173static int
 174check_name(struct dentry *direntry)
 175{
 176        struct cifs_sb_info *cifs_sb = CIFS_SB(direntry->d_sb);
 177        int i;
 178
 179        if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_POSIX_PATHS)) {
 180                for (i = 0; i < direntry->d_name.len; i++) {
 181                        if (direntry->d_name.name[i] == '\\') {
 182                                cifs_dbg(FYI, "Invalid file name\n");
 183                                return -EINVAL;
 184                        }
 185                }
 186        }
 187        return 0;
 188}
 189
 190
 191/* Inode operations in similar order to how they appear in Linux file fs.h */
 192
 193static int
 194cifs_do_create(struct inode *inode, struct dentry *direntry, unsigned int xid,
 195               struct tcon_link *tlink, unsigned oflags, umode_t mode,
 196               __u32 *oplock, struct cifs_fid *fid)
 197{
 198        int rc = -ENOENT;
 199        int create_options = CREATE_NOT_DIR;
 200        int desired_access;
 201        struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
 202        struct cifs_tcon *tcon = tlink_tcon(tlink);
 203        char *full_path = NULL;
 204        FILE_ALL_INFO *buf = NULL;
 205        struct inode *newinode = NULL;
 206        int disposition;
 207        struct TCP_Server_Info *server = tcon->ses->server;
 208        struct cifs_open_parms oparms;
 209
 210        *oplock = 0;
 211        if (tcon->ses->server->oplocks)
 212                *oplock = REQ_OPLOCK;
 213
 214        full_path = build_path_from_dentry(direntry);
 215        if (full_path == NULL) {
 216                rc = -ENOMEM;
 217                goto out;
 218        }
 219
 220        if (tcon->unix_ext && cap_unix(tcon->ses) && !tcon->broken_posix_open &&
 221            (CIFS_UNIX_POSIX_PATH_OPS_CAP &
 222                        le64_to_cpu(tcon->fsUnixInfo.Capability))) {
 223                rc = cifs_posix_open(full_path, &newinode, inode->i_sb, mode,
 224                                     oflags, oplock, &fid->netfid, xid);
 225                switch (rc) {
 226                case 0:
 227                        if (newinode == NULL) {
 228                                /* query inode info */
 229                                goto cifs_create_get_file_info;
 230                        }
 231
 232                        if (!S_ISREG(newinode->i_mode)) {
 233                                /*
 234                                 * The server may allow us to open things like
 235                                 * FIFOs, but the client isn't set up to deal
 236                                 * with that. If it's not a regular file, just
 237                                 * close it and proceed as if it were a normal
 238                                 * lookup.
 239                                 */
 240                                CIFSSMBClose(xid, tcon, fid->netfid);
 241                                goto cifs_create_get_file_info;
 242                        }
 243                        /* success, no need to query */
 244                        goto cifs_create_set_dentry;
 245
 246                case -ENOENT:
 247                        goto cifs_create_get_file_info;
 248
 249                case -EIO:
 250                case -EINVAL:
 251                        /*
 252                         * EIO could indicate that (posix open) operation is not
 253                         * supported, despite what server claimed in capability
 254                         * negotiation.
 255                         *
 256                         * POSIX open in samba versions 3.3.1 and earlier could
 257                         * incorrectly fail with invalid parameter.
 258                         */
 259                        tcon->broken_posix_open = true;
 260                        break;
 261
 262                case -EREMOTE:
 263                case -EOPNOTSUPP:
 264                        /*
 265                         * EREMOTE indicates DFS junction, which is not handled
 266                         * in posix open.  If either that or op not supported
 267                         * returned, follow the normal lookup.
 268                         */
 269                        break;
 270
 271                default:
 272                        goto out;
 273                }
 274                /*
 275                 * fallthrough to retry, using older open call, this is case
 276                 * where server does not support this SMB level, and falsely
 277                 * claims capability (also get here for DFS case which should be
 278                 * rare for path not covered on files)
 279                 */
 280        }
 281
 282        desired_access = 0;
 283        if (OPEN_FMODE(oflags) & FMODE_READ)
 284                desired_access |= GENERIC_READ; /* is this too little? */
 285        if (OPEN_FMODE(oflags) & FMODE_WRITE)
 286                desired_access |= GENERIC_WRITE;
 287
 288        disposition = FILE_OVERWRITE_IF;
 289        if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
 290                disposition = FILE_CREATE;
 291        else if ((oflags & (O_CREAT | O_TRUNC)) == (O_CREAT | O_TRUNC))
 292                disposition = FILE_OVERWRITE_IF;
 293        else if ((oflags & O_CREAT) == O_CREAT)
 294                disposition = FILE_OPEN_IF;
 295        else
 296                cifs_dbg(FYI, "Create flag not set in create function\n");
 297
 298        /*
 299         * BB add processing to set equivalent of mode - e.g. via CreateX with
 300         * ACLs
 301         */
 302
 303        if (!server->ops->open) {
 304                rc = -ENOSYS;
 305                goto out;
 306        }
 307
 308        buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
 309        if (buf == NULL) {
 310                rc = -ENOMEM;
 311                goto out;
 312        }
 313
 314        /*
 315         * if we're not using unix extensions, see if we need to set
 316         * ATTR_READONLY on the create call
 317         */
 318        if (!tcon->unix_ext && (mode & S_IWUGO) == 0)
 319                create_options |= CREATE_OPTION_READONLY;
 320
 321        if (backup_cred(cifs_sb))
 322                create_options |= CREATE_OPEN_BACKUP_INTENT;
 323
 324        oparms.tcon = tcon;
 325        oparms.cifs_sb = cifs_sb;
 326        oparms.desired_access = desired_access;
 327        oparms.create_options = create_options;
 328        oparms.disposition = disposition;
 329        oparms.path = full_path;
 330        oparms.fid = fid;
 331        oparms.reconnect = false;
 332
 333        rc = server->ops->open(xid, &oparms, oplock, buf);
 334        if (rc) {
 335                cifs_dbg(FYI, "cifs_create returned 0x%x\n", rc);
 336                goto out;
 337        }
 338
 339        /*
 340         * If Open reported that we actually created a file then we now have to
 341         * set the mode if possible.
 342         */
 343        if ((tcon->unix_ext) && (*oplock & CIFS_CREATE_ACTION)) {
 344                struct cifs_unix_set_info_args args = {
 345                                .mode   = mode,
 346                                .ctime  = NO_CHANGE_64,
 347                                .atime  = NO_CHANGE_64,
 348                                .mtime  = NO_CHANGE_64,
 349                                .device = 0,
 350                };
 351
 352                if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
 353                        args.uid = current_fsuid();
 354                        if (inode->i_mode & S_ISGID)
 355                                args.gid = inode->i_gid;
 356                        else
 357                                args.gid = current_fsgid();
 358                } else {
 359                        args.uid = INVALID_UID; /* no change */
 360                        args.gid = INVALID_GID; /* no change */
 361                }
 362                CIFSSMBUnixSetFileInfo(xid, tcon, &args, fid->netfid,
 363                                       current->tgid);
 364        } else {
 365                /*
 366                 * BB implement mode setting via Windows security
 367                 * descriptors e.g.
 368                 */
 369                /* CIFSSMBWinSetPerms(xid,tcon,path,mode,-1,-1,nls);*/
 370
 371                /* Could set r/o dos attribute if mode & 0222 == 0 */
 372        }
 373
 374cifs_create_get_file_info:
 375        /* server might mask mode so we have to query for it */
 376        if (tcon->unix_ext)
 377                rc = cifs_get_inode_info_unix(&newinode, full_path, inode->i_sb,
 378                                              xid);
 379        else {
 380                rc = cifs_get_inode_info(&newinode, full_path, buf, inode->i_sb,
 381                                         xid, &fid->netfid);
 382                if (newinode) {
 383                        if (server->ops->set_lease_key)
 384                                server->ops->set_lease_key(newinode, fid);
 385                        if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DYNPERM)
 386                                newinode->i_mode = mode;
 387                        if ((*oplock & CIFS_CREATE_ACTION) &&
 388                            (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID)) {
 389                                newinode->i_uid = current_fsuid();
 390                                if (inode->i_mode & S_ISGID)
 391                                        newinode->i_gid = inode->i_gid;
 392                                else
 393                                        newinode->i_gid = current_fsgid();
 394                        }
 395                }
 396        }
 397
 398cifs_create_set_dentry:
 399        if (rc != 0) {
 400                cifs_dbg(FYI, "Create worked, get_inode_info failed rc = %d\n",
 401                         rc);
 402                if (server->ops->close)
 403                        server->ops->close(xid, tcon, fid);
 404                goto out;
 405        }
 406        d_drop(direntry);
 407        d_add(direntry, newinode);
 408
 409out:
 410        kfree(buf);
 411        kfree(full_path);
 412        return rc;
 413}
 414
 415int
 416cifs_atomic_open(struct inode *inode, struct dentry *direntry,
 417                 struct file *file, unsigned oflags, umode_t mode,
 418                 int *opened)
 419{
 420        int rc;
 421        unsigned int xid;
 422        struct tcon_link *tlink;
 423        struct cifs_tcon *tcon;
 424        struct TCP_Server_Info *server;
 425        struct cifs_fid fid;
 426        struct cifs_pending_open open;
 427        __u32 oplock;
 428        struct cifsFileInfo *file_info;
 429
 430        /*
 431         * Posix open is only called (at lookup time) for file create now. For
 432         * opens (rather than creates), because we do not know if it is a file
 433         * or directory yet, and current Samba no longer allows us to do posix
 434         * open on dirs, we could end up wasting an open call on what turns out
 435         * to be a dir. For file opens, we wait to call posix open till
 436         * cifs_open.  It could be added to atomic_open in the future but the
 437         * performance tradeoff of the extra network request when EISDIR or
 438         * EACCES is returned would have to be weighed against the 50% reduction
 439         * in network traffic in the other paths.
 440         */
 441        if (!(oflags & O_CREAT)) {
 442                struct dentry *res;
 443
 444                /*
 445                 * Check for hashed negative dentry. We have already revalidated
 446                 * the dentry and it is fine. No need to perform another lookup.
 447                 */
 448                if (!d_unhashed(direntry))
 449                        return -ENOENT;
 450
 451                res = cifs_lookup(inode, direntry, 0);
 452                if (IS_ERR(res))
 453                        return PTR_ERR(res);
 454
 455                return finish_no_open(file, res);
 456        }
 457
 458        rc = check_name(direntry);
 459        if (rc)
 460                return rc;
 461
 462        xid = get_xid();
 463
 464        cifs_dbg(FYI, "parent inode = 0x%p name is: %s and dentry = 0x%p\n",
 465                 inode, direntry->d_name.name, direntry);
 466
 467        tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));
 468        if (IS_ERR(tlink)) {
 469                rc = PTR_ERR(tlink);
 470                goto out_free_xid;
 471        }
 472
 473        tcon = tlink_tcon(tlink);
 474        server = tcon->ses->server;
 475
 476        if (server->ops->new_lease_key)
 477                server->ops->new_lease_key(&fid);
 478
 479        cifs_add_pending_open(&fid, tlink, &open);
 480
 481        rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode,
 482                            &oplock, &fid);
 483
 484        if (rc) {
 485                cifs_del_pending_open(&open);
 486                goto out;
 487        }
 488
 489        if ((oflags & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
 490                *opened |= FILE_CREATED;
 491
 492        rc = finish_open(file, direntry, generic_file_open, opened);
 493        if (rc) {
 494                if (server->ops->close)
 495                        server->ops->close(xid, tcon, &fid);
 496                cifs_del_pending_open(&open);
 497                goto out;
 498        }
 499
 500        file_info = cifs_new_fileinfo(&fid, file, tlink, oplock);
 501        if (file_info == NULL) {
 502                if (server->ops->close)
 503                        server->ops->close(xid, tcon, &fid);
 504                cifs_del_pending_open(&open);
 505                fput(file);
 506                rc = -ENOMEM;
 507        }
 508
 509out:
 510        cifs_put_tlink(tlink);
 511out_free_xid:
 512        free_xid(xid);
 513        return rc;
 514}
 515
 516int cifs_create(struct inode *inode, struct dentry *direntry, umode_t mode,
 517                bool excl)
 518{
 519        int rc;
 520        unsigned int xid = get_xid();
 521        /*
 522         * BB below access is probably too much for mknod to request
 523         *    but we have to do query and setpathinfo so requesting
 524         *    less could fail (unless we want to request getatr and setatr
 525         *    permissions (only).  At least for POSIX we do not have to
 526         *    request so much.
 527         */
 528        unsigned oflags = O_EXCL | O_CREAT | O_RDWR;
 529        struct tcon_link *tlink;
 530        struct cifs_tcon *tcon;
 531        struct TCP_Server_Info *server;
 532        struct cifs_fid fid;
 533        __u32 oplock;
 534
 535        cifs_dbg(FYI, "cifs_create parent inode = 0x%p name is: %s and dentry = 0x%p\n",
 536                 inode, direntry->d_name.name, direntry);
 537
 538        tlink = cifs_sb_tlink(CIFS_SB(inode->i_sb));
 539        rc = PTR_ERR(tlink);
 540        if (IS_ERR(tlink))
 541                goto out_free_xid;
 542
 543        tcon = tlink_tcon(tlink);
 544        server = tcon->ses->server;
 545
 546        if (server->ops->new_lease_key)
 547                server->ops->new_lease_key(&fid);
 548
 549        rc = cifs_do_create(inode, direntry, xid, tlink, oflags, mode,
 550                            &oplock, &fid);
 551        if (!rc && server->ops->close)
 552                server->ops->close(xid, tcon, &fid);
 553
 554        cifs_put_tlink(tlink);
 555out_free_xid:
 556        free_xid(xid);
 557        return rc;
 558}
 559
 560int cifs_mknod(struct inode *inode, struct dentry *direntry, umode_t mode,
 561                dev_t device_number)
 562{
 563        int rc = -EPERM;
 564        unsigned int xid;
 565        int create_options = CREATE_NOT_DIR | CREATE_OPTION_SPECIAL;
 566        struct cifs_sb_info *cifs_sb;
 567        struct tcon_link *tlink;
 568        struct cifs_tcon *pTcon;
 569        struct cifs_io_parms io_parms;
 570        char *full_path = NULL;
 571        struct inode *newinode = NULL;
 572        int oplock = 0;
 573        u16 fileHandle;
 574        FILE_ALL_INFO *buf = NULL;
 575        unsigned int bytes_written;
 576        struct win_dev *pdev;
 577
 578        if (!old_valid_dev(device_number))
 579                return -EINVAL;
 580
 581        cifs_sb = CIFS_SB(inode->i_sb);
 582        tlink = cifs_sb_tlink(cifs_sb);
 583        if (IS_ERR(tlink))
 584                return PTR_ERR(tlink);
 585
 586        pTcon = tlink_tcon(tlink);
 587
 588        xid = get_xid();
 589
 590        full_path = build_path_from_dentry(direntry);
 591        if (full_path == NULL) {
 592                rc = -ENOMEM;
 593                goto mknod_out;
 594        }
 595
 596        if (pTcon->unix_ext) {
 597                struct cifs_unix_set_info_args args = {
 598                        .mode   = mode & ~current_umask(),
 599                        .ctime  = NO_CHANGE_64,
 600                        .atime  = NO_CHANGE_64,
 601                        .mtime  = NO_CHANGE_64,
 602                        .device = device_number,
 603                };
 604                if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SET_UID) {
 605                        args.uid = current_fsuid();
 606                        args.gid = current_fsgid();
 607                } else {
 608                        args.uid = INVALID_UID; /* no change */
 609                        args.gid = INVALID_GID; /* no change */
 610                }
 611                rc = CIFSSMBUnixSetPathInfo(xid, pTcon, full_path, &args,
 612                                            cifs_sb->local_nls,
 613                                            cifs_sb->mnt_cifs_flags &
 614                                                CIFS_MOUNT_MAP_SPECIAL_CHR);
 615                if (rc)
 616                        goto mknod_out;
 617
 618                rc = cifs_get_inode_info_unix(&newinode, full_path,
 619                                                inode->i_sb, xid);
 620
 621                if (rc == 0)
 622                        d_instantiate(direntry, newinode);
 623                goto mknod_out;
 624        }
 625
 626        if (!(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL))
 627                goto mknod_out;
 628
 629
 630        cifs_dbg(FYI, "sfu compat create special file\n");
 631
 632        buf = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
 633        if (buf == NULL) {
 634                kfree(full_path);
 635                rc = -ENOMEM;
 636                free_xid(xid);
 637                return rc;
 638        }
 639
 640        if (backup_cred(cifs_sb))
 641                create_options |= CREATE_OPEN_BACKUP_INTENT;
 642
 643        rc = CIFSSMBOpen(xid, pTcon, full_path, FILE_CREATE,
 644                         GENERIC_WRITE, create_options,
 645                         &fileHandle, &oplock, buf, cifs_sb->local_nls,
 646                         cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR);
 647        if (rc)
 648                goto mknod_out;
 649
 650        /* BB Do not bother to decode buf since no local inode yet to put
 651         * timestamps in, but we can reuse it safely */
 652
 653        pdev = (struct win_dev *)buf;
 654        io_parms.netfid = fileHandle;
 655        io_parms.pid = current->tgid;
 656        io_parms.tcon = pTcon;
 657        io_parms.offset = 0;
 658        io_parms.length = sizeof(struct win_dev);
 659        if (S_ISCHR(mode)) {
 660                memcpy(pdev->type, "IntxCHR", 8);
 661                pdev->major =
 662                      cpu_to_le64(MAJOR(device_number));
 663                pdev->minor =
 664                      cpu_to_le64(MINOR(device_number));
 665                rc = CIFSSMBWrite(xid, &io_parms,
 666                        &bytes_written, (char *)pdev,
 667                        NULL, 0);
 668        } else if (S_ISBLK(mode)) {
 669                memcpy(pdev->type, "IntxBLK", 8);
 670                pdev->major =
 671                      cpu_to_le64(MAJOR(device_number));
 672                pdev->minor =
 673                      cpu_to_le64(MINOR(device_number));
 674                rc = CIFSSMBWrite(xid, &io_parms,
 675                        &bytes_written, (char *)pdev,
 676                        NULL, 0);
 677        } /* else if (S_ISFIFO) */
 678        CIFSSMBClose(xid, pTcon, fileHandle);
 679        d_drop(direntry);
 680
 681        /* FIXME: add code here to set EAs */
 682
 683mknod_out:
 684        kfree(full_path);
 685        kfree(buf);
 686        free_xid(xid);
 687        cifs_put_tlink(tlink);
 688        return rc;
 689}
 690
 691struct dentry *
 692cifs_lookup(struct inode *parent_dir_inode, struct dentry *direntry,
 693            unsigned int flags)
 694{
 695        unsigned int xid;
 696        int rc = 0; /* to get around spurious gcc warning, set to zero here */
 697        struct cifs_sb_info *cifs_sb;
 698        struct tcon_link *tlink;
 699        struct cifs_tcon *pTcon;
 700        struct inode *newInode = NULL;
 701        char *full_path = NULL;
 702
 703        xid = get_xid();
 704
 705        cifs_dbg(FYI, "parent inode = 0x%p name is: %s and dentry = 0x%p\n",
 706                 parent_dir_inode, direntry->d_name.name, direntry);
 707
 708        /* check whether path exists */
 709
 710        cifs_sb = CIFS_SB(parent_dir_inode->i_sb);
 711        tlink = cifs_sb_tlink(cifs_sb);
 712        if (IS_ERR(tlink)) {
 713                free_xid(xid);
 714                return (struct dentry *)tlink;
 715        }
 716        pTcon = tlink_tcon(tlink);
 717
 718        rc = check_name(direntry);
 719        if (rc)
 720                goto lookup_out;
 721
 722        /* can not grab the rename sem here since it would
 723        deadlock in the cases (beginning of sys_rename itself)
 724        in which we already have the sb rename sem */
 725        full_path = build_path_from_dentry(direntry);
 726        if (full_path == NULL) {
 727                rc = -ENOMEM;
 728                goto lookup_out;
 729        }
 730
 731        if (direntry->d_inode != NULL) {
 732                cifs_dbg(FYI, "non-NULL inode in lookup\n");
 733        } else {
 734                cifs_dbg(FYI, "NULL inode in lookup\n");
 735        }
 736        cifs_dbg(FYI, "Full path: %s inode = 0x%p\n",
 737                 full_path, direntry->d_inode);
 738
 739        if (pTcon->unix_ext) {
 740                rc = cifs_get_inode_info_unix(&newInode, full_path,
 741                                              parent_dir_inode->i_sb, xid);
 742        } else {
 743                rc = cifs_get_inode_info(&newInode, full_path, NULL,
 744                                parent_dir_inode->i_sb, xid, NULL);
 745        }
 746
 747        if ((rc == 0) && (newInode != NULL)) {
 748                d_add(direntry, newInode);
 749                /* since paths are not looked up by component - the parent
 750                   directories are presumed to be good here */
 751                renew_parental_timestamps(direntry);
 752
 753        } else if (rc == -ENOENT) {
 754                rc = 0;
 755                direntry->d_time = jiffies;
 756                d_add(direntry, NULL);
 757        /*      if it was once a directory (but how can we tell?) we could do
 758                shrink_dcache_parent(direntry); */
 759        } else if (rc != -EACCES) {
 760                cifs_dbg(FYI, "Unexpected lookup error %d\n", rc);
 761                /* We special case check for Access Denied - since that
 762                is a common return code */
 763        }
 764
 765lookup_out:
 766        kfree(full_path);
 767        cifs_put_tlink(tlink);
 768        free_xid(xid);
 769        return ERR_PTR(rc);
 770}
 771
 772static int
 773cifs_d_revalidate(struct dentry *direntry, unsigned int flags)
 774{
 775        if (flags & LOOKUP_RCU)
 776                return -ECHILD;
 777
 778        if (direntry->d_inode) {
 779                if (cifs_revalidate_dentry(direntry))
 780                        return 0;
 781                else {
 782                        /*
 783                         * If the inode wasn't known to be a dfs entry when
 784                         * the dentry was instantiated, such as when created
 785                         * via ->readdir(), it needs to be set now since the
 786                         * attributes will have been updated by
 787                         * cifs_revalidate_dentry().
 788                         */
 789                        if (IS_AUTOMOUNT(direntry->d_inode) &&
 790                           !(direntry->d_flags & DCACHE_NEED_AUTOMOUNT)) {
 791                                spin_lock(&direntry->d_lock);
 792                                direntry->d_flags |= DCACHE_NEED_AUTOMOUNT;
 793                                spin_unlock(&direntry->d_lock);
 794                        }
 795
 796                        return 1;
 797                }
 798        }
 799
 800        /*
 801         * This may be nfsd (or something), anyway, we can't see the
 802         * intent of this. So, since this can be for creation, drop it.
 803         */
 804        if (!flags)
 805                return 0;
 806
 807        /*
 808         * Drop the negative dentry, in order to make sure to use the
 809         * case sensitive name which is specified by user if this is
 810         * for creation.
 811         */
 812        if (flags & (LOOKUP_CREATE | LOOKUP_RENAME_TARGET))
 813                return 0;
 814
 815        if (time_after(jiffies, direntry->d_time + HZ) || !lookupCacheEnabled)
 816                return 0;
 817
 818        return 1;
 819}
 820
 821/* static int cifs_d_delete(struct dentry *direntry)
 822{
 823        int rc = 0;
 824
 825        cifs_dbg(FYI, "In cifs d_delete, name = %s\n", direntry->d_name.name);
 826
 827        return rc;
 828}     */
 829
 830const struct dentry_operations cifs_dentry_ops = {
 831        .d_revalidate = cifs_d_revalidate,
 832        .d_automount = cifs_dfs_d_automount,
 833/* d_delete:       cifs_d_delete,      */ /* not needed except for debugging */
 834};
 835
 836static int cifs_ci_hash(const struct dentry *dentry, struct qstr *q)
 837{
 838        struct nls_table *codepage = CIFS_SB(dentry->d_sb)->local_nls;
 839        unsigned long hash;
 840        wchar_t c;
 841        int i, charlen;
 842
 843        hash = init_name_hash();
 844        for (i = 0; i < q->len; i += charlen) {
 845                charlen = codepage->char2uni(&q->name[i], q->len - i, &c);
 846                /* error out if we can't convert the character */
 847                if (unlikely(charlen < 0))
 848                        return charlen;
 849                hash = partial_name_hash(cifs_toupper(c), hash);
 850        }
 851        q->hash = end_name_hash(hash);
 852
 853        return 0;
 854}
 855
 856static int cifs_ci_compare(const struct dentry *parent, const struct dentry *dentry,
 857                unsigned int len, const char *str, const struct qstr *name)
 858{
 859        struct nls_table *codepage = CIFS_SB(parent->d_sb)->local_nls;
 860        wchar_t c1, c2;
 861        int i, l1, l2;
 862
 863        /*
 864         * We make the assumption here that uppercase characters in the local
 865         * codepage are always the same length as their lowercase counterparts.
 866         *
 867         * If that's ever not the case, then this will fail to match it.
 868         */
 869        if (name->len != len)
 870                return 1;
 871
 872        for (i = 0; i < len; i += l1) {
 873                /* Convert characters in both strings to UTF-16. */
 874                l1 = codepage->char2uni(&str[i], len - i, &c1);
 875                l2 = codepage->char2uni(&name->name[i], name->len - i, &c2);
 876
 877                /*
 878                 * If we can't convert either character, just declare it to
 879                 * be 1 byte long and compare the original byte.
 880                 */
 881                if (unlikely(l1 < 0 && l2 < 0)) {
 882                        if (str[i] != name->name[i])
 883                                return 1;
 884                        l1 = 1;
 885                        continue;
 886                }
 887
 888                /*
 889                 * Here, we again ass|u|me that upper/lowercase versions of
 890                 * a character are the same length in the local NLS.
 891                 */
 892                if (l1 != l2)
 893                        return 1;
 894
 895                /* Now compare uppercase versions of these characters */
 896                if (cifs_toupper(c1) != cifs_toupper(c2))
 897                        return 1;
 898        }
 899
 900        return 0;
 901}
 902
 903const struct dentry_operations cifs_ci_dentry_ops = {
 904        .d_revalidate = cifs_d_revalidate,
 905        .d_hash = cifs_ci_hash,
 906        .d_compare = cifs_ci_compare,
 907        .d_automount = cifs_dfs_d_automount,
 908};
 909